Be prepared for empty repositories

Before this patch, cgit would segfault on repositories with no refs.

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

2 files changed, 9 insertions, 4 deletions

diff --git a/cgit.c b/cgit.c
index 8795085..cefeddf 100644
--- a/cgit.c
+++ b/cgit.c
@@ -1,392 +1,396 @@
 /* cgit.c: cgi for the git scm
  *
  * Copyright (C) 2006 Lars Hjemli
  *
  * Licensed under GNU General Public License v2
  *   (see COPYING for full license text)
  */
 
 #include "cgit.h"
 #include "cache.h"
 #include "cmd.h"
 #include "configfile.h"
 #include "html.h"
 #include "ui-shared.h"
 
 const char *cgit_version = CGIT_VERSION;
 
 void config_cb(const char *name, const char *value)
 {
 	if (!strcmp(name, "root-title"))
 		ctx.cfg.root_title = xstrdup(value);
 	else if (!strcmp(name, "root-desc"))
 		ctx.cfg.root_desc = xstrdup(value);
 	else if (!strcmp(name, "root-readme"))
 		ctx.cfg.root_readme = xstrdup(value);
 	else if (!strcmp(name, "css"))
 		ctx.cfg.css = xstrdup(value);
 	else if (!strcmp(name, "favicon"))
 		ctx.cfg.favicon = xstrdup(value);
 	else if (!strcmp(name, "footer"))
 		ctx.cfg.footer = xstrdup(value);
 	else if (!strcmp(name, "logo"))
 		ctx.cfg.logo = xstrdup(value);
 	else if (!strcmp(name, "index-header"))
 		ctx.cfg.index_header = xstrdup(value);
 	else if (!strcmp(name, "index-info"))
 		ctx.cfg.index_info = xstrdup(value);
 	else if (!strcmp(name, "logo-link"))
 		ctx.cfg.logo_link = xstrdup(value);
 	else if (!strcmp(name, "module-link"))
 		ctx.cfg.module_link = xstrdup(value);
 	else if (!strcmp(name, "virtual-root")) {
 		ctx.cfg.virtual_root = trim_end(value, '/');
 		if (!ctx.cfg.virtual_root && (!strcmp(value, "/")))
 			ctx.cfg.virtual_root = "";
 	} else if (!strcmp(name, "nocache"))
 		ctx.cfg.nocache = atoi(value);
 	else if (!strcmp(name, "snapshots"))
 		ctx.cfg.snapshots = cgit_parse_snapshots_mask(value);
 	else if (!strcmp(name, "enable-index-links"))
 		ctx.cfg.enable_index_links = atoi(value);
 	else if (!strcmp(name, "enable-log-filecount"))
 		ctx.cfg.enable_log_filecount = atoi(value);
 	else if (!strcmp(name, "enable-log-linecount"))
 		ctx.cfg.enable_log_linecount = atoi(value);
 	else if (!strcmp(name, "cache-size"))
 		ctx.cfg.cache_size = atoi(value);
 	else if (!strcmp(name, "cache-root"))
 		ctx.cfg.cache_root = xstrdup(value);
 	else if (!strcmp(name, "cache-root-ttl"))
 		ctx.cfg.cache_root_ttl = atoi(value);
 	else if (!strcmp(name, "cache-repo-ttl"))
 		ctx.cfg.cache_repo_ttl = atoi(value);
 	else if (!strcmp(name, "cache-static-ttl"))
 		ctx.cfg.cache_static_ttl = atoi(value);
 	else if (!strcmp(name, "cache-dynamic-ttl"))
 		ctx.cfg.cache_dynamic_ttl = atoi(value);
 	else if (!strcmp(name, "max-message-length"))
 		ctx.cfg.max_msg_len = atoi(value);
 	else if (!strcmp(name, "max-repodesc-length"))
 		ctx.cfg.max_repodesc_len = atoi(value);
 	else if (!strcmp(name, "max-repo-count"))
 		ctx.cfg.max_repo_count = atoi(value);
 	else if (!strcmp(name, "max-commit-count"))
 		ctx.cfg.max_commit_count = atoi(value);
 	else if (!strcmp(name, "summary-log"))
 		ctx.cfg.summary_log = atoi(value);
 	else if (!strcmp(name, "summary-branches"))
 		ctx.cfg.summary_branches = atoi(value);
 	else if (!strcmp(name, "summary-tags"))
 		ctx.cfg.summary_tags = atoi(value);
 	else if (!strcmp(name, "agefile"))
 		ctx.cfg.agefile = xstrdup(value);
 	else if (!strcmp(name, "renamelimit"))
 		ctx.cfg.renamelimit = atoi(value);
 	else if (!strcmp(name, "robots"))
 		ctx.cfg.robots = xstrdup(value);
 	else if (!strcmp(name, "clone-prefix"))
 		ctx.cfg.clone_prefix = xstrdup(value);
 	else if (!strcmp(name, "repo.group"))
 		ctx.cfg.repo_group = xstrdup(value);
 	else if (!strcmp(name, "repo.url"))
 		ctx.repo = cgit_add_repo(value);
 	else if (!strcmp(name, "repo.name"))
 		ctx.repo->name = xstrdup(value);
 	else if (ctx.repo && !strcmp(name, "repo.path"))
 		ctx.repo->path = trim_end(value, '/');
 	else if (ctx.repo && !strcmp(name, "repo.clone-url"))
 		ctx.repo->clone_url = xstrdup(value);
 	else if (ctx.repo && !strcmp(name, "repo.desc"))
 		ctx.repo->desc = xstrdup(value);
 	else if (ctx.repo && !strcmp(name, "repo.owner"))
 		ctx.repo->owner = xstrdup(value);
 	else if (ctx.repo && !strcmp(name, "repo.defbranch"))
 		ctx.repo->defbranch = xstrdup(value);
 	else if (ctx.repo && !strcmp(name, "repo.snapshots"))
 		ctx.repo->snapshots = ctx.cfg.snapshots & cgit_parse_snapshots_mask(value); /* XXX: &? */
 	else if (ctx.repo && !strcmp(name, "repo.enable-log-filecount"))
 		ctx.repo->enable_log_filecount = ctx.cfg.enable_log_filecount * atoi(value);
 	else if (ctx.repo && !strcmp(name, "repo.enable-log-linecount"))
 		ctx.repo->enable_log_linecount = ctx.cfg.enable_log_linecount * atoi(value);
 	else if (ctx.repo && !strcmp(name, "repo.module-link"))
 		ctx.repo->module_link= xstrdup(value);
 	else if (ctx.repo && !strcmp(name, "repo.readme") && value != NULL) {
 		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")) {
 		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);
 	} else if (!strcmp(name, "path")) {
 		ctx.qry.path = trim_end(value, '/');
 	} else if (!strcmp(name, "name")) {
 		ctx.qry.name = xstrdup(value);
 	} else if (!strcmp(name, "mimetype")) {
 		ctx.qry.mimetype = xstrdup(value);
 	}
 }
 
 static void prepare_context(struct cgit_context *ctx)
 {
 	memset(ctx, 0, sizeof(ctx));
 	ctx->cfg.agefile = "info/web/last-modified";
 	ctx->cfg.nocache = 0;
 	ctx->cfg.cache_size = 0;
 	ctx->cfg.cache_dynamic_ttl = 5;
 	ctx->cfg.cache_max_create_time = 5;
 	ctx->cfg.cache_repo_ttl = 5;
 	ctx->cfg.cache_root = CGIT_CACHE_ROOT;
 	ctx->cfg.cache_root_ttl = 5;
 	ctx->cfg.cache_static_ttl = -1;
 	ctx->cfg.css = "/cgit.css";
 	ctx->cfg.logo = "/git-logo.png";
 	ctx->cfg.max_repo_count = 50;
 	ctx->cfg.max_commit_count = 50;
 	ctx->cfg.max_lock_attempts = 5;
 	ctx->cfg.max_msg_len = 60;
 	ctx->cfg.max_repodesc_len = 60;
 	ctx->cfg.module_link = "./?repo=%s&page=commit&id=%s";
 	ctx->cfg.renamelimit = -1;
 	ctx->cfg.robots = "index, nofollow";
 	ctx->cfg.root_title = "Git repository browser";
 	ctx->cfg.root_desc = "a fast webinterface for the git dscm";
 	ctx->cfg.script_name = CGIT_SCRIPT_NAME;
 	ctx->page.mimetype = "text/html";
 	ctx->page.charset = PAGE_ENCODING;
 	ctx->page.filename = NULL;
 	ctx->page.modified = time(NULL);
 	ctx->page.expires = ctx->page.modified;
 }
 
 struct refmatch {
 	char *req_ref;
 	char *first_ref;
 	int match;
 };
 
 int find_current_ref(const char *refname, const unsigned char *sha1,
 		     int flags, void *cb_data)
 {
 	struct refmatch *info;
 
 	info = (struct refmatch *)cb_data;
 	if (!strcmp(refname, info->req_ref))
 		info->match = 1;
 	if (!info->first_ref)
 		info->first_ref = xstrdup(refname);
 	return info->match;
 }
 
 char *find_default_branch(struct cgit_repo *repo)
 {
 	struct refmatch info;
+	char *ref;
 
 	info.req_ref = repo->defbranch;
 	info.first_ref = NULL;
 	info.match = 0;
 	for_each_branch_ref(find_current_ref, &info);
 	if (info.match)
-		return info.req_ref;
+		ref = info.req_ref;
 	else
-		return info.first_ref;
+		ref = info.first_ref;
+	if (ref)
+		ref = xstrdup(ref);
+	return ref;
 }
 
 static int prepare_repo_cmd(struct cgit_context *ctx)
 {
 	char *tmp;
 	unsigned char sha1[20];
 	int nongit = 0;
 
 	setenv("GIT_DIR", ctx->repo->path, 1);
 	setup_git_directory_gently(&nongit);
 	if (nongit) {
 		ctx->page.title = fmt("%s - %s", ctx->cfg.root_title,
 				      "config error");
 		tmp = fmt("Not a git repository: '%s'", ctx->repo->path);
 		ctx->repo = NULL;
 		cgit_print_http_headers(ctx);
 		cgit_print_docstart(ctx);
 		cgit_print_pageheader(ctx);
 		cgit_print_error(tmp);
 		cgit_print_docend();
 		return 1;
 	}
 	ctx->page.title = fmt("%s - %s", ctx->repo->name, ctx->repo->desc);
 
 	if (!ctx->qry.head) {
-		ctx->qry.head = xstrdup(find_default_branch(ctx->repo));
+		ctx->qry.head = find_default_branch(ctx->repo);
 		ctx->repo->defbranch = ctx->qry.head;
 	}
 
 	if (!ctx->qry.head) {
 		cgit_print_http_headers(ctx);
 		cgit_print_docstart(ctx);
 		cgit_print_pageheader(ctx);
 		cgit_print_error("Repository seems to be empty");
 		cgit_print_docend();
 		return 1;
 	}
 
 	if (get_sha1(ctx->qry.head, sha1)) {
 		tmp = xstrdup(ctx->qry.head);
 		ctx->qry.head = ctx->repo->defbranch;
 		cgit_print_http_headers(ctx);
 		cgit_print_docstart(ctx);
 		cgit_print_pageheader(ctx);
 		cgit_print_error(fmt("Invalid branch: %s", tmp));
 		cgit_print_docend();
 		return 1;
 	}
 	return 0;
 }
 
 static void process_request(void *cbdata)
 {
 	struct cgit_context *ctx = cbdata;
 	struct cgit_cmd *cmd;
 
 	cmd = cgit_get_cmd(ctx);
 	if (!cmd) {
 		ctx->page.title = "cgit error";
 		ctx->repo = NULL;
 		cgit_print_http_headers(ctx);
 		cgit_print_docstart(ctx);
 		cgit_print_pageheader(ctx);
 		cgit_print_error("Invalid request");
 		cgit_print_docend();
 		return;
 	}
 
 	if (cmd->want_repo && !ctx->repo) {
 		cgit_print_http_headers(ctx);
 		cgit_print_docstart(ctx);
 		cgit_print_pageheader(ctx);
 		cgit_print_error(fmt("No repository selected"));
 		cgit_print_docend();
 		return;
 	}
 
 	if (ctx->repo && prepare_repo_cmd(ctx))
 		return;
 
 	if (cmd->want_layout) {
 		cgit_print_http_headers(ctx);
 		cgit_print_docstart(ctx);
 		cgit_print_pageheader(ctx);
 	}
 
 	cmd->fn(ctx);
 
 	if (cmd->want_layout)
 		cgit_print_docend();
 }
 
 static void cgit_parse_args(int argc, const char **argv)
 {
 	int i;
 
 	for (i = 1; i < argc; i++) {
 		if (!strncmp(argv[i], "--cache=", 8)) {
 			ctx.cfg.cache_root = xstrdup(argv[i]+8);
 		}
 		if (!strcmp(argv[i], "--nocache")) {
 			ctx.cfg.nocache = 1;
 		}
 		if (!strncmp(argv[i], "--query=", 8)) {
 			ctx.qry.raw = xstrdup(argv[i]+8);
 		}
 		if (!strncmp(argv[i], "--repo=", 7)) {
 			ctx.qry.repo = xstrdup(argv[i]+7);
 		}
 		if (!strncmp(argv[i], "--page=", 7)) {
 			ctx.qry.page = xstrdup(argv[i]+7);
 		}
 		if (!strncmp(argv[i], "--head=", 7)) {
 			ctx.qry.head = xstrdup(argv[i]+7);
 			ctx.qry.has_symref = 1;
 		}
 		if (!strncmp(argv[i], "--sha1=", 7)) {
 			ctx.qry.sha1 = xstrdup(argv[i]+7);
 			ctx.qry.has_sha1 = 1;
 		}
 		if (!strncmp(argv[i], "--ofs=", 6)) {
 			ctx.qry.ofs = atoi(argv[i]+6);
 		}
 	}
 }
 
 static int calc_ttl()
 {
 	if (!ctx.repo)
 		return ctx.cfg.cache_root_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");
 	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);
 
 	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/ui-shared.c b/ui-shared.c
index 209af6e..4280a70 100644
--- a/ui-shared.c
+++ b/ui-shared.c
@@ -265,408 +265,409 @@ void cgit_log_link(char *name, char *title, char *class, char *head,
 		html_attr(pattern);
 	}
 	if (ofs > 0) {
 		html(delim);
 		html("ofs=");
 		htmlf("%d", ofs);
 	}
 	html("'>");
 	html_txt(name);
 	html("</a>");
 }
 
 void cgit_commit_link(char *name, char *title, char *class, char *head,
 		      char *rev)
 {
 	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] = '.';
 	}
 	reporevlink("commit", name, title, class, head, rev, NULL);
 }
 
 void cgit_refs_link(char *name, char *title, char *class, char *head,
 		    char *rev, char *path)
 {
 	reporevlink("refs", name, title, class, head, rev, path);
 }
 
 void cgit_snapshot_link(char *name, char *title, char *class, char *head,
 			char *rev, char *archivename)
 {
 	reporevlink("snapshot", name, title, class, head, rev, archivename);
 }
 
 void cgit_diff_link(char *name, char *title, char *class, char *head,
 		    char *new_rev, char *old_rev, char *path)
 {
 	char *delim;
 
 	delim = repolink(title, class, "diff", head, path);
 	if (new_rev && strcmp(new_rev, ctx.qry.head)) {
 		html(delim);
 		html("id=");
 		html_attr(new_rev);
 		delim = "&amp;";
 	}
 	if (old_rev) {
 		html(delim);
 		html("id2=");
 		html_attr(old_rev);
 	}
 	html("'>");
 	html_txt(name);
 	html("</a>");
 }
 
 void cgit_patch_link(char *name, char *title, char *class, char *head,
 		     char *rev)
 {
 	reporevlink("patch", name, title, class, head, rev, NULL);
 }
 
 void cgit_object_link(struct object *obj)
 {
 	char *page, *arg, *url;
 
 	if (obj->type == OBJ_COMMIT) {
                 cgit_commit_link(fmt("commit %s", sha1_to_hex(obj->sha1)), NULL, NULL,
 				 ctx.qry.head, sha1_to_hex(obj->sha1));
 		return;
 	} else if (obj->type == OBJ_TREE) {
 		page = "tree";
 		arg = "id";
 	} else if (obj->type == OBJ_TAG) {
 		page = "tag";
 		arg = "id";
 	} else {
 		page = "blob";
 		arg = "id";
 	}
 
 	url = cgit_pageurl(ctx.qry.repo, page,
 			   fmt("%s=%s", arg, sha1_to_hex(obj->sha1)));
 	html_link_open(url, NULL, NULL);
 	htmlf("%s %s", typename(obj->type),
 	      sha1_to_hex(obj->sha1));
 	html_link_close();
 }
 
 void cgit_print_date(time_t secs, char *format)
 {
 	char buf[64];
 	struct tm *time;
 
 	if (!secs)
 		return;
 	time = gmtime(&secs);
 	strftime(buf, sizeof(buf)-1, format, time);
 	html_txt(buf);
 }
 
 void cgit_print_age(time_t t, time_t max_relative, 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);
 		return;
 	}
 
 	if (secs < TM_HOUR * 2) {
 		htmlf("<span class='age-mins'>%.0f min.</span>",
 		      secs * 1.0 / TM_MIN);
 		return;
 	}
 	if (secs < TM_DAY * 2) {
 		htmlf("<span class='age-hours'>%.0f hours</span>",
 		      secs * 1.0 / TM_HOUR);
 		return;
 	}
 	if (secs < TM_WEEK * 2) {
 		htmlf("<span class='age-days'>%.0f days</span>",
 		      secs * 1.0 / TM_DAY);
 		return;
 	}
 	if (secs < TM_MONTH * 2) {
 		htmlf("<span class='age-weeks'>%.0f weeks</span>",
 		      secs * 1.0 / TM_WEEK);
 		return;
 	}
 	if (secs < TM_YEAR * 2) {
 		htmlf("<span class='age-months'>%.0f months</span>",
 		      secs * 1.0 / TM_MONTH);
 		return;
 	}
 	htmlf("<span class='age-years'>%.0f years</span>",
 	      secs * 1.0 / TM_YEAR);
 }
 
 void cgit_print_http_headers(struct cgit_context *ctx)
 {
 	if (ctx->page.mimetype && ctx->page.charset)
 		htmlf("Content-Type: %s; charset=%s\n", ctx->page.mimetype,
 		      ctx->page.charset);
 	else if (ctx->page.mimetype)
 		htmlf("Content-Type: %s\n", ctx->page.mimetype);
 	if (ctx->page.filename)
 		htmlf("Content-Disposition: inline; filename=\"%s\"\n",
 		      ctx->page.filename);
 	htmlf("Last-Modified: %s\n", http_date(ctx->page.modified));
 	htmlf("Expires: %s\n", http_date(ctx->page.expires));
 	html("\n");
 }
 
 void cgit_print_docstart(struct cgit_context *ctx)
 {
 	html(cgit_doctype);
 	html("<html xmlns='http://www.w3.org/1999/xhtml' xml:lang='en' lang='en'>\n");
 	html("<head>\n");
 	html("<title>");
 	html_txt(ctx->page.title);
 	html("</title>\n");
 	htmlf("<meta name='generator' content='cgit %s'/>\n", cgit_version);
 	if (ctx->cfg.robots && *ctx->cfg.robots)
 		htmlf("<meta name='robots' content='%s'/>\n", ctx->cfg.robots);
 	html("<link rel='stylesheet' type='text/css' href='");
 	html_attr(ctx->cfg.css);
 	html("'/>\n");
 	if (ctx->cfg.favicon) {
 		html("<link rel='shortcut icon' href='");
 		html_attr(ctx->cfg.favicon);
 		html("'/>\n");
 	}
 	html("</head>\n");
 	html("<body>\n");
 }
 
 void cgit_print_docend()
 {
 	html("</div>");
 	if (ctx.cfg.footer)
 		html_include(ctx.cfg.footer);
 	else {
 		html("<div class='footer'>generated ");
 		cgit_print_date(time(NULL), FMT_LONGDATE);
 		htmlf(" by cgit %s", cgit_version);
 		html("</div>\n");
 	}
 	html("</body>\n</html>\n");
 }
 
 int print_branch_option(const char *refname, const unsigned char *sha1,
 			int flags, void *cb_data)
 {
 	char *name = (char *)refname;
 	html_option(name, name, ctx.qry.head);
 	return 0;
 }
 
 int print_archive_ref(const char *refname, const unsigned char *sha1,
 		       int flags, void *cb_data)
 {
 	struct tag *tag;
 	struct taginfo *info;
 	struct object *obj;
 	char buf[256], *url;
 	unsigned char fileid[20];
 	int *header = (int *)cb_data;
 
 	if (prefixcmp(refname, "refs/archives"))
 		return 0;
 	strncpy(buf, refname+14, sizeof(buf));
 	obj = parse_object(sha1);
 	if (!obj)
 		return 1;
 	if (obj->type == OBJ_TAG) {
 		tag = lookup_tag(sha1);
 		if (!tag || parse_tag(tag) || !(info = cgit_parse_tag(tag)))
 			return 0;
 		hashcpy(fileid, tag->tagged->sha1);
 	} else if (obj->type != OBJ_BLOB) {
 		return 0;
 	} else {
 		hashcpy(fileid, sha1);
 	}
 	if (!*header) {
 		html("<h1>download</h1>\n");
 		*header = 1;
 	}
 	url = cgit_pageurl(ctx.qry.repo, "blob",
 			   fmt("id=%s&amp;path=%s", sha1_to_hex(fileid),
 			       buf));
 	html_link_open(url, NULL, "menu");
 	html_txt(strlpart(buf, 20));
 	html_link_close();
 	return 0;
 }
 
 void add_hidden_formfields(int incl_head, int incl_search, char *page)
 {
 	char *url;
 
 	if (!ctx.cfg.virtual_root) {
 		url = fmt("%s/%s", ctx.qry.repo, page);
 		if (ctx.qry.path)
 			url = fmt("%s/%s", url, ctx.qry.path);
 		html_hidden("url", url);
 	}
 
-	if (incl_head && strcmp(ctx.qry.head, ctx.repo->defbranch))
+	if (incl_head && ctx.qry.head && ctx.repo->defbranch &&
+	    strcmp(ctx.qry.head, ctx.repo->defbranch))
 		html_hidden("h", ctx.qry.head);
 
 	if (ctx.qry.sha1)
 		html_hidden("id", ctx.qry.sha1);
 	if (ctx.qry.sha2)
 		html_hidden("id2", ctx.qry.sha2);
 
 	if (incl_search) {
 		if (ctx.qry.grep)
 			html_hidden("qt", ctx.qry.grep);
 		if (ctx.qry.search)
 			html_hidden("q", ctx.qry.search);
 	}
 }
 
 char *hc(struct cgit_cmd *cmd, const char *page)
 {
 	return (strcmp(cmd->name, page) ? NULL : "active");
 }
 
 void cgit_print_pageheader(struct cgit_context *ctx)
 {
 	struct cgit_cmd *cmd = cgit_get_cmd(ctx);
 
 	html("<table id='header'>\n");
 	html("<tr>\n");
 	html("<td class='logo' rowspan='2'><a href='");
 	if (ctx->cfg.logo_link)
 		html_attr(ctx->cfg.logo_link);
 	else
 		html_attr(cgit_rooturl());
 	html("'><img src='");
 	html_attr(ctx->cfg.logo);
 	html("' alt='cgit logo'/></a></td>\n");
 
 	html("<td class='main'>");
 	if (ctx->repo) {
 		cgit_index_link("index", NULL, NULL, NULL, 0);
 		html(" : ");
 		reporevlink(NULL, ctx->repo->name, NULL, hc(cmd, "summary"),
 			    ctx->qry.head, NULL, NULL);
 		html("</td><td class='form'>");
 		html("<form method='get' action=''>\n");
 		add_hidden_formfields(0, 1, ctx->qry.page);
 		html("<select name='h' onchange='this.form.submit();'>\n");
 		for_each_branch_ref(print_branch_option, ctx->qry.head);
 		html("</select> ");
 		html("<input type='submit' name='' value='switch'/>");
 		html("</form>");
 	} else
 		html_txt(ctx->cfg.root_title);
 	html("</td></tr>\n");
 
 	html("<tr><td class='sub'>");
 	if (ctx->repo) {
 		html_txt(ctx->repo->desc);
 		html("</td><td class='sub right'>");
 		html_txt(ctx->repo->owner);
 	} else {
 		if (ctx->cfg.root_desc)
 			html_txt(ctx->cfg.root_desc);
 		else if (ctx->cfg.index_info)
 			html_include(ctx->cfg.index_info);
 	}
 	html("</td></tr></table>\n");
 
 	html("<table class='tabs'><tr><td>\n");
 	if (ctx->repo) {
 		reporevlink(NULL, "summary", NULL, hc(cmd, "summary"),
 			    ctx->qry.head, NULL, NULL);
 		cgit_refs_link("refs", NULL, hc(cmd, "refs"), ctx->qry.head,
 			       ctx->qry.sha1, NULL);
 		cgit_log_link("log", NULL, hc(cmd, "log"), ctx->qry.head,
 			      NULL, NULL, 0, NULL, NULL);
 		cgit_tree_link("tree", NULL, hc(cmd, "tree"), ctx->qry.head,
 			       ctx->qry.sha1, NULL);
 		cgit_commit_link("commit", NULL, hc(cmd, "commit"),
 				 ctx->qry.head, ctx->qry.sha1);
 		cgit_diff_link("diff", NULL, hc(cmd, "diff"), ctx->qry.head,
 			       ctx->qry.sha1, ctx->qry.sha2, NULL);
 		if (ctx->repo->readme)
 			reporevlink("about", "about", NULL,
 				    hc(cmd, "about"), ctx->qry.head, NULL,
 				    NULL);
 		html("</td><td class='form'>");
 		html("<form class='right' method='get' action='");
 		if (ctx->cfg.virtual_root)
 			html_attr(cgit_fileurl(ctx->qry.repo, "log",
 					       ctx->qry.path, NULL));
 		html("'>\n");
 		add_hidden_formfields(1, 0, "log");
 		html("<select name='qt'>\n");
 		html_option("grep", "log msg", ctx->qry.grep);
 		html_option("author", "author", ctx->qry.grep);
 		html_option("committer", "committer", ctx->qry.grep);
 		html("</select>\n");
 		html("<input class='txt' type='text' size='10' name='q' value='");
 		html_attr(ctx->qry.search);
 		html("'/>\n");
 		html("<input type='submit' value='search'/>\n");
 		html("</form>\n");
 	} else {
 		site_link(NULL, "index", NULL, hc(cmd, "repolist"), NULL, 0);
 		if (ctx->cfg.root_readme)
 			site_link("about", "about", NULL, hc(cmd, "about"),
 				  NULL, 0);
 		html("</td><td class='form'>");
 		html("<form method='get' action='");
 		html_attr(cgit_rooturl());
 		html("'>\n");
 		html("<input type='text' name='q' size='10' value='");
 		html_attr(ctx->qry.search);
 		html("'/>\n");
 		html("<input type='submit' value='search'/>\n");
 		html("</form>");
 	}
 	html("</td></tr></table>\n");
 	html("<div class='content'>");
 }
 
 void cgit_print_filemode(unsigned short mode)
 {
 	if (S_ISDIR(mode))
 		html("d");
 	else if (S_ISLNK(mode))
 		html("l");
 	else if (S_ISGITLINK(mode))
 		html("m");
 	else
 		html("-");
 	html_fileperm(mode >> 6);
 	html_fileperm(mode >> 3);
 	html_fileperm(mode);
 }
 
 void cgit_print_snapshot_links(const char *repo, const char *head,
 			       const char *hex, int snapshots)
 {
 	const struct cgit_snapshot_format* f;
     	char *filename;
 
 	for (f = cgit_snapshot_formats; f->suffix; f++) {
 		if (!(snapshots & f->bit))
 			continue;
 		filename = fmt("%s-%s%s", cgit_repobasename(repo), hex,
 			       f->suffix);
 		cgit_snapshot_link(filename, NULL, NULL, (char *)head,
 				   (char *)hex, filename);
 		html("<br/>");
 	}
 }