Add support for 'project-list' option

This option specifies the location of a projectlist file as used by
gitweb - when 'scan-tree' is later specified, only the projects listed in
the projectlist file will be added.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>

5 files changed, 70 insertions, 8 deletions

diff --git a/cgit.c b/cgit.c
index c263872..2364d1c 100644
--- a/cgit.c
+++ b/cgit.c
@@ -136,99 +136,104 @@ void config_cb(const char *name, const char *value)
         else if (!strcmp(name, "enable-filter-overrides"))
                 ctx.cfg.enable_filter_overrides = atoi(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, "enable-remote-branches"))
                 ctx.cfg.enable_remote_branches = atoi(value);
         else if (!strcmp(name, "enable-subject-links"))
                 ctx.cfg.enable_subject_links = atoi(value);
         else if (!strcmp(name, "enable-tree-linenumbers"))
                 ctx.cfg.enable_tree_linenumbers = atoi(value);
         else if (!strcmp(name, "max-stats"))
                 ctx.cfg.max_stats = cgit_find_stats_period(value, NULL);
         else if (!strcmp(name, "cache-size"))
                 ctx.cfg.cache_size = atoi(value);
         else if (!strcmp(name, "cache-root"))
                 ctx.cfg.cache_root = xstrdup(expand_macros(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-scanrc-ttl"))
                 ctx.cfg.cache_scanrc_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, "about-filter"))
                 ctx.cfg.about_filter = new_filter(value, 0);
         else if (!strcmp(name, "commit-filter"))
                 ctx.cfg.commit_filter = new_filter(value, 0);
         else if (!strcmp(name, "embedded"))
                 ctx.cfg.embedded = atoi(value);
         else if (!strcmp(name, "max-atom-items"))
                 ctx.cfg.max_atom_items = 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-blob-size"))
                 ctx.cfg.max_blob_size = 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, "project-list"))
+                ctx.cfg.project_list = xstrdup(expand_macros(value));
         else if (!strcmp(name, "scan-path"))
                 if (!ctx.cfg.nocache && ctx.cfg.cache_size)
                         process_cached_repolist(expand_macros(value));
+                else if (ctx.cfg.project_list)
+                        scan_projects(expand_macros(value),
+                                      ctx.cfg.project_list, repo_config);
                 else
                         scan_tree(expand_macros(value), repo_config);
         else if (!strcmp(name, "source-filter"))
                 ctx.cfg.source_filter = new_filter(value, 1);
         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, "side-by-side-diffs"))
                 ctx.cfg.ssdiff = 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, "local-time"))
                 ctx.cfg.local_time = atoi(value);
         else if (!prefixcmp(name, "mimetype."))
                 add_mimetype(name + 9, value);
         else if (!strcmp(name, "include"))
                 parse_configfile(expand_macros(value), config_cb);
 }
 
 static void querystring_cb(const char *name, const char *value)
 {
         if (!value)
                 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")) {
                 if (*value == '/')
                         value++;
                 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")) {
@@ -250,96 +255,97 @@ static void querystring_cb(const char *name, const char *value)
                 ctx.qry.mimetype = xstrdup(value);
         } else if (!strcmp(name, "s")){
                 ctx.qry.sort = xstrdup(value);
         } else if (!strcmp(name, "showmsg")) {
                 ctx.qry.showmsg = atoi(value);
         } else if (!strcmp(name, "period")) {
                 ctx.qry.period = xstrdup(value);
         } else if (!strcmp(name, "ss")) {
                 ctx.qry.ssdiff = atoi(value);
         } else if (!strcmp(name, "all")) {
                 ctx.qry.show_all = atoi(value);
         } else if (!strcmp(name, "context")) {
                 ctx.qry.context = atoi(value);
         } else if (!strcmp(name, "ignorews")) {
                 ctx.qry.ignorews = atoi(value);
         }
 }
 
 char *xstrdupn(const char *str)
 {
         return (str ? xstrdup(str) : NULL);
 }
 
 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_scanrc_ttl = 15;
         ctx->cfg.cache_static_ttl = -1;
         ctx->cfg.css = "/cgit.css";
         ctx->cfg.logo = "/cgit.png";
         ctx->cfg.local_time = 0;
         ctx->cfg.enable_tree_linenumbers = 1;
         ctx->cfg.max_repo_count = 50;
         ctx->cfg.max_commit_count = 50;
         ctx->cfg.max_lock_attempts = 5;
         ctx->cfg.max_msg_len = 80;
         ctx->cfg.max_repodesc_len = 80;
         ctx->cfg.max_blob_size = 0;
         ctx->cfg.max_stats = 0;
         ctx->cfg.module_link = "./?repo=%s&page=commit&id=%s";
+        ctx->cfg.project_list = NULL;
         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->cfg.section = "";
         ctx->cfg.summary_branches = 10;
         ctx->cfg.summary_log = 10;
         ctx->cfg.summary_tags = 10;
         ctx->cfg.max_atom_items = 10;
         ctx->cfg.ssdiff = 0;
         ctx->env.cgit_config = xstrdupn(getenv("CGIT_CONFIG"));
         ctx->env.http_host = xstrdupn(getenv("HTTP_HOST"));
         ctx->env.https = xstrdupn(getenv("HTTPS"));
         ctx->env.no_http = xstrdupn(getenv("NO_HTTP"));
         ctx->env.path_info = xstrdupn(getenv("PATH_INFO"));
         ctx->env.query_string = xstrdupn(getenv("QUERY_STRING"));
         ctx->env.request_method = xstrdupn(getenv("REQUEST_METHOD"));
         ctx->env.script_name = xstrdupn(getenv("SCRIPT_NAME"));
         ctx->env.server_name = xstrdupn(getenv("SERVER_NAME"));
         ctx->env.server_port = xstrdupn(getenv("SERVER_PORT"));
         ctx->page.mimetype = "text/html";
         ctx->page.charset = PAGE_ENCODING;
         ctx->page.filename = NULL;
         ctx->page.size = 0;
         ctx->page.modified = time(NULL);
         ctx->page.expires = ctx->page.modified;
         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;
 
@@ -529,121 +535,132 @@ void print_repo(FILE *f, struct cgit_repo *repo)
         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);
+        if (ctx.cfg.project_list)
+                scan_projects(path, ctx.cfg.project_list, repo_config);
+        else
+                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;
+        unsigned long hash;
 
-        cached_rc = xstrdup(fmt("%s/rc-%8x", ctx.cfg.cache_root,
-                hash_str(path)));
+        hash = hash_str(path);
+        if (ctx.cfg.project_list)
+                hash += hash_str(ctx.cfg.project_list);
+        cached_rc = xstrdup(fmt("%s/rc-%8x", ctx.cfg.cache_root, hash));
 
         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);
+                if (generate_cached_repolist(path, cached_rc)) {
+                        if (ctx.cfg.project_list)
+                                scan_projects(path, ctx.cfg.project_list,
+                                              repo_config);
+                        else
+                                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;
                 }
diff --git a/cgit.h b/cgit.h
index e9e2718..4591f8c 100644
--- a/cgit.h
+++ b/cgit.h
@@ -121,96 +121,97 @@ struct refinfo {
 
 struct reflist {
         struct refinfo **refs;
         int alloc;
         int count;
 };
 
 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;
         char *period;
         int   ofs;
         int nohead;
         char *sort;
         int showmsg;
         int ssdiff;
         int show_all;
         int context;
         int ignorews;
         char *vpath;
 };
 
 struct cgit_config {
         char *agefile;
         char *cache_root;
         char *clone_prefix;
         char *css;
         char *favicon;
         char *footer;
         char *head_include;
         char *header;
         char *index_header;
         char *index_info;
         char *logo;
         char *logo_link;
         char *module_link;
+        char *project_list;
         char *robots;
         char *root_title;
         char *root_desc;
         char *root_readme;
         char *script_name;
         char *section;
         char *virtual_root;
         int cache_size;
         int cache_dynamic_ttl;
         int cache_max_create_time;
         int cache_repo_ttl;
         int cache_root_ttl;
         int cache_scanrc_ttl;
         int cache_static_ttl;
         int embedded;
         int enable_filter_overrides;
         int enable_index_links;
         int enable_log_filecount;
         int enable_log_linecount;
         int enable_remote_branches;
         int enable_subject_links;
         int enable_tree_linenumbers;
         int local_time;
         int max_atom_items;
         int max_repo_count;
         int max_commit_count;
         int max_lock_attempts;
         int max_msg_len;
         int max_repodesc_len;
         int max_blob_size;
         int max_stats;
         int nocache;
         int noplainemail;
         int noheader;
         int renamelimit;
         int snapshots;
         int summary_branches;
         int summary_log;
         int summary_tags;
         int ssdiff;
         struct string_list mimetypes;
         struct cgit_filter *about_filter;
         struct cgit_filter *commit_filter;
         struct cgit_filter *source_filter;
 };
 
 struct cgit_page {
         time_t modified;
diff --git a/cgitrc.5.txt b/cgitrc.5.txt
index a853522..ec004d4 100644
--- a/cgitrc.5.txt
+++ b/cgitrc.5.txt
@@ -179,126 +179,134 @@ max-atom-items::
 max-commit-count::
         Specifies the number of entries to list per page in "log" view. Default
         value: "50".
 
 max-message-length::
         Specifies the maximum number of commit message characters to display in
         "log" view. Default value: "80".
 
 max-repo-count::
                 Specifies the number of entries to list per page on therepository
         index page. Default value: "50".
 
 max-repodesc-length::
         Specifies the maximum number of repo description characters to display
         on the repository index page. Default value: "80".
 
 max-blob-size::
         Specifies the maximum size of a blob to display HTML for in KBytes.
         Default value: "0" (limit disabled).
 
 max-stats::
         Set the default maximum statistics period. Valid values are "week",
         "month", "quarter" and "year". If unspecified, statistics are
         disabled. Default value: none. See also: "repo.max-stats".
 
 mimetype.<ext>::
         Set the mimetype for the specified filename extension. This is used
         by the `plain` command when returning blob content.
 
 module-link::
         Text which will be used as the formatstring for a hyperlink when a
         submodule is printed in a directory listing. The arguments for the
         formatstring are the path and SHA1 of the submodule commit. Default
         value: "./?repo=%s&page=commit&id=%s"
 
 nocache::
         If set to the value "1" caching will be disabled. This settings is
         deprecated, and will not be honored starting with cgit-1.0. Default
         value: "0".
 
 noplainemail::
         If set to "1" showing full author email adresses will be disabled.
         Default value: "0".
 
 noheader::
         Flag which, when set to "1", will make cgit omit the standard header
         on all pages. Default value: none. See also: "embedded".
 
+project-list::
+        A list of subdirectories inside of scan-path, relative to it, that
+        should loaded as git repositories. This must be defined prior to
+        scan-path. Default value: none. See also: scan-path.
+
 renamelimit::
         Maximum number of files to consider when detecting renames. The value
          "-1" uses the compiletime value in git (for further info, look at
           `man git-diff`). Default value: "-1".
 
 repo.group::
         Legacy alias for "section". This option is deprecated and will not be
         supported in cgit-1.0.
 
 robots::
         Text used as content for the "robots" meta-tag. Default value:
         "index, nofollow".
 
 root-desc::
         Text printed below the heading on the repository index page. Default
         value: "a fast webinterface for the git dscm".
 
 root-readme::
         The content of the file specified with this option will be included
         verbatim below the "about" link on the repository index page. Default
         value: none.
 
 root-title::
         Text printed as heading on the repository index page. Default value:
         "Git Repository Browser".
 
 scan-path::
         A path which will be scanned for repositories. If caching is enabled,
         the result will be cached as a cgitrc include-file in the cache
-        directory. Default value: none. See also: cache-scanrc-ttl.
+        directory. If project-list has been defined prior to scan-path,
+        scan-path loads only the directories listed in the file pointed to by
+        project-list. Default value: none. See also: cache-scanrc-ttl,
+        project-list.
 
 section::
         The name of the current repository section - all repositories defined
         after this option will inherit the current section name. Default value:
         none.
 
 side-by-side-diffs::
         If set to "1" shows side-by-side diffs instead of unidiffs per
         default. Default value: "0".
 
 snapshots::
         Text which specifies the default set of snapshot formats generated by
         cgit. The value is a space-separated list of zero or more of the
         values "tar", "tar.gz", "tar.bz2" and "zip". Default value: none.
 
 source-filter::
         Specifies a command which will be invoked to format plaintext blobs
         in the tree view. The command will get the blob content on its STDIN
         and the name of the blob as its only command line argument. The STDOUT
         from the command will be included verbatim as the blob contents, i.e.
         this can be used to implement e.g. syntax highlighting. Default value:
         none.
 
 summary-branches::
         Specifies the number of branches to display in the repository "summary"
         view. Default value: "10".
 
 summary-log::
         Specifies the number of log entries to display in the repository
         "summary" view. Default value: "10".
 
 summary-tags::
         Specifies the number of tags to display in the repository "summary"
         view. Default value: "10".
 
 virtual-root::
         Url which, if specified, will be used as root for all cgit links. It
         will also cause cgit to generate 'virtual urls', i.e. urls like
         '/cgit/tree/README' as opposed to '?r=cgit&p=tree&path=README'. Default
         value: none.
         NOTE: cgit has recently learned how to use PATH_INFO to achieve the
         same kind of virtual urls, so this option will probably be deprecated.
 
 REPOSITORY SETTINGS
 -------------------
 repo.about-filter::
         Override the default about-filter. Default value: none. See also:
         "enable-filter-overrides".
diff --git a/scan-tree.c b/scan-tree.c
index 1e18f3c..9bf9b38 100644
--- a/scan-tree.c
+++ b/scan-tree.c
@@ -1,48 +1,57 @@
+/* scan-tree.c
+ * 
+ * Copyright (C) 2008-2009 Lars Hjemli
+ * Copyright (C) 2010 Jason A. Donenfeld <Jason@zx2c4.com>
+ *
+ * Licensed under GNU General Public License v2
+ *   (see COPYING for full license text)
+ */
+
 #include "cgit.h"
 #include "configfile.h"
 #include "html.h"
 
 #define MAX_PATH 4096
 
 /* return 1 if path contains a objects/ directory and a HEAD file */
 static int is_git_dir(const char *path)
 {
         struct stat st;
         static char buf[MAX_PATH];
 
         if (snprintf(buf, MAX_PATH, "%s/objects", path) >= MAX_PATH) {
                 fprintf(stderr, "Insanely long path: %s\n", path);
                 return 0;
         }
         if (stat(buf, &st)) {
                 if (errno != ENOENT)
                         fprintf(stderr, "Error checking path %s: %s (%d)\n",
                                 path, strerror(errno), errno);
                 return 0;
         }
         if (!S_ISDIR(st.st_mode))
                 return 0;
 
         sprintf(buf, "%s/HEAD", path);
         if (stat(buf, &st)) {
                 if (errno != ENOENT)
                         fprintf(stderr, "Error checking path %s: %s (%d)\n",
                                 path, strerror(errno), errno);
                 return 0;
         }
         if (!S_ISREG(st.st_mode))
                 return 0;
 
         return 1;
 }
 
 struct cgit_repo *repo;
 repo_config_fn config_fn;
 
 static void repo_config(const char *name, const char *value)
 {
         config_fn(repo, name, value);
 }
 
 static void add_repo(const char *base, const char *path, repo_config_fn fn)
 {
@@ -97,52 +106,80 @@ static void add_repo(const char *base, const char *path, repo_config_fn fn)
 static void scan_path(const char *base, const char *path, repo_config_fn fn)
 {
         DIR *dir;
         struct dirent *ent;
         char *buf;
         struct stat st;
 
         if (is_git_dir(path)) {
                 add_repo(base, path, fn);
                 return;
         }
         if (is_git_dir(fmt("%s/.git", path))) {
                 add_repo(base, fmt("%s/.git", path), fn);
                 return;
         }
         dir = opendir(path);
         if (!dir) {
                 fprintf(stderr, "Error opening directory %s: %s (%d)\n",
                         path, strerror(errno), errno);
                 return;
         }
         while((ent = readdir(dir)) != NULL) {
                 if (ent->d_name[0] == '.') {
                         if (ent->d_name[1] == '\0')
                                 continue;
                         if (ent->d_name[1] == '.' && ent->d_name[2] == '\0')
                                 continue;
                 }
                 buf = malloc(strlen(path) + strlen(ent->d_name) + 2);
                 if (!buf) {
                         fprintf(stderr, "Alloc error on %s: %s (%d)\n",
                                 path, strerror(errno), errno);
                         exit(1);
                 }
                 sprintf(buf, "%s/%s", path, ent->d_name);
                 if (stat(buf, &st)) {
                         fprintf(stderr, "Error checking path %s: %s (%d)\n",
                                 buf, strerror(errno), errno);
                         free(buf);
                         continue;
                 }
                 if (S_ISDIR(st.st_mode))
                         scan_path(base, buf, fn);
                 free(buf);
         }
         closedir(dir);
 }
 
+#define lastc(s) s[strlen(s) - 1]
+
+void scan_projects(const char *path, const char *projectsfile, repo_config_fn fn)
+{
+        char line[MAX_PATH * 2], *z;
+        FILE *projects;
+        int err;
+        
+        projects = fopen(projectsfile, "r");
+        if (!projects) {
+                fprintf(stderr, "Error opening projectsfile %s: %s (%d)\n",
+                        projectsfile, strerror(errno), errno);
+        }
+        while (fgets(line, sizeof(line), projects) != NULL) {
+                for (z = &lastc(line);
+                     strlen(line) && strchr("\n\r", *z);
+                     z = &lastc(line))
+                        *z = '\0';
+                if (strlen(line))
+                        scan_path(path, fmt("%s/%s", path, line), fn);
+        }
+        if ((err = ferror(projects))) {
+                fprintf(stderr, "Error reading from projectsfile %s: %s (%d)\n",
+                        projectsfile, strerror(err), err);
+        }
+        fclose(projects);
+}
+
 void scan_tree(const char *path, repo_config_fn fn)
 {
         scan_path(path, path, fn);
 }
diff --git a/scan-tree.h b/scan-tree.h
index 11539f4..1afbd4b 100644
--- a/scan-tree.h
+++ b/scan-tree.h
@@ -1,3 +1,2 @@
-
-
+extern void scan_projects(const char *path, const char *projectsfile, repo_config_fn fn);
 extern void scan_tree(const char *path, repo_config_fn fn);