/* * This file is part of LibParserUtils. * Licensed under the MIT License, *                http://www.opensource.org/licenses/mit-license.php * Copyright 2008 John-Mark Bell <jmb@netsurf-browser.org> */ #include <string.h> #include <parserutils/utils/buffer.h> #define DEFAULT_SIZE (4096) /** * Create a memory buffer * * \param alloc   Memory (de)allocation function * \param pw      Pointer to client-specific private data * \param buffer  Pointer to location to receive memory buffer * \return PARSERUTILS_OK on success, *         PARSERUTILS_BADPARM on bad parameters, *         PARSERUTILS_NOMEM on memory exhausion */parserutils_error parserutils_buffer_create(parserutils_alloc alloc, void *pw,		parserutils_buffer **buffer){	parserutils_buffer *b; 	if (alloc == NULL || buffer == NULL)		return PARSERUTILS_BADPARM; 	b = alloc(NULL, sizeof(parserutils_buffer), pw);	if (b == NULL)		return PARSERUTILS_NOMEM; 	b->data = alloc(NULL, DEFAULT_SIZE, pw);	if (b->data == NULL) {		alloc(b, 0, pw);		return PARSERUTILS_NOMEM;	} 	b->length = 0;	b->allocated = DEFAULT_SIZE; 	b->alloc = alloc;	b->pw = pw; 	*buffer = b; 	return PARSERUTILS_OK;} /** * Destroy a memory buffer * * \param buffer  The buffer to destroy * \return PARSERUTILS_OK on success, appropriate error otherwise */parserutils_error parserutils_buffer_destroy(parserutils_buffer *buffer){	if (buffer == NULL)		return PARSERUTILS_BADPARM; 	buffer->alloc(buffer->data, 0, buffer->pw);	buffer->alloc(buffer, 0, buffer->pw); 	return PARSERUTILS_OK;} /** * Append data to a memory buffer * * \param buffer  The buffer to append to * \param data    The data to append * \param len     The length, in bytes, of the data to append * \return PARSERUTILS_OK on success, appropriate error otherwise. */parserutils_error parserutils_buffer_append(parserutils_buffer *buffer, 		const uint8_t *data, size_t len){	while (len >= buffer->allocated - buffer->length) {		parserutils_error error = parserutils_buffer_grow(buffer);		if (error != PARSERUTILS_OK)			return error;	} 	memcpy(buffer->data + buffer->length, data, len); 	buffer->length += len; 	return PARSERUTILS_OK;} /** * Insert data into a memory buffer * * \param buffer  The buffer to insert into * \param offset  The offset into the buffer to insert at * \param data    The data to insert * \param len     The length, in bytes, of the data to insert * \return PARSERUTILS_OK on success, appropriate error otherwise */parserutils_error parserutils_buffer_insert(parserutils_buffer *buffer, 		size_t offset, const uint8_t *data, size_t len){	if (offset > buffer->length)		return PARSERUTILS_BADPARM; 	if (offset == buffer->length)		return parserutils_buffer_append(buffer, data, len); 	while (len >= buffer->allocated - buffer->length) {		parserutils_error error = parserutils_buffer_grow(buffer);		if (error != PARSERUTILS_OK)			return error;	} 	memmove(buffer->data + buffer->length + len, 			buffer->data + offset, buffer->length - offset); 	memcpy(buffer->data + offset, data, len); 	buffer->length += len; 	return PARSERUTILS_OK;} /** * Discard a section of a memory buffer * * \param buffer  The buffer to discard data from * \param offset  The offset into the buffer of the start of the section * \param len     The number of bytes to discard * \return PARSERUTILS_OK on success, appropriate error otherwise. */parserutils_error parserutils_buffer_discard(parserutils_buffer *buffer, 		size_t offset, size_t len){	if (offset >= buffer->length || offset + len > buffer->length)		return PARSERUTILS_BADPARM; 	memmove(buffer->data + offset, buffer->data + offset + len, 			buffer->length - len); 	buffer->length -= len; 	return PARSERUTILS_OK;} /** * Extend the amount of space allocated for a memory buffer * * \param buffer  The buffer to extend * \return PARSERUTILS_OK on success, appropriate error otherwise. */parserutils_error parserutils_buffer_grow(parserutils_buffer *buffer){	uint8_t *temp = buffer->alloc(buffer->data, 			buffer->allocated * 2, buffer->pw);	if (temp == NULL)		return PARSERUTILS_NOMEM; 	buffer->data = temp;	buffer->allocated *= 2; 	return PARSERUTILS_OK;} parserutils_error parserutils_buffer_randomise(parserutils_buffer *buffer){#ifndef NDEBUG	uint8_t *temp;#endif 	if (buffer == NULL)		return PARSERUTILS_BADPARM; #ifndef NDEBUG	temp = buffer->alloc(NULL, buffer->allocated, buffer->pw);	if (temp == NULL)		return PARSERUTILS_NOMEM; 	memcpy(temp, buffer->data, buffer->length); 	memset(buffer->data, 0xff, buffer->length); 	/* Leak the buffer's current data, so we don't reuse it */	/* buffer->alloc(buffer->data, 0, buffer->pw); */ 	buffer->data = temp;#endif  	return PARSERUTILS_OK;}