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UUIDV4 in Odin
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package uuid4 | |
import "core:crypto" | |
import "core:io" | |
import "core:mem" | |
UUID_SIZE :: 16 | |
UUID4 :: distinct [UUID_SIZE]byte | |
generate :: proc() -> (u: UUID4) #no_bounds_check { | |
crypto.rand_bytes(u[:]) | |
u[6] = (u[6] & 0x0f) | (4 << 4) | |
u[8] = (u[8]&(0xff>>2) | (0x02 << 6)) | |
return u | |
} | |
to_string :: proc(dst: []byte, u: UUID4) #no_bounds_check { | |
u := u | |
assert(len(dst) >= 36, "dst not big enough for UUID4") | |
hex(dst[0:8], u[0:4]) | |
dst[8] = '-' | |
hex(dst[9:13], u[4:6]) | |
dst[13] = '-' | |
hex(dst[14:18], u[6:8]) | |
dst[18] = '-' | |
hex(dst[19:23], u[8:10]) | |
dst[23] = '-' | |
hex(dst[24:], u[10:]) | |
} | |
clone_to_string :: proc(u: UUID4, allocator := context.allocator) -> (str: string, err: mem.Allocator_Error) { | |
buf := make([]byte, 36, allocator) or_return | |
to_string(buf, u) | |
str = string(buf) | |
return | |
} | |
write :: proc(dst: io.Writer, u: UUID4, n_written: ^int = nil) -> (int, io.Error) { | |
buf: [36]byte | |
to_string(buf[:], u) | |
return io.write(dst, buf[:], n_written) | |
} | |
@(private) | |
HEXTABLE := [16]byte { | |
'0', '1', '2', '3', | |
'4', '5', '6', '7', | |
'8', '9', 'a', 'b', | |
'c', 'd', 'e', 'f', | |
} | |
@(private) | |
hex :: proc(dst, src: []byte) #no_bounds_check { | |
i := 0 | |
for v in src { | |
dst[i] = HEXTABLE[v>>4] | |
dst[i+1] = HEXTABLE[v&0x0f] | |
i+=2 | |
} | |
} | |
import "core:fmt" | |
main :: proc() { | |
fmt.println(clone_to_string(generate())) | |
} |
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