--- /dev/null
+/*
+ * 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 <zlib.h>
+#include "qemu-common.h"
+#include "qemu/error-report.h"
+#include "qemu/iov.h"
+#include "qemu/sockets.h"
+#include "block/coroutine.h"
+#include "migration/migration.h"
+#include "migration/qemu-file.h"
+#include "migration/qemu-file-internal.h"
+#include "trace.h"
+
+/*
+ * Stop a file from being read/written - not all backing files can do this
+ * typically only sockets can.
+ */
+int qemu_file_shutdown(QEMUFile *f)
+{
+ if (!f->ops->shut_down) {
+ return -ENOSYS;
+ }
+ return f->ops->shut_down(f->opaque, true, true);
+}
+
+bool qemu_file_mode_is_not_valid(const char *mode)
+{
+ if (mode == NULL ||
+ (mode[0] != 'r' && mode[0] != 'w') ||
+ mode[1] != 'b' || mode[2] != 0) {
+ fprintf(stderr, "qemu_fopen: Argument validity check failed\n");
+ return true;
+ }
+
+ return false;
+}
+
+QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops)
+{
+ QEMUFile *f;
+
+ f = g_malloc0(sizeof(QEMUFile));
+
+ f->opaque = opaque;
+ f->ops = ops;
+ return f;
+}
+
+/*
+ * Get last error for stream f
+ *
+ * Return negative error value if there has been an error on previous
+ * operations, return 0 if no error happened.
+ *
+ */
+int qemu_file_get_error(QEMUFile *f)
+{
+ return f->last_error;
+}
+
+void qemu_file_set_error(QEMUFile *f, int ret)
+{
+ if (f->last_error == 0) {
+ f->last_error = ret;
+ }
+}
+
+bool qemu_file_is_writable(QEMUFile *f)
+{
+ return f->ops->writev_buffer || f->ops->put_buffer;
+}
+
+/**
+ * Flushes QEMUFile buffer
+ *
+ * If there is writev_buffer QEMUFileOps it uses it otherwise uses
+ * put_buffer ops.
+ */
+void qemu_fflush(QEMUFile *f)
+{
+ ssize_t ret = 0;
+
+ if (!qemu_file_is_writable(f)) {
+ return;
+ }
+
+ if (f->ops->writev_buffer) {
+ if (f->iovcnt > 0) {
+ ret = f->ops->writev_buffer(f->opaque, f->iov, f->iovcnt, f->pos);
+ }
+ } else {
+ if (f->buf_index > 0) {
+ ret = f->ops->put_buffer(f->opaque, f->buf, f->pos, f->buf_index);
+ }
+ }
+ if (ret >= 0) {
+ f->pos += ret;
+ }
+ f->buf_index = 0;
+ f->iovcnt = 0;
+ if (ret < 0) {
+ qemu_file_set_error(f, ret);
+ }
+}
+
+void ram_control_before_iterate(QEMUFile *f, uint64_t flags)
+{
+ int ret = 0;
+
+ if (f->ops->before_ram_iterate) {
+ ret = f->ops->before_ram_iterate(f, f->opaque, flags, NULL);
+ if (ret < 0) {
+ qemu_file_set_error(f, ret);
+ }
+ }
+}
+
+void ram_control_after_iterate(QEMUFile *f, uint64_t flags)
+{
+ int ret = 0;
+
+ if (f->ops->after_ram_iterate) {
+ ret = f->ops->after_ram_iterate(f, f->opaque, flags, NULL);
+ if (ret < 0) {
+ qemu_file_set_error(f, ret);
+ }
+ }
+}
+
+void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data)
+{
+ int ret = -EINVAL;
+
+ if (f->ops->hook_ram_load) {
+ ret = f->ops->hook_ram_load(f, f->opaque, flags, data);
+ if (ret < 0) {
+ qemu_file_set_error(f, ret);
+ }
+ } else {
+ /*
+ * Hook is a hook specifically requested by the source sending a flag
+ * that expects there to be a hook on the destination.
+ */
+ if (flags == RAM_CONTROL_HOOK) {
+ qemu_file_set_error(f, ret);
+ }
+ }
+}
+
+size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
+ ram_addr_t offset, size_t size,
+ uint64_t *bytes_sent)
+{
+ if (f->ops->save_page) {
+ int ret = f->ops->save_page(f, f->opaque, block_offset,
+ offset, size, bytes_sent);
+
+ if (ret != RAM_SAVE_CONTROL_DELAYED) {
+ if (bytes_sent && *bytes_sent > 0) {
+ qemu_update_position(f, *bytes_sent);
+ } else if (ret < 0) {
+ qemu_file_set_error(f, ret);
+ }
+ }
+
+ return ret;
+ }
+
+ return RAM_SAVE_CONTROL_NOT_SUPP;
+}
+
+/*
+ * Attempt to fill the buffer from the underlying file
+ * Returns the number of bytes read, or negative value for an error.
+ *
+ * Note that it can return a partially full buffer even in a not error/not EOF
+ * case if the underlying file descriptor gives a short read, and that can
+ * happen even on a blocking fd.
+ */
+static ssize_t qemu_fill_buffer(QEMUFile *f)
+{
+ int len;
+ int pending;
+
+ assert(!qemu_file_is_writable(f));
+
+ pending = f->buf_size - f->buf_index;
+ if (pending > 0) {
+ memmove(f->buf, f->buf + f->buf_index, pending);
+ }
+ f->buf_index = 0;
+ f->buf_size = pending;
+
+ len = f->ops->get_buffer(f->opaque, f->buf + pending, f->pos,
+ IO_BUF_SIZE - pending);
+ if (len > 0) {
+ f->buf_size += len;
+ f->pos += len;
+ } else if (len == 0) {
+ qemu_file_set_error(f, -EIO);
+ } else if (len != -EAGAIN) {
+ qemu_file_set_error(f, len);
+ }
+
+ return len;
+}
+
+int qemu_get_fd(QEMUFile *f)
+{
+ if (f->ops->get_fd) {
+ return f->ops->get_fd(f->opaque);
+ }
+ return -1;
+}
+
+void qemu_update_position(QEMUFile *f, size_t size)
+{
+ f->pos += size;
+}
+
+/** Closes the file
+ *
+ * Returns negative error value if any error happened on previous operations or
+ * while closing the file. Returns 0 or positive number on success.
+ *
+ * The meaning of return value on success depends on the specific backend
+ * being used.
+ */
+int qemu_fclose(QEMUFile *f)
+{
+ int ret;
+ qemu_fflush(f);
+ ret = qemu_file_get_error(f);
+
+ if (f->ops->close) {
+ int ret2 = f->ops->close(f->opaque);
+ if (ret >= 0) {
+ ret = ret2;
+ }
+ }
+ /* If any error was spotted before closing, we should report it
+ * instead of the close() return value.
+ */
+ if (f->last_error) {
+ ret = f->last_error;
+ }
+ g_free(f);
+ trace_qemu_file_fclose();
+ return ret;
+}
+
+static void add_to_iovec(QEMUFile *f, const uint8_t *buf, int size)
+{
+ /* check for adjacent buffer and coalesce them */
+ if (f->iovcnt > 0 && buf == f->iov[f->iovcnt - 1].iov_base +
+ f->iov[f->iovcnt - 1].iov_len) {
+ f->iov[f->iovcnt - 1].iov_len += size;
+ } else {
+ f->iov[f->iovcnt].iov_base = (uint8_t *)buf;
+ f->iov[f->iovcnt++].iov_len = size;
+ }
+
+ if (f->iovcnt >= MAX_IOV_SIZE) {
+ qemu_fflush(f);
+ }
+}
+
+void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, int size)
+{
+ if (!f->ops->writev_buffer) {
+ qemu_put_buffer(f, buf, size);
+ return;
+ }
+
+ if (f->last_error) {
+ return;
+ }
+
+ f->bytes_xfer += size;
+ add_to_iovec(f, buf, size);
+}
+
+void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size)
+{
+ int l;
+
+ if (f->last_error) {
+ return;
+ }
+
+ while (size > 0) {
+ l = IO_BUF_SIZE - f->buf_index;
+ if (l > size) {
+ l = size;
+ }
+ memcpy(f->buf + f->buf_index, buf, l);
+ f->bytes_xfer += l;
+ if (f->ops->writev_buffer) {
+ add_to_iovec(f, f->buf + f->buf_index, l);
+ }
+ f->buf_index += l;
+ if (f->buf_index == IO_BUF_SIZE) {
+ qemu_fflush(f);
+ }
+ if (qemu_file_get_error(f)) {
+ break;
+ }
+ buf += l;
+ size -= l;
+ }
+}
+
+void qemu_put_byte(QEMUFile *f, int v)
+{
+ if (f->last_error) {
+ return;
+ }
+
+ f->buf[f->buf_index] = v;
+ f->bytes_xfer++;
+ if (f->ops->writev_buffer) {
+ add_to_iovec(f, f->buf + f->buf_index, 1);
+ }
+ f->buf_index++;
+ if (f->buf_index == IO_BUF_SIZE) {
+ qemu_fflush(f);
+ }
+}
+
+void qemu_file_skip(QEMUFile *f, int size)
+{
+ if (f->buf_index + size <= f->buf_size) {
+ f->buf_index += size;
+ }
+}
+
+/*
+ * Read 'size' bytes from file (at 'offset') without moving the
+ * pointer and set 'buf' to point to that data.
+ *
+ * It will return size bytes unless there was an error, in which case it will
+ * return as many as it managed to read (assuming blocking fd's which
+ * all current QEMUFile are)
+ */
+int qemu_peek_buffer(QEMUFile *f, uint8_t **buf, int size, size_t offset)
+{
+ int pending;
+ int index;
+
+ assert(!qemu_file_is_writable(f));
+ assert(offset < IO_BUF_SIZE);
+ assert(size <= IO_BUF_SIZE - offset);
+
+ /* The 1st byte to read from */
+ index = f->buf_index + offset;
+ /* The number of available bytes starting at index */
+ pending = f->buf_size - index;
+
+ /*
+ * qemu_fill_buffer might return just a few bytes, even when there isn't
+ * an error, so loop collecting them until we get enough.
+ */
+ while (pending < size) {
+ int received = qemu_fill_buffer(f);
+
+ if (received <= 0) {
+ break;
+ }
+
+ index = f->buf_index + offset;
+ pending = f->buf_size - index;
+ }
+
+ if (pending <= 0) {
+ return 0;
+ }
+ if (size > pending) {
+ size = pending;
+ }
+
+ *buf = f->buf + index;
+ return size;
+}
+
+/*
+ * Read 'size' bytes of data from the file into buf.
+ * 'size' can be larger than the internal buffer.
+ *
+ * It will return size bytes unless there was an error, in which case it will
+ * return as many as it managed to read (assuming blocking fd's which
+ * all current QEMUFile are)
+ */
+int qemu_get_buffer(QEMUFile *f, uint8_t *buf, int size)
+{
+ int pending = size;
+ int done = 0;
+
+ while (pending > 0) {
+ int res;
+ uint8_t *src;
+
+ res = qemu_peek_buffer(f, &src, MIN(pending, IO_BUF_SIZE), 0);
+ if (res == 0) {
+ return done;
+ }
+ memcpy(buf, src, res);
+ qemu_file_skip(f, res);
+ buf += res;
+ pending -= res;
+ done += res;
+ }
+ return done;
+}
+
+/*
+ * Peeks a single byte from the buffer; this isn't guaranteed to work if
+ * offset leaves a gap after the previous read/peeked data.
+ */
+int qemu_peek_byte(QEMUFile *f, int offset)
+{
+ int index = f->buf_index + offset;
+
+ assert(!qemu_file_is_writable(f));
+ assert(offset < IO_BUF_SIZE);
+
+ if (index >= f->buf_size) {
+ qemu_fill_buffer(f);
+ index = f->buf_index + offset;
+ if (index >= f->buf_size) {
+ return 0;
+ }
+ }
+ return f->buf[index];
+}
+
+int qemu_get_byte(QEMUFile *f)
+{
+ int result;
+
+ result = qemu_peek_byte(f, 0);
+ qemu_file_skip(f, 1);
+ return result;
+}
+
+int64_t qemu_ftell_fast(QEMUFile *f)
+{
+ int64_t ret = f->pos;
+ int i;
+
+ if (f->ops->writev_buffer) {
+ for (i = 0; i < f->iovcnt; i++) {
+ ret += f->iov[i].iov_len;
+ }
+ } else {
+ ret += f->buf_index;
+ }
+
+ return ret;
+}
+
+int64_t qemu_ftell(QEMUFile *f)
+{
+ qemu_fflush(f);
+ return f->pos;
+}
+
+int qemu_file_rate_limit(QEMUFile *f)
+{
+ if (qemu_file_get_error(f)) {
+ return 1;
+ }
+ if (f->xfer_limit > 0 && f->bytes_xfer > f->xfer_limit) {
+ return 1;
+ }
+ return 0;
+}
+
+int64_t qemu_file_get_rate_limit(QEMUFile *f)
+{
+ return f->xfer_limit;
+}
+
+void qemu_file_set_rate_limit(QEMUFile *f, int64_t limit)
+{
+ f->xfer_limit = limit;
+}
+
+void qemu_file_reset_rate_limit(QEMUFile *f)
+{
+ f->bytes_xfer = 0;
+}
+
+void qemu_put_be16(QEMUFile *f, unsigned int v)
+{
+ qemu_put_byte(f, v >> 8);
+ qemu_put_byte(f, v);
+}
+
+void qemu_put_be32(QEMUFile *f, unsigned int v)
+{
+ qemu_put_byte(f, v >> 24);
+ qemu_put_byte(f, v >> 16);
+ qemu_put_byte(f, v >> 8);
+ qemu_put_byte(f, v);
+}
+
+void qemu_put_be64(QEMUFile *f, uint64_t v)
+{
+ qemu_put_be32(f, v >> 32);
+ qemu_put_be32(f, v);
+}
+
+unsigned int qemu_get_be16(QEMUFile *f)
+{
+ unsigned int v;
+ v = qemu_get_byte(f) << 8;
+ v |= qemu_get_byte(f);
+ return v;
+}
+
+unsigned int qemu_get_be32(QEMUFile *f)
+{
+ unsigned int v;
+ v = (unsigned int)qemu_get_byte(f) << 24;
+ v |= qemu_get_byte(f) << 16;
+ v |= qemu_get_byte(f) << 8;
+ v |= qemu_get_byte(f);
+ return v;
+}
+
+uint64_t qemu_get_be64(QEMUFile *f)
+{
+ uint64_t v;
+ v = (uint64_t)qemu_get_be32(f) << 32;
+ v |= qemu_get_be32(f);
+ return v;
+}
+
+/* compress size bytes of data start at p with specific compression
+ * level and store the compressed data to the buffer of f.
+ */
+
+ssize_t qemu_put_compression_data(QEMUFile *f, const uint8_t *p, size_t size,
+ int level)
+{
+ ssize_t blen = IO_BUF_SIZE - f->buf_index - sizeof(int32_t);
+
+ if (blen < compressBound(size)) {
+ return 0;
+ }
+ if (compress2(f->buf + f->buf_index + sizeof(int32_t), (uLongf *)&blen,
+ (Bytef *)p, size, level) != Z_OK) {
+ error_report("Compress Failed!");
+ return 0;
+ }
+ qemu_put_be32(f, blen);
+ f->buf_index += blen;
+ return blen + sizeof(int32_t);
+}
+
+/* Put the data in the buffer of f_src to the buffer of f_des, and
+ * then reset the buf_index of f_src to 0.
+ */
+
+int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src)
+{
+ int len = 0;
+
+ if (f_src->buf_index > 0) {
+ len = f_src->buf_index;
+ qemu_put_buffer(f_des, f_src->buf, f_src->buf_index);
+ f_src->buf_index = 0;
+ }
+ return len;
+}
+
+/*
+ * Get a string whose length is determined by a single preceding byte
+ * A preallocated 256 byte buffer must be passed in.
+ * Returns: len on success and a 0 terminated string in the buffer
+ * else 0
+ * (Note a 0 length string will return 0 either way)
+ */
+size_t qemu_get_counted_string(QEMUFile *f, char buf[256])
+{
+ size_t len = qemu_get_byte(f);
+ size_t res = qemu_get_buffer(f, (uint8_t *)buf, len);
+
+ buf[res] = 0;
+
+ return res == len ? res : 0;
+}
Code Review / kvmfornfv.git / blobdiff