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Diffstat (limited to 'contrib/qemu/util/iov.c')
| -rw-r--r-- | contrib/qemu/util/iov.c | 426 |
1 files changed, 0 insertions, 426 deletions
diff --git a/contrib/qemu/util/iov.c b/contrib/qemu/util/iov.c deleted file mode 100644 index cc6e837c836..00000000000 --- a/contrib/qemu/util/iov.c +++ /dev/null @@ -1,426 +0,0 @@ -/* - * Helpers for getting linearized buffers from iov / filling buffers into iovs - * - * Copyright IBM, Corp. 2007, 2008 - * Copyright (C) 2010 Red Hat, Inc. - * - * Author(s): - * Anthony Liguori <aliguori@us.ibm.com> - * Amit Shah <amit.shah@redhat.com> - * Michael Tokarev <mjt@tls.msk.ru> - * - * This work is licensed under the terms of the GNU GPL, version 2. See - * the COPYING file in the top-level directory. - * - * Contributions after 2012-01-13 are licensed under the terms of the - * GNU GPL, version 2 or (at your option) any later version. - */ - -#include "qemu/iov.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 done; - unsigned int i; - for (i = 0, done = 0; (offset || done < bytes) && i < iov_cnt; i++) { - if (offset < iov[i].iov_len) { - size_t len = MIN(iov[i].iov_len - offset, bytes - done); - memcpy(iov[i].iov_base + offset, buf + done, len); - done += len; - offset = 0; - } else { - offset -= iov[i].iov_len; - } - } - assert(offset == 0); - 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 done; - unsigned int i; - for (i = 0, done = 0; (offset || done < bytes) && i < iov_cnt; i++) { - if (offset < iov[i].iov_len) { - size_t len = MIN(iov[i].iov_len - offset, bytes - done); - memcpy(buf + done, iov[i].iov_base + offset, len); - done += len; - offset = 0; - } else { - offset -= iov[i].iov_len; - } - } - assert(offset == 0); - return done; -} - -size_t iov_memset(const struct iovec *iov, const unsigned int iov_cnt, - size_t offset, int fillc, size_t bytes) -{ - size_t done; - unsigned int i; - for (i = 0, done = 0; (offset || done < bytes) && i < iov_cnt; i++) { - if (offset < iov[i].iov_len) { - size_t len = MIN(iov[i].iov_len - offset, bytes - done); - memset(iov[i].iov_base + offset, fillc, len); - done += len; - offset = 0; - } else { - offset -= iov[i].iov_len; - } - } - assert(offset == 0); - return done; -} - -size_t iov_size(const struct iovec *iov, const unsigned int iov_cnt) -{ - size_t len; - unsigned int i; - - len = 0; - for (i = 0; i < iov_cnt; i++) { - len += iov[i].iov_len; - } - return len; -} - -/* helper function for iov_send_recv() */ -static ssize_t -do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send) -{ -#ifdef CONFIG_POSIX - ssize_t ret; - struct msghdr msg; - memset(&msg, 0, sizeof(msg)); - msg.msg_iov = iov; - msg.msg_iovlen = iov_cnt; - do { - ret = do_send - ? sendmsg(sockfd, &msg, 0) - : recvmsg(sockfd, &msg, 0); - } while (ret < 0 && errno == EINTR); - return ret; -#else - /* else send piece-by-piece */ - /*XXX Note: windows has WSASend() and WSARecv() */ - unsigned i = 0; - ssize_t ret = 0; - while (i < iov_cnt) { - ssize_t r = do_send - ? send(sockfd, iov[i].iov_base, iov[i].iov_len, 0) - : recv(sockfd, iov[i].iov_base, iov[i].iov_len, 0); - if (r > 0) { - ret += r; - } else if (!r) { - break; - } else if (errno == EINTR) { - continue; - } else { - /* else it is some "other" error, - * only return if there was no data processed. */ - if (ret == 0) { - ret = -1; - } - break; - } - i++; - } - return ret; -#endif -} - -ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, - size_t offset, size_t bytes, - bool do_send) -{ - ssize_t total = 0; - ssize_t ret; - size_t orig_len, tail; - unsigned niov; - - 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; - } - - /* 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 */ - if (tail) { - iov[niov-1].iov_len = orig_len; - } - if (offset) { - iov[0].iov_base -= offset; - iov[0].iov_len += offset; - } - - if (ret < 0) { - assert(errno != EINTR); - if (errno == EAGAIN && total > 0) { - return total; - } - return -1; - } - - /* Prepare for the next iteration */ - offset += ret; - total += ret; - bytes -= ret; - } - - return total; -} - - -void iov_hexdump(const struct iovec *iov, const unsigned int iov_cnt, - FILE *fp, const char *prefix, size_t limit) -{ - int v; - size_t size = 0; - char *buf; - - for (v = 0; v < iov_cnt; v++) { - size += iov[v].iov_len; - } - size = size > limit ? limit : size; - buf = g_malloc(size); - iov_to_buf(iov, iov_cnt, 0, buf, size); - qemu_hexdump(buf, fp, prefix, size); - g_free(buf); -} - -unsigned iov_copy(struct iovec *dst_iov, unsigned int dst_iov_cnt, - const struct iovec *iov, unsigned int iov_cnt, - size_t offset, size_t bytes) -{ - size_t len; - unsigned int i, j; - for (i = 0, j = 0; i < iov_cnt && j < dst_iov_cnt && bytes; i++) { - if (offset >= iov[i].iov_len) { - offset -= iov[i].iov_len; - continue; - } - len = MIN(bytes, iov[i].iov_len - offset); - - dst_iov[j].iov_base = iov[i].iov_base + offset; - dst_iov[j].iov_len = len; - j++; - bytes -= len; - offset = 0; - } - 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_iov 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_iov 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_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; - } - assert(dst->nalloc != -1); - for (i = 0, done = 0; done < sbytes && i < src_cnt; i++) { - if (soffset < src_iov[i].iov_len) { - size_t len = MIN(src_iov[i].iov_len - soffset, sbytes - done); - qemu_iovec_add(dst, src_iov[i].iov_base + soffset, len); - done += len; - soffset = 0; - } else { - soffset -= src_iov[i].iov_len; - } - } - assert(soffset == 0); /* offset beyond end of src */ -} - -/* - * 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) -{ - qemu_iovec_concat_iov(dst, src->iov, src->niov, soffset, sbytes); -} - -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); -} - -size_t iov_discard_front(struct iovec **iov, unsigned int *iov_cnt, - size_t bytes) -{ - size_t total = 0; - struct iovec *cur; - - for (cur = *iov; *iov_cnt > 0; cur++) { - if (cur->iov_len > bytes) { - cur->iov_base += bytes; - cur->iov_len -= bytes; - total += bytes; - break; - } - - bytes -= cur->iov_len; - total += cur->iov_len; - *iov_cnt -= 1; - } - - *iov = cur; - return total; -} - -size_t iov_discard_back(struct iovec *iov, unsigned int *iov_cnt, - size_t bytes) -{ - size_t total = 0; - struct iovec *cur; - - if (*iov_cnt == 0) { - return 0; - } - - cur = iov + (*iov_cnt - 1); - - while (*iov_cnt > 0) { - if (cur->iov_len > bytes) { - cur->iov_len -= bytes; - total += bytes; - break; - } - - bytes -= cur->iov_len; - total += cur->iov_len; - cur--; - *iov_cnt -= 1; - } - - return total; -} |