write-or-die.c

   1 #include "cache.h"
   2 #include "config.h"
   3 #include "run-command.h"
   4
   5 /*
   6  * Some cases use stdio, but want to flush after the write
   7  * to get error handling (and to get better interactive
   8  * behaviour - not buffering excessively).
   9  *
  10  * Of course, if the flush happened within the write itself,
  11  * we've already lost the error code, and cannot report it any
  12  * more. So we just ignore that case instead (and hope we get
  13  * the right error code on the flush).
  14  *
  15  * If the file handle is stdout, and stdout is a file, then skip the
  16  * flush entirely since it's not needed.
  17  */
  18 void maybe_flush_or_die(FILE *f, const char *desc)
  19 {
  20         static int skip_stdout_flush = -1;
  21         struct stat st;
  22         char *cp;
  23
  24         if (f == stdout) {
  25                 if (skip_stdout_flush < 0) {
  26                         /* NEEDSWORK: make this a normal Boolean */
  27                         cp = getenv("GIT_FLUSH");
  28                         if (cp)
  29                                 skip_stdout_flush = (atoi(cp) == 0);
  30                         else if ((fstat(fileno(stdout), &st) == 0) &&
  31                                  S_ISREG(st.st_mode))
  32                                 skip_stdout_flush = 1;
  33                         else
  34                                 skip_stdout_flush = 0;
  35                 }
  36                 if (skip_stdout_flush && !ferror(f))
  37                         return;
  38         }
  39         if (fflush(f)) {
  40                 check_pipe(errno);
  41                 die_errno("write failure on '%s'", desc);
  42         }
  43 }
  44
  45 void fprintf_or_die(FILE *f, const char *fmt, ...)
  46 {
  47         va_list ap;
  48         int ret;
  49
  50         va_start(ap, fmt);
  51         ret = vfprintf(f, fmt, ap);
  52         va_end(ap);
  53
  54         if (ret < 0) {
  55                 check_pipe(errno);
  56                 die_errno("write error");
  57         }
  58 }
  59
  60 static int maybe_fsync(int fd)
  61 {
  62         if (use_fsync < 0)
  63                 use_fsync = git_env_bool("GIT_TEST_FSYNC", 1);
  64         if (!use_fsync)
  65                 return 0;
  66
  67         if (fsync_method == FSYNC_METHOD_WRITEOUT_ONLY &&
  68             git_fsync(fd, FSYNC_WRITEOUT_ONLY) >= 0)
  69                 return 0;
  70
  71         return git_fsync(fd, FSYNC_HARDWARE_FLUSH);
  72 }
  73
  74 void fsync_or_die(int fd, const char *msg)
  75 {
  76         if (maybe_fsync(fd) < 0)
  77                 die_errno("fsync error on '%s'", msg);
  78 }
  79
  80 int fsync_component(enum fsync_component component, int fd)
  81 {
  82         if (fsync_components & component)
  83                 return maybe_fsync(fd);
  84         return 0;
  85 }
  86
  87 void fsync_component_or_die(enum fsync_component component, int fd, const char *msg)
  88 {
  89         if (fsync_components & component)
  90                 fsync_or_die(fd, msg);
  91 }
  92
  93 void write_or_die(int fd, const void *buf, size_t count)
  94 {
  95         if (write_in_full(fd, buf, count) < 0) {
  96                 check_pipe(errno);
  97                 die_errno("write error");
  98         }
  99 }
 100
 101 void fwrite_or_die(FILE *f, const void *buf, size_t count)
 102 {
 103         if (fwrite(buf, 1, count, f) != count)
 104                 die_errno("fwrite error");
 105 }
 106
 107 void fflush_or_die(FILE *f)
 108 {
 109         if (fflush(f))
 110                 die_errno("fflush error");
 111 }