parse_num.c revision d1154eb460efe588eaed3d439c1caaca149fa362 
1/*
2 * parse_num.c		- Parse the number of blocks
3 *
4 * Copyright (C) 2004,2005  Theodore Ts'o <tytso@mit.edu>
5 *
6 * %Begin-Header%
7 * This file may be redistributed under the terms of the GNU Library
8 * General Public License, version 2.
9 * %End-Header%
10 */
11
12#include "config.h"
13#include "e2p.h"
14
15#include <stdlib.h>
16
17unsigned long long parse_num_blocks2(const char *arg, int log_block_size)
18{
19	char *p;
20	unsigned long long num;
21
22	num = strtoull(arg, &p, 0);
23
24	if (p[0] && p[1])
25		return 0;
26
27	switch (*p) {		/* Using fall-through logic */
28	case 'T': case 't':
29		num <<= 10;
30		/* fallthrough */
31	case 'G': case 'g':
32		num <<= 10;
33		/* fallthrough */
34	case 'M': case 'm':
35		num <<= 10;
36		/* fallthrough */
37	case 'K': case 'k':
38		num >>= log_block_size;
39		break;
40	case 's':
41		num >>= (1+log_block_size);
42		break;
43	case '\0':
44		break;
45	default:
46		return 0;
47	}
48	return num;
49}
50
51unsigned long parse_num_blocks(const char *arg, int log_block_size)
52{
53	return parse_num_blocks2(arg, log_block_size);
54}
55
56#ifdef DEBUG
57#include <unistd.h>
58#include <stdio.h>
59
60main(int argc, char **argv)
61{
62	unsigned long num;
63	int log_block_size = 0;
64
65	if (argc != 2) {
66		fprintf(stderr, "Usage: %s arg\n", argv[0]);
67		exit(1);
68	}
69
70	num = parse_num_blocks(argv[1], log_block_size);
71
72	printf("Parsed number: %lu\n", num);
73	exit(0);
74}
75#endif
76