Improve initialization of git directory

Using the functions offered by libgit feels like the right thing to do. Also,
make sure that config errors gets properly reported.

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

2 files changed, 9 insertions, 10 deletions

diff --git a/cgit.c b/cgit.c
index b270fdc..2c933dc 100644
--- a/cgit.c
+++ b/cgit.c
@@ -1,303 +1,302 @@
 /* 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"
 
 static int cgit_prepare_cache(struct cacheitem *item)
 {
         if (!ctx.repo && ctx.qry.repo) {
                 char *title = fmt("%s - %s", ctx.cfg.root_title, "Bad request");
                 cgit_print_docstart(title, item);
                 cgit_print_pageheader(title, 0);
                 cgit_print_error(fmt("Unknown repo: %s", ctx.qry.repo));
                 cgit_print_docend();
                 return 0;
         }
 
         if (!ctx.repo) {
                 item->name = xstrdup(fmt("%s/index.html", ctx.cfg.cache_root));
                 item->ttl = ctx.cfg.cache_root_ttl;
                 return 1;
         }
 
         if (!cgit_cmd) {
                 item->name = xstrdup(fmt("%s/%s/index.%s.html", ctx.cfg.cache_root,
                                          cache_safe_filename(ctx.repo->url),
                                          cache_safe_filename(ctx.qry.raw)));
                 item->ttl = ctx.cfg.cache_repo_ttl;
         } else {
                 item->name = xstrdup(fmt("%s/%s/%s/%s.html", ctx.cfg.cache_root,
                                          cache_safe_filename(ctx.repo->url),
                                          ctx.qry.page,
                                          cache_safe_filename(ctx.qry.raw)));
                 if (ctx.qry.has_symref)
                         item->ttl = ctx.cfg.cache_dynamic_ttl;
                 else if (ctx.qry.has_sha1)
                         item->ttl = ctx.cfg.cache_static_ttl;
                 else
                         item->ttl = ctx.cfg.cache_repo_ttl;
         }
         return 1;
 }
 
 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;
 
         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;
         else
                 return info.first_ref;
 }
 
 static void cgit_print_repo_page(struct cacheitem *item)
 {
         char *title, *tmp;
         int show_search;
         unsigned char sha1[20];
+        int nongit = 0;
 
-        if (chdir(ctx.repo->path)) {
-                title = fmt("%s - %s", ctx.cfg.root_title, "Bad request");
+        setenv("GIT_DIR", ctx.repo->path, 1);
+        setup_git_directory_gently(&nongit);
+        if (nongit) {
+                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_docstart(title, item);
                 cgit_print_pageheader(title, 0);
-                cgit_print_error(fmt("Unable to scan repository: %s",
-                                     strerror(errno)));
+                cgit_print_error(tmp);
                 cgit_print_docend();
                 return;
         }
 
         title = fmt("%s - %s", ctx.repo->name, ctx.repo->desc);
         show_search = 0;
-        setenv("GIT_DIR", ctx.repo->path, 1);
 
         if (!ctx.qry.head) {
                 ctx.qry.head = xstrdup(find_default_branch(ctx.repo));
                 ctx.repo->defbranch = ctx.qry.head;
         }
 
         if (!ctx.qry.head) {
                 cgit_print_docstart(title, item);
                 cgit_print_pageheader(title, 0);
                 cgit_print_error("Repository seems to be empty");
                 cgit_print_docend();
                 return;
         }
 
         if (get_sha1(ctx.qry.head, sha1)) {
                 tmp = xstrdup(ctx.qry.head);
                 ctx.qry.head = ctx.repo->defbranch;
                 cgit_print_docstart(title, item);
                 cgit_print_pageheader(title, 0);
                 cgit_print_error(fmt("Invalid branch: %s", tmp));
                 cgit_print_docend();
                 return;
         }
 
         if ((cgit_cmd == CMD_SNAPSHOT) && ctx.repo->snapshots) {
                 cgit_print_snapshot(item, ctx.qry.head, ctx.qry.sha1,
                                     cgit_repobasename(ctx.repo->url),
                                     ctx.qry.path,
                                     ctx.repo->snapshots );
                 return;
         }
 
         if (cgit_cmd == CMD_PATCH) {
                 cgit_print_patch(ctx.qry.sha1, item);
                 return;
         }
 
         if (cgit_cmd == CMD_BLOB) {
                 cgit_print_blob(item, ctx.qry.sha1, ctx.qry.path);
                 return;
         }
 
         show_search = (cgit_cmd == CMD_LOG);
         cgit_print_docstart(title, item);
         if (!cgit_cmd) {
                 cgit_print_pageheader("summary", show_search);
                 cgit_print_summary();
                 cgit_print_docend();
                 return;
         }
 
         cgit_print_pageheader(ctx.qry.page, show_search);
 
         switch(cgit_cmd) {
         case CMD_LOG:
                 cgit_print_log(ctx.qry.sha1, ctx.qry.ofs,
                                ctx.cfg.max_commit_count, ctx.qry.grep, ctx.qry.search,
                                ctx.qry.path, 1);
                 break;
         case CMD_TREE:
                 cgit_print_tree(ctx.qry.sha1, ctx.qry.path);
                 break;
         case CMD_COMMIT:
                 cgit_print_commit(ctx.qry.sha1);
                 break;
         case CMD_REFS:
                 cgit_print_refs();
                 break;
         case CMD_TAG:
                 cgit_print_tag(ctx.qry.sha1);
                 break;
         case CMD_DIFF:
                 cgit_print_diff(ctx.qry.sha1, ctx.qry.sha2, ctx.qry.path);
                 break;
         default:
                 cgit_print_error("Invalid request");
         }
         cgit_print_docend();
 }
 
 static void cgit_fill_cache(struct cacheitem *item, int use_cache)
 {
-        static char buf[PATH_MAX];
         int stdout2;
 
-        getcwd(buf, sizeof(buf));
         item->st.st_mtime = time(NULL);
 
         if (use_cache) {
                 stdout2 = chk_positive(dup(STDOUT_FILENO),
                                        "Preserving STDOUT");
                 chk_zero(close(STDOUT_FILENO), "Closing STDOUT");
                 chk_positive(dup2(item->fd, STDOUT_FILENO), "Dup2(cachefile)");
         }
 
         if (ctx.repo)
                 cgit_print_repo_page(item);
         else
                 cgit_print_repolist(item);
 
         if (use_cache) {
                 chk_zero(close(STDOUT_FILENO), "Close redirected STDOUT");
                 chk_positive(dup2(stdout2, STDOUT_FILENO),
                              "Restoring original STDOUT");
                 chk_zero(close(stdout2), "Closing temporary STDOUT");
         }
-
-        chdir(buf);
 }
 
 static void cgit_check_cache(struct cacheitem *item)
 {
         int i = 0;
 
  top:
         if (++i > ctx.cfg.max_lock_attempts) {
                 die("cgit_refresh_cache: unable to lock %s: %s",
                     item->name, strerror(errno));
         }
         if (!cache_exist(item)) {
                 if (!cache_lock(item)) {
                         sleep(1);
                         goto top;
                 }
                 if (!cache_exist(item)) {
                         cgit_fill_cache(item, 1);
                         cache_unlock(item);
                 } else {
                         cache_cancel_lock(item);
                 }
         } else if (cache_expired(item) && cache_lock(item)) {
                 if (cache_expired(item)) {
                         cgit_fill_cache(item, 1);
                         cache_unlock(item);
                 } else {
                         cache_cancel_lock(item);
                 }
         }
 }
 
 static void cgit_print_cache(struct cacheitem *item)
 {
         static char buf[4096];
         ssize_t i;
 
         int fd = open(item->name, O_RDONLY);
         if (fd<0)
                 die("Unable to open cached file %s", item->name);
 
         while((i=read(fd, buf, sizeof(buf))) > 0)
                 write(STDOUT_FILENO, buf, i);
 
         close(fd);
 }
 
 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);
                 }
         }
 }
 
 int main(int argc, const char **argv)
 {
         struct cacheitem item;
         const char *cgit_config_env = getenv("CGIT_CONFIG");
 
         cgit_prepare_context(&ctx);
         htmlfd = STDOUT_FILENO;
         item.st.st_mtime = time(NULL);
         cgit_repolist.length = 0;
         cgit_repolist.count = 0;
         cgit_repolist.repos = NULL;
 
         cgit_read_config(cgit_config_env ? cgit_config_env : CGIT_CONFIG,
                          cgit_global_config_cb);
         if (getenv("SCRIPT_NAME"))
diff --git a/ui-shared.c b/ui-shared.c
index b9f487a..cc1ab8b 100644
--- a/ui-shared.c
+++ b/ui-shared.c
@@ -383,188 +383,188 @@ void cgit_print_docstart(char *title, struct cacheitem *item)
         html("<body>\n");
 }
 
 void cgit_print_docend()
 {
         html("</td>\n</tr>\n</table>\n</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))
                 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);
         }
 }
 
 void cgit_print_pageheader(char *title, int show_search)
 {
         static const char *default_info = "This is cgit, a fast webinterface for git repositories";
         int header = 0;
         char *url;
 
         html("<table id='layout' summary=''>\n");
         html("<tr><td id='sidebar'>\n");
         html("<table class='sidebar' cellspacing='0' summary=''>\n");
         html("<tr><td class='sidebar'>\n<a href='");
         html_attr(cgit_rooturl());
         htmlf("'><img src='%s' alt='cgit'/></a>\n",
               ctx.cfg.logo);
         html("</td></tr>\n<tr><td class='sidebar'>\n");
-        if (ctx.qry.repo) {
+        if (ctx.repo) {
                 html("<h1 class='first'>");
                 html_txt(strrpart(ctx.repo->name, 20));
                 html("</h1>\n");
                 html_txt(ctx.repo->desc);
                 if (ctx.repo->owner) {
                         html("<h1>owner</h1>\n");
                         html_txt(ctx.repo->owner);
                 }
                 html("<h1>navigate</h1>\n");
                 reporevlink(NULL, "summary", NULL, "menu", ctx.qry.head,
                             NULL, NULL);
                 cgit_log_link("log", NULL, "menu", ctx.qry.head, NULL, NULL,
                               0, NULL, NULL);
                 cgit_tree_link("tree", NULL, "menu", ctx.qry.head,
                                ctx.qry.sha1, NULL);
                 cgit_commit_link("commit", NULL, "menu", ctx.qry.head,
                               ctx.qry.sha1);
                 cgit_diff_link("diff", NULL, "menu", ctx.qry.head,
                                ctx.qry.sha1, ctx.qry.sha2, NULL);
                 cgit_patch_link("patch", NULL, "menu", ctx.qry.head,
                                 ctx.qry.sha1);
 
                 for_each_ref(print_archive_ref, &header);
 
                 if (ctx.repo->clone_url || ctx.cfg.clone_prefix) {
                         html("<h1>clone</h1>\n");
                         if (ctx.repo->clone_url)
                                 url = ctx.repo->clone_url;
                         else
                                 url = fmt("%s%s", ctx.cfg.clone_prefix,
                                           ctx.repo->url);
                         html("<a class='menu' href='");
                         html_attr(url);
                         html("' title='");
                         html_attr(url);
                         html("'>\n");
                         html_txt(strrpart(url, 20));
                         html("</a>\n");
                 }
 
                 html("<h1>branch</h1>\n");
                 html("<form method='get' action=''>\n");
                 add_hidden_formfields(0, 1, ctx.qry.page);
         //      html("<table summary='branch selector' class='grid'><tr><td id='branch-dropdown-cell'>");
                 html("<select name='h' onchange='this.form.submit();'>\n");
                 for_each_branch_ref(print_branch_option, ctx.qry.head);
                 html("</select>\n");
         //      html("</td><td>");
                 html("<noscript><input type='submit' id='switch-btn' value='switch'/></noscript>\n");
         //      html("</td></tr></table>");
                 html("</form>\n");
 
                 html("<h1>search</h1>\n");
                 html("<form 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' name='q' value='");
                 html_attr(ctx.qry.search);
                 html("'/>\n");
                 html("</form>\n");
         } else {
                 if (!ctx.cfg.index_info || html_include(ctx.cfg.index_info))
                         html(default_info);
         }
 
         html("</td></tr></table></td>\n");
 
         html("<td id='content'>\n");
 }
 
 
 void cgit_print_snapshot_start(const char *mimetype, const char *filename,
                                struct cacheitem *item)
 {
         htmlf("Content-Type: %s\n", mimetype);
         htmlf("Content-Disposition: inline; filename=\"%s\"\n", filename);
         htmlf("Last-Modified: %s\n", http_date(item->st.st_mtime));
         htmlf("Expires: %s\n", http_date(item->st.st_mtime +
                                          ttl_seconds(item->ttl)));
         html("\n");
 }
 
 /* vim:set sw=8: */