[PATCH 02/14] Use start_command() in git_connect() instead of explicit fork/exec.

From

Johannes Sixt <johannes.sixt@telecom.at>

Date

Oct 13, 2007, 20:06 UTC

Message-ID

<1192305984-22594-3-git-send-email-johannes.sixt@telecom.at>

In-Reply-To

<1192305984-22594-2-git-send-email-johannes.sixt@telecom.at>

Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
---
 connect.c |  108 ++++++++++++++++++++++++++++--------------------------------
 1 files changed, 50 insertions(+), 58 deletions(-)

diff --git a/connect.c b/connect.c
index b156f92..21597bf 100644
--- a/connect.c
+++ b/connect.c
@@ -484,11 +484,15 @@ struct child_process *git_connect(int fd[2], char *url,
 	char *host, *path = url;
 	char *end;
 	int c;
-	int pipefd[2][2];
 	struct child_process *conn;
 	enum protocol protocol = PROTO_LOCAL;
 	int free_path = 0;
 	char *port = NULL;
+	const char **arg;
+	char command[MAX_CMD_LEN];
+	char *posn = command;
+	int size = MAX_CMD_LEN;
+	int of = 0;
 
 	/* Without this we cannot rely on waitpid() to tell
 	 * what happened to our children.
@@ -574,62 +578,51 @@ struct child_process *git_connect(int fd[2], char *url,
 		return NULL;
 	}
 
-	if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
-		die("unable to create pipe pair for communication");
 	conn = xcalloc(1, sizeof(*conn));
-	conn->pid = fork();
-	if (conn->pid < 0)
-		die("unable to fork");
-	if (!conn->pid) {
-		char command[MAX_CMD_LEN];
-		char *posn = command;
-		int size = MAX_CMD_LEN;
-		int of = 0;
-
-		of |= add_to_string(&posn, &size, prog, 0);
-		of |= add_to_string(&posn, &size, " ", 0);
-		of |= add_to_string(&posn, &size, path, 1);
-
-		if (of)
-			die("command line too long");
-
-		dup2(pipefd[1][0], 0);
-		dup2(pipefd[0][1], 1);
-		close(pipefd[0][0]);
-		close(pipefd[0][1]);
-		close(pipefd[1][0]);
-		close(pipefd[1][1]);
-		if (protocol == PROTO_SSH) {
-			const char *ssh, *ssh_basename;
-			ssh = getenv("GIT_SSH");
-			if (!ssh) ssh = "ssh";
-			ssh_basename = strrchr(ssh, '/');
-			if (!ssh_basename)
-				ssh_basename = ssh;
-			else
-				ssh_basename++;
 
-			if (!port)
-				execlp(ssh, ssh_basename, host, command, NULL);
-			else
-				execlp(ssh, ssh_basename, "-p", port, host,
-				       command, NULL);
-		}
-		else {
-			unsetenv(ALTERNATE_DB_ENVIRONMENT);
-			unsetenv(DB_ENVIRONMENT);
-			unsetenv(GIT_DIR_ENVIRONMENT);
-			unsetenv(GIT_WORK_TREE_ENVIRONMENT);
-			unsetenv(GRAFT_ENVIRONMENT);
-			unsetenv(INDEX_ENVIRONMENT);
-			execlp("sh", "sh", "-c", command, NULL);
+	of |= add_to_string(&posn, &size, prog, 0);
+	of |= add_to_string(&posn, &size, " ", 0);
+	of |= add_to_string(&posn, &size, path, 1);
+
+	if (of)
+		die("command line too long");
+
+	conn->in = conn->out = -1;
+	conn->argv = arg = xcalloc(6, sizeof(*arg));
+	if (protocol == PROTO_SSH) {
+		const char *ssh = getenv("GIT_SSH");
+		if (!ssh) ssh = "ssh";
+
+		*arg++ = ssh;
+		if (port) {
+			*arg++ = "-p";
+			*arg++ = port;
 		}
-		die("exec failed");
+		*arg++ = host;
+	}
+	else {
+		/* remove these from the environment */
+		const char *env[] = {
+			ALTERNATE_DB_ENVIRONMENT,
+			DB_ENVIRONMENT,
+			GIT_DIR_ENVIRONMENT,
+			GIT_WORK_TREE_ENVIRONMENT,
+			GRAFT_ENVIRONMENT,
+			INDEX_ENVIRONMENT,
+			NULL
+		};
+		conn->env = env;
+		*arg++ = "sh";
+		*arg++ = "-c";
 	}
-	fd[0] = pipefd[0][0];
-	fd[1] = pipefd[1][1];
-	close(pipefd[0][1]);
-	close(pipefd[1][0]);
+	*arg++ = command;
+	*arg = NULL;
+
+	if (start_command(conn))
+		die("unable to fork");
+
+	fd[0] = conn->out; /* read from child's stdout */
+	fd[1] = conn->in;  /* write to child's stdin */
 	if (free_path)
 		free(path);
 	return conn;
@@ -637,13 +630,12 @@ struct child_process *git_connect(int fd[2], char *url,
 
 int finish_connect(struct child_process *conn)
 {
+	int code;
 	if (conn == NULL)
 		return 0;
 
-	while (waitpid(conn->pid, NULL, 0) < 0) {
-		if (errno != EINTR)
-			return -1;
-	}
+	code = finish_command(conn);
+	free(conn->argv);
 	free(conn);
-	return 0;
+	return code;
 }

-- 
1.5.3.3.1134.gee562