5 files changed, 49 insertions, 12 deletions

diff --git a/source/cgit.c b/source/cgit.c
index 29b2131..8a7027c 100644
--- a/source/cgit.c
+++ b/source/cgit.c
@@ -201,6 +201,8 @@ static void config_cb(const char *name, const char *value)
 		ctx.cfg.enable_tree_linenumbers = atoi(value);
 	else if (!strcmp(name, "enable-tree-group-dirs"))
 		ctx.cfg.enable_tree_group_dirs = atoi(value);
+	else if (!strcmp(name, "enable-markdown"))
+		ctx.cfg.enable_markdown = atoi(value);
 	else if (!strcmp(name, "enable-git-config"))
 		ctx.cfg.enable_git_config = atoi(value);
 	else if (!strcmp(name, "enable-cache-list"))
@@ -394,6 +396,7 @@ static void prepare_context(void)
 	ctx.cfg.enable_http_clone = 1;
 	ctx.cfg.enable_index_owner = 1;
 	ctx.cfg.enable_tree_linenumbers = 1;
+	ctx.cfg.enable_markdown = 1;
 	ctx.cfg.enable_git_config = 0;
 	ctx.cfg.max_repo_count = 50;
 	ctx.cfg.max_commit_count = 50;
diff --git a/source/cgit.h b/source/cgit.h
index ab7b284..3cd0317 100644
--- a/source/cgit.h
+++ b/source/cgit.h
@@ -243,6 +243,7 @@ struct cgit_config {
 	int enable_html_serving;
 	int enable_tree_linenumbers;
 	int enable_tree_group_dirs;
+	int enable_markdown;
 	int enable_git_config;
 	int enable_cache_list;
 	int local_time;
diff --git a/source/ui-blob.c b/source/ui-blob.c
index bc91656..7720a28 100644
--- a/source/ui-blob.c
+++ b/source/ui-blob.c
@@ -67,7 +67,7 @@ done:
 	return walk_tree_ctx.found_path;
 }
 
-int cgit_print_file(char *path, const char *head, int file_only)
+int cgit_print_file(char *path, const char *head, int file_only, int html_escape)
 {
 	struct object_id oid;
 	enum object_type type;
@@ -106,7 +106,10 @@ int cgit_print_file(char *path, const char *head, int file_only)
 	if (!buf)
 		return -1;
 	buf[size] = '\0';
-	html_raw(buf, size);
+	if (html_escape)
+		html_txt(buf);
+	else
+		html_raw(buf, size);
 	free(buf);
 	return 0;
 }
diff --git a/source/ui-blob.h b/source/ui-blob.h
index 16847b2..efbc94e 100644
--- a/source/ui-blob.h
+++ b/source/ui-blob.h
@@ -2,7 +2,7 @@
 #define UI_BLOB_H
 
 extern int cgit_ref_path_exists(const char *path, const char *ref, int file_only);
-extern int cgit_print_file(char *path, const char *head, int file_only);
+extern int cgit_print_file(char *path, const char *head, int file_only, int html_escape);
 extern void cgit_print_blob(const char *hex, char *path, const char *head, int file_only);
 
 #endif /* UI_BLOB_H */
diff --git a/source/ui-summary.c b/source/ui-summary.c
index 947812a..7e533e1 100644
--- a/source/ui-summary.c
+++ b/source/ui-summary.c
@@ -99,6 +99,17 @@ static char* append_readme_path(const char *filename, const char *ref, const cha
 	return full_path;
 }
 
+static int readme_is_markdown(const char *filename)
+{
+	const char *ext = strrchr(filename, '.');
+
+	if (!ext || !ext[1])
+		return 0;
+	ext++;
+	return !strcasecmp(ext, "md") || !strcasecmp(ext, "markdown") ||
+	       !strcasecmp(ext, "mkd") || !strcasecmp(ext, "mdown");
+}
+
 void cgit_print_repo_readme(const char *path)
 {
 	char *filename, *ref, *mimetype;
@@ -128,16 +139,35 @@ void cgit_print_repo_readme(const char *path)
 			goto done;
 	}
 
-	/* Print the calculated readme, either from the git repo or from the
-	 * filesystem, while applying the about-filter.
-	 */
 	html("<div id='summary'>");
-	cgit_open_filter(ctx.repo->about_filter, filename);
-	if (ref)
-		cgit_print_file(filename, ref, 1);
-	else
-		html_include(filename);
-	cgit_close_filter(ctx.repo->about_filter);
+	if (!ctx.repo->about_filter && ctx.cfg.enable_markdown &&
+	    readme_is_markdown(filename)) {
+		/* No about-filter is set, so hand the markdown source to the
+		 * built-in client-side renderer in cgit.js. The source is
+		 * escaped here and rendered in the browser, and it degrades to
+		 * readable plain text when scripting is off.
+		 */
+		html("<div class='markdown' data-markdown>");
+		if (ref) {
+			cgit_print_file(filename, ref, 1, 1);
+		} else {
+			struct strbuf sb = STRBUF_INIT;
+			if (strbuf_read_file(&sb, filename, 0) >= 0)
+				html_txt(sb.buf);
+			strbuf_release(&sb);
+		}
+		html("</div>");
+	} else {
+		/* Otherwise print the readme through the about-filter, or raw
+		 * when none is configured.
+		 */
+		cgit_open_filter(ctx.repo->about_filter, filename);
+		if (ref)
+			cgit_print_file(filename, ref, 1, 0);
+		else
+			html_include(filename);
+		cgit_close_filter(ctx.repo->about_filter);
+	}
 
 	html("</div>");
 	if (free_filename)