grep doc: add --break / --heading / -W to synopsis

[git.git] / unix-socket.c

diff --git a/unix-socket.c b/unix-socket.c
index 84b15099f2fbf89dedf5241a6176b39abd4b1723..01f119f9700791ddc59a81cdc80fd365e678622a 100644 (file)
--- a/unix-socket.c
+++ b/unix-socket.c
@@ -9,48 +9,114 @@ static int unix_stream_socket(void)
        return fd;
 }
 
-static void unix_sockaddr_init(struct sockaddr_un *sa, const char *path)
+static int chdir_len(const char *orig, int len)
+{
+       char *path = xmemdupz(orig, len);
+       int r = chdir(path);
+       free(path);
+       return r;
+}
+
+struct unix_sockaddr_context {
+       char orig_dir[PATH_MAX];
+};
+
+static void unix_sockaddr_cleanup(struct unix_sockaddr_context *ctx)
+{
+       if (!ctx->orig_dir[0])
+               return;
+       /*
+        * If we fail, we can't just return an error, since we have
+        * moved the cwd of the whole process, which could confuse calling
+        * code.  We are better off to just die.
+        */
+       if (chdir(ctx->orig_dir) < 0)
+               die("unable to restore original working directory");
+}
+
+static int unix_sockaddr_init(struct sockaddr_un *sa, const char *path,
+                             struct unix_sockaddr_context *ctx)
 {
        int size = strlen(path) + 1;
-       if (size > sizeof(sa->sun_path))
-               die("socket path is too long to fit in sockaddr");
+
+       ctx->orig_dir[0] = '\0';
+       if (size > sizeof(sa->sun_path)) {
+               const char *slash = find_last_dir_sep(path);
+               const char *dir;
+
+               if (!slash) {
+                       errno = ENAMETOOLONG;
+                       return -1;
+               }
+
+               dir = path;
+               path = slash + 1;
+               size = strlen(path) + 1;
+               if (size > sizeof(sa->sun_path)) {
+                       errno = ENAMETOOLONG;
+                       return -1;
+               }
+
+               if (!getcwd(ctx->orig_dir, sizeof(ctx->orig_dir))) {
+                       errno = ENAMETOOLONG;
+                       return -1;
+               }
+               if (chdir_len(dir, slash - dir) < 0)
+                       return -1;
+       }
+
        memset(sa, 0, sizeof(*sa));
        sa->sun_family = AF_UNIX;
        memcpy(sa->sun_path, path, size);
+       return 0;
 }
 
 int unix_stream_connect(const char *path)
 {
-       int fd;
+       int fd, saved_errno;
        struct sockaddr_un sa;
+       struct unix_sockaddr_context ctx;
 
-       unix_sockaddr_init(&sa, path);
-       fd = unix_stream_socket();
-       if (connect(fd, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
-               close(fd);
+       if (unix_sockaddr_init(&sa, path, &ctx) < 0)
                return -1;
-       }
+       fd = unix_stream_socket();
+       if (connect(fd, (struct sockaddr *)&sa, sizeof(sa)) < 0)
+               goto fail;
+       unix_sockaddr_cleanup(&ctx);
        return fd;
+
+fail:
+       saved_errno = errno;
+       unix_sockaddr_cleanup(&ctx);
+       close(fd);
+       errno = saved_errno;
+       return -1;
 }
 
 int unix_stream_listen(const char *path)
 {
-       int fd;
+       int fd, saved_errno;
        struct sockaddr_un sa;
+       struct unix_sockaddr_context ctx;
 
-       unix_sockaddr_init(&sa, path);
+       if (unix_sockaddr_init(&sa, path, &ctx) < 0)
+               return -1;
        fd = unix_stream_socket();
 
        unlink(path);
-       if (bind(fd, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
-               close(fd);
-               return -1;
-       }
+       if (bind(fd, (struct sockaddr *)&sa, sizeof(sa)) < 0)
+               goto fail;
 
-       if (listen(fd, 5) < 0) {
-               close(fd);
-               return -1;
-       }
+       if (listen(fd, 5) < 0)
+               goto fail;
 
+       unix_sockaddr_cleanup(&ctx);
        return fd;
+
+fail:
+       saved_errno = errno;
+       unix_sockaddr_cleanup(&ctx);
+       close(fd);
+       errno = saved_errno;
+       return -1;
 }