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
@@ -117,32 +117,33 @@ void config_cb(const char *name, const char *value)
                 if (*value == '/')
                         ctx.repo->readme = xstrdup(value);
                 else
                         ctx.repo->readme = xstrdup(fmt("%s/%s", ctx.repo->path, value));
         } else if (!strcmp(name, "include"))
                 parse_configfile(value, config_cb);
 }
 
 static void querystring_cb(const char *name, const char *value)
 {
         if (!strcmp(name,"r")) {
                 ctx.qry.repo = xstrdup(value);
                 ctx.repo = cgit_get_repoinfo(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);
         } else if (!strcmp(name, "q")) {
                 ctx.qry.search = xstrdup(value);
         } else if (!strcmp(name, "h")) {
                 ctx.qry.head = xstrdup(value);
                 ctx.qry.has_symref = 1;
         } else if (!strcmp(name, "id")) {
                 ctx.qry.sha1 = xstrdup(value);
                 ctx.qry.has_sha1 = 1;
         } else if (!strcmp(name, "id2")) {
                 ctx.qry.sha2 = xstrdup(value);
                 ctx.qry.has_sha1 = 1;
         } else if (!strcmp(name, "ofs")) {
                 ctx.qry.ofs = atoi(value);
@@ -360,44 +361,70 @@ static int calc_ttl()
 
         if (!ctx.qry.page)
                 return ctx.cfg.cache_repo_ttl;
 
         if (ctx.qry.has_symref)
                 return ctx.cfg.cache_dynamic_ttl;
 
         if (ctx.qry.has_sha1)
                 return ctx.cfg.cache_static_ttl;
 
         return ctx.cfg.cache_repo_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);
         cgit_repolist.length = 0;
         cgit_repolist.count = 0;
         cgit_repolist.repos = NULL;
 
         parse_configfile(cgit_config_env ? cgit_config_env : CGIT_CONFIG,
                          config_cb);
         ctx.repo = NULL;
         if (getenv("SCRIPT_NAME"))
                 ctx.cfg.script_name = xstrdup(getenv("SCRIPT_NAME"));
         if (getenv("QUERY_STRING"))
                 ctx.qry.raw = xstrdup(getenv("QUERY_STRING"));
         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)
                 ctx.cfg.cache_size = 0;
         err = cache_process(ctx.cfg.cache_size, ctx.cfg.cache_root,
                             ctx.qry.raw, ttl, process_request, &ctx);
         if (err)
                 cgit_print_error(fmt("Error processing page: %s (%d)",
                                      strerror(err), err));
         return err;
 }
diff --git a/cgit.h b/cgit.h
index 08fd95a..d07185c 100644
--- a/cgit.h
+++ b/cgit.h
@@ -105,32 +105,33 @@ struct reflist {
 };
 
 struct cgit_query {
         int has_symref;
         int has_sha1;
         char *raw;
         char *repo;
         char *page;
         char *search;
         char *grep;
         char *head;
         char *sha1;
         char *sha2;
         char *path;
         char *name;
         char *mimetype;
+        char *url;
         int   ofs;
 };
 
 struct cgit_config {
         char *agefile;
         char *cache_root;
         char *clone_prefix;
         char *css;
         char *favicon;
         char *footer;
         char *index_header;
         char *index_info;
         char *logo;
         char *logo_link;
         char *module_link;
         char *repo_group;