php-src/main/memory_streams.c
2002-11-18 12:40:12 +00:00

473 lines
10 KiB
C

/*
+----------------------------------------------------------------------+
| PHP Version 4 |
+----------------------------------------------------------------------+
| Copyright (c) 1997-2002 The PHP Group |
+----------------------------------------------------------------------+
| This source file is subject to version 2.02 of the PHP license, |
| that is bundled with this package in the file LICENSE, and is |
| available at through the world-wide-web at |
| http://www.php.net/license/2_02.txt. |
| If you did not receive a copy of the PHP license and are unable to |
| obtain it through the world-wide-web, please send a note to |
| license@php.net so we can mail you a copy immediately. |
+----------------------------------------------------------------------+
| Author: |
| Marcus Boerger <helly@php.net> |
+----------------------------------------------------------------------+
*/
#define _GNU_SOURCE
#include "php.h"
/* Memory streams use a dynamic memory buffer to emulate a stream.
* You can use php_stream_memory_open to create a readonly stream
* from an existing memory buffer.
*/
/* Temp streams are streams that uses memory streams as long their
* size is less than a given memory amount. When a write operation
* exceeds that limit the content is written to a temporary file.
*/
/* {{{ ------- MEMORY stream implementation -------*/
typedef struct {
char *data;
size_t fpos;
size_t fsize;
size_t smax;
int mode;
} php_stream_memory_data;
/* {{{ */
static size_t php_stream_memory_write(php_stream *stream, const char *buf, size_t count TSRMLS_DC)
{
php_stream_memory_data *ms;
assert(stream != NULL);
ms = stream->abstract;
assert(ms != NULL);
if (ms->mode & TEMP_STREAM_READONLY) {
return 0;
}
if (ms->fpos + count > ms->fsize) {
char *tmp;
if (!ms->data) {
tmp = emalloc(ms->fpos + count);
} else {
tmp = erealloc(ms->data, ms->fpos + count);
}
if (!tmp) {
count = ms->fsize - ms->fpos + 1;
} else {
ms->data = tmp;
ms->fsize = ms->fpos + count;
}
}
if (!ms->data)
count = 0;
if (count) {
assert(buf!= NULL);
memcpy(ms->data+ms->fpos, (char*)buf, count);
ms->fpos += count;
}
return count;
}
/* }}} */
/* {{{ */
static size_t php_stream_memory_read(php_stream *stream, char *buf, size_t count TSRMLS_DC)
{
php_stream_memory_data *ms;
assert(stream != NULL);
ms = stream->abstract;
assert(ms != NULL);
if (ms->fpos + count > ms->fsize) {
count = ms->fsize - ms->fpos;
}
if (count) {
assert(ms->data!= NULL);
assert(buf!= NULL);
memcpy(buf, ms->data+ms->fpos, count);
ms->fpos += count;
} else {
stream->eof = 1;
}
return count;
}
/* }}} */
/* {{{ */
static int php_stream_memory_close(php_stream *stream, int close_handle TSRMLS_DC)
{
php_stream_memory_data *ms;
assert(stream != NULL);
ms = stream->abstract;
assert(ms != NULL);
if (ms->data && close_handle && ms->mode != TEMP_STREAM_READONLY) {
efree(ms->data);
}
efree(ms);
return 0;
}
/* }}} */
/* {{{ */
static int php_stream_memory_flush(php_stream *stream TSRMLS_DC)
{
/* nothing to do here */
return 0;
}
/* }}} */
/* {{{ */
static int php_stream_memory_seek(php_stream *stream, off_t offset, int whence, off_t *newoffs TSRMLS_DC)
{
php_stream_memory_data *ms;
assert(stream != NULL);
ms = stream->abstract;
assert(ms != NULL);
switch(whence) {
case SEEK_CUR:
if (offset < 0) {
if (ms->fpos < (size_t)(-offset)) {
ms->fpos = 0;
/*return EINVAL;*/
} else {
ms->fpos = ms->fpos + offset;
}
} else {
if (ms->fpos < (size_t)(offset)) {
ms->fpos = ms->fsize;
/*return EINVAL;*/
} else {
ms->fpos = ms->fpos + offset;
}
}
*newoffs = ms->fpos;
return 0;
case SEEK_SET:
if (ms->fsize < (size_t)(offset)) {
ms->fpos = ms->fsize;
/*return EINVAL;*/
} else {
ms->fpos = offset;
}
*newoffs = ms->fpos;
return 0;
case SEEK_END:
if (offset > 0) {
ms->fpos = ms->fsize;
/*return EINVAL;*/
} else if (ms->fpos < (size_t)(-offset)) {
ms->fpos = 0;
/*return EINVAL;*/
} else {
ms->fpos = ms->fsize + offset;
}
*newoffs = ms->fpos;
return 0;
default:
return 0;
/*return EINVAL;*/
}
}
/* }}} */
/* {{{ */
static int php_stream_memory_cast(php_stream *stream, int castas, void **ret TSRMLS_DC)
{
return FAILURE;
}
/* }}} */
php_stream_ops php_stream_memory_ops = {
php_stream_memory_write, php_stream_memory_read,
php_stream_memory_close, php_stream_memory_flush,
"MEMORY",
php_stream_memory_seek,
php_stream_memory_cast,
NULL, /* stat */
NULL /* set_option */
};
/* {{{ */
PHPAPI php_stream *_php_stream_memory_create(int mode STREAMS_DC TSRMLS_DC)
{
php_stream_memory_data *self;
php_stream *stream;
self = emalloc(sizeof(*self));
assert(self != NULL);
self->data = NULL;
self->fpos = 0;
self->fsize = 0;
self->smax = -1;
self->mode = mode;
stream = php_stream_alloc(&php_stream_memory_ops, self, 0, "r+b");
stream->flags |= PHP_STREAM_FLAG_NO_BUFFER;
return stream;
}
/* }}} */
/* {{{ */
PHPAPI php_stream *_php_stream_memory_open(int mode, char *buf, size_t length STREAMS_DC TSRMLS_DC)
{
php_stream *stream;
php_stream_memory_data *ms;
if ((stream = php_stream_memory_create_rel(mode)) != NULL) {
ms = stream->abstract;
if (mode == TEMP_STREAM_READONLY) {
/* use the buffer directly */
ms->data = buf;
ms->fsize = length;
} else {
if (length) {
assert(buf != NULL);
php_stream_write(stream, buf, length);
}
}
}
return stream;
}
/* }}} */
/* {{{ */
PHPAPI char *_php_stream_memory_get_buffer(php_stream *stream, size_t *length STREAMS_DC TSRMLS_DC)
{
php_stream_memory_data *ms;
assert(stream != NULL);
ms = stream->abstract;
assert(ms != NULL);
assert(length != 0);
*length = ms->fsize;
return ms->data;
}
/* }}} */
/* }}} */
/* {{{ ------- TEMP stream implementation -------*/
typedef struct {
php_stream *innerstream;
size_t smax;
int mode;
} php_stream_temp_data;
/* {{{ */
static size_t php_stream_temp_write(php_stream *stream, const char *buf, size_t count TSRMLS_DC)
{
php_stream_temp_data *ts;
assert(stream != NULL);
ts = stream->abstract;
assert(ts != NULL);
if (php_stream_is(ts->innerstream, PHP_STREAM_IS_MEMORY)) {
size_t memsize;
char *membuf = php_stream_memory_get_buffer(ts->innerstream, &memsize);
if (memsize + count >= ts->smax) {
php_stream *file = php_stream_fopen_tmpfile();
php_stream_write(file, membuf, memsize);
php_stream_close(ts->innerstream);
ts->innerstream = file;
}
}
return php_stream_write(ts->innerstream, buf, count);
}
/* }}} */
/* {{{ */
static size_t php_stream_temp_read(php_stream *stream, char *buf, size_t count TSRMLS_DC)
{
php_stream_temp_data *ts;
assert(stream != NULL);
ts = stream->abstract;
assert(ts != NULL);
return php_stream_read(ts->innerstream, buf, count);
}
/* }}} */
/* {{{ */
static int php_stream_temp_close(php_stream *stream, int close_handle TSRMLS_DC)
{
php_stream_temp_data *ts;
int ret;
assert(stream != NULL);
ts = stream->abstract;
assert(ts != NULL);
ret = php_stream_free(ts->innerstream, PHP_STREAM_FREE_CLOSE | (close_handle ? 0 : PHP_STREAM_FREE_PRESERVE_HANDLE));
efree(ts);
return ret;
}
/* }}} */
/* {{{ */
static int php_stream_temp_flush(php_stream *stream TSRMLS_DC)
{
php_stream_temp_data *ts;
assert(stream != NULL);
ts = stream->abstract;
assert(ts != NULL);
return php_stream_flush(ts->innerstream);
}
/* }}} */
/* {{{ */
static int php_stream_temp_seek(php_stream *stream, off_t offset, int whence, off_t *newoffs TSRMLS_DC)
{
php_stream_temp_data *ts;
int ret;
assert(stream != NULL);
ts = stream->abstract;
assert(ts != NULL);
ret = php_stream_seek(ts->innerstream, offset, whence);
*newoffs = php_stream_tell(ts->innerstream);
return ret;
}
/* }}} */
/* {{{ */
static int php_stream_temp_cast(php_stream *stream, int castas, void **ret TSRMLS_DC)
{
php_stream_temp_data *ts;
php_stream *file;
size_t memsize;
char *membuf;
off_t pos;
assert(stream != NULL);
ts = stream->abstract;
assert(ts != NULL);
if (php_stream_is(ts->innerstream, PHP_STREAM_IS_STDIO)) {
return php_stream_cast(ts->innerstream, castas, ret, 0);
}
/* we are still using a memory based backing. If they are if we can be
* a FILE*, say yes because we can perform the conversion.
* If they actually want to perform the conversion, we need to switch
* the memory stream to a tmpfile stream */
if (ret == NULL && castas == PHP_STREAM_AS_STDIO) {
return SUCCESS;
}
/* say "no" to other stream forms */
if (ret == NULL) {
return FAILURE;
}
/* perform the conversion and then pass the request on to the innerstream */
membuf = php_stream_memory_get_buffer(ts->innerstream, &memsize);
file = php_stream_fopen_tmpfile();
php_stream_write(file, membuf, memsize);
pos = php_stream_tell(ts->innerstream);
php_stream_close(ts->innerstream);
ts->innerstream = file;
php_stream_seek(ts->innerstream, pos, SEEK_SET);
return php_stream_cast(ts->innerstream, castas, ret, 1);
}
/* }}} */
php_stream_ops php_stream_temp_ops = {
php_stream_temp_write, php_stream_temp_read,
php_stream_temp_close, php_stream_temp_flush,
"TEMP",
php_stream_temp_seek,
php_stream_temp_cast,
NULL, /* stat */
NULL /* set_option */
};
/* {{{ */
PHPAPI php_stream *_php_stream_temp_create(int mode, size_t max_memory_usage STREAMS_DC TSRMLS_DC)
{
php_stream_temp_data *self;
php_stream *stream;
self = ecalloc(1, sizeof(*self));
assert(self != NULL);
self->smax = max_memory_usage;
self->mode = mode;
stream = php_stream_alloc(&php_stream_temp_ops, self, 0, "r+b");
stream->flags |= PHP_STREAM_FLAG_NO_BUFFER;
self->innerstream = php_stream_memory_create(mode);
return stream;
}
/* }}} */
/* {{{ */
PHPAPI php_stream *_php_stream_temp_open(int mode, size_t max_memory_usage, char *buf, size_t length STREAMS_DC TSRMLS_DC)
{
php_stream *stream;
php_stream_temp_data *ms;
if ((stream = php_stream_temp_create_rel(mode & ~TEMP_STREAM_READONLY, max_memory_usage)) != NULL) {
if (length) {
assert(buf != NULL);
php_stream_temp_write(stream, buf, length TSRMLS_CC);
}
ms = stream->abstract;
assert(ms != NULL);
ms->mode = mode;
}
return stream;
}
/* }}} */
/*
* Local variables:
* tab-width: 4
* c-basic-offset: 4
* End:
* vim600: noet sw=4 ts=4 fdm=marker
* vim<600: noet sw=4 ts=4
*/