X-Git-Url: https://plomlompom.com/repos/?a=blobdiff_plain;f=src%2Freadwrite.c;h=5b318524619d53180055f8aafbc489f9292827e5;hb=951248dddace9f7cadcf30700a3c3e6ad7ae2888;hp=da5f73fd962dda486b0dc832d9addd365ac91903;hpb=6ba18516a602b3d4ad95981887ad9c5eb40a335a;p=plomrogue diff --git a/src/readwrite.c b/src/readwrite.c index da5f73f..5b31852 100644 --- a/src/readwrite.c +++ b/src/readwrite.c @@ -6,29 +6,29 @@ -/* Read/write "x" from/to "file" as bigendian representation of "size" bits. - * Only multiples of 8 allowed for "size". On failure, return 1, else 0. +/* Read/write "x" from/to "file" as bigendian representation of "size" bits. On + * failure, return 1, else 0. (As of of now, all extern read/write functions + * build on top of these.) * - * As of of now, all other read/write functions build on top of these. TODO: - * Consider externing these so-far internal functions and dropping the - * interfaces to them, instead relying on their internal validity checks. - * (Usage of padded memory copies instead of directly manipulating * x as is - * done in read_uint* would need to be added, though.) + * Only use multiples of 8 greater or equal 32 for "size", so that storage + * inside uint32_t is possible. Originally a bit number check prefaced the code + * of both functions. It was removed as redundant due to all possible "size" + * values being hardcoded into the library (i.e. in all extern functions calling + * / wrapping around either function). If this ever changes, (re-)insert: + * + * if (0 == size || size > 32 || 0 != size % 8) + * { + * return 1; + * } */ static uint8_t read_uintX_bigendian(FILE * file, uint32_t * x, uint8_t size); static uint8_t write_uintX_bigendian(FILE * file, uint32_t x, uint8_t size); - static uint8_t read_uintX_bigendian(FILE * file, uint32_t * x, uint8_t size) { - if (0 != size % 8) /* This bit number validity check is redundant */ - { /* as long as this function is only available */ - return 1; /* through extern interfaces pre-defining the */ - } /* bit number. TODO: Consider dropping it. */ - int16_t bitshift = size - 8; - * x = 0; + int16_t bitshift = size - 8; int test; for (; bitshift >= 0; bitshift = bitshift - 8) { @@ -46,12 +46,7 @@ static uint8_t read_uintX_bigendian(FILE * file, uint32_t * x, uint8_t size) static uint8_t write_uintX_bigendian(FILE * file, uint32_t x, uint8_t size) { - if (0 != size % 8) /* See comment */ - { /* on identical */ - return 1; /* code block in */ - } /* read_uintX_bigendian(). */ int16_t bitshift = size - 8; - for (; bitshift >= 0; bitshift = bitshift - 8) { if (EOF == fputc((x >> bitshift) & 0xFF, file)) @@ -79,7 +74,7 @@ extern uint8_t read_uint8(FILE * file, uint8_t * x) extern uint8_t read_uint16_bigendian(FILE * file, uint16_t * x) { - /* See read_uint8() introductory comment for rationale. */ + /* See read_uint8() introductory code comment for rationale. */ uint32_t y = * x; uint8_t err = read_uintX_bigendian(file, &y, 16); * x = (uint16_t) y;