git: treat "git -C '<path>'" as a no-op when <path> is empty
[git.git] / unix-socket.c
blob19ed48be9902f321285bfbec3feaf8357fd5e9b9
1 #include "cache.h"
2 #include "unix-socket.h"
4 static int unix_stream_socket(void)
6 int fd = socket(AF_UNIX, SOCK_STREAM, 0);
7 if (fd < 0)
8 die_errno("unable to create socket");
9 return fd;
12 static int chdir_len(const char *orig, int len)
14 char *path = xmemdupz(orig, len);
15 int r = chdir(path);
16 free(path);
17 return r;
20 struct unix_sockaddr_context {
21 char *orig_dir;
24 static void unix_sockaddr_cleanup(struct unix_sockaddr_context *ctx)
26 if (!ctx->orig_dir)
27 return;
29 * If we fail, we can't just return an error, since we have
30 * moved the cwd of the whole process, which could confuse calling
31 * code. We are better off to just die.
33 if (chdir(ctx->orig_dir) < 0)
34 die("unable to restore original working directory");
35 free(ctx->orig_dir);
38 static int unix_sockaddr_init(struct sockaddr_un *sa, const char *path,
39 struct unix_sockaddr_context *ctx)
41 int size = strlen(path) + 1;
43 ctx->orig_dir = NULL;
44 if (size > sizeof(sa->sun_path)) {
45 const char *slash = find_last_dir_sep(path);
46 const char *dir;
47 struct strbuf cwd = STRBUF_INIT;
49 if (!slash) {
50 errno = ENAMETOOLONG;
51 return -1;
54 dir = path;
55 path = slash + 1;
56 size = strlen(path) + 1;
57 if (size > sizeof(sa->sun_path)) {
58 errno = ENAMETOOLONG;
59 return -1;
61 if (strbuf_getcwd(&cwd))
62 return -1;
63 ctx->orig_dir = strbuf_detach(&cwd, NULL);
64 if (chdir_len(dir, slash - dir) < 0)
65 return -1;
68 memset(sa, 0, sizeof(*sa));
69 sa->sun_family = AF_UNIX;
70 memcpy(sa->sun_path, path, size);
71 return 0;
74 int unix_stream_connect(const char *path)
76 int fd, saved_errno;
77 struct sockaddr_un sa;
78 struct unix_sockaddr_context ctx;
80 if (unix_sockaddr_init(&sa, path, &ctx) < 0)
81 return -1;
82 fd = unix_stream_socket();
83 if (connect(fd, (struct sockaddr *)&sa, sizeof(sa)) < 0)
84 goto fail;
85 unix_sockaddr_cleanup(&ctx);
86 return fd;
88 fail:
89 saved_errno = errno;
90 unix_sockaddr_cleanup(&ctx);
91 close(fd);
92 errno = saved_errno;
93 return -1;
96 int unix_stream_listen(const char *path)
98 int fd, saved_errno;
99 struct sockaddr_un sa;
100 struct unix_sockaddr_context ctx;
102 unlink(path);
104 if (unix_sockaddr_init(&sa, path, &ctx) < 0)
105 return -1;
106 fd = unix_stream_socket();
108 if (bind(fd, (struct sockaddr *)&sa, sizeof(sa)) < 0)
109 goto fail;
111 if (listen(fd, 5) < 0)
112 goto fail;
114 unix_sockaddr_cleanup(&ctx);
115 return fd;
117 fail:
118 saved_errno = errno;
119 unix_sockaddr_cleanup(&ctx);
120 close(fd);
121 errno = saved_errno;
122 return -1;