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>

cgit.css

@@ -275,7 +275,7 @@ 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;

ui-diff.c

@@ -34,6 +34,17 @@ static struct fileinfo {
 } *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)
 {
@@ -284,6 +295,7 @@ static void filepair_cb(struct diff_filepair *pair)
 	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;

ui-diff.h

@@ -7,4 +7,10 @@ extern void cgit_print_diffstat(const unsigned char *old_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 */

ui-ssdiff.c

@@ -1,6 +1,7 @@
 #include "cgit.h"
 #include "html.h"
 #include "ui-shared.h"
+#include "ui-diff.h"
 
 extern int use_ssdiff;
 
@@ -191,17 +192,24 @@ static void print_ssdiff_line(char *class,
 			      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>");
+	html("<tr>\n");
-	if (old_line_no > 0)
+	if (old_line_no > 0) {
-		htmlf("<td class='lineno'>%d</td><td class='%s'>",
+		struct diff_filespec *old_file = cgit_get_current_old_file();
-		      old_line_no, class);
+		char *lineno_str = fmt("n%d", old_line_no);
-	else if (old_line)
+		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);
@@ -212,11 +220,17 @@ static void print_ssdiff_line(char *class,
 			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='%s'>", class);
-		htmlf("<td class='lineno'>%d</td><td class='%s'>",
+	} else if (new_line)
-		      new_line_no, 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);