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);