write_or_die.con commit builtin/help.c: add --guide option (65f9835)
   1#include "cache.h"
   2
   3static void check_pipe(int err)
   4{
   5        if (err == EPIPE) {
   6                signal(SIGPIPE, SIG_DFL);
   7                raise(SIGPIPE);
   8                /* Should never happen, but just in case... */
   9                exit(141);
  10        }
  11}
  12
  13/*
  14 * Some cases use stdio, but want to flush after the write
  15 * to get error handling (and to get better interactive
  16 * behaviour - not buffering excessively).
  17 *
  18 * Of course, if the flush happened within the write itself,
  19 * we've already lost the error code, and cannot report it any
  20 * more. So we just ignore that case instead (and hope we get
  21 * the right error code on the flush).
  22 *
  23 * If the file handle is stdout, and stdout is a file, then skip the
  24 * flush entirely since it's not needed.
  25 */
  26void maybe_flush_or_die(FILE *f, const char *desc)
  27{
  28        static int skip_stdout_flush = -1;
  29        struct stat st;
  30        char *cp;
  31
  32        if (f == stdout) {
  33                if (skip_stdout_flush < 0) {
  34                        cp = getenv("GIT_FLUSH");
  35                        if (cp)
  36                                skip_stdout_flush = (atoi(cp) == 0);
  37                        else if ((fstat(fileno(stdout), &st) == 0) &&
  38                                 S_ISREG(st.st_mode))
  39                                skip_stdout_flush = 1;
  40                        else
  41                                skip_stdout_flush = 0;
  42                }
  43                if (skip_stdout_flush && !ferror(f))
  44                        return;
  45        }
  46        if (fflush(f)) {
  47                check_pipe(errno);
  48                die_errno("write failure on '%s'", desc);
  49        }
  50}
  51
  52void fsync_or_die(int fd, const char *msg)
  53{
  54        if (fsync(fd) < 0) {
  55                die_errno("fsync error on '%s'", msg);
  56        }
  57}
  58
  59void write_or_die(int fd, const void *buf, size_t count)
  60{
  61        if (write_in_full(fd, buf, count) < 0) {
  62                check_pipe(errno);
  63                die_errno("write error");
  64        }
  65}
  66
  67int write_or_whine_pipe(int fd, const void *buf, size_t count, const char *msg)
  68{
  69        if (write_in_full(fd, buf, count) < 0) {
  70                check_pipe(errno);
  71                fprintf(stderr, "%s: write error (%s)\n",
  72                        msg, strerror(errno));
  73                return 0;
  74        }
  75
  76        return 1;
  77}
  78
  79int write_or_whine(int fd, const void *buf, size_t count, const char *msg)
  80{
  81        if (write_in_full(fd, buf, count) < 0) {
  82                fprintf(stderr, "%s: write error (%s)\n",
  83                        msg, strerror(errno));
  84                return 0;
  85        }
  86
  87        return 1;
  88}