ui-diff: show /dev/null as filename for add/delete

The diff headers showed an invalid filename when a patch created or
deleted a file. Fix it.

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

1 files changed, 4 insertions, 1 deletions

diff --git a/ui-diff.c b/ui-diff.c
index 7ec5701..999b6f3 100644
--- a/ui-diff.c
+++ b/ui-diff.c
@@ -6,65 +6,68 @@
  *   (see COPYING for full license text)
  */
 
 #include "cgit.h"
 
 
 /*
  * 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,
                    unsigned char *sha2, char *path2)
 {
         char *abbrev1, *abbrev2;
-
+        if (is_null_sha1(sha1))
+                path1 = "dev/null";
+        if (is_null_sha1(sha2))
+                path2 = "dev/null";
         html("<tr><td>");
         html("<div class='head'>");
         html("diff --git a/");
         html_txt(path1);
         html(" b/");
         html_txt(path2);
         abbrev1 = xstrdup(find_unique_abbrev(sha1, DEFAULT_ABBREV));
         abbrev2 = xstrdup(find_unique_abbrev(sha2, DEFAULT_ABBREV));
         htmlf("\nindex %s..%s", abbrev1, abbrev2);
         free(abbrev1);
         free(abbrev2);
         html("\n--- a/");
         html_txt(path1);
         html("\n+++ b/");
         html_txt(path2);
         html("</div>");
 }
 
 static void filepair_cb(struct diff_filepair *pair)
 {
         header(pair->one->sha1, pair->one->path,
                pair->two->sha1, pair->two->path);
         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;