ui-diff: Add links to increase/decrease number of context lines in diffs

Add two links to the "Diffstat" line to show more/less context lines in the
generated diff.

To support this, cgit_commit_link() and cgit_diff_link() has learned to
preserve the ctx.qry.context variable.

Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>

2 files changed, 23 insertions, 1 deletions

diff --git a/ui-diff.c b/ui-diff.c
index d3a3b2c..e0a72f7 100644
--- a/ui-diff.c
+++ b/ui-diff.c
@@ -31,263 +31,271 @@ static struct fileinfo {
         unsigned long old_size;
         unsigned long new_size;
         int binary:1;
 } *items;
 
 static int use_ssdiff = 0;
 
 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'>%d -> %d 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, 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;
+        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("</div>");
         html("<table summary='diffstat' class='diffstat'>");
         max_changes = 0;
         cgit_diff_tree(old_sha1, new_sha1, inspect_filepair, prefix);
         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;
 
         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, print_line_fn))
                 cgit_print_error("Error running diff");
         if (binary) {
diff --git a/ui-shared.c b/ui-shared.c
index e991799..c99bcec 100644
--- a/ui-shared.c
+++ b/ui-shared.c
@@ -216,297 +216,311 @@ static char *repolink(const char *title, const char *class, const char *page,
                         html("/");
                         if (path)
                                 html_url_path(path);
                 }
         } else {
                 html(ctx.cfg.script_name);
                 html("?url=");
                 html_url_arg(ctx.repo->url);
                 if (ctx.repo->url[strlen(ctx.repo->url) - 1] != '/')
                         html("/");
                 if (page) {
                         html_url_arg(page);
                         html("/");
                         if (path)
                                 html_url_arg(path);
                 }
                 delim = "&amp;";
         }
         if (head && strcmp(head, ctx.repo->defbranch)) {
                 html(delim);
                 html("h=");
                 html_url_arg(head);
                 delim = "&amp;";
         }
         return fmt("%s", delim);
 }
 
 static void reporevlink(const char *page, const char *name, const char *title,
                         const char *class, const char *head, const char *rev,
                         const char *path)
 {
         char *delim;
 
         delim = repolink(title, class, page, head, path);
         if (rev && ctx.qry.head != NULL && strcmp(rev, ctx.qry.head)) {
                 html(delim);
                 html("id=");
                 html_url_arg(rev);
         }
         html("'>");
         html_txt(name);
         html("</a>");
 }
 
 void cgit_summary_link(const char *name, const char *title, const char *class,
                        const char *head)
 {
         reporevlink(NULL, name, title, class, head, NULL, NULL);
 }
 
 void cgit_tag_link(const char *name, const char *title, const char *class,
                    const char *head, const char *rev)
 {
         reporevlink("tag", name, title, class, head, rev, NULL);
 }
 
 void cgit_tree_link(const char *name, const char *title, const char *class,
                     const char *head, const char *rev, const char *path)
 {
         reporevlink("tree", name, title, class, head, rev, path);
 }
 
 void cgit_plain_link(const char *name, const char *title, const char *class,
                      const char *head, const char *rev, const char *path)
 {
         reporevlink("plain", name, title, class, head, rev, path);
 }
 
 void cgit_log_link(const char *name, const char *title, const char *class,
                    const char *head, const char *rev, const char *path,
                    int ofs, const char *grep, const char *pattern, int showmsg)
 {
         char *delim;
 
         delim = repolink(title, class, "log", head, path);
         if (rev && strcmp(rev, ctx.qry.head)) {
                 html(delim);
                 html("id=");
                 html_url_arg(rev);
                 delim = "&";
         }
         if (grep && pattern) {
                 html(delim);
                 html("qt=");
                 html_url_arg(grep);
                 delim = "&";
                 html(delim);
                 html("q=");
                 html_url_arg(pattern);
         }
         if (ofs > 0) {
                 html(delim);
                 html("ofs=");
                 htmlf("%d", ofs);
                 delim = "&";
         }
         if (showmsg) {
                 html(delim);
                 html("showmsg=1");
         }
         html("'>");
         html_txt(name);
         html("</a>");
 }
 
 void cgit_commit_link(char *name, const char *title, const char *class,
                       const char *head, const char *rev, const char *path,
                       int toggle_ssdiff)
 {
         if (strlen(name) > ctx.cfg.max_msg_len && ctx.cfg.max_msg_len >= 15) {
                 name[ctx.cfg.max_msg_len] = '\0';
                 name[ctx.cfg.max_msg_len - 1] = '.';
                 name[ctx.cfg.max_msg_len - 2] = '.';
                 name[ctx.cfg.max_msg_len - 3] = '.';
         }
 
         char *delim;
 
         delim = repolink(title, class, "commit", head, path);
         if (rev && strcmp(rev, ctx.qry.head)) {
                 html(delim);
                 html("id=");
                 html_url_arg(rev);
                 delim = "&amp;";
         }
         if ((ctx.qry.ssdiff && !toggle_ssdiff) || (!ctx.qry.ssdiff && toggle_ssdiff)) {
                 html(delim);
                 html("ss=1");
+                delim = "&amp;";
+        }
+        if (ctx.qry.context > 0 && ctx.qry.context != 3) {
+                html(delim);
+                html("context=");
+                htmlf("%d", ctx.qry.context);
+                delim = "&amp;";
         }
         html("'>");
         html_txt(name);
         html("</a>");
 }
 
 void cgit_refs_link(const char *name, const char *title, const char *class,
                     const char *head, const char *rev, const char *path)
 {
         reporevlink("refs", name, title, class, head, rev, path);
 }
 
 void cgit_snapshot_link(const char *name, const char *title, const char *class,
                         const char *head, const char *rev,
                         const char *archivename)
 {
         reporevlink("snapshot", name, title, class, head, rev, archivename);
 }
 
 void cgit_diff_link(const char *name, const char *title, const char *class,
                     const char *head, const char *new_rev, const char *old_rev,
                     const char *path, int toggle_ssdiff)
 {
         char *delim;
 
         delim = repolink(title, class, "diff", head, path);
         if (new_rev && ctx.qry.head != NULL && strcmp(new_rev, ctx.qry.head)) {
                 html(delim);
                 html("id=");
                 html_url_arg(new_rev);
                 delim = "&amp;";
         }
         if (old_rev) {
                 html(delim);
                 html("id2=");
                 html_url_arg(old_rev);
                 delim = "&amp;";
         }
         if ((ctx.qry.ssdiff && !toggle_ssdiff) || (!ctx.qry.ssdiff && toggle_ssdiff)) {
                 html(delim);
                 html("ss=1");
+                delim = "&amp;";
+        }
+        if (ctx.qry.context > 0 && ctx.qry.context != 3) {
+                html(delim);
+                html("context=");
+                htmlf("%d", ctx.qry.context);
+                delim = "&amp;";
         }
         html("'>");
         html_txt(name);
         html("</a>");
 }
 
 void cgit_patch_link(const char *name, const char *title, const char *class,
                      const char *head, const char *rev, const char *path)
 {
         reporevlink("patch", name, title, class, head, rev, path);
 }
 
 void cgit_stats_link(const char *name, const char *title, const char *class,
                      const char *head, const char *path)
 {
         reporevlink("stats", name, title, class, head, NULL, path);
 }
 
 void cgit_self_link(char *name, const char *title, const char *class,
                     struct cgit_context *ctx)
 {
         if (!strcmp(ctx->qry.page, "repolist"))
                 return cgit_index_link(name, title, class, ctx->qry.search,
                                        ctx->qry.ofs);
         else if (!strcmp(ctx->qry.page, "summary"))
                 return cgit_summary_link(name, title, class, ctx->qry.head);
         else if (!strcmp(ctx->qry.page, "tag"))
                 return cgit_tag_link(name, title, class, ctx->qry.head,
                                      ctx->qry.has_sha1 ? ctx->qry.sha1 : NULL);
         else if (!strcmp(ctx->qry.page, "tree"))
                 return cgit_tree_link(name, title, class, ctx->qry.head,
                                       ctx->qry.has_sha1 ? ctx->qry.sha1 : NULL,
                                       ctx->qry.path);
         else if (!strcmp(ctx->qry.page, "plain"))
                 return cgit_plain_link(name, title, class, ctx->qry.head,
                                       ctx->qry.has_sha1 ? ctx->qry.sha1 : NULL,
                                       ctx->qry.path);
         else if (!strcmp(ctx->qry.page, "log"))
                 return cgit_log_link(name, title, class, ctx->qry.head,
                                       ctx->qry.has_sha1 ? ctx->qry.sha1 : NULL,
                                       ctx->qry.path, ctx->qry.ofs,
                                       ctx->qry.grep, ctx->qry.search,
                                       ctx->qry.showmsg);
         else if (!strcmp(ctx->qry.page, "commit"))
                 return cgit_commit_link(name, title, class, ctx->qry.head,
                                       ctx->qry.has_sha1 ? ctx->qry.sha1 : NULL,
                                       ctx->qry.path, 0);
         else if (!strcmp(ctx->qry.page, "patch"))
                 return cgit_patch_link(name, title, class, ctx->qry.head,
                                       ctx->qry.has_sha1 ? ctx->qry.sha1 : NULL,
                                       ctx->qry.path);
         else if (!strcmp(ctx->qry.page, "refs"))
                 return cgit_refs_link(name, title, class, ctx->qry.head,
                                       ctx->qry.has_sha1 ? ctx->qry.sha1 : NULL,
                                       ctx->qry.path);
         else if (!strcmp(ctx->qry.page, "snapshot"))
                 return cgit_snapshot_link(name, title, class, ctx->qry.head,
                                       ctx->qry.has_sha1 ? ctx->qry.sha1 : NULL,
                                       ctx->qry.path);
         else if (!strcmp(ctx->qry.page, "diff"))
                 return cgit_diff_link(name, title, class, ctx->qry.head,
                                       ctx->qry.sha1, ctx->qry.sha2,
                                       ctx->qry.path, 0);
         else if (!strcmp(ctx->qry.page, "stats"))
                 return cgit_stats_link(name, title, class, ctx->qry.head,
                                       ctx->qry.path);
 
         /* Don't known how to make link for this page */
         repolink(title, class, ctx->qry.page, ctx->qry.head, ctx->qry.path);
         html("><!-- cgit_self_link() doesn't know how to make link for page '");
         html_txt(ctx->qry.page);
         html("' -->");
         html_txt(name);
         html("</a>");
 }
 
 void cgit_object_link(struct object *obj)
 {
         char *page, *shortrev, *fullrev, *name;
 
         fullrev = sha1_to_hex(obj->sha1);
         shortrev = xstrdup(fullrev);
         shortrev[10] = '\0';
         if (obj->type == OBJ_COMMIT) {
                 cgit_commit_link(fmt("commit %s...", shortrev), NULL, NULL,
                                  ctx.qry.head, fullrev, NULL, 0);
                 return;
         } else if (obj->type == OBJ_TREE)
                 page = "tree";
         else if (obj->type == OBJ_TAG)
                 page = "tag";
         else
                 page = "blob";
         name = fmt("%s %s...", typename(obj->type), shortrev);
         reporevlink(page, name, NULL, NULL, ctx.qry.head, fullrev, NULL);
 }
 
 void cgit_print_date(time_t secs, const char *format, int local_time)
 {
         char buf[64];
         struct tm *time;
 
         if (!secs)
                 return;
         if(local_time)
                 time = localtime(&secs);
         else
                 time = gmtime(&secs);
         strftime(buf, sizeof(buf)-1, format, time);
         html_txt(buf);
 }
 
 void cgit_print_age(time_t t, time_t max_relative, const char *format)
 {
         time_t now, secs;
 
         if (!t)
                 return;
         time(&now);
         secs = now - t;
 
         if (secs > max_relative && max_relative >= 0) {
                 cgit_print_date(t, format, ctx.cfg.local_time);
                 return;
         }
 
         if (secs < TM_HOUR * 2) {
                 htmlf("<span class='age-mins'>%.0f min.</span>",