Make evbuffer_add_file() work on windows

Right now only the add_file() mode is supported, when it would be
nicer to have mmap support.  Perhaps for Libevent 2.1.x.

diff --git a/buffer.c b/buffer.c
index 66a27c4b46ef402c8f5a8d2953171e0dc311cf99..5a48802346e21ef234db445978ae4dbfe4206cff 100644 (file)
--- a/buffer.c
+++ b/buffer.c
@@ -141,6 +141,13 @@ static int evbuffer_ptr_memcmp(const struct evbuffer *buf,
 static struct evbuffer_chain *evbuffer_expand_singlechain(struct evbuffer *buf,
     size_t datlen);
 
+#ifdef WIN32
+static int evbuffer_readfile(struct evbuffer *buf, evutil_socket_t fd,
+    int howmuch);
+#else
+#define evbuffer_readfile evbuffer_read
+#endif
+
 static struct evbuffer_chain *
 evbuffer_chain_new(size_t size)
 {
@@ -1998,6 +2005,56 @@ done:
        return result;
 }
 
+#ifdef WIN32
+static int
+evbuffer_readfile(struct evbuffer *buf, evutil_socket_t fd, int howmuch)
+{
+       int result;
+       int nchains, n;
+       struct evbuffer_iovec v[2];
+
+       EVBUFFER_LOCK(buf);
+
+       if (buf->freeze_end) {
+               result = -1;
+               goto done;
+       }
+
+       if (howmuch < 0)
+               howmuch = 16384;
+
+
+       /* XXX we _will_ waste some space here if there is any space left
+        * over on buf->last. */
+       nchains = evbuffer_reserve_space(buf, howmuch, v, 2);
+        if (nchains < 1 || nchains > 2) {
+               result = -1;
+               goto done;
+       }
+       n = read(fd, v[0].iov_base, v[0].iov_len);
+       if (n <= 0) {
+               result = n;
+               goto done;
+       }
+       v[0].iov_len = n;
+       if (nchains > 1) {
+               n = read(fd, v[1].iov_base, v[1].iov_len);
+               if (n <= 0) {
+                       result = v[0].iov_len;
+                       evbuffer_commit_space(buf, v, 1);
+                       goto done;
+               }
+               v[1].iov_len = n;
+       }
+       evbuffer_commit_space(buf, v, nchains);
+
+       result = n;
+done:
+       EVBUFFER_UNLOCK(buf);
+       return result;
+}
+#endif
+
 #ifdef USE_IOVEC_IMPL
 static inline int
 evbuffer_write_iovec(struct evbuffer *buffer, evutil_socket_t fd,
@@ -2592,7 +2649,7 @@ evbuffer_add_file(struct evbuffer *outbuf, int fd,
                 * can abort without side effects if the read fails.
                 */
                while (length) {
-                       read = evbuffer_read(tmp, fd, length);
+                       read = evbuffer_readfile(tmp, fd, length);
                        if (read == -1) {
                                evbuffer_free(tmp);
                                return (-1);

diff --git a/test/regress_buffer.c b/test/regress_buffer.c
index fa24738e653fcb0edd70751a8514f6f88604a974..057a0a212d548a302c28b9d5089648030c5252bd 100644 (file)
--- a/test/regress_buffer.c
+++ b/test/regress_buffer.c
@@ -596,6 +596,8 @@ test_evbuffer_add_file(void *ptr)
        const char *compare;
        evutil_socket_t fd, pair[2];
 
+       /* Add a test for a big file. XXXX */
+
        tt_assert(impl);
        if (!strcmp(impl, "sendfile")) {
                if (!_evbuffer_testing_use_sendfile())