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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-09 13:34:27 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-09 13:34:27 +0000
commit4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f (patch)
tree47c1d492e9c956c1cd2b74dbd3b9d8b0db44dc4e /unix-socket.c
parentInitial commit. (diff)
downloadgit-4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f.tar.xz
git-4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f.zip
Adding upstream version 1:2.43.0.upstream/1%2.43.0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'unix-socket.c')
-rw-r--r--unix-socket.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/unix-socket.c b/unix-socket.c
new file mode 100644
index 0000000..79800d8
--- /dev/null
+++ b/unix-socket.c
@@ -0,0 +1,137 @@
+#include "git-compat-util.h"
+#include "strbuf.h"
+#include "unix-socket.h"
+
+#define DEFAULT_UNIX_STREAM_LISTEN_BACKLOG (5)
+
+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;
+};
+
+static void unix_sockaddr_cleanup(struct unix_sockaddr_context *ctx)
+{
+ if (!ctx->orig_dir)
+ 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");
+ free(ctx->orig_dir);
+}
+
+static int unix_sockaddr_init(struct sockaddr_un *sa, const char *path,
+ struct unix_sockaddr_context *ctx,
+ int disallow_chdir)
+{
+ int size = strlen(path) + 1;
+
+ ctx->orig_dir = NULL;
+ if (size > sizeof(sa->sun_path)) {
+ const char *slash;
+ const char *dir;
+ struct strbuf cwd = STRBUF_INIT;
+
+ if (disallow_chdir) {
+ errno = ENAMETOOLONG;
+ return -1;
+ }
+
+ slash = find_last_dir_sep(path);
+ 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 (strbuf_getcwd(&cwd))
+ return -1;
+ ctx->orig_dir = strbuf_detach(&cwd, NULL);
+ 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 disallow_chdir)
+{
+ int fd = -1, saved_errno;
+ struct sockaddr_un sa;
+ struct unix_sockaddr_context ctx;
+
+ if (unix_sockaddr_init(&sa, path, &ctx, disallow_chdir) < 0)
+ return -1;
+ fd = socket(AF_UNIX, SOCK_STREAM, 0);
+ if (fd < 0)
+ goto fail;
+
+ if (connect(fd, (struct sockaddr *)&sa, sizeof(sa)) < 0)
+ goto fail;
+ unix_sockaddr_cleanup(&ctx);
+ return fd;
+
+fail:
+ saved_errno = errno;
+ if (fd != -1)
+ close(fd);
+ unix_sockaddr_cleanup(&ctx);
+ errno = saved_errno;
+ return -1;
+}
+
+int unix_stream_listen(const char *path,
+ const struct unix_stream_listen_opts *opts)
+{
+ int fd = -1, saved_errno;
+ int backlog;
+ struct sockaddr_un sa;
+ struct unix_sockaddr_context ctx;
+
+ unlink(path);
+
+ if (unix_sockaddr_init(&sa, path, &ctx, opts->disallow_chdir) < 0)
+ return -1;
+ fd = socket(AF_UNIX, SOCK_STREAM, 0);
+ if (fd < 0)
+ goto fail;
+
+ if (bind(fd, (struct sockaddr *)&sa, sizeof(sa)) < 0)
+ goto fail;
+
+ backlog = opts->listen_backlog_size;
+ if (backlog <= 0)
+ backlog = DEFAULT_UNIX_STREAM_LISTEN_BACKLOG;
+ if (listen(fd, backlog) < 0)
+ goto fail;
+
+ unix_sockaddr_cleanup(&ctx);
+ return fd;
+
+fail:
+ saved_errno = errno;
+ if (fd != -1)
+ close(fd);
+ unix_sockaddr_cleanup(&ctx);
+ errno = saved_errno;
+ return -1;
+}