Add argument parsing + switch for uncached operation

This adds support for the following options to cgit:
  --root=<path>
  --cache=<path>
  --nocache
  --query=<querystring>
  --repo=<reponame>
  --page=<pagename>
  --head=<branchname>
  --sha1=<sha1>
  --ofs=<number>

On startup, /etc/cgitrc is parsed, followed by argument parsing and
finally querystring parsing.

If --nocache is specified (or set in /etc/gitrc), caching is disabled and
cgit instead generates pages to stdout.

The combined effect of these two changes makes testing/debugging a lot
less painfull.

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

3 files changed, 51 insertions, 3 deletions

diff --git a/cgit.c b/cgit.c
index 37cdb83..9dbc608 100644
--- a/cgit.c
+++ b/cgit.c
@@ -1,110 +1,154 @@
 /* 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"
 
 const char cgit_version[] = CGIT_VERSION;
 
 static void cgit_print_repo_page(struct cacheitem *item)
 {
         if (chdir(fmt("%s/%s", cgit_root, cgit_query_repo)) || 
             cgit_read_config("info/cgit", cgit_repo_config_cb)) {
                 char *title = fmt("%s - %s", cgit_root_title, "Bad request");
                 cgit_print_docstart(title, item);
                 cgit_print_pageheader(title);
                 cgit_print_error(fmt("Unable to scan repository: %s",
                                      strerror(errno)));
                 cgit_print_docend();
                 return;
         }
         setenv("GIT_DIR", fmt("%s/%s", cgit_root, cgit_query_repo), 1);
         char *title = fmt("%s - %s", cgit_repo_name, cgit_repo_desc);
         cgit_print_docstart(title, item);
         cgit_print_pageheader(title);
         if (!cgit_query_page) {
                 cgit_print_summary();
         } else if (!strcmp(cgit_query_page, "log")) {
                 cgit_print_log(cgit_query_head, cgit_query_ofs, 100);
         } else if (!strcmp(cgit_query_page, "tree")) {
                 cgit_print_tree(cgit_query_sha1);
         } else if (!strcmp(cgit_query_page, "commit")) {
                 cgit_print_commit(cgit_query_sha1);
         } else if (!strcmp(cgit_query_page, "view")) {
                 cgit_print_view(cgit_query_sha1);
         }
         cgit_print_docend();
 }
 
 static void cgit_fill_cache(struct cacheitem *item)
 {
         htmlfd = item->fd;
         item->st.st_mtime = time(NULL);
         if (cgit_query_repo)
                 cgit_print_repo_page(item);
         else
                 cgit_print_repolist(item);
 }
 
 static void cgit_check_cache(struct cacheitem *item)
 {
         int i = 0;
 
         cache_prepare(item);
  top:
         if (++i > cgit_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);
                         cache_unlock(item);
                 } else {
                         cache_cancel_lock(item);
                 }
         } else if (cache_expired(item) && cache_lock(item)) {
                 if (cache_expired(item)) {
                         cgit_fill_cache(item);
                         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], "--root=", 7)) {
+                        cgit_root = xstrdup(argv[i]+7);
+                }
+                if (!strncmp(argv[i], "--cache=", 8)) {
+                        cgit_cache_root = xstrdup(argv[i]+8);
+                }
+                if (!strcmp(argv[i], "--nocache")) {
+                        cgit_nocache = 1;
+                }
+                if (!strncmp(argv[i], "--query=", 8)) {
+                        cgit_querystring = xstrdup(argv[i]+8);
+                }
+                if (!strncmp(argv[i], "--repo=", 7)) {
+                        cgit_query_repo = xstrdup(argv[i]+7);
+                }
+                if (!strncmp(argv[i], "--page=", 7)) {
+                        cgit_query_page = xstrdup(argv[i]+7);
+                }
+                if (!strncmp(argv[i], "--head=", 7)) {
+                        cgit_query_head = xstrdup(argv[i]+7);
+                        cgit_query_has_symref = 1;
+                }
+                if (!strncmp(argv[i], "--sha1=", 7)) {
+                        cgit_query_sha1 = xstrdup(argv[i]+7);
+                        cgit_query_has_sha1 = 1;
+                }
+                if (!strncmp(argv[i], "--ofs=", 6)) {
+                        cgit_query_ofs = atoi(argv[i]+6);
+                }
+        }
+}
+
 int main(int argc, const char **argv)
 {
         struct cacheitem item;
 
         cgit_read_config("/etc/cgitrc", cgit_global_config_cb);
-        cgit_querystring = xstrdup(getenv("QUERY_STRING"));
+        if (getenv("QUERY_STRING"))
+                cgit_querystring = xstrdup(getenv("QUERY_STRING"));
+        cgit_parse_args(argc, argv);
         cgit_parse_query(cgit_querystring, cgit_querystring_cb);
 
-        cgit_check_cache(&item);
-        cgit_print_cache(&item);
+        if (cgit_nocache) {
+                item.fd = STDOUT_FILENO;
+                cgit_fill_cache(&item);
+        } else {
+                cgit_check_cache(&item);
+                cgit_print_cache(&item);
+        }
         return 0;
 }
diff --git a/cgit.h b/cgit.h
index a54f2b5..b6b60c6 100644
--- a/cgit.h
+++ b/cgit.h
@@ -1,100 +1,101 @@
 #ifndef CGIT_H
 #define CGIT_H
 
 #include "git.h"
 #include <openssl/sha.h>
 #include <ctype.h>
 #include <sched.h>
 
 typedef void (*configfn)(const char *name, const char *value);
 
 struct cacheitem {
         char *name;
         struct stat st;
         int ttl;
         int fd;
 };
 
 struct commitinfo {
         struct commit *commit;
         char *author;
         char *committer;
         char *subject;
         char *msg;
 };
 
 extern const char cgit_version[];
 
 extern char *cgit_root;
 extern char *cgit_root_title;
 extern char *cgit_css;
 extern char *cgit_logo;
 extern char *cgit_logo_link;
 extern char *cgit_virtual_root;
 extern char *cgit_cache_root;
 
+extern int cgit_nocache;
 extern int cgit_max_lock_attempts;
 extern int cgit_cache_root_ttl;
 extern int cgit_cache_repo_ttl;
 extern int cgit_cache_dynamic_ttl;
 extern int cgit_cache_static_ttl;
 extern int cgit_cache_max_create_time;
 
 extern char *cgit_repo_name;
 extern char *cgit_repo_desc;
 extern char *cgit_repo_owner;
 
 extern int cgit_query_has_symref;
 extern int cgit_query_has_sha1;
 
 extern char *cgit_querystring;
 extern char *cgit_query_repo;
 extern char *cgit_query_page;
 extern char *cgit_query_head;
 extern char *cgit_query_sha1;
 extern int   cgit_query_ofs;
 
 extern int htmlfd;
 
 extern void cgit_global_config_cb(const char *name, const char *value);
 extern void cgit_repo_config_cb(const char *name, const char *value);
 extern void cgit_querystring_cb(const char *name, const char *value);
 
 extern char *fmt(const char *format,...);
 
 extern void html(const char *txt);
 extern void htmlf(const char *format,...);
 extern void html_txt(char *txt);
 extern void html_attr(char *txt);
 extern void html_link_open(char *url, char *title, char *class);
 extern void html_link_close(void);
 
 extern int cgit_read_config(const char *filename, configfn fn);
 extern int cgit_parse_query(char *txt, configfn fn);
 extern struct commitinfo *cgit_parse_commit(struct commit *commit);
 
 extern void cache_prepare(struct cacheitem *item);
 extern int cache_lock(struct cacheitem *item);
 extern int cache_unlock(struct cacheitem *item);
 extern int cache_cancel_lock(struct cacheitem *item);
 extern int cache_exist(struct cacheitem *item);
 extern int cache_expired(struct cacheitem *item);
 
 extern char *cgit_repourl(const char *reponame);
 extern char *cgit_pageurl(const char *reponame, const char *pagename, 
                           const char *query);
 
 extern void cgit_print_error(char *msg);
 extern void cgit_print_date(unsigned long secs);
 extern void cgit_print_docstart(char *title, struct cacheitem *item);
 extern void cgit_print_docend();
 extern void cgit_print_pageheader(char *title);
 
 extern void cgit_print_repolist(struct cacheitem *item);
 extern void cgit_print_summary();
 extern void cgit_print_log(const char *tip, int ofs, int cnt);
 extern void cgit_print_view(const char *hex);
 extern void cgit_print_tree(const char *hex);
 extern void cgit_print_commit(const char *hex);
 
 #endif /* CGIT_H */
diff --git a/shared.c b/shared.c
index 5f2a5ce..7149597 100644
--- a/shared.c
+++ b/shared.c
@@ -1,85 +1,88 @@
 /* shared.c: global vars + some callback functions
  *
  * Copyright (C) 2006 Lars Hjemli
  *
  * Licensed under GNU General Public License v2
  *   (see COPYING for full license text)
  */
 
 #include "cgit.h"
 
 char *cgit_root         = "/usr/src/git";
 char *cgit_root_title   = "Git repository browser";
 char *cgit_css          = "/cgit.css";
 char *cgit_logo         = "/git-logo.png";
 char *cgit_logo_link    = "http://www.kernel.org/pub/software/scm/git/docs/";
 char *cgit_virtual_root = NULL;
 
 char *cgit_cache_root   = "/var/cache/cgit";
 
+int cgit_nocache               =  0;
 int cgit_max_lock_attempts     =  5;
 int cgit_cache_root_ttl        =  5;
 int cgit_cache_repo_ttl        =  5;
 int cgit_cache_dynamic_ttl     =  5;
 int cgit_cache_static_ttl      = -1;
 int cgit_cache_max_create_time =  5;
 
 char *cgit_repo_name    = NULL;
 char *cgit_repo_desc    = NULL;
 char *cgit_repo_owner   = NULL;
 
 int cgit_query_has_symref = 0;
 int cgit_query_has_sha1   = 0;
 
 char *cgit_querystring  = NULL;
 char *cgit_query_repo   = NULL;
 char *cgit_query_page   = NULL;
 char *cgit_query_head   = NULL;
 char *cgit_query_sha1   = NULL;
 int   cgit_query_ofs    = 0;
 
 int htmlfd = 0;
 
 void cgit_global_config_cb(const char *name, const char *value)
 {
         if (!strcmp(name, "root"))
                 cgit_root = xstrdup(value);
         else if (!strcmp(name, "root-title"))
                 cgit_root_title = xstrdup(value);
         else if (!strcmp(name, "css"))
                 cgit_css = xstrdup(value);
         else if (!strcmp(name, "logo"))
                 cgit_logo = xstrdup(value);
         else if (!strcmp(name, "logo-link"))
                 cgit_logo_link = xstrdup(value);
         else if (!strcmp(name, "virtual-root"))
                 cgit_virtual_root = xstrdup(value);
+        else if (!strcmp(name, "nocache"))
+                cgit_nocache = atoi(value);
 }
 
 void cgit_repo_config_cb(const char *name, const char *value)
 {
         if (!strcmp(name, "name"))
                 cgit_repo_name = xstrdup(value);
         else if (!strcmp(name, "desc"))
                 cgit_repo_desc = xstrdup(value);
         else if (!strcmp(name, "owner"))
                 cgit_repo_owner = xstrdup(value);
 }
 
 void cgit_querystring_cb(const char *name, const char *value)
 {
         if (!strcmp(name,"r")) {
                 cgit_query_repo = xstrdup(value);
         } else if (!strcmp(name, "p")) {
                 cgit_query_page = xstrdup(value);
         } else if (!strcmp(name, "h")) {
                 cgit_query_head = xstrdup(value);
                 cgit_query_has_symref = 1;
         } else if (!strcmp(name, "id")) {
                 cgit_query_sha1 = xstrdup(value);
                 cgit_query_has_sha1 = 1;
         } else if (!strcmp(name, "ofs")) {
                 cgit_query_ofs = atoi(value);
         }
 }