The png decoder for Dillo. More...

#include <config.h>
#include <stdlib.h>
#include <png.h>
#include "msg.h"
#include "image.hh"
#include "cache.h"
#include "dicache.h"

Include dependency graph for png.c:

Go to the source code of this file.

Macros
#define	DATASIZE (png->ipbufsize - png->ipbufstart)

Enumerations
enum	prog_state { IS_finished , IS_init , IS_nextdata }

Functions
static void	Png_error_handling (png_structp png_ptr, png_const_charp msg)

static void	Png_warning_handler (png_structp png_ptr, png_const_charp msg)

static void	Png_datainfo_callback (png_structp png_ptr, png_infop info_ptr)

static void	Png_datarow_callback (png_structp png_ptr, png_bytep new_row, png_uint_32 row_num, int pass)

static void	Png_dataend_callback (png_structp png_ptr, png_infop info_ptr)

static void	Png_free (DilloPng *png)
	Free up the resources for this image.

static void	Png_close (DilloPng png, CacheClient_t Client)
	Finish the decoding process (and free the memory)

static void	Png_write (DilloPng png, void Buf, uint_t BufSize)
	Receive and process new chunks of PNG image data.

void	a_Png_callback (int Op, void *data)
	PNG callback.

void *	a_Png_new (DilloImage Image, DilloUrl url, int version)
	Create the image state data that must be kept between calls.

Detailed Description

The png decoder for Dillo.

It is responsible for decoding PNG data and transferring it to the dicache.

"PNG: The Definitive Guide" by Greg Roelofs, O'Reilly ISBN 1-56592-542-4

Definition in file png.c.

Macro Definition Documentation

◆ DATASIZE

#define DATASIZE (png->ipbufsize - png->ipbufstart)

Definition at line 100 of file png.c.

Enumeration Type Documentation

◆ prog_state

enum prog_state

Enumerator
IS_finished
IS_init
IS_nextdata

Definition at line 32 of file png.c.

Function Documentation

◆ a_Png_callback()

void a_Png_callback	(	int	Op,
		void *	data
	)

PNG callback.

Op: Operation to perform.
- If (Op == 0) start or continue processing an image if image data exists.
- else terminate processing, cleanup any allocated memory, close down the decoding process.
Client->CbData : pointer to previously allocated DilloPng work area. This holds the current state of the image processing and is kept across calls to this routine.
Client->Buf : Pointer to data start.
Client->BufSize : the size of the data buffer.

You have to keep track of where you are in the image data and how much has been processed.

It's entirely possible that you will not see the end of the data. The user may terminate transfer via a Stop button or there may be a network failure. This means that you can't just wait for all the data to be presented before starting conversion and display.

Definition at line 426 of file png.c.

References CacheClient::Buf, CacheClient::BufSize, CA_Abort, CA_Close, CA_Send, CacheClient::CbData, Png_close(), Png_free(), and Png_write().