diff options
author | Kevin Wolf <kwolf@redhat.com> | 2010-09-13 18:06:11 +0200 |
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committer | Kevin Wolf <kwolf@redhat.com> | 2010-09-21 15:39:42 +0200 |
commit | b8a83a4f79ca4cd0689117b119ffaa1a91b00d52 (patch) | |
tree | 5ec0a1fba8c948f1129cfe5bf8ea3e0a0cc93990 | |
parent | 1b2adf28030ee3a570ba3a22401d44da2b18fe01 (diff) | |
download | hqemu-b8a83a4f79ca4cd0689117b119ffaa1a91b00d52.zip hqemu-b8a83a4f79ca4cd0689117b119ffaa1a91b00d52.tar.gz |
cutils: qemu_iovec_copy and qemu_iovec_memset
This adds two functions that work on QEMUIOVectors and will be used by the next
qcow2 patches.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
-rw-r--r-- | cutils.c | 50 | ||||
-rw-r--r-- | qemu-common.h | 3 |
2 files changed, 44 insertions, 9 deletions
@@ -168,30 +168,50 @@ void qemu_iovec_add(QEMUIOVector *qiov, void *base, size_t len) } /* - * Copies iovecs from src to the end dst until src is completely copied or the - * total size of the copied iovec reaches size. The size of the last copied - * iovec is changed in order to fit the specified total size if it isn't a - * perfect fit already. + * Copies iovecs from src to the end of dst. It starts copying after skipping + * the given number of bytes in src and copies until src is completely copied + * or the total size of the copied iovec reaches size.The size of the last + * copied iovec is changed in order to fit the specified total size if it isn't + * a perfect fit already. */ -void qemu_iovec_concat(QEMUIOVector *dst, QEMUIOVector *src, size_t size) +void qemu_iovec_copy(QEMUIOVector *dst, QEMUIOVector *src, uint64_t skip, + size_t size) { int i; size_t done; + void *iov_base; + uint64_t iov_len; assert(dst->nalloc != -1); done = 0; for (i = 0; (i < src->niov) && (done != size); i++) { - if (done + src->iov[i].iov_len > size) { - qemu_iovec_add(dst, src->iov[i].iov_base, size - done); + if (skip >= src->iov[i].iov_len) { + /* Skip the whole iov */ + skip -= src->iov[i].iov_len; + continue; + } else { + /* Skip only part (or nothing) of the iov */ + iov_base = (uint8_t*) src->iov[i].iov_base + skip; + iov_len = src->iov[i].iov_len - skip; + skip = 0; + } + + if (done + iov_len > size) { + qemu_iovec_add(dst, iov_base, size - done); break; } else { - qemu_iovec_add(dst, src->iov[i].iov_base, src->iov[i].iov_len); + qemu_iovec_add(dst, iov_base, iov_len); } - done += src->iov[i].iov_len; + done += iov_len; } } +void qemu_iovec_concat(QEMUIOVector *dst, QEMUIOVector *src, size_t size) +{ + qemu_iovec_copy(dst, src, 0, size); +} + void qemu_iovec_destroy(QEMUIOVector *qiov) { assert(qiov->nalloc != -1); @@ -234,6 +254,18 @@ void qemu_iovec_from_buffer(QEMUIOVector *qiov, const void *buf, size_t count) } } +void qemu_iovec_memset(QEMUIOVector *qiov, int c, size_t count) +{ + size_t n; + int i; + + for (i = 0; i < qiov->niov && count; ++i) { + n = MIN(count, qiov->iov[i].iov_len); + memset(qiov->iov[i].iov_base, c, n); + count -= n; + } +} + #ifndef _WIN32 /* Sets a specific flag */ int fcntl_setfl(int fd, int flag) diff --git a/qemu-common.h b/qemu-common.h index dfd3dc0..5544ffd 100644 --- a/qemu-common.h +++ b/qemu-common.h @@ -278,11 +278,14 @@ typedef struct QEMUIOVector { void qemu_iovec_init(QEMUIOVector *qiov, int alloc_hint); void qemu_iovec_init_external(QEMUIOVector *qiov, struct iovec *iov, int niov); void qemu_iovec_add(QEMUIOVector *qiov, void *base, size_t len); +void qemu_iovec_copy(QEMUIOVector *dst, QEMUIOVector *src, uint64_t skip, + size_t size); void qemu_iovec_concat(QEMUIOVector *dst, QEMUIOVector *src, size_t size); void qemu_iovec_destroy(QEMUIOVector *qiov); void qemu_iovec_reset(QEMUIOVector *qiov); void qemu_iovec_to_buffer(QEMUIOVector *qiov, void *buf); void qemu_iovec_from_buffer(QEMUIOVector *qiov, const void *buf, size_t count); +void qemu_iovec_memset(QEMUIOVector *qiov, int c, size_t count); struct Monitor; typedef struct Monitor Monitor; |