+/*

+ zip_source_buffer.c -- create zip data source from buffer

+ Copyright (C) 1999-2016 Dieter Baron and Thomas Klausner

+

+ This file is part of libzip, a library to manipulate ZIP archives.

+ The authors can be contacted at <libzip@nih.at>

+

+ Redistribution and use in source and binary forms, with or without

+ modification, are permitted provided that the following conditions

+ are met:

+ 1. Redistributions of source code must retain the above copyright

+ notice, this list of conditions and the following disclaimer.

+ 2. Redistributions in binary form must reproduce the above copyright

+ notice, this list of conditions and the following disclaimer in

+ the documentation and/or other materials provided with the

+ distribution.

+ 3. The names of the authors may not be used to endorse or promote

+ products derived from this software without specific prior

+ written permission.

+

+ THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS

+ OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

+ WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

+ ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY

+ DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

+ DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE

+ GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

+ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER

+ IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR

+ OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN

+ IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

+*/

+

+#include <stdlib.h>

+#include <string.h>

+

+#include "zipint.h"

+

+#ifndef WRITE_FRAGMENT_SIZE

+#define WRITE_FRAGMENT_SIZE 64*1024

+#endif

+

+struct buffer {

+ zip_uint64_t fragment_size; /* size of each fragment */

+

+ zip_uint8_t **fragments; /* pointers to fragments */

+ zip_uint64_t nfragments; /* number of allocated fragments */

+ zip_uint64_t fragments_capacity; /* size of fragments (number of pointers) */

+ zip_uint64_t size; /* size of data in bytes */

+ zip_uint64_t offset; /* current offset */

+ int free_data;

+};

+

+typedef struct buffer buffer_t;

+

+struct read_data {

+ zip_error_t error;

+ time_t mtime;

+ buffer_t *in;

+ buffer_t *out;

+};

+

+static void buffer_free(buffer_t *buffer);

+static buffer_t *buffer_new(zip_uint64_t fragment_size);

+static buffer_t *buffer_new_read(const void *data, zip_uint64_t length, int free_data);

+static buffer_t *buffer_new_write(zip_uint64_t fragment_size);

+static zip_int64_t buffer_read(buffer_t *buffer, zip_uint8_t *data, zip_uint64_t length);

+static int buffer_seek(buffer_t *buffer, void *data, zip_uint64_t len, zip_error_t *error);

+static zip_int64_t buffer_write(buffer_t *buffer, const zip_uint8_t *data, zip_uint64_t length, zip_error_t *);

+

+static zip_int64_t read_data(void *, void *, zip_uint64_t, zip_source_cmd_t);

+

+

+ZIP_EXTERN zip_source_t *

+zip_source_buffer(zip_t *za, const void *data, zip_uint64_t len, int freep)

+{

+ if (za == NULL)

+ return NULL;

+

+ return zip_source_buffer_create(data, len, freep, &za->error);

+}

+

+

+ZIP_EXTERN zip_source_t *

+zip_source_buffer_create(const void *data, zip_uint64_t len, int freep, zip_error_t *error)

+{

+ struct read_data *ctx;

+ zip_source_t *zs;

+

+ if (data == NULL && len > 0) {

+ zip_error_set(error, ZIP_ER_INVAL, 0);

+ return NULL;

+ }

+

+ if ((ctx=(struct read_data *)malloc(sizeof(*ctx))) == NULL) {

+ zip_error_set(error, ZIP_ER_MEMORY, 0);

+ return NULL;

+ }

+

+ if ((ctx->in = buffer_new_read(data, len, freep)) == NULL) {

+ zip_error_set(error, ZIP_ER_MEMORY, 0);

+ free(ctx);

+ return NULL;

+ }

+

+ ctx->out = NULL;

+ ctx->mtime = time(NULL);

+ zip_error_init(&ctx->error);

+

+ if ((zs=zip_source_function_create(read_data, ctx, error)) == NULL) {

+ buffer_free(ctx->in);

+ free(ctx);

+ return NULL;

+ }

+

+ return zs;

+}

+

+

+static zip_int64_t

+read_data(void *state, void *data, zip_uint64_t len, zip_source_cmd_t cmd)

+{

+ struct read_data *ctx = (struct read_data *)state;

+

+ switch (cmd) {

+ case ZIP_SOURCE_BEGIN_WRITE:

+ if ((ctx->out = buffer_new_write(WRITE_FRAGMENT_SIZE)) == NULL) {

+ zip_error_set(&ctx->error, ZIP_ER_MEMORY, 0);

+ return -1;

+ }

+ return 0;

+

+ case ZIP_SOURCE_CLOSE:

+ return 0;

+

+ case ZIP_SOURCE_COMMIT_WRITE:

+ buffer_free(ctx->in);

+ ctx->in = ctx->out;

+ ctx->out = NULL;

+ return 0;

+

+ case ZIP_SOURCE_ERROR:

+ return zip_error_to_data(&ctx->error, data, len);

+

+ case ZIP_SOURCE_FREE:

+ buffer_free(ctx->in);

+ buffer_free(ctx->out);

+ free(ctx);

+ return 0;

+

+ case ZIP_SOURCE_OPEN:

+ ctx->in->offset = 0;

+ return 0;

+

+ case ZIP_SOURCE_READ:

+ if (len > ZIP_INT64_MAX) {

+ zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);

+ return -1;

+ }

+ return buffer_read(ctx->in, data, len);

+

+ case ZIP_SOURCE_REMOVE:

+ {

+ buffer_t *empty = buffer_new_read(NULL, 0, 0);

+ if (empty == 0) {

+ zip_error_set(&ctx->error, ZIP_ER_MEMORY, 0);

+ return -1;

+ }

+

+ buffer_free(ctx->in);

+ ctx->in = empty;

+ return 0;

+ }

+

+ case ZIP_SOURCE_ROLLBACK_WRITE:

+ buffer_free(ctx->out);

+ ctx->out = NULL;

+ return 0;

+

+ case ZIP_SOURCE_SEEK:

+ return buffer_seek(ctx->in, data, len, &ctx->error);

+

+ case ZIP_SOURCE_SEEK_WRITE:

+ return buffer_seek(ctx->out, data, len, &ctx->error);

+

+ case ZIP_SOURCE_STAT:

+ {

+ zip_stat_t *st;

+

+ if (len < sizeof(*st)) {

+ zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);

+ return -1;

+ }

+

+ st = (zip_stat_t *)data;

+

+ zip_stat_init(st);

+ st->mtime = ctx->mtime;

+ st->size = ctx->in->size;

+ st->comp_size = st->size;

+ st->comp_method = ZIP_CM_STORE;

+ st->encryption_method = ZIP_EM_NONE;

+ st->valid = ZIP_STAT_MTIME|ZIP_STAT_SIZE|ZIP_STAT_COMP_SIZE|ZIP_STAT_COMP_METHOD|ZIP_STAT_ENCRYPTION_METHOD;

+

+ return sizeof(*st);

+ }

+

+ case ZIP_SOURCE_SUPPORTS:

+ return zip_source_make_command_bitmap(ZIP_SOURCE_OPEN, ZIP_SOURCE_READ, ZIP_SOURCE_CLOSE, ZIP_SOURCE_STAT, ZIP_SOURCE_ERROR, ZIP_SOURCE_FREE, ZIP_SOURCE_SEEK, ZIP_SOURCE_TELL, ZIP_SOURCE_BEGIN_WRITE, ZIP_SOURCE_COMMIT_WRITE, ZIP_SOURCE_REMOVE, ZIP_SOURCE_ROLLBACK_WRITE, ZIP_SOURCE_SEEK_WRITE, ZIP_SOURCE_TELL_WRITE, ZIP_SOURCE_WRITE, -1);

+

+ case ZIP_SOURCE_TELL:

+ if (ctx->in->offset > ZIP_INT64_MAX) {

+ zip_error_set(&ctx->error, ZIP_ER_TELL, EOVERFLOW);

+ return -1;

+ }

+ return (zip_int64_t)ctx->in->offset;

+

+

+ case ZIP_SOURCE_TELL_WRITE:

+ if (ctx->out->offset > ZIP_INT64_MAX) {

+ zip_error_set(&ctx->error, ZIP_ER_TELL, EOVERFLOW);

+ return -1;

+ }

+ return (zip_int64_t)ctx->out->offset;

+

+ case ZIP_SOURCE_WRITE:

+ if (len > ZIP_INT64_MAX) {

+ zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);

+ return -1;

+ }

+ return buffer_write(ctx->out, data, len, &ctx->error);

+

+ default:

+ zip_error_set(&ctx->error, ZIP_ER_OPNOTSUPP, 0);

+ return -1;

+ }

+}

+

+

+static void

+buffer_free(buffer_t *buffer)

+{

+ if (buffer == NULL) {

+ return;

+ }

+

+ if (buffer->free_data) {

+ zip_uint64_t i;

+

+ for (i=0; i < buffer->nfragments; i++) {

+ free(buffer->fragments[i]);

+ }

+ }

+ free(buffer->fragments);

+ free(buffer);

+}

+

+

+static buffer_t *

+buffer_new(zip_uint64_t fragment_size)

+{

+ buffer_t *buffer;

+

+ if ((buffer = malloc(sizeof(*buffer))) == NULL) {

+ return NULL;

+ }

+

+ buffer->fragment_size = fragment_size;

+ buffer->offset = 0;

+ buffer->free_data = 0;

+ buffer->nfragments = 0;

+ buffer->fragments_capacity = 0;

+ buffer->fragments = NULL;

+ buffer->size = 0;

+

+ return buffer;

+}

+

+

+static buffer_t *

+buffer_new_read(const void *data, zip_uint64_t length, int free_data)

+{

+ buffer_t *buffer;

+

+ if ((buffer = buffer_new(length)) == NULL) {

+ return NULL;

+ }

+

+ buffer->size = length;

+

+ if (length > 0) {

+ if ((buffer->fragments = malloc(sizeof(*(buffer->fragments)))) == NULL) {

+ buffer_free(buffer);

+ return NULL;

+ }

+ buffer->fragments_capacity = 1;

+

+ buffer->nfragments = 1;

+ buffer->fragments[0] = (zip_uint8_t *)data;

+ buffer->free_data = free_data;

+ }

+

+ return buffer;

+}

+

+

+static buffer_t *

+buffer_new_write(zip_uint64_t fragment_size)

+{

+ buffer_t *buffer;

+

+ if ((buffer = buffer_new(fragment_size)) == NULL) {

+ return NULL;

+ }

+

+ if ((buffer->fragments = malloc(sizeof(*(buffer->fragments)))) == NULL) {

+ buffer_free(buffer);

+ return NULL;

+ }

+ buffer->fragments_capacity = 1;

+ buffer->nfragments = 0;

+ buffer->free_data = 1;

+

+ return buffer;

+}

+

+

+static zip_int64_t

+buffer_read(buffer_t *buffer, zip_uint8_t *data, zip_uint64_t length)

+{

+ zip_uint64_t n, i, fragment_offset;

+

+ length = ZIP_MIN(length, buffer->size - buffer->offset);

+

+ if (length == 0) {

+ return 0;

+ }

+ if (length > ZIP_INT64_MAX) {

+ return -1;

+ }

+

+ i = buffer->offset / buffer->fragment_size;

+ fragment_offset = buffer->offset % buffer->fragment_size;

+ n = 0;

+ while (n < length) {

+ zip_uint64_t left = ZIP_MIN(length - n, buffer->fragment_size - fragment_offset);

+

+ memcpy(data + n, buffer->fragments[i] + fragment_offset, left);

+

+ n += left;

+ i++;

+ fragment_offset = 0;

+ }

+

+ buffer->offset += n;

+ return (zip_int64_t)n;

+}

+

+

+static int

+buffer_seek(buffer_t *buffer, void *data, zip_uint64_t len, zip_error_t *error)

+{

+ zip_int64_t new_offset = zip_source_seek_compute_offset(buffer->offset, buffer->size, data, len, error);

+

+ if (new_offset < 0) {

+ return -1;

+ }

+

+ buffer->offset = (zip_uint64_t)new_offset;

+ return 0;

+}

+

+

+static zip_int64_t

+buffer_write(buffer_t *buffer, const zip_uint8_t *data, zip_uint64_t length, zip_error_t *error)

+{

+ zip_uint64_t n, i, fragment_offset;

+ zip_uint8_t **fragments;

+

+ if (buffer->offset + length + buffer->fragment_size - 1 < length) {

+ zip_error_set(error, ZIP_ER_INVAL, 0);

+ return -1;

+ }

+

+ /* grow buffer if needed */

+ if (buffer->offset + length > buffer->nfragments * buffer->fragment_size) {

+ zip_uint64_t needed_fragments = (buffer->offset + length + buffer->fragment_size - 1) / buffer->fragment_size;

+

+ if (needed_fragments > buffer->fragments_capacity) {

+ zip_uint64_t new_capacity = buffer->fragments_capacity;

+

+ while (new_capacity < needed_fragments) {

+ new_capacity *= 2;

+ }

+

+ fragments = realloc(buffer->fragments, new_capacity * sizeof(*fragments));

+

+ if (fragments == NULL) {

+ zip_error_set(error, ZIP_ER_MEMORY, 0);

+ return -1;

+ }

+

+ buffer->fragments = fragments;

+ buffer->fragments_capacity = new_capacity;

+ }

+

+ while (buffer->nfragments < needed_fragments) {

+ if ((buffer->fragments[buffer->nfragments] = malloc(buffer->fragment_size)) == NULL) {

+ zip_error_set(error, ZIP_ER_MEMORY, 0);

+ return -1;

+ }

+ buffer->nfragments++;

+ }

+ }

+

+ i = buffer->offset / buffer->fragment_size;

+ fragment_offset = buffer->offset % buffer->fragment_size;

+ n = 0;

+ while (n < length) {

+ zip_uint64_t left = ZIP_MIN(length - n, buffer->fragment_size - fragment_offset);

+

+ memcpy(buffer->fragments[i] + fragment_offset, data + n, left);

+

+ n += left;

+ i++;

+ fragment_offset = 0;

+ }

+

+ buffer->offset += n;

+ if (buffer->offset > buffer->size) {

+ buffer->size = buffer->offset;

+ }

+

+ return (zip_int64_t)n;

+}