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-rw-r--r--src/vppinfra/dlmalloc.c5098
1 files changed, 5098 insertions, 0 deletions
diff --git a/src/vppinfra/dlmalloc.c b/src/vppinfra/dlmalloc.c
new file mode 100644
index 00000000000..8acea8bc2bf
--- /dev/null
+++ b/src/vppinfra/dlmalloc.c
@@ -0,0 +1,5098 @@
+/*
+ This is a version (aka dlmalloc) of malloc/free/realloc written by
+ Doug Lea and released to the public domain, as explained at
+ http://creativecommons.org/publicdomain/zero/1.0/ Send questions,
+ comments, complaints, performance data, etc to dl@cs.oswego.edu
+*/
+
+#include <vppinfra/dlmalloc.h>
+
+/*------------------------------ internal #includes ---------------------- */
+
+#ifdef _MSC_VER
+#pragma warning( disable : 4146 ) /* no "unsigned" warnings */
+#endif /* _MSC_VER */
+#if !NO_MALLOC_STATS
+#include <stdio.h> /* for printing in malloc_stats */
+#endif /* NO_MALLOC_STATS */
+#ifndef LACKS_ERRNO_H
+#include <errno.h> /* for MALLOC_FAILURE_ACTION */
+#endif /* LACKS_ERRNO_H */
+#ifdef DEBUG
+#if DLM_ABORT_ON_ASSERT_FAILURE
+#undef assert
+#define assert(x) if(!(x)) DLM_ABORT
+#else /* DLM_ABORT_ON_ASSERT_FAILURE */
+#include <assert.h>
+#endif /* DLM_ABORT_ON_ASSERT_FAILURE */
+#else /* DEBUG */
+#ifndef assert
+#define assert(x)
+#endif
+#define DEBUG 0
+#endif /* DEBUG */
+#if !defined(WIN32) && !defined(LACKS_TIME_H)
+#include <time.h> /* for magic initialization */
+#endif /* WIN32 */
+#ifndef LACKS_STDLIB_H
+#include <stdlib.h> /* for abort() */
+#endif /* LACKS_STDLIB_H */
+#ifndef LACKS_STRING_H
+#include <string.h> /* for memset etc */
+#endif /* LACKS_STRING_H */
+#if USE_BUILTIN_FFS
+#ifndef LACKS_STRINGS_H
+#include <strings.h> /* for ffs */
+#endif /* LACKS_STRINGS_H */
+#endif /* USE_BUILTIN_FFS */
+#if HAVE_MMAP
+#ifndef LACKS_SYS_MMAN_H
+/* On some versions of linux, mremap decl in mman.h needs __USE_GNU set */
+#if (defined(linux) && !defined(__USE_GNU))
+#define __USE_GNU 1
+#include <sys/mman.h> /* for mmap */
+#undef __USE_GNU
+#else
+#include <sys/mman.h> /* for mmap */
+#endif /* linux */
+#endif /* LACKS_SYS_MMAN_H */
+#ifndef LACKS_FCNTL_H
+#include <fcntl.h>
+#endif /* LACKS_FCNTL_H */
+#endif /* HAVE_MMAP */
+#ifndef LACKS_UNISTD_H
+#include <unistd.h> /* for sbrk, sysconf */
+#else /* LACKS_UNISTD_H */
+#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__)
+extern void* sbrk(ptrdiff_t);
+#endif /* FreeBSD etc */
+#endif /* LACKS_UNISTD_H */
+
+/* Declarations for locking */
+#if USE_LOCKS
+#ifndef WIN32
+#if defined (__SVR4) && defined (__sun) /* solaris */
+#include <thread.h>
+#elif !defined(LACKS_SCHED_H)
+#include <sched.h>
+#endif /* solaris or LACKS_SCHED_H */
+#if (defined(USE_RECURSIVE_LOCKS) && USE_RECURSIVE_LOCKS != 0) || !USE_SPIN_LOCKS
+#include <pthread.h>
+#endif /* USE_RECURSIVE_LOCKS ... */
+#elif defined(_MSC_VER)
+#ifndef _M_AMD64
+/* These are already defined on AMD64 builds */
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+LONG __cdecl _InterlockedCompareExchange(LONG volatile *Dest, LONG Exchange, LONG Comp);
+LONG __cdecl _InterlockedExchange(LONG volatile *Target, LONG Value);
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+#endif /* _M_AMD64 */
+#pragma intrinsic (_InterlockedCompareExchange)
+#pragma intrinsic (_InterlockedExchange)
+#define interlockedcompareexchange _InterlockedCompareExchange
+#define interlockedexchange _InterlockedExchange
+#elif defined(WIN32) && defined(__GNUC__)
+#define interlockedcompareexchange(a, b, c) __sync_val_compare_and_swap(a, c, b)
+#define interlockedexchange __sync_lock_test_and_set
+#endif /* Win32 */
+#else /* USE_LOCKS */
+#endif /* USE_LOCKS */
+
+#ifndef LOCK_AT_FORK
+#define LOCK_AT_FORK 0
+#endif
+
+/* Declarations for bit scanning on win32 */
+#if defined(_MSC_VER) && _MSC_VER>=1300
+#ifndef BitScanForward /* Try to avoid pulling in WinNT.h */
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+unsigned char _BitScanForward(unsigned long *index, unsigned long mask);
+unsigned char _BitScanReverse(unsigned long *index, unsigned long mask);
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#define BitScanForward _BitScanForward
+#define BitScanReverse _BitScanReverse
+#pragma intrinsic(_BitScanForward)
+#pragma intrinsic(_BitScanReverse)
+#endif /* BitScanForward */
+#endif /* defined(_MSC_VER) && _MSC_VER>=1300 */
+
+#ifndef WIN32
+#ifndef malloc_getpagesize
+# ifdef _SC_PAGESIZE /* some SVR4 systems omit an underscore */
+# ifndef _SC_PAGE_SIZE
+# define _SC_PAGE_SIZE _SC_PAGESIZE
+# endif
+# endif
+# ifdef _SC_PAGE_SIZE
+# define malloc_getpagesize sysconf(_SC_PAGE_SIZE)
+# else
+# if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE)
+ extern size_t getpagesize();
+# define malloc_getpagesize getpagesize()
+# else
+# ifdef WIN32 /* use supplied emulation of getpagesize */
+# define malloc_getpagesize getpagesize()
+# else
+# ifndef LACKS_SYS_PARAM_H
+# include <sys/param.h>
+# endif
+# ifdef EXEC_PAGESIZE
+# define malloc_getpagesize EXEC_PAGESIZE
+# else
+# ifdef NBPG
+# ifndef CLSIZE
+# define malloc_getpagesize NBPG
+# else
+# define malloc_getpagesize (NBPG * CLSIZE)
+# endif
+# else
+# ifdef NBPC
+# define malloc_getpagesize NBPC
+# else
+# ifdef PAGESIZE
+# define malloc_getpagesize PAGESIZE
+# else /* just guess */
+# define malloc_getpagesize ((size_t)4096U)
+# endif
+# endif
+# endif
+# endif
+# endif
+# endif
+# endif
+#endif
+#endif
+
+/* ------------------- size_t and alignment properties -------------------- */
+
+/* The byte and bit size of a size_t */
+#define SIZE_T_SIZE (sizeof(size_t))
+#define SIZE_T_BITSIZE (sizeof(size_t) << 3)
+
+/* Some constants coerced to size_t */
+/* Annoying but necessary to avoid errors on some platforms */
+#define SIZE_T_ZERO ((size_t)0)
+#define SIZE_T_ONE ((size_t)1)
+#define SIZE_T_TWO ((size_t)2)
+#define SIZE_T_FOUR ((size_t)4)
+#define TWO_SIZE_T_SIZES (SIZE_T_SIZE<<1)
+#define FOUR_SIZE_T_SIZES (SIZE_T_SIZE<<2)
+#define SIX_SIZE_T_SIZES (FOUR_SIZE_T_SIZES+TWO_SIZE_T_SIZES)
+#define HALF_MAX_SIZE_T (MAX_SIZE_T / 2U)
+
+/* The bit mask value corresponding to MALLOC_ALIGNMENT */
+#define CHUNK_ALIGN_MASK (MALLOC_ALIGNMENT - SIZE_T_ONE)
+
+/* True if address a has acceptable alignment */
+#define is_aligned(A) (((size_t)((A)) & (CHUNK_ALIGN_MASK)) == 0)
+
+/* the number of bytes to offset an address to align it */
+#define align_offset(A)\
+ ((((size_t)(A) & CHUNK_ALIGN_MASK) == 0)? 0 :\
+ ((MALLOC_ALIGNMENT - ((size_t)(A) & CHUNK_ALIGN_MASK)) & CHUNK_ALIGN_MASK))
+
+/* -------------------------- MMAP preliminaries ------------------------- */
+
+/*
+ If HAVE_MORECORE or HAVE_MMAP are false, we just define calls and
+ checks to fail so compiler optimizer can delete code rather than
+ using so many "#if"s.
+*/
+
+
+/* MORECORE and MMAP must return MFAIL on failure */
+#define MFAIL ((void*)(MAX_SIZE_T))
+#define CMFAIL ((char*)(MFAIL)) /* defined for convenience */
+
+#if HAVE_MMAP
+
+#ifndef WIN32
+#define MUNMAP_DEFAULT(a, s) munmap((a), (s))
+#define MMAP_PROT (PROT_READ|PROT_WRITE)
+#if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
+#define MAP_ANONYMOUS MAP_ANON
+#endif /* MAP_ANON */
+#ifdef MAP_ANONYMOUS
+#define MMAP_FLAGS (MAP_PRIVATE|MAP_ANONYMOUS)
+#define MMAP_DEFAULT(s) mmap(0, (s), MMAP_PROT, MMAP_FLAGS, -1, 0)
+#else /* MAP_ANONYMOUS */
+/*
+ Nearly all versions of mmap support MAP_ANONYMOUS, so the following
+ is unlikely to be needed, but is supplied just in case.
+*/
+#define MMAP_FLAGS (MAP_PRIVATE)
+static int dev_zero_fd = -1; /* Cached file descriptor for /dev/zero. */
+#define MMAP_DEFAULT(s) ((dev_zero_fd < 0) ? \
+ (dev_zero_fd = open("/dev/zero", O_RDWR), \
+ mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0)) : \
+ mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0))
+#endif /* MAP_ANONYMOUS */
+
+#define DIRECT_MMAP_DEFAULT(s) MMAP_DEFAULT(s)
+
+#else /* WIN32 */
+
+/* Win32 MMAP via VirtualAlloc */
+static FORCEINLINE void* win32mmap(size_t size) {
+ void* ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE);
+ return (ptr != 0)? ptr: MFAIL;
+}
+
+/* For direct MMAP, use MEM_TOP_DOWN to minimize interference */
+static FORCEINLINE void* win32direct_mmap(size_t size) {
+ void* ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT|MEM_TOP_DOWN,
+ PAGE_READWRITE);
+ return (ptr != 0)? ptr: MFAIL;
+}
+
+/* This function supports releasing coalesed segments */
+static FORCEINLINE int win32munmap(void* ptr, size_t size) {
+ MEMORY_BASIC_INFORMATION minfo;
+ char* cptr = (char*)ptr;
+ while (size) {
+ if (VirtualQuery(cptr, &minfo, sizeof(minfo)) == 0)
+ return -1;
+ if (minfo.BaseAddress != cptr || minfo.AllocationBase != cptr ||
+ minfo.State != MEM_COMMIT || minfo.RegionSize > size)
+ return -1;
+ if (VirtualFree(cptr, 0, MEM_RELEASE) == 0)
+ return -1;
+ cptr += minfo.RegionSize;
+ size -= minfo.RegionSize;
+ }
+ return 0;
+}
+
+#define MMAP_DEFAULT(s) win32mmap(s)
+#define MUNMAP_DEFAULT(a, s) win32munmap((a), (s))
+#define DIRECT_MMAP_DEFAULT(s) win32direct_mmap(s)
+#endif /* WIN32 */
+#endif /* HAVE_MMAP */
+
+#if HAVE_MREMAP
+#ifndef WIN32
+#define MREMAP_DEFAULT(addr, osz, nsz, mv) mremap((addr), (osz), (nsz), (mv))
+#endif /* WIN32 */
+#endif /* HAVE_MREMAP */
+
+/**
+ * Define CALL_MORECORE
+ */
+#if HAVE_MORECORE
+ #ifdef MORECORE
+ #define CALL_MORECORE(S) MORECORE(S)
+ #else /* MORECORE */
+ #define CALL_MORECORE(S) MORECORE_DEFAULT(S)
+ #endif /* MORECORE */
+#else /* HAVE_MORECORE */
+ #define CALL_MORECORE(S) MFAIL
+#endif /* HAVE_MORECORE */
+
+/**
+ * Define CALL_MMAP/CALL_MUNMAP/CALL_DIRECT_MMAP
+ */
+#if HAVE_MMAP
+ #define USE_MMAP_BIT (SIZE_T_ONE)
+
+ #ifdef MMAP
+ #define CALL_MMAP(s) MMAP(s)
+ #else /* MMAP */
+ #define CALL_MMAP(s) MMAP_DEFAULT(s)
+ #endif /* MMAP */
+ #ifdef MUNMAP
+ #define CALL_MUNMAP(a, s) MUNMAP((a), (s))
+ #else /* MUNMAP */
+ #define CALL_MUNMAP(a, s) MUNMAP_DEFAULT((a), (s))
+ #endif /* MUNMAP */
+ #ifdef DIRECT_MMAP
+ #define CALL_DIRECT_MMAP(s) DIRECT_MMAP(s)
+ #else /* DIRECT_MMAP */
+ #define CALL_DIRECT_MMAP(s) DIRECT_MMAP_DEFAULT(s)
+ #endif /* DIRECT_MMAP */
+#else /* HAVE_MMAP */
+ #define USE_MMAP_BIT (SIZE_T_ZERO)
+
+ #define MMAP(s) MFAIL
+ #define MUNMAP(a, s) (-1)
+ #define DIRECT_MMAP(s) MFAIL
+ #define CALL_DIRECT_MMAP(s) DIRECT_MMAP(s)
+ #define CALL_MMAP(s) MMAP(s)
+ #define CALL_MUNMAP(a, s) MUNMAP((a), (s))
+#endif /* HAVE_MMAP */
+
+/**
+ * Define CALL_MREMAP
+ */
+#if HAVE_MMAP && HAVE_MREMAP
+ #ifdef MREMAP
+ #define CALL_MREMAP(addr, osz, nsz, mv) MREMAP((addr), (osz), (nsz), (mv))
+ #else /* MREMAP */
+ #define CALL_MREMAP(addr, osz, nsz, mv) MREMAP_DEFAULT((addr), (osz), (nsz), (mv))
+ #endif /* MREMAP */
+#else /* HAVE_MMAP && HAVE_MREMAP */
+ #define CALL_MREMAP(addr, osz, nsz, mv) MFAIL
+#endif /* HAVE_MMAP && HAVE_MREMAP */
+
+/* mstate bit set if continguous morecore disabled or failed */
+#define USE_NONCONTIGUOUS_BIT (4U)
+
+/* mstate bit set if no expansion allowed */
+#define USE_NOEXPAND_BIT (8U)
+
+/* trace allocations if set */
+#define USE_TRACE_BIT (16U)
+
+/* segment bit set in create_mspace_with_base */
+#define EXTERN_BIT (8U)
+
+
+/* --------------------------- Lock preliminaries ------------------------ */
+
+/*
+ When locks are defined, there is one global lock, plus
+ one per-mspace lock.
+
+ The global lock_ensures that mparams.magic and other unique
+ mparams values are initialized only once. It also protects
+ sequences of calls to MORECORE. In many cases sys_alloc requires
+ two calls, that should not be interleaved with calls by other
+ threads. This does not protect against direct calls to MORECORE
+ by other threads not using this lock, so there is still code to
+ cope the best we can on interference.
+
+ Per-mspace locks surround calls to malloc, free, etc.
+ By default, locks are simple non-reentrant mutexes.
+
+ Because lock-protected regions generally have bounded times, it is
+ OK to use the supplied simple spinlocks. Spinlocks are likely to
+ improve performance for lightly contended applications, but worsen
+ performance under heavy contention.
+
+ If USE_LOCKS is > 1, the definitions of lock routines here are
+ bypassed, in which case you will need to define the type MLOCK_T,
+ and at least INITIAL_LOCK, DESTROY_LOCK, ACQUIRE_LOCK, RELEASE_LOCK
+ and TRY_LOCK. You must also declare a
+ static MLOCK_T malloc_global_mutex = { initialization values };.
+
+*/
+
+#if !USE_LOCKS
+#define USE_LOCK_BIT (0U)
+#define INITIAL_LOCK(l) (0)
+#define DESTROY_LOCK(l) (0)
+#define ACQUIRE_MALLOC_GLOBAL_LOCK()
+#define RELEASE_MALLOC_GLOBAL_LOCK()
+
+#else
+#if USE_LOCKS > 1
+/* ----------------------- User-defined locks ------------------------ */
+/* Define your own lock implementation here */
+/* #define INITIAL_LOCK(lk) ... */
+/* #define DESTROY_LOCK(lk) ... */
+/* #define ACQUIRE_LOCK(lk) ... */
+/* #define RELEASE_LOCK(lk) ... */
+/* #define TRY_LOCK(lk) ... */
+/* static MLOCK_T malloc_global_mutex = ... */
+
+#elif USE_SPIN_LOCKS
+
+/* First, define CAS_LOCK and CLEAR_LOCK on ints */
+/* Note CAS_LOCK defined to return 0 on success */
+
+#if defined(__GNUC__)&& (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1))
+#define CAS_LOCK(sl) __sync_lock_test_and_set(sl, 1)
+#define CLEAR_LOCK(sl) __sync_lock_release(sl)
+
+#elif (defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)))
+/* Custom spin locks for older gcc on x86 */
+static FORCEINLINE int x86_cas_lock(int *sl) {
+ int ret;
+ int val = 1;
+ int cmp = 0;
+ __asm__ __volatile__ ("lock; cmpxchgl %1, %2"
+ : "=a" (ret)
+ : "r" (val), "m" (*(sl)), "0"(cmp)
+ : "memory", "cc");
+ return ret;
+}
+
+static FORCEINLINE void x86_clear_lock(int* sl) {
+ assert(*sl != 0);
+ int prev = 0;
+ int ret;
+ __asm__ __volatile__ ("lock; xchgl %0, %1"
+ : "=r" (ret)
+ : "m" (*(sl)), "0"(prev)
+ : "memory");
+}
+
+#define CAS_LOCK(sl) x86_cas_lock(sl)
+#define CLEAR_LOCK(sl) x86_clear_lock(sl)
+
+#else /* Win32 MSC */
+#define CAS_LOCK(sl) interlockedexchange(sl, (LONG)1)
+#define CLEAR_LOCK(sl) interlockedexchange (sl, (LONG)0)
+
+#endif /* ... gcc spins locks ... */
+
+/* How to yield for a spin lock */
+#define SPINS_PER_YIELD 63
+#if defined(_MSC_VER)
+#define SLEEP_EX_DURATION 50 /* delay for yield/sleep */
+#define SPIN_LOCK_YIELD SleepEx(SLEEP_EX_DURATION, FALSE)
+#elif defined (__SVR4) && defined (__sun) /* solaris */
+#define SPIN_LOCK_YIELD thr_yield();
+#elif !defined(LACKS_SCHED_H)
+#define SPIN_LOCK_YIELD sched_yield();
+#else
+#define SPIN_LOCK_YIELD
+#endif /* ... yield ... */
+
+#if !defined(USE_RECURSIVE_LOCKS) || USE_RECURSIVE_LOCKS == 0
+/* Plain spin locks use single word (embedded in malloc_states) */
+static int spin_acquire_lock(int *sl) {
+ int spins = 0;
+ while (*(volatile int *)sl != 0 || CAS_LOCK(sl)) {
+ if ((++spins & SPINS_PER_YIELD) == 0) {
+ SPIN_LOCK_YIELD;
+ }
+ }
+ return 0;
+}
+
+#define MLOCK_T int
+#define TRY_LOCK(sl) !CAS_LOCK(sl)
+#define RELEASE_LOCK(sl) CLEAR_LOCK(sl)
+#define ACQUIRE_LOCK(sl) (CAS_LOCK(sl)? spin_acquire_lock(sl) : 0)
+#define INITIAL_LOCK(sl) (*sl = 0)
+#define DESTROY_LOCK(sl) (0)
+static MLOCK_T malloc_global_mutex = 0;
+
+#else /* USE_RECURSIVE_LOCKS */
+/* types for lock owners */
+#ifdef WIN32
+#define THREAD_ID_T DWORD
+#define CURRENT_THREAD GetCurrentThreadId()
+#define EQ_OWNER(X,Y) ((X) == (Y))
+#else
+/*
+ Note: the following assume that pthread_t is a type that can be
+ initialized to (casted) zero. If this is not the case, you will need to
+ somehow redefine these or not use spin locks.
+*/
+#define THREAD_ID_T pthread_t
+#define CURRENT_THREAD pthread_self()
+#define EQ_OWNER(X,Y) pthread_equal(X, Y)
+#endif
+
+struct malloc_recursive_lock {
+ int sl;
+ unsigned int c;
+ THREAD_ID_T threadid;
+};
+
+#define MLOCK_T struct malloc_recursive_lock
+static MLOCK_T malloc_global_mutex = { 0, 0, (THREAD_ID_T)0};
+
+static FORCEINLINE void recursive_release_lock(MLOCK_T *lk) {
+ assert(lk->sl != 0);
+ if (--lk->c == 0) {
+ CLEAR_LOCK(&lk->sl);
+ }
+}
+
+static FORCEINLINE int recursive_acquire_lock(MLOCK_T *lk) {
+ THREAD_ID_T mythreadid = CURRENT_THREAD;
+ int spins = 0;
+ for (;;) {
+ if (*((volatile int *)(&lk->sl)) == 0) {
+ if (!CAS_LOCK(&lk->sl)) {
+ lk->threadid = mythreadid;
+ lk->c = 1;
+ return 0;
+ }
+ }
+ else if (EQ_OWNER(lk->threadid, mythreadid)) {
+ ++lk->c;
+ return 0;
+ }
+ if ((++spins & SPINS_PER_YIELD) == 0) {
+ SPIN_LOCK_YIELD;
+ }
+ }
+}
+
+static FORCEINLINE int recursive_try_lock(MLOCK_T *lk) {
+ THREAD_ID_T mythreadid = CURRENT_THREAD;
+ if (*((volatile int *)(&lk->sl)) == 0) {
+ if (!CAS_LOCK(&lk->sl)) {
+ lk->threadid = mythreadid;
+ lk->c = 1;
+ return 1;
+ }
+ }
+ else if (EQ_OWNER(lk->threadid, mythreadid)) {
+ ++lk->c;
+ return 1;
+ }
+ return 0;
+}
+
+#define RELEASE_LOCK(lk) recursive_release_lock(lk)
+#define TRY_LOCK(lk) recursive_try_lock(lk)
+#define ACQUIRE_LOCK(lk) recursive_acquire_lock(lk)
+#define INITIAL_LOCK(lk) ((lk)->threadid = (THREAD_ID_T)0, (lk)->sl = 0, (lk)->c = 0)
+#define DESTROY_LOCK(lk) (0)
+#endif /* USE_RECURSIVE_LOCKS */
+
+#elif defined(WIN32) /* Win32 critical sections */
+#define MLOCK_T CRITICAL_SECTION
+#define ACQUIRE_LOCK(lk) (EnterCriticalSection(lk), 0)
+#define RELEASE_LOCK(lk) LeaveCriticalSection(lk)
+#define TRY_LOCK(lk) TryEnterCriticalSection(lk)
+#define INITIAL_LOCK(lk) (!InitializeCriticalSectionAndSpinCount((lk), 0x80000000|4000))
+#define DESTROY_LOCK(lk) (DeleteCriticalSection(lk), 0)
+#define NEED_GLOBAL_LOCK_INIT
+
+static MLOCK_T malloc_global_mutex;
+static volatile LONG malloc_global_mutex_status;
+
+/* Use spin loop to initialize global lock */
+static void init_malloc_global_mutex() {
+ for (;;) {
+ long stat = malloc_global_mutex_status;
+ if (stat > 0)
+ return;
+ /* transition to < 0 while initializing, then to > 0) */
+ if (stat == 0 &&
+ interlockedcompareexchange(&malloc_global_mutex_status, (LONG)-1, (LONG)0) == 0) {
+ InitializeCriticalSection(&malloc_global_mutex);
+ interlockedexchange(&malloc_global_mutex_status, (LONG)1);
+ return;
+ }
+ SleepEx(0, FALSE);
+ }
+}
+
+#else /* pthreads-based locks */
+#define MLOCK_T pthread_mutex_t
+#define ACQUIRE_LOCK(lk) pthread_mutex_lock(lk)
+#define RELEASE_LOCK(lk) pthread_mutex_unlock(lk)
+#define TRY_LOCK(lk) (!pthread_mutex_trylock(lk))
+#define INITIAL_LOCK(lk) pthread_init_lock(lk)
+#define DESTROY_LOCK(lk) pthread_mutex_destroy(lk)
+
+#if defined(USE_RECURSIVE_LOCKS) && USE_RECURSIVE_LOCKS != 0 && defined(linux) && !defined(PTHREAD_MUTEX_RECURSIVE)
+/* Cope with old-style linux recursive lock initialization by adding */
+/* skipped internal declaration from pthread.h */
+extern int pthread_mutexattr_setkind_np __P ((pthread_mutexattr_t *__attr,
+ int __kind));
+#define PTHREAD_MUTEX_RECURSIVE PTHREAD_MUTEX_RECURSIVE_NP
+#define pthread_mutexattr_settype(x,y) pthread_mutexattr_setkind_np(x,y)
+#endif /* USE_RECURSIVE_LOCKS ... */
+
+static MLOCK_T malloc_global_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+static int pthread_init_lock (MLOCK_T *lk) {
+ pthread_mutexattr_t attr;
+ if (pthread_mutexattr_init(&attr)) return 1;
+#if defined(USE_RECURSIVE_LOCKS) && USE_RECURSIVE_LOCKS != 0
+ if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) return 1;
+#endif
+ if (pthread_mutex_init(lk, &attr)) return 1;
+ if (pthread_mutexattr_destroy(&attr)) return 1;
+ return 0;
+}
+
+#endif /* ... lock types ... */
+
+/* Common code for all lock types */
+#define USE_LOCK_BIT (2U)
+
+#ifndef ACQUIRE_MALLOC_GLOBAL_LOCK
+#define ACQUIRE_MALLOC_GLOBAL_LOCK() ACQUIRE_LOCK(&malloc_global_mutex);
+#endif
+
+#ifndef RELEASE_MALLOC_GLOBAL_LOCK
+#define RELEASE_MALLOC_GLOBAL_LOCK() RELEASE_LOCK(&malloc_global_mutex);
+#endif
+
+#endif /* USE_LOCKS */
+
+/* ----------------------- Chunk representations ------------------------ */
+
+/*
+ (The following includes lightly edited explanations by Colin Plumb.)
+
+ The malloc_chunk declaration below is misleading (but accurate and
+ necessary). It declares a "view" into memory allowing access to
+ necessary fields at known offsets from a given base.
+
+ Chunks of memory are maintained using a `boundary tag' method as
+ originally described by Knuth. (See the paper by Paul Wilson
+ ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a survey of such
+ techniques.) Sizes of free chunks are stored both in the front of
+ each chunk and at the end. This makes consolidating fragmented
+ chunks into bigger chunks fast. The head fields also hold bits
+ representing whether chunks are free or in use.
+
+ Here are some pictures to make it clearer. They are "exploded" to
+ show that the state of a chunk can be thought of as extending from
+ the high 31 bits of the head field of its header through the
+ prev_foot and PINUSE_BIT bit of the following chunk header.
+
+ A chunk that's in use looks like:
+
+ chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Size of previous chunk (if P = 0) |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |P|
+ | Size of this chunk 1| +-+
+ mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | |
+ +- -+
+ | |
+ +- -+
+ | :
+ +- size - sizeof(size_t) available payload bytes -+
+ : |
+ chunk-> +- -+
+ | |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |1|
+ | Size of next chunk (may or may not be in use) | +-+
+ mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+ And if it's free, it looks like this:
+
+ chunk-> +- -+
+ | User payload (must be in use, or we would have merged!) |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |P|
+ | Size of this chunk 0| +-+
+ mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Next pointer |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Prev pointer |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | :
+ +- size - sizeof(struct chunk) unused bytes -+
+ : |
+ chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Size of this chunk |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0|
+ | Size of next chunk (must be in use, or we would have merged)| +-+
+ mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | :
+ +- User payload -+
+ : |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ |0|
+ +-+
+ Note that since we always merge adjacent free chunks, the chunks
+ adjacent to a free chunk must be in use.
+
+ Given a pointer to a chunk (which can be derived trivially from the
+ payload pointer) we can, in O(1) time, find out whether the adjacent
+ chunks are free, and if so, unlink them from the lists that they
+ are on and merge them with the current chunk.
+
+ Chunks always begin on even word boundaries, so the mem portion
+ (which is returned to the user) is also on an even word boundary, and
+ thus at least double-word aligned.
+
+ The P (PINUSE_BIT) bit, stored in the unused low-order bit of the
+ chunk size (which is always a multiple of two words), is an in-use
+ bit for the *previous* chunk. If that bit is *clear*, then the
+ word before the current chunk size contains the previous chunk
+ size, and can be used to find the front of the previous chunk.
+ The very first chunk allocated always has this bit set, preventing
+ access to non-existent (or non-owned) memory. If pinuse is set for
+ any given chunk, then you CANNOT determine the size of the
+ previous chunk, and might even get a memory addressing fault when
+ trying to do so.
+
+ The C (CINUSE_BIT) bit, stored in the unused second-lowest bit of
+ the chunk size redundantly records whether the current chunk is
+ inuse (unless the chunk is mmapped). This redundancy enables usage
+ checks within free and realloc, and reduces indirection when freeing
+ and consolidating chunks.
+
+ Each freshly allocated chunk must have both cinuse and pinuse set.
+ That is, each allocated chunk borders either a previously allocated
+ and still in-use chunk, or the base of its memory arena. This is
+ ensured by making all allocations from the `lowest' part of any
+ found chunk. Further, no free chunk physically borders another one,
+ so each free chunk is known to be preceded and followed by either
+ inuse chunks or the ends of memory.
+
+ Note that the `foot' of the current chunk is actually represented
+ as the prev_foot of the NEXT chunk. This makes it easier to
+ deal with alignments etc but can be very confusing when trying
+ to extend or adapt this code.
+
+ The exceptions to all this are
+
+ 1. The special chunk `top' is the top-most available chunk (i.e.,
+ the one bordering the end of available memory). It is treated
+ specially. Top is never included in any bin, is used only if
+ no other chunk is available, and is released back to the
+ system if it is very large (see M_TRIM_THRESHOLD). In effect,
+ the top chunk is treated as larger (and thus less well
+ fitting) than any other available chunk. The top chunk
+ doesn't update its trailing size field since there is no next
+ contiguous chunk that would have to index off it. However,
+ space is still allocated for it (TOP_FOOT_SIZE) to enable
+ separation or merging when space is extended.
+
+ 3. Chunks allocated via mmap, have both cinuse and pinuse bits
+ cleared in their head fields. Because they are allocated
+ one-by-one, each must carry its own prev_foot field, which is
+ also used to hold the offset this chunk has within its mmapped
+ region, which is needed to preserve alignment. Each mmapped
+ chunk is trailed by the first two fields of a fake next-chunk
+ for sake of usage checks.
+
+*/
+
+struct malloc_chunk {
+ size_t prev_foot; /* Size of previous chunk (if free). */
+ size_t head; /* Size and inuse bits. */
+ struct malloc_chunk* fd; /* double links -- used only if free. */
+ struct malloc_chunk* bk;
+};
+
+typedef struct malloc_chunk mchunk;
+typedef struct malloc_chunk* mchunkptr;
+typedef struct malloc_chunk* sbinptr; /* The type of bins of chunks */
+typedef unsigned int bindex_t; /* Described below */
+typedef unsigned int binmap_t; /* Described below */
+typedef unsigned int flag_t; /* The type of various bit flag sets */
+
+/* ------------------- Chunks sizes and alignments ----------------------- */
+
+#define MCHUNK_SIZE (sizeof(mchunk))
+
+#if FOOTERS
+#define CHUNK_OVERHEAD (TWO_SIZE_T_SIZES)
+#else /* FOOTERS */
+#define CHUNK_OVERHEAD (SIZE_T_SIZE)
+#endif /* FOOTERS */
+
+/* MMapped chunks need a second word of overhead ... */
+#define MMAP_CHUNK_OVERHEAD (TWO_SIZE_T_SIZES)
+/* ... and additional padding for fake next-chunk at foot */
+#define MMAP_FOOT_PAD (FOUR_SIZE_T_SIZES)
+
+/* The smallest size we can malloc is an aligned minimal chunk */
+#define MIN_CHUNK_SIZE\
+ ((MCHUNK_SIZE + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK)
+
+/* conversion from malloc headers to user pointers, and back */
+#define chunk2mem(p) ((void*)((char*)(p) + TWO_SIZE_T_SIZES))
+#define mem2chunk(mem) ((mchunkptr)((char*)(mem) - TWO_SIZE_T_SIZES))
+/* chunk associated with aligned address A */
+#define align_as_chunk(A) (mchunkptr)((A) + align_offset(chunk2mem(A)))
+
+/* Bounds on request (not chunk) sizes. */
+#define MAX_REQUEST ((-MIN_CHUNK_SIZE) << 2)
+#define MIN_REQUEST (MIN_CHUNK_SIZE - CHUNK_OVERHEAD - SIZE_T_ONE)
+
+/* pad request bytes into a usable size */
+#define pad_request(req) \
+ (((req) + CHUNK_OVERHEAD + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK)
+
+/* pad request, checking for minimum (but not maximum) */
+#define request2size(req) \
+ (((req) < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(req))
+
+
+/* ------------------ Operations on head and foot fields ----------------- */
+
+/*
+ The head field of a chunk is or'ed with PINUSE_BIT when previous
+ adjacent chunk in use, and or'ed with CINUSE_BIT if this chunk is in
+ use, unless mmapped, in which case both bits are cleared.
+
+ FLAG4_BIT is not used by this malloc, but might be useful in extensions.
+*/
+
+#define PINUSE_BIT (SIZE_T_ONE)
+#define CINUSE_BIT (SIZE_T_TWO)
+#define FLAG4_BIT (SIZE_T_FOUR)
+#define INUSE_BITS (PINUSE_BIT|CINUSE_BIT)
+#define FLAG_BITS (PINUSE_BIT|CINUSE_BIT|FLAG4_BIT)
+
+/* Head value for fenceposts */
+#define FENCEPOST_HEAD (INUSE_BITS|SIZE_T_SIZE)
+
+/* extraction of fields from head words */
+#define cinuse(p) ((p)->head & CINUSE_BIT)
+#define pinuse(p) ((p)->head & PINUSE_BIT)
+#define flag4inuse(p) ((p)->head & FLAG4_BIT)
+#define is_inuse(p) (((p)->head & INUSE_BITS) != PINUSE_BIT)
+#define is_mmapped(p) (((p)->head & INUSE_BITS) == 0)
+
+#define chunksize(p) ((p)->head & ~(FLAG_BITS))
+
+#define clear_pinuse(p) ((p)->head &= ~PINUSE_BIT)
+#define set_flag4(p) ((p)->head |= FLAG4_BIT)
+#define clear_flag4(p) ((p)->head &= ~FLAG4_BIT)
+
+/* Treat space at ptr +/- offset as a chunk */
+#define chunk_plus_offset(p, s) ((mchunkptr)(((char*)(p)) + (s)))
+#define chunk_minus_offset(p, s) ((mchunkptr)(((char*)(p)) - (s)))
+
+/* Ptr to next or previous physical malloc_chunk. */
+#define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->head & ~FLAG_BITS)))
+#define prev_chunk(p) ((mchunkptr)( ((char*)(p)) - ((p)->prev_foot) ))
+
+/* extract next chunk's pinuse bit */
+#define next_pinuse(p) ((next_chunk(p)->head) & PINUSE_BIT)
+
+/* Get/set size at footer */
+#define get_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_foot)
+#define set_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_foot = (s))
+
+/* Set size, pinuse bit, and foot */
+#define set_size_and_pinuse_of_free_chunk(p, s)\
+ ((p)->head = (s|PINUSE_BIT), set_foot(p, s))
+
+/* Set size, pinuse bit, foot, and clear next pinuse */
+#define set_free_with_pinuse(p, s, n)\
+ (clear_pinuse(n), set_size_and_pinuse_of_free_chunk(p, s))
+
+/* Get the internal overhead associated with chunk p */
+#define overhead_for(p)\
+ (is_mmapped(p)? MMAP_CHUNK_OVERHEAD : CHUNK_OVERHEAD)
+
+/* Return true if malloced space is not necessarily cleared */
+#if MMAP_CLEARS
+#define calloc_must_clear(p) (!is_mmapped(p))
+#else /* MMAP_CLEARS */
+#define calloc_must_clear(p) (1)
+#endif /* MMAP_CLEARS */
+
+/* ---------------------- Overlaid data structures ----------------------- */
+
+/*
+ When chunks are not in use, they are treated as nodes of either
+ lists or trees.
+
+ "Small" chunks are stored in circular doubly-linked lists, and look
+ like this:
+
+ chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Size of previous chunk |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ `head:' | Size of chunk, in bytes |P|
+ mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Forward pointer to next chunk in list |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Back pointer to previous chunk in list |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Unused space (may be 0 bytes long) .
+ . .
+ . |
+nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ `foot:' | Size of chunk, in bytes |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+ Larger chunks are kept in a form of bitwise digital trees (aka
+ tries) keyed on chunksizes. Because malloc_tree_chunks are only for
+ free chunks greater than 256 bytes, their size doesn't impose any
+ constraints on user chunk sizes. Each node looks like:
+
+ chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Size of previous chunk |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ `head:' | Size of chunk, in bytes |P|
+ mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Forward pointer to next chunk of same size |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Back pointer to previous chunk of same size |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Pointer to left child (child[0]) |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Pointer to right child (child[1]) |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Pointer to parent |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | bin index of this chunk |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Unused space .
+ . |
+nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ `foot:' | Size of chunk, in bytes |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+ Each tree holding treenodes is a tree of unique chunk sizes. Chunks
+ of the same size are arranged in a circularly-linked list, with only
+ the oldest chunk (the next to be used, in our FIFO ordering)
+ actually in the tree. (Tree members are distinguished by a non-null
+ parent pointer.) If a chunk with the same size an an existing node
+ is inserted, it is linked off the existing node using pointers that
+ work in the same way as fd/bk pointers of small chunks.
+
+ Each tree contains a power of 2 sized range of chunk sizes (the
+ smallest is 0x100 <= x < 0x180), which is is divided in half at each
+ tree level, with the chunks in the smaller half of the range (0x100
+ <= x < 0x140 for the top nose) in the left subtree and the larger
+ half (0x140 <= x < 0x180) in the right subtree. This is, of course,
+ done by inspecting individual bits.
+
+ Using these rules, each node's left subtree contains all smaller
+ sizes than its right subtree. However, the node at the root of each
+ subtree has no particular ordering relationship to either. (The
+ dividing line between the subtree sizes is based on trie relation.)
+ If we remove the last chunk of a given size from the interior of the
+ tree, we need to replace it with a leaf node. The tree ordering
+ rules permit a node to be replaced by any leaf below it.
+
+ The smallest chunk in a tree (a common operation in a best-fit
+ allocator) can be found by walking a path to the leftmost leaf in
+ the tree. Unlike a usual binary tree, where we follow left child
+ pointers until we reach a null, here we follow the right child
+ pointer any time the left one is null, until we reach a leaf with
+ both child pointers null. The smallest chunk in the tree will be
+ somewhere along that path.
+
+ The worst case number of steps to add, find, or remove a node is
+ bounded by the number of bits differentiating chunks within
+ bins. Under current bin calculations, this ranges from 6 up to 21
+ (for 32 bit sizes) or up to 53 (for 64 bit sizes). The typical case
+ is of course much better.
+*/
+
+struct malloc_tree_chunk {
+ /* The first four fields must be compatible with malloc_chunk */
+ size_t prev_foot;
+ size_t head;
+ struct malloc_tree_chunk* fd;
+ struct malloc_tree_chunk* bk;
+
+ struct malloc_tree_chunk* child[2];
+ struct malloc_tree_chunk* parent;
+ bindex_t index;
+};
+
+typedef struct malloc_tree_chunk tchunk;
+typedef struct malloc_tree_chunk* tchunkptr;
+typedef struct malloc_tree_chunk* tbinptr; /* The type of bins of trees */
+
+/* A little helper macro for trees */
+#define leftmost_child(t) ((t)->child[0] != 0? (t)->child[0] : (t)->child[1])
+
+/* ----------------------------- Segments -------------------------------- */
+
+/*
+ Each malloc space may include non-contiguous segments, held in a
+ list headed by an embedded malloc_segment record representing the
+ top-most space. Segments also include flags holding properties of
+ the space. Large chunks that are directly allocated by mmap are not
+ included in this list. They are instead independently created and
+ destroyed without otherwise keeping track of them.
+
+ Segment management mainly comes into play for spaces allocated by
+ MMAP. Any call to MMAP might or might not return memory that is
+ adjacent to an existing segment. MORECORE normally contiguously
+ extends the current space, so this space is almost always adjacent,
+ which is simpler and faster to deal with. (This is why MORECORE is
+ used preferentially to MMAP when both are available -- see
+ sys_alloc.) When allocating using MMAP, we don't use any of the
+ hinting mechanisms (inconsistently) supported in various
+ implementations of unix mmap, or distinguish reserving from
+ committing memory. Instead, we just ask for space, and exploit
+ contiguity when we get it. It is probably possible to do
+ better than this on some systems, but no general scheme seems
+ to be significantly better.
+
+ Management entails a simpler variant of the consolidation scheme
+ used for chunks to reduce fragmentation -- new adjacent memory is
+ normally prepended or appended to an existing segment. However,
+ there are limitations compared to chunk consolidation that mostly
+ reflect the fact that segment processing is relatively infrequent
+ (occurring only when getting memory from system) and that we
+ don't expect to have huge numbers of segments:
+
+ * Segments are not indexed, so traversal requires linear scans. (It
+ would be possible to index these, but is not worth the extra
+ overhead and complexity for most programs on most platforms.)
+ * New segments are only appended to old ones when holding top-most
+ memory; if they cannot be prepended to others, they are held in
+ different segments.
+
+ Except for the top-most segment of an mstate, each segment record
+ is kept at the tail of its segment. Segments are added by pushing
+ segment records onto the list headed by &mstate.seg for the
+ containing mstate.
+
+ Segment flags control allocation/merge/deallocation policies:
+ * If EXTERN_BIT set, then we did not allocate this segment,
+ and so should not try to deallocate or merge with others.
+ (This currently holds only for the initial segment passed
+ into create_mspace_with_base.)
+ * If USE_MMAP_BIT set, the segment may be merged with
+ other surrounding mmapped segments and trimmed/de-allocated
+ using munmap.
+ * If neither bit is set, then the segment was obtained using
+ MORECORE so can be merged with surrounding MORECORE'd segments
+ and deallocated/trimmed using MORECORE with negative arguments.
+*/
+
+struct malloc_segment {
+ char* base; /* base address */
+ size_t size; /* allocated size */
+ struct malloc_segment* next; /* ptr to next segment */
+ flag_t sflags; /* mmap and extern flag */
+};
+
+#define is_mmapped_segment(S) ((S)->sflags & USE_MMAP_BIT)
+#define is_extern_segment(S) ((S)->sflags & EXTERN_BIT)
+
+typedef struct malloc_segment msegment;
+typedef struct malloc_segment* msegmentptr;
+
+/* ---------------------------- malloc_state ----------------------------- */
+
+/*
+ A malloc_state holds all of the bookkeeping for a space.
+ The main fields are:
+
+ Top
+ The topmost chunk of the currently active segment. Its size is
+ cached in topsize. The actual size of topmost space is
+ topsize+TOP_FOOT_SIZE, which includes space reserved for adding
+ fenceposts and segment records if necessary when getting more
+ space from the system. The size at which to autotrim top is
+ cached from mparams in trim_check, except that it is disabled if
+ an autotrim fails.
+
+ Designated victim (dv)
+ This is the preferred chunk for servicing small requests that
+ don't have exact fits. It is normally the chunk split off most
+ recently to service another small request. Its size is cached in
+ dvsize. The link fields of this chunk are not maintained since it
+ is not kept in a bin.
+
+ SmallBins
+ An array of bin headers for free chunks. These bins hold chunks
+ with sizes less than MIN_LARGE_SIZE bytes. Each bin contains
+ chunks of all the same size, spaced 8 bytes apart. To simplify
+ use in double-linked lists, each bin header acts as a malloc_chunk
+ pointing to the real first node, if it exists (else pointing to
+ itself). This avoids special-casing for headers. But to avoid
+ waste, we allocate only the fd/bk pointers of bins, and then use
+ repositioning tricks to treat these as the fields of a chunk.
+
+ TreeBins
+ Treebins are pointers to the roots of trees holding a range of
+ sizes. There are 2 equally spaced treebins for each power of two
+ from TREE_SHIFT to TREE_SHIFT+16. The last bin holds anything
+ larger.
+
+ Bin maps
+ There is one bit map for small bins ("smallmap") and one for
+ treebins ("treemap). Each bin sets its bit when non-empty, and
+ clears the bit when empty. Bit operations are then used to avoid
+ bin-by-bin searching -- nearly all "search" is done without ever
+ looking at bins that won't be selected. The bit maps
+ conservatively use 32 bits per map word, even if on 64bit system.
+ For a good description of some of the bit-based techniques used
+ here, see Henry S. Warren Jr's book "Hacker's Delight" (and
+ supplement at http://hackersdelight.org/). Many of these are
+ intended to reduce the branchiness of paths through malloc etc, as
+ well as to reduce the number of memory locations read or written.
+
+ Segments
+ A list of segments headed by an embedded malloc_segment record
+ representing the initial space.
+
+ Address check support
+ The least_addr field is the least address ever obtained from
+ MORECORE or MMAP. Attempted frees and reallocs of any address less
+ than this are trapped (unless INSECURE is defined).
+
+ Magic tag
+ A cross-check field that should always hold same value as mparams.magic.
+
+ Max allowed footprint
+ The maximum allowed bytes to allocate from system (zero means no limit)
+
+ Flags
+ Bits recording whether to use MMAP, locks, or contiguous MORECORE
+
+ Statistics
+ Each space keeps track of current and maximum system memory
+ obtained via MORECORE or MMAP.
+
+ Trim support
+ Fields holding the amount of unused topmost memory that should trigger
+ trimming, and a counter to force periodic scanning to release unused
+ non-topmost segments.
+
+ Locking
+ If USE_LOCKS is defined, the "mutex" lock is acquired and released
+ around every public call using this mspace.
+
+ Extension support
+ A void* pointer and a size_t field that can be used to help implement
+ extensions to this malloc.
+*/
+
+/* Bin types, widths and sizes */
+#define NSMALLBINS (32U)
+#define NTREEBINS (32U)
+#define SMALLBIN_SHIFT (3U)
+#define SMALLBIN_WIDTH (SIZE_T_ONE << SMALLBIN_SHIFT)
+#define TREEBIN_SHIFT (8U)
+#define MIN_LARGE_SIZE (SIZE_T_ONE << TREEBIN_SHIFT)
+#define MAX_SMALL_SIZE (MIN_LARGE_SIZE - SIZE_T_ONE)
+#define MAX_SMALL_REQUEST (MAX_SMALL_SIZE - CHUNK_ALIGN_MASK - CHUNK_OVERHEAD)
+
+struct malloc_state {
+ binmap_t smallmap;
+ binmap_t treemap;
+ size_t dvsize;
+ size_t topsize;
+ char* least_addr;
+ mchunkptr dv;
+ mchunkptr top;
+ size_t trim_check;
+ size_t release_checks;
+ size_t magic;
+ mchunkptr smallbins[(NSMALLBINS+1)*2];
+ tbinptr treebins[NTREEBINS];
+ size_t footprint;
+ size_t max_footprint;
+ size_t footprint_limit; /* zero means no limit */
+ flag_t mflags;
+#if USE_LOCKS
+ MLOCK_T mutex; /* locate lock among fields that rarely change */
+#endif /* USE_LOCKS */
+ msegment seg;
+ void* extp; /* Unused but available for extensions */
+ size_t exts;
+};
+
+typedef struct malloc_state* mstate;
+
+/* ------------- Global malloc_state and malloc_params ------------------- */
+
+/*
+ malloc_params holds global properties, including those that can be
+ dynamically set using mallopt. There is a single instance, mparams,
+ initialized in init_mparams. Note that the non-zeroness of "magic"
+ also serves as an initialization flag.
+*/
+
+struct malloc_params {
+ size_t magic;
+ size_t page_size;
+ size_t granularity;
+ size_t mmap_threshold;
+ size_t trim_threshold;
+ flag_t default_mflags;
+};
+
+static struct malloc_params mparams;
+
+/* Ensure mparams initialized */
+#define ensure_initialization() (void)(mparams.magic != 0 || init_mparams())
+
+#if !ONLY_MSPACES
+
+/* The global malloc_state used for all non-"mspace" calls */
+static struct malloc_state _gm_;
+#define gm (&_gm_)
+#define is_global(M) ((M) == &_gm_)
+
+#endif /* !ONLY_MSPACES */
+
+#define is_initialized(M) ((M)->top != 0)
+
+/* -------------------------- system alloc setup ------------------------- */
+
+/* Operations on mflags */
+
+#define use_lock(M) ((M)->mflags & USE_LOCK_BIT)
+#define enable_lock(M) ((M)->mflags |= USE_LOCK_BIT)
+#if USE_LOCKS
+#define disable_lock(M) ((M)->mflags &= ~USE_LOCK_BIT)
+#else
+#define disable_lock(M)
+#endif
+
+#define use_mmap(M) ((M)->mflags & USE_MMAP_BIT)
+#define enable_mmap(M) ((M)->mflags |= USE_MMAP_BIT)
+#if HAVE_MMAP
+#define disable_mmap(M) ((M)->mflags &= ~USE_MMAP_BIT)
+#else
+#define disable_mmap(M)
+#endif
+
+#define use_noncontiguous(M) ((M)->mflags & USE_NONCONTIGUOUS_BIT)
+#define disable_contiguous(M) ((M)->mflags |= USE_NONCONTIGUOUS_BIT)
+#define use_noexpand(M) ((M)->mflags & USE_NOEXPAND_BIT)
+#define disable_expand(M) ((M)->mflags |= USE_NOEXPAND_BIT)
+#define use_trace(M) ((M)->mflags & USE_TRACE_BIT)
+#define enable_trace(M) ((M)->mflags |= USE_TRACE_BIT)
+#define disable_trace(M) ((M)->mflags |= USE_TRACE_BIT)
+
+#define set_lock(M,L)\
+ ((M)->mflags = (L)?\
+ ((M)->mflags | USE_LOCK_BIT) :\
+ ((M)->mflags & ~USE_LOCK_BIT))
+
+/* page-align a size */
+#define page_align(S)\
+ (((S) + (mparams.page_size - SIZE_T_ONE)) & ~(mparams.page_size - SIZE_T_ONE))
+
+/* granularity-align a size */
+#define granularity_align(S)\
+ (((S) + (mparams.granularity - SIZE_T_ONE))\
+ & ~(mparams.granularity - SIZE_T_ONE))
+
+
+/* For mmap, use granularity alignment on windows, else page-align */
+#ifdef WIN32
+#define mmap_align(S) granularity_align(S)
+#else
+#define mmap_align(S) page_align(S)
+#endif
+
+/* For sys_alloc, enough padding to ensure can malloc request on success */
+#define SYS_ALLOC_PADDING (TOP_FOOT_SIZE + MALLOC_ALIGNMENT)
+
+#define is_page_aligned(S)\
+ (((size_t)(S) & (mparams.page_size - SIZE_T_ONE)) == 0)
+#define is_granularity_aligned(S)\
+ (((size_t)(S) & (mparams.granularity - SIZE_T_ONE)) == 0)
+
+/* True if segment S holds address A */
+#define segment_holds(S, A)\
+ ((char*)(A) >= S->base && (char*)(A) < S->base + S->size)
+
+/* Return segment holding given address */
+static msegmentptr segment_holding(mstate m, char* addr) {
+ msegmentptr sp = &m->seg;
+ for (;;) {
+ if (addr >= sp->base && addr < sp->base + sp->size)
+ return sp;
+ if ((sp = sp->next) == 0)
+ return 0;
+ }
+}
+
+/* Return true if segment contains a segment link */
+static int has_segment_link(mstate m, msegmentptr ss) {
+ msegmentptr sp = &m->seg;
+ for (;;) {
+ if ((char*)sp >= ss->base && (char*)sp < ss->base + ss->size)
+ return 1;
+ if ((sp = sp->next) == 0)
+ return 0;
+ }
+}
+
+#ifndef MORECORE_CANNOT_TRIM
+#define should_trim(M,s) ((s) > (M)->trim_check)
+#else /* MORECORE_CANNOT_TRIM */
+#define should_trim(M,s) (0)
+#endif /* MORECORE_CANNOT_TRIM */
+
+/*
+ TOP_FOOT_SIZE is padding at the end of a segment, including space
+ that may be needed to place segment records and fenceposts when new
+ noncontiguous segments are added.
+*/
+#define TOP_FOOT_SIZE\
+ (align_offset(chunk2mem(0))+pad_request(sizeof(struct malloc_segment))+MIN_CHUNK_SIZE)
+
+
+/* ------------------------------- Hooks -------------------------------- */
+
+/*
+ PREACTION should be defined to return 0 on success, and nonzero on
+ failure. If you are not using locking, you can redefine these to do
+ anything you like.
+*/
+
+#if USE_LOCKS
+#define PREACTION(M) ((use_lock(M))? ACQUIRE_LOCK(&(M)->mutex) : 0)
+#define POSTACTION(M) { if (use_lock(M)) RELEASE_LOCK(&(M)->mutex); }
+#else /* USE_LOCKS */
+
+#ifndef PREACTION
+#define PREACTION(M) (0)
+#endif /* PREACTION */
+
+#ifndef POSTACTION
+#define POSTACTION(M)
+#endif /* POSTACTION */
+
+#endif /* USE_LOCKS */
+
+/*
+ CORRUPTION_ERROR_ACTION is triggered upon detected bad addresses.
+ USAGE_ERROR_ACTION is triggered on detected bad frees and
+ reallocs. The argument p is an address that might have triggered the
+ fault. It is ignored by the two predefined actions, but might be
+ useful in custom actions that try to help diagnose errors.
+*/
+
+#if PROCEED_ON_ERROR
+
+/* A count of the number of corruption errors causing resets */
+int malloc_corruption_error_count;
+
+/* default corruption action */
+static void reset_on_error(mstate m);
+
+#define CORRUPTION_ERROR_ACTION(m) reset_on_error(m)
+#define USAGE_ERROR_ACTION(m, p)
+
+#else /* PROCEED_ON_ERROR */
+
+#ifndef CORRUPTION_ERROR_ACTION
+#define CORRUPTION_ERROR_ACTION(m) DLM_ABORT
+#endif /* CORRUPTION_ERROR_ACTION */
+
+#ifndef USAGE_ERROR_ACTION
+#define USAGE_ERROR_ACTION(m,p) DLM_ABORT
+#endif /* USAGE_ERROR_ACTION */
+
+#endif /* PROCEED_ON_ERROR */
+
+
+/* -------------------------- Debugging setup ---------------------------- */
+
+#if ! DEBUG
+
+#define check_free_chunk(M,P)
+#define check_inuse_chunk(M,P)
+#define check_malloced_chunk(M,P,N)
+#define check_mmapped_chunk(M,P)
+#define check_malloc_state(M)
+#define check_top_chunk(M,P)
+
+#else /* DEBUG */
+#define check_free_chunk(M,P) do_check_free_chunk(M,P)
+#define check_inuse_chunk(M,P) do_check_inuse_chunk(M,P)
+#define check_top_chunk(M,P) do_check_top_chunk(M,P)
+#define check_malloced_chunk(M,P,N) do_check_malloced_chunk(M,P,N)
+#define check_mmapped_chunk(M,P) do_check_mmapped_chunk(M,P)
+#define check_malloc_state(M) do_check_malloc_state(M)
+
+static void do_check_any_chunk(mstate m, mchunkptr p);
+static void do_check_top_chunk(mstate m, mchunkptr p);
+static void do_check_mmapped_chunk(mstate m, mchunkptr p);
+static void do_check_inuse_chunk(mstate m, mchunkptr p);
+static void do_check_free_chunk(mstate m, mchunkptr p);
+static void do_check_malloced_chunk(mstate m, void* mem, size_t s);
+static void do_check_tree(mstate m, tchunkptr t);
+static void do_check_treebin(mstate m, bindex_t i);
+static void do_check_smallbin(mstate m, bindex_t i);
+static void do_check_malloc_state(mstate m);
+static int bin_find(mstate m, mchunkptr x);
+static size_t traverse_and_check(mstate m);
+#endif /* DEBUG */
+
+/* ---------------------------- Indexing Bins ---------------------------- */
+
+#define is_small(s) (((s) >> SMALLBIN_SHIFT) < NSMALLBINS)
+#define small_index(s) (bindex_t)((s) >> SMALLBIN_SHIFT)
+#define small_index2size(i) ((i) << SMALLBIN_SHIFT)
+#define MIN_SMALL_INDEX (small_index(MIN_CHUNK_SIZE))
+
+/* addressing by index. See above about smallbin repositioning */
+#define smallbin_at(M, i) ((sbinptr)((char*)&((M)->smallbins[(i)<<1])))
+#define treebin_at(M,i) (&((M)->treebins[i]))
+
+/* assign tree index for size S to variable I. Use x86 asm if possible */
+#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
+#define compute_tree_index(S, I)\
+{\
+ unsigned int X = S >> TREEBIN_SHIFT;\
+ if (X == 0)\
+ I = 0;\
+ else if (X > 0xFFFF)\
+ I = NTREEBINS-1;\
+ else {\
+ unsigned int K = (unsigned) sizeof(X)*__CHAR_BIT__ - 1 - (unsigned) __builtin_clz(X); \
+ I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
+ }\
+}
+
+#elif defined (__INTEL_COMPILER)
+#define compute_tree_index(S, I)\
+{\
+ size_t X = S >> TREEBIN_SHIFT;\
+ if (X == 0)\
+ I = 0;\
+ else if (X > 0xFFFF)\
+ I = NTREEBINS-1;\
+ else {\
+ unsigned int K = _bit_scan_reverse (X); \
+ I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
+ }\
+}
+
+#elif defined(_MSC_VER) && _MSC_VER>=1300
+#define compute_tree_index(S, I)\
+{\
+ size_t X = S >> TREEBIN_SHIFT;\
+ if (X == 0)\
+ I = 0;\
+ else if (X > 0xFFFF)\
+ I = NTREEBINS-1;\
+ else {\
+ unsigned int K;\
+ _BitScanReverse((DWORD *) &K, (DWORD) X);\
+ I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
+ }\
+}
+
+#else /* GNUC */
+#define compute_tree_index(S, I)\
+{\
+ size_t X = S >> TREEBIN_SHIFT;\
+ if (X == 0)\
+ I = 0;\
+ else if (X > 0xFFFF)\
+ I = NTREEBINS-1;\
+ else {\
+ unsigned int Y = (unsigned int)X;\
+ unsigned int N = ((Y - 0x100) >> 16) & 8;\
+ unsigned int K = (((Y <<= N) - 0x1000) >> 16) & 4;\
+ N += K;\
+ N += K = (((Y <<= K) - 0x4000) >> 16) & 2;\
+ K = 14 - N + ((Y <<= K) >> 15);\
+ I = (K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1));\
+ }\
+}
+#endif /* GNUC */
+
+/* Bit representing maximum resolved size in a treebin at i */
+#define bit_for_tree_index(i) \
+ (i == NTREEBINS-1)? (SIZE_T_BITSIZE-1) : (((i) >> 1) + TREEBIN_SHIFT - 2)
+
+/* Shift placing maximum resolved bit in a treebin at i as sign bit */
+#define leftshift_for_tree_index(i) \
+ ((i == NTREEBINS-1)? 0 : \
+ ((SIZE_T_BITSIZE-SIZE_T_ONE) - (((i) >> 1) + TREEBIN_SHIFT - 2)))
+
+/* The size of the smallest chunk held in bin with index i */
+#define minsize_for_tree_index(i) \
+ ((SIZE_T_ONE << (((i) >> 1) + TREEBIN_SHIFT)) | \
+ (((size_t)((i) & SIZE_T_ONE)) << (((i) >> 1) + TREEBIN_SHIFT - 1)))
+
+
+/* ------------------------ Operations on bin maps ----------------------- */
+
+/* bit corresponding to given index */
+#define idx2bit(i) ((binmap_t)(1) << (i))
+
+/* Mark/Clear bits with given index */
+#define mark_smallmap(M,i) ((M)->smallmap |= idx2bit(i))
+#define clear_smallmap(M,i) ((M)->smallmap &= ~idx2bit(i))
+#define smallmap_is_marked(M,i) ((M)->smallmap & idx2bit(i))
+
+#define mark_treemap(M,i) ((M)->treemap |= idx2bit(i))
+#define clear_treemap(M,i) ((M)->treemap &= ~idx2bit(i))
+#define treemap_is_marked(M,i) ((M)->treemap & idx2bit(i))
+
+/* isolate the least set bit of a bitmap */
+#define least_bit(x) ((x) & -(x))
+
+/* mask with all bits to left of least bit of x on */
+#define left_bits(x) ((x<<1) | -(x<<1))
+
+/* mask with all bits to left of or equal to least bit of x on */
+#define same_or_left_bits(x) ((x) | -(x))
+
+/* index corresponding to given bit. Use x86 asm if possible */
+
+#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
+#define compute_bit2idx(X, I)\
+{\
+ unsigned int J;\
+ J = __builtin_ctz(X); \
+ I = (bindex_t)J;\
+}
+
+#elif defined (__INTEL_COMPILER)
+#define compute_bit2idx(X, I)\
+{\
+ unsigned int J;\
+ J = _bit_scan_forward (X); \
+ I = (bindex_t)J;\
+}
+
+#elif defined(_MSC_VER) && _MSC_VER>=1300
+#define compute_bit2idx(X, I)\
+{\
+ unsigned int J;\
+ _BitScanForward((DWORD *) &J, X);\
+ I = (bindex_t)J;\
+}
+
+#elif USE_BUILTIN_FFS
+#define compute_bit2idx(X, I) I = ffs(X)-1
+
+#else
+#define compute_bit2idx(X, I)\
+{\
+ unsigned int Y = X - 1;\
+ unsigned int K = Y >> (16-4) & 16;\
+ unsigned int N = K; Y >>= K;\
+ N += K = Y >> (8-3) & 8; Y >>= K;\
+ N += K = Y >> (4-2) & 4; Y >>= K;\
+ N += K = Y >> (2-1) & 2; Y >>= K;\
+ N += K = Y >> (1-0) & 1; Y >>= K;\
+ I = (bindex_t)(N + Y);\
+}
+#endif /* GNUC */
+
+
+/* ----------------------- Runtime Check Support ------------------------- */
+
+/*
+ For security, the main invariant is that malloc/free/etc never
+ writes to a static address other than malloc_state, unless static
+ malloc_state itself has been corrupted, which cannot occur via
+ malloc (because of these checks). In essence this means that we
+ believe all pointers, sizes, maps etc held in malloc_state, but
+ check all of those linked or offsetted from other embedded data
+ structures. These checks are interspersed with main code in a way
+ that tends to minimize their run-time cost.
+
+ When FOOTERS is defined, in addition to range checking, we also
+ verify footer fields of inuse chunks, which can be used guarantee
+ that the mstate controlling malloc/free is intact. This is a
+ streamlined version of the approach described by William Robertson
+ et al in "Run-time Detection of Heap-based Overflows" LISA'03
+ http://www.usenix.org/events/lisa03/tech/robertson.html The footer
+ of an inuse chunk holds the xor of its mstate and a random seed,
+ that is checked upon calls to free() and realloc(). This is
+ (probabalistically) unguessable from outside the program, but can be
+ computed by any code successfully malloc'ing any chunk, so does not
+ itself provide protection against code that has already broken
+ security through some other means. Unlike Robertson et al, we
+ always dynamically check addresses of all offset chunks (previous,
+ next, etc). This turns out to be cheaper than relying on hashes.
+*/
+
+#if !INSECURE
+/* Check if address a is at least as high as any from MORECORE or MMAP */
+#define ok_address(M, a) ((char*)(a) >= (M)->least_addr)
+/* Check if address of next chunk n is higher than base chunk p */
+#define ok_next(p, n) ((char*)(p) < (char*)(n))
+/* Check if p has inuse status */
+#define ok_inuse(p) is_inuse(p)
+/* Check if p has its pinuse bit on */
+#define ok_pinuse(p) pinuse(p)
+
+#else /* !INSECURE */
+#define ok_address(M, a) (1)
+#define ok_next(b, n) (1)
+#define ok_inuse(p) (1)
+#define ok_pinuse(p) (1)
+#endif /* !INSECURE */
+
+#if (FOOTERS && !INSECURE)
+/* Check if (alleged) mstate m has expected magic field */
+#define ok_magic(M) ((M)->magic == mparams.magic)
+#else /* (FOOTERS && !INSECURE) */
+#define ok_magic(M) (1)
+#endif /* (FOOTERS && !INSECURE) */
+
+/* In gcc, use __builtin_expect to minimize impact of checks */
+#if !INSECURE
+#if defined(__GNUC__) && __GNUC__ >= 3
+#define RTCHECK(e) __builtin_expect(e, 1)
+#else /* GNUC */
+#define RTCHECK(e) (e)
+#endif /* GNUC */
+#else /* !INSECURE */
+#define RTCHECK(e) (1)
+#endif /* !INSECURE */
+
+/* macros to set up inuse chunks with or without footers */
+
+#if !FOOTERS
+
+#define mark_inuse_foot(M,p,s)
+
+/* Macros for setting head/foot of non-mmapped chunks */
+
+/* Set cinuse bit and pinuse bit of next chunk */
+#define set_inuse(M,p,s)\
+ ((p)->head = (((p)->head & PINUSE_BIT)|s|CINUSE_BIT),\
+ ((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT)
+
+/* Set cinuse and pinuse of this chunk and pinuse of next chunk */
+#define set_inuse_and_pinuse(M,p,s)\
+ ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
+ ((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT)
+
+/* Set size, cinuse and pinuse bit of this chunk */
+#define set_size_and_pinuse_of_inuse_chunk(M, p, s)\
+ ((p)->head = (s|PINUSE_BIT|CINUSE_BIT))
+
+#else /* FOOTERS */
+
+/* Set foot of inuse chunk to be xor of mstate and seed */
+#define mark_inuse_foot(M,p,s)\
+ (((mchunkptr)((char*)(p) + (s)))->prev_foot = ((size_t)(M) ^ mparams.magic))
+
+#define get_mstate_for(p)\
+ ((mstate)(((mchunkptr)((char*)(p) +\
+ (chunksize(p))))->prev_foot ^ mparams.magic))
+
+#define set_inuse(M,p,s)\
+ ((p)->head = (((p)->head & PINUSE_BIT)|s|CINUSE_BIT),\
+ (((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT), \
+ mark_inuse_foot(M,p,s))
+
+#define set_inuse_and_pinuse(M,p,s)\
+ ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
+ (((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT),\
+ mark_inuse_foot(M,p,s))
+
+#define set_size_and_pinuse_of_inuse_chunk(M, p, s)\
+ ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
+ mark_inuse_foot(M, p, s))
+
+#endif /* !FOOTERS */
+
+/* ---------------------------- setting mparams -------------------------- */
+
+#if LOCK_AT_FORK
+static void pre_fork(void) { ACQUIRE_LOCK(&(gm)->mutex); }
+static void post_fork_parent(void) { RELEASE_LOCK(&(gm)->mutex); }
+static void post_fork_child(void) { INITIAL_LOCK(&(gm)->mutex); }
+#endif /* LOCK_AT_FORK */
+
+/* Initialize mparams */
+static int init_mparams(void) {
+#ifdef NEED_GLOBAL_LOCK_INIT
+ if (malloc_global_mutex_status <= 0)
+ init_malloc_global_mutex();
+#endif
+
+ ACQUIRE_MALLOC_GLOBAL_LOCK();
+ if (mparams.magic == 0) {
+ size_t magic;
+ size_t psize;
+ size_t gsize;
+
+#ifndef WIN32
+ psize = malloc_getpagesize;
+ gsize = ((DEFAULT_GRANULARITY != 0)? DEFAULT_GRANULARITY : psize);
+#else /* WIN32 */
+ {
+ SYSTEM_INFO system_info;
+ GetSystemInfo(&system_info);
+ psize = system_info.dwPageSize;
+ gsize = ((DEFAULT_GRANULARITY != 0)?
+ DEFAULT_GRANULARITY : system_info.dwAllocationGranularity);
+ }
+#endif /* WIN32 */
+
+ /* Sanity-check configuration:
+ size_t must be unsigned and as wide as pointer type.
+ ints must be at least 4 bytes.
+ alignment must be at least 8.
+ Alignment, min chunk size, and page size must all be powers of 2.
+ */
+ if ((sizeof(size_t) != sizeof(char*)) ||
+ (MAX_SIZE_T < MIN_CHUNK_SIZE) ||
+ (sizeof(int) < 4) ||
+ (MALLOC_ALIGNMENT < (size_t)8U) ||
+ ((MALLOC_ALIGNMENT & (MALLOC_ALIGNMENT-SIZE_T_ONE)) != 0) ||
+ ((MCHUNK_SIZE & (MCHUNK_SIZE-SIZE_T_ONE)) != 0) ||
+ ((gsize & (gsize-SIZE_T_ONE)) != 0) ||
+ ((psize & (psize-SIZE_T_ONE)) != 0))
+ DLM_ABORT;
+ mparams.granularity = gsize;
+ mparams.page_size = psize;
+ mparams.mmap_threshold = DEFAULT_MMAP_THRESHOLD;
+ mparams.trim_threshold = DEFAULT_TRIM_THRESHOLD;
+#if MORECORE_CONTIGUOUS
+ mparams.default_mflags = USE_LOCK_BIT|USE_MMAP_BIT;
+#else /* MORECORE_CONTIGUOUS */
+ mparams.default_mflags = USE_LOCK_BIT|USE_MMAP_BIT|USE_NONCONTIGUOUS_BIT;
+#endif /* MORECORE_CONTIGUOUS */
+
+#if !ONLY_MSPACES
+ /* Set up lock for main malloc area */
+ gm->mflags = mparams.default_mflags;
+ (void)INITIAL_LOCK(&gm->mutex);
+#endif
+#if LOCK_AT_FORK
+ pthread_atfork(&pre_fork, &post_fork_parent, &post_fork_child);
+#endif
+
+ {
+#if USE_DEV_RANDOM
+ int fd;
+ unsigned char buf[sizeof(size_t)];
+ /* Try to use /dev/urandom, else fall back on using time */
+ if ((fd = open("/dev/urandom", O_RDONLY)) >= 0 &&
+ read(fd, buf, sizeof(buf)) == sizeof(buf)) {
+ magic = *((size_t *) buf);
+ close(fd);
+ }
+ else
+#endif /* USE_DEV_RANDOM */
+#ifdef WIN32
+ magic = (size_t)(GetTickCount() ^ (size_t)0x55555555U);
+#elif defined(LACKS_TIME_H)
+ magic = (size_t)&magic ^ (size_t)0x55555555U;
+#else
+ magic = (size_t)(time(0) ^ (size_t)0x55555555U);
+#endif
+ magic |= (size_t)8U; /* ensure nonzero */
+ magic &= ~(size_t)7U; /* improve chances of fault for bad values */
+ /* Until memory modes commonly available, use volatile-write */
+ (*(volatile size_t *)(&(mparams.magic))) = magic;
+ }
+ }
+
+ RELEASE_MALLOC_GLOBAL_LOCK();
+ return 1;
+}
+
+/* support for mallopt */
+static int change_mparam(int param_number, int value) {
+ size_t val;
+ ensure_initialization();
+ val = (value == -1)? MAX_SIZE_T : (size_t)value;
+ switch(param_number) {
+ case M_TRIM_THRESHOLD:
+ mparams.trim_threshold = val;
+ return 1;
+ case M_GRANULARITY:
+ if (val >= mparams.page_size && ((val & (val-1)) == 0)) {
+ mparams.granularity = val;
+ return 1;
+ }
+ else
+ return 0;
+ case M_MMAP_THRESHOLD:
+ mparams.mmap_threshold = val;
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+#if DEBUG
+/* ------------------------- Debugging Support --------------------------- */
+
+/* Check properties of any chunk, whether free, inuse, mmapped etc */
+static void do_check_any_chunk(mstate m, mchunkptr p) {
+ assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
+ assert(ok_address(m, p));
+}
+
+/* Check properties of top chunk */
+static void do_check_top_chunk(mstate m, mchunkptr p) {
+ msegmentptr sp = segment_holding(m, (char*)p);
+ size_t sz = p->head & ~INUSE_BITS; /* third-lowest bit can be set! */
+ assert(sp != 0);
+ assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
+ assert(ok_address(m, p));
+ assert(sz == m->topsize);
+ assert(sz > 0);
+ assert(sz == ((sp->base + sp->size) - (char*)p) - TOP_FOOT_SIZE);
+ assert(pinuse(p));
+ assert(!pinuse(chunk_plus_offset(p, sz)));
+}
+
+/* Check properties of (inuse) mmapped chunks */
+static void do_check_mmapped_chunk(mstate m, mchunkptr p) {
+ size_t sz = chunksize(p);
+ size_t len = (sz + (p->prev_foot) + MMAP_FOOT_PAD);
+ assert(is_mmapped(p));
+ assert(use_mmap(m));
+ assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
+ assert(ok_address(m, p));
+ assert(!is_small(sz));
+ assert((len & (mparams.page_size-SIZE_T_ONE)) == 0);
+ assert(chunk_plus_offset(p, sz)->head == FENCEPOST_HEAD);
+ assert(chunk_plus_offset(p, sz+SIZE_T_SIZE)->head == 0);
+}
+
+/* Check properties of inuse chunks */
+static void do_check_inuse_chunk(mstate m, mchunkptr p) {
+ do_check_any_chunk(m, p);
+ assert(is_inuse(p));
+ assert(next_pinuse(p));
+ /* If not pinuse and not mmapped, previous chunk has OK offset */
+ assert(is_mmapped(p) || pinuse(p) || next_chunk(prev_chunk(p)) == p);
+ if (is_mmapped(p))
+ do_check_mmapped_chunk(m, p);
+}
+
+/* Check properties of free chunks */
+static void do_check_free_chunk(mstate m, mchunkptr p) {
+ size_t sz = chunksize(p);
+ mchunkptr next = chunk_plus_offset(p, sz);
+ do_check_any_chunk(m, p);
+ assert(!is_inuse(p));
+ assert(!next_pinuse(p));
+ assert (!is_mmapped(p));
+ if (p != m->dv && p != m->top) {
+ if (sz >= MIN_CHUNK_SIZE) {
+ assert((sz & CHUNK_ALIGN_MASK) == 0);
+ assert(is_aligned(chunk2mem(p)));
+ assert(next->prev_foot == sz);
+ assert(pinuse(p));
+ assert (next == m->top || is_inuse(next));
+ assert(p->fd->bk == p);
+ assert(p->bk->fd == p);
+ }
+ else /* markers are always of size SIZE_T_SIZE */
+ assert(sz == SIZE_T_SIZE);
+ }
+}
+
+/* Check properties of malloced chunks at the point they are malloced */
+static void do_check_malloced_chunk(mstate m, void* mem, size_t s) {
+ if (mem != 0) {
+ mchunkptr p = mem2chunk(mem);
+ size_t sz = p->head & ~INUSE_BITS;
+ do_check_inuse_chunk(m, p);
+ assert((sz & CHUNK_ALIGN_MASK) == 0);
+ assert(sz >= MIN_CHUNK_SIZE);
+ assert(sz >= s);
+ /* unless mmapped, size is less than MIN_CHUNK_SIZE more than request */
+ assert(is_mmapped(p) || sz < (s + MIN_CHUNK_SIZE));
+ }
+}
+
+/* Check a tree and its subtrees. */
+static void do_check_tree(mstate m, tchunkptr t) {
+ tchunkptr head = 0;
+ tchunkptr u = t;
+ bindex_t tindex = t->index;
+ size_t tsize = chunksize(t);
+ bindex_t idx;
+ compute_tree_index(tsize, idx);
+ assert(tindex == idx);
+ assert(tsize >= MIN_LARGE_SIZE);
+ assert(tsize >= minsize_for_tree_index(idx));
+ assert((idx == NTREEBINS-1) || (tsize < minsize_for_tree_index((idx+1))));
+
+ do { /* traverse through chain of same-sized nodes */
+ do_check_any_chunk(m, ((mchunkptr)u));
+ assert(u->index == tindex);
+ assert(chunksize(u) == tsize);
+ assert(!is_inuse(u));
+ assert(!next_pinuse(u));
+ assert(u->fd->bk == u);
+ assert(u->bk->fd == u);
+ if (u->parent == 0) {
+ assert(u->child[0] == 0);
+ assert(u->child[1] == 0);
+ }
+ else {
+ assert(head == 0); /* only one node on chain has parent */
+ head = u;
+ assert(u->parent != u);
+ assert (u->parent->child[0] == u ||
+ u->parent->child[1] == u ||
+ *((tbinptr*)(u->parent)) == u);
+ if (u->child[0] != 0) {
+ assert(u->child[0]->parent == u);
+ assert(u->child[0] != u);
+ do_check_tree(m, u->child[0]);
+ }
+ if (u->child[1] != 0) {
+ assert(u->child[1]->parent == u);
+ assert(u->child[1] != u);
+ do_check_tree(m, u->child[1]);
+ }
+ if (u->child[0] != 0 && u->child[1] != 0) {
+ assert(chunksize(u->child[0]) < chunksize(u->child[1]));
+ }
+ }
+ u = u->fd;
+ } while (u != t);
+ assert(head != 0);
+}
+
+/* Check all the chunks in a treebin. */
+static void do_check_treebin(mstate m, bindex_t i) {
+ tbinptr* tb = treebin_at(m, i);
+ tchunkptr t = *tb;
+ int empty = (m->treemap & (1U << i)) == 0;
+ if (t == 0)
+ assert(empty);
+ if (!empty)
+ do_check_tree(m, t);
+}
+
+/* Check all the chunks in a smallbin. */
+static void do_check_smallbin(mstate m, bindex_t i) {
+ sbinptr b = smallbin_at(m, i);
+ mchunkptr p = b->bk;
+ unsigned int empty = (m->smallmap & (1U << i)) == 0;
+ if (p == b)
+ assert(empty);
+ if (!empty) {
+ for (; p != b; p = p->bk) {
+ size_t size = chunksize(p);
+ mchunkptr q;
+ /* each chunk claims to be free */
+ do_check_free_chunk(m, p);
+ /* chunk belongs in bin */
+ assert(small_index(size) == i);
+ assert(p->bk == b || chunksize(p->bk) == chunksize(p));
+ /* chunk is followed by an inuse chunk */
+ q = next_chunk(p);
+ if (q->head != FENCEPOST_HEAD)
+ do_check_inuse_chunk(m, q);
+ }
+ }
+}
+
+/* Find x in a bin. Used in other check functions. */
+static int bin_find(mstate m, mchunkptr x) {
+ size_t size = chunksize(x);
+ if (is_small(size)) {
+ bindex_t sidx = small_index(size);
+ sbinptr b = smallbin_at(m, sidx);
+ if (smallmap_is_marked(m, sidx)) {
+ mchunkptr p = b;
+ do {
+ if (p == x)
+ return 1;
+ } while ((p = p->fd) != b);
+ }
+ }
+ else {
+ bindex_t tidx;
+ compute_tree_index(size, tidx);
+ if (treemap_is_marked(m, tidx)) {
+ tchunkptr t = *treebin_at(m, tidx);
+ size_t sizebits = size << leftshift_for_tree_index(tidx);
+ while (t != 0 && chunksize(t) != size) {
+ t = t->child[(sizebits >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1];
+ sizebits <<= 1;
+ }
+ if (t != 0) {
+ tchunkptr u = t;
+ do {
+ if (u == (tchunkptr)x)
+ return 1;
+ } while ((u = u->fd) != t);
+ }
+ }
+ }
+ return 0;
+}
+
+/* Traverse each chunk and check it; return total */
+static size_t traverse_and_check(mstate m) {
+ size_t sum = 0;
+ if (is_initialized(m)) {
+ msegmentptr s = &m->seg;
+ sum += m->topsize + TOP_FOOT_SIZE;
+ while (s != 0) {
+ mchunkptr q = align_as_chunk(s->base);
+ mchunkptr lastq = 0;
+ assert(pinuse(q));
+ while (segment_holds(s, q) &&
+ q != m->top && q->head != FENCEPOST_HEAD) {
+ sum += chunksize(q);
+ if (is_inuse(q)) {
+ assert(!bin_find(m, q));
+ do_check_inuse_chunk(m, q);
+ }
+ else {
+ assert(q == m->dv || bin_find(m, q));
+ assert(lastq == 0 || is_inuse(lastq)); /* Not 2 consecutive free */
+ do_check_free_chunk(m, q);
+ }
+ lastq = q;
+ q = next_chunk(q);
+ }
+ s = s->next;
+ }
+ }
+ return sum;
+}
+
+
+/* Check all properties of malloc_state. */
+static void do_check_malloc_state(mstate m) {
+ bindex_t i;
+ size_t total;
+ /* check bins */
+ for (i = 0; i < NSMALLBINS; ++i)
+ do_check_smallbin(m, i);
+ for (i = 0; i < NTREEBINS; ++i)
+ do_check_treebin(m, i);
+
+ if (m->dvsize != 0) { /* check dv chunk */
+ do_check_any_chunk(m, m->dv);
+ assert(m->dvsize == chunksize(m->dv));
+ assert(m->dvsize >= MIN_CHUNK_SIZE);
+ assert(bin_find(m, m->dv) == 0);
+ }
+
+ if (m->top != 0) { /* check top chunk */
+ do_check_top_chunk(m, m->top);
+ /*assert(m->topsize == chunksize(m->top)); redundant */
+ assert(m->topsize > 0);
+ assert(bin_find(m, m->top) == 0);
+ }
+
+ total = traverse_and_check(m);
+ assert(total <= m->footprint);
+ assert(m->footprint <= m->max_footprint);
+}
+#endif /* DEBUG */
+
+/* ----------------------------- statistics ------------------------------ */
+
+#if !NO_MALLINFO
+static struct mallinfo internal_mallinfo(mstate m) {
+ struct mallinfo nm = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+ ensure_initialization();
+ if (!PREACTION(m)) {
+ check_malloc_state(m);
+ if (is_initialized(m)) {
+ size_t nfree = SIZE_T_ONE; /* top always free */
+ size_t mfree = m->topsize + TOP_FOOT_SIZE;
+ size_t sum = mfree;
+ msegmentptr s = &m->seg;
+ while (s != 0) {
+ mchunkptr q = align_as_chunk(s->base);
+ while (segment_holds(s, q) &&
+ q != m->top && q->head != FENCEPOST_HEAD) {
+ size_t sz = chunksize(q);
+ sum += sz;
+ if (!is_inuse(q)) {
+ mfree += sz;
+ ++nfree;
+ }
+ q = next_chunk(q);
+ }
+ s = s->next;
+ }
+
+ nm.arena = sum;
+ nm.ordblks = nfree;
+ nm.hblkhd = m->footprint - sum;
+ nm.usmblks = m->max_footprint;
+ nm.uordblks = m->footprint - mfree;
+ nm.fordblks = mfree;
+ nm.keepcost = m->topsize;
+ }
+
+ POSTACTION(m);
+ }
+ return nm;
+}
+#endif /* !NO_MALLINFO */
+
+#if !NO_MALLOC_STATS
+static void internal_malloc_stats(mstate m) {
+ ensure_initialization();
+ if (!PREACTION(m)) {
+ size_t maxfp = 0;
+ size_t fp = 0;
+ size_t used = 0;
+ check_malloc_state(m);
+ if (is_initialized(m)) {
+ msegmentptr s = &m->seg;
+ maxfp = m->max_footprint;
+ fp = m->footprint;
+ used = fp - (m->topsize + TOP_FOOT_SIZE);
+
+ while (s != 0) {
+ mchunkptr q = align_as_chunk(s->base);
+ while (segment_holds(s, q) &&
+ q != m->top && q->head != FENCEPOST_HEAD) {
+ if (!is_inuse(q))
+ used -= chunksize(q);
+ q = next_chunk(q);
+ }
+ s = s->next;
+ }
+ }
+ POSTACTION(m); /* drop lock */
+ fprintf(stderr, "max system bytes = %10lu\n", (unsigned long)(maxfp));
+ fprintf(stderr, "system bytes = %10lu\n", (unsigned long)(fp));
+ fprintf(stderr, "in use bytes = %10lu\n", (unsigned long)(used));
+ }
+}
+#endif /* NO_MALLOC_STATS */
+
+/* ----------------------- Operations on smallbins ----------------------- */
+
+/*
+ Various forms of linking and unlinking are defined as macros. Even
+ the ones for trees, which are very long but have very short typical
+ paths. This is ugly but reduces reliance on inlining support of
+ compilers.
+*/
+
+/* Link a free chunk into a smallbin */
+#define insert_small_chunk(M, P, S) {\
+ bindex_t I = small_index(S);\
+ mchunkptr B = smallbin_at(M, I);\
+ mchunkptr F = B;\
+ assert(S >= MIN_CHUNK_SIZE);\
+ if (!smallmap_is_marked(M, I))\
+ mark_smallmap(M, I);\
+ else if (RTCHECK(ok_address(M, B->fd)))\
+ F = B->fd;\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+ B->fd = P;\
+ F->bk = P;\
+ P->fd = F;\
+ P->bk = B;\
+}
+
+/* Unlink a chunk from a smallbin */
+#define unlink_small_chunk(M, P, S) {\
+ mchunkptr F = P->fd;\
+ mchunkptr B = P->bk;\
+ bindex_t I = small_index(S);\
+ assert(P != B);\
+ assert(P != F);\
+ assert(chunksize(P) == small_index2size(I));\
+ if (RTCHECK(F == smallbin_at(M,I) || (ok_address(M, F) && F->bk == P))) { \
+ if (B == F) {\
+ clear_smallmap(M, I);\
+ }\
+ else if (RTCHECK(B == smallbin_at(M,I) ||\
+ (ok_address(M, B) && B->fd == P))) {\
+ F->bk = B;\
+ B->fd = F;\
+ }\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+ }\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+}
+
+/* Unlink the first chunk from a smallbin */
+#define unlink_first_small_chunk(M, B, P, I) {\
+ mchunkptr F = P->fd;\
+ assert(P != B);\
+ assert(P != F);\
+ assert(chunksize(P) == small_index2size(I));\
+ if (B == F) {\
+ clear_smallmap(M, I);\
+ }\
+ else if (RTCHECK(ok_address(M, F) && F->bk == P)) {\
+ F->bk = B;\
+ B->fd = F;\
+ }\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+}
+
+/* Replace dv node, binning the old one */
+/* Used only when dvsize known to be small */
+#define replace_dv(M, P, S) {\
+ size_t DVS = M->dvsize;\
+ assert(is_small(DVS));\
+ if (DVS != 0) {\
+ mchunkptr DV = M->dv;\
+ insert_small_chunk(M, DV, DVS);\
+ }\
+ M->dvsize = S;\
+ M->dv = P;\
+}
+
+/* ------------------------- Operations on trees ------------------------- */
+
+/* Insert chunk into tree */
+#define insert_large_chunk(M, X, S) {\
+ tbinptr* H;\
+ bindex_t I;\
+ compute_tree_index(S, I);\
+ H = treebin_at(M, I);\
+ X->index = I;\
+ X->child[0] = X->child[1] = 0;\
+ if (!treemap_is_marked(M, I)) {\
+ mark_treemap(M, I);\
+ *H = X;\
+ X->parent = (tchunkptr)H;\
+ X->fd = X->bk = X;\
+ }\
+ else {\
+ tchunkptr T = *H;\
+ size_t K = S << leftshift_for_tree_index(I);\
+ for (;;) {\
+ if (chunksize(T) != S) {\
+ tchunkptr* C = &(T->child[(K >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1]);\
+ K <<= 1;\
+ if (*C != 0)\
+ T = *C;\
+ else if (RTCHECK(ok_address(M, C))) {\
+ *C = X;\
+ X->parent = T;\
+ X->fd = X->bk = X;\
+ break;\
+ }\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ break;\
+ }\
+ }\
+ else {\
+ tchunkptr F = T->fd;\
+ if (RTCHECK(ok_address(M, T) && ok_address(M, F))) {\
+ T->fd = F->bk = X;\
+ X->fd = F;\
+ X->bk = T;\
+ X->parent = 0;\
+ break;\
+ }\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ break;\
+ }\
+ }\
+ }\
+ }\
+}
+
+/*
+ Unlink steps:
+
+ 1. If x is a chained node, unlink it from its same-sized fd/bk links
+ and choose its bk node as its replacement.
+ 2. If x was the last node of its size, but not a leaf node, it must
+ be replaced with a leaf node (not merely one with an open left or
+ right), to make sure that lefts and rights of descendents
+ correspond properly to bit masks. We use the rightmost descendent
+ of x. We could use any other leaf, but this is easy to locate and
+ tends to counteract removal of leftmosts elsewhere, and so keeps
+ paths shorter than minimally guaranteed. This doesn't loop much
+ because on average a node in a tree is near the bottom.
+ 3. If x is the base of a chain (i.e., has parent links) relink
+ x's parent and children to x's replacement (or null if none).
+*/
+
+#define unlink_large_chunk(M, X) {\
+ tchunkptr XP = X->parent;\
+ tchunkptr R;\
+ if (X->bk != X) {\
+ tchunkptr F = X->fd;\
+ R = X->bk;\
+ if (RTCHECK(ok_address(M, F) && F->bk == X && R->fd == X)) {\
+ F->bk = R;\
+ R->fd = F;\
+ }\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+ }\
+ else {\
+ tchunkptr* RP;\
+ if (((R = *(RP = &(X->child[1]))) != 0) ||\
+ ((R = *(RP = &(X->child[0]))) != 0)) {\
+ tchunkptr* CP;\
+ while ((*(CP = &(R->child[1])) != 0) ||\
+ (*(CP = &(R->child[0])) != 0)) {\
+ R = *(RP = CP);\
+ }\
+ if (RTCHECK(ok_address(M, RP)))\
+ *RP = 0;\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+ }\
+ }\
+ if (XP != 0) {\
+ tbinptr* H = treebin_at(M, X->index);\
+ if (X == *H) {\
+ if ((*H = R) == 0) \
+ clear_treemap(M, X->index);\
+ }\
+ else if (RTCHECK(ok_address(M, XP))) {\
+ if (XP->child[0] == X) \
+ XP->child[0] = R;\
+ else \
+ XP->child[1] = R;\
+ }\
+ else\
+ CORRUPTION_ERROR_ACTION(M);\
+ if (R != 0) {\
+ if (RTCHECK(ok_address(M, R))) {\
+ tchunkptr C0, C1;\
+ R->parent = XP;\
+ if ((C0 = X->child[0]) != 0) {\
+ if (RTCHECK(ok_address(M, C0))) {\
+ R->child[0] = C0;\
+ C0->parent = R;\
+ }\
+ else\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+ if ((C1 = X->child[1]) != 0) {\
+ if (RTCHECK(ok_address(M, C1))) {\
+ R->child[1] = C1;\
+ C1->parent = R;\
+ }\
+ else\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+ }\
+ else\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+ }\
+}
+
+/* Relays to large vs small bin operations */
+
+#define insert_chunk(M, P, S)\
+ if (is_small(S)) insert_small_chunk(M, P, S)\
+ else { tchunkptr TP = (tchunkptr)(P); insert_large_chunk(M, TP, S); }
+
+#define unlink_chunk(M, P, S)\
+ if (is_small(S)) unlink_small_chunk(M, P, S)\
+ else { tchunkptr TP = (tchunkptr)(P); unlink_large_chunk(M, TP); }
+
+
+/* Relays to internal calls to malloc/free from realloc, memalign etc */
+
+#if ONLY_MSPACES
+#define internal_malloc(m, b) mspace_malloc(m, b)
+#define internal_free(m, mem) mspace_free(m,mem);
+#else /* ONLY_MSPACES */
+#if MSPACES
+#define internal_malloc(m, b)\
+ ((m == gm)? dlmalloc(b) : mspace_malloc(m, b))
+#define internal_free(m, mem)\
+ if (m == gm) dlfree(mem); else mspace_free(m,mem);
+#else /* MSPACES */
+#define internal_malloc(m, b) dlmalloc(b)
+#define internal_free(m, mem) dlfree(mem)
+#endif /* MSPACES */
+#endif /* ONLY_MSPACES */
+
+/* ----------------------- Direct-mmapping chunks ----------------------- */
+
+/*
+ Directly mmapped chunks are set up with an offset to the start of
+ the mmapped region stored in the prev_foot field of the chunk. This
+ allows reconstruction of the required argument to MUNMAP when freed,
+ and also allows adjustment of the returned chunk to meet alignment
+ requirements (especially in memalign).
+*/
+
+/* Malloc using mmap */
+static void* mmap_alloc(mstate m, size_t nb) {
+ size_t mmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
+ if (m->footprint_limit != 0) {
+ size_t fp = m->footprint + mmsize;
+ if (fp <= m->footprint || fp > m->footprint_limit)
+ return 0;
+ }
+ if (mmsize > nb) { /* Check for wrap around 0 */
+ char* mm = (char*)(CALL_DIRECT_MMAP(mmsize));
+ if (mm != CMFAIL) {
+ size_t offset = align_offset(chunk2mem(mm));
+ size_t psize = mmsize - offset - MMAP_FOOT_PAD;
+ mchunkptr p = (mchunkptr)(mm + offset);
+ p->prev_foot = offset;
+ p->head = psize;
+ mark_inuse_foot(m, p, psize);
+ chunk_plus_offset(p, psize)->head = FENCEPOST_HEAD;
+ chunk_plus_offset(p, psize+SIZE_T_SIZE)->head = 0;
+
+ if (m->least_addr == 0 || mm < m->least_addr)
+ m->least_addr = mm;
+ if ((m->footprint += mmsize) > m->max_footprint)
+ m->max_footprint = m->footprint;
+ assert(is_aligned(chunk2mem(p)));
+ check_mmapped_chunk(m, p);
+ return chunk2mem(p);
+ }
+ }
+ return 0;
+}
+
+/* Realloc using mmap */
+static mchunkptr mmap_resize(mstate m, mchunkptr oldp, size_t nb, int flags) {
+ size_t oldsize = chunksize(oldp);
+ (void)flags; /* placate people compiling -Wunused */
+ if (is_small(nb)) /* Can't shrink mmap regions below small size */
+ return 0;
+ /* Keep old chunk if big enough but not too big */
+ if (oldsize >= nb + SIZE_T_SIZE &&
+ (oldsize - nb) <= (mparams.granularity << 1))
+ return oldp;
+ else {
+ size_t offset = oldp->prev_foot;
+ size_t oldmmsize = oldsize + offset + MMAP_FOOT_PAD;
+ size_t newmmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
+ char* cp = (char*)CALL_MREMAP((char*)oldp - offset,
+ oldmmsize, newmmsize, flags);
+ if (cp != CMFAIL) {
+ mchunkptr newp = (mchunkptr)(cp + offset);
+ size_t psize = newmmsize - offset - MMAP_FOOT_PAD;
+ newp->head = psize;
+ mark_inuse_foot(m, newp, psize);
+ chunk_plus_offset(newp, psize)->head = FENCEPOST_HEAD;
+ chunk_plus_offset(newp, psize+SIZE_T_SIZE)->head = 0;
+
+ if (cp < m->least_addr)
+ m->least_addr = cp;
+ if ((m->footprint += newmmsize - oldmmsize) > m->max_footprint)
+ m->max_footprint = m->footprint;
+ check_mmapped_chunk(m, newp);
+ return newp;
+ }
+ }
+ return 0;
+}
+
+
+/* -------------------------- mspace management -------------------------- */
+
+/* Initialize top chunk and its size */
+static void init_top(mstate m, mchunkptr p, size_t psize) {
+ /* Ensure alignment */
+ size_t offset = align_offset(chunk2mem(p));
+ p = (mchunkptr)((char*)p + offset);
+ psize -= offset;
+
+ m->top = p;
+ m->topsize = psize;
+ p->head = psize | PINUSE_BIT;
+ /* set size of fake trailing chunk holding overhead space only once */
+ chunk_plus_offset(p, psize)->head = TOP_FOOT_SIZE;
+ m->trim_check = mparams.trim_threshold; /* reset on each update */
+}
+
+/* Initialize bins for a new mstate that is otherwise zeroed out */
+static void init_bins(mstate m) {
+ /* Establish circular links for smallbins */
+ bindex_t i;
+ for (i = 0; i < NSMALLBINS; ++i) {
+ sbinptr bin = smallbin_at(m,i);
+ bin->fd = bin->bk = bin;
+ }
+}
+
+#if PROCEED_ON_ERROR
+
+/* default corruption action */
+static void reset_on_error(mstate m) {
+ int i;
+ ++malloc_corruption_error_count;
+ /* Reinitialize fields to forget about all memory */
+ m->smallmap = m->treemap = 0;
+ m->dvsize = m->topsize = 0;
+ m->seg.base = 0;
+ m->seg.size = 0;
+ m->seg.next = 0;
+ m->top = m->dv = 0;
+ for (i = 0; i < NTREEBINS; ++i)
+ *treebin_at(m, i) = 0;
+ init_bins(m);
+}
+#endif /* PROCEED_ON_ERROR */
+
+/* Allocate chunk and prepend remainder with chunk in successor base. */
+static void* prepend_alloc(mstate m, char* newbase, char* oldbase,
+ size_t nb) {
+ mchunkptr p = align_as_chunk(newbase);
+ mchunkptr oldfirst = align_as_chunk(oldbase);
+ size_t psize = (char*)oldfirst - (char*)p;
+ mchunkptr q = chunk_plus_offset(p, nb);
+ size_t qsize = psize - nb;
+ set_size_and_pinuse_of_inuse_chunk(m, p, nb);
+
+ assert((char*)oldfirst > (char*)q);
+ assert(pinuse(oldfirst));
+ assert(qsize >= MIN_CHUNK_SIZE);
+
+ /* consolidate remainder with first chunk of old base */
+ if (oldfirst == m->top) {
+ size_t tsize = m->topsize += qsize;
+ m->top = q;
+ q->head = tsize | PINUSE_BIT;
+ check_top_chunk(m, q);
+ }
+ else if (oldfirst == m->dv) {
+ size_t dsize = m->dvsize += qsize;
+ m->dv = q;
+ set_size_and_pinuse_of_free_chunk(q, dsize);
+ }
+ else {
+ if (!is_inuse(oldfirst)) {
+ size_t nsize = chunksize(oldfirst);
+ unlink_chunk(m, oldfirst, nsize);
+ oldfirst = chunk_plus_offset(oldfirst, nsize);
+ qsize += nsize;
+ }
+ set_free_with_pinuse(q, qsize, oldfirst);
+ insert_chunk(m, q, qsize);
+ check_free_chunk(m, q);
+ }
+
+ check_malloced_chunk(m, chunk2mem(p), nb);
+ return chunk2mem(p);
+}
+
+/* Add a segment to hold a new noncontiguous region */
+static void add_segment(mstate m, char* tbase, size_t tsize, flag_t mmapped) {
+ /* Determine locations and sizes of segment, fenceposts, old top */
+ char* old_top = (char*)m->top;
+ msegmentptr oldsp = segment_holding(m, old_top);
+ char* old_end = oldsp->base + oldsp->size;
+ size_t ssize = pad_request(sizeof(struct malloc_segment));
+ char* rawsp = old_end - (ssize + FOUR_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
+ size_t offset = align_offset(chunk2mem(rawsp));
+ char* asp = rawsp + offset;
+ char* csp = (asp < (old_top + MIN_CHUNK_SIZE))? old_top : asp;
+ mchunkptr sp = (mchunkptr)csp;
+ msegmentptr ss = (msegmentptr)(chunk2mem(sp));
+ mchunkptr tnext = chunk_plus_offset(sp, ssize);
+ mchunkptr p = tnext;
+ int nfences = 0;
+
+ /* reset top to new space */
+ init_top(m, (mchunkptr)tbase, tsize - TOP_FOOT_SIZE);
+
+ /* Set up segment record */
+ assert(is_aligned(ss));
+ set_size_and_pinuse_of_inuse_chunk(m, sp, ssize);
+ *ss = m->seg; /* Push current record */
+ m->seg.base = tbase;
+ m->seg.size = tsize;
+ m->seg.sflags = mmapped;
+ m->seg.next = ss;
+
+ /* Insert trailing fenceposts */
+ for (;;) {
+ mchunkptr nextp = chunk_plus_offset(p, SIZE_T_SIZE);
+ p->head = FENCEPOST_HEAD;
+ ++nfences;
+ if ((char*)(&(nextp->head)) < old_end)
+ p = nextp;
+ else
+ break;
+ }
+ assert(nfences >= 2);
+
+ /* Insert the rest of old top into a bin as an ordinary free chunk */
+ if (csp != old_top) {
+ mchunkptr q = (mchunkptr)old_top;
+ size_t psize = csp - old_top;
+ mchunkptr tn = chunk_plus_offset(q, psize);
+ set_free_with_pinuse(q, psize, tn);
+ insert_chunk(m, q, psize);
+ }
+
+ check_top_chunk(m, m->top);
+}
+
+/* -------------------------- System allocation -------------------------- */
+
+/* Get memory from system using MORECORE or MMAP */
+static void* sys_alloc(mstate m, size_t nb) {
+ char* tbase = CMFAIL;
+ size_t tsize = 0;
+ flag_t mmap_flag = 0;
+ size_t asize; /* allocation size */
+
+ ensure_initialization();
+
+ if (use_noexpand(m))
+ return 0;
+
+ /* Directly map large chunks, but only if already initialized */
+ if (use_mmap(m) && nb >= mparams.mmap_threshold && m->topsize != 0) {
+ void* mem = mmap_alloc(m, nb);
+ if (mem != 0)
+ return mem;
+ }
+
+ asize = granularity_align(nb + SYS_ALLOC_PADDING);
+ if (asize <= nb)
+ return 0; /* wraparound */
+ if (m->footprint_limit != 0) {
+ size_t fp = m->footprint + asize;
+ if (fp <= m->footprint || fp > m->footprint_limit)
+ return 0;
+ }
+
+ /*
+ Try getting memory in any of three ways (in most-preferred to
+ least-preferred order):
+ 1. A call to MORECORE that can normally contiguously extend memory.
+ (disabled if not MORECORE_CONTIGUOUS or not HAVE_MORECORE or
+ or main space is mmapped or a previous contiguous call failed)
+ 2. A call to MMAP new space (disabled if not HAVE_MMAP).
+ Note that under the default settings, if MORECORE is unable to
+ fulfill a request, and HAVE_MMAP is true, then mmap is
+ used as a noncontiguous system allocator. This is a useful backup
+ strategy for systems with holes in address spaces -- in this case
+ sbrk cannot contiguously expand the heap, but mmap may be able to
+ find space.
+ 3. A call to MORECORE that cannot usually contiguously extend memory.
+ (disabled if not HAVE_MORECORE)
+
+ In all cases, we need to request enough bytes from system to ensure
+ we can malloc nb bytes upon success, so pad with enough space for
+ top_foot, plus alignment-pad to make sure we don't lose bytes if
+ not on boundary, and round this up to a granularity unit.
+ */
+
+ if (MORECORE_CONTIGUOUS && !use_noncontiguous(m)) {
+ char* br = CMFAIL;
+ size_t ssize = asize; /* sbrk call size */
+ msegmentptr ss = (m->top == 0)? 0 : segment_holding(m, (char*)m->top);
+ ACQUIRE_MALLOC_GLOBAL_LOCK();
+
+ if (ss == 0) { /* First time through or recovery */
+ char* base = (char*)CALL_MORECORE(0);
+ if (base != CMFAIL) {
+ size_t fp;
+ /* Adjust to end on a page boundary */
+ if (!is_page_aligned(base))
+ ssize += (page_align((size_t)base) - (size_t)base);
+ fp = m->footprint + ssize; /* recheck limits */
+ if (ssize > nb && ssize < HALF_MAX_SIZE_T &&
+ (m->footprint_limit == 0 ||
+ (fp > m->footprint && fp <= m->footprint_limit)) &&
+ (br = (char*)(CALL_MORECORE(ssize))) == base) {
+ tbase = base;
+ tsize = ssize;
+ }
+ }
+ }
+ else {
+ /* Subtract out existing available top space from MORECORE request. */
+ ssize = granularity_align(nb - m->topsize + SYS_ALLOC_PADDING);
+ /* Use mem here only if it did continuously extend old space */
+ if (ssize < HALF_MAX_SIZE_T &&
+ (br = (char*)(CALL_MORECORE(ssize))) == ss->base+ss->size) {
+ tbase = br;
+ tsize = ssize;
+ }
+ }
+
+ if (tbase == CMFAIL) { /* Cope with partial failure */
+ if (br != CMFAIL) { /* Try to use/extend the space we did get */
+ if (ssize < HALF_MAX_SIZE_T &&
+ ssize < nb + SYS_ALLOC_PADDING) {
+ size_t esize = granularity_align(nb + SYS_ALLOC_PADDING - ssize);
+ if (esize < HALF_MAX_SIZE_T) {
+ char* end = (char*)CALL_MORECORE(esize);
+ if (end != CMFAIL)
+ ssize += esize;
+ else { /* Can't use; try to release */
+ (void) CALL_MORECORE(-ssize);
+ br = CMFAIL;
+ }
+ }
+ }
+ }
+ if (br != CMFAIL) { /* Use the space we did get */
+ tbase = br;
+ tsize = ssize;
+ }
+ else
+ disable_contiguous(m); /* Don't try contiguous path in the future */
+ }
+
+ RELEASE_MALLOC_GLOBAL_LOCK();
+ }
+
+ if (HAVE_MMAP && tbase == CMFAIL) { /* Try MMAP */
+ char* mp = (char*)(CALL_MMAP(asize));
+ if (mp != CMFAIL) {
+ tbase = mp;
+ tsize = asize;
+ mmap_flag = USE_MMAP_BIT;
+ }
+ }
+
+ if (HAVE_MORECORE && tbase == CMFAIL) { /* Try noncontiguous MORECORE */
+ if (asize < HALF_MAX_SIZE_T) {
+ char* br = CMFAIL;
+ char* end = CMFAIL;
+ ACQUIRE_MALLOC_GLOBAL_LOCK();
+ br = (char*)(CALL_MORECORE(asize));
+ end = (char*)(CALL_MORECORE(0));
+ RELEASE_MALLOC_GLOBAL_LOCK();
+ if (br != CMFAIL && end != CMFAIL && br < end) {
+ size_t ssize = end - br;
+ if (ssize > nb + TOP_FOOT_SIZE) {
+ tbase = br;
+ tsize = ssize;
+ }
+ }
+ }
+ }
+
+ if (tbase != CMFAIL) {
+
+ if ((m->footprint += tsize) > m->max_footprint)
+ m->max_footprint = m->footprint;
+
+ if (!is_initialized(m)) { /* first-time initialization */
+ if (m->least_addr == 0 || tbase < m->least_addr)
+ m->least_addr = tbase;
+ m->seg.base = tbase;
+ m->seg.size = tsize;
+ m->seg.sflags = mmap_flag;
+ m->magic = mparams.magic;
+ m->release_checks = MAX_RELEASE_CHECK_RATE;
+ init_bins(m);
+#if !ONLY_MSPACES
+ if (is_global(m))
+ init_top(m, (mchunkptr)tbase, tsize - TOP_FOOT_SIZE);
+ else
+#endif
+ {
+ /* Offset top by embedded malloc_state */
+ mchunkptr mn = next_chunk(mem2chunk(m));
+ init_top(m, mn, (size_t)((tbase + tsize) - (char*)mn) -TOP_FOOT_SIZE);
+ }
+ }
+
+ else {
+ /* Try to merge with an existing segment */
+ msegmentptr sp = &m->seg;
+ /* Only consider most recent segment if traversal suppressed */
+ while (sp != 0 && tbase != sp->base + sp->size)
+ sp = (NO_SEGMENT_TRAVERSAL) ? 0 : sp->next;
+ if (sp != 0 &&
+ !is_extern_segment(sp) &&
+ (sp->sflags & USE_MMAP_BIT) == mmap_flag &&
+ segment_holds(sp, m->top)) { /* append */
+ sp->size += tsize;
+ init_top(m, m->top, m->topsize + tsize);
+ }
+ else {
+ if (tbase < m->least_addr)
+ m->least_addr = tbase;
+ sp = &m->seg;
+ while (sp != 0 && sp->base != tbase + tsize)
+ sp = (NO_SEGMENT_TRAVERSAL) ? 0 : sp->next;
+ if (sp != 0 &&
+ !is_extern_segment(sp) &&
+ (sp->sflags & USE_MMAP_BIT) == mmap_flag) {
+ char* oldbase = sp->base;
+ sp->base = tbase;
+ sp->size += tsize;
+ return prepend_alloc(m, tbase, oldbase, nb);
+ }
+ else
+ add_segment(m, tbase, tsize, mmap_flag);
+ }
+ }
+
+ if (nb < m->topsize) { /* Allocate from new or extended top space */
+ size_t rsize = m->topsize -= nb;
+ mchunkptr p = m->top;
+ mchunkptr r = m->top = chunk_plus_offset(p, nb);
+ r->head = rsize | PINUSE_BIT;
+ set_size_and_pinuse_of_inuse_chunk(m, p, nb);
+ check_top_chunk(m, m->top);
+ check_malloced_chunk(m, chunk2mem(p), nb);
+ return chunk2mem(p);
+ }
+ }
+
+ MALLOC_FAILURE_ACTION;
+ return 0;
+}
+
+/* ----------------------- system deallocation -------------------------- */
+
+/* Unmap and unlink any mmapped segments that don't contain used chunks */
+static size_t release_unused_segments(mstate m) {
+ size_t released = 0;
+ int nsegs = 0;
+ msegmentptr pred = &m->seg;
+ msegmentptr sp = pred->next;
+ while (sp != 0) {
+ char* base = sp->base;
+ size_t size = sp->size;
+ msegmentptr next = sp->next;
+ ++nsegs;
+ if (is_mmapped_segment(sp) && !is_extern_segment(sp)) {
+ mchunkptr p = align_as_chunk(base);
+ size_t psize = chunksize(p);
+ /* Can unmap if first chunk holds entire segment and not pinned */
+ if (!is_inuse(p) && (char*)p + psize >= base + size - TOP_FOOT_SIZE) {
+ tchunkptr tp = (tchunkptr)p;
+ assert(segment_holds(sp, (char*)sp));
+ if (p == m->dv) {
+ m->dv = 0;
+ m->dvsize = 0;
+ }
+ else {
+ unlink_large_chunk(m, tp);
+ }
+ if (CALL_MUNMAP(base, size) == 0) {
+ released += size;
+ m->footprint -= size;
+ /* unlink obsoleted record */
+ sp = pred;
+ sp->next = next;
+ }
+ else { /* back out if cannot unmap */
+ insert_large_chunk(m, tp, psize);
+ }
+ }
+ }
+ if (NO_SEGMENT_TRAVERSAL) /* scan only first segment */
+ break;
+ pred = sp;
+ sp = next;
+ }
+ /* Reset check counter */
+ m->release_checks = (((size_t) nsegs > (size_t) MAX_RELEASE_CHECK_RATE)?
+ (size_t) nsegs : (size_t) MAX_RELEASE_CHECK_RATE);
+ return released;
+}
+
+static int sys_trim(mstate m, size_t pad) {
+ size_t released = 0;
+ ensure_initialization();
+ if (pad < MAX_REQUEST && is_initialized(m)) {
+ pad += TOP_FOOT_SIZE; /* ensure enough room for segment overhead */
+
+ if (m->topsize > pad) {
+ /* Shrink top space in granularity-size units, keeping at least one */
+ size_t unit = mparams.granularity;
+ size_t extra = ((m->topsize - pad + (unit - SIZE_T_ONE)) / unit -
+ SIZE_T_ONE) * unit;
+ msegmentptr sp = segment_holding(m, (char*)m->top);
+
+ if (!is_extern_segment(sp)) {
+ if (is_mmapped_segment(sp)) {
+ if (HAVE_MMAP &&
+ sp->size >= extra &&
+ !has_segment_link(m, sp)) { /* can't shrink if pinned */
+ size_t newsize = sp->size - extra;
+ (void)newsize; /* placate people compiling -Wunused-variable */
+ /* Prefer mremap, fall back to munmap */
+ if ((CALL_MREMAP(sp->base, sp->size, newsize, 0) != MFAIL) ||
+ (CALL_MUNMAP(sp->base + newsize, extra) == 0)) {
+ released = extra;
+ }
+ }
+ }
+ else if (HAVE_MORECORE) {
+ if (extra >= HALF_MAX_SIZE_T) /* Avoid wrapping negative */
+ extra = (HALF_MAX_SIZE_T) + SIZE_T_ONE - unit;
+ ACQUIRE_MALLOC_GLOBAL_LOCK();
+ {
+ /* Make sure end of memory is where we last set it. */
+ char* old_br = (char*)(CALL_MORECORE(0));
+ if (old_br == sp->base + sp->size) {
+ char* rel_br = (char*)(CALL_MORECORE(-extra));
+ char* new_br = (char*)(CALL_MORECORE(0));
+ if (rel_br != CMFAIL && new_br < old_br)
+ released = old_br - new_br;
+ }
+ }
+ RELEASE_MALLOC_GLOBAL_LOCK();
+ }
+ }
+
+ if (released != 0) {
+ sp->size -= released;
+ m->footprint -= released;
+ init_top(m, m->top, m->topsize - released);
+ check_top_chunk(m, m->top);
+ }
+ }
+
+ /* Unmap any unused mmapped segments */
+ if (HAVE_MMAP)
+ released += release_unused_segments(m);
+
+ /* On failure, disable autotrim to avoid repeated failed future calls */
+ if (released == 0 && m->topsize > m->trim_check)
+ m->trim_check = MAX_SIZE_T;
+ }
+
+ return (released != 0)? 1 : 0;
+}
+
+/* Consolidate and bin a chunk. Differs from exported versions
+ of free mainly in that the chunk need not be marked as inuse.
+*/
+static void dispose_chunk(mstate m, mchunkptr p, size_t psize) {
+ mchunkptr next = chunk_plus_offset(p, psize);
+ if (!pinuse(p)) {
+ mchunkptr prev;
+ size_t prevsize = p->prev_foot;
+ if (is_mmapped(p)) {
+ psize += prevsize + MMAP_FOOT_PAD;
+ if (CALL_MUNMAP((char*)p - prevsize, psize) == 0)
+ m->footprint -= psize;
+ return;
+ }
+ prev = chunk_minus_offset(p, prevsize);
+ psize += prevsize;
+ p = prev;
+ if (RTCHECK(ok_address(m, prev))) { /* consolidate backward */
+ if (p != m->dv) {
+ unlink_chunk(m, p, prevsize);
+ }
+ else if ((next->head & INUSE_BITS) == INUSE_BITS) {
+ m->dvsize = psize;
+ set_free_with_pinuse(p, psize, next);
+ return;
+ }
+ }
+ else {
+ CORRUPTION_ERROR_ACTION(m);
+ return;
+ }
+ }
+ if (RTCHECK(ok_address(m, next))) {
+ if (!cinuse(next)) { /* consolidate forward */
+ if (next == m->top) {
+ size_t tsize = m->topsize += psize;
+ m->top = p;
+ p->head = tsize | PINUSE_BIT;
+ if (p == m->dv) {
+ m->dv = 0;
+ m->dvsize = 0;
+ }
+ return;
+ }
+ else if (next == m->dv) {
+ size_t dsize = m->dvsize += psize;
+ m->dv = p;
+ set_size_and_pinuse_of_free_chunk(p, dsize);
+ return;
+ }
+ else {
+ size_t nsize = chunksize(next);
+ psize += nsize;
+ unlink_chunk(m, next, nsize);
+ set_size_and_pinuse_of_free_chunk(p, psize);
+ if (p == m->dv) {
+ m->dvsize = psize;
+ return;
+ }
+ }
+ }
+ else {
+ set_free_with_pinuse(p, psize, next);
+ }
+ insert_chunk(m, p, psize);
+ }
+ else {
+ CORRUPTION_ERROR_ACTION(m);
+ }
+}
+
+/* ---------------------------- malloc --------------------------- */
+
+/* allocate a large request from the best fitting chunk in a treebin */
+static void* tmalloc_large(mstate m, size_t nb) {
+ tchunkptr v = 0;
+ size_t rsize = -nb; /* Unsigned negation */
+ tchunkptr t;
+ bindex_t idx;
+ compute_tree_index(nb, idx);
+ if ((t = *treebin_at(m, idx)) != 0) {
+ /* Traverse tree for this bin looking for node with size == nb */
+ size_t sizebits = nb << leftshift_for_tree_index(idx);
+ tchunkptr rst = 0; /* The deepest untaken right subtree */
+ for (;;) {
+ tchunkptr rt;
+ size_t trem = chunksize(t) - nb;
+ if (trem < rsize) {
+ v = t;
+ if ((rsize = trem) == 0)
+ break;
+ }
+ rt = t->child[1];
+ t = t->child[(sizebits >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1];
+ if (rt != 0 && rt != t)
+ rst = rt;
+ if (t == 0) {
+ t = rst; /* set t to least subtree holding sizes > nb */
+ break;
+ }
+ sizebits <<= 1;
+ }
+ }
+ if (t == 0 && v == 0) { /* set t to root of next non-empty treebin */
+ binmap_t leftbits = left_bits(idx2bit(idx)) & m->treemap;
+ if (leftbits != 0) {
+ bindex_t i;
+ binmap_t leastbit = least_bit(leftbits);
+ compute_bit2idx(leastbit, i);
+ t = *treebin_at(m, i);
+ }
+ }
+
+ while (t != 0) { /* find smallest of tree or subtree */
+ size_t trem = chunksize(t) - nb;
+ if (trem < rsize) {
+ rsize = trem;
+ v = t;
+ }
+ t = leftmost_child(t);
+ }
+
+ /* If dv is a better fit, return 0 so malloc will use it */
+ if (v != 0 && rsize < (size_t)(m->dvsize - nb)) {
+ if (RTCHECK(ok_address(m, v))) { /* split */
+ mchunkptr r = chunk_plus_offset(v, nb);
+ assert(chunksize(v) == rsize + nb);
+ if (RTCHECK(ok_next(v, r))) {
+ unlink_large_chunk(m, v);
+ if (rsize < MIN_CHUNK_SIZE)
+ set_inuse_and_pinuse(m, v, (rsize + nb));
+ else {
+ set_size_and_pinuse_of_inuse_chunk(m, v, nb);
+ set_size_and_pinuse_of_free_chunk(r, rsize);
+ insert_chunk(m, r, rsize);
+ }
+ return chunk2mem(v);
+ }
+ }
+ CORRUPTION_ERROR_ACTION(m);
+ }
+ return 0;
+}
+
+/* allocate a small request from the best fitting chunk in a treebin */
+static void* tmalloc_small(mstate m, size_t nb) {
+ tchunkptr t, v;
+ size_t rsize;
+ bindex_t i;
+ binmap_t leastbit = least_bit(m->treemap);
+ compute_bit2idx(leastbit, i);
+ v = t = *treebin_at(m, i);
+ rsize = chunksize(t) - nb;
+
+ while ((t = leftmost_child(t)) != 0) {
+ size_t trem = chunksize(t) - nb;
+ if (trem < rsize) {
+ rsize = trem;
+ v = t;
+ }
+ }
+
+ if (RTCHECK(ok_address(m, v))) {
+ mchunkptr r = chunk_plus_offset(v, nb);
+ assert(chunksize(v) == rsize + nb);
+ if (RTCHECK(ok_next(v, r))) {
+ unlink_large_chunk(m, v);
+ if (rsize < MIN_CHUNK_SIZE)
+ set_inuse_and_pinuse(m, v, (rsize + nb));
+ else {
+ set_size_and_pinuse_of_inuse_chunk(m, v, nb);
+ set_size_and_pinuse_of_free_chunk(r, rsize);
+ replace_dv(m, r, rsize);
+ }
+ return chunk2mem(v);
+ }
+ }
+
+ CORRUPTION_ERROR_ACTION(m);
+ return 0;
+}
+
+#if !ONLY_MSPACES
+
+void* dlmalloc(size_t bytes) {
+ /*
+ Basic algorithm:
+ If a small request (< 256 bytes minus per-chunk overhead):
+ 1. If one exists, use a remainderless chunk in associated smallbin.
+ (Remainderless means that there are too few excess bytes to
+ represent as a chunk.)
+ 2. If it is big enough, use the dv chunk, which is normally the
+ chunk adjacent to the one used for the most recent small request.
+ 3. If one exists, split the smallest available chunk in a bin,
+ saving remainder in dv.
+ 4. If it is big enough, use the top chunk.
+ 5. If available, get memory from system and use it
+ Otherwise, for a large request:
+ 1. Find the smallest available binned chunk that fits, and use it
+ if it is better fitting than dv chunk, splitting if necessary.
+ 2. If better fitting than any binned chunk, use the dv chunk.
+ 3. If it is big enough, use the top chunk.
+ 4. If request size >= mmap threshold, try to directly mmap this chunk.
+ 5. If available, get memory from system and use it
+
+ The ugly goto's here ensure that postaction occurs along all paths.
+ */
+
+#if USE_LOCKS
+ ensure_initialization(); /* initialize in sys_alloc if not using locks */
+#endif
+
+ if (!PREACTION(gm)) {
+ void* mem;
+ size_t nb;
+ if (bytes <= MAX_SMALL_REQUEST) {
+ bindex_t idx;
+ binmap_t smallbits;
+ nb = (bytes < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(bytes);
+ idx = small_index(nb);
+ smallbits = gm->smallmap >> idx;
+
+ if ((smallbits & 0x3U) != 0) { /* Remainderless fit to a smallbin. */
+ mchunkptr b, p;
+ idx += ~smallbits & 1; /* Uses next bin if idx empty */
+ b = smallbin_at(gm, idx);
+ p = b->fd;
+ assert(chunksize(p) == small_index2size(idx));
+ unlink_first_small_chunk(gm, b, p, idx);
+ set_inuse_and_pinuse(gm, p, small_index2size(idx));
+ mem = chunk2mem(p);
+ check_malloced_chunk(gm, mem, nb);
+ goto postaction;
+ }
+
+ else if (nb > gm->dvsize) {
+ if (smallbits != 0) { /* Use chunk in next nonempty smallbin */
+ mchunkptr b, p, r;
+ size_t rsize;
+ bindex_t i;
+ binmap_t leftbits = (smallbits << idx) & left_bits(idx2bit(idx));
+ binmap_t leastbit = least_bit(leftbits);
+ compute_bit2idx(leastbit, i);
+ b = smallbin_at(gm, i);
+ p = b->fd;
+ assert(chunksize(p) == small_index2size(i));
+ unlink_first_small_chunk(gm, b, p, i);
+ rsize = small_index2size(i) - nb;
+ /* Fit here cannot be remainderless if 4byte sizes */
+ if (SIZE_T_SIZE != 4 && rsize < MIN_CHUNK_SIZE)
+ set_inuse_and_pinuse(gm, p, small_index2size(i));
+ else {
+ set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
+ r = chunk_plus_offset(p, nb);
+ set_size_and_pinuse_of_free_chunk(r, rsize);
+ replace_dv(gm, r, rsize);
+ }
+ mem = chunk2mem(p);
+ check_malloced_chunk(gm, mem, nb);
+ goto postaction;
+ }
+
+ else if (gm->treemap != 0 && (mem = tmalloc_small(gm, nb)) != 0) {
+ check_malloced_chunk(gm, mem, nb);
+ goto postaction;
+ }
+ }
+ }
+ else if (bytes >= MAX_REQUEST)
+ nb = MAX_SIZE_T; /* Too big to allocate. Force failure (in sys alloc) */
+ else {
+ nb = pad_request(bytes);
+ if (gm->treemap != 0 && (mem = tmalloc_large(gm, nb)) != 0) {
+ check_malloced_chunk(gm, mem, nb);
+ goto postaction;
+ }
+ }
+
+ if (nb <= gm->dvsize) {
+ size_t rsize = gm->dvsize - nb;
+ mchunkptr p = gm->dv;
+ if (rsize >= MIN_CHUNK_SIZE) { /* split dv */
+ mchunkptr r = gm->dv = chunk_plus_offset(p, nb);
+ gm->dvsize = rsize;
+ set_size_and_pinuse_of_free_chunk(r, rsize);
+ set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
+ }
+ else { /* exhaust dv */
+ size_t dvs = gm->dvsize;
+ gm->dvsize = 0;
+ gm->dv = 0;
+ set_inuse_and_pinuse(gm, p, dvs);
+ }
+ mem = chunk2mem(p);
+ check_malloced_chunk(gm, mem, nb);
+ goto postaction;
+ }
+
+ else if (nb < gm->topsize) { /* Split top */
+ size_t rsize = gm->topsize -= nb;
+ mchunkptr p = gm->top;
+ mchunkptr r = gm->top = chunk_plus_offset(p, nb);
+ r->head = rsize | PINUSE_BIT;
+ set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
+ mem = chunk2mem(p);
+ check_top_chunk(gm, gm->top);
+ check_malloced_chunk(gm, mem, nb);
+ goto postaction;
+ }
+
+ mem = sys_alloc(gm, nb);
+
+ postaction:
+ POSTACTION(gm);
+ return mem;
+ }
+
+ return 0;
+}
+
+/* ---------------------------- free --------------------------- */
+
+void dlfree(void* mem) {
+ /*
+ Consolidate freed chunks with preceeding or succeeding bordering
+ free chunks, if they exist, and then place in a bin. Intermixed
+ with special cases for top, dv, mmapped chunks, and usage errors.
+ */
+
+ if (mem != 0) {
+ mchunkptr p = mem2chunk(mem);
+#if FOOTERS
+ mstate fm = get_mstate_for(p);
+ if (!ok_magic(fm)) {
+ USAGE_ERROR_ACTION(fm, p);
+ return;
+ }
+#else /* FOOTERS */
+#define fm gm
+#endif /* FOOTERS */
+ if (!PREACTION(fm)) {
+ check_inuse_chunk(fm, p);
+ if (RTCHECK(ok_address(fm, p) && ok_inuse(p))) {
+ size_t psize = chunksize(p);
+ mchunkptr next = chunk_plus_offset(p, psize);
+ if (!pinuse(p)) {
+ size_t prevsize = p->prev_foot;
+ if (is_mmapped(p)) {
+ psize += prevsize + MMAP_FOOT_PAD;
+ if (CALL_MUNMAP((char*)p - prevsize, psize) == 0)
+ fm->footprint -= psize;
+ goto postaction;
+ }
+ else {
+ mchunkptr prev = chunk_minus_offset(p, prevsize);
+ psize += prevsize;
+ p = prev;
+ if (RTCHECK(ok_address(fm, prev))) { /* consolidate backward */
+ if (p != fm->dv) {
+ unlink_chunk(fm, p, prevsize);
+ }
+ else if ((next->head & INUSE_BITS) == INUSE_BITS) {
+ fm->dvsize = psize;
+ set_free_with_pinuse(p, psize, next);
+ goto postaction;
+ }
+ }
+ else
+ goto erroraction;
+ }
+ }
+
+ if (RTCHECK(ok_next(p, next) && ok_pinuse(next))) {
+ if (!cinuse(next)) { /* consolidate forward */
+ if (next == fm->top) {
+ size_t tsize = fm->topsize += psize;
+ fm->top = p;
+ p->head = tsize | PINUSE_BIT;
+ if (p == fm->dv) {
+ fm->dv = 0;
+ fm->dvsize = 0;
+ }
+ if (should_trim(fm, tsize))
+ sys_trim(fm, 0);
+ goto postaction;
+ }
+ else if (next == fm->dv) {
+ size_t dsize = fm->dvsize += psize;
+ fm->dv = p;
+ set_size_and_pinuse_of_free_chunk(p, dsize);
+ goto postaction;
+ }
+ else {
+ size_t nsize = chunksize(next);
+ psize += nsize;
+ unlink_chunk(fm, next, nsize);
+ set_size_and_pinuse_of_free_chunk(p, psize);
+ if (p == fm->dv) {
+ fm->dvsize = psize;
+ goto postaction;
+ }
+ }
+ }
+ else
+ set_free_with_pinuse(p, psize, next);
+
+ if (is_small(psize)) {
+ insert_small_chunk(fm, p, psize);
+ check_free_chunk(fm, p);
+ }
+ else {
+ tchunkptr tp = (tchunkptr)p;
+ insert_large_chunk(fm, tp, psize);
+ check_free_chunk(fm, p);
+ if (--fm->release_checks == 0)
+ release_unused_segments(fm);
+ }
+ goto postaction;
+ }
+ }
+ erroraction:
+ USAGE_ERROR_ACTION(fm, p);
+ postaction:
+ POSTACTION(fm);
+ }
+ }
+#if !FOOTERS
+#undef fm
+#endif /* FOOTERS */
+}
+
+void* dlcalloc(size_t n_elements, size_t elem_size) {
+ void* mem;
+ size_t req = 0;
+ if (n_elements != 0) {
+ req = n_elements * elem_size;
+ if (((n_elements | elem_size) & ~(size_t)0xffff) &&
+ (req / n_elements != elem_size))
+ req = MAX_SIZE_T; /* force downstream failure on overflow */
+ }
+ mem = dlmalloc(req);
+ if (mem != 0 && calloc_must_clear(mem2chunk(mem)))
+ memset(mem, 0, req);
+ return mem;
+}
+
+#endif /* !ONLY_MSPACES */
+
+/* ------------ Internal support for realloc, memalign, etc -------------- */
+
+/* Try to realloc; only in-place unless can_move true */
+static mchunkptr try_realloc_chunk(mstate m, mchunkptr p, size_t nb,
+ int can_move) {
+ mchunkptr newp = 0;
+ size_t oldsize = chunksize(p);
+ mchunkptr next = chunk_plus_offset(p, oldsize);
+ if (RTCHECK(ok_address(m, p) && ok_inuse(p) &&
+ ok_next(p, next) && ok_pinuse(next))) {
+ if (is_mmapped(p)) {
+ newp = mmap_resize(m, p, nb, can_move);
+ }
+ else if (oldsize >= nb) { /* already big enough */
+ size_t rsize = oldsize - nb;
+ if (rsize >= MIN_CHUNK_SIZE) { /* split off remainder */
+ mchunkptr r = chunk_plus_offset(p, nb);
+ set_inuse(m, p, nb);
+ set_inuse(m, r, rsize);
+ dispose_chunk(m, r, rsize);
+ }
+ newp = p;
+ }
+ else if (next == m->top) { /* extend into top */
+ if (oldsize + m->topsize > nb) {
+ size_t newsize = oldsize + m->topsize;
+ size_t newtopsize = newsize - nb;
+ mchunkptr newtop = chunk_plus_offset(p, nb);
+ set_inuse(m, p, nb);
+ newtop->head = newtopsize |PINUSE_BIT;
+ m->top = newtop;
+ m->topsize = newtopsize;
+ newp = p;
+ }
+ }
+ else if (next == m->dv) { /* extend into dv */
+ size_t dvs = m->dvsize;
+ if (oldsize + dvs >= nb) {
+ size_t dsize = oldsize + dvs - nb;
+ if (dsize >= MIN_CHUNK_SIZE) {
+ mchunkptr r = chunk_plus_offset(p, nb);
+ mchunkptr n = chunk_plus_offset(r, dsize);
+ set_inuse(m, p, nb);
+ set_size_and_pinuse_of_free_chunk(r, dsize);
+ clear_pinuse(n);
+ m->dvsize = dsize;
+ m->dv = r;
+ }
+ else { /* exhaust dv */
+ size_t newsize = oldsize + dvs;
+ set_inuse(m, p, newsize);
+ m->dvsize = 0;
+ m->dv = 0;
+ }
+ newp = p;
+ }
+ }
+ else if (!cinuse(next)) { /* extend into next free chunk */
+ size_t nextsize = chunksize(next);
+ if (oldsize + nextsize >= nb) {
+ size_t rsize = oldsize + nextsize - nb;
+ unlink_chunk(m, next, nextsize);
+ if (rsize < MIN_CHUNK_SIZE) {
+ size_t newsize = oldsize + nextsize;
+ set_inuse(m, p, newsize);
+ }
+ else {
+ mchunkptr r = chunk_plus_offset(p, nb);
+ set_inuse(m, p, nb);
+ set_inuse(m, r, rsize);
+ dispose_chunk(m, r, rsize);
+ }
+ newp = p;
+ }
+ }
+ }
+ else {
+ USAGE_ERROR_ACTION(m, chunk2mem(p));
+ }
+ return newp;
+}
+
+static void* internal_memalign(mstate m, size_t alignment, size_t bytes) {
+ void* mem = 0;
+ if (alignment < MIN_CHUNK_SIZE) /* must be at least a minimum chunk size */
+ alignment = MIN_CHUNK_SIZE;
+ if ((alignment & (alignment-SIZE_T_ONE)) != 0) {/* Ensure a power of 2 */
+ size_t a = MALLOC_ALIGNMENT << 1;
+ while (a < alignment) a <<= 1;
+ alignment = a;
+ }
+ if (bytes >= MAX_REQUEST - alignment) {
+ if (m != 0) { /* Test isn't needed but avoids compiler warning */
+ MALLOC_FAILURE_ACTION;
+ }
+ }
+ else {
+ size_t nb = request2size(bytes);
+ size_t req = nb + alignment + MIN_CHUNK_SIZE - CHUNK_OVERHEAD;
+ mem = internal_malloc(m, req);
+ if (mem != 0) {
+ mchunkptr p = mem2chunk(mem);
+ if (PREACTION(m))
+ return 0;
+ if ((((size_t)(mem)) & (alignment - 1)) != 0) { /* misaligned */
+ /*
+ Find an aligned spot inside chunk. Since we need to give
+ back leading space in a chunk of at least MIN_CHUNK_SIZE, if
+ the first calculation places us at a spot with less than
+ MIN_CHUNK_SIZE leader, we can move to the next aligned spot.
+ We've allocated enough total room so that this is always
+ possible.
+ */
+ char* br = (char*)mem2chunk((size_t)(((size_t)((char*)mem + alignment -
+ SIZE_T_ONE)) &
+ -alignment));
+ char* pos = ((size_t)(br - (char*)(p)) >= MIN_CHUNK_SIZE)?
+ br : br+alignment;
+ mchunkptr newp = (mchunkptr)pos;
+ size_t leadsize = pos - (char*)(p);
+ size_t newsize = chunksize(p) - leadsize;
+
+ if (is_mmapped(p)) { /* For mmapped chunks, just adjust offset */
+ newp->prev_foot = p->prev_foot + leadsize;
+ newp->head = newsize;
+ }
+ else { /* Otherwise, give back leader, use the rest */
+ set_inuse(m, newp, newsize);
+ set_inuse(m, p, leadsize);
+ dispose_chunk(m, p, leadsize);
+ }
+ p = newp;
+ }
+
+ /* Give back spare room at the end */
+ if (!is_mmapped(p)) {
+ size_t size = chunksize(p);
+ if (size > nb + MIN_CHUNK_SIZE) {
+ size_t remainder_size = size - nb;
+ mchunkptr remainder = chunk_plus_offset(p, nb);
+ set_inuse(m, p, nb);
+ set_inuse(m, remainder, remainder_size);
+ dispose_chunk(m, remainder, remainder_size);
+ }
+ }
+
+ mem = chunk2mem(p);
+ assert (chunksize(p) >= nb);
+ assert(((size_t)mem & (alignment - 1)) == 0);
+ check_inuse_chunk(m, p);
+ POSTACTION(m);
+ }
+ }
+ return mem;
+}
+
+/*
+ Common support for independent_X routines, handling
+ all of the combinations that can result.
+ The opts arg has:
+ bit 0 set if all elements are same size (using sizes[0])
+ bit 1 set if elements should be zeroed
+*/
+static void** ialloc(mstate m,
+ size_t n_elements,
+ size_t* sizes,
+ int opts,
+ void* chunks[]) {
+
+ size_t element_size; /* chunksize of each element, if all same */
+ size_t contents_size; /* total size of elements */
+ size_t array_size; /* request size of pointer array */
+ void* mem; /* malloced aggregate space */
+ mchunkptr p; /* corresponding chunk */
+ size_t remainder_size; /* remaining bytes while splitting */
+ void** marray; /* either "chunks" or malloced ptr array */
+ mchunkptr array_chunk; /* chunk for malloced ptr array */
+ flag_t was_enabled; /* to disable mmap */
+ size_t size;
+ size_t i;
+
+ ensure_initialization();
+ /* compute array length, if needed */
+ if (chunks != 0) {
+ if (n_elements == 0)
+ return chunks; /* nothing to do */
+ marray = chunks;
+ array_size = 0;
+ }
+ else {
+ /* if empty req, must still return chunk representing empty array */
+ if (n_elements == 0)
+ return (void**)internal_malloc(m, 0);
+ marray = 0;
+ array_size = request2size(n_elements * (sizeof(void*)));
+ }
+
+ /* compute total element size */
+ if (opts & 0x1) { /* all-same-size */
+ element_size = request2size(*sizes);
+ contents_size = n_elements * element_size;
+ }
+ else { /* add up all the sizes */
+ element_size = 0;
+ contents_size = 0;
+ for (i = 0; i != n_elements; ++i)
+ contents_size += request2size(sizes[i]);
+ }
+
+ size = contents_size + array_size;
+
+ /*
+ Allocate the aggregate chunk. First disable direct-mmapping so
+ malloc won't use it, since we would not be able to later
+ free/realloc space internal to a segregated mmap region.
+ */
+ was_enabled = use_mmap(m);
+ disable_mmap(m);
+ mem = internal_malloc(m, size - CHUNK_OVERHEAD);
+ if (was_enabled)
+ enable_mmap(m);
+ if (mem == 0)
+ return 0;
+
+ if (PREACTION(m)) return 0;
+ p = mem2chunk(mem);
+ remainder_size = chunksize(p);
+
+ assert(!is_mmapped(p));
+
+ if (opts & 0x2) { /* optionally clear the elements */
+ memset((size_t*)mem, 0, remainder_size - SIZE_T_SIZE - array_size);
+ }
+
+ /* If not provided, allocate the pointer array as final part of chunk */
+ if (marray == 0) {
+ size_t array_chunk_size;
+ array_chunk = chunk_plus_offset(p, contents_size);
+ array_chunk_size = remainder_size - contents_size;
+ marray = (void**) (chunk2mem(array_chunk));
+ set_size_and_pinuse_of_inuse_chunk(m, array_chunk, array_chunk_size);
+ remainder_size = contents_size;
+ }
+
+ /* split out elements */
+ for (i = 0; ; ++i) {
+ marray[i] = chunk2mem(p);
+ if (i != n_elements-1) {
+ if (element_size != 0)
+ size = element_size;
+ else
+ size = request2size(sizes[i]);
+ remainder_size -= size;
+ set_size_and_pinuse_of_inuse_chunk(m, p, size);
+ p = chunk_plus_offset(p, size);
+ }
+ else { /* the final element absorbs any overallocation slop */
+ set_size_and_pinuse_of_inuse_chunk(m, p, remainder_size);
+ break;
+ }
+ }
+
+#if DEBUG
+ if (marray != chunks) {
+ /* final element must have exactly exhausted chunk */
+ if (element_size != 0) {
+ assert(remainder_size == element_size);
+ }
+ else {
+ assert(remainder_size == request2size(sizes[i]));
+ }
+ check_inuse_chunk(m, mem2chunk(marray));
+ }
+ for (i = 0; i != n_elements; ++i)
+ check_inuse_chunk(m, mem2chunk(marray[i]));
+
+#endif /* DEBUG */
+
+ POSTACTION(m);
+ return marray;
+}
+
+/* Try to free all pointers in the given array.
+ Note: this could be made faster, by delaying consolidation,
+ at the price of disabling some user integrity checks, We
+ still optimize some consolidations by combining adjacent
+ chunks before freeing, which will occur often if allocated
+ with ialloc or the array is sorted.
+*/
+static size_t internal_bulk_free(mstate m, void* array[], size_t nelem) {
+ size_t unfreed = 0;
+ if (!PREACTION(m)) {
+ void** a;
+ void** fence = &(array[nelem]);
+ for (a = array; a != fence; ++a) {
+ void* mem = *a;
+ if (mem != 0) {
+ mchunkptr p = mem2chunk(mem);
+ size_t psize = chunksize(p);
+#if FOOTERS
+ if (get_mstate_for(p) != m) {
+ ++unfreed;
+ continue;
+ }
+#endif
+ check_inuse_chunk(m, p);
+ *a = 0;
+ if (RTCHECK(ok_address(m, p) && ok_inuse(p))) {
+ void ** b = a + 1; /* try to merge with next chunk */
+ mchunkptr next = next_chunk(p);
+ if (b != fence && *b == chunk2mem(next)) {
+ size_t newsize = chunksize(next) + psize;
+ set_inuse(m, p, newsize);
+ *b = chunk2mem(p);
+ }
+ else
+ dispose_chunk(m, p, psize);
+ }
+ else {
+ CORRUPTION_ERROR_ACTION(m);
+ break;
+ }
+ }
+ }
+ if (should_trim(m, m->topsize))
+ sys_trim(m, 0);
+ POSTACTION(m);
+ }
+ return unfreed;
+}
+
+/* Traversal */
+#if MALLOC_INSPECT_ALL
+static void internal_inspect_all(mstate m,
+ void(*handler)(void *start,
+ void *end,
+ size_t used_bytes,
+ void* callback_arg),
+ void* arg) {
+ if (is_initialized(m)) {
+ mchunkptr top = m->top;
+ msegmentptr s;
+ for (s = &m->seg; s != 0; s = s->next) {
+ mchunkptr q = align_as_chunk(s->base);
+ while (segment_holds(s, q) && q->head != FENCEPOST_HEAD) {
+ mchunkptr next = next_chunk(q);
+ size_t sz = chunksize(q);
+ size_t used;
+ void* start;
+ if (is_inuse(q)) {
+ used = sz - CHUNK_OVERHEAD; /* must not be mmapped */
+ start = chunk2mem(q);
+ }
+ else {
+ used = 0;
+ if (is_small(sz)) { /* offset by possible bookkeeping */
+ start = (void*)((char*)q + sizeof(struct malloc_chunk));
+ }
+ else {
+ start = (void*)((char*)q + sizeof(struct malloc_tree_chunk));
+ }
+ }
+ if (start < (void*)next) /* skip if all space is bookkeeping */
+ handler(start, next, used, arg);
+ if (q == top)
+ break;
+ q = next;
+ }
+ }
+ }
+}
+#endif /* MALLOC_INSPECT_ALL */
+
+/* ------------------ Exported realloc, memalign, etc -------------------- */
+
+#if !ONLY_MSPACES
+
+void* dlrealloc(void* oldmem, size_t bytes) {
+ void* mem = 0;
+ if (oldmem == 0) {
+ mem = dlmalloc(bytes);
+ }
+ else if (bytes >= MAX_REQUEST) {
+ MALLOC_FAILURE_ACTION;
+ }
+#ifdef REALLOC_ZERO_BYTES_FREES
+ else if (bytes == 0) {
+ dlfree(oldmem);
+ }
+#endif /* REALLOC_ZERO_BYTES_FREES */
+ else {
+ size_t nb = request2size(bytes);
+ mchunkptr oldp = mem2chunk(oldmem);
+#if ! FOOTERS
+ mstate m = gm;
+#else /* FOOTERS */
+ mstate m = get_mstate_for(oldp);
+ if (!ok_magic(m)) {
+ USAGE_ERROR_ACTION(m, oldmem);
+ return 0;
+ }
+#endif /* FOOTERS */
+ if (!PREACTION(m)) {
+ mchunkptr newp = try_realloc_chunk(m, oldp, nb, 1);
+ POSTACTION(m);
+ if (newp != 0) {
+ check_inuse_chunk(m, newp);
+ mem = chunk2mem(newp);
+ }
+ else {
+ mem = internal_malloc(m, bytes);
+ if (mem != 0) {
+ size_t oc = chunksize(oldp) - overhead_for(oldp);
+ memcpy(mem, oldmem, (oc < bytes)? oc : bytes);
+ internal_free(m, oldmem);
+ }
+ }
+ }
+ }
+ return mem;
+}
+
+void* dlrealloc_in_place(void* oldmem, size_t bytes) {
+ void* mem = 0;
+ if (oldmem != 0) {
+ if (bytes >= MAX_REQUEST) {
+ MALLOC_FAILURE_ACTION;
+ }
+ else {
+ size_t nb = request2size(bytes);
+ mchunkptr oldp = mem2chunk(oldmem);
+#if ! FOOTERS
+ mstate m = gm;
+#else /* FOOTERS */
+ mstate m = get_mstate_for(oldp);
+ if (!ok_magic(m)) {
+ USAGE_ERROR_ACTION(m, oldmem);
+ return 0;
+ }
+#endif /* FOOTERS */
+ if (!PREACTION(m)) {
+ mchunkptr newp = try_realloc_chunk(m, oldp, nb, 0);
+ POSTACTION(m);
+ if (newp == oldp) {
+ check_inuse_chunk(m, newp);
+ mem = oldmem;
+ }
+ }
+ }
+ }
+ return mem;
+}
+
+void* dlmemalign(size_t alignment, size_t bytes) {
+ if (alignment <= MALLOC_ALIGNMENT) {
+ return dlmalloc(bytes);
+ }
+ return internal_memalign(gm, alignment, bytes);
+}
+
+int dlposix_memalign(void** pp, size_t alignment, size_t bytes) {
+ void* mem = 0;
+ if (alignment == MALLOC_ALIGNMENT)
+ mem = dlmalloc(bytes);
+ else {
+ size_t d = alignment / sizeof(void*);
+ size_t r = alignment % sizeof(void*);
+ if (r != 0 || d == 0 || (d & (d-SIZE_T_ONE)) != 0)
+ return EINVAL;
+ else if (bytes <= MAX_REQUEST - alignment) {
+ if (alignment < MIN_CHUNK_SIZE)
+ alignment = MIN_CHUNK_SIZE;
+ mem = internal_memalign(gm, alignment, bytes);
+ }
+ }
+ if (mem == 0)
+ return ENOMEM;
+ else {
+ *pp = mem;
+ return 0;
+ }
+}
+
+void* dlvalloc(size_t bytes) {
+ size_t pagesz;
+ ensure_initialization();
+ pagesz = mparams.page_size;
+ return dlmemalign(pagesz, bytes);
+}
+
+void* dlpvalloc(size_t bytes) {
+ size_t pagesz;
+ ensure_initialization();
+ pagesz = mparams.page_size;
+ return dlmemalign(pagesz, (bytes + pagesz - SIZE_T_ONE) & ~(pagesz - SIZE_T_ONE));
+}
+
+void** dlindependent_calloc(size_t n_elements, size_t elem_size,
+ void* chunks[]) {
+ size_t sz = elem_size; /* serves as 1-element array */
+ return ialloc(gm, n_elements, &sz, 3, chunks);
+}
+
+void** dlindependent_comalloc(size_t n_elements, size_t sizes[],
+ void* chunks[]) {
+ return ialloc(gm, n_elements, sizes, 0, chunks);
+}
+
+size_t dlbulk_free(void* array[], size_t nelem) {
+ return internal_bulk_free(gm, array, nelem);
+}
+
+#if MALLOC_INSPECT_ALL
+void dlmalloc_inspect_all(void(*handler)(void *start,
+ void *end,
+ size_t used_bytes,
+ void* callback_arg),
+ void* arg) {
+ ensure_initialization();
+ if (!PREACTION(gm)) {
+ internal_inspect_all(gm, handler, arg);
+ POSTACTION(gm);
+ }
+}
+#endif /* MALLOC_INSPECT_ALL */
+
+int dlmalloc_trim(size_t pad) {
+ int result = 0;
+ ensure_initialization();
+ if (!PREACTION(gm)) {
+ result = sys_trim(gm, pad);
+ POSTACTION(gm);
+ }
+ return result;
+}
+
+size_t dlmalloc_footprint(void) {
+ return gm->footprint;
+}
+
+size_t dlmalloc_max_footprint(void) {
+ return gm->max_footprint;
+}
+
+size_t dlmalloc_footprint_limit(void) {
+ size_t maf = gm->footprint_limit;
+ return maf == 0 ? MAX_SIZE_T : maf;
+}
+
+size_t dlmalloc_set_footprint_limit(size_t bytes) {
+ size_t result; /* invert sense of 0 */
+ if (bytes == 0)
+ result = granularity_align(1); /* Use minimal size */
+ if (bytes == MAX_SIZE_T)
+ result = 0; /* disable */
+ else
+ result = granularity_align(bytes);
+ return gm->footprint_limit = result;
+}
+
+#if !NO_MALLINFO
+struct mallinfo dlmallinfo(void) {
+ return internal_mallinfo(gm);
+}
+#endif /* NO_MALLINFO */
+
+#if !NO_MALLOC_STATS
+void dlmalloc_stats() {
+ internal_malloc_stats(gm);
+}
+#endif /* NO_MALLOC_STATS */
+
+int dlmallopt(int param_number, int value) {
+ return change_mparam(param_number, value);
+}
+
+size_t dlmalloc_usable_size(void* mem) {
+ if (mem != 0) {
+ mchunkptr p = mem2chunk(mem);
+ if (is_inuse(p))
+ return chunksize(p) - overhead_for(p);
+ }
+ return 0;
+}
+
+#endif /* !ONLY_MSPACES */
+
+/* ----------------------------- user mspaces ---------------------------- */
+
+#if MSPACES
+
+static mstate init_user_mstate(char* tbase, size_t tsize) {
+ size_t msize = pad_request(sizeof(struct malloc_state));
+ mchunkptr mn;
+ mchunkptr msp = align_as_chunk(tbase);
+ mstate m = (mstate)(chunk2mem(msp));
+ memset(m, 0, msize);
+ (void)INITIAL_LOCK(&m->mutex);
+ msp->head = (msize|INUSE_BITS);
+ m->seg.base = m->least_addr = tbase;
+ m->seg.size = m->footprint = m->max_footprint = tsize;
+ m->magic = mparams.magic;
+ m->release_checks = MAX_RELEASE_CHECK_RATE;
+ m->mflags = mparams.default_mflags;
+ m->extp = 0;
+ m->exts = 0;
+ disable_contiguous(m);
+ init_bins(m);
+ mn = next_chunk(mem2chunk(m));
+ init_top(m, mn, (size_t)((tbase + tsize) - (char*)mn) - TOP_FOOT_SIZE);
+ check_top_chunk(m, m->top);
+ return m;
+}
+
+mspace create_mspace(size_t capacity, int locked) {
+ mstate m = 0;
+ size_t msize;
+ ensure_initialization();
+ msize = pad_request(sizeof(struct malloc_state));
+ if (capacity < (size_t) -(msize + TOP_FOOT_SIZE + mparams.page_size)) {
+ size_t rs = ((capacity == 0)? mparams.granularity :
+ (capacity + TOP_FOOT_SIZE + msize));
+ size_t tsize = granularity_align(rs);
+ char* tbase = (char*)(CALL_MMAP(tsize));
+ if (tbase != CMFAIL) {
+ m = init_user_mstate(tbase, tsize);
+ m->seg.sflags = USE_MMAP_BIT;
+ set_lock(m, locked);
+ }
+ }
+ return (mspace)m;
+}
+
+mspace create_mspace_with_base(void* base, size_t capacity, int locked) {
+ mstate m = 0;
+ size_t msize;
+ ensure_initialization();
+ msize = pad_request(sizeof(struct malloc_state));
+ if (capacity > msize + TOP_FOOT_SIZE &&
+ capacity < (size_t) -(msize + TOP_FOOT_SIZE + mparams.page_size)) {
+ m = init_user_mstate((char*)base, capacity);
+ m->seg.sflags = EXTERN_BIT;
+ set_lock(m, locked);
+ }
+ return (mspace)m;
+}
+
+int mspace_track_large_chunks(mspace msp, int enable) {
+ int ret = 0;
+ mstate ms = (mstate)msp;
+ if (!PREACTION(ms)) {
+ if (!use_mmap(ms)) {
+ ret = 1;
+ }
+ if (!enable) {
+ enable_mmap(ms);
+ } else {
+ disable_mmap(ms);
+ }
+ POSTACTION(ms);
+ }
+ return ret;
+}
+
+size_t destroy_mspace(mspace msp) {
+ size_t freed = 0;
+ mstate ms = (mstate)msp;
+ if (ok_magic(ms)) {
+ msegmentptr sp = &ms->seg;
+ (void)DESTROY_LOCK(&ms->mutex); /* destroy before unmapped */
+ while (sp != 0) {
+ char* base = sp->base;
+ size_t size = sp->size;
+ flag_t flag = sp->sflags;
+ (void)base; /* placate people compiling -Wunused-variable */
+ sp = sp->next;
+ if ((flag & USE_MMAP_BIT) && !(flag & EXTERN_BIT) &&
+ CALL_MUNMAP(base, size) == 0)
+ freed += size;
+ }
+ }
+ else {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+ return freed;
+}
+
+void mspace_get_address_and_size (mspace msp, unsigned long long *addrp,
+ unsigned long long *sizep)
+{
+ mstate ms;
+ msegment *this_seg;
+
+ ms = (mstate)msp;
+ this_seg = &ms->seg;
+
+ *addrp = (unsigned long long) this_seg->base;
+ *sizep = this_seg->size;
+}
+
+int mspace_is_heap_object (mspace msp, void *p)
+{
+ msegment *this_seg;
+ char *pp, *base;
+ mstate ms;
+
+ ms = (mstate)msp;
+
+ this_seg = &ms->seg;
+ pp = (char *) p;
+
+ while (this_seg)
+ {
+ base = this_seg->base;
+ if (pp >= base && pp < (base + this_seg->size))
+ return 1;
+ this_seg = this_seg->next;
+ }
+ return 0;
+}
+
+void *mspace_least_addr (mspace msp)
+{
+ mstate ms = (mstate) msp;
+ return (void *) ms->least_addr;
+}
+
+void mspace_disable_expand (mspace msp)
+{
+ mstate ms = (mstate)msp;
+
+ disable_expand (ms);
+}
+
+int mspace_enable_disable_trace (mspace msp, int enable)
+{
+ mstate ms = (mstate)msp;
+ int was_enabled = 0;
+
+ if (use_trace(ms) == 1)
+ was_enabled = 1;
+
+ if (enable)
+ enable_trace (ms);
+ else
+ disable_trace (ms);
+
+ return (was_enabled);
+}
+
+void* mspace_get_aligned (mspace msp,
+ unsigned long long n_user_data_bytes,
+ unsigned long long align,
+ unsigned long long align_offset) {
+ char *rv;
+ unsigned long long searchp;
+ unsigned *wwp; /* "where's Waldo" pointer */
+ mstate ms = (mstate)msp;
+
+ /*
+ * Allocate space for the "Where's Waldo?" pointer
+ * the base of the dlmalloc object
+ */
+ n_user_data_bytes += sizeof(unsigned);
+
+ /*
+ * Alignment requests less than the size of an mmx vector are ignored
+ */
+ if (align < 16) {
+ rv = mspace_malloc (msp, n_user_data_bytes);
+ if (rv == 0)
+ return rv;
+
+ if (use_trace(ms)) {
+ mchunkptr p = mem2chunk(rv);
+ size_t psize = chunksize(p);
+
+ mheap_get_trace ((u64)rv + sizeof (unsigned), psize);
+ }
+
+ wwp = (unsigned *)rv;
+ *wwp = 0;
+ rv += sizeof (unsigned);
+
+ return rv;
+ }
+
+ /*
+ * Alignment requests greater than 4K must be at offset zero,
+ * and must be freed using mspace_free_no_offset - or never freed -
+ * since the "Where's Waldo?" pointer would waste too much space.
+ *
+ * Waldo is the address of the chunk of memory returned by mspace_malloc,
+ * which we need later to call mspace_free...
+ */
+ if (align > 4<<10 || align_offset == ~0ULL) {
+ n_user_data_bytes -= sizeof(unsigned);
+ assert(align_offset == 0);
+ rv = internal_memalign(ms, (size_t)align, n_user_data_bytes);
+
+ /* Trace the allocation */
+ if (rv && use_trace(ms)) {
+ mchunkptr p = mem2chunk(rv);
+ size_t psize = chunksize(p);
+ mheap_get_trace ((u64)rv, psize);
+ }
+ return rv;
+ }
+
+ align = clib_max (align, MALLOC_ALIGNMENT);
+ align = max_pow2 (align);
+
+ /* Correct align offset to be smaller than alignment. */
+ align_offset &= (align - 1);
+
+ n_user_data_bytes += align;
+ rv = mspace_malloc (msp, n_user_data_bytes);
+
+ if (rv == 0)
+ return rv;
+
+ /* Honor the alignment request */
+ searchp = (unsigned long long)(rv + sizeof (unsigned));
+
+#if 0 /* this is the idea... */
+ while ((searchp + align_offset) % align)
+ searchp++;
+#endif
+
+ {
+ unsigned long long where_now, delta;
+
+ where_now = (searchp + align_offset) % align;
+ delta = align - where_now;
+
+ searchp += delta;
+ }
+
+ wwp = (unsigned *)(searchp - sizeof(unsigned));
+ *wwp = (searchp - (((unsigned long long) rv) + sizeof (*wwp)));
+ assert (*wwp < align);
+
+ if (use_trace(ms)) {
+ mchunkptr p = mem2chunk(rv);
+ size_t psize = chunksize(p);
+ mheap_get_trace ((u64)rv, psize);
+ }
+ return (void *) searchp;
+}
+
+void mspace_put (mspace msp, void *p_arg)
+{
+ char *object_header;
+ unsigned *wwp;
+ mstate ms = (mstate)msp;
+
+ /* Find the object header delta */
+ wwp = (unsigned *)p_arg;
+ wwp --;
+
+ /* Recover the dlmalloc object pointer */
+ object_header = (char *)wwp;
+ object_header -= *wwp;
+
+ /* Tracing (if enabled) */
+ if (use_trace(ms))
+ {
+ mchunkptr p = mem2chunk(object_header);
+ size_t psize = chunksize(p);
+
+ mheap_put_trace ((u64)p_arg, psize);
+ }
+
+ /* And free it... */
+ mspace_free (msp, object_header);
+}
+
+void mspace_put_no_offset (mspace msp, void *p_arg)
+{
+ mstate ms = (mstate)msp;
+
+ if (use_trace(ms))
+ {
+ mchunkptr p = mem2chunk(p_arg);
+ size_t psize = chunksize(p);
+
+ mheap_put_trace ((u64)p_arg, psize);
+ }
+ mspace_free (msp, p_arg);
+}
+
+size_t mspace_usable_size_with_delta (const void *p)
+{
+ size_t usable_size;
+ char *object_header;
+ unsigned *wwp;
+
+ /* Find the object header delta */
+ wwp = (unsigned *)p;
+ wwp --;
+
+ /* Recover the dlmalloc object pointer */
+ object_header = (char *)wwp;
+ object_header -= *wwp;
+
+ usable_size = mspace_usable_size (object_header);
+ /* account for the offset and the size of the offset... */
+ usable_size -= (*wwp + sizeof (*wwp));
+ return usable_size;
+}
+
+/*
+ mspace versions of routines are near-clones of the global
+ versions. This is not so nice but better than the alternatives.
+*/
+
+void* mspace_malloc(mspace msp, size_t bytes) {
+ mstate ms = (mstate)msp;
+ if (!ok_magic(ms)) {
+ USAGE_ERROR_ACTION(ms,ms);
+ return 0;
+ }
+ if (!PREACTION(ms)) {
+ void* mem;
+ size_t nb;
+ if (bytes <= MAX_SMALL_REQUEST) {
+ bindex_t idx;
+ binmap_t smallbits;
+ nb = (bytes < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(bytes);
+ idx = small_index(nb);
+ smallbits = ms->smallmap >> idx;
+
+ if ((smallbits & 0x3U) != 0) { /* Remainderless fit to a smallbin. */
+ mchunkptr b, p;
+ idx += ~smallbits & 1; /* Uses next bin if idx empty */
+ b = smallbin_at(ms, idx);
+ p = b->fd;
+ assert(chunksize(p) == small_index2size(idx));
+ unlink_first_small_chunk(ms, b, p, idx);
+ set_inuse_and_pinuse(ms, p, small_index2size(idx));
+ mem = chunk2mem(p);
+ check_malloced_chunk(ms, mem, nb);
+ goto postaction;
+ }
+
+ else if (nb > ms->dvsize) {
+ if (smallbits != 0) { /* Use chunk in next nonempty smallbin */
+ mchunkptr b, p, r;
+ size_t rsize;
+ bindex_t i;
+ binmap_t leftbits = (smallbits << idx) & left_bits(idx2bit(idx));
+ binmap_t leastbit = least_bit(leftbits);
+ compute_bit2idx(leastbit, i);
+ b = smallbin_at(ms, i);
+ p = b->fd;
+ assert(chunksize(p) == small_index2size(i));
+ unlink_first_small_chunk(ms, b, p, i);
+ rsize = small_index2size(i) - nb;
+ /* Fit here cannot be remainderless if 4byte sizes */
+ if (SIZE_T_SIZE != 4 && rsize < MIN_CHUNK_SIZE)
+ set_inuse_and_pinuse(ms, p, small_index2size(i));
+ else {
+ set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
+ r = chunk_plus_offset(p, nb);
+ set_size_and_pinuse_of_free_chunk(r, rsize);
+ replace_dv(ms, r, rsize);
+ }
+ mem = chunk2mem(p);
+ check_malloced_chunk(ms, mem, nb);
+ goto postaction;
+ }
+
+ else if (ms->treemap != 0 && (mem = tmalloc_small(ms, nb)) != 0) {
+ check_malloced_chunk(ms, mem, nb);
+ goto postaction;
+ }
+ }
+ }
+ else if (bytes >= MAX_REQUEST)
+ nb = MAX_SIZE_T; /* Too big to allocate. Force failure (in sys alloc) */
+ else {
+ nb = pad_request(bytes);
+ if (ms->treemap != 0 && (mem = tmalloc_large(ms, nb)) != 0) {
+ check_malloced_chunk(ms, mem, nb);
+ goto postaction;
+ }
+ }
+
+ if (nb <= ms->dvsize) {
+ size_t rsize = ms->dvsize - nb;
+ mchunkptr p = ms->dv;
+ if (rsize >= MIN_CHUNK_SIZE) { /* split dv */
+ mchunkptr r = ms->dv = chunk_plus_offset(p, nb);
+ ms->dvsize = rsize;
+ set_size_and_pinuse_of_free_chunk(r, rsize);
+ set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
+ }
+ else { /* exhaust dv */
+ size_t dvs = ms->dvsize;
+ ms->dvsize = 0;
+ ms->dv = 0;
+ set_inuse_and_pinuse(ms, p, dvs);
+ }
+ mem = chunk2mem(p);
+ check_malloced_chunk(ms, mem, nb);
+ goto postaction;
+ }
+
+ else if (nb < ms->topsize) { /* Split top */
+ size_t rsize = ms->topsize -= nb;
+ mchunkptr p = ms->top;
+ mchunkptr r = ms->top = chunk_plus_offset(p, nb);
+ r->head = rsize | PINUSE_BIT;
+ set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
+ mem = chunk2mem(p);
+ check_top_chunk(ms, ms->top);
+ check_malloced_chunk(ms, mem, nb);
+ goto postaction;
+ }
+
+ mem = sys_alloc(ms, nb);
+
+ postaction:
+ POSTACTION(ms);
+ return mem;
+ }
+
+ return 0;
+}
+
+void mspace_free(mspace msp, void* mem) {
+ if (mem != 0) {
+ mchunkptr p = mem2chunk(mem);
+#if FOOTERS
+ mstate fm = get_mstate_for(p);
+ (void)msp; /* placate people compiling -Wunused */
+#else /* FOOTERS */
+ mstate fm = (mstate)msp;
+#endif /* FOOTERS */
+ if (!ok_magic(fm)) {
+ USAGE_ERROR_ACTION(fm, p);
+ return;
+ }
+ if (!PREACTION(fm)) {
+ check_inuse_chunk(fm, p);
+ if (RTCHECK(ok_address(fm, p) && ok_inuse(p))) {
+ size_t psize = chunksize(p);
+ mchunkptr next = chunk_plus_offset(p, psize);
+ if (!pinuse(p)) {
+ size_t prevsize = p->prev_foot;
+ if (is_mmapped(p)) {
+ psize += prevsize + MMAP_FOOT_PAD;
+ if (CALL_MUNMAP((char*)p - prevsize, psize) == 0)
+ fm->footprint -= psize;
+ goto postaction;
+ }
+ else {
+ mchunkptr prev = chunk_minus_offset(p, prevsize);
+ psize += prevsize;
+ p = prev;
+ if (RTCHECK(ok_address(fm, prev))) { /* consolidate backward */
+ if (p != fm->dv) {
+ unlink_chunk(fm, p, prevsize);
+ }
+ else if ((next->head & INUSE_BITS) == INUSE_BITS) {
+ fm->dvsize = psize;
+ set_free_with_pinuse(p, psize, next);
+ goto postaction;
+ }
+ }
+ else
+ goto erroraction;
+ }
+ }
+
+ if (RTCHECK(ok_next(p, next) && ok_pinuse(next))) {
+ if (!cinuse(next)) { /* consolidate forward */
+ if (next == fm->top) {
+ size_t tsize = fm->topsize += psize;
+ fm->top = p;
+ p->head = tsize | PINUSE_BIT;
+ if (p == fm->dv) {
+ fm->dv = 0;
+ fm->dvsize = 0;
+ }
+ if (should_trim(fm, tsize))
+ sys_trim(fm, 0);
+ goto postaction;
+ }
+ else if (next == fm->dv) {
+ size_t dsize = fm->dvsize += psize;
+ fm->dv = p;
+ set_size_and_pinuse_of_free_chunk(p, dsize);
+ goto postaction;
+ }
+ else {
+ size_t nsize = chunksize(next);
+ psize += nsize;
+ unlink_chunk(fm, next, nsize);
+ set_size_and_pinuse_of_free_chunk(p, psize);
+ if (p == fm->dv) {
+ fm->dvsize = psize;
+ goto postaction;
+ }
+ }
+ }
+ else
+ set_free_with_pinuse(p, psize, next);
+
+ if (is_small(psize)) {
+ insert_small_chunk(fm, p, psize);
+ check_free_chunk(fm, p);
+ }
+ else {
+ tchunkptr tp = (tchunkptr)p;
+ insert_large_chunk(fm, tp, psize);
+ check_free_chunk(fm, p);
+ if (--fm->release_checks == 0)
+ release_unused_segments(fm);
+ }
+ goto postaction;
+ }
+ }
+ erroraction:
+ USAGE_ERROR_ACTION(fm, p);
+ postaction:
+ POSTACTION(fm);
+ }
+ }
+}
+
+void* mspace_calloc(mspace msp, size_t n_elements, size_t elem_size) {
+ void* mem;
+ size_t req = 0;
+ mstate ms = (mstate)msp;
+ if (!ok_magic(ms)) {
+ USAGE_ERROR_ACTION(ms,ms);
+ return 0;
+ }
+ if (n_elements != 0) {
+ req = n_elements * elem_size;
+ if (((n_elements | elem_size) & ~(size_t)0xffff) &&
+ (req / n_elements != elem_size))
+ req = MAX_SIZE_T; /* force downstream failure on overflow */
+ }
+ mem = internal_malloc(ms, req);
+ if (mem != 0 && calloc_must_clear(mem2chunk(mem)))
+ memset(mem, 0, req);
+ return mem;
+}
+
+void* mspace_realloc(mspace msp, void* oldmem, size_t bytes) {
+ void* mem = 0;
+ if (oldmem == 0) {
+ mem = mspace_malloc(msp, bytes);
+ }
+ else if (bytes >= MAX_REQUEST) {
+ MALLOC_FAILURE_ACTION;
+ }
+#ifdef REALLOC_ZERO_BYTES_FREES
+ else if (bytes == 0) {
+ mspace_free(msp, oldmem);
+ }
+#endif /* REALLOC_ZERO_BYTES_FREES */
+ else {
+ size_t nb = request2size(bytes);
+ mchunkptr oldp = mem2chunk(oldmem);
+#if ! FOOTERS
+ mstate m = (mstate)msp;
+#else /* FOOTERS */
+ mstate m = get_mstate_for(oldp);
+ if (!ok_magic(m)) {
+ USAGE_ERROR_ACTION(m, oldmem);
+ return 0;
+ }
+#endif /* FOOTERS */
+ if (!PREACTION(m)) {
+ mchunkptr newp = try_realloc_chunk(m, oldp, nb, 1);
+ POSTACTION(m);
+ if (newp != 0) {
+ check_inuse_chunk(m, newp);
+ mem = chunk2mem(newp);
+ }
+ else {
+ mem = mspace_malloc(m, bytes);
+ if (mem != 0) {
+ size_t oc = chunksize(oldp) - overhead_for(oldp);
+ memcpy(mem, oldmem, (oc < bytes)? oc : bytes);
+ mspace_free(m, oldmem);
+ }
+ }
+ }
+ }
+ return mem;
+}
+
+void* mspace_realloc_in_place(mspace msp, void* oldmem, size_t bytes) {
+ void* mem = 0;
+ if (oldmem != 0) {
+ if (bytes >= MAX_REQUEST) {
+ MALLOC_FAILURE_ACTION;
+ }
+ else {
+ size_t nb = request2size(bytes);
+ mchunkptr oldp = mem2chunk(oldmem);
+#if ! FOOTERS
+ mstate m = (mstate)msp;
+#else /* FOOTERS */
+ mstate m = get_mstate_for(oldp);
+ (void)msp; /* placate people compiling -Wunused */
+ if (!ok_magic(m)) {
+ USAGE_ERROR_ACTION(m, oldmem);
+ return 0;
+ }
+#endif /* FOOTERS */
+ if (!PREACTION(m)) {
+ mchunkptr newp = try_realloc_chunk(m, oldp, nb, 0);
+ POSTACTION(m);
+ if (newp == oldp) {
+ check_inuse_chunk(m, newp);
+ mem = oldmem;
+ }
+ }
+ }
+ }
+ return mem;
+}
+
+void* mspace_memalign(mspace msp, size_t alignment, size_t bytes) {
+ mstate ms = (mstate)msp;
+ if (!ok_magic(ms)) {
+ USAGE_ERROR_ACTION(ms,ms);
+ return 0;
+ }
+ if (alignment <= MALLOC_ALIGNMENT)
+ return mspace_malloc(msp, bytes);
+ return internal_memalign(ms, alignment, bytes);
+}
+
+void** mspace_independent_calloc(mspace msp, size_t n_elements,
+ size_t elem_size, void* chunks[]) {
+ size_t sz = elem_size; /* serves as 1-element array */
+ mstate ms = (mstate)msp;
+ if (!ok_magic(ms)) {
+ USAGE_ERROR_ACTION(ms,ms);
+ return 0;
+ }
+ return ialloc(ms, n_elements, &sz, 3, chunks);
+}
+
+void** mspace_independent_comalloc(mspace msp, size_t n_elements,
+ size_t sizes[], void* chunks[]) {
+ mstate ms = (mstate)msp;
+ if (!ok_magic(ms)) {
+ USAGE_ERROR_ACTION(ms,ms);
+ return 0;
+ }
+ return ialloc(ms, n_elements, sizes, 0, chunks);
+}
+
+size_t mspace_bulk_free(mspace msp, void* array[], size_t nelem) {
+ return internal_bulk_free((mstate)msp, array, nelem);
+}
+
+#if MALLOC_INSPECT_ALL
+void mspace_inspect_all(mspace msp,
+ void(*handler)(void *start,
+ void *end,
+ size_t used_bytes,
+ void* callback_arg),
+ void* arg) {
+ mstate ms = (mstate)msp;
+ if (ok_magic(ms)) {
+ if (!PREACTION(ms)) {
+ internal_inspect_all(ms, handler, arg);
+ POSTACTION(ms);
+ }
+ }
+ else {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+}
+#endif /* MALLOC_INSPECT_ALL */
+
+int mspace_trim(mspace msp, size_t pad) {
+ int result = 0;
+ mstate ms = (mstate)msp;
+ if (ok_magic(ms)) {
+ if (!PREACTION(ms)) {
+ result = sys_trim(ms, pad);
+ POSTACTION(ms);
+ }
+ }
+ else {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+ return result;
+}
+
+#if !NO_MALLOC_STATS
+void mspace_malloc_stats(mspace msp) {
+ mstate ms = (mstate)msp;
+ if (ok_magic(ms)) {
+ internal_malloc_stats(ms);
+ }
+ else {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+}
+#endif /* NO_MALLOC_STATS */
+
+size_t mspace_footprint(mspace msp) {
+ size_t result = 0;
+ mstate ms = (mstate)msp;
+ if (ok_magic(ms)) {
+ result = ms->footprint;
+ }
+ else {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+ return result;
+}
+
+size_t mspace_max_footprint(mspace msp) {
+ size_t result = 0;
+ mstate ms = (mstate)msp;
+ if (ok_magic(ms)) {
+ result = ms->max_footprint;
+ }
+ else {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+ return result;
+}
+
+size_t mspace_footprint_limit(mspace msp) {
+ size_t result = 0;
+ mstate ms = (mstate)msp;
+ if (ok_magic(ms)) {
+ size_t maf = ms->footprint_limit;
+ result = (maf == 0) ? MAX_SIZE_T : maf;
+ }
+ else {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+ return result;
+}
+
+size_t mspace_set_footprint_limit(mspace msp, size_t bytes) {
+ size_t result = 0;
+ mstate ms = (mstate)msp;
+ if (ok_magic(ms)) {
+ if (bytes == 0)
+ result = granularity_align(1); /* Use minimal size */
+ if (bytes == MAX_SIZE_T)
+ result = 0; /* disable */
+ else
+ result = granularity_align(bytes);
+ ms->footprint_limit = result;
+ }
+ else {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+ return result;
+}
+
+#if !NO_MALLINFO
+struct mallinfo mspace_mallinfo(mspace msp) {
+ mstate ms = (mstate)msp;
+ if (!ok_magic(ms)) {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+ return internal_mallinfo(ms);
+}
+#endif /* NO_MALLINFO */
+
+size_t mspace_usable_size(const void* mem) {
+ if (mem != 0) {
+ mchunkptr p = mem2chunk(mem);
+ if (is_inuse(p))
+ return chunksize(p) - overhead_for(p);
+ }
+ return 0;
+}
+
+int mspace_mallopt(int param_number, int value) {
+ return change_mparam(param_number, value);
+}
+
+#endif /* MSPACES */
+
+
+/* -------------------- Alternative MORECORE functions ------------------- */
+
+/*
+ Guidelines for creating a custom version of MORECORE:
+
+ * For best performance, MORECORE should allocate in multiples of pagesize.
+ * MORECORE may allocate more memory than requested. (Or even less,
+ but this will usually result in a malloc failure.)
+ * MORECORE must not allocate memory when given argument zero, but
+ instead return one past the end address of memory from previous
+ nonzero call.
+ * For best performance, consecutive calls to MORECORE with positive
+ arguments should return increasing addresses, indicating that
+ space has been contiguously extended.
+ * Even though consecutive calls to MORECORE need not return contiguous
+ addresses, it must be OK for malloc'ed chunks to span multiple
+ regions in those cases where they do happen to be contiguous.
+ * MORECORE need not handle negative arguments -- it may instead
+ just return MFAIL when given negative arguments.
+ Negative arguments are always multiples of pagesize. MORECORE
+ must not misinterpret negative args as large positive unsigned
+ args. You can suppress all such calls from even occurring by defining
+ MORECORE_CANNOT_TRIM,
+
+ As an example alternative MORECORE, here is a custom allocator
+ kindly contributed for pre-OSX macOS. It uses virtually but not
+ necessarily physically contiguous non-paged memory (locked in,
+ present and won't get swapped out). You can use it by uncommenting
+ this section, adding some #includes, and setting up the appropriate
+ defines above:
+
+ #define MORECORE osMoreCore
+
+ There is also a shutdown routine that should somehow be called for
+ cleanup upon program exit.
+
+ #define MAX_POOL_ENTRIES 100
+ #define MINIMUM_MORECORE_SIZE (64 * 1024U)
+ static int next_os_pool;
+ void *our_os_pools[MAX_POOL_ENTRIES];
+
+ void *osMoreCore(int size)
+ {
+ void *ptr = 0;
+ static void *sbrk_top = 0;
+
+ if (size > 0)
+ {
+ if (size < MINIMUM_MORECORE_SIZE)
+ size = MINIMUM_MORECORE_SIZE;
+ if (CurrentExecutionLevel() == kTaskLevel)
+ ptr = PoolAllocateResident(size + RM_PAGE_SIZE, 0);
+ if (ptr == 0)
+ {
+ return (void *) MFAIL;
+ }
+ // save ptrs so they can be freed during cleanup
+ our_os_pools[next_os_pool] = ptr;
+ next_os_pool++;
+ ptr = (void *) ((((size_t) ptr) + RM_PAGE_MASK) & ~RM_PAGE_MASK);
+ sbrk_top = (char *) ptr + size;
+ return ptr;
+ }
+ else if (size < 0)
+ {
+ // we don't currently support shrink behavior
+ return (void *) MFAIL;
+ }
+ else
+ {
+ return sbrk_top;
+ }
+ }
+
+ // cleanup any allocated memory pools
+ // called as last thing before shutting down driver
+
+ void osCleanupMem(void)
+ {
+ void **ptr;
+
+ for (ptr = our_os_pools; ptr < &our_os_pools[MAX_POOL_ENTRIES]; ptr++)
+ if (*ptr)
+ {
+ PoolDeallocate(*ptr);
+ *ptr = 0;
+ }
+ }
+
+*/
+
+
+/* -----------------------------------------------------------------------
+History:
+ v2.8.6 Wed Aug 29 06:57:58 2012 Doug Lea
+ * fix bad comparison in dlposix_memalign
+ * don't reuse adjusted asize in sys_alloc
+ * add LOCK_AT_FORK -- thanks to Kirill Artamonov for the suggestion
+ * reduce compiler warnings -- thanks to all who reported/suggested these
+
+ v2.8.5 Sun May 22 10:26:02 2011 Doug Lea (dl at gee)
+ * Always perform unlink checks unless INSECURE
+ * Add posix_memalign.
+ * Improve realloc to expand in more cases; expose realloc_in_place.
+ Thanks to Peter Buhr for the suggestion.
+ * Add footprint_limit, inspect_all, bulk_free. Thanks
+ to Barry Hayes and others for the suggestions.
+ * Internal refactorings to avoid calls while holding locks
+ * Use non-reentrant locks by default. Thanks to Roland McGrath
+ for the suggestion.
+ * Small fixes to mspace_destroy, reset_on_error.
+ * Various configuration extensions/changes. Thanks
+ to all who contributed these.
+
+ V2.8.4a Thu Apr 28 14:39:43 2011 (dl at gee.cs.oswego.edu)
+ * Update Creative Commons URL
+
+ V2.8.4 Wed May 27 09:56:23 2009 Doug Lea (dl at gee)
+ * Use zeros instead of prev foot for is_mmapped
+ * Add mspace_track_large_chunks; thanks to Jean Brouwers
+ * Fix set_inuse in internal_realloc; thanks to Jean Brouwers
+ * Fix insufficient sys_alloc padding when using 16byte alignment
+ * Fix bad error check in mspace_footprint
+ * Adaptations for ptmalloc; thanks to Wolfram Gloger.
+ * Reentrant spin locks; thanks to Earl Chew and others
+ * Win32 improvements; thanks to Niall Douglas and Earl Chew
+ * Add NO_SEGMENT_TRAVERSAL and MAX_RELEASE_CHECK_RATE options
+ * Extension hook in malloc_state
+ * Various small adjustments to reduce warnings on some compilers
+ * Various configuration extensions/changes for more platforms. Thanks
+ to all who contributed these.
+
+ V2.8.3 Thu Sep 22 11:16:32 2005 Doug Lea (dl at gee)
+ * Add max_footprint functions
+ * Ensure all appropriate literals are size_t
+ * Fix conditional compilation problem for some #define settings
+ * Avoid concatenating segments with the one provided
+ in create_mspace_with_base
+ * Rename some variables to avoid compiler shadowing warnings
+ * Use explicit lock initialization.
+ * Better handling of sbrk interference.
+ * Simplify and fix segment insertion, trimming and mspace_destroy
+ * Reinstate REALLOC_ZERO_BYTES_FREES option from 2.7.x
+ * Thanks especially to Dennis Flanagan for help on these.
+
+ V2.8.2 Sun Jun 12 16:01:10 2005 Doug Lea (dl at gee)
+ * Fix memalign brace error.
+
+ V2.8.1 Wed Jun 8 16:11:46 2005 Doug Lea (dl at gee)
+ * Fix improper #endif nesting in C++
+ * Add explicit casts needed for C++
+
+ V2.8.0 Mon May 30 14:09:02 2005 Doug Lea (dl at gee)
+ * Use trees for large bins
+ * Support mspaces
+ * Use segments to unify sbrk-based and mmap-based system allocation,
+ removing need for emulation on most platforms without sbrk.
+ * Default safety checks
+ * Optional footer checks. Thanks to William Robertson for the idea.
+ * Internal code refactoring
+ * Incorporate suggestions and platform-specific changes.
+ Thanks to Dennis Flanagan, Colin Plumb, Niall Douglas,
+ Aaron Bachmann, Emery Berger, and others.
+ * Speed up non-fastbin processing enough to remove fastbins.
+ * Remove useless cfree() to avoid conflicts with other apps.
+ * Remove internal memcpy, memset. Compilers handle builtins better.
+ * Remove some options that no one ever used and rename others.
+
+ V2.7.2 Sat Aug 17 09:07:30 2002 Doug Lea (dl at gee)
+ * Fix malloc_state bitmap array misdeclaration
+
+ V2.7.1 Thu Jul 25 10:58:03 2002 Doug Lea (dl at gee)
+ * Allow tuning of FIRST_SORTED_BIN_SIZE
+ * Use PTR_UINT as type for all ptr->int casts. Thanks to John Belmonte.
+ * Better detection and support for non-contiguousness of MORECORE.
+ Thanks to Andreas Mueller, Conal Walsh, and Wolfram Gloger
+ * Bypass most of malloc if no frees. Thanks To Emery Berger.
+ * Fix freeing of old top non-contiguous chunk im sysmalloc.
+ * Raised default trim and map thresholds to 256K.
+ * Fix mmap-related #defines. Thanks to Lubos Lunak.
+ * Fix copy macros; added LACKS_FCNTL_H. Thanks to Neal Walfield.
+ * Branch-free bin calculation
+ * Default trim and mmap thresholds now 256K.
+
+ V2.7.0 Sun Mar 11 14:14:06 2001 Doug Lea (dl at gee)
+ * Introduce independent_comalloc and independent_calloc.
+ Thanks to Michael Pachos for motivation and help.
+ * Make optional .h file available
+ * Allow > 2GB requests on 32bit systems.
+ * new WIN32 sbrk, mmap, munmap, lock code from <Walter@GeNeSys-e.de>.
+ Thanks also to Andreas Mueller <a.mueller at paradatec.de>,
+ and Anonymous.
+ * Allow override of MALLOC_ALIGNMENT (Thanks to Ruud Waij for
+ helping test this.)
+ * memalign: check alignment arg
+ * realloc: don't try to shift chunks backwards, since this
+ leads to more fragmentation in some programs and doesn't
+ seem to help in any others.
+ * Collect all cases in malloc requiring system memory into sysmalloc
+ * Use mmap as backup to sbrk
+ * Place all internal state in malloc_state
+ * Introduce fastbins (although similar to 2.5.1)
+ * Many minor tunings and cosmetic improvements
+ * Introduce USE_PUBLIC_MALLOC_WRAPPERS, USE_MALLOC_LOCK
+ * Introduce MALLOC_FAILURE_ACTION, MORECORE_CONTIGUOUS
+ Thanks to Tony E. Bennett <tbennett@nvidia.com> and others.
+ * Include errno.h to support default failure action.
+
+ V2.6.6 Sun Dec 5 07:42:19 1999 Doug Lea (dl at gee)
+ * return null for negative arguments
+ * Added Several WIN32 cleanups from Martin C. Fong <mcfong at yahoo.com>
+ * Add 'LACKS_SYS_PARAM_H' for those systems without 'sys/param.h'
+ (e.g. WIN32 platforms)
+ * Cleanup header file inclusion for WIN32 platforms
+ * Cleanup code to avoid Microsoft Visual C++ compiler complaints
+ * Add 'USE_DL_PREFIX' to quickly allow co-existence with existing
+ memory allocation routines
+ * Set 'malloc_getpagesize' for WIN32 platforms (needs more work)
+ * Use 'assert' rather than 'ASSERT' in WIN32 code to conform to
+ usage of 'assert' in non-WIN32 code
+ * Improve WIN32 'sbrk()' emulation's 'findRegion()' routine to
+ avoid infinite loop
+ * Always call 'fREe()' rather than 'free()'
+
+ V2.6.5 Wed Jun 17 15:57:31 1998 Doug Lea (dl at gee)
+ * Fixed ordering problem with boundary-stamping
+
+ V2.6.3 Sun May 19 08:17:58 1996 Doug Lea (dl at gee)
+ * Added pvalloc, as recommended by H.J. Liu
+ * Added 64bit pointer support mainly from Wolfram Gloger
+ * Added anonymously donated WIN32 sbrk emulation
+ * Malloc, calloc, getpagesize: add optimizations from Raymond Nijssen
+ * malloc_extend_top: fix mask error that caused wastage after
+ foreign sbrks
+ * Add linux mremap support code from HJ Liu
+
+ V2.6.2 Tue Dec 5 06:52:55 1995 Doug Lea (dl at gee)
+ * Integrated most documentation with the code.
+ * Add support for mmap, with help from
+ Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
+ * Use last_remainder in more cases.
+ * Pack bins using idea from colin@nyx10.cs.du.edu
+ * Use ordered bins instead of best-fit threshhold
+ * Eliminate block-local decls to simplify tracing and debugging.
+ * Support another case of realloc via move into top
+ * Fix error occuring when initial sbrk_base not word-aligned.
+ * Rely on page size for units instead of SBRK_UNIT to
+ avoid surprises about sbrk alignment conventions.
+ * Add mallinfo, mallopt. Thanks to Raymond Nijssen
+ (raymond@es.ele.tue.nl) for the suggestion.
+ * Add `pad' argument to malloc_trim and top_pad mallopt parameter.
+ * More precautions for cases where other routines call sbrk,
+ courtesy of Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
+ * Added macros etc., allowing use in linux libc from
+ H.J. Lu (hjl@gnu.ai.mit.edu)
+ * Inverted this history list
+
+ V2.6.1 Sat Dec 2 14:10:57 1995 Doug Lea (dl at gee)
+ * Re-tuned and fixed to behave more nicely with V2.6.0 changes.
+ * Removed all preallocation code since under current scheme
+ the work required to undo bad preallocations exceeds
+ the work saved in good cases for most test programs.
+ * No longer use return list or unconsolidated bins since
+ no scheme using them consistently outperforms those that don't
+ given above changes.
+ * Use best fit for very large chunks to prevent some worst-cases.
+ * Added some support for debugging
+
+ V2.6.0 Sat Nov 4 07:05:23 1995 Doug Lea (dl at gee)
+ * Removed footers when chunks are in use. Thanks to
+ Paul Wilson (wilson@cs.texas.edu) for the suggestion.
+
+ V2.5.4 Wed Nov 1 07:54:51 1995 Doug Lea (dl at gee)
+ * Added malloc_trim, with help from Wolfram Gloger
+ (wmglo@Dent.MED.Uni-Muenchen.DE).
+
+ V2.5.3 Tue Apr 26 10:16:01 1994 Doug Lea (dl at g)
+
+ V2.5.2 Tue Apr 5 16:20:40 1994 Doug Lea (dl at g)
+ * realloc: try to expand in both directions
+ * malloc: swap order of clean-bin strategy;
+ * realloc: only conditionally expand backwards
+ * Try not to scavenge used bins
+ * Use bin counts as a guide to preallocation
+ * Occasionally bin return list chunks in first scan
+ * Add a few optimizations from colin@nyx10.cs.du.edu
+
+ V2.5.1 Sat Aug 14 15:40:43 1993 Doug Lea (dl at g)
+ * faster bin computation & slightly different binning
+ * merged all consolidations to one part of malloc proper
+ (eliminating old malloc_find_space & malloc_clean_bin)
+ * Scan 2 returns chunks (not just 1)
+ * Propagate failure in realloc if malloc returns 0
+ * Add stuff to allow compilation on non-ANSI compilers
+ from kpv@research.att.com
+
+ V2.5 Sat Aug 7 07:41:59 1993 Doug Lea (dl at g.oswego.edu)
+ * removed potential for odd address access in prev_chunk
+ * removed dependency on getpagesize.h
+ * misc cosmetics and a bit more internal documentation
+ * anticosmetics: mangled names in macros to evade debugger strangeness
+ * tested on sparc, hp-700, dec-mips, rs6000
+ with gcc & native cc (hp, dec only) allowing
+ Detlefs & Zorn comparison study (in SIGPLAN Notices.)
+
+ Trial version Fri Aug 28 13:14:29 1992 Doug Lea (dl at g.oswego.edu)
+ * Based loosely on libg++-1.2X malloc. (It retains some of the overall
+ structure of old version, but most details differ.)
+
+*/