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-rw-r--r--src/3rdparty/freetype/src/sfnt/pngshim.c377
1 files changed, 377 insertions, 0 deletions
diff --git a/src/3rdparty/freetype/src/sfnt/pngshim.c b/src/3rdparty/freetype/src/sfnt/pngshim.c
new file mode 100644
index 0000000000..9bfcc2a779
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+++ b/src/3rdparty/freetype/src/sfnt/pngshim.c
@@ -0,0 +1,377 @@
+/***************************************************************************/
+/* */
+/* pngshim.c */
+/* */
+/* PNG Bitmap glyph support. */
+/* */
+/* Copyright 2013, 2014 by Google, Inc. */
+/* Written by Stuart Gill and Behdad Esfahbod. */
+/* */
+/* This file is part of the FreeType project, and may only be used, */
+/* modified, and distributed under the terms of the FreeType project */
+/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
+/* this file you indicate that you have read the license and */
+/* understand and accept it fully. */
+/* */
+/***************************************************************************/
+
+
+#include <ft2build.h>
+#include FT_INTERNAL_DEBUG_H
+#include FT_INTERNAL_STREAM_H
+#include FT_TRUETYPE_TAGS_H
+#include FT_CONFIG_STANDARD_LIBRARY_H
+
+
+#ifdef FT_CONFIG_OPTION_USE_PNG
+
+ /* We always include <stjmp.h>, so make libpng shut up! */
+#define PNG_SKIP_SETJMP_CHECK 1
+#include <png.h>
+#include "pngshim.h"
+
+#include "sferrors.h"
+
+
+ /* This code is freely based on cairo-png.c. There's so many ways */
+ /* to call libpng, and the way cairo does it is defacto standard. */
+
+ static int
+ multiply_alpha( int alpha,
+ int color )
+ {
+ int temp = ( alpha * color ) + 0x80;
+
+
+ return ( temp + ( temp >> 8 ) ) >> 8;
+ }
+
+
+ /* Premultiplies data and converts RGBA bytes => native endian. */
+ static void
+ premultiply_data( png_structp png,
+ png_row_infop row_info,
+ png_bytep data )
+ {
+ unsigned int i;
+
+ FT_UNUSED( png );
+
+
+ for ( i = 0; i < row_info->rowbytes; i += 4 )
+ {
+ unsigned char* base = &data[i];
+ unsigned int alpha = base[3];
+
+
+ if ( alpha == 0 )
+ base[0] = base[1] = base[2] = base[3] = 0;
+
+ else
+ {
+ unsigned int red = base[0];
+ unsigned int green = base[1];
+ unsigned int blue = base[2];
+
+
+ if ( alpha != 0xFF )
+ {
+ red = multiply_alpha( alpha, red );
+ green = multiply_alpha( alpha, green );
+ blue = multiply_alpha( alpha, blue );
+ }
+
+ base[0] = blue;
+ base[1] = green;
+ base[2] = red;
+ base[3] = alpha;
+ }
+ }
+ }
+
+
+ /* Converts RGBx bytes to BGRA. */
+ static void
+ convert_bytes_to_data( png_structp png,
+ png_row_infop row_info,
+ png_bytep data )
+ {
+ unsigned int i;
+
+ FT_UNUSED( png );
+
+
+ for ( i = 0; i < row_info->rowbytes; i += 4 )
+ {
+ unsigned char* base = &data[i];
+ unsigned int red = base[0];
+ unsigned int green = base[1];
+ unsigned int blue = base[2];
+
+
+ base[0] = blue;
+ base[1] = green;
+ base[2] = red;
+ base[3] = 0xFF;
+ }
+ }
+
+
+ /* Use error callback to avoid png writing to stderr. */
+ static void
+ error_callback( png_structp png,
+ png_const_charp error_msg )
+ {
+ FT_Error* error = (FT_Error*)png_get_error_ptr( png );
+
+ FT_UNUSED( error_msg );
+
+
+ *error = FT_THROW( Out_Of_Memory );
+#ifdef PNG_SETJMP_SUPPORTED
+ ft_longjmp( png_jmpbuf( png ), 1 );
+#endif
+ /* if we get here, then we have no choice but to abort ... */
+ }
+
+
+ /* Use warning callback to avoid png writing to stderr. */
+ static void
+ warning_callback( png_structp png,
+ png_const_charp error_msg )
+ {
+ FT_UNUSED( png );
+ FT_UNUSED( error_msg );
+
+ /* Just ignore warnings. */
+ }
+
+
+ static void
+ read_data_from_FT_Stream( png_structp png,
+ png_bytep data,
+ png_size_t length )
+ {
+ FT_Error error;
+ png_voidp p = png_get_io_ptr( png );
+ FT_Stream stream = (FT_Stream)p;
+
+
+ if ( FT_FRAME_ENTER( length ) )
+ {
+ FT_Error* e = (FT_Error*)png_get_error_ptr( png );
+
+
+ *e = FT_THROW( Invalid_Stream_Read );
+ png_error( png, NULL );
+
+ return;
+ }
+
+ memcpy( data, stream->cursor, length );
+
+ FT_FRAME_EXIT();
+ }
+
+
+ FT_LOCAL_DEF( FT_Error )
+ Load_SBit_Png( FT_GlyphSlot slot,
+ FT_Int x_offset,
+ FT_Int y_offset,
+ FT_Int pix_bits,
+ TT_SBit_Metrics metrics,
+ FT_Memory memory,
+ FT_Byte* data,
+ FT_UInt png_len,
+ FT_Bool populate_map_and_metrics )
+ {
+ FT_Bitmap *map = &slot->bitmap;
+ FT_Error error = FT_Err_Ok;
+ FT_StreamRec stream;
+
+ png_structp png;
+ png_infop info;
+ png_uint_32 imgWidth, imgHeight;
+
+ int bitdepth, color_type, interlace;
+ FT_Int i;
+ png_byte* *rows = NULL; /* pacify compiler */
+
+
+ if ( x_offset < 0 ||
+ y_offset < 0 )
+ {
+ error = FT_THROW( Invalid_Argument );
+ goto Exit;
+ }
+
+ if ( !populate_map_and_metrics &&
+ ( (FT_UInt)x_offset + metrics->width > map->width ||
+ (FT_UInt)y_offset + metrics->height > map->rows ||
+ pix_bits != 32 ||
+ map->pixel_mode != FT_PIXEL_MODE_BGRA ) )
+ {
+ error = FT_THROW( Invalid_Argument );
+ goto Exit;
+ }
+
+ FT_Stream_OpenMemory( &stream, data, png_len );
+
+ png = png_create_read_struct( PNG_LIBPNG_VER_STRING,
+ &error,
+ error_callback,
+ warning_callback );
+ if ( !png )
+ {
+ error = FT_THROW( Out_Of_Memory );
+ goto Exit;
+ }
+
+ info = png_create_info_struct( png );
+ if ( !info )
+ {
+ error = FT_THROW( Out_Of_Memory );
+ png_destroy_read_struct( &png, NULL, NULL );
+ goto Exit;
+ }
+
+ if ( ft_setjmp( png_jmpbuf( png ) ) )
+ {
+ error = FT_THROW( Invalid_File_Format );
+ goto DestroyExit;
+ }
+
+ png_set_read_fn( png, &stream, read_data_from_FT_Stream );
+
+ png_read_info( png, info );
+ png_get_IHDR( png, info,
+ &imgWidth, &imgHeight,
+ &bitdepth, &color_type, &interlace,
+ NULL, NULL );
+
+ if ( error ||
+ ( !populate_map_and_metrics &&
+ ( (FT_Int)imgWidth != metrics->width ||
+ (FT_Int)imgHeight != metrics->height ) ) )
+ goto DestroyExit;
+
+ if ( populate_map_and_metrics )
+ {
+ FT_Long size;
+
+
+ metrics->width = (FT_Int)imgWidth;
+ metrics->height = (FT_Int)imgHeight;
+
+ map->width = metrics->width;
+ map->rows = metrics->height;
+ map->pixel_mode = FT_PIXEL_MODE_BGRA;
+ map->pitch = map->width * 4;
+ map->num_grays = 256;
+
+ /* reject too large bitmaps similarly to the rasterizer */
+ if ( map->rows > 0x7FFF || map->width > 0x7FFF )
+ {
+ error = FT_THROW( Array_Too_Large );
+ goto DestroyExit;
+ }
+
+ /* this doesn't overflow: 0x7FFF * 0x7FFF * 4 < 2^32 */
+ size = map->rows * map->pitch;
+
+ error = ft_glyphslot_alloc_bitmap( slot, size );
+ if ( error )
+ goto DestroyExit;
+ }
+
+ /* convert palette/gray image to rgb */
+ if ( color_type == PNG_COLOR_TYPE_PALETTE )
+ png_set_palette_to_rgb( png );
+
+ /* expand gray bit depth if needed */
+ if ( color_type == PNG_COLOR_TYPE_GRAY )
+ {
+#if PNG_LIBPNG_VER >= 10209
+ png_set_expand_gray_1_2_4_to_8( png );
+#else
+ png_set_gray_1_2_4_to_8( png );
+#endif
+ }
+
+ /* transform transparency to alpha */
+ if ( png_get_valid(png, info, PNG_INFO_tRNS ) )
+ png_set_tRNS_to_alpha( png );
+
+ if ( bitdepth == 16 )
+ png_set_strip_16( png );
+
+ if ( bitdepth < 8 )
+ png_set_packing( png );
+
+ /* convert grayscale to RGB */
+ if ( color_type == PNG_COLOR_TYPE_GRAY ||
+ color_type == PNG_COLOR_TYPE_GRAY_ALPHA )
+ png_set_gray_to_rgb( png );
+
+ if ( interlace != PNG_INTERLACE_NONE )
+ png_set_interlace_handling( png );
+
+ png_set_filler( png, 0xFF, PNG_FILLER_AFTER );
+
+ /* recheck header after setting EXPAND options */
+ png_read_update_info(png, info );
+ png_get_IHDR( png, info,
+ &imgWidth, &imgHeight,
+ &bitdepth, &color_type, &interlace,
+ NULL, NULL );
+
+ if ( bitdepth != 8 ||
+ !( color_type == PNG_COLOR_TYPE_RGB ||
+ color_type == PNG_COLOR_TYPE_RGB_ALPHA ) )
+ {
+ error = FT_THROW( Invalid_File_Format );
+ goto DestroyExit;
+ }
+
+ switch ( color_type )
+ {
+ default:
+ /* Shouldn't happen, but fall through. */
+
+ case PNG_COLOR_TYPE_RGB_ALPHA:
+ png_set_read_user_transform_fn( png, premultiply_data );
+ break;
+
+ case PNG_COLOR_TYPE_RGB:
+ /* Humm, this smells. Carry on though. */
+ png_set_read_user_transform_fn( png, convert_bytes_to_data );
+ break;
+ }
+
+ if ( FT_NEW_ARRAY( rows, imgHeight ) )
+ {
+ error = FT_THROW( Out_Of_Memory );
+ goto DestroyExit;
+ }
+
+ for ( i = 0; i < (FT_Int)imgHeight; i++ )
+ rows[i] = map->buffer + ( y_offset + i ) * map->pitch + x_offset * 4;
+
+ png_read_image( png, rows );
+
+ FT_FREE( rows );
+
+ png_read_end( png, info );
+
+ DestroyExit:
+ png_destroy_read_struct( &png, &info, NULL );
+ FT_Stream_Close( &stream );
+
+ Exit:
+ return error;
+ }
+
+#endif /* FT_CONFIG_OPTION_USE_PNG */
+
+
+/* END */