Commit | Line | Data |
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1ec3d69b JA |
1 | #include <stdlib.h> |
2 | #include <stdio.h> | |
3 | #include <string.h> | |
4 | ||
5 | /* | |
6 | * Cheesy number->string conversion, complete with carry rounding error. | |
7 | */ | |
8 | char *num2str(unsigned long num, int maxlen, int base, int pow2) | |
9 | { | |
10 | char postfix[] = { ' ', 'K', 'M', 'G', 'P', 'E' }; | |
11 | unsigned int thousand[] = { 1000, 1024 }; | |
12 | unsigned int modulo, decimals; | |
05463816 JA |
13 | int post_index, carry = 0; |
14 | char tmp[32]; | |
1ec3d69b JA |
15 | char *buf; |
16 | ||
17 | buf = malloc(128); | |
18 | ||
19 | for (post_index = 0; base > 1; post_index++) | |
20 | base /= thousand[!!pow2]; | |
21 | ||
22 | modulo = -1U; | |
23 | while (post_index < sizeof(postfix)) { | |
24 | sprintf(tmp, "%lu", num); | |
25 | if (strlen(tmp) <= maxlen) | |
26 | break; | |
27 | ||
28 | modulo = num % thousand[!!pow2]; | |
29 | num /= thousand[!!pow2]; | |
05463816 | 30 | carry = modulo >= thousand[!!pow2] / 2; |
1ec3d69b JA |
31 | post_index++; |
32 | } | |
33 | ||
34 | if (modulo == -1U) { | |
35 | done: | |
36 | sprintf(buf, "%lu%c", num, postfix[post_index]); | |
37 | return buf; | |
38 | } | |
39 | ||
40 | sprintf(tmp, "%lu", num); | |
41 | decimals = maxlen - strlen(tmp); | |
05463816 JA |
42 | if (decimals <= 1) { |
43 | if (carry) | |
44 | num++; | |
1ec3d69b | 45 | goto done; |
05463816 JA |
46 | } |
47 | ||
48 | do { | |
49 | sprintf(tmp, "%u", modulo); | |
50 | if (strlen(tmp) <= decimals - 1) | |
51 | break; | |
52 | ||
53 | modulo = (modulo + 9) / 10; | |
54 | } while (1); | |
1ec3d69b | 55 | |
05463816 | 56 | sprintf(buf, "%lu.%u%c", num, modulo, postfix[post_index]); |
1ec3d69b JA |
57 | return buf; |
58 | } |