X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;f=savevm.c;h=31dcce975ed40827db75df2d8ef7024f022e6f97;hb=f3f4d2c09b9cf46903ba38425ec46c44185162bd;hp=4e970ca0db47ddc26300506c04d718b5848a7194;hpb=02e079c79cdb7ac8180f92edaed4b942ca6b7c71;p=qemu.git diff --git a/savevm.c b/savevm.c index 4e970ca0d..31dcce975 100644 --- a/savevm.c +++ b/savevm.c @@ -39,6 +39,7 @@ #include "qmp-commands.h" #include "trace.h" #include "qemu/bitops.h" +#include "qemu/iov.h" #define SELF_ANNOUNCE_ROUNDS 5 @@ -81,7 +82,7 @@ static void qemu_announce_self_iter(NICState *nic, void *opaque) len = announce_self_create(buf, nic->conf->macaddr.a); - qemu_send_packet_raw(&nic->nc, buf, len); + qemu_send_packet_raw(qemu_get_queue(nic), buf, len); } @@ -113,18 +114,24 @@ void qemu_announce_self(void) /* savevm/loadvm support */ #define IO_BUF_SIZE 32768 +#define MAX_IOV_SIZE MIN(IOV_MAX, 64) struct QEMUFile { const QEMUFileOps *ops; void *opaque; - int is_write; - int64_t buf_offset; /* start of buffer when writing, end of buffer - when reading */ + 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; }; @@ -140,6 +147,48 @@ typedef struct QEMUFileSocket QEMUFile *file; } QEMUFileSocket; +typedef struct { + Coroutine *co; + int fd; +} FDYieldUntilData; + +static void fd_coroutine_enter(void *opaque) +{ + FDYieldUntilData *data = opaque; + qemu_set_fd_handler(data->fd, NULL, NULL, NULL); + qemu_coroutine_enter(data->co, NULL); +} + +/** + * Yield until a file descriptor becomes readable + * + * Note that this function clobbers the handlers for the file descriptor. + */ +static void coroutine_fn yield_until_fd_readable(int fd) +{ + FDYieldUntilData data; + + assert(qemu_in_coroutine()); + data.co = qemu_coroutine_self(); + data.fd = fd; + qemu_set_fd_handler(fd, fd_coroutine_enter, NULL, &data); + qemu_coroutine_yield(); +} + +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; @@ -158,8 +207,7 @@ static int socket_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size) break; } if (socket_error() == EAGAIN) { - assert(qemu_in_coroutine()); - qemu_coroutine_yield(); + yield_until_fd_readable(s->fd); } else if (socket_error() != EINTR) { break; } @@ -205,8 +253,7 @@ static int stdio_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size) break; } if (errno == EAGAIN) { - assert(qemu_in_coroutine()); - qemu_coroutine_yield(); + yield_until_fd_readable(fileno(fp)); } else if (errno != EINTR) { break; } @@ -221,6 +268,9 @@ static int stdio_pclose(void *opaque) ret = pclose(s->stdio_file); if (ret == -1) { ret = -errno; + } else if (!WIFEXITED(ret) || WEXITSTATUS(ret) != 0) { + /* close succeeded, but non-zero exit code: */ + ret = -EIO; /* fake errno value */ } g_free(s); return ret; @@ -230,6 +280,24 @@ static int stdio_fclose(void *opaque) { QEMUFileStdio *s = opaque; int ret = 0; + + if (s->file->ops->put_buffer || s->file->ops->writev_buffer) { + int fd = fileno(s->stdio_file); + struct stat st; + + ret = fstat(fd, &st); + if (ret == 0 && S_ISREG(st.st_mode)) { + /* + * If the file handle is a regular file make sure the + * data is flushed to disk before signaling success. + */ + ret = fsync(fd); + if (ret != 0) { + ret = -errno; + return ret; + } + } + } if (fclose(s->stdio_file) == EOF) { ret = -errno; } @@ -249,11 +317,17 @@ static const QEMUFileOps stdio_pipe_write_ops = { .close = stdio_pclose }; -QEMUFile *qemu_popen(FILE *stdio_file, const char *mode) +QEMUFile *qemu_popen_cmd(const char *command, const char *mode) { + FILE *stdio_file; QEMUFileStdio *s; - if (stdio_file == NULL || mode == NULL || (mode[0] != 'r' && mode[0] != 'w') || mode[1] != 0) { + stdio_file = popen(command, mode); + if (stdio_file == NULL) { + return NULL; + } + + if (mode == NULL || (mode[0] != 'r' && mode[0] != 'w') || mode[1] != 0) { fprintf(stderr, "qemu_popen: Argument validity check failed\n"); return NULL; } @@ -270,18 +344,6 @@ QEMUFile *qemu_popen(FILE *stdio_file, const char *mode) return s->file; } -QEMUFile *qemu_popen_cmd(const char *command, const char *mode) -{ - FILE *popen_file; - - popen_file = popen(command, mode); - if(popen_file == NULL) { - return NULL; - } - - return qemu_popen(popen_file, mode); -} - static const QEMUFileOps stdio_file_read_ops = { .get_fd = stdio_get_fd, .get_buffer = stdio_get_buffer, @@ -294,9 +356,94 @@ static const QEMUFileOps stdio_file_write_ops = { .close = stdio_fclose }; +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) { - QEMUFileStdio *s; + QEMUFileSocket *s; if (mode == NULL || (mode[0] != 'r' && mode[0] != 'w') || @@ -305,21 +452,15 @@ QEMUFile *qemu_fdopen(int fd, const char *mode) return NULL; } - s = g_malloc0(sizeof(QEMUFileStdio)); - s->stdio_file = fdopen(fd, mode); - if (!s->stdio_file) - goto fail; + s = g_malloc0(sizeof(QEMUFileSocket)); + s->fd = fd; if(mode[0] == 'r') { - s->file = qemu_fopen_ops(s, &stdio_file_read_ops); + s->file = qemu_fopen_ops(s, &unix_read_ops); } else { - s->file = qemu_fopen_ops(s, &stdio_file_write_ops); + s->file = qemu_fopen_ops(s, &unix_write_ops); } return s->file; - -fail: - g_free(s); - return NULL; } static const QEMUFileOps socket_read_ops = { @@ -328,12 +469,30 @@ static const QEMUFileOps socket_read_ops = { .close = socket_close }; -QEMUFile *qemu_fopen_socket(int fd) +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 = g_malloc0(sizeof(QEMUFileSocket)); + 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 NULL; + } + s->fd = fd; - s->file = qemu_fopen_ops(s, &socket_read_ops); + 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; } @@ -365,6 +524,21 @@ fail: return NULL; } +static ssize_t block_writev_buffer(void *opaque, struct iovec *iov, int iovcnt, + int64_t pos) +{ + int ret; + QEMUIOVector qiov; + + qemu_iovec_init_external(&qiov, iov, iovcnt); + ret = bdrv_writev_vmstate(opaque, &qiov, pos); + if (ret < 0) { + return ret; + } + + return qiov.size; +} + static int block_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, int size) { @@ -388,8 +562,9 @@ static const QEMUFileOps bdrv_read_ops = { }; static const QEMUFileOps bdrv_write_ops = { - .put_buffer = block_put_buffer, - .close = bdrv_fclose + .put_buffer = block_put_buffer, + .writev_buffer = block_writev_buffer, + .close = bdrv_fclose }; static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int is_writable) @@ -407,8 +582,6 @@ QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops) f->opaque = opaque; f->ops = ops; - f->is_write = 0; - return f; } @@ -419,27 +592,47 @@ int qemu_file_get_error(QEMUFile *f) static void qemu_file_set_error(QEMUFile *f, int ret) { - f->last_error = ret; + if (f->last_error == 0) { + f->last_error = ret; + } } -/** Flushes QEMUFile buffer +static inline 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. */ -static int qemu_fflush(QEMUFile *f) +static void qemu_fflush(QEMUFile *f) { - int ret = 0; + ssize_t ret = 0; - if (!f->ops->put_buffer) - return 0; + if (!qemu_file_is_writable(f)) { + return; + } - if (f->is_write && f->buf_index > 0) { - ret = f->ops->put_buffer(f->opaque, f->buf, f->buf_offset, f->buf_index); - if (ret >= 0) { - f->buf_offset += f->buf_index; + 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); } - f->buf_index = 0; } - return ret; + if (ret >= 0) { + f->pos += ret; + } + f->buf_index = 0; + f->iovcnt = 0; + if (ret < 0) { + qemu_file_set_error(f, ret); + } } static void qemu_fill_buffer(QEMUFile *f) @@ -447,11 +640,7 @@ static void qemu_fill_buffer(QEMUFile *f) int len; int pending; - if (!f->ops->get_buffer) - return; - - if (f->is_write) - abort(); + assert(!qemu_file_is_writable(f)); pending = f->buf_size - f->buf_index; if (pending > 0) { @@ -460,11 +649,11 @@ static void qemu_fill_buffer(QEMUFile *f) f->buf_index = 0; f->buf_size = pending; - len = f->ops->get_buffer(f->opaque, f->buf + pending, f->buf_offset, + len = f->ops->get_buffer(f->opaque, f->buf + pending, f->pos, IO_BUF_SIZE - pending); if (len > 0) { f->buf_size += len; - f->buf_offset += len; + f->pos += len; } else if (len == 0) { qemu_file_set_error(f, -EIO); } else if (len != -EAGAIN) @@ -490,7 +679,8 @@ int qemu_get_fd(QEMUFile *f) int qemu_fclose(QEMUFile *f) { int ret; - ret = qemu_fflush(f); + qemu_fflush(f); + ret = qemu_file_get_error(f); if (f->ops->close) { int ret2 = f->ops->close(f->opaque); @@ -508,18 +698,43 @@ int qemu_fclose(QEMUFile *f) return ret; } -void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size) +static void add_to_iovec(QEMUFile *f, const uint8_t *buf, int size) { - int l; + /* 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; } - if (f->is_write == 0 && f->buf_index > 0) { - fprintf(stderr, - "Attempted to write to buffer while read buffer is not empty\n"); - abort(); + 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) { @@ -527,17 +742,19 @@ void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size) if (l > size) l = size; memcpy(f->buf + f->buf_index, buf, l); - f->is_write = 1; + f->bytes_xfer += size; + 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; - if (f->buf_index >= IO_BUF_SIZE) { - int ret = qemu_fflush(f); - if (ret < 0) { - qemu_file_set_error(f, ret); - break; - } - } } } @@ -547,19 +764,14 @@ void qemu_put_byte(QEMUFile *f, int v) return; } - if (f->is_write == 0 && f->buf_index > 0) { - fprintf(stderr, - "Attempted to write to buffer while read buffer is not empty\n"); - abort(); + 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[f->buf_index++] = v; - f->is_write = 1; - if (f->buf_index >= IO_BUF_SIZE) { - int ret = qemu_fflush(f); - if (ret < 0) { - qemu_file_set_error(f, ret); - } + f->buf_index++; + if (f->buf_index == IO_BUF_SIZE) { + qemu_fflush(f); } } @@ -575,9 +787,7 @@ static int qemu_peek_buffer(QEMUFile *f, uint8_t *buf, int size, size_t offset) int pending; int index; - if (f->is_write) { - abort(); - } + assert(!qemu_file_is_writable(f)); index = f->buf_index + offset; pending = f->buf_size - index; @@ -622,9 +832,7 @@ static int qemu_peek_byte(QEMUFile *f, int offset) { int index = f->buf_index + offset; - if (f->is_write) { - abort(); - } + assert(!qemu_file_is_writable(f)); if (index >= f->buf_size) { qemu_fill_buffer(f); @@ -645,35 +853,36 @@ int qemu_get_byte(QEMUFile *f) return result; } -static int64_t qemu_ftell(QEMUFile *f) +int64_t qemu_ftell(QEMUFile *f) { - return f->buf_offset - f->buf_size + f->buf_index; + qemu_fflush(f); + return f->pos; } int qemu_file_rate_limit(QEMUFile *f) { - if (f->ops->rate_limit) - return f->ops->rate_limit(f->opaque); - + 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) { - if (f->ops->get_rate_limit) - return f->ops->get_rate_limit(f->opaque); - - return 0; + return f->xfer_limit; } -int64_t qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate) +void qemu_file_set_rate_limit(QEMUFile *f, int64_t limit) { - /* any failed or completed migration keeps its state to allow probing of - * migration data, but has no associated file anymore */ - if (f && f->ops->set_rate_limit) - return f->ops->set_rate_limit(f->opaque, new_rate); + f->xfer_limit = limit; +} - return 0; +void qemu_file_reset_rate_limit(QEMUFile *f) +{ + f->bytes_xfer = 0; } void qemu_put_be16(QEMUFile *f, unsigned int v) @@ -996,6 +1205,27 @@ const VMStateInfo vmstate_info_uint64 = { .put = put_uint64, }; +/* 64 bit unsigned int. See that the received value is the same than the one + in the field */ + +static int get_uint64_equal(QEMUFile *f, void *pv, size_t size) +{ + uint64_t *v = pv; + uint64_t v2; + qemu_get_be64s(f, &v2); + + if (*v == v2) { + return 0; + } + return -EINVAL; +} + +const VMStateInfo vmstate_info_uint64_equal = { + .name = "int64 equal", + .get = get_uint64_equal, + .put = put_uint64, +}; + /* 8 bit int. See that the received value is the same than the one in the field */ @@ -1036,6 +1266,29 @@ const VMStateInfo vmstate_info_uint16_equal = { .put = put_uint16, }; +/* floating point */ + +static int get_float64(QEMUFile *f, void *pv, size_t size) +{ + float64 *v = pv; + + *v = make_float64(qemu_get_be64(f)); + return 0; +} + +static void put_float64(QEMUFile *f, void *pv, size_t size) +{ + uint64_t *v = pv; + + qemu_put_be64(f, float64_val(*v)); +} + +const VMStateInfo vmstate_info_float64 = { + .name = "float64", + .get = get_float64, + .put = put_float64, +}; + /* timers */ static int get_timer(QEMUFile *f, void *pv, size_t size) @@ -1347,13 +1600,6 @@ int vmstate_register_with_alias_id(DeviceState *dev, int instance_id, return 0; } -int vmstate_register(DeviceState *dev, int instance_id, - const VMStateDescription *vmsd, void *opaque) -{ - return vmstate_register_with_alias_id(dev, instance_id, vmsd, - opaque, -1, 0); -} - void vmstate_unregister(DeviceState *dev, const VMStateDescription *vmsd, void *opaque) { @@ -1547,8 +1793,8 @@ bool qemu_savevm_state_blocked(Error **errp) return false; } -int qemu_savevm_state_begin(QEMUFile *f, - const MigrationParams *params) +void qemu_savevm_state_begin(QEMUFile *f, + const MigrationParams *params) { SaveStateEntry *se; int ret; @@ -1588,17 +1834,10 @@ int qemu_savevm_state_begin(QEMUFile *f, ret = se->ops->save_live_setup(f, se->opaque); if (ret < 0) { - qemu_savevm_state_cancel(f); - return ret; + qemu_file_set_error(f, ret); + break; } } - ret = qemu_file_get_error(f); - if (ret != 0) { - qemu_savevm_state_cancel(f); - } - - return ret; - } /* @@ -1632,6 +1871,9 @@ int qemu_savevm_state_iterate(QEMUFile *f) ret = se->ops->save_live_iterate(f, se->opaque); trace_savevm_section_end(se->section_id); + if (ret < 0) { + qemu_file_set_error(f, ret); + } if (ret <= 0) { /* Do not proceed to the next vmstate before this one reported completion of the current stage. This serializes the migration @@ -1640,17 +1882,10 @@ int qemu_savevm_state_iterate(QEMUFile *f) break; } } - if (ret != 0) { - return ret; - } - ret = qemu_file_get_error(f); - if (ret != 0) { - qemu_savevm_state_cancel(f); - } return ret; } -int qemu_savevm_state_complete(QEMUFile *f) +void qemu_savevm_state_complete(QEMUFile *f) { SaveStateEntry *se; int ret; @@ -1674,7 +1909,8 @@ int qemu_savevm_state_complete(QEMUFile *f) ret = se->ops->save_live_complete(f, se->opaque); trace_savevm_section_end(se->section_id); if (ret < 0) { - return ret; + qemu_file_set_error(f, ret); + return; } } @@ -1702,8 +1938,7 @@ int qemu_savevm_state_complete(QEMUFile *f) } qemu_put_byte(f, QEMU_VM_EOF); - - return qemu_file_get_error(f); + qemu_fflush(f); } uint64_t qemu_savevm_state_pending(QEMUFile *f, uint64_t max_size) @@ -1725,7 +1960,7 @@ uint64_t qemu_savevm_state_pending(QEMUFile *f, uint64_t max_size) return ret; } -void qemu_savevm_state_cancel(QEMUFile *f) +void qemu_savevm_state_cancel(void) { SaveStateEntry *se; @@ -1745,27 +1980,27 @@ static int qemu_savevm_state(QEMUFile *f) }; if (qemu_savevm_state_blocked(NULL)) { - ret = -EINVAL; - goto out; + return -EINVAL; } - ret = qemu_savevm_state_begin(f, ¶ms); - if (ret < 0) - goto out; - - do { - ret = qemu_savevm_state_iterate(f); - if (ret < 0) - goto out; - } while (ret == 0); + qemu_mutex_unlock_iothread(); + qemu_savevm_state_begin(f, ¶ms); + qemu_mutex_lock_iothread(); - ret = qemu_savevm_state_complete(f); + while (qemu_file_get_error(f) == 0) { + if (qemu_savevm_state_iterate(f) > 0) { + break; + } + } -out: + ret = qemu_file_get_error(f); if (ret == 0) { + qemu_savevm_state_complete(f); ret = qemu_file_get_error(f); } - + if (ret != 0) { + qemu_savevm_state_cancel(); + } return ret; } @@ -2307,7 +2542,7 @@ void do_delvm(Monitor *mon, const QDict *qdict) } } -void do_info_snapshots(Monitor *mon) +void do_info_snapshots(Monitor *mon, const QDict *qdict) { BlockDriverState *bs, *bs1; QEMUSnapshotInfo *sn_tab, *sn, s, *sn_info = &s; @@ -2386,162 +2621,3 @@ void vmstate_register_ram_global(MemoryRegion *mr) { vmstate_register_ram(mr, NULL); } - -/* - page = zrun nzrun - | zrun nzrun page - - zrun = length - - nzrun = length byte... - - length = uleb128 encoded integer - */ -int xbzrle_encode_buffer(uint8_t *old_buf, uint8_t *new_buf, int slen, - uint8_t *dst, int dlen) -{ - uint32_t zrun_len = 0, nzrun_len = 0; - int d = 0, i = 0; - long res, xor; - uint8_t *nzrun_start = NULL; - - g_assert(!(((uintptr_t)old_buf | (uintptr_t)new_buf | slen) % - sizeof(long))); - - while (i < slen) { - /* overflow */ - if (d + 2 > dlen) { - return -1; - } - - /* not aligned to sizeof(long) */ - res = (slen - i) % sizeof(long); - while (res && old_buf[i] == new_buf[i]) { - zrun_len++; - i++; - res--; - } - - /* word at a time for speed */ - if (!res) { - while (i < slen && - (*(long *)(old_buf + i)) == (*(long *)(new_buf + i))) { - i += sizeof(long); - zrun_len += sizeof(long); - } - - /* go over the rest */ - while (i < slen && old_buf[i] == new_buf[i]) { - zrun_len++; - i++; - } - } - - /* buffer unchanged */ - if (zrun_len == slen) { - return 0; - } - - /* skip last zero run */ - if (i == slen) { - return d; - } - - d += uleb128_encode_small(dst + d, zrun_len); - - zrun_len = 0; - nzrun_start = new_buf + i; - - /* overflow */ - if (d + 2 > dlen) { - return -1; - } - /* not aligned to sizeof(long) */ - res = (slen - i) % sizeof(long); - while (res && old_buf[i] != new_buf[i]) { - i++; - nzrun_len++; - res--; - } - - /* word at a time for speed, use of 32-bit long okay */ - if (!res) { - /* truncation to 32-bit long okay */ - long mask = (long)0x0101010101010101ULL; - while (i < slen) { - xor = *(long *)(old_buf + i) ^ *(long *)(new_buf + i); - if ((xor - mask) & ~xor & (mask << 7)) { - /* found the end of an nzrun within the current long */ - while (old_buf[i] != new_buf[i]) { - nzrun_len++; - i++; - } - break; - } else { - i += sizeof(long); - nzrun_len += sizeof(long); - } - } - } - - d += uleb128_encode_small(dst + d, nzrun_len); - /* overflow */ - if (d + nzrun_len > dlen) { - return -1; - } - memcpy(dst + d, nzrun_start, nzrun_len); - d += nzrun_len; - nzrun_len = 0; - } - - return d; -} - -int xbzrle_decode_buffer(uint8_t *src, int slen, uint8_t *dst, int dlen) -{ - int i = 0, d = 0; - int ret; - uint32_t count = 0; - - while (i < slen) { - - /* zrun */ - if ((slen - i) < 2) { - return -1; - } - - ret = uleb128_decode_small(src + i, &count); - if (ret < 0 || (i && !count)) { - return -1; - } - i += ret; - d += count; - - /* overflow */ - if (d > dlen) { - return -1; - } - - /* nzrun */ - if ((slen - i) < 2) { - return -1; - } - - ret = uleb128_decode_small(src + i, &count); - if (ret < 0 || !count) { - return -1; - } - i += ret; - - /* overflow */ - if (d + count > dlen || i + count > slen) { - return -1; - } - - memcpy(dst + d, src + i, count); - d += count; - i += count; - } - - return d; -}