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 #ifndef HAVE_STRDUP
  28  char *strdup(char *s)
  29 {
  30         int len = strlen(s) + 1;
  31         char *ret = (char *)malloc(len);
  32         if (ret)
  33                 memcpy(ret, s, len);
  34         return ret;
  35 }
  36 #endif
  37
  38 #ifndef HAVE_GETCWD
  39  char *getcwd(char *buf, int size)
  40 {
  41         return getwd(buf);
  42 }
  43 #endif
  44
  45
  46 #ifndef HAVE_WAITPID
  47  pid_t waitpid(pid_t pid, int *statptr, int options)
  48 {
  49 #ifdef HAVE_WAIT4
  50         return wait4(pid, statptr, options, NULL);
  51 #else
  52         /* If wait4 is also not available, try wait3 for SVR3 variants */
  53         /* Less ideal because can't actually request a specific pid */
  54         /* At least the WNOHANG option is supported */
  55         /* Code borrowed from apache fragment written by dwd@bell-labs.com */
  56         int tmp_pid, dummystat;;
  57         if (kill(pid, 0) == -1) {
  58                 errno = ECHILD;
  59                 return -1;
  60         }
  61         if (statptr == NULL)
  62                 statptr = &dummystat;
  63         while (((tmp_pid = wait3(statptr, options, 0)) != pid) &&
  64                     (tmp_pid != -1) && (tmp_pid != 0) && (pid != -1))
  65             ;
  66         return tmp_pid;
  67 #endif
  68 }
  69 #endif
  70
  71
  72 #ifndef HAVE_MEMMOVE
  73  void *memmove(void *dest, const void *src, size_t n)
  74 {
  75         bcopy((char *) src, (char *) dest, n);
  76         return dest;
  77 }
  78 #endif
  79
  80 #ifndef HAVE_STRPBRK
  81 /**
  82  * Find the first occurrence in @p s of any character in @p accept.
  83  *
  84  * Derived from glibc
  85  **/
  86  char *strpbrk(const char *s, const char *accept)
  87 {
  88         while (*s != '\0')  {
  89                 const char *a = accept;
  90                 while (*a != '\0') {
  91                         if (*a++ == *s) return (char *)s;
  92                 }
  93                 ++s;
  94         }
  95
  96         return NULL;
  97 }
  98 #endif
  99
 100
 101 #ifndef HAVE_STRLCPY
 102 /**
 103  * Like strncpy but does not 0 fill the buffer and always null
 104  * terminates.
 105  *
 106  * @param bufsize is the size of the destination buffer.
 107  *
 108  * @return index of the terminating byte.
 109  **/
 110  size_t strlcpy(char *d, const char *s, size_t bufsize)
 111 {
 112         size_t len = strlen(s);
 113         size_t ret = len;
 114         if (bufsize > 0) {
 115                 if (len >= bufsize)
 116                         len = bufsize-1;
 117                 memcpy(d, s, len);
 118                 d[len] = 0;
 119         }
 120         return ret;
 121 }
 122 #endif
 123
 124 #ifndef HAVE_STRLCAT
 125 /**
 126  * Like strncat() but does not 0 fill the buffer and always null
 127  * terminates.
 128  *
 129  * @param bufsize length of the buffer, which should be one more than
 130  * the maximum resulting string length.
 131  **/
 132  size_t strlcat(char *d, const char *s, size_t bufsize)
 133 {
 134         size_t len1 = strlen(d);
 135         size_t len2 = strlen(s);
 136         size_t ret = len1 + len2;
 137
 138         if (len1 < bufsize - 1) {
 139                 if (len2 >= bufsize - len1)
 140                         len2 = bufsize - len1 - 1;
 141                 memcpy(d+len1, s, len2);
 142                 d[len1+len2] = 0;
 143         }
 144         return ret;
 145 }
 146 #endif
 147
 148 /* some systems don't take the 2nd argument */
 149 int sys_gettimeofday(struct timeval *tv)
 150 {
 151 #ifdef HAVE_GETTIMEOFDAY_TZ
 152         return gettimeofday(tv, NULL);
 153 #else
 154         return gettimeofday(tv);
 155 #endif
 156 }
 157
 158 #define HUMANIFY(mult) \
 159         do { \
 160                 if (num >= mult || num <= -mult) { \
 161                         double dnum = (double)num / mult; \
 162                         char units; \
 163                         if (num < 0) \
 164                                 dnum = -dnum; \
 165                         if (dnum < mult) \
 166                                 units = 'K'; \
 167                         else if ((dnum /= mult) < mult) \
 168                                 units = 'M'; \
 169                         else if ((dnum /= mult) < mult) \
 170                                 units = 'G'; \
 171                         else { \
 172                                 dnum /= mult; \
 173                                 units = 'T'; \
 174                         } \
 175                         if (num < 0) \
 176                                 dnum = -dnum; \
 177                         snprintf(bufs[n], sizeof bufs[0], "%.2f%c", dnum, units); \
 178                         return bufs[n]; \
 179                 } \
 180         } while (0)
 181
 182 /* Return the int64 number as a string.  If the human_flag arg is non-zero,
 183  * we may output the number in K, M, G, or T units.  If we don't add a unit
 184  * suffix, we will append the fract string, if it is non-NULL.  We can
 185  * return up to 4 buffers at a time. */
 186 char *do_big_num(int64 num, int human_flag, const char *fract)
 187 {
 188         static char bufs[4][128]; /* more than enough room */
 189         static unsigned int n;
 190         char *s;
 191         int len, negated;
 192
 193         if (human_flag && !number_separator) {
 194                 char buf[32];
 195                 snprintf(buf, sizeof buf, "%f", 3.14);
 196                 if (strchr(buf, '.') != NULL)
 197                         number_separator = ',';
 198                 else
 199                         number_separator = '.';
 200         }
 201
 202         n = (n + 1) % (sizeof bufs / sizeof bufs[0]);
 203
 204         if (human_flag > 1) {
 205                 if (human_flag == 2)
 206                         HUMANIFY(1000);
 207                 else
 208                         HUMANIFY(1024);
 209         }
 210
 211         s = bufs[n] + sizeof bufs[0] - 1;
 212         if (fract) {
 213                 len = strlen(fract);
 214                 s -= len;
 215                 strlcpy(s, fract, len + 1);
 216         } else
 217                 *s = '\0';
 218
 219         len = 0;
 220
 221         if (!num)
 222                 *--s = '0';
 223         if (num < 0) {
 224                 /* A maximum-size negated number can't fit as a positive,
 225                  * so do one digit in negated form to start us off. */
 226                 *--s = (char)(-(num % 10)) + '0';
 227                 num = -(num / 10);
 228                 len++;
 229                 negated = 1;
 230         } else
 231                 negated = 0;
 232
 233         while (num) {
 234                 if (human_flag) {
 235                         if (len == 3) {
 236                                 *--s = number_separator;
 237                                 len = 1;
 238                         } else
 239                                 len++;
 240                 }
 241                 *--s = (char)(num % 10) + '0';
 242                 num /= 10;
 243         }
 244
 245         if (negated)
 246                 *--s = '-';
 247
 248         return s;
 249 }
 250
 251 /* Return the double number as a string.  If the human_flag option is > 1,
 252  * we may output the number in K, M, G, or T units.  The buffer we use for
 253  * our result is either a single static buffer defined here, or a buffer
 254  * we get from do_big_num(). */
 255 char *do_big_dnum(double dnum, int human_flag, int decimal_digits)
 256 {
 257         static char tmp_buf[128];
 258 #if SIZEOF_INT64 >= 8
 259         char *fract;
 260
 261         snprintf(tmp_buf, sizeof tmp_buf, "%.*f", decimal_digits, dnum);
 262
 263         if (!human_flag || (dnum < 1000.0 && dnum > -1000.0))
 264                 return tmp_buf;
 265
 266         for (fract = tmp_buf+1; isDigit(fract); fract++) {}
 267
 268         return do_big_num((int64)dnum, human_flag, fract);
 269 #else
 270         /* A big number might lose digits converting to a too-short int64,
 271          * so let's just return the raw double conversion. */
 272         snprintf(tmp_buf, sizeof tmp_buf, "%.*f", decimal_digits, dnum);
 273         return tmp_buf;
 274 #endif
 275 }