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 | */ | |
73798eb2 | 8 | char *num2str(unsigned long num, int maxlen, int base, int pow2, int unit_base) |
1ec3d69b | 9 | { |
73798eb2 SN |
10 | const char *postfix[] = { "", "K", "M", "G", "P", "E" }; |
11 | const char *byte_postfix[] = { "", "B", "bit" }; | |
12 | const unsigned int thousand[] = { 1000, 1024 }; | |
1ec3d69b | 13 | unsigned int modulo, decimals; |
73798eb2 | 14 | int byte_post_index = 0, post_index, carry = 0; |
05463816 | 15 | char tmp[32]; |
1ec3d69b JA |
16 | char *buf; |
17 | ||
18 | buf = malloc(128); | |
19 | ||
20 | for (post_index = 0; base > 1; post_index++) | |
21 | base /= thousand[!!pow2]; | |
22 | ||
73798eb2 SN |
23 | switch (unit_base) { |
24 | case 1: | |
25 | byte_post_index = 2; | |
26 | num *= 8; | |
27 | break; | |
28 | case 8: | |
29 | byte_post_index = 1; | |
30 | break; | |
31 | } | |
32 | ||
1ec3d69b JA |
33 | modulo = -1U; |
34 | while (post_index < sizeof(postfix)) { | |
35 | sprintf(tmp, "%lu", num); | |
36 | if (strlen(tmp) <= maxlen) | |
37 | break; | |
38 | ||
39 | modulo = num % thousand[!!pow2]; | |
40 | num /= thousand[!!pow2]; | |
05463816 | 41 | carry = modulo >= thousand[!!pow2] / 2; |
1ec3d69b JA |
42 | post_index++; |
43 | } | |
44 | ||
45 | if (modulo == -1U) { | |
46 | done: | |
73798eb2 SN |
47 | sprintf(buf, "%lu%s%s", num, postfix[post_index], |
48 | byte_postfix[byte_post_index]); | |
1ec3d69b JA |
49 | return buf; |
50 | } | |
51 | ||
52 | sprintf(tmp, "%lu", num); | |
53 | decimals = maxlen - strlen(tmp); | |
05463816 JA |
54 | if (decimals <= 1) { |
55 | if (carry) | |
56 | num++; | |
1ec3d69b | 57 | goto done; |
05463816 JA |
58 | } |
59 | ||
60 | do { | |
61 | sprintf(tmp, "%u", modulo); | |
62 | if (strlen(tmp) <= decimals - 1) | |
63 | break; | |
64 | ||
65 | modulo = (modulo + 9) / 10; | |
66 | } while (1); | |
1ec3d69b | 67 | |
73798eb2 SN |
68 | sprintf(buf, "%lu.%u%s%s", num, modulo, postfix[post_index], |
69 | byte_postfix[byte_post_index]); | |
1ec3d69b JA |
70 | return buf; |
71 | } |