diff options
Diffstat (limited to 'qemu-file-unix.c')
| -rw-r--r-- | qemu-file-unix.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/qemu-file-unix.c b/qemu-file-unix.c new file mode 100644 index 000000000..9682396d9 --- /dev/null +++ b/qemu-file-unix.c @@ -0,0 +1,223 @@ +/* + * QEMU System Emulator + * + * Copyright (c) 2003-2008 Fabrice Bellard + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ +#include "qemu-common.h" +#include "qemu/iov.h" +#include "qemu/sockets.h" +#include "block/coroutine.h" +#include "migration/qemu-file.h" + +typedef struct QEMUFileSocket { + int fd; + QEMUFile *file; +} QEMUFileSocket; + +static ssize_t socket_writev_buffer(void *opaque, struct iovec *iov, int iovcnt, + int64_t pos) +{ + QEMUFileSocket *s = opaque; + ssize_t len; + ssize_t size = iov_size(iov, iovcnt); + + len = iov_send(s->fd, iov, iovcnt, 0, size); + if (len < size) { + len = -socket_error(); + } + return len; +} + +static int socket_get_fd(void *opaque) +{ + QEMUFileSocket *s = opaque; + + return s->fd; +} + +static int socket_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size) +{ + QEMUFileSocket *s = opaque; + ssize_t len; + + for (;;) { + len = qemu_recv(s->fd, buf, size, 0); + if (len != -1) { + break; + } + if (socket_error() == EAGAIN) { + yield_until_fd_readable(s->fd); + } else if (socket_error() != EINTR) { + break; + } + } + + if (len == -1) { + len = -socket_error(); + } + return len; +} + +static int socket_close(void *opaque) +{ + QEMUFileSocket *s = opaque; + closesocket(s->fd); + g_free(s); + return 0; +} + +static ssize_t unix_writev_buffer(void *opaque, struct iovec *iov, int iovcnt, + int64_t pos) +{ + QEMUFileSocket *s = opaque; + ssize_t len, offset; + ssize_t size = iov_size(iov, iovcnt); + ssize_t total = 0; + + assert(iovcnt > 0); + offset = 0; + while (size > 0) { + /* Find the next start position; skip all full-sized vector elements */ + while (offset >= iov[0].iov_len) { + offset -= iov[0].iov_len; + iov++, iovcnt--; + } + + /* skip `offset' bytes from the (now) first element, undo it on exit */ + assert(iovcnt > 0); + iov[0].iov_base += offset; + iov[0].iov_len -= offset; + + do { + len = writev(s->fd, iov, iovcnt); + } while (len == -1 && errno == EINTR); + if (len == -1) { + return -errno; + } + + /* Undo the changes above */ + iov[0].iov_base -= offset; + iov[0].iov_len += offset; + + /* Prepare for the next iteration */ + offset += len; + total += len; + size -= len; + } + + return total; +} + +static int unix_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size) +{ + QEMUFileSocket *s = opaque; + ssize_t len; + + for (;;) { + len = read(s->fd, buf, size); + if (len != -1) { + break; + } + if (errno == EAGAIN) { + yield_until_fd_readable(s->fd); + } else if (errno != EINTR) { + break; + } + } + + if (len == -1) { + len = -errno; + } + return len; +} + +static int unix_close(void *opaque) +{ + QEMUFileSocket *s = opaque; + close(s->fd); + g_free(s); + return 0; +} + +static const QEMUFileOps unix_read_ops = { + .get_fd = socket_get_fd, + .get_buffer = unix_get_buffer, + .close = unix_close +}; + +static const QEMUFileOps unix_write_ops = { + .get_fd = socket_get_fd, + .writev_buffer = unix_writev_buffer, + .close = unix_close +}; + +QEMUFile *qemu_fdopen(int fd, const char *mode) +{ + QEMUFileSocket *s; + + if (mode == NULL || + (mode[0] != 'r' && mode[0] != 'w') || + mode[1] != 'b' || mode[2] != 0) { + fprintf(stderr, "qemu_fdopen: Argument validity check failed\n"); + return NULL; + } + + s = g_malloc0(sizeof(QEMUFileSocket)); + s->fd = fd; + + if (mode[0] == 'r') { + s->file = qemu_fopen_ops(s, &unix_read_ops); + } else { + s->file = qemu_fopen_ops(s, &unix_write_ops); + } + return s->file; +} + +static const QEMUFileOps socket_read_ops = { + .get_fd = socket_get_fd, + .get_buffer = socket_get_buffer, + .close = socket_close +}; + +static const QEMUFileOps socket_write_ops = { + .get_fd = socket_get_fd, + .writev_buffer = socket_writev_buffer, + .close = socket_close +}; + +QEMUFile *qemu_fopen_socket(int fd, const char *mode) +{ + QEMUFileSocket *s; + + if (qemu_file_mode_is_not_valid(mode)) { + return NULL; + } + + s = g_malloc0(sizeof(QEMUFileSocket)); + s->fd = fd; + if (mode[0] == 'w') { + qemu_set_block(s->fd); + s->file = qemu_fopen_ops(s, &socket_write_ops); + } else { + s->file = qemu_fopen_ops(s, &socket_read_ops); + } + return s->file; +} |