Integrate diffstat with diff

This creates a generic diffstat function in ui-diff, which then is
invoked from cgit_print_diff with the result that both commit and diff-
view gets a diffstat.

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

1 files changed, 145 insertions, 0 deletions

diff --git a/ui-diff.c b/ui-diff.c
index 2a22009..625b5fd 100644
--- a/ui-diff.c
+++ b/ui-diff.c
@@ -13,6 +13,149 @@
 unsigned char old_rev_sha1[20];
 unsigned char new_rev_sha1[20];
 
+static int files, slots;
+static int total_adds, total_rems, max_changes;
+static int lines_added, lines_removed;
+static char *curr_rev;
+
+static struct fileinfo {
+        char status;
+        unsigned char old_sha1[20];
+        unsigned char new_sha1[20];
+        unsigned short old_mode;
+        unsigned short new_mode;
+        char *old_path;
+        char *new_path;
+        unsigned int added;
+        unsigned int removed;
+} *items;
+
+
+static void print_fileinfo(struct fileinfo *info)
+{
+        char *class;
+
+        switch (info->status) {
+        case DIFF_STATUS_ADDED:
+                class = "add";
+                break;
+        case DIFF_STATUS_COPIED:
+                class = "cpy";
+                break;
+        case DIFF_STATUS_DELETED:
+                class = "del";
+                break;
+        case DIFF_STATUS_MODIFIED:
+                class = "upd";
+                break;
+        case DIFF_STATUS_RENAMED:
+                class = "mov";
+                break;
+        case DIFF_STATUS_TYPE_CHANGED:
+                class = "typ";
+                break;
+        case DIFF_STATUS_UNKNOWN:
+                class = "unk";
+                break;
+        case DIFF_STATUS_UNMERGED:
+                class = "stg";
+                break;
+        default:
+                die("bug: unhandled diff status %c", info->status);
+        }
+
+        html("<tr>");
+        htmlf("<td class='mode'>");
+        if (is_null_sha1(info->new_sha1)) {
+                cgit_print_filemode(info->old_mode);
+        } else {
+                cgit_print_filemode(info->new_mode);
+        }
+
+        if (info->old_mode != info->new_mode &&
+            !is_null_sha1(info->old_sha1) &&
+            !is_null_sha1(info->new_sha1)) {
+                html("<span class='modechange'>[");
+                cgit_print_filemode(info->old_mode);
+                html("]</span>");
+        }
+        htmlf("</td><td class='%s'>", class);
+        cgit_diff_link(info->new_path, NULL, NULL, ctx.qry.head, curr_rev,
+                       NULL, info->new_path);
+        if (info->status == DIFF_STATUS_COPIED || info->status == DIFF_STATUS_RENAMED)
+                htmlf(" (%s from %s)",
+                      info->status == DIFF_STATUS_COPIED ? "copied" : "renamed",
+                      info->old_path);
+        html("</td><td class='right'>");
+        htmlf("%d", info->added + info->removed);
+        html("</td><td class='graph'>");
+        htmlf("<table summary='file diffstat' width='%d%%'><tr>", (max_changes > 100 ? 100 : max_changes));
+        htmlf("<td class='add' style='width: %.1f%%;'/>",
+              info->added * 100.0 / max_changes);
+        htmlf("<td class='rem' style='width: %.1f%%;'/>",
+              info->removed * 100.0 / max_changes);
+        htmlf("<td class='none' style='width: %.1f%%;'/>",
+              (max_changes - info->removed - info->added) * 100.0 / max_changes);
+        html("</tr></table></td></tr>\n");
+}
+
+static void count_diff_lines(char *line, int len)
+{
+        if (line && (len > 0)) {
+                if (line[0] == '+')
+                        lines_added++;
+                else if (line[0] == '-')
+                        lines_removed++;
+        }
+}
+
+static void inspect_filepair(struct diff_filepair *pair)
+{
+        files++;
+        lines_added = 0;
+        lines_removed = 0;
+        cgit_diff_files(pair->one->sha1, pair->two->sha1, count_diff_lines);
+        if (files >= slots) {
+                if (slots == 0)
+                        slots = 4;
+                else
+                        slots = slots * 2;
+                items = xrealloc(items, slots * sizeof(struct fileinfo));
+        }
+        items[files-1].status = pair->status;
+        hashcpy(items[files-1].old_sha1, pair->one->sha1);
+        hashcpy(items[files-1].new_sha1, pair->two->sha1);
+        items[files-1].old_mode = pair->one->mode;
+        items[files-1].new_mode = pair->two->mode;
+        items[files-1].old_path = xstrdup(pair->one->path);
+        items[files-1].new_path = xstrdup(pair->two->path);
+        items[files-1].added = lines_added;
+        items[files-1].removed = lines_removed;
+        if (lines_added + lines_removed > max_changes)
+                max_changes = lines_added + lines_removed;
+        total_adds += lines_added;
+        total_rems += lines_removed;
+}
+
+void cgit_print_diffstat(const unsigned char *old_sha1,
+                         const unsigned char *new_sha1)
+{
+        int i;
+
+        html("<div class='diffstat-header'>Diffstat</div>");
+        html("<table summary='diffstat' class='diffstat'>");
+        max_changes = 0;
+        cgit_diff_tree(old_sha1, new_sha1, inspect_filepair, NULL);
+        for(i = 0; i<files; i++)
+                print_fileinfo(&items[i]);
+        html("</table>");
+        html("<div class='diffstat-summary'>");
+        htmlf("%d files changed, %d insertions, %d deletions",
+              files, total_adds, total_rems);
+        html("</div>");
+}
+
+
 /*
  * print a single line returned from xdiff
  */
@@ -142,6 +285,8 @@ void cgit_print_diff(const char *new_rev, const char *old_rev, const char *prefi
                 if (!commit2 || parse_commit(commit2))
                         cgit_print_error(fmt("Bad commit: %s", sha1_to_hex(old_rev_sha1)));
         }
+        cgit_print_diffstat(old_rev_sha1, new_rev_sha1);
+
         html("<table summary='diff' class='diff'>");
         html("<tr><td>");
         cgit_diff_tree(old_rev_sha1, new_rev_sha1, filepair_cb, prefix);