write_or_die.c

   1 #include "cache.h"
   2
   3 /*
   4  * Some cases use stdio, but want to flush after the write
   5  * to get error handling (and to get better interactive
   6  * behaviour - not buffering excessively).
   7  *
   8  * Of course, if the flush happened within the write itself,
   9  * we've already lost the error code, and cannot report it any
  10  * more. So we just ignore that case instead (and hope we get
  11  * the right error code on the flush).
  12  *
  13  * If the file handle is stdout, and stdout is a file, then skip the
  14  * flush entirely since it's not needed.
  15  */
  16 void maybe_flush_or_die(FILE *f, const char *desc)
  17 {
  18         static int skip_stdout_flush = -1;
  19         struct stat st;
  20         char *cp;
  21
  22         if (f == stdout) {
  23                 if (skip_stdout_flush < 0) {
  24                         cp = getenv("GIT_FLUSH");
  25                         if (cp)
  26                                 skip_stdout_flush = (atoi(cp) == 0);
  27                         else if ((fstat(fileno(stdout), &st) == 0) &&
  28                                  S_ISREG(st.st_mode))
  29                                 skip_stdout_flush = 1;
  30                         else
  31                                 skip_stdout_flush = 0;
  32                 }
  33                 if (skip_stdout_flush && !ferror(f))
  34                         return;
  35         }
  36         if (fflush(f)) {
  37                 if (errno == EPIPE)
  38                         exit(0);
  39                 die_errno("write failure on '%s'", desc);
  40         }
  41 }
  42
  43 void fsync_or_die(int fd, const char *msg)
  44 {
  45         if (fsync(fd) < 0) {
  46                 die_errno("fsync error on '%s'", msg);
  47         }
  48 }
  49
  50 void write_or_die(int fd, const void *buf, size_t count)
  51 {
  52         if (write_in_full(fd, buf, count) < 0) {
  53                 if (errno == EPIPE)
  54                         exit(0);
  55                 die_errno("write error");
  56         }
  57 }
  58
  59 int write_or_whine_pipe(int fd, const void *buf, size_t count, const char *msg)
  60 {
  61         if (write_in_full(fd, buf, count) < 0) {
  62                 if (errno == EPIPE)
  63                         exit(0);
  64                 fprintf(stderr, "%s: write error (%s)\n",
  65                         msg, strerror(errno));
  66                 return 0;
  67         }
  68
  69         return 1;
  70 }
  71
  72 int write_or_whine(int fd, const void *buf, size_t count, const char *msg)
  73 {
  74         if (write_in_full(fd, buf, count) < 0) {
  75                 fprintf(stderr, "%s: write error (%s)\n",
  76                         msg, strerror(errno));
  77                 return 0;
  78         }
  79
  80         return 1;
  81 }