diff options
Diffstat (limited to 'nbd/common.c')
-rw-r--r-- | nbd/common.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/nbd/common.c b/nbd/common.c new file mode 100644 index 0000000000..7b089b0f3b --- /dev/null +++ b/nbd/common.c @@ -0,0 +1,64 @@ +/* + * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws> + * + * Network Block Device Common Code + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; under version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#include "nbd-internal.h" + +ssize_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read) +{ + size_t offset = 0; + int err; + + if (qemu_in_coroutine()) { + if (do_read) { + return qemu_co_recv(fd, buffer, size); + } else { + return qemu_co_send(fd, buffer, size); + } + } + + while (offset < size) { + ssize_t len; + + if (do_read) { + len = qemu_recv(fd, buffer + offset, size - offset, 0); + } else { + len = send(fd, buffer + offset, size - offset, 0); + } + + if (len < 0) { + err = socket_error(); + + /* recoverable error */ + if (err == EINTR || (offset > 0 && (err == EAGAIN || err == EWOULDBLOCK))) { + continue; + } + + /* unrecoverable error */ + return -err; + } + + /* eof */ + if (len == 0) { + break; + } + + offset += len; + } + + return offset; +} |