Re: git archive, cygwin, and --git-dir vs --remote
Show 18 quoted lines
> I'm using git on cygwin, and am confused by behavior from git archive.
>
> git --version
> git version 1.6.1.2
>
> This command works as expected:
> git --git-dir=/cygdrive/w archive --format=tar --verbose --prefix=tmp/
> HEAD | tar -xpf -
> The latest copy is retrieved and dumped to the tmp subdirectory.
>
> However, I first went down the path of using the --remote option, as
> described in the git-archive man page:
> git archive --format=tar --verbose --prefix=tmp/ --remote=/cygdrive/w
> HEAD | tar -xpf -
>
> When I use the --remote branch it seems to create the same files. But
> then rather than exiting it hangs out until I kill the process, using
> about the same CPU % as it did when creating files.
That's strange. It seems that poll() reports that there is data to read from the child (which is running git-upload-archive), even though it already called exit().
The following patch works around this issue by terminating the otherwise endless loop after read() returned nothing for the thousandth time in a row. I'm not sure that there's really no way to get a thousand empty reads without the child being done, though.
builtin-upload-archive.c | 14 ++++++++++----
1 files changed, 10 insertions(+), 4 deletions(-)
diff --git a/builtin-upload-archive.c b/builtin-upload-archive.c
index 0206b41..3d7b11b 100644
--- a/builtin-upload-archive.c
+++ b/builtin-upload-archive.c
@@ -17,6 +17,7 @@ static const char lostchild[] =
"git upload-archive: archiver process was lost";
#define MAX_ARGS (64)
+#define MAX_EMPTY_READS (1000)
static int run_upload_archive(int argc, const char **argv, const char *prefix)
{
@@ -80,10 +81,11 @@ static void error_clnt(const char *fmt, ...)
die("sent error to the client: %s", buf);
}
-static void process_input(int child_fd, int band)
+static void process_input(int child_fd, int band, int *empty_reads)
{
char buf[16384];
ssize_t sz = read(child_fd, buf, sizeof(buf));
+ *empty_reads = sz ? 0 : *empty_reads + 1;
if (sz < 0) {
if (errno != EAGAIN && errno != EINTR)
error_clnt("read error: %s\n", strerror(errno));
@@ -96,6 +98,8 @@ int cmd_upload_archive(int argc, const char **argv, const char *prefix)
{
pid_t writer;
int fd1[2], fd2[2];
+ int empty_reads_1 = 0;
+ int empty_reads_2 = 0;
/*
* Set up sideband subprocess.
*
@@ -147,12 +151,14 @@ int cmd_upload_archive(int argc, const char **argv, const char *prefix)
}
if (pfd[0].revents & POLLIN)
/* Data stream ready */
- process_input(pfd[0].fd, 1);
+ process_input(pfd[0].fd, 1, &empty_reads_1);
if (pfd[1].revents & POLLIN)
/* Status stream ready */
- process_input(pfd[1].fd, 2);
+ process_input(pfd[1].fd, 2, &empty_reads_2);
/* Always finish to read data when available */
- if ((pfd[0].revents | pfd[1].revents) & POLLIN)
+ if (((pfd[0].revents | pfd[1].revents) & POLLIN) &&
+ empty_reads_1 <= MAX_EMPTY_READS &&
+ empty_reads_2 <= MAX_EMPTY_READS)
continue;
if (waitpid(writer, &status, 0) < 0)