hw/i386/Makefile.obj: use $(PYTHON) to run .py scripts consistently

[qemu.git] / util / iov.c

diff --git a/util/iov.c b/util/iov.c
index 110d18eba6ca3814e01577ec9050ee84f83973a9..bb46c04e4de323eb38fe3e9ff245a5978fe9f30f 100644 (file)
--- a/util/iov.c
+++ b/util/iov.c
@@ -99,7 +99,7 @@ size_t iov_size(const struct iovec *iov, const unsigned int iov_cnt)
 static ssize_t
 do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send)
 {
-#if defined CONFIG_IOVEC && defined CONFIG_POSIX
+#ifdef CONFIG_POSIX
     ssize_t ret;
     struct msghdr msg;
     memset(&msg, 0, sizeof(msg));
@@ -144,63 +144,75 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
                       size_t offset, size_t bytes,
                       bool do_send)
 {
+    ssize_t total = 0;
     ssize_t ret;
     size_t orig_len, tail;
-    unsigned si, ei;            /* start and end indexes */
+    unsigned niov;
 
-    if (bytes == 0) {
-        /* Catch the do-nothing case early, as otherwise we will pass an
-         * empty iovec to sendmsg/recvmsg(), and not all implementations
-         * accept this.
-         */
-        return 0;
-    }
+    while (bytes > 0) {
+        /* Find the start position, skipping `offset' bytes:
+         * first, skip all full-sized vector elements, */
+        for (niov = 0; niov < iov_cnt && offset >= iov[niov].iov_len; ++niov) {
+            offset -= iov[niov].iov_len;
+        }
 
-    /* Find the start position, skipping `offset' bytes:
-     * first, skip all full-sized vector elements, */
-    for (si = 0; si < iov_cnt && offset >= iov[si].iov_len; ++si) {
-        offset -= iov[si].iov_len;
-    }
+        /* niov == iov_cnt would only be valid if bytes == 0, which
+         * we already ruled out in the loop condition.  */
+        assert(niov < iov_cnt);
+        iov += niov;
+        iov_cnt -= niov;
+
+        if (offset) {
+            /* second, skip `offset' bytes from the (now) first element,
+             * undo it on exit */
+            iov[0].iov_base += offset;
+            iov[0].iov_len -= offset;
+        }
+        /* Find the end position skipping `bytes' bytes: */
+        /* first, skip all full-sized elements */
+        tail = bytes;
+        for (niov = 0; niov < iov_cnt && iov[niov].iov_len <= tail; ++niov) {
+            tail -= iov[niov].iov_len;
+        }
+        if (tail) {
+            /* second, fixup the last element, and remember the original
+             * length */
+            assert(niov < iov_cnt);
+            assert(iov[niov].iov_len > tail);
+            orig_len = iov[niov].iov_len;
+            iov[niov++].iov_len = tail;
+            ret = do_send_recv(sockfd, iov, niov, do_send);
+            /* Undo the changes above before checking for errors */
+            iov[niov-1].iov_len = orig_len;
+        } else {
+            ret = do_send_recv(sockfd, iov, niov, do_send);
+        }
+        if (offset) {
+            iov[0].iov_base -= offset;
+            iov[0].iov_len += offset;
+        }
 
-    /* si == iov_cnt would only be valid if bytes == 0, which
-     * we already ruled out above.  */
-    assert(si < iov_cnt);
-    iov += si;
-    iov_cnt -= si;
-
-    if (offset) {
-        /* second, skip `offset' bytes from the (now) first element,
-         * undo it on exit */
-        iov[0].iov_base += offset;
-        iov[0].iov_len -= offset;
-    }
-    /* Find the end position skipping `bytes' bytes: */
-    /* first, skip all full-sized elements */
-    tail = bytes;
-    for (ei = 0; ei < iov_cnt && iov[ei].iov_len <= tail; ++ei) {
-        tail -= iov[ei].iov_len;
-    }
-    if (tail) {
-        /* second, fixup the last element, and remember the original
-         * length */
-        assert(ei < iov_cnt);
-        assert(iov[ei].iov_len > tail);
-        orig_len = iov[ei].iov_len;
-        iov[ei++].iov_len = tail;
-    }
+        if (ret < 0) {
+            assert(errno != EINTR);
+            if (errno == EAGAIN && total > 0) {
+                return total;
+            }
+            return -1;
+        }
 
-    ret = do_send_recv(sockfd, iov, ei, do_send);
+        if (ret == 0 && !do_send) {
+            /* recv returns 0 when the peer has performed an orderly
+             * shutdown. */
+            break;
+        }
 
-    /* Undo the changes above */
-    if (tail) {
-        iov[ei-1].iov_len = orig_len;
-    }
-    if (offset) {
-        iov[0].iov_base -= offset;
-        iov[0].iov_len += offset;
+        /* Prepare for the next iteration */
+        offset += ret;
+        total += ret;
+        bytes -= ret;
     }
 
-    return ret;
+    return total;
 }
 
 
@@ -217,7 +229,7 @@ void iov_hexdump(const struct iovec *iov, const unsigned int iov_cnt,
     size = size > limit ? limit : size;
     buf = g_malloc(size);
     iov_to_buf(iov, iov_cnt, 0, buf, size);
-    hexdump(buf, fp, prefix, size);
+    qemu_hexdump(buf, fp, prefix, size);
     g_free(buf);
 }