git/write-or-die.c
Junio C Hamano b40ba17e44 write-or-die: fix the polarity of GIT_FLUSH environment variable
When GIT_FLUSH is set to 1, true, on, yes, then we should disable
skip_stdout_flush, but the conversion somehow did the opposite.

With the understanding of the original motivation behind "skip" in
06f59e9f (Don't fflush(stdout) when it's not helpful, 2007-06-29),
we can sympathize with the current naming (we wanted to avoid
useless flushing of stdout by default, with an escape hatch to
always flush), but it is still not a good excuse.

Retire the "skip_stdout_flush" variable and replace it with "flush_stdout"
that tells if we do or do not want to run fflush().

Reported-by: Xiaoguang WANG <wxiaoguang@gmail.com>
Helped-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-02-13 11:57:28 -08:00

110 lines
2.3 KiB
C

#include "git-compat-util.h"
#include "parse.h"
#include "run-command.h"
#include "write-or-die.h"
/*
* Some cases use stdio, but want to flush after the write
* to get error handling (and to get better interactive
* behaviour - not buffering excessively).
*
* Of course, if the flush happened within the write itself,
* we've already lost the error code, and cannot report it any
* more. So we just ignore that case instead (and hope we get
* the right error code on the flush).
*
* If the file handle is stdout, and stdout is a file, then skip the
* flush entirely since it's not needed.
*/
void maybe_flush_or_die(FILE *f, const char *desc)
{
if (f == stdout) {
static int force_flush_stdout = -1;
if (force_flush_stdout < 0) {
force_flush_stdout = git_env_bool("GIT_FLUSH", -1);
if (force_flush_stdout < 0) {
struct stat st;
if (fstat(fileno(stdout), &st))
force_flush_stdout = 1;
else
force_flush_stdout = !S_ISREG(st.st_mode);
}
}
if (!force_flush_stdout && !ferror(f))
return;
}
if (fflush(f)) {
check_pipe(errno);
die_errno("write failure on '%s'", desc);
}
}
void fprintf_or_die(FILE *f, const char *fmt, ...)
{
va_list ap;
int ret;
va_start(ap, fmt);
ret = vfprintf(f, fmt, ap);
va_end(ap);
if (ret < 0) {
check_pipe(errno);
die_errno("write error");
}
}
static int maybe_fsync(int fd)
{
if (use_fsync < 0)
use_fsync = git_env_bool("GIT_TEST_FSYNC", 1);
if (!use_fsync)
return 0;
if (fsync_method == FSYNC_METHOD_WRITEOUT_ONLY &&
git_fsync(fd, FSYNC_WRITEOUT_ONLY) >= 0)
return 0;
return git_fsync(fd, FSYNC_HARDWARE_FLUSH);
}
void fsync_or_die(int fd, const char *msg)
{
if (maybe_fsync(fd) < 0)
die_errno("fsync error on '%s'", msg);
}
int fsync_component(enum fsync_component component, int fd)
{
if (fsync_components & component)
return maybe_fsync(fd);
return 0;
}
void fsync_component_or_die(enum fsync_component component, int fd, const char *msg)
{
if (fsync_components & component)
fsync_or_die(fd, msg);
}
void write_or_die(int fd, const void *buf, size_t count)
{
if (write_in_full(fd, buf, count) < 0) {
check_pipe(errno);
die_errno("write error");
}
}
void fwrite_or_die(FILE *f, const void *buf, size_t count)
{
if (fwrite(buf, 1, count, f) != count)
die_errno("fwrite error");
}
void fflush_or_die(FILE *f)
{
if (fflush(f))
die_errno("fflush error");
}