lib/compat.c

   1 /*
   2  * Reimplementations of standard functions for platforms that don't have them.
   3  *
   4  * Copyright (C) 1998 Andrew Tridgell
   5  * Copyright (C) 2002 Martin Pool
   6  * Copyright (C) 2004-2020 Wayne Davison
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 3 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; if not, visit the http://fsf.org website.
  20  */
  21
  22 #include "rsync.h"
  23 #include "itypes.h"
  24
  25 static char number_separator;
  26
  27 char get_number_separator(void)
  28 {
  29         if (!number_separator) {
  30                 char buf[32];
  31                 snprintf(buf, sizeof buf, "%f", 3.14);
  32                 if (strchr(buf, '.') != NULL)
  33                         number_separator = ',';
  34                 else
  35                         number_separator = '.';
  36         }
  37
  38         return number_separator;
  39 }
  40
  41 char get_decimal_point(void)
  42 {
  43         return get_number_separator() == ',' ? '.' : ',';
  44 }
  45
  46 #ifndef HAVE_GETCWD
  47  char *getcwd(char *buf, int size)
  48 {
  49         return getwd(buf);
  50 }
  51 #endif
  52
  53
  54 #ifndef HAVE_WAITPID
  55  pid_t waitpid(pid_t pid, int *statptr, int options)
  56 {
  57 #ifdef HAVE_WAIT4
  58         return wait4(pid, statptr, options, NULL);
  59 #else
  60         /* If wait4 is also not available, try wait3 for SVR3 variants */
  61         /* Less ideal because can't actually request a specific pid */
  62         /* At least the WNOHANG option is supported */
  63         /* Code borrowed from apache fragment written by dwd@bell-labs.com */
  64         int tmp_pid, dummystat;;
  65         if (kill(pid, 0) == -1) {
  66                 errno = ECHILD;
  67                 return -1;
  68         }
  69         if (statptr == NULL)
  70                 statptr = &dummystat;
  71         while (((tmp_pid = wait3(statptr, options, 0)) != pid) &&
  72                     (tmp_pid != -1) && (tmp_pid != 0) && (pid != -1))
  73             ;
  74         return tmp_pid;
  75 #endif
  76 }
  77 #endif
  78
  79
  80 #ifndef HAVE_MEMMOVE
  81  void *memmove(void *dest, const void *src, size_t n)
  82 {
  83         bcopy((char *) src, (char *) dest, n);
  84         return dest;
  85 }
  86 #endif
  87
  88 #ifndef HAVE_STRPBRK
  89 /**
  90  * Find the first occurrence in @p s of any character in @p accept.
  91  *
  92  * Derived from glibc
  93  **/
  94  char *strpbrk(const char *s, const char *accept)
  95 {
  96         while (*s != '\0')  {
  97                 const char *a = accept;
  98                 while (*a != '\0') {
  99                         if (*a++ == *s) return (char *)s;
 100                 }
 101                 ++s;
 102         }
 103
 104         return NULL;
 105 }
 106 #endif
 107
 108
 109 #ifndef HAVE_STRLCPY
 110 /**
 111  * Like strncpy but does not 0 fill the buffer and always null
 112  * terminates.
 113  *
 114  * @param bufsize is the size of the destination buffer.
 115  *
 116  * @return index of the terminating byte.
 117  **/
 118  size_t strlcpy(char *d, const char *s, size_t bufsize)
 119 {
 120         size_t len = strlen(s);
 121         size_t ret = len;
 122         if (bufsize > 0) {
 123                 if (len >= bufsize)
 124                         len = bufsize-1;
 125                 memcpy(d, s, len);
 126                 d[len] = 0;
 127         }
 128         return ret;
 129 }
 130 #endif
 131
 132 #ifndef HAVE_STRLCAT
 133 /**
 134  * Like strncat() but does not 0 fill the buffer and always null
 135  * terminates.
 136  *
 137  * @param bufsize length of the buffer, which should be one more than
 138  * the maximum resulting string length.
 139  **/
 140  size_t strlcat(char *d, const char *s, size_t bufsize)
 141 {
 142         size_t len1 = strlen(d);
 143         size_t len2 = strlen(s);
 144         size_t ret = len1 + len2;
 145
 146         if (len1 < bufsize - 1) {
 147                 if (len2 >= bufsize - len1)
 148                         len2 = bufsize - len1 - 1;
 149                 memcpy(d+len1, s, len2);
 150                 d[len1+len2] = 0;
 151         }
 152         return ret;
 153 }
 154 #endif
 155
 156 /* some systems don't take the 2nd argument */
 157 int sys_gettimeofday(struct timeval *tv)
 158 {
 159 #ifdef HAVE_GETTIMEOFDAY_TZ
 160         return gettimeofday(tv, NULL);
 161 #else
 162         return gettimeofday(tv);
 163 #endif
 164 }
 165
 166 /* Return the int64 number as a string.  If the human_flag arg is non-zero,
 167  * we may output the number in K, M, G, or T units.  If we don't add a unit
 168  * suffix, we will append the fract string, if it is non-NULL.  We can
 169  * return up to 4 buffers at a time. */
 170 char *do_big_num(int64 num, int human_flag, const char *fract)
 171 {
 172         static char bufs[4][128]; /* more than enough room */
 173         static unsigned int n;
 174         char *s;
 175         int len, negated;
 176
 177         if (human_flag && !number_separator)
 178                 (void)get_number_separator();
 179
 180         n = (n + 1) % (sizeof bufs / sizeof bufs[0]);
 181
 182         if (human_flag > 1) {
 183                 int mult = human_flag == 2 ? 1000 : 1024;
 184                 if (num >= mult || num <= -mult) {
 185                         double dnum = (double)num / mult;
 186                         char units;
 187                         if (num < 0)
 188                                 dnum = -dnum;
 189                         if (dnum < mult)
 190                                 units = 'K';
 191                         else if ((dnum /= mult) < mult)
 192                                 units = 'M';
 193                         else if ((dnum /= mult) < mult)
 194                                 units = 'G';
 195                         else if ((dnum /= mult) < mult)
 196                                 units = 'T';
 197                         else {
 198                                 dnum /= mult;
 199                                 units = 'P';
 200                         }
 201                         if (num < 0)
 202                                 dnum = -dnum;
 203                         snprintf(bufs[n], sizeof bufs[0], "%.2f%c", dnum, units);
 204                         return bufs[n];
 205                 }
 206         }
 207
 208         s = bufs[n] + sizeof bufs[0] - 1;
 209         if (fract) {
 210                 len = strlen(fract);
 211                 s -= len;
 212                 strlcpy(s, fract, len + 1);
 213         } else
 214                 *s = '\0';
 215
 216         len = 0;
 217
 218         if (!num)
 219                 *--s = '0';
 220         if (num < 0) {
 221                 /* A maximum-size negated number can't fit as a positive,
 222                  * so do one digit in negated form to start us off. */
 223                 *--s = (char)(-(num % 10)) + '0';
 224                 num = -(num / 10);
 225                 len++;
 226                 negated = 1;
 227         } else
 228                 negated = 0;
 229
 230         while (num) {
 231                 if (human_flag) {
 232                         if (len == 3) {
 233                                 *--s = number_separator;
 234                                 len = 1;
 235                         } else
 236                                 len++;
 237                 }
 238                 *--s = (char)(num % 10) + '0';
 239                 num /= 10;
 240         }
 241
 242         if (negated)
 243                 *--s = '-';
 244
 245         return s;
 246 }
 247
 248 /* Return the double number as a string.  If the human_flag option is > 1,
 249  * we may output the number in K, M, G, or T units.  The buffer we use for
 250  * our result is either a single static buffer defined here, or a buffer
 251  * we get from do_big_num(). */
 252 char *do_big_dnum(double dnum, int human_flag, int decimal_digits)
 253 {
 254         static char tmp_buf[128];
 255 #if SIZEOF_INT64 >= 8
 256         char *fract;
 257
 258         snprintf(tmp_buf, sizeof tmp_buf, "%.*f", decimal_digits, dnum);
 259
 260         if (!human_flag || (dnum < 1000.0 && dnum > -1000.0))
 261                 return tmp_buf;
 262
 263         for (fract = tmp_buf+1; isDigit(fract); fract++) {}
 264
 265         return do_big_num((int64)dnum, human_flag, fract);
 266 #else
 267         /* A big number might lose digits converting to a too-short int64,
 268          * so let's just return the raw double conversion. */
 269         snprintf(tmp_buf, sizeof tmp_buf, "%.*f", decimal_digits, dnum);
 270         return tmp_buf;
 271 #endif
 272 }