X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/0272a10d2e6d5323422c4c8600fe47ccac0df182..c017416682938c39547836051c0fad74db45e8a0:/src/png/pngrio.c diff --git a/src/png/pngrio.c b/src/png/pngrio.c index 7d2522f1f8..e9c381c5ba 100644 --- a/src/png/pngrio.c +++ b/src/png/pngrio.c @@ -1,12 +1,15 @@ /* pngrio.c - functions for data input * - * Last changed in libpng 1.2.13 November 13, 2006 - * For conditions of distribution and use, see copyright notice in png.h - * Copyright (c) 1998-2006 Glenn Randers-Pehrson + * 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 @@ -15,54 +18,53 @@ * libpng use it at run time with png_set_read_fn(...). */ -#define PNG_INTERNAL -#include "png.h" +#include "pngpriv.h" -#if defined(PNG_READ_SUPPORTED) +#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. */ + * 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\n", (int)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 png_error(png_ptr, "Call to NULL read function"); } -#if !defined(PNG_NO_STDIO) +#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 PNGAPI + * 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; + 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. */ -#if defined(_WIN32_WCE) - if ( !ReadFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) ) - check = 0; -#else - check = (png_size_t)fread(data, (png_size_t)1, length, - (png_FILE_p)png_ptr->io_ptr); -#endif + check = fread(data, 1, length, (png_FILE_p)png_ptr->io_ptr); if (check != length) png_error(png_ptr, "Read Error"); } -#else -/* this is the model-independent version. Since the standard I/O library +# 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. */ @@ -70,80 +72,88 @@ png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length) #define NEAR_BUF_SIZE 1024 #define MIN(a,b) (a <= b ? a : b) -static void PNGAPI +static void PNGCBAPI png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length) { - int check; + png_size_t check; png_byte *n_data; png_FILE_p io_ptr; - if(png_ptr == NULL) return; + 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) { -#if defined(_WIN32_WCE) - if ( !ReadFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) ) - check = 0; -#else check = fread(n_data, 1, length, io_ptr); -#endif } + else { png_byte buf[NEAR_BUF_SIZE]; png_size_t read, remaining, err; check = 0; remaining = length; + do { read = MIN(NEAR_BUF_SIZE, remaining); -#if defined(_WIN32_WCE) - if ( !ReadFile((HANDLE)(io_ptr), buf, read, &err, NULL) ) - err = 0; -#else - err = fread(buf, (png_size_t)1, read, io_ptr); -#endif + err = fread(buf, 1, read, io_ptr); png_memcpy(data, buf, read); /* copy far buffer to near buffer */ - if(err != read) + + if (err != read) break; + else check += err; + data += read; remaining -= read; } while (remaining != 0); } + if ((png_uint_32)check != (png_uint_32)length) png_error(png_ptr, "read Error"); } -#endif +# 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"). */ + * 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 png_set_read_fn(png_structp png_ptr, png_voidp io_ptr, png_rw_ptr read_data_fn) { - if(png_ptr == NULL) return; + if (png_ptr == NULL) + return; + png_ptr->io_ptr = io_ptr; -#if !defined(PNG_NO_STDIO) +#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 @@ -155,12 +165,11 @@ png_set_read_fn(png_structp png_ptr, png_voidp io_ptr, { png_ptr->write_data_fn = NULL; png_warning(png_ptr, - "It's an error to set both read_data_fn and write_data_fn in the "); - png_warning(png_ptr, - "same structure. Resetting write_data_fn to NULL."); + "Can't set both read_data_fn and write_data_fn in the" + " same structure"); } -#if defined(PNG_WRITE_FLUSH_SUPPORTED) +#ifdef PNG_WRITE_FLUSH_SUPPORTED png_ptr->output_flush_fn = NULL; #endif }