ui-shared: avoid the memrchr GNU extension

memrchr() is a GNU extension which glibc and musl provide but macOS does
not, so cgit_set_title_from_path() failed to compile there and the tree
could not be built on macOS at all.

Replace it with a small local helper. The search covers one path
component at a time, so there is nothing to gain from a libc version.

Signed-off-by: Saya Andy <saya.andy@posteo.com>

1 files changed, 12 insertions, 1 deletions

diff --git a/ui-shared.c b/ui-shared.c
index df52a9b..9f7625c 100644
--- a/ui-shared.c
+++ b/ui-shared.c
@@ -1247,6 +1247,17 @@ void cgit_print_snapshot_links(const struct cgit_repo *repo, const char *ref,
 	strbuf_release(&filename);
 }
 
+/* Locate the last '/' within the first len bytes of path, or NULL if
+ * there is none.  Avoids memrchr(), which is a GNU extension.
+ */
+static const char *find_last_slash(const char *path, size_t len)
+{
+	while (len > 0)
+		if (path[--len] == '/')
+			return path + len;
+	return NULL;
+}
+
 void cgit_set_title_from_path(const char *path)
 {
 	struct strbuf sb = STRBUF_INIT;
@@ -1255,7 +1266,7 @@ void cgit_set_title_from_path(const char *path)
 	if (!path)
 		return;
 
-	for (last_slash = path + strlen(path); (slash = memrchr(path, '/', last_slash - path)) != NULL; last_slash = slash) {
+	for (last_slash = path + strlen(path); (slash = find_last_slash(path, last_slash - path)) != NULL; last_slash = slash) {
 		strbuf_add(&sb, slash + 1, last_slash - slash - 1);
 		strbuf_addstr(&sb, " \xc2\xab ");
 	}