ui-tree: add support for source-filter option

This new option is used to specify an external command which will be
executed when displaying blob content in the tree view. Blob content
will be written to STDIN of the filter and STDOUT from the filter
will be included verbatim in the html output from cgit. The file name
of the blob will be passed as the only argument to the filter command.

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

4 files changed, 25 insertions, 4 deletions

diff --git a/cgit.c b/cgit.c
index 779a464..eb7b45d 100644
--- a/cgit.c
+++ b/cgit.c
@@ -101,4 +101,6 @@ void config_cb(const char *name, const char *value)
         else if (!strcmp(name, "max-commit-count"))
                 ctx.cfg.max_commit_count = atoi(value);
+        else if (!strcmp(name, "source-filter"))
+                ctx.cfg.source_filter = new_filter(value, 1);
         else if (!strcmp(name, "summary-log"))
                 ctx.cfg.summary_log = atoi(value);
diff --git a/cgit.h b/cgit.h
index d0fff1f..f9cf0df 100644
--- a/cgit.h
+++ b/cgit.h
@@ -184,4 +184,5 @@ struct cgit_config {
         int summary_log;
         int summary_tags;
+        struct cgit_filter *source_filter;
 };
 
diff --git a/cgitrc.5.txt b/cgitrc.5.txt
index a207fe0..d420ad4 100644
--- a/cgitrc.5.txt
+++ b/cgitrc.5.txt
@@ -199,4 +199,12 @@ snapshots::
         Default value: none.
 
+source-filter::
+        Specifies a command which will be invoked to format plaintext blobs
+        in the tree view. The command will get the blob content on its STDIN
+        and the name of the blob as its only command line argument. The STDOUT
+        from the command will be included verbatim as the blob contents, i.e.
+        this can be used to implement e.g. syntax highlighting. Default value:
+        none.
+
 summary-branches::
         Specifies the number of branches to display in the repository "summary"
diff --git a/ui-tree.c b/ui-tree.c
index 553dbaa..816e121 100644
--- a/ui-tree.c
+++ b/ui-tree.c
@@ -16,5 +16,5 @@ char *match_path;
 int header = 0;
 
-static void print_text_buffer(char *buf, unsigned long size)
+static void print_text_buffer(const char *name, char *buf, unsigned long size)
 {
         unsigned long lineno, idx;
@@ -23,4 +23,14 @@ static void print_text_buffer(char *buf, unsigned long size)
 
         html("<table summary='blob content' class='blob'>\n");
+        if (ctx.cfg.source_filter) {
+                html("<tr><td class='lines'><pre><code>");
+                ctx.cfg.source_filter->argv[1] = xstrdup(name);
+                cgit_open_filter(ctx.cfg.source_filter);
+                write(STDOUT_FILENO, buf, size);
+                cgit_close_filter(ctx.cfg.source_filter);
+                html("</code></pre></td></tr></table>\n");
+                return;
+        }
+
         html("<tr><td class='linenumbers'><pre>");
         idx = 0;
@@ -66,5 +76,5 @@ static void print_binary_buffer(char *buf, unsigned long size)
 }
 
-static void print_object(const unsigned char *sha1, char *path)
+static void print_object(const unsigned char *sha1, char *path, const char *basename)
 {
         enum object_type type;
@@ -94,5 +104,5 @@ static void print_object(const unsigned char *sha1, char *path)
                 print_binary_buffer(buf, size);
         else
-                print_text_buffer(buf, size);
+                print_text_buffer(basename, buf, size);
 }
 
@@ -214,5 +224,5 @@ static int walk_tree(const unsigned char *sha1, const char *base, int baselen,
                         return READ_TREE_RECURSIVE;
                 } else {
-                        print_object(sha1, buffer);
+                        print_object(sha1, buffer, pathname);
                         return 0;
                 }