Line data    Source code

       1             : /*
       2             :  * lwan - web server
       3             :  * Copyright (c) 2012 L. A. F. Pereira <l@tia.mat.br>
       4             :  *
       5             :  * This program is free software; you can redistribute it and/or
       6             :  * modify it under the terms of the GNU General Public License
       7             :  * as published by the Free Software Foundation; either version 2
       8             :  * of the License, or any later version.
       9             :  *
      10             :  * This program is distributed in the hope that it will be useful,
      11             :  * but WITHOUT ANY WARRANTY; without even the implied warranty of
      12             :  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      13             :  * GNU General Public License for more details.
      14             :  *
      15             :  * You should have received a copy of the GNU General Public License
      16             :  * along with this program; if not, write to the Free Software
      17             :  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
      18             :  * USA.
      19             :  */
      20             : 
      21             : #include <assert.h>
      22             : 
      23             : #include "lwan-private.h"
      24             : 
      25             : #include "int-to-str.h"
      26             : 
      27             : static const char digits[201] = "0001020304050607080910111213141516171819"
      28             :                                 "2021222324252627282930313233343536373839"
      29             :                                 "4041424344454647484950515253545556575859"
      30             :                                 "6061626364656667686970717273747576777879"
      31             :                                 "8081828384858687888990919293949596979899";
      32             : 
      33             : ALWAYS_INLINE __attribute__((pure)) const char *
      34        2460 : uint_to_string_2_digits(size_t value)
      35             : {
      36        2460 :     assert(value <= 99);
      37        2460 :     return &digits[2 * value];
      38             : }
      39             : 
      40         506 : ALWAYS_INLINE char *uint_to_string(size_t value,
      41             :                                    char dst[static INT_TO_STR_BUFFER_SIZE],
      42             :                                    size_t *length_out)
      43             : {
      44             :     /*
      45             :      * Based on routine by A. Alexandrescu, licensed under CC0
      46             :      * https://creativecommons.org/publicdomain/zero/1.0/legalcode
      47             :      */
      48             :     static const size_t length = INT_TO_STR_BUFFER_SIZE;
      49        2757 :     size_t next = length - 1;
      50        2757 :     dst[next--] = '\0';
      51        5069 :     while (value >= 100) {
      52        2312 :         const uint32_t i = (uint32_t)((value % 100) * 2);
      53        2312 :         value /= 100;
      54        2312 :         dst[next] = digits[i + 1];
      55        2312 :         dst[next - 1] = digits[i];
      56        2312 :         next -= 2;
      57             :     }
      58             :     // Handle last 1-2 digits
      59        2757 :     if (value < 10) {
      60         297 :         dst[next] = (char)('0' + (uint32_t)value);
      61         297 :         *length_out = length - next - 1;
      62         297 :         return dst + next;
      63             :     }
      64        2460 :     uint32_t i = (uint32_t)value * 2;
      65        2460 :     dst[next] = digits[i + 1];
      66        2460 :     dst[next - 1] = digits[i];
      67        2460 :     *length_out = length - next;
      68        2460 :     return dst + next - 1;
      69             : }
      70             : 
      71        2251 : ALWAYS_INLINE char *int_to_string(ssize_t value,
      72             :                                   char dst[static INT_TO_STR_BUFFER_SIZE],
      73             :                                   size_t *length_out)
      74             : {
      75        2251 :     if (value < 0) {
      76           0 :         char *p = uint_to_string((size_t)-value, dst, length_out);
      77           0 :         *--p = '-';
      78           0 :         ++*length_out;
      79             : 
      80           0 :         return p;
      81             :     }
      82             : 
      83        4502 :     return uint_to_string((size_t)value, dst, length_out);
      84             : }