Add commitdiff between commit and each of it's parent

A link is added next to each parent of a commit, leading to the new
diff-functionality in ui-diff.c.

Also added support for a path-parameter to filelevel diffs accessed via the
diffstat.

Signed-off-by: Lars Hjemli <hjemli@gmail.com>

1 files changed, 41 insertions, 4 deletions

diff --git a/ui-diff.c b/ui-diff.c
index 96106af..10330d3 100644
--- a/ui-diff.c
+++ b/ui-diff.c
@@ -10,36 +10,73 @@
 
 
 /*
  * print a single line returned from xdiff
  */
 static void print_line(char *line, int len)
 {
         char *class = "ctx";
         char c = line[len-1];
 
         if (line[0] == '+')
                 class = "add";
         else if (line[0] == '-')
                 class = "del";
         else if (line[0] == '@')
                 class = "hunk";
 
         htmlf("<div class='%s'>", class);
         line[len-1] = '\0';
         html_txt(line);
         html("</div>");
         line[len-1] = c;
 }
 
-void cgit_print_diff(const char *old_hex, const char *new_hex)
+static void filepair_cb(struct diff_filepair *pair)
+{
+        html("<tr><th>");
+        html_txt(pair->two->path);
+        html("</th></tr>");
+        html("<tr><td>");
+        if (cgit_diff_files(pair->one->sha1, pair->two->sha1, print_line))
+                cgit_print_error("Error running diff");
+        html("</tr></td>");
+}
+
+void cgit_print_diff(const char *old_hex, const char *new_hex, char *path)
 {
         unsigned char sha1[20], sha2[20];
+        enum object_type type;
+        unsigned long size;
 
         get_sha1(old_hex, sha1);
         get_sha1(new_hex, sha2);
 
-        html("<table class='diff'><tr><td>");
-        if (cgit_diff_files(sha1, sha2, print_line))
-                cgit_print_error("Error running diff");
+        type = sha1_object_info(sha1, &size);
+        if (type == OBJ_BAD) {
+                type = sha1_object_info(sha2, &size);
+                if (type == OBJ_BAD) {
+                        cgit_print_error(fmt("Bad object names: %s, %s", old_hex, new_hex));
+                        return;
+                }
+        }
+
+        html("<table class='diff'>");
+        switch(type) {
+        case OBJ_BLOB:
+                if (path)
+                        htmlf("<tr><th>%s</th></tr>", path);
+                html("<tr><td>");
+                if (cgit_diff_files(sha1, sha2, print_line))
+                        cgit_print_error("Error running diff");
+                html("</tr></td>");
+                break;
+        case OBJ_TREE:
+                cgit_diff_tree(sha1, sha2, filepair_cb);
+                break;
+        default:
+                cgit_print_error(fmt("Unhandled object type: %s",
+                                     typename(type)));
+                break;
+        }
         html("</td></tr></table>");
 }