Merge remote-tracking branch 'origin/master' into threadpool

[sdk/emulator/qemu.git] / iov.c

diff --git a/iov.c b/iov.c
index b7378bf..a81eedc 100644 (file)
--- 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);
+}