Avoid trailing slash in virtual-root

When setting virtual-root from cgitrc, care is taken to avoid trailing
slashes. But when no virtual-root setting is specified, SCRIPT_FILE
from the web server is used without similar checks. This patch fixes the
inconsistency, which could lead to double-slashes in generated links.

Noticed-by: Wouter Van Hemel <wouter@duodecim.org>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/cgit.c b/cgit.c
index ad62d10..af9832f 100644
--- a/cgit.c
+++ b/cgit.c
@@ -298,421 +298,422 @@ static void prepare_context(struct cgit_context *ctx)
         ctx->page.etag = NULL;
         memset(&ctx->cfg.mimetypes, 0, sizeof(struct string_list));
         if (ctx->env.script_name)
                 ctx->cfg.script_name = ctx->env.script_name;
         if (ctx->env.query_string)
                 ctx->qry.raw = ctx->env.query_string;
         if (!ctx->env.cgit_config)
                 ctx->env.cgit_config = CGIT_CONFIG;
 }
 
 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)
                 ref = info.req_ref;
         else
                 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.nohead = 1;
                 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;
                 ctx->page.status = 404;
                 ctx->page.statusmsg = "not found";
                 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";
                 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();
 }
 
 int cmp_repos(const void *a, const void *b)
 {
         const struct cgit_repo *ra = a, *rb = b;
         return strcmp(ra->url, rb->url);
 }
 
 char *build_snapshot_setting(int bitmap)
 {
         const struct cgit_snapshot_format *f;
         char *result = xstrdup("");
         char *tmp;
         int len;
 
         for (f = cgit_snapshot_formats; f->suffix; f++) {
                 if (f->bit & bitmap) {
                         tmp = result;
                         result = xstrdup(fmt("%s%s ", tmp, f->suffix));
                         free(tmp);
                 }
         }
         len = strlen(result);
         if (len)
                 result[len - 1] = '\0';
         return result;
 }
 
 char *get_first_line(char *txt)
 {
         char *t = xstrdup(txt);
         char *p = strchr(t, '\n');
         if (p)
                 *p = '\0';
         return t;
 }
 
 void print_repo(FILE *f, struct cgit_repo *repo)
 {
         fprintf(f, "repo.url=%s\n", repo->url);
         fprintf(f, "repo.name=%s\n", repo->name);
         fprintf(f, "repo.path=%s\n", repo->path);
         if (repo->owner)
                 fprintf(f, "repo.owner=%s\n", repo->owner);
         if (repo->desc) {
                 char *tmp = get_first_line(repo->desc);
                 fprintf(f, "repo.desc=%s\n", tmp);
                 free(tmp);
         }
         if (repo->readme)
                 fprintf(f, "repo.readme=%s\n", repo->readme);
         if (repo->defbranch)
                 fprintf(f, "repo.defbranch=%s\n", repo->defbranch);
         if (repo->module_link)
                 fprintf(f, "repo.module-link=%s\n", repo->module_link);
         if (repo->section)
                 fprintf(f, "repo.section=%s\n", repo->section);
         if (repo->clone_url)
                 fprintf(f, "repo.clone-url=%s\n", repo->clone_url);
         fprintf(f, "repo.enable-log-filecount=%d\n",
                 repo->enable_log_filecount);
         fprintf(f, "repo.enable-log-linecount=%d\n",
                 repo->enable_log_linecount);
         if (repo->about_filter && repo->about_filter != ctx.cfg.about_filter)
                 fprintf(f, "repo.about-filter=%s\n", repo->about_filter->cmd);
         if (repo->commit_filter && repo->commit_filter != ctx.cfg.commit_filter)
                 fprintf(f, "repo.commit-filter=%s\n", repo->commit_filter->cmd);
         if (repo->source_filter && repo->source_filter != ctx.cfg.source_filter)
                 fprintf(f, "repo.source-filter=%s\n", repo->source_filter->cmd);
         if (repo->snapshots != ctx.cfg.snapshots) {
                 char *tmp = build_snapshot_setting(repo->snapshots);
                 fprintf(f, "repo.snapshots=%s\n", tmp);
                 free(tmp);
         }
         if (repo->max_stats != ctx.cfg.max_stats)
                 fprintf(f, "repo.max-stats=%s\n",
                         cgit_find_stats_periodname(repo->max_stats));
         fprintf(f, "\n");
 }
 
 void print_repolist(FILE *f, struct cgit_repolist *list, int start)
 {
         int i;
 
         for(i = start; i < list->count; i++)
                 print_repo(f, &list->repos[i]);
 }
 
 /* Scan 'path' for git repositories, save the resulting repolist in 'cached_rc'
  * and return 0 on success.
  */
 static int generate_cached_repolist(const char *path, const char *cached_rc)
 {
         char *locked_rc;
         int idx;
         FILE *f;
 
         locked_rc = xstrdup(fmt("%s.lock", cached_rc));
         f = fopen(locked_rc, "wx");
         if (!f) {
                 /* Inform about the error unless the lockfile already existed,
                  * since that only means we've got concurrent requests.
                  */
                 if (errno != EEXIST)
                         fprintf(stderr, "[cgit] Error opening %s: %s (%d)\n",
                                 locked_rc, strerror(errno), errno);
                 return errno;
         }
         idx = cgit_repolist.count;
         scan_tree(path, repo_config);
         print_repolist(f, &cgit_repolist, idx);
         if (rename(locked_rc, cached_rc))
                 fprintf(stderr, "[cgit] Error renaming %s to %s: %s (%d)\n",
                         locked_rc, cached_rc, strerror(errno), errno);
         fclose(f);
         return 0;
 }
 
 static void process_cached_repolist(const char *path)
 {
         struct stat st;
         char *cached_rc;
         time_t age;
 
         cached_rc = xstrdup(fmt("%s/rc-%8x", ctx.cfg.cache_root,
                 hash_str(path)));
 
         if (stat(cached_rc, &st)) {
                 /* Nothing is cached, we need to scan without forking. And
                  * if we fail to generate a cached repolist, we need to
                  * invoke scan_tree manually.
                  */
                 if (generate_cached_repolist(path, cached_rc))
                         scan_tree(path, repo_config);
                 return;
         }
 
         parse_configfile(cached_rc, config_cb);
 
         /* If the cached configfile hasn't expired, lets exit now */
         age = time(NULL) - st.st_mtime;
         if (age <= (ctx.cfg.cache_scanrc_ttl * 60))
                 return;
 
         /* The cached repolist has been parsed, but it was old. So lets
          * rescan the specified path and generate a new cached repolist
          * in a child-process to avoid latency for the current request.
          */
         if (fork())
                 return;
 
         exit(generate_cached_repolist(path, cached_rc));
 }
 
 static void cgit_parse_args(int argc, const char **argv)
 {
         int i;
         int scan = 0;
 
         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 (!strcmp(argv[i], "--nohttp")) {
                         ctx.env.no_http = "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);
                 }
                 if (!strncmp(argv[i], "--scan-tree=", 12) ||
                     !strncmp(argv[i], "--scan-path=", 12)) {
                         /* HACK: the global snapshot bitmask defines the
                          * set of allowed snapshot formats, but the config
                          * file hasn't been parsed yet so the mask is
                          * currently 0. By setting all bits high before
                          * scanning we make sure that any in-repo cgitrc
                          * snapshot setting is respected by scan_tree().
                          * BTW: we assume that there'll never be more than
                          * 255 different snapshot formats supported by cgit...
                          */
                         ctx.cfg.snapshots = 0xFF;
                         scan++;
                         scan_tree(argv[i] + 12, repo_config);
                 }
         }
         if (scan) {
                 qsort(cgit_repolist.repos, cgit_repolist.count,
                         sizeof(struct cgit_repo), cmp_repos);
                 print_repolist(stdout, &cgit_repolist, 0);
                 exit(0);
         }
 }
 
 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 *path;
         char *qry;
         int err, ttl;
 
         prepare_context(&ctx);
         cgit_repolist.length = 0;
         cgit_repolist.count = 0;
         cgit_repolist.repos = NULL;
 
         cgit_parse_args(argc, argv);
         parse_configfile(ctx.env.cgit_config, config_cb);
         ctx.repo = NULL;
         http_parse_querystring(ctx.qry.raw, querystring_cb);
 
         /* If virtual-root isn't specified in cgitrc, lets pretend
-         * that virtual-root equals SCRIPT_NAME.
+         * that virtual-root equals SCRIPT_NAME, minus any possibly
+         * trailing slashes.
          */
         if (!ctx.cfg.virtual_root)
-                ctx.cfg.virtual_root = ctx.cfg.script_name;
+                ctx.cfg.virtual_root = trim_end(ctx.cfg.script_name, '/');
 
         /* If no url parameter is specified on the querystring, lets
          * 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).
          */
         path = ctx.env.path_info;
         if (!ctx.qry.url && 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 = xstrdup(ctx.qry.url);
                 cgit_parse_url(ctx.qry.url);
         }
 
         ttl = calc_ttl();
         ctx.page.expires += ttl*60;
         if (ctx.env.request_method && !strcmp(ctx.env.request_method, "HEAD"))
                 ctx.cfg.nocache = 1;
         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;
 }