* 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;
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;
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));
#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)
{
+ ssize_t total = 0;
ssize_t ret;
- unsigned si, ei; /* start and end indexes */
- 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.
- */
+ size_t orig_len, tail;
+ unsigned niov;
+ struct iovec *local_iov, *iov;
+
+ if (bytes <= 0) {
return 0;
}
- /* 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;
- }
- if (offset) {
- assert(si < iov_cnt);
- /* second, skip `offset' bytes from the (now) first element,
- * undo it on exit */
- iov[si].iov_base += offset;
- iov[si].iov_len -= offset;
- }
- /* Find the end position skipping `bytes' bytes: */
- /* first, skip all full-sized elements */
- for (ei = si; ei < iov_cnt && iov[ei].iov_len <= bytes; ++ei) {
- bytes -= iov[ei].iov_len;
- }
- if (bytes) {
- /* second, fixup the last element, and remember
- * the length we've cut from the end of it in `bytes' */
- size_t tail;
- assert(ei < iov_cnt);
- assert(iov[ei].iov_len > bytes);
- tail = iov[ei].iov_len - bytes;
- iov[ei].iov_len = bytes;
- bytes = tail; /* bytes is now equal to the tail size */
- ++ei;
- }
+ local_iov = g_new0(struct iovec, iov_cnt);
+ iov_copy(local_iov, iov_cnt, _iov, iov_cnt, offset, bytes);
+ offset = 0;
+ iov = local_iov;
- ret = do_send_recv(sockfd, iov + si, ei - si, do_send);
+ 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;
+ }
- /* Undo the changes above */
- if (offset) {
- iov[si].iov_base -= offset;
- iov[si].iov_len += offset;
- }
- if (bytes) {
- iov[ei-1].iov_len += bytes;
+ /* 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;
+ }
+
+ if (ret < 0) {
+ assert(errno != EINTR);
+ g_free(local_iov);
+ if (errno == EAGAIN && total > 0) {
+ return total;
+ }
+ return -1;
+ }
+
+ if (ret == 0 && !do_send) {
+ /* recv returns 0 when the peer has performed an orderly
+ * shutdown. */
+ break;
+ }
+
+ /* Prepare for the next iteration */
+ offset += ret;
+ total += ret;
+ bytes -= ret;
}
- return ret;
+ g_free(local_iov);
+ return total;
}
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);
}
{
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;
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;
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;
* 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++) {
}
}
assert(soffset == 0); /* offset beyond end of src */
+
+ return done;
}
/*
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);
return iov_memset(qiov->iov, qiov->niov, offset, fillc, bytes);
}
+/**
+ * Check that I/O vector contents are identical
+ *
+ * The IO vectors must have the same structure (same length of all parts).
+ * A typical usage is to compare vectors created with qemu_iovec_clone().
+ *
+ * @a: I/O vector
+ * @b: I/O vector
+ * @ret: Offset to first mismatching byte or -1 if match
+ */
+ssize_t qemu_iovec_compare(QEMUIOVector *a, QEMUIOVector *b)
+{
+ int i;
+ ssize_t offset = 0;
+
+ assert(a->niov == b->niov);
+ for (i = 0; i < a->niov; i++) {
+ size_t len = 0;
+ uint8_t *p = (uint8_t *)a->iov[i].iov_base;
+ uint8_t *q = (uint8_t *)b->iov[i].iov_base;
+
+ assert(a->iov[i].iov_len == b->iov[i].iov_len);
+ while (len < a->iov[i].iov_len && *p++ == *q++) {
+ len++;
+ }
+
+ offset += len;
+
+ if (len != a->iov[i].iov_len) {
+ return offset;
+ }
+ }
+ return -1;
+}
+
+typedef struct {
+ int src_index;
+ struct iovec *src_iov;
+ void *dest_base;
+} IOVectorSortElem;
+
+static int sortelem_cmp_src_base(const void *a, const void *b)
+{
+ const IOVectorSortElem *elem_a = a;
+ const IOVectorSortElem *elem_b = b;
+
+ /* Don't overflow */
+ if (elem_a->src_iov->iov_base < elem_b->src_iov->iov_base) {
+ return -1;
+ } else if (elem_a->src_iov->iov_base > elem_b->src_iov->iov_base) {
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+static int sortelem_cmp_src_index(const void *a, const void *b)
+{
+ const IOVectorSortElem *elem_a = a;
+ const IOVectorSortElem *elem_b = b;
+
+ return elem_a->src_index - elem_b->src_index;
+}
+
+/**
+ * Copy contents of I/O vector
+ *
+ * The relative relationships of overlapping iovecs are preserved. This is
+ * necessary to ensure identical semantics in the cloned I/O vector.
+ */
+void qemu_iovec_clone(QEMUIOVector *dest, const QEMUIOVector *src, void *buf)
+{
+ IOVectorSortElem sortelems[src->niov];
+ void *last_end;
+ int i;
+
+ /* Sort by source iovecs by base address */
+ for (i = 0; i < src->niov; i++) {
+ sortelems[i].src_index = i;
+ sortelems[i].src_iov = &src->iov[i];
+ }
+ qsort(sortelems, src->niov, sizeof(sortelems[0]), sortelem_cmp_src_base);
+
+ /* Allocate buffer space taking into account overlapping iovecs */
+ last_end = NULL;
+ for (i = 0; i < src->niov; i++) {
+ struct iovec *cur = sortelems[i].src_iov;
+ ptrdiff_t rewind = 0;
+
+ /* Detect overlap */
+ if (last_end && last_end > cur->iov_base) {
+ rewind = last_end - cur->iov_base;
+ }
+
+ sortelems[i].dest_base = buf - rewind;
+ buf += cur->iov_len - MIN(rewind, cur->iov_len);
+ last_end = MAX(cur->iov_base + cur->iov_len, last_end);
+ }
+
+ /* Sort by source iovec index and build destination iovec */
+ qsort(sortelems, src->niov, sizeof(sortelems[0]), sortelem_cmp_src_index);
+ for (i = 0; i < src->niov; i++) {
+ qemu_iovec_add(dest, sortelems[i].dest_base, src->iov[i].iov_len);
+ }
+}
+
size_t iov_discard_front(struct iovec **iov, unsigned int *iov_cnt,
size_t bytes)
{
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;
+}
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