Update COPYING

[cgit.git] / cache.c

diff --git a/cache.c b/cache.c
index fcd461ffe20e29d111e8186f6e924c096f2099e6..2c70be784d6187cb63d20475e8c6df203b6bb31f 100644 (file)
--- a/cache.c
+++ b/cache.c
@@ -16,21 +16,24 @@
 #include "cgit.h"
 #include "cache.h"
 #include "html.h"
+#ifdef HAVE_LINUX_SENDFILE
+#include <sys/sendfile.h>
+#endif
 
 #define CACHE_BUFSIZE (1024 * 4)
 
 struct cache_slot {
        const char *key;
-       int keylen;
+       size_t keylen;
        int ttl;
        cache_fill_fn fn;
        int cache_fd;
        int lock_fd;
+       int stdout_fd;
        const char *cache_name;
        const char *lock_name;
        int match;
        struct stat cache_st;
-       struct stat lock_st;
        int bufsize;
        char buf[CACHE_BUFSIZE];
 };
@@ -42,7 +45,7 @@ struct cache_slot {
 static int open_slot(struct cache_slot *slot)
 {
        char *bufz;
-       int bufkeylen = -1;
+       ssize_t bufkeylen = -1;
 
        slot->cache_fd = open(slot->cache_name, O_RDONLY);
        if (slot->cache_fd == -1)
@@ -59,8 +62,9 @@ static int open_slot(struct cache_slot *slot)
        if (bufz)
                bufkeylen = bufz - slot->buf;
 
-       slot->match = bufkeylen == slot->keylen &&
-           !memcmp(slot->key, slot->buf, bufkeylen + 1);
+       if (slot->key)
+               slot->match = bufkeylen == slot->keylen &&
+                   !memcmp(slot->key, slot->buf, bufkeylen + 1);
 
        return 0;
 }
@@ -81,6 +85,23 @@ static int close_slot(struct cache_slot *slot)
 /* Print the content of the active cache slot (but skip the key). */
 static int print_slot(struct cache_slot *slot)
 {
+#ifdef HAVE_LINUX_SENDFILE
+       off_t start_off;
+       int ret;
+
+       start_off = slot->keylen + 1;
+
+       do {
+               ret = sendfile(STDOUT_FILENO, slot->cache_fd, &start_off,
+                               slot->cache_st.st_size - start_off);
+               if (ret < 0) {
+                       if (errno == EAGAIN || errno == EINTR)
+                               continue;
+                       return errno;
+               }
+               return 0;
+       } while (1);
+#else
        ssize_t i, j;
 
        i = lseek(slot->cache_fd, slot->keylen + 1, SEEK_SET);
@@ -97,6 +118,7 @@ static int print_slot(struct cache_slot *slot)
                return errno;
        else
                return 0;
+#endif
 }
 
 /* Check if the slot has expired */
@@ -141,10 +163,23 @@ static int close_lock(struct cache_slot *slot)
  */
 static int lock_slot(struct cache_slot *slot)
 {
-       slot->lock_fd = open(slot->lock_name, O_RDWR | O_CREAT | O_EXCL,
+       struct flock lock = {
+               .l_type = F_WRLCK,
+               .l_whence = SEEK_SET,
+               .l_start = 0,
+               .l_len = 0,
+       };
+
+       slot->lock_fd = open(slot->lock_name, O_RDWR | O_CREAT,
                             S_IRUSR | S_IWUSR);
        if (slot->lock_fd == -1)
                return errno;
+       if (fcntl(slot->lock_fd, F_SETLK, &lock) < 0) {
+               int saved_errno = errno;
+               close(slot->lock_fd);
+               slot->lock_fd = -1;
+               return saved_errno;
+       }
        if (xwrite(slot->lock_fd, slot->key, slot->keylen + 1) < 0)
                return errno;
        return 0;
@@ -163,6 +198,13 @@ static int unlock_slot(struct cache_slot *slot, int replace_old_slot)
        else
                err = unlink(slot->lock_name);
 
+       /* Restore stdout and close the temporary FD. */
+       if (slot->stdout_fd >= 0) {
+               dup2(slot->stdout_fd, STDOUT_FILENO);
+               close(slot->stdout_fd);
+               slot->stdout_fd = -1;
+       }
+
        if (err)
                return errno;
 
@@ -174,11 +216,9 @@ static int unlock_slot(struct cache_slot *slot, int replace_old_slot)
  */
 static int fill_slot(struct cache_slot *slot)
 {
-       int tmp;
-
        /* Preserve stdout */
-       tmp = dup(STDOUT_FILENO);
-       if (tmp == -1)
+       slot->stdout_fd = dup(STDOUT_FILENO);
+       if (slot->stdout_fd == -1)
                return errno;
 
        /* Redirect stdout to lockfile */
@@ -188,12 +228,12 @@ static int fill_slot(struct cache_slot *slot)
        /* Generate cache content */
        slot->fn();
 
-       /* Restore stdout */
-       if (dup2(tmp, STDOUT_FILENO) == -1)
+       /* Make sure any buffered data is flushed to the file */
+       if (fflush(stdout))
                return errno;
 
-       /* Close the temporary filedescriptor */
-       if (close(tmp))
+       /* update stat info */
+       if (fstat(slot->lock_fd, &slot->cache_st))
                return errno;
 
        return 0;
@@ -268,7 +308,7 @@ static int process_slot(struct cache_slot *slot)
        /* 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
+        * the content without caching it and fool the caller to believe
         * everything worked out (but print a warning on stdout).
         */
 
@@ -319,7 +359,7 @@ int cache_process(int size, const char *path, const char *key, int ttl,
        int result;
 
        /* If the cache is disabled, just generate the content */
-       if (size <= 0) {
+       if (size <= 0 || ttl == 0) {
                fn();
                return 0;
        }
@@ -343,6 +383,7 @@ int cache_process(int size, const char *path, const char *key, int ttl,
        strbuf_addstr(&lockname, ".lock");
        slot.fn = fn;
        slot.ttl = ttl;
+       slot.stdout_fd = -1;
        slot.cache_name = filename.buf;
        slot.lock_name = lockname.buf;
        slot.key = key;
@@ -374,7 +415,7 @@ int cache_ls(const char *path)
        DIR *dir;
        struct dirent *ent;
        int err = 0;
-       struct cache_slot slot = { 0 };
+       struct cache_slot slot = { NULL };
        struct strbuf fullname = STRBUF_INIT;
        size_t prefixlen;