summaryrefslogtreecommitdiffstats
path: root/iov.c
diff options
context:
space:
mode:
Diffstat (limited to 'iov.c')
-rw-r--r--iov.c103
1 files changed, 103 insertions, 0 deletions
diff --git a/iov.c b/iov.c
index b7378bf..a81eedc 100644
--- a/iov.c
+++ b/iov.c
@@ -251,3 +251,106 @@ unsigned iov_copy(struct iovec *dst_iov, unsigned int dst_iov_cnt,
assert(offset == 0);
return j;
}
+
+/* io vectors */
+
+void qemu_iovec_init(QEMUIOVector *qiov, int alloc_hint)
+{
+ qiov->iov = g_malloc(alloc_hint * sizeof(struct iovec));
+ qiov->niov = 0;
+ qiov->nalloc = alloc_hint;
+ qiov->size = 0;
+}
+
+void qemu_iovec_init_external(QEMUIOVector *qiov, struct iovec *iov, int niov)
+{
+ int i;
+
+ qiov->iov = iov;
+ qiov->niov = niov;
+ qiov->nalloc = -1;
+ qiov->size = 0;
+ for (i = 0; i < niov; i++)
+ qiov->size += iov[i].iov_len;
+}
+
+void qemu_iovec_add(QEMUIOVector *qiov, void *base, size_t len)
+{
+ assert(qiov->nalloc != -1);
+
+ if (qiov->niov == qiov->nalloc) {
+ qiov->nalloc = 2 * qiov->nalloc + 1;
+ qiov->iov = g_realloc(qiov->iov, qiov->nalloc * sizeof(struct iovec));
+ }
+ qiov->iov[qiov->niov].iov_base = base;
+ qiov->iov[qiov->niov].iov_len = len;
+ qiov->size += len;
+ ++qiov->niov;
+}
+
+/*
+ * Concatenates (partial) iovecs from src to the end of dst.
+ * It starts copying after skipping `soffset' bytes at the
+ * beginning of src and adds individual vectors from src to
+ * dst copies up to `sbytes' bytes total, or up to the end
+ * of src if it comes first. This way, it is okay to specify
+ * very large value for `sbytes' to indicate "up to the end
+ * of src".
+ * Only vector pointers are processed, not the actual data buffers.
+ */
+void qemu_iovec_concat(QEMUIOVector *dst,
+ QEMUIOVector *src, size_t soffset, size_t sbytes)
+{
+ int i;
+ size_t done;
+ struct iovec *siov = src->iov;
+ assert(dst->nalloc != -1);
+ assert(src->size >= soffset);
+ for (i = 0, done = 0; done < sbytes && i < src->niov; i++) {
+ if (soffset < siov[i].iov_len) {
+ size_t len = MIN(siov[i].iov_len - soffset, sbytes - done);
+ qemu_iovec_add(dst, siov[i].iov_base + soffset, len);
+ done += len;
+ soffset = 0;
+ } else {
+ soffset -= siov[i].iov_len;
+ }
+ }
+ /* return done; */
+}
+
+void qemu_iovec_destroy(QEMUIOVector *qiov)
+{
+ assert(qiov->nalloc != -1);
+
+ qemu_iovec_reset(qiov);
+ g_free(qiov->iov);
+ qiov->nalloc = 0;
+ qiov->iov = NULL;
+}
+
+void qemu_iovec_reset(QEMUIOVector *qiov)
+{
+ assert(qiov->nalloc != -1);
+
+ qiov->niov = 0;
+ qiov->size = 0;
+}
+
+size_t qemu_iovec_to_buf(QEMUIOVector *qiov, size_t offset,
+ void *buf, size_t bytes)
+{
+ return iov_to_buf(qiov->iov, qiov->niov, offset, buf, bytes);
+}
+
+size_t qemu_iovec_from_buf(QEMUIOVector *qiov, size_t offset,
+ const void *buf, size_t bytes)
+{
+ return iov_from_buf(qiov->iov, qiov->niov, offset, buf, bytes);
+}
+
+size_t qemu_iovec_memset(QEMUIOVector *qiov, size_t offset,
+ int fillc, size_t bytes)
+{
+ return iov_memset(qiov->iov, qiov->niov, offset, fillc, bytes);
+}
OpenPOWER on IntegriCloud