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Diffstat (limited to 'src/vppinfra/format.c')
| -rw-r--r-- | src/vppinfra/format.c | 814 |
1 files changed, 814 insertions, 0 deletions
diff --git a/src/vppinfra/format.c b/src/vppinfra/format.c new file mode 100644 index 00000000000..78e52e9a2ad --- /dev/null +++ b/src/vppinfra/format.c @@ -0,0 +1,814 @@ +/* + * Copyright (c) 2015 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +/*------------------------------------------------------------------ + * format.c -- see notice below + * + * October 2003, Eliot Dresselhaus + * + * Modifications to this file Copyright (c) 2003 by cisco Systems, Inc. + * All rights reserved. + *------------------------------------------------------------------ + */ + +/* + Copyright (c) 2001, 2002, 2003, 2006 Eliot Dresselhaus + + Permission is hereby granted, free of charge, to any person obtaining + a copy of this software and associated documentation files (the + "Software"), to deal in the Software without restriction, including + without limitation the rights to use, copy, modify, merge, publish, + distribute, sublicense, and/or sell copies of the Software, and to + permit persons to whom the Software is furnished to do so, subject to + the following conditions: + + The above copyright notice and this permission notice shall be + included in all copies or substantial portions of the Software. + + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE + LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION + OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION + WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +*/ + +#include <stdarg.h> /* va_start, etc */ + +#ifdef CLIB_UNIX +#include <unistd.h> +#include <stdio.h> +#endif + +#ifdef CLIB_STANDALONE +#include <vppinfra/standalone_stdio.h> +#endif + +#include <vppinfra/mem.h> +#include <vppinfra/format.h> +#include <vppinfra/vec.h> +#include <vppinfra/error.h> +#include <vppinfra/string.h> +#include <vppinfra/os.h> /* os_puts */ + +typedef struct +{ + /* Output number in this base. */ + u8 base; + + /* Number of show of 64 bit number. */ + u8 n_bits; + + /* Signed or unsigned. */ + u8 is_signed; + + /* Output digits uppercase (not lowercase) %X versus %x. */ + u8 uppercase_digits; +} format_integer_options_t; + +static u8 *format_integer (u8 * s, u64 number, + format_integer_options_t * options); +static u8 *format_float (u8 * s, f64 x, uword n_digits_to_print, + uword output_style); + +typedef struct +{ + /* String justification: + => right, - => left, = => center. */ + uword justify; + + /* Width of string (before and after decimal point for numbers). + 0 => natural width. */ + uword width[2]; + + /* Long => 'l', long long 'L', int 0. */ + uword how_long; + + /* Pad character. Defaults to space. */ + uword pad_char; +} format_info_t; + +static u8 * +justify (u8 * s, format_info_t * fi, uword s_len_orig) +{ + uword i0, l0, l1; + + i0 = s_len_orig; + l0 = i0 + fi->width[0]; + l1 = vec_len (s); + + /* If width is zero user returned width. */ + if (l0 == i0) + l0 = l1; + + if (l1 > l0) + _vec_len (s) = l0; + else if (l0 > l1) + { + uword n = l0 - l1; + uword n_left = 0, n_right = 0; + + switch (fi->justify) + { + case '-': + n_right = n; + break; + + case '+': + n_left = n; + break; + + case '=': + n_right = n_left = n / 2; + if (n % 2) + n_left++; + break; + } + if (n_left > 0) + { + vec_insert (s, n_left, i0); + memset (s + i0, fi->pad_char, n_left); + l1 = vec_len (s); + } + if (n_right > 0) + { + vec_resize (s, n_right); + memset (s + l1, fi->pad_char, n_right); + } + } + return s; +} + +static u8 * +do_percent (u8 ** _s, u8 * fmt, va_list * va) +{ + u8 *s = *_s; + uword c; + + u8 *f = fmt; + + format_info_t fi = { + .justify = '+', + .width = {0}, + .pad_char = ' ', + .how_long = 0, + }; + + uword i; + + ASSERT (f[0] == '%'); + + switch (c = *++f) + { + case '%': + /* %% => % */ + vec_add1 (s, c); + f++; + goto done; + + case '-': + case '+': + case '=': + fi.justify = c; + c = *++f; + break; + } + + /* Parse width0 . width1. */ + { + uword is_first_digit = 1; + + fi.width[0] = fi.width[1] = 0; + for (i = 0; i < 2; i++) + { + if (c == '0' && i == 0 && is_first_digit) + fi.pad_char = '0'; + is_first_digit = 0; + if (c == '*') + { + fi.width[i] = va_arg (*va, int); + c = *++f; + } + else + { + while (c >= '0' && c <= '9') + { + fi.width[i] = 10 * fi.width[i] + (c - '0'); + c = *++f; + } + } + if (c != '.') + break; + c = *++f; + } + } + + /* Parse %l* and %L* */ + switch (c) + { + case 'w': + /* word format. */ + fi.how_long = 'w'; + c = *++f; + break; + + case 'L': + case 'l': + fi.how_long = c; + c = *++f; + if (c == 'l' && *f == 'l') + { + fi.how_long = 'L'; + c = *++f; + } + break; + } + + /* Finally we are ready for format letter. */ + if (c != 0) + { + uword s_initial_len = vec_len (s); + format_integer_options_t o = { + .is_signed = 0, + .base = 10, + .n_bits = BITS (uword), + .uppercase_digits = 0, + }; + + f++; + + switch (c) + { + default: + { + /* Try to give a helpful error message. */ + vec_free (s); + s = format (s, "**** CLIB unknown format `%%%c' ****", c); + goto done; + } + + case 'c': + vec_add1 (s, va_arg (*va, int)); + break; + + case 'p': + vec_add1 (s, '0'); + vec_add1 (s, 'x'); + + o.is_signed = 0; + o.n_bits = BITS (uword *); + o.base = 16; + o.uppercase_digits = 0; + + s = format_integer (s, pointer_to_uword (va_arg (*va, void *)), &o); + break; + + case 'x': + case 'X': + case 'u': + case 'd': + { + u64 number; + + o.base = 10; + if (c == 'x' || c == 'X') + o.base = 16; + o.is_signed = c == 'd'; + o.uppercase_digits = c == 'X'; + + switch (fi.how_long) + { + case 'L': + number = va_arg (*va, unsigned long long); + o.n_bits = BITS (unsigned long long); + break; + + case 'l': + number = va_arg (*va, long); + o.n_bits = BITS (long); + break; + + case 'w': + number = va_arg (*va, word); + o.n_bits = BITS (uword); + break; + + default: + number = va_arg (*va, int); + o.n_bits = BITS (int); + break; + } + + s = format_integer (s, number, &o); + } + break; + + case 's': + case 'S': + { + char *cstring = va_arg (*va, char *); + uword len; + + if (!cstring) + { + cstring = "(nil)"; + len = 5; + } + else if (fi.width[1] != 0) + len = clib_min (strlen (cstring), fi.width[1]); + else + len = strlen (cstring); + + /* %S => format string as C identifier (replace _ with space). */ + if (c == 'S') + { + for (i = 0; i < len; i++) + vec_add1 (s, cstring[i] == '_' ? ' ' : cstring[i]); + } + else + vec_add (s, cstring, len); + } + break; + + case 'v': + { + u8 *v = va_arg (*va, u8 *); + uword len; + + if (fi.width[1] != 0) + len = clib_min (vec_len (v), fi.width[1]); + else + len = vec_len (v); + + vec_add (s, v, len); + } + break; + + case 'f': + case 'g': + case 'e': + /* Floating point. */ + ASSERT (fi.how_long == 0 || fi.how_long == 'l'); + s = format_float (s, va_arg (*va, double), fi.width[1], c); + break; + + case 'U': + /* User defined function. */ + { + typedef u8 *(user_func_t) (u8 * s, va_list * args); + user_func_t *u = va_arg (*va, user_func_t *); + + s = (*u) (s, va); + } + break; + } + + s = justify (s, &fi, s_initial_len); + } + +done: + *_s = s; + return f; +} + +u8 * +va_format (u8 * s, const char *fmt, va_list * va) +{ + u8 *f = (u8 *) fmt, *g; + u8 c; + + g = f; + while (1) + { + c = *f; + + if (!c) + break; + + if (c == '%') + { + if (f > g) + vec_add (s, g, f - g); + f = g = do_percent (&s, f, va); + } + else + { + f++; + } + } + + if (f > g) + vec_add (s, g, f - g); + + return s; +} + +u8 * +format (u8 * s, const char *fmt, ...) +{ + va_list va; + va_start (va, fmt); + s = va_format (s, fmt, &va); + va_end (va); + return s; +} + +word +va_fformat (FILE * f, char *fmt, va_list * va) +{ + word ret; + u8 *s; + + s = va_format (0, fmt, va); + +#ifdef CLIB_UNIX + if (f) + { + ret = fwrite (s, vec_len (s), 1, f); + } + else +#endif /* CLIB_UNIX */ + { + ret = 0; + os_puts (s, vec_len (s), /* is_error */ 0); + } + + vec_free (s); + return ret; +} + +word +fformat (FILE * f, char *fmt, ...) +{ + va_list va; + word ret; + + va_start (va, fmt); + ret = va_fformat (f, fmt, &va); + va_end (va); + + return (ret); +} + +#ifdef CLIB_UNIX +word +fdformat (int fd, char *fmt, ...) +{ + word ret; + u8 *s; + va_list va; + + va_start (va, fmt); + s = va_format (0, fmt, &va); + va_end (va); + + ret = write (fd, s, vec_len (s)); + vec_free (s); + return ret; +} +#endif + +/* Format integral type. */ +static u8 * +format_integer (u8 * s, u64 number, format_integer_options_t * options) +{ + u64 q; + u32 r; + u8 digit_buffer[128]; + u8 *d = digit_buffer + sizeof (digit_buffer); + word c, base; + + if (options->is_signed && (i64) number < 0) + { + number = -number; + vec_add1 (s, '-'); + } + + if (options->n_bits < BITS (number)) + number &= ((u64) 1 << options->n_bits) - 1; + + base = options->base; + + while (1) + { + q = number / base; + r = number % base; + + if (r < 10 + 26 + 26) + { + if (r < 10) + c = '0' + r; + else if (r < 10 + 26) + c = 'a' + (r - 10); + else + c = 'A' + (r - 10 - 26); + + if (options->uppercase_digits + && base <= 10 + 26 && c >= 'a' && c <= 'z') + c += 'A' - 'a'; + + *--d = c; + } + else /* will never happen, warning be gone */ + { + *--d = '?'; + } + + if (q == 0) + break; + + number = q; + } + + vec_add (s, d, digit_buffer + sizeof (digit_buffer) - d); + return s; +} + +/* Floating point formatting. */ +/* Deconstruct IEEE 64 bit number into sign exponent and fraction. */ +#define f64_down(f,sign,expon,fraction) \ +do { \ + union { u64 u; f64 f; } _f64_down_tmp; \ + _f64_down_tmp.f = (f); \ + (sign) = (_f64_down_tmp.u >> 63); \ + (expon) = ((_f64_down_tmp.u >> 52) & 0x7ff) - 1023; \ + (fraction) = ((_f64_down_tmp.u << 12) >> 12) | ((u64) 1 << 52); \ +} while (0) + +/* Construct IEEE 64 bit number. */ +static f64 +f64_up (uword sign, word expon, u64 fraction) +{ + union + { + u64 u; + f64 f; + } tmp; + + tmp.u = (u64) ((sign) != 0) << 63; + + expon += 1023; + if (expon > 1023) + expon = 1023; + if (expon < 0) + expon = 0; + tmp.u |= (u64) expon << 52; + + tmp.u |= fraction & (((u64) 1 << 52) - 1); + + return tmp.f; +} + +/* Returns approximate precision of number given its exponent. */ +static f64 +f64_precision (int base2_expon) +{ + static int n_bits = 0; + + if (!n_bits) + { + /* Compute number of significant bits in floating point representation. */ + f64 one = 0; + f64 small = 1; + + while (one != 1) + { + small *= .5; + n_bits++; + one = 1 + small; + } + } + + return f64_up (0, base2_expon - n_bits, 0); +} + +/* Return x 10^n */ +static f64 +times_power_of_ten (f64 x, int n) +{ + if (n >= 0) + { + static f64 t[8] = { 1e+0, 1e+1, 1e+2, 1e+3, 1e+4, 1e+5, 1e+6, 1e+7, }; + while (n >= 8) + { + x *= 1e+8; + n -= 8; + } + return x * t[n]; + } + else + { + static f64 t[8] = { 1e-0, 1e-1, 1e-2, 1e-3, 1e-4, 1e-5, 1e-6, 1e-7, }; + while (n <= -8) + { + x *= 1e-8; + n += 8; + } + return x * t[-n]; + } + +} + +/* Write x = y * 10^expon with 1 < y < 10. */ +static f64 +normalize (f64 x, word * expon_return, f64 * prec_return) +{ + word expon2, expon10; + CLIB_UNUSED (u64 fraction); + CLIB_UNUSED (word sign); + f64 prec; + + f64_down (x, sign, expon2, fraction); + + expon10 = + .5 + + expon2 * .301029995663981195213738894724493 /* Log (2) / Log (10) */ ; + + prec = f64_precision (expon2); + x = times_power_of_ten (x, -expon10); + prec = times_power_of_ten (prec, -expon10); + + while (x < 1) + { + x *= 10; + prec *= 10; + expon10--; + } + + while (x > 10) + { + x *= .1; + prec *= .1; + expon10++; + } + + if (x + prec >= 10) + { + x = 1; + expon10++; + } + + *expon_return = expon10; + *prec_return = prec; + + return x; +} + +static u8 * +add_some_zeros (u8 * s, uword n_zeros) +{ + while (n_zeros > 0) + { + vec_add1 (s, '0'); + n_zeros--; + } + return s; +} + +/* Format a floating point number with the given number of fractional + digits (e.g. 1.2345 with 2 fraction digits yields "1.23") and output style. */ +static u8 * +format_float (u8 * s, f64 x, uword n_fraction_digits, uword output_style) +{ + f64 prec; + word sign, expon, n_fraction_done, added_decimal_point; + /* Position of decimal point relative to where we are. */ + word decimal_point; + + /* Default number of digits to print when its not specified. */ + if (n_fraction_digits == ~0) + n_fraction_digits = 7; + n_fraction_done = 0; + decimal_point = 0; + added_decimal_point = 0; + sign = expon = 0; + + /* Special case: zero. */ + if (x == 0) + { + do_zero: + vec_add1 (s, '0'); + goto done; + } + + if (x < 0) + { + x = -x; + sign = 1; + } + + /* Check for infinity. */ + if (x == x / 2) + return format (s, "%cinfinity", sign ? '-' : '+'); + + x = normalize (x, &expon, &prec); + + /* Not enough digits to print anything: so just print 0 */ + if ((word) - expon > (word) n_fraction_digits + && (output_style == 'f' || (output_style == 'g'))) + goto do_zero; + + if (sign) + vec_add1 (s, '-'); + + if (output_style == 'f' + || (output_style == 'g' && expon > -10 && expon < 10)) + { + if (expon < 0) + { + /* Add decimal point and leading zeros. */ + vec_add1 (s, '.'); + n_fraction_done = clib_min (-(expon + 1), n_fraction_digits); + s = add_some_zeros (s, n_fraction_done); + decimal_point = -n_fraction_done; + added_decimal_point = 1; + } + else + decimal_point = expon + 1; + } + else + { + /* Exponential output style. */ + decimal_point = 1; + output_style = 'e'; + } + + while (1) + { + uword digit; + + /* Number is smaller than precision: call it zero. */ + if (x < prec) + break; + + digit = x; + x -= digit; + if (x + prec >= 1) + { + digit++; + x -= 1; + } + + /* Round last printed digit. */ + if (decimal_point <= 0 + && n_fraction_done + 1 == n_fraction_digits && digit < 9) + digit += x >= .5; + + vec_add1 (s, '0' + digit); + + /* Move rightwards towards/away from decimal point. */ + decimal_point--; + + n_fraction_done += decimal_point < 0; + if (decimal_point <= 0 && n_fraction_done >= n_fraction_digits) + break; + + if (decimal_point == 0 && x != 0) + { + vec_add1 (s, '.'); + added_decimal_point = 1; + } + + x *= 10; + prec *= 10; + } + +done: + if (decimal_point > 0) + { + s = add_some_zeros (s, decimal_point); + decimal_point = 0; + } + + if (n_fraction_done < n_fraction_digits) + { + if (!added_decimal_point) + vec_add1 (s, '.'); + s = add_some_zeros (s, n_fraction_digits - n_fraction_done); + } + + if (output_style == 'e') + s = format (s, "e%wd", expon); + + return s; +} + + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |