diff options
Diffstat (limited to 'pngpriv.h')
| -rw-r--r-- | pngpriv.h | 31 |
1 files changed, 15 insertions, 16 deletions
@@ -556,14 +556,14 @@ #endif /* These macros may need to be architecture dependent. */ -#define PNG_ALIGN_NONE 0 /* do not use data alignment */ -#define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */ +#define PNG_ALIGN_NONE 0 /* do not use data alignment */ +#define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */ #ifdef offsetof -# define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */ +# define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */ #else # define PNG_ALIGN_OFFSET -1 /* prevent the use of this */ #endif -#define PNG_ALIGN_SIZE 3 /* use sizeof to determine alignment */ +#define PNG_ALIGN_SIZE 3 /* use sizeof to determine alignment */ #ifndef PNG_ALIGN_TYPE /* Default to using aligned access optimizations and requiring alignment to a @@ -577,26 +577,25 @@ /* This is used because in some compiler implementations non-aligned * structure members are supported, so the offsetof approach below fails. * Set PNG_ALIGN_SIZE=0 for compiler combinations where unaligned access - * is good for performance. Do not do this unless you have tested the result - * and understand it. + * is good for performance. Do not do this unless you have tested the + * result and understand it. */ -# define png_alignof(type) (sizeof (type)) +# define png_alignof(type) (sizeof(type)) #else # if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET -# define png_alignof(type) offsetof(struct{char c; type t;}, t) +# define png_alignof(type) offsetof(struct{char c; type t;}, t) # else -# if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS -# define png_alignof(type) (1) -# endif - /* Else leave png_alignof undefined to prevent use thereof */ +# if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS +# define png_alignof(type) 1 +# endif + /* Else leave png_alignof undefined to prevent use thereof */ # endif #endif -/* This implicitly assumes alignment is always to a power of 2. */ +/* This implicitly assumes alignment is always a multiple of 2. */ #ifdef png_alignof -# define png_isaligned(ptr, type)\ - (((type)((const char*)ptr-(const char*)0) & \ - (type)(png_alignof(type)-1)) == 0) +# define png_isaligned(ptr, type) \ + (((type)(size_t)((const void*)(ptr)) & (type)(png_alignof(type)-1)) == 0) #else # define png_isaligned(ptr, type) 0 #endif |