git/fetch-clone.c
Nicolas Pitre 9ac13ec941 atomic write for sideband remote messages
It has been a few times that I ended up with such a confusing display:

|remote: Generating pack...
|remote: Done counting 17 objects.
|remote: Result has 9 objects.
|remote: Deltifying 9 objects.
|remote:  100% (9/9) done
|remote: Unpacking 9 objects
|Total 9, written 9 (delta 8), reused 0 (delta 0)
| 100% (9/9) done

The confusion can be avoided in most cases by writing the remote message
in one go to prevent interleacing with local messages.  The buffer
declaration has been moved inside recv_sideband() to avoid extra string
copies.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-10-11 11:13:01 -07:00

277 lines
6.3 KiB
C

#include "cache.h"
#include "exec_cmd.h"
#include "pkt-line.h"
#include "sideband.h"
#include <sys/wait.h>
#include <sys/time.h>
static int finish_pack(const char *pack_tmp_name, const char *me)
{
int pipe_fd[2];
pid_t pid;
char idx[PATH_MAX];
char final[PATH_MAX];
char hash[41];
unsigned char sha1[20];
char *cp;
int err = 0;
if (pipe(pipe_fd) < 0)
die("%s: unable to set up pipe", me);
strcpy(idx, pack_tmp_name); /* ".git/objects/pack-XXXXXX" */
cp = strrchr(idx, '/');
memcpy(cp, "/pidx", 5);
pid = fork();
if (pid < 0)
die("%s: unable to fork off git-index-pack", me);
if (!pid) {
close(0);
dup2(pipe_fd[1], 1);
close(pipe_fd[0]);
close(pipe_fd[1]);
execl_git_cmd("index-pack", "-o", idx, pack_tmp_name, NULL);
error("cannot exec git-index-pack <%s> <%s>",
idx, pack_tmp_name);
exit(1);
}
close(pipe_fd[1]);
if (read(pipe_fd[0], hash, 40) != 40) {
error("%s: unable to read from git-index-pack", me);
err = 1;
}
close(pipe_fd[0]);
for (;;) {
int status, code;
if (waitpid(pid, &status, 0) < 0) {
if (errno == EINTR)
continue;
error("waitpid failed (%s)", strerror(errno));
goto error_die;
}
if (WIFSIGNALED(status)) {
int sig = WTERMSIG(status);
error("git-index-pack died of signal %d", sig);
goto error_die;
}
if (!WIFEXITED(status)) {
error("git-index-pack died of unnatural causes %d",
status);
goto error_die;
}
code = WEXITSTATUS(status);
if (code) {
error("git-index-pack died with error code %d", code);
goto error_die;
}
if (err)
goto error_die;
break;
}
hash[40] = 0;
if (get_sha1_hex(hash, sha1)) {
error("git-index-pack reported nonsense '%s'", hash);
goto error_die;
}
/* Now we have pack in pack_tmp_name[], and
* idx in idx[]; rename them to their final names.
*/
snprintf(final, sizeof(final),
"%s/pack/pack-%s.pack", get_object_directory(), hash);
move_temp_to_file(pack_tmp_name, final);
chmod(final, 0444);
snprintf(final, sizeof(final),
"%s/pack/pack-%s.idx", get_object_directory(), hash);
move_temp_to_file(idx, final);
chmod(final, 0444);
return 0;
error_die:
unlink(idx);
unlink(pack_tmp_name);
exit(1);
}
static pid_t setup_sideband(int sideband, const char *me, int fd[2], int xd[2])
{
pid_t side_pid;
if (!sideband) {
fd[0] = xd[0];
fd[1] = xd[1];
return 0;
}
/* xd[] is talking with upload-pack; subprocess reads from
* xd[0], spits out band#2 to stderr, and feeds us band#1
* through our fd[0].
*/
if (pipe(fd) < 0)
die("%s: unable to set up pipe", me);
side_pid = fork();
if (side_pid < 0)
die("%s: unable to fork off sideband demultiplexer", me);
if (!side_pid) {
/* subprocess */
close(fd[0]);
if (xd[0] != xd[1])
close(xd[1]);
if (recv_sideband(me, xd[0], fd[1], 2))
exit(1);
exit(0);
}
close(xd[0]);
close(fd[1]);
fd[1] = xd[1];
return side_pid;
}
int receive_unpack_pack(int xd[2], const char *me, int quiet, int sideband)
{
int status;
pid_t pid, side_pid;
int fd[2];
side_pid = setup_sideband(sideband, me, fd, xd);
pid = fork();
if (pid < 0)
die("%s: unable to fork off git-unpack-objects", me);
if (!pid) {
dup2(fd[0], 0);
close(fd[0]);
close(fd[1]);
execl_git_cmd("unpack-objects", quiet ? "-q" : NULL, NULL);
die("git-unpack-objects exec failed");
}
close(fd[0]);
close(fd[1]);
while (waitpid(pid, &status, 0) < 0) {
if (errno != EINTR)
die("waiting for git-unpack-objects: %s",
strerror(errno));
}
if (WIFEXITED(status)) {
int code = WEXITSTATUS(status);
if (code)
die("git-unpack-objects died with error code %d",
code);
return 0;
}
if (WIFSIGNALED(status)) {
int sig = WTERMSIG(status);
die("git-unpack-objects died of signal %d", sig);
}
die("git-unpack-objects died of unnatural causes %d", status);
}
/*
* We average out the download speed over this many "events", where
* an event is a minimum of about half a second. That way, we get
* a reasonably stable number.
*/
#define NR_AVERAGE (4)
/*
* A "binary msec" is a power-of-two-msec, aka 1/1024th of a second.
* Keeping the time in that format means that "bytes / msecs" means
* the same as kB/s (modulo rounding).
*
* 1000512 is a magic number (usecs in a second, rounded up by half
* of 1024, to make "rounding" come out right ;)
*/
#define usec_to_binarymsec(x) ((int)(x) / (1000512 >> 10))
int receive_keep_pack(int xd[2], const char *me, int quiet, int sideband)
{
char tmpfile[PATH_MAX];
int ofd, ifd, fd[2];
unsigned long total;
static struct timeval prev_tv;
struct average {
unsigned long bytes;
unsigned long time;
} download[NR_AVERAGE] = { {0, 0}, };
unsigned long avg_bytes, avg_time;
int idx = 0;
setup_sideband(sideband, me, fd, xd);
ifd = fd[0];
snprintf(tmpfile, sizeof(tmpfile),
"%s/pack/tmp-XXXXXX", get_object_directory());
ofd = mkstemp(tmpfile);
if (ofd < 0)
return error("unable to create temporary file %s", tmpfile);
gettimeofday(&prev_tv, NULL);
total = 0;
avg_bytes = 0;
avg_time = 0;
while (1) {
char buf[8192];
ssize_t sz, wsz, pos;
sz = read(ifd, buf, sizeof(buf));
if (sz == 0)
break;
if (sz < 0) {
if (errno != EINTR && errno != EAGAIN) {
error("error reading pack (%s)", strerror(errno));
close(ofd);
unlink(tmpfile);
return -1;
}
sz = 0;
}
pos = 0;
while (pos < sz) {
wsz = write(ofd, buf + pos, sz - pos);
if (wsz < 0) {
error("error writing pack (%s)",
strerror(errno));
close(ofd);
unlink(tmpfile);
return -1;
}
pos += wsz;
}
total += sz;
if (!quiet) {
static unsigned long last;
struct timeval tv;
unsigned long diff = total - last;
/* not really "msecs", but a power-of-two millisec (1/1024th of a sec) */
unsigned long msecs;
gettimeofday(&tv, NULL);
msecs = tv.tv_sec - prev_tv.tv_sec;
msecs <<= 10;
msecs += usec_to_binarymsec(tv.tv_usec - prev_tv.tv_usec);
if (msecs > 500) {
prev_tv = tv;
last = total;
/* Update averages ..*/
avg_bytes += diff;
avg_time += msecs;
avg_bytes -= download[idx].bytes;
avg_time -= download[idx].time;
download[idx].bytes = diff;
download[idx].time = msecs;
idx++;
if (idx >= NR_AVERAGE)
idx = 0;
fprintf(stderr, "%4lu.%03luMB (%lu kB/s) \r",
total >> 20,
1000*((total >> 10) & 1023)>>10,
avg_bytes / avg_time );
}
}
}
close(ofd);
return finish_pack(tmpfile, me);
}