util/iov.c: Upgrade to 2.0.0
Change-Id: Id79be23e1af55e1a914f7d35a0ad4201691ae71d
diff --git a/include/qemu-common.h b/include/qemu-common.h
index 293c5ab..d8ba3d1 100644
--- a/include/qemu-common.h
+++ b/include/qemu-common.h
@@ -346,6 +346,8 @@
const void *buf, size_t bytes);
size_t qemu_iovec_memset(QEMUIOVector *qiov, size_t offset,
int fillc, size_t bytes);
+ssize_t qemu_iovec_compare(QEMUIOVector *a, QEMUIOVector *b);
+void qemu_iovec_clone(QEMUIOVector *dest, const QEMUIOVector *src, void *buf);
bool buffer_is_zero(const void *buf, size_t len);
@@ -444,22 +446,6 @@
#define CLAMP_MAC_TIMEOUT(to) ((void)0)
#endif // _DARWIN_C_SOURCE
-#if defined(__clang__) || defined(__llvm__)
-/* Clang and llvm-gcc don't support global register variable (GRV).
- Clang issues compile-time error for GRV. llvm-gcc accepts GRV (because
- its front-end is gcc) but ignores it in the llvm-based back-end.
- Undefining GRV decl to allow external/qemu and the rest of Android
- to compile. But emulator built w/o GRV support will not function
- correctly. User will be greeted with an error message (issued
- in tcg/tcg.c) when emulator built this way is launched.
- */
-#define SUPPORT_GLOBAL_REGISTER_VARIABLE 0
-#define GLOBAL_REGISTER_VARIABLE_DECL
-#else
-#define SUPPORT_GLOBAL_REGISTER_VARIABLE 1
-#define GLOBAL_REGISTER_VARIABLE_DECL register
-#endif /* __clang__ || __llvm__ */
-
/* vector definitions */
#ifdef __ALTIVEC__
#include <altivec.h>
diff --git a/util/iov.c b/util/iov.c
index bb46c04..03934da 100644
--- a/util/iov.c
+++ b/util/iov.c
@@ -378,6 +378,112 @@
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)
{
