target-i386: fix "info lapic" segfault on isapc

[mirror_qemu.git] / util / iov.c

diff --git a/util/iov.c b/util/iov.c
index 03934da74dc280d3692c21e0db607fbf4ddbe6b7..74e6ca8ed7298c833e52257923c10fb73c9377ad 100644 (file)
--- a/util/iov.c
+++ b/util/iov.c
@@ -16,18 +16,14 @@
  * GNU GPL, version 2 or (at your option) any later version.
  */
 
+#include "qemu/osdep.h"
+#include "qemu-common.h"
 #include "qemu/iov.h"
+#include "qemu/sockets.h"
+#include "qemu/cutils.h"
 
-#ifdef _WIN32
-# include <windows.h>
-# include <winsock2.h>
-#else
-# include <sys/types.h>
-# include <sys/socket.h>
-#endif
-
-size_t iov_from_buf(const struct iovec *iov, unsigned int iov_cnt,
-                    size_t offset, const void *buf, size_t bytes)
+size_t iov_from_buf_full(const struct iovec *iov, unsigned int iov_cnt,
+                         size_t offset, const void *buf, size_t bytes)
 {
     size_t done;
     unsigned int i;
@@ -45,8 +41,8 @@ size_t iov_from_buf(const struct iovec *iov, unsigned int iov_cnt,
     return done;
 }
 
-size_t iov_to_buf(const struct iovec *iov, const unsigned int iov_cnt,
-                  size_t offset, void *buf, size_t bytes)
+size_t iov_to_buf_full(const struct iovec *iov, const unsigned int iov_cnt,
+                       size_t offset, void *buf, size_t bytes)
 {
     size_t done;
     unsigned int i;
@@ -140,7 +136,7 @@ do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send)
 #endif
 }
 
-ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
+ssize_t iov_send_recv(int sockfd, const struct iovec *_iov, unsigned iov_cnt,
                       size_t offset, size_t bytes,
                       bool do_send)
 {
@@ -148,6 +144,16 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
     ssize_t ret;
     size_t orig_len, tail;
     unsigned niov;
+    struct iovec *local_iov, *iov;
+
+    if (bytes <= 0) {
+        return 0;
+    }
+
+    local_iov = g_new0(struct iovec, iov_cnt);
+    iov_copy(local_iov, iov_cnt, _iov, iov_cnt, offset, bytes);
+    offset = 0;
+    iov = local_iov;
 
     while (bytes > 0) {
         /* Find the start position, skipping `offset' bytes:
@@ -194,6 +200,7 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
 
         if (ret < 0) {
             assert(errno != EINTR);
+            g_free(local_iov);
             if (errno == EAGAIN && total > 0) {
                 return total;
             }
@@ -212,6 +219,7 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
         bytes -= ret;
     }
 
+    g_free(local_iov);
     return total;
 }
 
@@ -239,7 +247,8 @@ unsigned iov_copy(struct iovec *dst_iov, unsigned int dst_iov_cnt,
 {
     size_t len;
     unsigned int i, j;
-    for (i = 0, j = 0; i < iov_cnt && j < dst_iov_cnt && bytes; i++) {
+    for (i = 0, j = 0;
+         i < iov_cnt && j < dst_iov_cnt && (offset || bytes); i++) {
         if (offset >= iov[i].iov_len) {
             offset -= iov[i].iov_len;
             continue;
@@ -260,7 +269,7 @@ unsigned iov_copy(struct iovec *dst_iov, unsigned int dst_iov_cnt,
 
 void qemu_iovec_init(QEMUIOVector *qiov, int alloc_hint)
 {
-    qiov->iov = g_malloc(alloc_hint * sizeof(struct iovec));
+    qiov->iov = g_new(struct iovec, alloc_hint);
     qiov->niov = 0;
     qiov->nalloc = alloc_hint;
     qiov->size = 0;
@@ -284,7 +293,7 @@ void qemu_iovec_add(QEMUIOVector *qiov, void *base, size_t len)
 
     if (qiov->niov == qiov->nalloc) {
         qiov->nalloc = 2 * qiov->nalloc + 1;
-        qiov->iov = g_realloc(qiov->iov, qiov->nalloc * sizeof(struct iovec));
+        qiov->iov = g_renew(struct iovec, qiov->iov, qiov->nalloc);
     }
     qiov->iov[qiov->niov].iov_base = base;
     qiov->iov[qiov->niov].iov_len = len;
@@ -302,15 +311,15 @@ void qemu_iovec_add(QEMUIOVector *qiov, void *base, size_t len)
  * of src".
  * Only vector pointers are processed, not the actual data buffers.
  */
-void qemu_iovec_concat_iov(QEMUIOVector *dst,
-                           struct iovec *src_iov, unsigned int src_cnt,
-                           size_t soffset, size_t sbytes)
+size_t qemu_iovec_concat_iov(QEMUIOVector *dst,
+                             struct iovec *src_iov, unsigned int src_cnt,
+                             size_t soffset, size_t sbytes)
 {
     int i;
     size_t done;
 
     if (!sbytes) {
-        return;
+        return 0;
     }
     assert(dst->nalloc != -1);
     for (i = 0, done = 0; done < sbytes && i < src_cnt; i++) {
@@ -324,6 +333,8 @@ void qemu_iovec_concat_iov(QEMUIOVector *dst,
         }
     }
     assert(soffset == 0); /* offset beyond end of src */
+
+    return done;
 }
 
 /*
@@ -342,6 +353,27 @@ void qemu_iovec_concat(QEMUIOVector *dst,
     qemu_iovec_concat_iov(dst, src->iov, src->niov, soffset, sbytes);
 }
 
+/*
+ * Check if the contents of the iovecs are all zero
+ */
+bool qemu_iovec_is_zero(QEMUIOVector *qiov)
+{
+    int i;
+    for (i = 0; i < qiov->niov; i++) {
+        size_t offs = QEMU_ALIGN_DOWN(qiov->iov[i].iov_len, 4 * sizeof(long));
+        uint8_t *ptr = qiov->iov[i].iov_base;
+        if (offs && !buffer_is_zero(qiov->iov[i].iov_base, offs)) {
+            return false;
+        }
+        for (; offs < qiov->iov[i].iov_len; offs++) {
+            if (ptr[offs]) {
+                return false;
+            }
+        }
+    }
+    return true;
+}
+
 void qemu_iovec_destroy(QEMUIOVector *qiov)
 {
     assert(qiov->nalloc != -1);
@@ -534,3 +566,16 @@ size_t iov_discard_back(struct iovec *iov, unsigned int *iov_cnt,
 
     return total;
 }
+
+void qemu_iovec_discard_back(QEMUIOVector *qiov, size_t bytes)
+{
+    size_t total;
+    unsigned int niov = qiov->niov;
+
+    assert(qiov->size >= bytes);
+    total = iov_discard_back(qiov->iov, &niov, bytes);
+    assert(total == bytes);
+
+    qiov->niov = niov;
+    qiov->size -= bytes;
+}