diff options
Diffstat (limited to 'lib/libutil/expand_number.c')
-rw-r--r-- | lib/libutil/expand_number.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/lib/libutil/expand_number.c b/lib/libutil/expand_number.c new file mode 100644 index 0000000..5d55884 --- /dev/null +++ b/lib/libutil/expand_number.c @@ -0,0 +1,101 @@ +/*- + * Copyright (c) 2007 Eric Anderson <anderson@FreeBSD.org> + * Copyright (c) 2007 Pawel Jakub Dawidek <pjd@FreeBSD.org> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/types.h> +#include <ctype.h> +#include <errno.h> +#include <inttypes.h> +#include <libutil.h> +#include <stdint.h> + +/* + * Convert an expression of the following forms to a uint64_t. + * 1) A positive decimal number. + * 2) A positive decimal number followed by a 'b' or 'B' (mult by 1). + * 3) A positive decimal number followed by a 'k' or 'K' (mult by 1 << 10). + * 4) A positive decimal number followed by a 'm' or 'M' (mult by 1 << 20). + * 5) A positive decimal number followed by a 'g' or 'G' (mult by 1 << 30). + * 6) A positive decimal number followed by a 't' or 'T' (mult by 1 << 40). + * 7) A positive decimal number followed by a 'p' or 'P' (mult by 1 << 50). + * 8) A positive decimal number followed by a 'e' or 'E' (mult by 1 << 60). + */ +int +expand_number(const char *buf, uint64_t *num) +{ + uint64_t number; + unsigned shift; + char *endptr; + + number = strtoumax(buf, &endptr, 0); + + if (endptr == buf) { + /* No valid digits. */ + errno = EINVAL; + return (-1); + } + + switch (tolower((unsigned char)*endptr)) { + case 'e': + shift = 60; + break; + case 'p': + shift = 50; + break; + case 't': + shift = 40; + break; + case 'g': + shift = 30; + break; + case 'm': + shift = 20; + break; + case 'k': + shift = 10; + break; + case 'b': + case '\0': /* No unit. */ + *num = number; + return (0); + default: + /* Unrecognized unit. */ + errno = EINVAL; + return (-1); + } + + if ((number << shift) >> shift != number) { + /* Overflow */ + errno = ERANGE; + return (-1); + } + + *num = number << shift; + return (0); +} |