ui-plain: more efficient walk_tree()

Git's read_tree_recursive() already filters out the objects by pathname,
so we only have to compare baselen to the expected.  That is, no string
matching is required.

Additionally, if the requested path is a directory, the old code would
walk through all of its immediate children.  This is not necessary, this
so we no longer do that.

Signed-off-by: Mark Lodato <lodatom@gmail.com>

1 files changed, 14 insertions, 6 deletions

diff --git a/ui-plain.c b/ui-plain.c
index 98e6908..8b0badd 100644
--- a/ui-plain.c
+++ b/ui-plain.c
@@ -1,92 +1,100 @@
 /* ui-plain.c: functions for output of plain blobs by path
  *
  * Copyright (C) 2008 Lars Hjemli
  *
  * Licensed under GNU General Public License v2
  *   (see COPYING for full license text)
  */
 
 #include "cgit.h"
 #include "html.h"
 #include "ui-shared.h"
 
-char *match_path;
+int match_baselen;
 int match;
 
 static void print_object(const unsigned char *sha1, const char *path)
 {
 	enum object_type type;
 	char *buf, *ext;
 	unsigned long size;
 	struct string_list_item *mime;
 
 	type = sha1_object_info(sha1, &size);
 	if (type == OBJ_BAD) {
 		html_status(404, "Not found", 0);
 		return;
 	}
 
 	buf = read_sha1_file(sha1, &type, &size);
 	if (!buf) {
 		html_status(404, "Not found", 0);
 		return;
 	}
 	ctx.page.mimetype = NULL;
 	ext = strrchr(path, '.');
 	if (ext && *(++ext)) {
 		mime = string_list_lookup(ext, &ctx.cfg.mimetypes);
 		if (mime)
 			ctx.page.mimetype = (char *)mime->util;
 	}
 	if (!ctx.page.mimetype) {
 		if (buffer_is_binary(buf, size))
 			ctx.page.mimetype = "application/octet-stream";
 		else
 			ctx.page.mimetype = "text/plain";
 	}
 	ctx.page.filename = fmt("%s", path);
 	ctx.page.size = size;
 	ctx.page.etag = sha1_to_hex(sha1);
 	cgit_print_http_headers(&ctx);
 	html_raw(buf, size);
 	match = 1;
 }
 
 static int walk_tree(const unsigned char *sha1, const char *base, int baselen,
 		     const char *pathname, unsigned mode, int stage,
 		     void *cbdata)
 {
-	if (S_ISDIR(mode))
+	if (baselen == match_baselen) {
+		if (S_ISREG(mode))
+			print_object(sha1, pathname);
+	}
+	else if (S_ISDIR(mode))
 		return READ_TREE_RECURSIVE;
 
-	if (S_ISREG(mode) && !strncmp(base, match_path, baselen) &&
-	    !strcmp(pathname, match_path + baselen))
-		print_object(sha1, pathname);
+	return 0;
+}
 
+static int basedir_len(const char *path)
+{
+	char *p = strrchr(path, '/');
+	if (p)
+		return p - path + 1;
 	return 0;
 }
 
 void cgit_print_plain(struct cgit_context *ctx)
 {
 	const char *rev = ctx->qry.sha1;
 	unsigned char sha1[20];
 	struct commit *commit;
 	const char *paths[] = {ctx->qry.path, NULL};
 
 	if (!rev)
 		rev = ctx->qry.head;
 
 	if (get_sha1(rev, sha1)) {
 		html_status(404, "Not found", 0);
 		return;
 	}
 	commit = lookup_commit_reference(sha1);
 	if (!commit || parse_commit(commit)) {
 		html_status(404, "Not found", 0);
 		return;
 	}
-	match_path = ctx->qry.path;
+	match_baselen = basedir_len(paths[0]);
 	read_tree_recursive(commit->tree, "", 0, 0, paths, walk_tree, NULL);
 	if (!match)
 		html_status(404, "Not found", 0);
 }