ssdiff: anchors for ssdiff

Emit anchors to the respective revisions in side-by-side diff view

Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>

4 files changed, 42 insertions, 10 deletions

diff --git a/cgit.css b/cgit.css
index a2a685b..3ed1989 100644
--- a/cgit.css
+++ b/cgit.css
@@ -86,385 +86,385 @@ table.tabs td a.active {
 	color: #000;
 	background-color: #ccc;
 }
 
 table.tabs td.form {
 	text-align: right;
 }
 
 table.tabs td.form form {
 	padding-bottom: 2px;
 	font-size: 90%;
 	white-space: nowrap;
 }
 
 table.tabs td.form input,
 table.tabs td.form select {
 	font-size: 90%;
 }
 
 div.path {
 	margin: 0px;
 	padding: 5px 2em 2px 2em;
 	color: #000;
 	background-color: #eee;
 }
 
 div.content {
 	margin: 0px;
 	padding: 2em;
 	border-bottom: solid 3px #ccc;
 }
 
 
 table.list {
 	width: 100%;
 	border: none;
 	border-collapse: collapse;
 }
 
 table.list tr {
 	background: white;
 }
 
 table.list tr.logheader {
 	background: #eee;
 }
 
 table.list tr:hover {
 	background: #eee;
 }
 
 table.list tr.nohover:hover {
 	background: white;
 }
 
 table.list th {
 	font-weight: bold;
 	/* color: #888;
 	border-top: dashed 1px #888;
 	border-bottom: dashed 1px #888;
 	*/
 	padding: 0.1em 0.5em 0.05em 0.5em;
 	vertical-align: baseline;
 }
 
 table.list td {
 	border: none;
 	padding: 0.1em 0.5em 0.1em 0.5em;
 }
 
 table.list td.logsubject {
 	font-family: monospace;
 	font-weight: bold;
 }
 
 table.list td.logmsg {
 	font-family: monospace;
 	white-space: pre;
 	padding: 1em 0.5em 2em 0.5em;
 }
 
 table.list td.lognotes-label {
 	text-align:right;
 	vertical-align:top;
 }
 
 table.list td.lognotes {
 	font-family: monospace;
 	white-space: pre;
 	padding: 0em 0.5em 2em 0.5em;
 }
 
 table.list td a {
 	color: black;
 }
 
 table.list td a.ls-dir {
 	font-weight: bold;
 	color: #00f;
 }
 
 table.list td a:hover {
 	color: #00f;
 }
 
 img {
 	border: none;
 }
 
 input#switch-btn {
 	margin: 2px 0px 0px 0px;
 }
 
 td#sidebar input.txt {
 	width: 100%;
 	margin: 2px 0px 0px 0px;
 }
 
 table#grid {
 	margin: 0px;
 }
 
 td#content {
 	vertical-align: top;
 	padding: 1em 2em 1em 1em;
 	border: none;
 }
 
 div#summary {
 	vertical-align: top;
 	margin-bottom: 1em;
 }
 
 table#downloads {
 	float: right;
 	border-collapse: collapse;
 	border: solid 1px #777;
 	margin-left: 0.5em;
 	margin-bottom: 0.5em;
 }
 
 table#downloads th {
 	background-color: #ccc;
 }
 
 div#blob {
 	border: solid 1px black;
 }
 
 div.error {
 	color: red;
 	font-weight: bold;
 	margin: 1em 2em;
 }
 
 a.ls-blob, a.ls-dir, a.ls-mod {
 	font-family: monospace;
 }
 
 td.ls-size {
 	text-align: right;
 	font-family: monospace;
 	width: 10em;
 }
 
 td.ls-mode {
 	font-family: monospace;
 	width: 10em;
 }
 
 table.blob {
 	margin-top: 0.5em;
 	border-top: solid 1px black;
 }
 
 table.blob td.lines {
 	margin: 0; padding: 0 0 0 0.5em;
 	vertical-align: top;
 	color: black;
 }
 
 table.blob td.linenumbers {
 	margin: 0; padding: 0 0.5em 0 0.5em;
 	vertical-align: top;
 	text-align: right;
 	border-right: 1px solid gray;
 }
 
 table.blob pre {
 	padding: 0; margin: 0;
 }
 
-table.blob a.no {
+table.blob a.no, table.ssdiff a.no {
 	color: gray;
 	text-align: right;
 	text-decoration: none;
 }
 
 table.blob a.no a:hover {
 	color: black;
 }
 
 table.bin-blob {
 	margin-top: 0.5em;
 	border: solid 1px black;
 }
 
 table.bin-blob th {
 	font-family: monospace;
 	white-space: pre;
 	border: solid 1px #777;
 	padding: 0.5em 1em;
 }
 
 table.bin-blob td {
 	font-family: monospace;
 	white-space: pre;
 	border-left: solid 1px #777;
 	padding: 0em 1em;
 }
 
 table.nowrap td {
 	white-space: nowrap;
 }
 
 table.commit-info {
 	border-collapse: collapse;
 	margin-top: 1.5em;
 }
 
 table.commit-info th {
 	text-align: left;
 	font-weight: normal;
 	padding: 0.1em 1em 0.1em 0.1em;
 	vertical-align: top;
 }
 
 table.commit-info td {
 	font-weight: normal;
 	padding: 0.1em 1em 0.1em 0.1em;
 }
 
 div.commit-subject {
 	font-weight: bold;
 	font-size: 125%;
 	margin: 1.5em 0em 0.5em 0em;
 	padding: 0em;
 }
 
 div.commit-msg {
 	white-space: pre;
 	font-family: monospace;
 }
 
 div.notes-header {
 	font-weight: bold;
 	padding-top: 1.5em;
 }
 
 div.notes {
 	white-space: pre;
 	font-family: monospace;
 	border: solid 1px #ee9;
 	background-color: #ffd;
 	padding: 0.3em 2em 0.3em 1em;
 	float: left;
 }
 
 div.notes-footer {
 	clear: left;
 }
 
 div.diffstat-header {
 	font-weight: bold;
 	padding-top: 1.5em;
 }
 
 table.diffstat {
 	border-collapse: collapse;
 	border: solid 1px #aaa;
 	background-color: #eee;
 }
 
 table.diffstat th {
 	font-weight: normal;
 	text-align: left;
 	text-decoration: underline;
 	padding: 0.1em 1em 0.1em 0.1em;
 	font-size: 100%;
 }
 
 table.diffstat td {
 	padding: 0.2em 0.2em 0.1em 0.1em;
 	font-size: 100%;
 	border: none;
 }
 
 table.diffstat td.mode {
 	white-space: nowrap;
 }
 
 table.diffstat td span.modechange {
 	padding-left: 1em;
 	color: red;
 }
 
 table.diffstat td.add a {
 	color: green;
 }
 
 table.diffstat td.del a {
 	color: red;
 }
 
 table.diffstat td.upd a {
 	color: blue;
 }
 
 table.diffstat td.graph {
 	width: 500px;
 	vertical-align: middle;
 }
 
 table.diffstat td.graph table {
 	border: none;
 }
 
 table.diffstat td.graph td {
 	padding: 0px;
 	border: 0px;
 	height: 7pt;
 }
 
 table.diffstat td.graph td.add {
 	background-color: #5c5;
 }
 
 table.diffstat td.graph td.rem {
 	background-color: #c55;
 }
 
 div.diffstat-summary {
 	color: #888;
 	padding-top: 0.5em;
 }
 
 table.diff {
 	width: 100%;
 }
 
 table.diff td {
 	font-family: monospace;
 	white-space: pre;
 }
 
 table.diff td div.head {
 	font-weight: bold;
 	margin-top: 1em;
 	color: black;
 }
 
 table.diff td div.hunk {
 	color: #009;
 }
 
 table.diff td div.add {
 	color: green;
 }
 
 table.diff td div.del {
 	color: red;
 }
 
 .sha1 {
 	font-family: monospace;
 	font-size: 90%;
 }
 
 .left {
 	text-align: left;
 }
 
 .right {
 	text-align: right;
 }
diff --git a/ui-diff.c b/ui-diff.c
index 7ff7e46..a53425d 100644
--- a/ui-diff.c
+++ b/ui-diff.c
@@ -1,371 +1,383 @@
 /* ui-diff.c: show diff between two blobs
  *
  * Copyright (C) 2006 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"
 #include "ui-ssdiff.h"
 
 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 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;
 	unsigned long old_size;
 	unsigned long new_size;
 	int binary:1;
 } *items;
 
 static int use_ssdiff = 0;
+static struct diff_filepair *current_filepair;
+
+struct diff_filespec *cgit_get_current_old_file(void)
+{
+	return current_filepair->one;
+}
+
+struct diff_filespec *cgit_get_current_new_file(void)
+{
+	return current_filepair->two;
+}
 
 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, ctx.qry.sha1,
 		       ctx.qry.sha2, info->new_path, 0);
 	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'>");
 	if (info->binary) {
 		htmlf("bin</td><td class='graph'>%ld -> %ld bytes",
 		      info->old_size, info->new_size);
 		return;
 	}
 	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)
 {
 	int binary = 0;
 	unsigned long old_size = 0;
 	unsigned long new_size = 0;
 	files++;
 	lines_added = 0;
 	lines_removed = 0;
 	cgit_diff_files(pair->one->sha1, pair->two->sha1, &old_size, &new_size,
 			&binary, 0, ctx.qry.ignorews, 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;
 	items[files-1].old_size = old_size;
 	items[files-1].new_size = new_size;
 	items[files-1].binary = binary;
 	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, const char *prefix)
 {
 	int i, save_context = ctx.qry.context;
 
 	html("<div class='diffstat-header'>");
 	cgit_diff_link("Diffstat", NULL, NULL, ctx.qry.head, ctx.qry.sha1,
 		       ctx.qry.sha2, NULL, 0);
 	if (prefix)
 		htmlf(" (limited to '%s')", prefix);
 	html(" (");
 	ctx.qry.context = (save_context > 0 ? save_context : 3) << 1;
 	cgit_self_link("more", NULL, NULL, &ctx);
 	html("/");
 	ctx.qry.context = (save_context > 3 ? save_context : 3) >> 1;
 	cgit_self_link("less", NULL, NULL, &ctx);
 	ctx.qry.context = save_context;
 	html(" context)");
 	html(" (");
 	ctx.qry.ignorews = (ctx.qry.ignorews + 1) % 2;
 	cgit_self_link(ctx.qry.ignorews ? "ignore" : "show", NULL, NULL, &ctx);
 	ctx.qry.ignorews = (ctx.qry.ignorews + 1) % 2;
 	html(" whitespace changes)");
 	html("</div>");
 	html("<table summary='diffstat' class='diffstat'>");
 	max_changes = 0;
 	cgit_diff_tree(old_sha1, new_sha1, inspect_filepair, prefix,
 		       ctx.qry.ignorews);
 	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
  */
 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;
 }
 
 static void header(unsigned char *sha1, char *path1, int mode1,
 		   unsigned char *sha2, char *path2, int mode2)
 {
 	char *abbrev1, *abbrev2;
 	int subproject;
 
 	subproject = (S_ISGITLINK(mode1) || S_ISGITLINK(mode2));
 	html("<div class='head'>");
 	html("diff --git a/");
 	html_txt(path1);
 	html(" b/");
 	html_txt(path2);
 
 	if (is_null_sha1(sha1))
 		path1 = "dev/null";
 	if (is_null_sha1(sha2))
 		path2 = "dev/null";
 
 	if (mode1 == 0)
 		htmlf("<br/>new file mode %.6o", mode2);
 
 	if (mode2 == 0)
 		htmlf("<br/>deleted file mode %.6o", mode1);
 
 	if (!subproject) {
 		abbrev1 = xstrdup(find_unique_abbrev(sha1, DEFAULT_ABBREV));
 		abbrev2 = xstrdup(find_unique_abbrev(sha2, DEFAULT_ABBREV));
 		htmlf("<br/>index %s..%s", abbrev1, abbrev2);
 		free(abbrev1);
 		free(abbrev2);
 		if (mode1 != 0 && mode2 != 0) {
 			htmlf(" %.6o", mode1);
 			if (mode2 != mode1)
 				htmlf("..%.6o", mode2);
 		}
 		html("<br/>--- a/");
 		if (mode1 != 0)
 			cgit_tree_link(path1, NULL, NULL, ctx.qry.head,
 				       sha1_to_hex(old_rev_sha1), path1);
 		else
 			html_txt(path1);
 		html("<br/>+++ b/");
 		if (mode2 != 0)
 			cgit_tree_link(path2, NULL, NULL, ctx.qry.head,
 				       sha1_to_hex(new_rev_sha1), path2);
 		else
 			html_txt(path2);
 	}
 	html("</div>");
 }
 
 static void print_ssdiff_link()
 {
 	if (!strcmp(ctx.qry.page, "diff")) {
 		if (use_ssdiff)
 			cgit_diff_link("Unidiff", NULL, NULL, ctx.qry.head,
 				       ctx.qry.sha1, ctx.qry.sha2, ctx.qry.path, 1);
 		else
 			cgit_diff_link("Side-by-side diff", NULL, NULL,
 				       ctx.qry.head, ctx.qry.sha1,
 				       ctx.qry.sha2, ctx.qry.path, 1);
 	}
 }
 
 static void filepair_cb(struct diff_filepair *pair)
 {
 	unsigned long old_size = 0;
 	unsigned long new_size = 0;
 	int binary = 0;
 	linediff_fn print_line_fn = print_line;
 
+	current_filepair = pair;
 	if (use_ssdiff) {
 		cgit_ssdiff_header_begin();
 		print_line_fn = cgit_ssdiff_line_cb;
 	}
 	header(pair->one->sha1, pair->one->path, pair->one->mode,
 	       pair->two->sha1, pair->two->path, pair->two->mode);
 	if (use_ssdiff)
 		cgit_ssdiff_header_end();
 	if (S_ISGITLINK(pair->one->mode) || S_ISGITLINK(pair->two->mode)) {
 		if (S_ISGITLINK(pair->one->mode))
 			print_line_fn(fmt("-Subproject %s", sha1_to_hex(pair->one->sha1)), 52);
 		if (S_ISGITLINK(pair->two->mode))
 			print_line_fn(fmt("+Subproject %s", sha1_to_hex(pair->two->sha1)), 52);
 		if (use_ssdiff)
 			cgit_ssdiff_footer();
 		return;
 	}
 	if (cgit_diff_files(pair->one->sha1, pair->two->sha1, &old_size,
 			    &new_size, &binary, ctx.qry.context,
 			    ctx.qry.ignorews, print_line_fn))
 		cgit_print_error("Error running diff");
 	if (binary) {
 		if (use_ssdiff)
 			html("<tr><td colspan='4'>Binary files differ</td></tr>");
 		else
 			html("Binary files differ");
 	}
 	if (use_ssdiff)
 		cgit_ssdiff_footer();
 }
 
 void cgit_print_diff(const char *new_rev, const char *old_rev, const char *prefix)
 {
 	enum object_type type;
 	unsigned long size;
 	struct commit *commit, *commit2;
 
 	if (!new_rev)
 		new_rev = ctx.qry.head;
 	get_sha1(new_rev, new_rev_sha1);
 	type = sha1_object_info(new_rev_sha1, &size);
 	if (type == OBJ_BAD) {
 		cgit_print_error(fmt("Bad object name: %s", new_rev));
 		return;
 	}
 	commit = lookup_commit_reference(new_rev_sha1);
 	if (!commit || parse_commit(commit))
 		cgit_print_error(fmt("Bad commit: %s", sha1_to_hex(new_rev_sha1)));
 
 	if (old_rev)
 		get_sha1(old_rev, old_rev_sha1);
 	else if (commit->parents && commit->parents->item)
 		hashcpy(old_rev_sha1, commit->parents->item->object.sha1);
 	else
 		hashclr(old_rev_sha1);
 
 	if (!is_null_sha1(old_rev_sha1)) {
 		type = sha1_object_info(old_rev_sha1, &size);
 		if (type == OBJ_BAD) {
 			cgit_print_error(fmt("Bad object name: %s", sha1_to_hex(old_rev_sha1)));
 			return;
 		}
 		commit2 = lookup_commit_reference(old_rev_sha1);
 		if (!commit2 || parse_commit(commit2))
 			cgit_print_error(fmt("Bad commit: %s", sha1_to_hex(old_rev_sha1)));
 	}
 
 	if ((ctx.qry.ssdiff && !ctx.cfg.ssdiff) || (!ctx.qry.ssdiff && ctx.cfg.ssdiff))
 		use_ssdiff = 1;
 
 	print_ssdiff_link();
 	cgit_print_diffstat(old_rev_sha1, new_rev_sha1, prefix);
 
 	if (use_ssdiff) {
 		html("<table summary='ssdiff' class='ssdiff'>");
 	} else {
 		html("<table summary='diff' class='diff'>");
 		html("<tr><td>");
 	}
 	cgit_diff_tree(old_rev_sha1, new_rev_sha1, filepair_cb, prefix,
 		       ctx.qry.ignorews);
 	if (!use_ssdiff)
 		html("</td></tr>");
 	html("</table>");
 }
diff --git a/ui-diff.h b/ui-diff.h
index 70b2926..12d0c62 100644
--- a/ui-diff.h
+++ b/ui-diff.h
@@ -1,10 +1,16 @@
 #ifndef UI_DIFF_H
 #define UI_DIFF_H
 
 extern void cgit_print_diffstat(const unsigned char *old_sha1,
 				const unsigned char *new_sha1);
 
 extern void cgit_print_diff(const char *new_hex, const char *old_hex,
 			    const char *prefix);
 
+extern struct diff_filespec *cgit_get_current_old_file(void);
+extern struct diff_filespec *cgit_get_current_new_file(void);
+
+extern unsigned char old_rev_sha1[20];
+extern unsigned char new_rev_sha1[20];
+
 #endif /* UI_DIFF_H */
diff --git a/ui-ssdiff.c b/ui-ssdiff.c
index 408e620..2481585 100644
--- a/ui-ssdiff.c
+++ b/ui-ssdiff.c
@@ -1,369 +1,383 @@
 #include "cgit.h"
 #include "html.h"
 #include "ui-shared.h"
+#include "ui-diff.h"
 
 extern int use_ssdiff;
 
 static int current_old_line, current_new_line;
 
 struct deferred_lines {
 	int line_no;
 	char *line;
 	struct deferred_lines *next;
 };
 
 static struct deferred_lines *deferred_old, *deferred_old_last;
 static struct deferred_lines *deferred_new, *deferred_new_last;
 
 static char *longest_common_subsequence(char *A, char *B)
 {
 	int i, j, ri;
 	int m = strlen(A);
 	int n = strlen(B);
 	int L[m + 1][n + 1];
 	int tmp1, tmp2;
 	int lcs_length;
 	char *result;
 
 	for (i = m; i >= 0; i--) {
 		for (j = n; j >= 0; j--) {
 			if (A[i] == '\0' || B[j] == '\0') {
 				L[i][j] = 0;
 			} else if (A[i] == B[j]) {
 				L[i][j] = 1 + L[i + 1][j + 1];
 			} else {
 				tmp1 = L[i + 1][j];
 				tmp2 = L[i][j + 1];
 				L[i][j] = (tmp1 > tmp2 ? tmp1 : tmp2);
 			}
 		}
 	}
 
 	lcs_length = L[0][0];
 	result = xmalloc(lcs_length + 2);
 	memset(result, 0, sizeof(*result) * (lcs_length + 2));
 
 	ri = 0;
 	i = 0;
 	j = 0;
 	while (i < m && j < n) {
 		if (A[i] == B[j]) {
 			result[ri] = A[i];
 			ri += 1;
 			i += 1;
 			j += 1;
 		} else if (L[i + 1][j] >= L[i][j + 1]) {
 			i += 1;
 		} else {
 			j += 1;
 		}
 	}
 	return result;
 }
 
 static int line_from_hunk(char *line, char type)
 {
 	char *buf1, *buf2;
 	int len;
 
 	buf1 = strchr(line, type);
 	if (buf1 == NULL)
 		return 0;
 	buf1 += 1;
 	buf2 = strchr(buf1, ',');
 	if (buf2 == NULL)
 		return 0;
 	len = buf2 - buf1;
 	buf2 = xmalloc(len + 1);
 	strncpy(buf2, buf1, len);
 	buf2[len] = '\0';
 	int res = atoi(buf2);
 	free(buf2);
 	return res;
 }
 
 static char *replace_tabs(char *line)
 {
 	char *prev_buf = line;
 	char *cur_buf;
 	int linelen = strlen(line);
 	int n_tabs = 0;
 	int i;
 	char *result;
 	char *spaces = "        ";
 
 	if (linelen == 0) {
 		result = xmalloc(1);
 		result[0] = '\0';
 		return result;
 	}
 
 	for (i = 0; i < linelen; i++)
 		if (line[i] == '\t')
 			n_tabs += 1;
 	result = xmalloc(linelen + n_tabs * 8 + 1);
 	result[0] = '\0';
 
 	while (1) {
 		cur_buf = strchr(prev_buf, '\t');
 		if (!cur_buf) {
 			strcat(result, prev_buf);
 			break;
 		} else {
 			strcat(result, " ");
 			strncat(result, spaces, 8 - (strlen(result) % 8));
 			strncat(result, prev_buf, cur_buf - prev_buf);
 		}
 		prev_buf = cur_buf + 1;
 	}
 	return result;
 }
 
 static int calc_deferred_lines(struct deferred_lines *start)
 {
 	struct deferred_lines *item = start;
 	int result = 0;
 	while (item) {
 		result += 1;
 		item = item->next;
 	}
 	return result;
 }
 
 static void deferred_old_add(char *line, int line_no)
 {
 	struct deferred_lines *item = xmalloc(sizeof(struct deferred_lines));
 	item->line = xstrdup(line);
 	item->line_no = line_no;
 	item->next = NULL;
 	if (deferred_old) {
 		deferred_old_last->next = item;
 		deferred_old_last = item;
 	} else {
 		deferred_old = deferred_old_last = item;
 	}
 }
 
 static void deferred_new_add(char *line, int line_no)
 {
 	struct deferred_lines *item = xmalloc(sizeof(struct deferred_lines));
 	item->line = xstrdup(line);
 	item->line_no = line_no;
 	item->next = NULL;
 	if (deferred_new) {
 		deferred_new_last->next = item;
 		deferred_new_last = item;
 	} else {
 		deferred_new = deferred_new_last = item;
 	}
 }
 
 static void print_part_with_lcs(char *class, char *line, char *lcs)
 {
 	int line_len = strlen(line);
 	int i, j;
 	char c[2] = " ";
 	int same = 1;
 
 	j = 0;
 	for (i = 0; i < line_len; i++) {
 		c[0] = line[i];
 		if (same) {
 			if (line[i] == lcs[j])
 				j += 1;
 			else {
 				same = 0;
 				htmlf("<span class='%s'>", class);
 			}
 		} else if (line[i] == lcs[j]) {
 			same = 1;
 			htmlf("</span>");
 			j += 1;
 		}
 		html_txt(c);
 	}
 }
 
 static void print_ssdiff_line(char *class,
 			      int old_line_no,
 			      char *old_line,
 			      int new_line_no,
 			      char *new_line, int individual_chars)
 {
 	char *lcs = NULL;
+
 	if (old_line)
 		old_line = replace_tabs(old_line + 1);
 	if (new_line)
 		new_line = replace_tabs(new_line + 1);
 	if (individual_chars && old_line && new_line)
 		lcs = longest_common_subsequence(old_line, new_line);
-	html("<tr>");
-	if (old_line_no > 0)
-		htmlf("<td class='lineno'>%d</td><td class='%s'>",
-		      old_line_no, class);
-	else if (old_line)
+	html("<tr>\n");
+	if (old_line_no > 0) {
+		struct diff_filespec *old_file = cgit_get_current_old_file();
+		char *lineno_str = fmt("n%d", old_line_no);
+		char *id_str = fmt("%s#%s", is_null_sha1(old_file->sha1)?"HEAD":sha1_to_hex(old_rev_sha1), lineno_str);
+		html("<td class='lineno'><a class='no' href='");
+		html(cgit_fileurl(ctx.repo->url, "tree", old_file->path, id_str));
+		htmlf("' id='%s' name='%s'>%s</a>", lineno_str, lineno_str, lineno_str + 1);
+		html("</td>");
+		htmlf("<td class='%s'>", class);
+	} else if (old_line)
 		htmlf("<td class='lineno'></td><td class='%s'>", class);
 	else
 		htmlf("<td class='lineno'></td><td class='%s_dark'>", class);
 	if (old_line) {
 		if (lcs)
 			print_part_with_lcs("del", old_line, lcs);
 		else
 			html_txt(old_line);
 	}
 
+	html("</td>\n");
+	if (new_line_no > 0) {
+		struct diff_filespec *new_file = cgit_get_current_new_file();
+		char *lineno_str = fmt("n%d", new_line_no);
+		char *id_str = fmt("%s#%s", is_null_sha1(new_file->sha1)?"HEAD":sha1_to_hex(new_rev_sha1), lineno_str);
+		html("<td class='lineno'><a class='no' href='");
+		html(cgit_fileurl(ctx.repo->url, "tree", new_file->path, id_str));
+		htmlf("' id='%s' name='%s'>%s</a>", lineno_str, lineno_str, lineno_str + 1);
 	html("</td>");
-	if (new_line_no > 0)
-		htmlf("<td class='lineno'>%d</td><td class='%s'>",
-		      new_line_no, class);
-	else if (new_line)
+		htmlf("<td class='%s'>", class);
+	} else if (new_line)
 		htmlf("<td class='lineno'></td><td class='%s'>", class);
 	else
 		htmlf("<td class='lineno'></td><td class='%s_dark'>", class);
 	if (new_line) {
 		if (lcs)
 			print_part_with_lcs("add", new_line, lcs);
 		else
 			html_txt(new_line);
 	}
 
 	html("</td></tr>");
 	if (lcs)
 		free(lcs);
 	if (new_line)
 		free(new_line);
 	if (old_line)
 		free(old_line);
 }
 
 static void print_deferred_old_lines()
 {
 	struct deferred_lines *iter_old, *tmp;
 	iter_old = deferred_old;
 	while (iter_old) {
 		print_ssdiff_line("del", iter_old->line_no,
 				  iter_old->line, -1, NULL, 0);
 		tmp = iter_old->next;
 		free(iter_old);
 		iter_old = tmp;
 	}
 }
 
 static void print_deferred_new_lines()
 {
 	struct deferred_lines *iter_new, *tmp;
 	iter_new = deferred_new;
 	while (iter_new) {
 		print_ssdiff_line("add", -1, NULL,
 				  iter_new->line_no, iter_new->line, 0);
 		tmp = iter_new->next;
 		free(iter_new);
 		iter_new = tmp;
 	}
 }
 
 static void print_deferred_changed_lines()
 {
 	struct deferred_lines *iter_old, *iter_new, *tmp;
 	int n_old_lines = calc_deferred_lines(deferred_old);
 	int n_new_lines = calc_deferred_lines(deferred_new);
 	int individual_chars = (n_old_lines == n_new_lines ? 1 : 0);
 
 	iter_old = deferred_old;
 	iter_new = deferred_new;
 	while (iter_old || iter_new) {
 		if (iter_old && iter_new)
 			print_ssdiff_line("changed", iter_old->line_no,
 					  iter_old->line,
 					  iter_new->line_no, iter_new->line,
 					  individual_chars);
 		else if (iter_old)
 			print_ssdiff_line("changed", iter_old->line_no,
 					  iter_old->line, -1, NULL, 0);
 		else if (iter_new)
 			print_ssdiff_line("changed", -1, NULL,
 					  iter_new->line_no, iter_new->line, 0);
 		if (iter_old) {
 			tmp = iter_old->next;
 			free(iter_old);
 			iter_old = tmp;
 		}
 
 		if (iter_new) {
 			tmp = iter_new->next;
 			free(iter_new);
 			iter_new = tmp;
 		}
 	}
 }
 
 void cgit_ssdiff_print_deferred_lines()
 {
 	if (!deferred_old && !deferred_new)
 		return;
 	if (deferred_old && !deferred_new)
 		print_deferred_old_lines();
 	else if (!deferred_old && deferred_new)
 		print_deferred_new_lines();
 	else
 		print_deferred_changed_lines();
 	deferred_old = deferred_old_last = NULL;
 	deferred_new = deferred_new_last = NULL;
 }
 
 /*
  * print a single line returned from xdiff
  */
 void cgit_ssdiff_line_cb(char *line, int len)
 {
 	char c = line[len - 1];
 	line[len - 1] = '\0';
 	if (line[0] == '@') {
 		current_old_line = line_from_hunk(line, '-');
 		current_new_line = line_from_hunk(line, '+');
 	}
 
 	if (line[0] == ' ') {
 		if (deferred_old || deferred_new)
 			cgit_ssdiff_print_deferred_lines();
 		print_ssdiff_line("ctx", current_old_line, line,
 				  current_new_line, line, 0);
 		current_old_line += 1;
 		current_new_line += 1;
 	} else if (line[0] == '+') {
 		deferred_new_add(line, current_new_line);
 		current_new_line += 1;
 	} else if (line[0] == '-') {
 		deferred_old_add(line, current_old_line);
 		current_old_line += 1;
 	} else if (line[0] == '@') {
 		html("<tr><td colspan='4' class='hunk'>");
 		html_txt(line);
 		html("</td></tr>");
 	} else {
 		html("<tr><td colspan='4' class='ctx'>");
 		html_txt(line);
 		html("</td></tr>");
 	}
 	line[len - 1] = c;
 }
 
 void cgit_ssdiff_header_begin()
 {
 	current_old_line = -1;
 	current_new_line = -1;
 	html("<tr><td class='space' colspan='4'><div></div></td></tr>");
 	html("<tr><td class='head' colspan='4'>");
 }
 
 void cgit_ssdiff_header_end()
 {
 	html("</td><tr>");
 }
 
 void cgit_ssdiff_footer()
 {
 	if (deferred_old || deferred_new)
 		cgit_ssdiff_print_deferred_lines();
 	html("<tr><td class='foot' colspan='4'></td></tr>");
 }