openjpeg/libopenjpeg/cio.c

821 lines
25 KiB
C

/*
* Copyright (c) 2002-2007, Communications and Remote Sensing Laboratory, Universite catholique de Louvain (UCL), Belgium
* Copyright (c) 2002-2007, Professor Benoit Macq
* Copyright (c) 2001-2003, David Janssens
* Copyright (c) 2002-2003, Yannick Verschueren
* Copyright (c) 2003-2007, Francois-Olivier Devaux and Antonin Descampe
* Copyright (c) 2005, Herve Drolon, FreeImage Team
* Copyright (c) 2008, Jerome Fimes, Communications & Systemes <jerome.fimes@c-s.fr>
* All rights reserved.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `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 COPYRIGHT OWNER OR CONTRIBUTORS 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 "cio.h"
#include "opj_includes.h"
#include "opj_malloc.h"
#include "event.h"
/* ----------------------------------------------------------------------- */
/**
* Write some bytes to the given data buffer, this function is used in Big Endian cpus.
* @param p_buffer pointer the data buffer to write data to.
* @param p_value the value to write
* @param p_nb_bytes the number of bytes to write
*/
void opj_write_bytes_BE (OPJ_BYTE * p_buffer, OPJ_UINT32 p_value, OPJ_UINT32 p_nb_bytes)
{
const OPJ_BYTE * l_data_ptr = ((const OPJ_BYTE *) &p_value) + p_nb_bytes;
assert(p_nb_bytes > 0 && p_nb_bytes <= sizeof(OPJ_UINT32));
memcpy(p_buffer,l_data_ptr,p_nb_bytes);
}
/**
* Write some bytes to the given data buffer, this function is used in Little Endian cpus.
* @param p_buffer pointer the data buffer to write data to.
* @param p_value the value to write
* @param p_nb_bytes the number of bytes to write
* @return the number of bytes written or -1 if an error occured
*/
void opj_write_bytes_LE (OPJ_BYTE * p_buffer, OPJ_UINT32 p_value, OPJ_UINT32 p_nb_bytes)
{
const OPJ_BYTE * l_data_ptr = ((const OPJ_BYTE *) &p_value) + p_nb_bytes - 1;
OPJ_UINT32 i;
assert(p_nb_bytes > 0 && p_nb_bytes <= sizeof(OPJ_UINT32));
for
(i=0;i<p_nb_bytes;++i)
{
*(p_buffer++) = *(l_data_ptr--);
}
}
/**
* Reads some bytes from the given data buffer, this function is used in Big Endian cpus.
* @param p_buffer pointer the data buffer to read data from.
* @param p_value pointer to the value that will store the data.
* @param p_nb_bytes the nb bytes to read.
* @return the number of bytes read or -1 if an error occured.
*/
void opj_read_bytes_BE(const OPJ_BYTE * p_buffer, OPJ_UINT32 * p_value, OPJ_UINT32 p_nb_bytes)
{
OPJ_BYTE * l_data_ptr = ((OPJ_BYTE *) p_value);
assert(p_nb_bytes > 0 && p_nb_bytes <= sizeof(OPJ_UINT32));
*p_value = 0;
memcpy(l_data_ptr+4-p_nb_bytes,p_buffer,p_nb_bytes);
}
/**
* Reads some bytes from the given data buffer, this function is used in Little Endian cpus.
* @param p_buffer pointer the data buffer to read data from.
* @param p_value pointer to the value that will store the data.
* @param p_nb_bytes the nb bytes to read.
* @return the number of bytes read or -1 if an error occured.
*/
void opj_read_bytes_LE(const OPJ_BYTE * p_buffer, OPJ_UINT32 * p_value, OPJ_UINT32 p_nb_bytes)
{
OPJ_BYTE * l_data_ptr = ((OPJ_BYTE *) p_value) + p_nb_bytes-1;
OPJ_UINT32 i;
assert(p_nb_bytes > 0 && p_nb_bytes <= sizeof(OPJ_UINT32));
*p_value = 0;
for
(i=0;i<p_nb_bytes;++i)
{
*(l_data_ptr--) = *(p_buffer++);
}
}
/**
* Write some bytes to the given data buffer, this function is used in Big Endian cpus.
* @param p_buffer pointer the data buffer to write data to.
* @param p_value the value to write
* @return the number of bytes written or -1 if an error occured
*/
void opj_write_double_BE(OPJ_BYTE * p_buffer, OPJ_FLOAT64 p_value)
{
const OPJ_BYTE * l_data_ptr = ((const OPJ_BYTE *) &p_value);
memcpy(p_buffer,l_data_ptr,sizeof(OPJ_FLOAT64));
}
/**
* Write some bytes to the given data buffer, this function is used in Little Endian cpus.
* @param p_buffer pointer the data buffer to write data to.
* @param p_value the value to write
*/
void opj_write_double_LE(OPJ_BYTE * p_buffer, OPJ_FLOAT64 p_value)
{
const OPJ_BYTE * l_data_ptr = ((const OPJ_BYTE *) &p_value) + sizeof(OPJ_FLOAT64) - 1;
OPJ_UINT32 i;
for
(i=0;i<sizeof(OPJ_FLOAT64);++i)
{
*(p_buffer++) = *(l_data_ptr--);
}
}
/**
* Reads some bytes from the given data buffer, this function is used in Big Endian cpus.
* @param p_buffer pointer the data buffer to read data from.
* @param p_value pointer to the value that will store the data.
*/
void opj_read_double_BE(const OPJ_BYTE * p_buffer, OPJ_FLOAT64 * p_value)
{
OPJ_BYTE * l_data_ptr = ((OPJ_BYTE *) p_value);
memcpy(l_data_ptr,p_buffer,sizeof(OPJ_FLOAT64));
}
/**
* Reads some bytes from the given data buffer, this function is used in Little Endian cpus.
* @param p_buffer pointer the data buffer to read data from.
* @param p_value pointer to the value that will store the data.
*/
void opj_read_double_LE(const OPJ_BYTE * p_buffer, OPJ_FLOAT64 * p_value)
{
OPJ_BYTE * l_data_ptr = ((OPJ_BYTE *) p_value) + sizeof(OPJ_FLOAT64)-1;
OPJ_UINT32 i;
for
(i=0;i<sizeof(OPJ_FLOAT64);++i)
{
*(l_data_ptr--) = *(p_buffer++);
}
}
/**
* Write some bytes to the given data buffer, this function is used in Big Endian cpus.
* @param p_buffer pointer the data buffer to write data to.
* @param p_value the value to write
* @return the number of bytes written or -1 if an error occured
*/
void opj_write_float_BE(OPJ_BYTE * p_buffer, OPJ_FLOAT32 p_value)
{
const OPJ_BYTE * l_data_ptr = ((const OPJ_BYTE *) &p_value);
memcpy(p_buffer,l_data_ptr,sizeof(OPJ_FLOAT32));
}
/**
* Write some bytes to the given data buffer, this function is used in Little Endian cpus.
* @param p_buffer pointer the data buffer to write data to.
* @param p_value the value to write
*/
void opj_write_float_LE(OPJ_BYTE * p_buffer, OPJ_FLOAT32 p_value)
{
const OPJ_BYTE * l_data_ptr = ((const OPJ_BYTE *) &p_value) + sizeof(OPJ_FLOAT32) - 1;
OPJ_UINT32 i;
for
(i=0;i<sizeof(OPJ_FLOAT32);++i)
{
*(p_buffer++) = *(l_data_ptr--);
}
}
/**
* Reads some bytes from the given data buffer, this function is used in Big Endian cpus.
* @param p_buffer pointer the data buffer to read data from.
* @param p_value pointer to the value that will store the data.
*/
void opj_read_float_BE(const OPJ_BYTE * p_buffer, OPJ_FLOAT32 * p_value)
{
OPJ_BYTE * l_data_ptr = ((OPJ_BYTE *) p_value);
memcpy(l_data_ptr,p_buffer,sizeof(OPJ_FLOAT32));
}
/**
* Reads some bytes from the given data buffer, this function is used in Little Endian cpus.
* @param p_buffer pointer the data buffer to read data from.
* @param p_value pointer to the value that will store the data.
*/
void opj_read_float_LE(const OPJ_BYTE * p_buffer, OPJ_FLOAT32 * p_value)
{
OPJ_BYTE * l_data_ptr = ((OPJ_BYTE *) p_value) + sizeof(OPJ_FLOAT32)-1;
OPJ_UINT32 i;
for
(i=0;i<sizeof(OPJ_FLOAT32);++i)
{
*(l_data_ptr--) = *(p_buffer++);
}
}
/**
* Creates an abstract stream. This function does nothing except allocating memory and initializing the abstract stream.
* @return a stream object.
*/
opj_stream_t* opj_stream_create(OPJ_UINT32 p_size,bool l_is_input)
{
opj_stream_private_t * l_stream = 00;
l_stream = (opj_stream_private_t*) opj_malloc(sizeof(opj_stream_private_t));
if
(! l_stream)
{
return 00;
}
memset(l_stream,0,sizeof(opj_stream_private_t));
l_stream->m_buffer_size = p_size;
l_stream->m_stored_data = (OPJ_BYTE *) opj_malloc(p_size);
if
(! l_stream->m_stored_data)
{
opj_free(l_stream);
return 00;
}
l_stream->m_current_data = l_stream->m_stored_data;
if
(l_is_input)
{
l_stream->m_status |= opj_stream_e_input;
l_stream->m_opj_skip = opj_stream_read_skip;
l_stream->m_opj_seek = opj_stream_read_seek;
}
else
{
l_stream->m_status |= opj_stream_e_output;
l_stream->m_opj_skip = opj_stream_write_skip;
l_stream->m_opj_seek = opj_stream_write_seek;
}
l_stream->m_read_fn = opj_stream_default_read;
l_stream->m_write_fn = opj_stream_default_write;
l_stream->m_skip_fn = opj_stream_default_skip;
l_stream->m_seek_fn = opj_stream_default_seek;
return (opj_stream_t *) l_stream;
}
/**
* Creates an abstract stream. This function does nothing except allocating memory and initializing the abstract stream.
* @return a stream object.
*/
opj_stream_t* opj_stream_default_create(bool l_is_input)
{
return opj_stream_create(J2K_STREAM_CHUNK_SIZE,l_is_input);
}
/**
* Destroys a stream created by opj_create_stream. This function does NOT close the abstract stream. If needed the user must
* close its own implementation of the stream.
*/
OPJ_API void OPJ_CALLCONV opj_stream_destroy(opj_stream_t* p_stream)
{
opj_stream_private_t* l_stream = (opj_stream_private_t*) p_stream;
if
(l_stream)
{
opj_free(l_stream->m_stored_data);
l_stream->m_stored_data = 00;
opj_free(l_stream);
}
}
/**
* Sets the given function to be used as a read function.
* @param p_stream the stream to modify
* @param p_function the function to use a read function.
*/
OPJ_API void OPJ_CALLCONV opj_stream_set_read_function(opj_stream_t* p_stream, opj_stream_read_fn p_function)
{
opj_stream_private_t* l_stream = (opj_stream_private_t*) p_stream;
if
((!l_stream) || (! (l_stream->m_status & opj_stream_e_input)))
{
return;
}
l_stream->m_read_fn = p_function;
}
OPJ_API void OPJ_CALLCONV opj_stream_set_seek_function(opj_stream_t* p_stream, opj_stream_seek_fn p_function)
{
opj_stream_private_t* l_stream = (opj_stream_private_t*) p_stream;
if
(!l_stream)
{
return;
}
l_stream->m_seek_fn = p_function;
}
/**
* Sets the given function to be used as a write function.
* @param p_stream the stream to modify
* @param p_function the function to use a write function.
*/
OPJ_API void OPJ_CALLCONV opj_stream_set_write_function(opj_stream_t* p_stream, opj_stream_write_fn p_function)
{
opj_stream_private_t* l_stream = (opj_stream_private_t*) p_stream;
if
((!l_stream )|| (! (l_stream->m_status & opj_stream_e_output)))
{
return;
}
l_stream->m_write_fn = p_function;
}
/**
* Sets the given function to be used as a skip function.
* @param p_stream the stream to modify
* @param p_function the function to use a skip function.
*/
OPJ_API void OPJ_CALLCONV opj_stream_set_skip_function(opj_stream_t* p_stream, opj_stream_skip_fn p_function)
{
opj_stream_private_t* l_stream = (opj_stream_private_t*) p_stream;
if
(! l_stream)
{
return;
}
l_stream->m_skip_fn = p_function;
}
/**
* Sets the given data to be used as a user data for the stream.
* @param p_stream the stream to modify
* @param p_data the data to set.
*/
OPJ_API void OPJ_CALLCONV opj_stream_set_user_data(opj_stream_t* p_stream, void * p_data)
{
opj_stream_private_t* l_stream = (opj_stream_private_t*) p_stream;
l_stream->m_user_data = p_data;
}
/**
* Reads some bytes from the stream.
* @param p_stream the stream to read data from.
* @param p_buffer pointer to the data buffer that will receive the data.
* @param p_size number of bytes to read.
* @param p_event_mgr the user event manager to be notified of special events.
* @return the number of bytes read, or -1 if an error occured or if the stream is at the end.
*/
OPJ_UINT32 opj_stream_read_data (opj_stream_private_t * p_stream,OPJ_BYTE * p_buffer, OPJ_UINT32 p_size, opj_event_mgr_t * p_event_mgr)
{
OPJ_UINT32 l_read_nb_bytes = 0;
if
(p_stream->m_bytes_in_buffer >= p_size)
{
memcpy(p_buffer,p_stream->m_current_data,p_size);
p_stream->m_current_data += p_size;
p_stream->m_bytes_in_buffer -= p_size;
l_read_nb_bytes += p_size;
p_stream->m_byte_offset += p_size;
return l_read_nb_bytes;
}
// we are now in the case when the remaining data if not sufficient
if
(p_stream->m_status & opj_stream_e_end)
{
l_read_nb_bytes += p_stream->m_bytes_in_buffer;
memcpy(p_buffer,p_stream->m_current_data,p_stream->m_bytes_in_buffer);
p_stream->m_current_data += p_stream->m_bytes_in_buffer;
p_stream->m_byte_offset += p_stream->m_bytes_in_buffer;
p_stream->m_bytes_in_buffer = 0;
return l_read_nb_bytes ? l_read_nb_bytes : -1;
}
// the flag is not set, we copy data and then do an actual read on the stream
if
(p_stream->m_bytes_in_buffer)
{
l_read_nb_bytes += p_stream->m_bytes_in_buffer;
memcpy(p_buffer,p_stream->m_current_data,p_stream->m_bytes_in_buffer);
p_stream->m_current_data = p_stream->m_stored_data;
p_buffer += p_stream->m_bytes_in_buffer;
p_size -= p_stream->m_bytes_in_buffer;
p_stream->m_byte_offset += p_stream->m_bytes_in_buffer;
p_stream->m_bytes_in_buffer = 0;
}
while
(true)
{
// we should read less than a chunk -> read a chunk
if
(p_size < p_stream->m_buffer_size)
{
// we should do an actual read on the media
p_stream->m_bytes_in_buffer = p_stream->m_read_fn(p_stream->m_stored_data,p_stream->m_buffer_size,p_stream->m_user_data);
if
(p_stream->m_bytes_in_buffer == -1)
{
// end of stream
opj_event_msg(p_event_mgr, EVT_INFO, "Stream reached its end !\n");
p_stream->m_bytes_in_buffer = 0;
p_stream->m_status |= opj_stream_e_end;
// end of stream
return l_read_nb_bytes ? l_read_nb_bytes : -1;
}
else if
(p_stream->m_bytes_in_buffer < p_size)
{
// not enough data
l_read_nb_bytes += p_stream->m_bytes_in_buffer;
memcpy(p_buffer,p_stream->m_current_data,p_stream->m_bytes_in_buffer);
p_stream->m_current_data = p_stream->m_stored_data;
p_buffer += p_stream->m_bytes_in_buffer;
p_size -= p_stream->m_bytes_in_buffer;
p_stream->m_byte_offset += p_stream->m_bytes_in_buffer;
p_stream->m_bytes_in_buffer = 0;
}
else
{
l_read_nb_bytes += p_size;
memcpy(p_buffer,p_stream->m_current_data,p_size);
p_stream->m_current_data += p_size;
p_stream->m_bytes_in_buffer -= p_size;
p_stream->m_byte_offset += p_size;
return l_read_nb_bytes;
}
}
else
{
// direct read on the dest buffer
p_stream->m_bytes_in_buffer = p_stream->m_read_fn(p_buffer,p_size,p_stream->m_user_data);
if
(p_stream->m_bytes_in_buffer == -1)
{
// end of stream
opj_event_msg(p_event_mgr, EVT_INFO, "Stream reached its end !\n");
p_stream->m_bytes_in_buffer = 0;
p_stream->m_status |= opj_stream_e_end;
// end of stream
return l_read_nb_bytes ? l_read_nb_bytes : -1;
}
else if
(p_stream->m_bytes_in_buffer < p_size)
{
// not enough data
l_read_nb_bytes += p_stream->m_bytes_in_buffer;
p_stream->m_current_data = p_stream->m_stored_data;
p_buffer += p_stream->m_bytes_in_buffer;
p_size -= p_stream->m_bytes_in_buffer;
p_stream->m_byte_offset += p_stream->m_bytes_in_buffer;
p_stream->m_bytes_in_buffer = 0;
}
else
{
// we have read the exact size
l_read_nb_bytes += p_stream->m_bytes_in_buffer;
p_stream->m_byte_offset += p_stream->m_bytes_in_buffer;
p_stream->m_current_data = p_stream->m_stored_data;
p_stream->m_bytes_in_buffer = 0;
return l_read_nb_bytes;
}
}
}
}
/**
* Writes some bytes from the stream.
* @param p_stream the stream to write data to.
* @param p_buffer pointer to the data buffer holds the data to be writtent.
* @param p_size number of bytes to write.
* @param p_event_mgr the user event manager to be notified of special events.
* @return the number of bytes writtent, or -1 if an error occured.
*/
OPJ_UINT32 opj_stream_write_data (opj_stream_private_t * p_stream,const OPJ_BYTE * p_buffer,OPJ_UINT32 p_size, opj_event_mgr_t * p_event_mgr)
{
OPJ_UINT32 l_remaining_bytes = 0;
OPJ_UINT32 l_write_nb_bytes = 0;
if
(p_stream->m_status & opj_stream_e_error)
{
return -1;
}
while
(true)
{
l_remaining_bytes = p_stream->m_buffer_size - p_stream->m_bytes_in_buffer;
// we have more memory than required
if
(l_remaining_bytes >= p_size)
{
memcpy(p_stream->m_current_data,p_buffer,p_size);
p_stream->m_current_data += p_size;
p_stream->m_bytes_in_buffer += p_size;
l_write_nb_bytes += p_size;
p_stream->m_byte_offset += p_size;
return l_write_nb_bytes;
}
// we copy data and then do an actual read on the stream
if
(l_remaining_bytes)
{
l_write_nb_bytes += l_remaining_bytes;
memcpy(p_stream->m_current_data,p_buffer,l_remaining_bytes);
p_stream->m_current_data = p_stream->m_stored_data;
p_buffer += l_remaining_bytes;
p_size -= l_remaining_bytes;
p_stream->m_bytes_in_buffer += l_remaining_bytes;
p_stream->m_byte_offset += l_remaining_bytes;
}
if
(! opj_stream_flush(p_stream, p_event_mgr))
{
return -1;
}
}
}
/**
* Writes the content of the stream buffer to the stream.
* @param p_stream the stream to write data to.
* @param p_event_mgr the user event manager to be notified of special events.
* @return the number of bytes written, or -1 if an error occured.
*/
bool opj_stream_flush (opj_stream_private_t * p_stream, opj_event_mgr_t * p_event_mgr)
{
// the number of bytes written on the media.
OPJ_UINT32 l_current_write_nb_bytes = 0;
p_stream->m_current_data = p_stream->m_stored_data;
while
(p_stream->m_bytes_in_buffer)
{
// we should do an actual write on the media
l_current_write_nb_bytes = p_stream->m_write_fn(p_stream->m_current_data,p_stream->m_bytes_in_buffer,p_stream->m_user_data);
if
(l_current_write_nb_bytes == -1)
{
p_stream->m_status |= opj_stream_e_error;
opj_event_msg(p_event_mgr, EVT_INFO, "Error on writting stream!\n");
return false;
}
p_stream->m_current_data += l_current_write_nb_bytes;
p_stream->m_bytes_in_buffer -= l_current_write_nb_bytes;
}
p_stream->m_current_data = p_stream->m_stored_data;
return true;
}
/**
* Skips a number of bytes from the stream.
* @param p_stream the stream to skip data from.
* @param p_size the number of bytes to skip.
* @param p_event_mgr the user event manager to be notified of special events.
* @return the number of bytes skipped, or -1 if an error occured.
*/
OPJ_SIZE_T opj_stream_read_skip (opj_stream_private_t * p_stream, OPJ_SIZE_T p_size, opj_event_mgr_t * p_event_mgr)
{
OPJ_SIZE_T l_skip_nb_bytes = 0;
OPJ_SIZE_T l_current_skip_nb_bytes = 0;
if
(p_stream->m_bytes_in_buffer >= p_size)
{
p_stream->m_current_data += p_size;
p_stream->m_bytes_in_buffer -= p_size;
l_skip_nb_bytes += p_size;
p_stream->m_byte_offset += l_skip_nb_bytes;
return l_skip_nb_bytes;
}
// we are now in the case when the remaining data if not sufficient
if
(p_stream->m_status & opj_stream_e_end)
{
l_skip_nb_bytes += p_stream->m_bytes_in_buffer;
p_stream->m_current_data += p_stream->m_bytes_in_buffer;
p_stream->m_bytes_in_buffer = 0;
p_stream->m_byte_offset += l_skip_nb_bytes;
return l_skip_nb_bytes ? l_skip_nb_bytes : (OPJ_SIZE_T) -1;
}
// the flag is not set, we copy data and then do an actual skip on the stream
if
(p_stream->m_bytes_in_buffer)
{
l_skip_nb_bytes += p_stream->m_bytes_in_buffer;
p_stream->m_current_data = p_stream->m_stored_data;
p_size -= p_stream->m_bytes_in_buffer;
p_stream->m_bytes_in_buffer = 0;
}
while
(p_size > 0)
{
// we should do an actual skip on the media
l_current_skip_nb_bytes = p_stream->m_skip_fn(p_size, p_stream->m_user_data);
if
(l_current_skip_nb_bytes == (OPJ_SIZE_T) -1)
{
opj_event_msg(p_event_mgr, EVT_INFO, "Stream reached its end !\n");
p_stream->m_status |= opj_stream_e_end;
p_stream->m_byte_offset += l_skip_nb_bytes;
// end if stream
return l_skip_nb_bytes ? l_skip_nb_bytes : (OPJ_SIZE_T) -1;
}
p_size -= l_current_skip_nb_bytes;
l_skip_nb_bytes += l_current_skip_nb_bytes;
}
p_stream->m_byte_offset += l_skip_nb_bytes;
return l_skip_nb_bytes;
}
/**
* Skips a number of bytes from the stream.
* @param p_stream the stream to skip data from.
* @param p_size the number of bytes to skip.
* @param p_event_mgr the user event manager to be notified of special events.
* @return the number of bytes skipped, or -1 if an error occured.
*/
OPJ_SIZE_T opj_stream_write_skip (opj_stream_private_t * p_stream, OPJ_SIZE_T p_size, opj_event_mgr_t * p_event_mgr)
{
bool l_is_written = 0;
OPJ_SIZE_T l_current_skip_nb_bytes = 0;
OPJ_SIZE_T l_skip_nb_bytes = 0;
if
(p_stream->m_status & opj_stream_e_error)
{
return (OPJ_SIZE_T) -1;
}
// we should flush data
l_is_written = opj_stream_flush (p_stream, p_event_mgr);
if
(! l_is_written)
{
p_stream->m_status |= opj_stream_e_error;
p_stream->m_bytes_in_buffer = 0;
p_stream->m_current_data = p_stream->m_current_data;
return (OPJ_SIZE_T) -1;
}
// then skip
while
(p_size > 0)
{
// we should do an actual skip on the media
l_current_skip_nb_bytes = p_stream->m_skip_fn(p_size, p_stream->m_user_data);
if
(l_current_skip_nb_bytes == (OPJ_SIZE_T)-1)
{
opj_event_msg(p_event_mgr, EVT_INFO, "Stream error!\n");
p_stream->m_status |= opj_stream_e_error;
p_stream->m_byte_offset += l_skip_nb_bytes;
// end if stream
return l_skip_nb_bytes ? l_skip_nb_bytes : (OPJ_SIZE_T)-1;
}
p_size -= l_current_skip_nb_bytes;
l_skip_nb_bytes += l_current_skip_nb_bytes;
}
p_stream->m_byte_offset += l_skip_nb_bytes;
return l_skip_nb_bytes;
}
/**
* Tells the byte offset on the stream (similar to ftell).
*
* @param p_stream the stream to get the information from.
*
* @return the current position o fthe stream.
*/
OPJ_SIZE_T opj_stream_tell (const opj_stream_private_t * p_stream)
{
return p_stream->m_byte_offset;
}
/**
* Skips a number of bytes from the stream.
* @param p_stream the stream to skip data from.
* @param p_size the number of bytes to skip.
* @param p_event_mgr the user event manager to be notified of special events.
* @return the number of bytes skipped, or -1 if an error occured.
*/
OPJ_SIZE_T opj_stream_skip (opj_stream_private_t * p_stream, OPJ_SIZE_T p_size, opj_event_mgr_t * p_event_mgr)
{
return p_stream->m_opj_skip(p_stream,p_size,p_event_mgr);
}
/**
* Skips a number of bytes from the stream.
* @param p_stream the stream to skip data from.
* @param p_size the number of bytes to skip.
* @param p_event_mgr the user event manager to be notified of special events.
* @return the number of bytes skipped, or -1 if an error occured.
*/
bool opj_stream_read_seek (opj_stream_private_t * p_stream, OPJ_SIZE_T p_size, opj_event_mgr_t * p_event_mgr)
{
p_stream->m_current_data = p_stream->m_stored_data;
p_stream->m_bytes_in_buffer = 0;
if
(! p_stream->m_seek_fn(p_size,p_stream->m_user_data))
{
p_stream->m_status |= opj_stream_e_end;
return false;
}
else
{
// reset stream status
p_stream->m_status &= (~opj_stream_e_end);
p_stream->m_byte_offset = p_size;
}
return true;
}
/**
* Skips a number of bytes from the stream.
* @param p_stream the stream to skip data from.
* @param p_size the number of bytes to skip.
* @param p_event_mgr the user event manager to be notified of special events.
* @return the number of bytes skipped, or -1 if an error occured.
*/
bool opj_stream_write_seek (opj_stream_private_t * p_stream, OPJ_SIZE_T p_size, opj_event_mgr_t * p_event_mgr)
{
if
(! opj_stream_flush(p_stream,p_event_mgr))
{
p_stream->m_status |= opj_stream_e_error;
return false;
}
p_stream->m_current_data = p_stream->m_stored_data;
p_stream->m_bytes_in_buffer = 0;
if
(! p_stream->m_seek_fn(p_size,p_stream->m_user_data))
{
p_stream->m_status |= opj_stream_e_error;
return false;
}
else
{
p_stream->m_byte_offset = p_size;
}
return true;
}
/**
* Seeks a number of bytes from the stream.
* @param p_stream the stream to skip data from.
* @param p_size the number of bytes to skip.
* @param p_event_mgr the user event manager to be notified of special events.
* @return true if the stream is seekable.
*/
bool opj_stream_seek (opj_stream_private_t * p_stream, OPJ_SIZE_T p_size, struct opj_event_mgr * p_event_mgr)
{
return p_stream->m_opj_seek(p_stream,p_size,p_event_mgr);
}
/**
* Tells if the given stream is seekable.
*/
bool opj_stream_has_seek (const opj_stream_private_t * p_stream)
{
return p_stream->m_seek_fn != opj_stream_default_seek;
}
OPJ_UINT32 opj_stream_default_read (void * p_buffer, OPJ_UINT32 p_nb_bytes, void * p_user_data)
{
return (OPJ_UINT32) -1;
}
OPJ_UINT32 opj_stream_default_write (void * p_buffer, OPJ_UINT32 p_nb_bytes, void * p_user_data)
{
return (OPJ_UINT32) -1;
}
OPJ_SIZE_T opj_stream_default_skip (OPJ_SIZE_T p_nb_bytes, void * p_user_data)
{
return (OPJ_SIZE_T) -1;
}
bool opj_stream_default_seek (OPJ_SIZE_T p_nb_bytes, void * p_user_data)
{
return false;
}