1 files changed, 68 insertions, 0 deletions

diff --git a/cache.c b/cache.c
index e590d7b..b701e13 100644
--- a/cache.c
+++ b/cache.c
@@ -143,201 +143,269 @@ static int lock_slot(struct cache_slot *slot)
  * just deleted.
  */
 static int unlock_slot(struct cache_slot *slot, int replace_old_slot)
 {
         int err;
 
         if (replace_old_slot)
                 err = rename(slot->lock_name, slot->cache_name);
         else
                 err = unlink(slot->lock_name);
         return err;
 }
 
 /* Generate the content for the current cache slot by redirecting
  * stdout to the lock-fd and invoking the callback function
  */
 static int fill_slot(struct cache_slot *slot)
 {
         int tmp;
 
         /* Preserve stdout */
         tmp = dup(STDOUT_FILENO);
         if (tmp == -1)
                 return errno;
 
         /* Redirect stdout to lockfile */
         if (dup2(slot->lock_fd, STDOUT_FILENO) == -1)
                 return errno;
 
         /* Generate cache content */
         slot->fn(slot->cbdata);
 
         /* Restore stdout */
         if (dup2(tmp, STDOUT_FILENO) == -1)
                 return errno;
 
         /* Close the temporary filedescriptor */
         close(tmp);
         return 0;
 }
 
 /* Crude implementation of 32-bit FNV-1 hash algorithm,
  * see http://www.isthe.com/chongo/tech/comp/fnv/ for details
  * about the magic numbers.
  */
 #define FNV_OFFSET 0x811c9dc5
 #define FNV_PRIME  0x01000193
 
 unsigned long hash_str(const char *str)
 {
         unsigned long h = FNV_OFFSET;
         unsigned char *s = (unsigned char *)str;
 
         if (!s)
                 return h;
 
         while(*s) {
                 h *= FNV_PRIME;
                 h ^= *s++;
         }
         return h;
 }
 
 static int process_slot(struct cache_slot *slot)
 {
         int err;
 
         err = open_slot(slot);
         if (!err && slot->match) {
                 if (is_expired(slot)) {
                         if (!lock_slot(slot)) {
                                 /* If the cachefile has been replaced between
                                  * `open_slot` and `lock_slot`, we'll just
                                  * serve the stale content from the original
                                  * cachefile. This way we avoid pruning the
                                  * newly generated slot. The same code-path
                                  * is chosen if fill_slot() fails for some
                                  * reason.
                                  *
                                  * TODO? check if the new slot contains the
                                  * same key as the old one, since we would
                                  * prefer to serve the newest content.
                                  * This will require us to open yet another
                                  * file-descriptor and read and compare the
                                  * key from the new file, so for now we're
                                  * lazy and just ignore the new file.
                                  */
                                 if (is_modified(slot) || fill_slot(slot)) {
                                         unlock_slot(slot, 0);
                                         close_lock(slot);
                                 } else {
                                         close_slot(slot);
                                         unlock_slot(slot, 1);
                                         slot->cache_fd = slot->lock_fd;
                                 }
                         }
                 }
                 print_slot(slot);
                 close_slot(slot);
                 return 0;
         }
 
         /* If the cache slot does not exist (or its key doesn't match the
          * current key), lets try to create a new cache slot for this
          * request. If this fails (for whatever reason), lets just generate
          * the content without caching it and fool the caller to belive
          * everything worked out (but print a warning on stdout).
          */
 
         close_slot(slot);
         if ((err = lock_slot(slot)) != 0) {
                 cache_log("[cgit] Unable to lock slot %s: %s (%d)\n",
                           slot->lock_name, strerror(err), err);
                 slot->fn(slot->cbdata);
                 return 0;
         }
 
         if ((err = fill_slot(slot)) != 0) {
                 cache_log("[cgit] Unable to fill slot %s: %s (%d)\n",
                           slot->lock_name, strerror(err), err);
                 unlock_slot(slot, 0);
                 close_lock(slot);
                 slot->fn(slot->cbdata);
                 return 0;
         }
         // We've got a valid cache slot in the lock file, which
         // is about to replace the old cache slot. But if we
         // release the lockfile and then try to open the new cache
         // slot, we might get a race condition with a concurrent
         // writer for the same cache slot (with a different key).
         // Lets avoid such a race by just printing the content of
         // the lock file.
         slot->cache_fd = slot->lock_fd;
         unlock_slot(slot, 1);
         err = print_slot(slot);
         close_slot(slot);
         return err;
 }
 
 /* Print cached content to stdout, generate the content if necessary. */
 int cache_process(int size, const char *path, const char *key, int ttl,
                   cache_fill_fn fn, void *cbdata)
 {
         unsigned long hash;
         int len, i;
         char filename[1024];
         char lockname[1024 + 5];  /* 5 = ".lock" */
         struct cache_slot slot;
 
         /* If the cache is disabled, just generate the content */
         if (size <= 0) {
                 fn(cbdata);
                 return 0;
         }
 
         /* Verify input, calculate filenames */
         if (!path) {
                 cache_log("[cgit] Cache path not specified, caching is disabled\n");
                 fn(cbdata);
                 return 0;
         }
         len = strlen(path);
         if (len > sizeof(filename) - 10) { /* 10 = "/01234567\0" */
                 cache_log("[cgit] Cache path too long, caching is disabled: %s\n",
                           path);
                 fn(cbdata);
                 return 0;
         }
         if (!key)
                 key = "";
         hash = hash_str(key) % size;
         strcpy(filename, path);
         if (filename[len - 1] != '/')
                 filename[len++] = '/';
         for(i = 0; i < 8; i++) {
                 sprintf(filename + len++, "%x",
                         (unsigned char)(hash & 0xf));
                 hash >>= 4;
         }
         filename[len] = '\0';
         strcpy(lockname, filename);
         strcpy(lockname + len, ".lock");
         slot.fn = fn;
         slot.cbdata = cbdata;
         slot.ttl = ttl;
         slot.cache_name = filename;
         slot.lock_name = lockname;
         slot.key = key;
         slot.keylen = strlen(key);
         return process_slot(&slot);
 }
 
+/* Return a strftime formatted date/time
+ * NB: the result from this function is to shared memory
+ */
+char *sprintftime(const char *format, time_t time)
+{
+        static char buf[64];
+        struct tm *tm;
+
+        if (!time)
+                return NULL;
+        tm = gmtime(&time);
+        strftime(buf, sizeof(buf)-1, format, tm);
+        return buf;
+}
+
+int cache_ls(const char *path)
+{
+        DIR *dir;
+        struct dirent *ent;
+        int err = 0;
+        struct cache_slot slot;
+        char fullname[1024];
+        char *name;
+
+        if (!path) {
+                cache_log("[cgit] cache path not specified\n");
+                return -1;
+        }
+        if (strlen(path) > 1024 - 10) {
+                cache_log("[cgit] cache path too long: %s\n",
+                          path);
+                return -1;
+        }
+        dir = opendir(path);
+        if (!dir) {
+                err = errno;
+                cache_log("[cgit] unable to open path %s: %s (%d)\n",
+                          path, strerror(err), err);
+                return err;
+        }
+        strcpy(fullname, path);
+        name = fullname + strlen(path);
+        if (*(name - 1) != '/') {
+                *name++ = '/';
+                *name = '\0';
+        }
+        slot.cache_name = fullname;
+        while((ent = readdir(dir)) != NULL) {
+                if (strlen(ent->d_name) != 8)
+                        continue;
+                strcpy(name, ent->d_name);
+                if ((err = open_slot(&slot)) != 0) {
+                        cache_log("[cgit] unable to open path %s: %s (%d)\n",
+                                  fullname, strerror(err), err);
+                        continue;
+                }
+                printf("%s %s %10lld %s\n",
+                       name,
+                       sprintftime("%Y-%m-%d %H:%M:%S",
+                                   slot.cache_st.st_mtime),
+                       slot.cache_st.st_size,
+                       slot.buf);
+                close_slot(&slot);
+        }
+        closedir(dir);
+        return 0;
+}
+
 /* Print a message to stdout */
 void cache_log(const char *format, ...)
 {
         va_list args;
         va_start(args, format);
         vfprintf(stderr, format, args);
         va_end(args);
 }