diff options
Diffstat (limited to 'Build/source/libs/libpng/libpng-src/png.c')
-rw-r--r-- | Build/source/libs/libpng/libpng-src/png.c | 101 |
1 files changed, 54 insertions, 47 deletions
diff --git a/Build/source/libs/libpng/libpng-src/png.c b/Build/source/libs/libpng/libpng-src/png.c index 9ed31570092..9a9fb23d942 100644 --- a/Build/source/libs/libpng/libpng-src/png.c +++ b/Build/source/libs/libpng/libpng-src/png.c @@ -14,7 +14,7 @@ #include "pngpriv.h" /* Generate a compiler error if there is an old png.h in the search path. */ -typedef png_libpng_version_1_6_43 Your_png_h_is_not_version_1_6_43; +typedef png_libpng_version_1_6_44 Your_png_h_is_not_version_1_6_44; /* Tells libpng that we have already handled the first "num_bytes" bytes * of the PNG file signature. If the PNG data is embedded into another @@ -794,7 +794,7 @@ png_get_copyright(png_const_structrp png_ptr) return PNG_STRING_COPYRIGHT #else return PNG_STRING_NEWLINE \ - "libpng version 1.6.43" PNG_STRING_NEWLINE \ + "libpng version 1.6.44" PNG_STRING_NEWLINE \ "Copyright (c) 2018-2024 Cosmin Truta" PNG_STRING_NEWLINE \ "Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson" \ PNG_STRING_NEWLINE \ @@ -1203,6 +1203,24 @@ png_colorspace_sync(png_const_structrp png_ptr, png_inforp info_ptr) #endif /* GAMMA */ #ifdef PNG_COLORSPACE_SUPPORTED +static int +png_safe_add(png_int_32 *addend0_and_result, png_int_32 addend1, + png_int_32 addend2) { + /* Safely add three integers. Returns 0 on success, 1 on overlow. + * IMPLEMENTATION NOTE: ANSI requires signed overflow not to occur, therefore + * relying on addition of two positive values producing a negative one is not + * safe. + */ + int addend0 = *addend0_and_result; + if (0x7fffffff - addend0 < addend1) + return 1; + addend0 += addend1; + if (0x7fffffff - addend1 < addend2) + return 1; + *addend0_and_result = addend0 + addend2; + return 0; +} + /* Added at libpng-1.5.5 to support read and write of true CIEXYZ values for * cHRM, as opposed to using chromaticities. These internal APIs return * non-zero on a parameter error. The X, Y and Z values are required to be @@ -1211,38 +1229,52 @@ png_colorspace_sync(png_const_structrp png_ptr, png_inforp info_ptr) static int png_xy_from_XYZ(png_xy *xy, const png_XYZ *XYZ) { - png_int_32 d, dwhite, whiteX, whiteY; + png_int_32 d, dred, dgreen, dwhite, whiteX, whiteY; - d = XYZ->red_X + XYZ->red_Y + XYZ->red_Z; + /* 'd' in each of the blocks below is just X+Y+Z for each component, + * x, y and z are X,Y,Z/(X+Y+Z). + */ + d = XYZ->red_X; + if (png_safe_add(&d, XYZ->red_Y, XYZ->red_Z)) + return 1; if (png_muldiv(&xy->redx, XYZ->red_X, PNG_FP_1, d) == 0) return 1; if (png_muldiv(&xy->redy, XYZ->red_Y, PNG_FP_1, d) == 0) return 1; - dwhite = d; + dred = d; whiteX = XYZ->red_X; whiteY = XYZ->red_Y; - d = XYZ->green_X + XYZ->green_Y + XYZ->green_Z; + d = XYZ->green_X; + if (png_safe_add(&d, XYZ->green_Y, XYZ->green_Z)) + return 1; if (png_muldiv(&xy->greenx, XYZ->green_X, PNG_FP_1, d) == 0) return 1; if (png_muldiv(&xy->greeny, XYZ->green_Y, PNG_FP_1, d) == 0) return 1; - dwhite += d; + dgreen = d; whiteX += XYZ->green_X; whiteY += XYZ->green_Y; - d = XYZ->blue_X + XYZ->blue_Y + XYZ->blue_Z; + d = XYZ->blue_X; + if (png_safe_add(&d, XYZ->blue_Y, XYZ->blue_Z)) + return 1; if (png_muldiv(&xy->bluex, XYZ->blue_X, PNG_FP_1, d) == 0) return 1; if (png_muldiv(&xy->bluey, XYZ->blue_Y, PNG_FP_1, d) == 0) return 1; - dwhite += d; whiteX += XYZ->blue_X; whiteY += XYZ->blue_Y; - /* The reference white is simply the sum of the end-point (X,Y,Z) vectors, - * thus: + /* The reference white is simply the sum of the end-point (X,Y,Z) vectors so + * the fillowing calculates (X+Y+Z) of the reference white (media white, + * encoding white) itself: */ + if (png_safe_add(&d, dred, dgreen)) + return 1; + + dwhite = d; + if (png_muldiv(&xy->whitex, whiteX, PNG_FP_1, dwhite) == 0) return 1; if (png_muldiv(&xy->whitey, whiteY, PNG_FP_1, dwhite) == 0) @@ -1257,20 +1289,6 @@ png_XYZ_from_xy(png_XYZ *XYZ, const png_xy *xy) png_fixed_point red_inverse, green_inverse, blue_scale; png_fixed_point left, right, denominator; - /* Check xy and, implicitly, z. Note that wide gamut color spaces typically - * have end points with 0 tristimulus values (these are impossible end - * points, but they are used to cover the possible colors). We check - * xy->whitey against 5, not 0, to avoid a possible integer overflow. - */ - if (xy->redx < 0 || xy->redx > PNG_FP_1) return 1; - if (xy->redy < 0 || xy->redy > PNG_FP_1-xy->redx) return 1; - if (xy->greenx < 0 || xy->greenx > PNG_FP_1) return 1; - if (xy->greeny < 0 || xy->greeny > PNG_FP_1-xy->greenx) return 1; - if (xy->bluex < 0 || xy->bluex > PNG_FP_1) return 1; - if (xy->bluey < 0 || xy->bluey > PNG_FP_1-xy->bluex) return 1; - if (xy->whitex < 0 || xy->whitex > PNG_FP_1) return 1; - if (xy->whitey < 5 || xy->whitey > PNG_FP_1-xy->whitex) return 1; - /* The reverse calculation is more difficult because the original tristimulus * value had 9 independent values (red,green,blue)x(X,Y,Z) however only 8 * derived values were recorded in the cHRM chunk; @@ -1451,16 +1469,16 @@ png_XYZ_from_xy(png_XYZ *XYZ, const png_xy *xy) * value of 2 indicates an internal error to the caller. */ if (png_muldiv(&left, xy->greenx-xy->bluex, xy->redy - xy->bluey, 7) == 0) - return 2; + return 1; if (png_muldiv(&right, xy->greeny-xy->bluey, xy->redx - xy->bluex, 7) == 0) - return 2; + return 1; denominator = left - right; /* Now find the red numerator. */ if (png_muldiv(&left, xy->greenx-xy->bluex, xy->whitey-xy->bluey, 7) == 0) - return 2; + return 1; if (png_muldiv(&right, xy->greeny-xy->bluey, xy->whitex-xy->bluex, 7) == 0) - return 2; + return 1; /* Overflow is possible here and it indicates an extreme set of PNG cHRM * chunk values. This calculation actually returns the reciprocal of the @@ -1473,9 +1491,9 @@ png_XYZ_from_xy(png_XYZ *XYZ, const png_xy *xy) /* Similarly for green_inverse: */ if (png_muldiv(&left, xy->redy-xy->bluey, xy->whitex-xy->bluex, 7) == 0) - return 2; + return 1; if (png_muldiv(&right, xy->redx-xy->bluex, xy->whitey-xy->bluey, 7) == 0) - return 2; + return 1; if (png_muldiv(&green_inverse, xy->whitey, denominator, left-right) == 0 || green_inverse <= xy->whitey) return 1; @@ -1520,25 +1538,14 @@ png_XYZ_from_xy(png_XYZ *XYZ, const png_xy *xy) static int png_XYZ_normalize(png_XYZ *XYZ) { - png_int_32 Y; + png_int_32 Y, Ytemp; - if (XYZ->red_Y < 0 || XYZ->green_Y < 0 || XYZ->blue_Y < 0 || - XYZ->red_X < 0 || XYZ->green_X < 0 || XYZ->blue_X < 0 || - XYZ->red_Z < 0 || XYZ->green_Z < 0 || XYZ->blue_Z < 0) + /* Normalize by scaling so the sum of the end-point Y values is PNG_FP_1. */ + Ytemp = XYZ->red_Y; + if (png_safe_add(&Ytemp, XYZ->green_Y, XYZ->blue_Y)) return 1; - /* Normalize by scaling so the sum of the end-point Y values is PNG_FP_1. - * IMPLEMENTATION NOTE: ANSI requires signed overflow not to occur, therefore - * relying on addition of two positive values producing a negative one is not - * safe. - */ - Y = XYZ->red_Y; - if (0x7fffffff - Y < XYZ->green_X) - return 1; - Y += XYZ->green_Y; - if (0x7fffffff - Y < XYZ->blue_X) - return 1; - Y += XYZ->blue_Y; + Y = Ytemp; if (Y != PNG_FP_1) { |