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Human readable size to bytes in C
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| #include <stdio.h> | |
| #include <stdlib.h> | |
| #include <inttypes.h> | |
| #include <errno.h> | |
| #include <string.h> | |
| static char *human_readable_suffix = "kMGT"; | |
| size_t *parse_human_readable(char *input, size_t *target) { | |
| char *endp = input; | |
| char *match = NULL; | |
| size_t shift = 0; | |
| errno = 0; | |
| long double value = strtold(input, &endp); | |
| if(errno || endp == input || value < 0) | |
| return NULL; | |
| if(!(match = strchr(human_readable_suffix, *endp))) | |
| return NULL; | |
| if(*match) | |
| shift = (match - human_readable_suffix + 1) * 10; | |
| *target = value * (1LU << shift); | |
| return target; | |
| } | |
| int test(char *input, size_t expected) { | |
| size_t value; | |
| if(!parse_human_readable(input, &value)) { | |
| if(expected == 0) | |
| return printf("%-6s => error (expected)\n", input); | |
| return printf("%-6s => error, expected: %lu\n", input, expected); | |
| } | |
| if(expected == value) | |
| return printf("%-6s => %14lu [ok, expected: %lu]\n", input, value, expected); | |
| return printf("%-6s => %14lu [error, expected: %lu]\n", input, value, expected); | |
| } | |
| int main(void) { | |
| test("1337", 1337); | |
| test("857.54", 857); | |
| test("128k", 128 * 1024); | |
| test("1.5k", 1536); | |
| test("8M", 8 * 1024 * 1024); | |
| test("0x55", 0x55); | |
| test("0x55k", 0x55 * 1024); | |
| test("1T", 1024 * 1024 * 1024 * 1024LU); | |
| test("32.", 32); | |
| test("-87", 0); | |
| test("abcd", 0); | |
| test("32x", 0); | |
| return 0; | |
| } |
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