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[PATCH v4 3/3] upload-archive: use start_command instead of fork

From
Erik Faye-Lund <kusmabite@gmail.com>
Date
Oct 24, 2011, 16:02 UTC
Message-ID
<1319472131-3968-4-git-send-email-kusmabite@gmail.com>
In-Reply-To
<1319472131-3968-1-git-send-email-kusmabite@gmail.com>

The POSIX-function fork is not supported on Windows. Use our start_command API instead.

As this is the last call-site that depends on the fork-stub in compat/mingw.h, remove that as well.

Add an undocumented flag to git-archive that tells it that the action originated from a remote, so features can be disabled. Thanks to Jeff King for work on this part.

Remove the NOT_MINGW-prereq for t5000, as git-archive --remote now works.

Signed-off-by: Erik Faye-Lund <kusmabite@gmail.com>
Helped-by: Jeff King <peff@peff.net>
---
 builtin/archive.c        |    6 +++-
 builtin/upload-archive.c |   68 ++++++++++++++-------------------------------
 compat/mingw.h           |    2 -
 t/t5000-tar-tree.sh      |   10 +++---
 4 files changed, 31 insertions(+), 55 deletions(-)
diff --git a/builtin/archive.c b/builtin/archive.c
index 931956d..e405566 100644
--- a/builtin/archive.c
+++ b/builtin/archive.c
@@ -87,6 +87,7 @@ int cmd_archive(int argc, const char **argv, const char *prefix)
 	const char *exec = "git-upload-archive";
 	const char *output = NULL;
 	const char *remote = NULL;
+	int is_remote = 0;
 	struct option local_opts[] = {
 		OPT_STRING('o', "output", &output, "file",
 			"write the archive to this file"),
@@ -94,6 +95,9 @@ int cmd_archive(int argc, const char **argv, const char *prefix)
 			"retrieve the archive from remote repository <repo>"),
 		OPT_STRING(0, "exec", &exec, "cmd",
 			"path to the remote git-upload-archive command"),
+		{ OPTION_BOOLEAN, 0, "remote-request", &is_remote, NULL,
+			"indicate we are serving a remote request",
+			PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
 		OPT_END()
 	};
 
@@ -108,5 +112,5 @@ int cmd_archive(int argc, const char **argv, const char *prefix)
 
 	setvbuf(stderr, NULL, _IOLBF, BUFSIZ);
 
-	return write_archive(argc, argv, prefix, 1, output, 0);
+	return write_archive(argc, argv, prefix, 1, output, is_remote);
 }
diff --git a/builtin/upload-archive.c b/builtin/upload-archive.c
index 2d0b383..c57e8bd 100644
--- a/builtin/upload-archive.c
+++ b/builtin/upload-archive.c
@@ -6,6 +6,7 @@
 #include "archive.h"
 #include "pkt-line.h"
 #include "sideband.h"
+#include "run-command.h"
 
 static const char upload_archive_usage[] =
 	"git upload-archive <repo>";
@@ -18,28 +19,17 @@ static const char lostchild[] =
 
 #define MAX_ARGS (64)
 
-static int run_upload_archive(int argc, const char **argv, const char *prefix)
+static void prepare_argv(const char **sent_argv, const char **argv)
 {
-	const char *sent_argv[MAX_ARGS];
 	const char *arg_cmd = "argument ";
 	char *p, buf[4096];
 	int sent_argc;
 	int len;
 
-	if (argc != 2)
-		usage(upload_archive_usage);
-
-	if (strlen(argv[1]) + 1 > sizeof(buf))
-		die("insanely long repository name");
-
-	strcpy(buf, argv[1]); /* enter-repo smudges its argument */
-
-	if (!enter_repo(buf, 0))
-		die("'%s' does not appear to be a git repository", buf);
-
 	/* put received options in sent_argv[] */
-	sent_argc = 1;
-	sent_argv[0] = "git-upload-archive";
+	sent_argc = 2;
+	sent_argv[0] = "archive";
+	sent_argv[1] = "--remote-request";
 	for (p = buf;;) {
 		/* This will die if not enough free space in buf */
 		len = packet_read_line(0, p, (buf + sizeof buf) - p);
@@ -62,9 +52,6 @@ static int run_upload_archive(int argc, const char **argv, const char *prefix)
 		*p++ = 0;
 	}
 	sent_argv[sent_argc] = NULL;
-
-	/* parse all options sent by the client */
-	return write_archive(sent_argc, sent_argv, prefix, 0, NULL, 1);
 }
 
 __attribute__((format (printf, 1, 2)))
@@ -96,38 +83,25 @@ static ssize_t process_input(int child_fd, int band)
 
 int cmd_upload_archive(int argc, const char **argv, const char *prefix)
 {
-	pid_t writer;
-	int fd1[2], fd2[2];
-	/*
-	 * Set up sideband subprocess.
-	 *
-	 * We (parent) monitor and read from child, sending its fd#1 and fd#2
-	 * multiplexed out to our fd#1.  If the child dies, we tell the other
-	 * end over channel #3.
-	 */
-	if (pipe(fd1) < 0 || pipe(fd2) < 0) {
-		int err = errno;
-		packet_write(1, "NACK pipe failed on the remote side\n");
-		die("upload-archive: %s", strerror(err));
-	}
-	writer = fork();
-	if (writer < 0) {
+	const char *sent_argv[MAX_ARGS];
+	struct child_process cld = { sent_argv };
+	cld.out = cld.err = -1;
+	cld.git_cmd = 1;
+
+	if (argc != 2)
+		usage(upload_archive_usage);
+
+	if (!enter_repo(argv[1], 0))
+		die("'%s' does not appear to be a git repository", argv[1]);
+
+	prepare_argv(sent_argv, argv);
+	if (start_command(&cld)) {
 		int err = errno;
 		packet_write(1, "NACK fork failed on the remote side\n");
 		die("upload-archive: %s", strerror(err));
 	}
-	if (!writer) {
-		/* child - connect fd#1 and fd#2 to the pipe */
-		dup2(fd1[1], 1);
-		dup2(fd2[1], 2);
-		close(fd1[1]); close(fd2[1]);
-		close(fd1[0]); close(fd2[0]); /* we do not read from pipe */
-
-		exit(run_upload_archive(argc, argv, prefix));
-	}
 
 	/* parent - read from child, multiplex and send out to fd#1 */
-	close(fd1[1]); close(fd2[1]); /* we do not write to pipe */
 	packet_write(1, "ACK\n");
 	packet_flush(1);
 
@@ -135,9 +109,9 @@ int cmd_upload_archive(int argc, const char **argv, const char *prefix)
 		struct pollfd pfd[2];
 		int status;
 
-		pfd[0].fd = fd1[0];
+		pfd[0].fd = cld.out;
 		pfd[0].events = POLLIN;
-		pfd[1].fd = fd2[0];
+		pfd[1].fd = cld.err;
 		pfd[1].events = POLLIN;
 		if (poll(pfd, 2, -1) < 0) {
 			if (errno != EINTR) {
@@ -156,7 +130,7 @@ int cmd_upload_archive(int argc, const char **argv, const char *prefix)
 			if (process_input(pfd[0].fd, 1))
 				continue;
 
-		if (waitpid(writer, &status, 0) < 0)
+		if (waitpid(cld.pid, &status, 0) < 0)
 			error_clnt("%s", lostchild);
 		else if (!WIFEXITED(status) || WEXITSTATUS(status) > 0)
 			error_clnt("%s", deadchild);
diff --git a/compat/mingw.h b/compat/mingw.h
index fecf0d0..dfb0e87 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -85,8 +85,6 @@ static inline int symlink(const char *oldpath, const char *newpath)
 { errno = ENOSYS; return -1; }
 static inline int fchmod(int fildes, mode_t mode)
 { errno = ENOSYS; return -1; }
-static inline pid_t fork(void)
-{ errno = ENOSYS; return -1; }
 static inline unsigned int alarm(unsigned int seconds)
 { return 0; }
 static inline int fsync(int fd)
diff --git a/t/t5000-tar-tree.sh b/t/t5000-tar-tree.sh
index d906898..889842e 100755
--- a/t/t5000-tar-tree.sh
+++ b/t/t5000-tar-tree.sh
@@ -96,7 +96,7 @@ test_expect_success 'git archive with --output' \
     'git archive --output=b4.tar HEAD &&
     test_cmp b.tar b4.tar'
 
-test_expect_success NOT_MINGW 'git archive --remote' \
+test_expect_success 'git archive --remote' \
     'git archive --remote=. HEAD >b5.tar &&
     test_cmp b.tar b5.tar'
 
@@ -266,7 +266,7 @@ test_expect_success 'archive --list mentions user filter' '
 	grep "^bar\$" output
 '
 
-test_expect_success NOT_MINGW 'archive --list shows only enabled remote filters' '
+test_expect_success 'archive --list shows only enabled remote filters' '
 	git archive --list --remote=. >output &&
 	! grep "^tar\.foo\$" output &&
 	grep "^bar\$" output
@@ -298,7 +298,7 @@ test_expect_success 'extension matching requires dot' '
 	test_cmp b.tar config-implicittar.foo
 '
 
-test_expect_success NOT_MINGW 'only enabled filters are available remotely' '
+test_expect_success 'only enabled filters are available remotely' '
 	test_must_fail git archive --remote=. --format=tar.foo HEAD \
 		>remote.tar.foo &&
 	git archive --remote=. --format=bar >remote.bar HEAD &&
@@ -341,12 +341,12 @@ test_expect_success GZIP,GUNZIP 'extract tgz file' '
 	test_cmp b.tar j.tar
 '
 
-test_expect_success GZIP,NOT_MINGW 'remote tar.gz is allowed by default' '
+test_expect_success GZIP 'remote tar.gz is allowed by default' '
 	git archive --remote=. --format=tar.gz HEAD >remote.tar.gz &&
 	test_cmp j.tgz remote.tar.gz
 '
 
-test_expect_success GZIP,NOT_MINGW 'remote tar.gz can be disabled' '
+test_expect_success GZIP 'remote tar.gz can be disabled' '
 	git config tar.tar.gz.remote false &&
 	test_must_fail git archive --remote=. --format=tar.gz HEAD \
 		>remote.tar.gz

-- 
1.7.7.msysgit.1.1.g7b316
Previous: Erik Faye-LundNext: Jeff King
Message 4 of 17 in “port upload-archive to Windows”
  1. 0/3 port upload-archive to WindowsErik Faye-Lund, Oct 24, 2011
  2. 1/3 mingw: move poll out of sys-folderErik Faye-Lund, Oct 24, 2011
  3. 2/3 compat/win32/poll.c: upgrade from upstreamErik Faye-Lund, Oct 24, 2011
  4. 3/3 upload-archive: use start_command instead of forkErik Faye-Lund, Oct 24, 2011
  5. Jeff KingOct 24, 2011
  6. Thomas RastNov 15, 2011
  7. Jeff KingNov 15, 2011
  8. Thomas RastNov 15, 2011
  9. Jeff KingNov 15, 2011
  10. Erik Faye-LundNov 15, 2011
  11. Jeff KingNov 15, 2011
  12. Junio C HamanoNov 15, 2011
  13. Jeff KingNov 15, 2011
  14. 1/2 upload-archive: drop extra argument to prepare_argvJeff King, Nov 15, 2011
  15. upload-archive: use argv_array for sent parametersJeff King, Nov 15, 2011
  16. Jeff KingNov 15, 2011
  17. Andreas SchwabNov 15, 2011

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