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);
 }