diff options
Diffstat (limited to 'plugingui/png/pngrio.c')
| -rw-r--r-- | plugingui/png/pngrio.c | 176 |
1 files changed, 0 insertions, 176 deletions
diff --git a/plugingui/png/pngrio.c b/plugingui/png/pngrio.c deleted file mode 100644 index e45df21..0000000 --- a/plugingui/png/pngrio.c +++ /dev/null @@ -1,176 +0,0 @@ - -/* pngrio.c - functions for data input - * - * Last changed in libpng 1.5.0 [January 6, 2011] - * Copyright (c) 1998-2011 Glenn Randers-Pehrson - * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) - * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) - * - * This code is released under the libpng license. - * For conditions of distribution and use, see the disclaimer - * and license in png.h - * - * This file provides a location for all input. Users who need - * special handling are expected to write a function that has the same - * arguments as this and performs a similar function, but that possibly - * has a different input method. Note that you shouldn't change this - * function, but rather write a replacement function and then make - * libpng use it at run time with png_set_read_fn(...). - */ - -#include "pngpriv.h" - -#ifdef PNG_READ_SUPPORTED - -/* Read the data from whatever input you are using. The default routine - * reads from a file pointer. Note that this routine sometimes gets called - * with very small lengths, so you should implement some kind of simple - * buffering if you are using unbuffered reads. This should never be asked - * to read more then 64K on a 16 bit machine. - */ -void /* PRIVATE */ -png_read_data(png_structp png_ptr, png_bytep data, png_size_t length) -{ - png_debug1(4, "reading %d bytes", (int)length); - - if (png_ptr->read_data_fn != NULL) - (*(png_ptr->read_data_fn))(png_ptr, data, length); - - else - dg_png_error(png_ptr, "Call to NULL read function"); -} - -#ifdef PNG_STDIO_SUPPORTED -/* This is the function that does the actual reading of data. If you are - * not reading from a standard C stream, you should create a replacement - * read_data function and use it at run time with png_set_read_fn(), rather - * than changing the library. - */ -# ifndef USE_FAR_KEYWORD -void PNGCBAPI -png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length) -{ - png_size_t check; - - if (png_ptr == NULL) - return; - - /* fread() returns 0 on error, so it is OK to store this in a png_size_t - * instead of an int, which is what fread() actually returns. - */ - check = fread(data, 1, length, (png_FILE_p)png_ptr->io_ptr); - - if (check != length) - dg_png_error(png_ptr, "Read Error"); -} -# else -/* This is the model-independent version. Since the standard I/O library - can't handle far buffers in the medium and small models, we have to copy - the data. -*/ - -#define NEAR_BUF_SIZE 1024 -#define MIN(a,b) (a <= b ? a : b) - -static void PNGCBAPI -png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length) -{ - png_size_t check; - png_byte *n_data; - png_FILE_p io_ptr; - - if (png_ptr == NULL) - return; - - /* Check if data really is near. If so, use usual code. */ - n_data = (png_byte *)CVT_PTR_NOCHECK(data); - io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr); - - if ((png_bytep)n_data == data) - { - check = fread(n_data, 1, length, io_ptr); - } - - else - { - png_byte buf[NEAR_BUF_SIZE]; - png_size_t read, remaining, err; - check = 0; - remaining = length; - - do - { - read = MIN(NEAR_BUF_SIZE, remaining); - err = fread(buf, 1, read, io_ptr); - png_memcpy(data, buf, read); /* copy far buffer to near buffer */ - - if (err != read) - break; - - else - check += err; - - data += read; - remaining -= read; - } - while (remaining != 0); - } - - if ((png_uint_32)check != (png_uint_32)length) - dg_png_error(png_ptr, "read Error"); -} -# endif -#endif - -/* This function allows the application to supply a new input function - * for libpng if standard C streams aren't being used. - * - * This function takes as its arguments: - * - * png_ptr - pointer to a png input data structure - * - * io_ptr - pointer to user supplied structure containing info about - * the input functions. May be NULL. - * - * read_data_fn - pointer to a new input function that takes as its - * arguments a pointer to a png_struct, a pointer to - * a location where input data can be stored, and a 32-bit - * unsigned int that is the number of bytes to be read. - * To exit and output any fatal error messages the new write - * function should call png_error(png_ptr, "Error msg"). - * May be NULL, in which case libpng's default function will - * be used. - */ -void PNGAPI -dg_png_set_read_fn(png_structp png_ptr, png_voidp io_ptr, - png_rw_ptr read_data_fn) -{ - if (png_ptr == NULL) - return; - - png_ptr->io_ptr = io_ptr; - -#ifdef PNG_STDIO_SUPPORTED - if (read_data_fn != NULL) - png_ptr->read_data_fn = read_data_fn; - - else - png_ptr->read_data_fn = png_default_read_data; -#else - png_ptr->read_data_fn = read_data_fn; -#endif - - /* It is an error to write to a read device */ - if (png_ptr->write_data_fn != NULL) - { - png_ptr->write_data_fn = NULL; - png_warning(png_ptr, - "Can't set both read_data_fn and write_data_fn in the" - " same structure"); - } - -#ifdef PNG_WRITE_FLUSH_SUPPORTED - png_ptr->output_flush_fn = NULL; -#endif -} -#endif /* PNG_READ_SUPPORTED */ |