1 files changed, 87 insertions, 0 deletions
diff --git a/nginx/src/os/unix/ngx_errno.c b/nginx/src/os/unix/ngx_errno.c
new file mode 100644
index 0000000..e787b23
--- /dev/null
+++ b/nginx/src/os/unix/ngx_errno.c
@@ -0,0 +1,87 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ * Copyright (C) Nginx, Inc.
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+
+
+/*
+ * The strerror() messages are copied because:
+ *
+ * 1) strerror() and strerror_r() functions are not Async-Signal-Safe,
+ *    therefore, they cannot be used in signal handlers;
+ *
+ * 2) a direct sys_errlist[] array may be used instead of these functions,
+ *    but Linux linker warns about its usage:
+ *
+ * warning: `sys_errlist' is deprecated; use `strerror' or `strerror_r' instead
+ * warning: `sys_nerr' is deprecated; use `strerror' or `strerror_r' instead
+ *
+ *    causing false bug reports.
+ */
+
+
+static ngx_str_t  *ngx_sys_errlist;
+static ngx_str_t   ngx_unknown_error = ngx_string("Unknown error");
+
+
+u_char *
+ngx_strerror(ngx_err_t err, u_char *errstr, size_t size)
+{
+    ngx_str_t  *msg;
+
+    msg = ((ngx_uint_t) err < NGX_SYS_NERR) ? &ngx_sys_errlist[err]:
+                                              &ngx_unknown_error;
+    size = ngx_min(size, msg->len);
+
+    return ngx_cpymem(errstr, msg->data, size);
+}
+
+
+ngx_int_t
+ngx_strerror_init(void)
+{
+    char       *msg;
+    u_char     *p;
+    size_t      len;
+    ngx_err_t   err;
+
+    /*
+     * ngx_strerror() is not ready to work at this stage, therefore,
+     * malloc() is used and possible errors are logged using strerror().
+     */
+
+    len = NGX_SYS_NERR * sizeof(ngx_str_t);
+
+    ngx_sys_errlist = malloc(len);
+    if (ngx_sys_errlist == NULL) {
+        goto failed;
+    }
+
+    for (err = 0; err < NGX_SYS_NERR; err++) {
+        msg = strerror(err);
+        len = ngx_strlen(msg);
+
+        p = malloc(len);
+        if (p == NULL) {
+            goto failed;
+        }
+
+        ngx_memcpy(p, msg, len);
+        ngx_sys_errlist[err].len = len;
+        ngx_sys_errlist[err].data = p;
+    }
+
+    return NGX_OK;
+
+failed:
+
+    err = errno;
+    ngx_log_stderr(0, "malloc(%uz) failed (%d: %s)", len, err, strerror(err));
+
+    return NGX_ERROR;
+}