The Tcpdump Group git mirrors - libpcap/blob - missing/win_snprintf.c

   1 #include <stdio.h>
   2 #include <stdarg.h>
   3
   4 #include "portability.h"
   5
   6 int
   7 pcap_vsnprintf(char *str, size_t str_size, const char *format, va_list args)
   8 {
   9         int ret;
  10
  11         ret = _vsnprintf_s(str, str_size, _TRUNCATE, format, args);
  12
  13         /*
  14          * XXX - _vsnprintf() and _snprintf() do *not* guarantee
  15          * that str is null-terminated, but C99's vsnprintf()
  16          * and snprintf() do, and we want to offer C99 behavior,
  17          * so forcibly null-terminate the string.
  18          *
  19          * We don't, however, offer C99 behavior for the return
  20          * value; _vsnprintf_s() returns -1, not the number of
  21          * characters that would have been put into the buffer
  22          * had it been large enough, if the string is truncated.
  23          * The only way to get that value is to use _vscprintf();
  24          * getting that count isn't worth the re-formatting.
  25          *
  26          * XXX - does _vsnprintf_s() return -1 on a formatting
  27          * error?
  28          */
  29         str[str_size - 1] = '\0';
  30         return (ret);
  31 }
  32
  33 int
  34 pcap_snprintf(char *str, size_t str_size, const char *format, ...)
  35 {
  36         va_list args;
  37         int ret;
  38
  39         va_start(args, format);
  40         ret = pcap_vsnprintf(str, str_size, format, args);
  41         va_end(args);
  42         return (ret);
  43 }