diff options
Diffstat (limited to 'com32/lib/libpng/pngrio.c')
-rw-r--r-- | com32/lib/libpng/pngrio.c | 85 |
1 files changed, 52 insertions, 33 deletions
diff --git a/com32/lib/libpng/pngrio.c b/com32/lib/libpng/pngrio.c index cae501a5..6978682c 100644 --- a/com32/lib/libpng/pngrio.c +++ b/com32/lib/libpng/pngrio.c @@ -1,12 +1,15 @@ /* pngrio.c - functions for data input * - * libpng 1.2.8 - December 3, 2004 - * For conditions of distribution and use, see copyright notice in png.h - * Copyright (c) 1998-2004 Glenn Randers-Pehrson + * Last changed in libpng 1.2.43 [February 25, 2010] + * Copyright (c) 1998-2010 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 @@ -16,38 +19,45 @@ */ #define PNG_INTERNAL +#define PNG_NO_PEDANTIC_WARNINGS #include "png.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. */ + * 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. */ + * 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 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. */ -#if defined(_WIN32_WCE) +#ifdef _WIN32_WCE if ( !ReadFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) ) check = 0; #else @@ -59,7 +69,7 @@ png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length) png_error(png_ptr, "Read Error"); } #else -/* this is the model-independent version. Since the standard I/O library +/* 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. */ @@ -67,20 +77,23 @@ 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 /* PRIVATE */ +static void PNGAPI png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length) { int 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) { -#if defined(_WIN32_WCE) - if ( !ReadFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) ) +#ifdef _WIN32_WCE + if ( !ReadFile((HANDLE)(png_ptr->io_ptr), data, length, &check, + NULL) ) check = 0; #else check = fread(n_data, 1, length, io_ptr); @@ -95,14 +108,14 @@ png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length) do { read = MIN(NEAR_BUF_SIZE, remaining); -#if defined(_WIN32_WCE) +#ifdef _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 png_memcpy(data, buf, read); /* copy far buffer to near buffer */ - if(err != read) + if (err != read) break; else check += err; @@ -118,25 +131,30 @@ png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length) #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; 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 @@ -155,7 +173,8 @@ png_set_read_fn(png_structp png_ptr, png_voidp io_ptr, "same structure. Resetting write_data_fn to NULL."); } -#if defined(PNG_WRITE_FLUSH_SUPPORTED) +#ifdef PNG_WRITE_FLUSH_SUPPORTED png_ptr->output_flush_fn = NULL; #endif } +#endif /* PNG_READ_SUPPORTED */ |