62e3c17b |
1 | /* |
2 | * Handling of the int64 and uint64 types. Done in 32-bit integers, |
3 | * for (pre-C99) portability. Hopefully once C99 becomes widespread |
4 | * we can kiss this lot goodbye... |
5 | */ |
6 | |
7 | #include <assert.h> |
8 | |
9 | typedef struct { |
10 | unsigned long hi, lo; |
11 | } uint64, int64; |
12 | |
32874aea |
13 | uint64 uint64_div10(uint64 x, int *remainder) |
14 | { |
62e3c17b |
15 | uint64 y; |
16 | int rem, r2; |
17 | y.hi = x.hi / 10; |
18 | y.lo = x.lo / 10; |
19 | rem = x.lo % 10; |
20 | /* |
21 | * Now we have to add in the remainder left over from x.hi. |
22 | */ |
23 | r2 = x.hi % 10; |
24 | y.lo += r2 * 2 * (0x80000000 / 10); |
25 | rem += r2 * 2 * (0x80000000 % 10); |
26 | y.lo += rem / 10; |
27 | rem %= 10; |
28 | |
29 | if (remainder) |
30 | *remainder = rem; |
31 | return y; |
32 | } |
33 | |
32874aea |
34 | void uint64_decimal(uint64 x, char *buffer) |
35 | { |
62e3c17b |
36 | char buf[20]; |
37 | int start = 20; |
38 | int d; |
39 | |
40 | while (x.hi || x.lo) { |
41 | x = uint64_div10(x, &d); |
42 | assert(start > 0); |
43 | buf[--start] = d + '0'; |
44 | } |
45 | |
32874aea |
46 | memcpy(buffer, buf + start, sizeof(buf) - start); |
47 | buffer[sizeof(buf) - start] = '\0'; |
62e3c17b |
48 | } |
49 | |
32874aea |
50 | uint64 uint64_make(unsigned long hi, unsigned long lo) |
51 | { |
62e3c17b |
52 | uint64 y; |
53 | y.hi = hi; |
54 | y.lo = lo; |
55 | return y; |
56 | } |
57 | |
32874aea |
58 | uint64 uint64_add(uint64 x, uint64 y) |
59 | { |
62e3c17b |
60 | x.lo += y.lo; |
61 | x.hi += y.hi + (x.lo < y.lo ? 1 : 0); |
62 | return x; |
63 | } |
64 | |
32874aea |
65 | uint64 uint64_add32(uint64 x, unsigned long y) |
66 | { |
62e3c17b |
67 | uint64 yy; |
68 | yy.hi = 0; |
69 | yy.lo = y; |
70 | return uint64_add(x, yy); |
71 | } |