| 1 | /* (c) Magnus Auvinen. See licence.txt in the root of the distribution for more information. */ |
| 2 | /* If you are missing that file, acquire a complete release at teeworlds.com. */ |
| 3 | |
| 4 | #include "bytes.h" |
| 5 | |
| 6 | void swap_endian(void *data, unsigned elem_size, unsigned num) |
| 7 | { |
| 8 | char *src = (char *)data; |
| 9 | char *dst = src + (elem_size - 1); |
| 10 | |
| 11 | while(num) |
| 12 | { |
| 13 | unsigned n = elem_size >> 1; |
| 14 | char tmp; |
| 15 | while(n) |
| 16 | { |
| 17 | tmp = *src; |
| 18 | *src = *dst; |
| 19 | *dst = tmp; |
| 20 | |
| 21 | src++; |
| 22 | dst--; |
| 23 | n--; |
| 24 | } |
| 25 | |
| 26 | src = src + (elem_size >> 1); |
| 27 | dst = src + (elem_size - 1); |
| 28 | num--; |
| 29 | } |
| 30 | } |
| 31 | |
| 32 | static_assert(sizeof(unsigned) == 4, "unsigned must be 4 bytes in size" ); |
| 33 | static_assert(sizeof(unsigned) == sizeof(int), "unsigned and int must have the same size" ); |
| 34 | |
| 35 | unsigned bytes_be_to_uint(const unsigned char *bytes) |
| 36 | { |
| 37 | return ((bytes[0] & 0xffu) << 24u) | ((bytes[1] & 0xffu) << 16u) | ((bytes[2] & 0xffu) << 8u) | (bytes[3] & 0xffu); |
| 38 | } |
| 39 | |
| 40 | void uint_to_bytes_be(unsigned char *bytes, unsigned value) |
| 41 | { |
| 42 | bytes[0] = (value >> 24u) & 0xffu; |
| 43 | bytes[1] = (value >> 16u) & 0xffu; |
| 44 | bytes[2] = (value >> 8u) & 0xffu; |
| 45 | bytes[3] = value & 0xffu; |
| 46 | } |
| 47 | |