Teach cgit how to use PATH_INFO

This commit makes cgit use the cgi variables SCRIPT_NAME and PATH_INFO
when virtual-root is unspecified in cgitrc and no url-parameter is
specified on the querystring. This has two nice effects:

* Virtual urls works out of the box, no more need for rewrite-rules in httpd.
* Virtual urls with special querystring characters are handled correctly.

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

2 files changed, 28 insertions, 0 deletions

diff --git a/cgit.c b/cgit.c
index 497337b..a47cad0 100644
--- a/cgit.c
+++ b/cgit.c
@@ -130,6 +130,7 @@ static void querystring_cb(const char *name, const char *value)
         } else if (!strcmp(name, "p")) {
                 ctx.qry.page = xstrdup(value);
         } else if (!strcmp(name, "url")) {
+                ctx.qry.url = xstrdup(value);
                 cgit_parse_url(value);
         } else if (!strcmp(name, "qt")) {
                 ctx.qry.grep = xstrdup(value);
@@ -373,6 +374,8 @@ static int calc_ttl()
 int main(int argc, const char **argv)
 {
         const char *cgit_config_env = getenv("CGIT_CONFIG");
+        const char *path;
+        char *qry;
         int err, ttl;
 
         prepare_context(&ctx);
@@ -390,6 +393,30 @@ int main(int argc, const char **argv)
         cgit_parse_args(argc, argv);
         http_parse_querystring(ctx.qry.raw, querystring_cb);
 
+        /* If virtual-root isn't specified in cgitrc and no url
+         * parameter is specified on the querystring, lets pretend
+         * that virtualroot equals SCRIPT_NAME and use PATH_INFO as
+         * url. This allows cgit to work with virtual urls without
+         * the need for rewriterules in the webserver (as long as
+         * PATH_INFO is included in the cache lookup key).
+         */
+        if (!ctx.cfg.virtual_root && !ctx.qry.url) {
+                ctx.cfg.virtual_root = ctx.cfg.script_name;
+                path = getenv("PATH_INFO");
+                if (path) {
+                        if (path[0] == '/')
+                                path++;
+                        ctx.qry.url = xstrdup(path);
+                        if (ctx.qry.raw) {
+                                qry = ctx.qry.raw;
+                                ctx.qry.raw = xstrdup(fmt("%s?%s", path, qry));
+                                free(qry);
+                        } else
+                                ctx.qry.raw = ctx.qry.url;
+                        cgit_parse_url(ctx.qry.url);
+                }
+        }
+
         ttl = calc_ttl();
         ctx.page.expires += ttl*60;
         if (ctx.cfg.nocache)
diff --git a/cgit.h b/cgit.h
index 08fd95a..d07185c 100644
--- a/cgit.h
+++ b/cgit.h
@@ -118,6 +118,7 @@ struct cgit_query {
         char *path;
         char *name;
         char *mimetype;
+        char *url;
         int   ofs;
 };