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authorDr. David Alan Gilbert <dgilbert@redhat.com>2014-12-12 11:13:38 +0000
committerAmit Shah <amit.shah@redhat.com>2014-12-16 17:47:36 +0530
commit60fe637bf0e4d7989e21e50f52526444765c63b4 (patch)
treeb5dbcea1d25fe151e097cc1401cb19b64262401c /qemu-file.c
parentd6d69731f5295e4c3bb0196f57e8848af28b705e (diff)
downloadqemu-60fe637bf0e4d7989e21e50f52526444765c63b4.tar.gz
Start migrating migration code into a migration directory
The migration code now occupies a fair chunk of the top level .c files, it seems time to give it it's own directory. I've not touched: arch_init.c - that's mostly RAM migration but has a few random other bits savevm.c - because it's built target specific This is purely a code move; no code has changed. - it fails checkpatch because of old violations, it feels safer to keep this as purely a move and fix those at some mythical future date. The xbzrle and vmstate tests are now only run for softmmu builds since they require files in the migrate/ directory which is only built for softmmu. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com>
Diffstat (limited to 'qemu-file.c')
-rw-r--r--qemu-file.c995
1 files changed, 0 insertions, 995 deletions
diff --git a/qemu-file.c b/qemu-file.c
deleted file mode 100644
index f938e36fe8..0000000000
--- a/qemu-file.c
+++ /dev/null
@@ -1,995 +0,0 @@
-/*
- * 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/migration.h"
-#include "migration/qemu-file.h"
-#include "trace.h"
-
-#define IO_BUF_SIZE 32768
-#define MAX_IOV_SIZE MIN(IOV_MAX, 64)
-
-struct QEMUFile {
- const QEMUFileOps *ops;
- void *opaque;
-
- int64_t bytes_xfer;
- int64_t xfer_limit;
-
- int64_t pos; /* start of buffer when writing, end of buffer
- when reading */
- int buf_index;
- int buf_size; /* 0 when writing */
- uint8_t buf[IO_BUF_SIZE];
-
- struct iovec iov[MAX_IOV_SIZE];
- unsigned int iovcnt;
-
- int last_error;
-};
-
-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);
- 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);
- if (ret < 0) {
- qemu_file_set_error(f, ret);
- }
- }
-}
-
-void ram_control_load_hook(QEMUFile *f, uint64_t flags)
-{
- int ret = -EINVAL;
-
- if (f->ops->hook_ram_load) {
- ret = f->ops->hook_ram_load(f, f->opaque, flags);
- if (ret < 0) {
- qemu_file_set_error(f, ret);
- }
- } else {
- 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, int *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') into buf without moving the
- * pointer.
- *
- * 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;
- }
-
- memcpy(buf, f->buf + index, size);
- 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;
-
- res = qemu_peek_buffer(f, buf, MIN(pending, IO_BUF_SIZE), 0);
- if (res == 0) {
- return done;
- }
- 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(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 = 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;
-}
-
-#define QSB_CHUNK_SIZE (1 << 10)
-#define QSB_MAX_CHUNK_SIZE (16 * QSB_CHUNK_SIZE)
-
-/**
- * Create a QEMUSizedBuffer
- * This type of buffer uses scatter-gather lists internally and
- * can grow to any size. Any data array in the scatter-gather list
- * can hold different amount of bytes.
- *
- * @buffer: Optional buffer to copy into the QSB
- * @len: size of initial buffer; if @buffer is given, buffer must
- * hold at least len bytes
- *
- * Returns a pointer to a QEMUSizedBuffer or NULL on allocation failure
- */
-QEMUSizedBuffer *qsb_create(const uint8_t *buffer, size_t len)
-{
- QEMUSizedBuffer *qsb;
- size_t alloc_len, num_chunks, i, to_copy;
- size_t chunk_size = (len > QSB_MAX_CHUNK_SIZE)
- ? QSB_MAX_CHUNK_SIZE
- : QSB_CHUNK_SIZE;
-
- num_chunks = DIV_ROUND_UP(len ? len : QSB_CHUNK_SIZE, chunk_size);
- alloc_len = num_chunks * chunk_size;
-
- qsb = g_try_new0(QEMUSizedBuffer, 1);
- if (!qsb) {
- return NULL;
- }
-
- qsb->iov = g_try_new0(struct iovec, num_chunks);
- if (!qsb->iov) {
- g_free(qsb);
- return NULL;
- }
-
- qsb->n_iov = num_chunks;
-
- for (i = 0; i < num_chunks; i++) {
- qsb->iov[i].iov_base = g_try_malloc0(chunk_size);
- if (!qsb->iov[i].iov_base) {
- /* qsb_free is safe since g_free can cope with NULL */
- qsb_free(qsb);
- return NULL;
- }
-
- qsb->iov[i].iov_len = chunk_size;
- if (buffer) {
- to_copy = (len - qsb->used) > chunk_size
- ? chunk_size : (len - qsb->used);
- memcpy(qsb->iov[i].iov_base, &buffer[qsb->used], to_copy);
- qsb->used += to_copy;
- }
- }
-
- qsb->size = alloc_len;
-
- return qsb;
-}
-
-/**
- * Free the QEMUSizedBuffer
- *
- * @qsb: The QEMUSizedBuffer to free
- */
-void qsb_free(QEMUSizedBuffer *qsb)
-{
- size_t i;
-
- if (!qsb) {
- return;
- }
-
- for (i = 0; i < qsb->n_iov; i++) {
- g_free(qsb->iov[i].iov_base);
- }
- g_free(qsb->iov);
- g_free(qsb);
-}
-
-/**
- * Get the number of used bytes in the QEMUSizedBuffer
- *
- * @qsb: A QEMUSizedBuffer
- *
- * Returns the number of bytes currently used in this buffer
- */
-size_t qsb_get_length(const QEMUSizedBuffer *qsb)
-{
- return qsb->used;
-}
-
-/**
- * Set the length of the buffer; the primary usage of this
- * function is to truncate the number of used bytes in the buffer.
- * The size will not be extended beyond the current number of
- * allocated bytes in the QEMUSizedBuffer.
- *
- * @qsb: A QEMUSizedBuffer
- * @new_len: The new length of bytes in the buffer
- *
- * Returns the number of bytes the buffer was truncated or extended
- * to.
- */
-size_t qsb_set_length(QEMUSizedBuffer *qsb, size_t new_len)
-{
- if (new_len <= qsb->size) {
- qsb->used = new_len;
- } else {
- qsb->used = qsb->size;
- }
- return qsb->used;
-}
-
-/**
- * Get the iovec that holds the data for a given position @pos.
- *
- * @qsb: A QEMUSizedBuffer
- * @pos: The index of a byte in the buffer
- * @d_off: Pointer to an offset that this function will indicate
- * at what position within the returned iovec the byte
- * is to be found
- *
- * Returns the index of the iovec that holds the byte at the given
- * index @pos in the byte stream; a negative number if the iovec
- * for the given position @pos does not exist.
- */
-static ssize_t qsb_get_iovec(const QEMUSizedBuffer *qsb,
- off_t pos, off_t *d_off)
-{
- ssize_t i;
- off_t curr = 0;
-
- if (pos > qsb->used) {
- return -1;
- }
-
- for (i = 0; i < qsb->n_iov; i++) {
- if (curr + qsb->iov[i].iov_len > pos) {
- *d_off = pos - curr;
- return i;
- }
- curr += qsb->iov[i].iov_len;
- }
- return -1;
-}
-
-/*
- * Convert the QEMUSizedBuffer into a flat buffer.
- *
- * Note: If at all possible, try to avoid this function since it
- * may unnecessarily copy memory around.
- *
- * @qsb: pointer to QEMUSizedBuffer
- * @start: offset to start at
- * @count: number of bytes to copy
- * @buf: a pointer to a buffer to write into (at least @count bytes)
- *
- * Returns the number of bytes copied into the output buffer
- */
-ssize_t qsb_get_buffer(const QEMUSizedBuffer *qsb, off_t start,
- size_t count, uint8_t *buffer)
-{
- const struct iovec *iov;
- size_t to_copy, all_copy;
- ssize_t index;
- off_t s_off;
- off_t d_off = 0;
- char *s;
-
- if (start > qsb->used) {
- return 0;
- }
-
- all_copy = qsb->used - start;
- if (all_copy > count) {
- all_copy = count;
- } else {
- count = all_copy;
- }
-
- index = qsb_get_iovec(qsb, start, &s_off);
- if (index < 0) {
- return 0;
- }
-
- while (all_copy > 0) {
- iov = &qsb->iov[index];
-
- s = iov->iov_base;
-
- to_copy = iov->iov_len - s_off;
- if (to_copy > all_copy) {
- to_copy = all_copy;
- }
- memcpy(&buffer[d_off], &s[s_off], to_copy);
-
- d_off += to_copy;
- all_copy -= to_copy;
-
- s_off = 0;
- index++;
- }
-
- return count;
-}
-
-/**
- * Grow the QEMUSizedBuffer to the given size and allocate
- * memory for it.
- *
- * @qsb: A QEMUSizedBuffer
- * @new_size: The new size of the buffer
- *
- * Return:
- * a negative error code in case of memory allocation failure
- * or
- * the new size of the buffer. The returned size may be greater or equal
- * to @new_size.
- */
-static ssize_t qsb_grow(QEMUSizedBuffer *qsb, size_t new_size)
-{
- size_t needed_chunks, i;
-
- if (qsb->size < new_size) {
- struct iovec *new_iov;
- size_t size_diff = new_size - qsb->size;
- size_t chunk_size = (size_diff > QSB_MAX_CHUNK_SIZE)
- ? QSB_MAX_CHUNK_SIZE : QSB_CHUNK_SIZE;
-
- needed_chunks = DIV_ROUND_UP(size_diff, chunk_size);
-
- new_iov = g_try_new(struct iovec, qsb->n_iov + needed_chunks);
- if (new_iov == NULL) {
- return -ENOMEM;
- }
-
- /* Allocate new chunks as needed into new_iov */
- for (i = qsb->n_iov; i < qsb->n_iov + needed_chunks; i++) {
- new_iov[i].iov_base = g_try_malloc0(chunk_size);
- new_iov[i].iov_len = chunk_size;
- if (!new_iov[i].iov_base) {
- size_t j;
-
- /* Free previously allocated new chunks */
- for (j = qsb->n_iov; j < i; j++) {
- g_free(new_iov[j].iov_base);
- }
- g_free(new_iov);
-
- return -ENOMEM;
- }
- }
-
- /*
- * Now we can't get any allocation errors, copy over to new iov
- * and switch.
- */
- for (i = 0; i < qsb->n_iov; i++) {
- new_iov[i] = qsb->iov[i];
- }
-
- qsb->n_iov += needed_chunks;
- g_free(qsb->iov);
- qsb->iov = new_iov;
- qsb->size += (needed_chunks * chunk_size);
- }
-
- return qsb->size;
-}
-
-/**
- * Write into the QEMUSizedBuffer at a given position and a given
- * number of bytes. This function will automatically grow the
- * QEMUSizedBuffer.
- *
- * @qsb: A QEMUSizedBuffer
- * @source: A byte array to copy data from
- * @pos: The position within the @qsb to write data to
- * @size: The number of bytes to copy into the @qsb
- *
- * Returns @size or a negative error code in case of memory allocation failure,
- * or with an invalid 'pos'
- */
-ssize_t qsb_write_at(QEMUSizedBuffer *qsb, const uint8_t *source,
- off_t pos, size_t count)
-{
- ssize_t rc = qsb_grow(qsb, pos + count);
- size_t to_copy;
- size_t all_copy = count;
- const struct iovec *iov;
- ssize_t index;
- char *dest;
- off_t d_off, s_off = 0;
-
- if (rc < 0) {
- return rc;
- }
-
- if (pos + count > qsb->used) {
- qsb->used = pos + count;
- }
-
- index = qsb_get_iovec(qsb, pos, &d_off);
- if (index < 0) {
- return -EINVAL;
- }
-
- while (all_copy > 0) {
- iov = &qsb->iov[index];
-
- dest = iov->iov_base;
-
- to_copy = iov->iov_len - d_off;
- if (to_copy > all_copy) {
- to_copy = all_copy;
- }
-
- memcpy(&dest[d_off], &source[s_off], to_copy);
-
- s_off += to_copy;
- all_copy -= to_copy;
-
- d_off = 0;
- index++;
- }
-
- return count;
-}
-
-/**
- * Create a deep copy of the given QEMUSizedBuffer.
- *
- * @qsb: A QEMUSizedBuffer
- *
- * Returns a clone of @qsb or NULL on allocation failure
- */
-QEMUSizedBuffer *qsb_clone(const QEMUSizedBuffer *qsb)
-{
- QEMUSizedBuffer *out = qsb_create(NULL, qsb_get_length(qsb));
- size_t i;
- ssize_t res;
- off_t pos = 0;
-
- if (!out) {
- return NULL;
- }
-
- for (i = 0; i < qsb->n_iov; i++) {
- res = qsb_write_at(out, qsb->iov[i].iov_base,
- pos, qsb->iov[i].iov_len);
- if (res < 0) {
- qsb_free(out);
- return NULL;
- }
- pos += res;
- }
-
- return out;
-}
-
-typedef struct QEMUBuffer {
- QEMUSizedBuffer *qsb;
- QEMUFile *file;
-} QEMUBuffer;
-
-static int buf_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
-{
- QEMUBuffer *s = opaque;
- ssize_t len = qsb_get_length(s->qsb) - pos;
-
- if (len <= 0) {
- return 0;
- }
-
- if (len > size) {
- len = size;
- }
- return qsb_get_buffer(s->qsb, pos, len, buf);
-}
-
-static int buf_put_buffer(void *opaque, const uint8_t *buf,
- int64_t pos, int size)
-{
- QEMUBuffer *s = opaque;
-
- return qsb_write_at(s->qsb, buf, pos, size);
-}
-
-static int buf_close(void *opaque)
-{
- QEMUBuffer *s = opaque;
-
- qsb_free(s->qsb);
-
- g_free(s);
-
- return 0;
-}
-
-const QEMUSizedBuffer *qemu_buf_get(QEMUFile *f)
-{
- QEMUBuffer *p;
-
- qemu_fflush(f);
-
- p = f->opaque;
-
- return p->qsb;
-}
-
-static const QEMUFileOps buf_read_ops = {
- .get_buffer = buf_get_buffer,
- .close = buf_close,
-};
-
-static const QEMUFileOps buf_write_ops = {
- .put_buffer = buf_put_buffer,
- .close = buf_close,
-};
-
-QEMUFile *qemu_bufopen(const char *mode, QEMUSizedBuffer *input)
-{
- QEMUBuffer *s;
-
- if (mode == NULL || (mode[0] != 'r' && mode[0] != 'w') ||
- mode[1] != '\0') {
- error_report("qemu_bufopen: Argument validity check failed");
- return NULL;
- }
-
- s = g_malloc0(sizeof(QEMUBuffer));
- if (mode[0] == 'r') {
- s->qsb = input;
- }
-
- if (s->qsb == NULL) {
- s->qsb = qsb_create(NULL, 0);
- }
- if (!s->qsb) {
- g_free(s);
- error_report("qemu_bufopen: qsb_create failed");
- return NULL;
- }
-
-
- if (mode[0] == 'r') {
- s->file = qemu_fopen_ops(s, &buf_read_ops);
- } else {
- s->file = qemu_fopen_ops(s, &buf_write_ops);
- }
- return s->file;
-}