zip_source_buffer.c [plain text]
#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;
zip_uint8_t **fragments;
zip_uint64_t nfragments;
zip_uint64_t fragments_capacity;
zip_uint64_t size;
zip_uint64_t 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;
}
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;
}