log: allow users to follow a file

[ps-cgit] / ui-diff.c

diff --git a/ui-diff.c b/ui-diff.c
index 1cf2ce0c8e32b1a600b855c0d9951297d2fdcafa..caebd5d9eea61053cdcf8c85672acd506a9e0b52 100644 (file)
--- a/ui-diff.c
+++ b/ui-diff.c
@@ -36,6 +36,7 @@ static struct fileinfo {
 
 static int use_ssdiff = 0;
 static struct diff_filepair *current_filepair;
+static const char *current_prefix;
 
 struct diff_filespec *cgit_get_current_old_file(void)
 {
@@ -132,11 +133,30 @@ static void count_diff_lines(char *line, int len)
        }
 }
 
+static int show_filepair(struct diff_filepair *pair)
+{
+       /* Always show if we have no limiting prefix. */
+       if (!current_prefix)
+               return 1;
+
+       /* Show if either path in the pair begins with the prefix. */
+       if (starts_with(pair->one->path, current_prefix) ||
+           starts_with(pair->two->path, current_prefix))
+               return 1;
+
+       /* Otherwise we don't want to show this filepair. */
+       return 0;
+}
+
 static void inspect_filepair(struct diff_filepair *pair)
 {
        int binary = 0;
        unsigned long old_size = 0;
        unsigned long new_size = 0;
+
+       if (!show_filepair(pair))
+               return;
+
        files++;
        lines_added = 0;
        lines_removed = 0;
@@ -279,6 +299,9 @@ static void filepair_cb(struct diff_filepair *pair)
        int binary = 0;
        linediff_fn print_line_fn = print_line;
 
+       if (!show_filepair(pair))
+               return;
+
        current_filepair = pair;
        if (use_ssdiff) {
                cgit_ssdiff_header_begin();
@@ -365,6 +388,18 @@ void cgit_print_diff(const char *new_rev, const char *old_rev,
        const unsigned char *old_tree_sha1, *new_tree_sha1;
        diff_type difftype;
 
+       /*
+        * If "follow" is set then the diff machinery needs to examine the
+        * entire commit to detect renames so we must limit the paths in our
+        * own callbacks and not pass the prefix to the diff machinery.
+        */
+       if (ctx.qry.follow && ctx.cfg.enable_follow_links) {
+               current_prefix = prefix;
+               prefix = "";
+       } else {
+               current_prefix = NULL;
+       }
+
        if (!new_rev)
                new_rev = ctx.qry.head;
        if (get_sha1(new_rev, new_rev_sha1)) {