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[PATCH v2 4/4] upload-archive: use start_command instead of fork

From
Erik Faye-Lund <kusmabite@gmail.com>
Date
Jul 18, 2011, 18:08 UTC
Message-ID
<1311012516-4836-5-git-send-email-kusmabite@gmail.com>
In-Reply-To
<1311012516-4836-1-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.

Signed-off-by: Erik Faye-Lund <kusmabite@gmail.com>
---
 builtin/upload-archive.c |   65 +++++++++++++--------------------------------
 compat/mingw.h           |    2 -
 2 files changed, 19 insertions(+), 48 deletions(-)
diff --git a/builtin/upload-archive.c b/builtin/upload-archive.c
index 73f788e..0c192b5 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 +19,16 @@ 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_argv[0] = "archive";
 	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 +51,6 @@ 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);
 }
 
 __attribute__((format (printf, 1, 2)))
@@ -96,38 +82,25 @@ 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 +108,9 @@ 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 +129,7 @@ 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 ce9dd98..9cb6eb9 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)
-- 
1.7.6.135.g378e9
Previous: Erik Faye-LundNext: Junio C Hamano
Message 5 of 33 in “port upload-archive to Windows”
  1. 0/4 port upload-archive to WindowsErik Faye-Lund, Jul 18, 2011
  2. 1/4 compat/win32/sys/poll.c: upgrade from upstreamErik Faye-Lund, Jul 18, 2011
  3. 2/4 mingw: fix compilation of poll-emulationErik Faye-Lund, Jul 18, 2011
  4. 3/4 enter_repo: do not modify inputErik Faye-Lund, Jul 18, 2011
  5. 4/4 upload-archive: use start_command instead of forkErik Faye-Lund, Jul 18, 2011
  6. Junio C HamanoJul 19, 2011
  7. Erik Faye-LundJul 28, 2011
  8. Jeff KingJul 28, 2011
  9. Jeff KingJul 28, 2011
  10. Jeff KingJul 28, 2011
  11. Erik Faye-LundAug 1, 2011
  12. Jeff KingAug 1, 2011
  13. Erik Faye-LundAug 1, 2011
  14. Jeff KingAug 1, 2011
  15. René ScharfeAug 1, 2011
  16. Johannes SixtAug 1, 2011
  17. René ScharfeAug 1, 2011
  18. René ScharfeAug 1, 2011
  19. Jeff KingAug 2, 2011
  20. René ScharfeAug 2, 2011
  21. Jeff KingAug 2, 2011
  22. Johannes SixtAug 2, 2011
  23. Jeff KingAug 3, 2011
  24. René ScharfeAug 6, 2011
  25. Johannes SixtAug 7, 2011
  26. Jeff KingAug 7, 2011
  27. René ScharfeAug 8, 2011
  28. Jeff KingAug 9, 2011
  29. René ScharfeAug 9, 2011
  30. Jeff KingAug 9, 2011
  31. Erik Faye-LundSep 29, 2011
  32. René ScharfeSep 29, 2011
  33. Erik Faye-LundSep 29, 2011

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