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[PATCH 2/8] connect: move no_fork fallback to git_tcp_connect

From
Jonathan Nieder <jrnieder@gmail.com>
Date
Nov 20, 2017, 21:22 UTC
Message-ID
<20171120212254.ab6ata2mwvdbbdmw@aiede.mtv.corp.google.com>
In-Reply-To
<20171120212134.lh2l4drdzu6fh5g2@aiede.mtv.corp.google.com>
git_connect has the structure
	struct child_process *conn = &no_fork;
	...
	switch (protocol) {
	case PROTO_GIT:
		if (git_use_proxy(hostandport))
			conn = git_proxy_connect(fd, hostandport);
		else
			git_tcp_connect(fd, hostandport, flags);
		...
		break;
	case PROTO_SSH:
		conn = xmalloc(sizeof(*conn));
		child_process_init(conn);
		argv_array_push(&conn->args, ssh);
		...
		break;
	...
	return conn;

In all cases except the git_tcp_connect case, conn is explicitly assigned a value. Make the code clearer by explicitly assigning 'conn = &no_fork' in the tcp case and eliminating the default so the compiler can ensure conn is always correctly assigned.

Noticed-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
---
 connect.c | 36 +++++++++++++++++++++---------------
 1 file changed, 21 insertions(+), 15 deletions(-)
diff --git a/connect.c b/connect.c
index 7fbd396b35..aa994d1518 100644
--- a/connect.c
+++ b/connect.c
@@ -582,12 +582,25 @@ static int git_tcp_connect_sock(char *host, int flags)
 #endif /* NO_IPV6 */
 
 
-static void git_tcp_connect(int fd[2], char *host, int flags)
+/*
+ * Dummy child_process returned by git_connect() if the transport protocol
+ * does not need fork(2).
+ */
+static struct child_process no_fork = CHILD_PROCESS_INIT;
+
+int git_connection_is_socket(struct child_process *conn)
+{
+	return conn == &no_fork;
+}
+
+static struct child_process *git_tcp_connect(int fd[2], char *host, int flags)
 {
 	int sockfd = git_tcp_connect_sock(host, flags);
 
 	fd[0] = sockfd;
 	fd[1] = dup(sockfd);
+
+	return &no_fork;
 }
 
 
@@ -761,8 +774,6 @@ static enum protocol parse_connect_url(const char *url_orig, char **ret_host,
 	return protocol;
 }
 
-static struct child_process no_fork = CHILD_PROCESS_INIT;
-
 static const char *get_ssh_command(void)
 {
 	const char *ssh;
@@ -851,11 +862,11 @@ static enum ssh_variant determine_ssh_variant(const char *ssh_command,
 }
 
 /*
- * This returns a dummy child_process if the transport protocol does not
- * need fork(2), or a struct child_process object if it does.  Once done,
- * finish the connection with finish_connect() with the value returned from
- * this function (it is safe to call finish_connect() with NULL to support
- * the former case).
+ * This returns the dummy child_process `no_fork` if the transport protocol
+ * does not need fork(2), or a struct child_process object if it does.  Once
+ * done, finish the connection with finish_connect() with the value returned
+ * from this function (it is safe to call finish_connect() with NULL to
+ * support the former case).
  *
  * If it returns, the connect is successful; it just dies on errors (this
  * will hopefully be changed in a libification effort, to return NULL when
@@ -865,7 +876,7 @@ struct child_process *git_connect(int fd[2], const char *url,
 				  const char *prog, int flags)
 {
 	char *hostandport, *path;
-	struct child_process *conn = &no_fork;
+	struct child_process *conn;
 	enum protocol protocol;
 
 	/* Without this we cannot rely on waitpid() to tell
@@ -901,7 +912,7 @@ struct child_process *git_connect(int fd[2], const char *url,
 		if (git_use_proxy(hostandport))
 			conn = git_proxy_connect(fd, hostandport);
 		else
-			git_tcp_connect(fd, hostandport, flags);
+			conn = git_tcp_connect(fd, hostandport, flags);
 		/*
 		 * Separate original protocol components prog and path
 		 * from extended host header with a NUL byte.
@@ -1041,11 +1052,6 @@ struct child_process *git_connect(int fd[2], const char *url,
 	return conn;
 }
 
-int git_connection_is_socket(struct child_process *conn)
-{
-	return conn == &no_fork;
-}
-
 int finish_connect(struct child_process *conn)
 {
 	int code;
-- 
2.15.0.448.gf294e3d99a
Previous: Stefan BellerNext: Jonathan Nieder
Message 7 of 27 in “Coping with unrecognized ssh wrapper scripts in GIT_SSH”
  1. 0/8 Coping with unrecognized ssh wrapper scripts in GIT_SSHJonathan Nieder, Nov 20, 2017
  2. 1/8 ssh test: make copy_ssh_wrapper_as clean up after itselfJonathan Nieder, Nov 20, 2017
  3. Brandon WilliamsNov 20, 2017
  4. Junio C HamanoNov 21, 2017
  5. 1/8 ssh test: make copy_ssh_wrapper_as clean up after itselfJonathan Nieder, Nov 21, 2017
  6. Stefan BellerNov 21, 2017
  7. 2/8 connect: move no_fork fallback to git_tcp_connectJonathan Nieder, Nov 20, 2017
  8. 3/8 connect: split git:// setup into a separate functionJonathan Nieder, Nov 20, 2017
  9. Brandon WilliamsNov 20, 2017
  10. Jonathan NiederNov 20, 2017
  11. Brandon WilliamsNov 20, 2017
  12. 4/8 connect: split ssh command line options into separate functionJonathan Nieder, Nov 20, 2017
  13. Brandon WilliamsNov 20, 2017
  14. Jonathan NiederNov 20, 2017
  15. Brandon WilliamsNov 20, 2017
  16. 4/8 connect: split ssh command line options into separate functionJonathan Nieder, Nov 20, 2017
  17. 5/8 connect: split ssh option computation to its own functionJonathan Nieder, Nov 20, 2017
  18. Junio C HamanoNov 21, 2017
  19. 6/8 ssh: 'auto' variant to select between 'ssh' and 'simple'Jonathan Nieder, Nov 20, 2017
  20. Brandon WilliamsNov 20, 2017
  21. Junio C HamanoNov 21, 2017
  22. Jonathan NiederNov 21, 2017
  23. 7/8 ssh: 'simple' variant does not support -4/-6Jonathan Nieder, Nov 20, 2017
  24. 8/8 ssh: 'simple' variant does not support --portJonathan Nieder, Nov 20, 2017
  25. Brandon WilliamsNov 20, 2017
  26. Stefan BellerNov 22, 2017
  27. Junio C HamanoNov 22, 2017

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