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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	lib/libutil/fmt_scaled.c	Lines:	102	108	94.4 %
Date:	2017-11-13	Branches:	78	86	90.7 %


/*	$OpenBSD: fmt_scaled.c,v 1.16 2017/03/16 02:40:46 dtucker Exp $	*/

/*
 * Copyright (c) 2001, 2002, 2003 Ian F. Darwin.  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.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

/*
 * fmt_scaled: Format numbers scaled for human comprehension
 * scan_scaled: Scan numbers in this format.
 *
 * "Human-readable" output uses 4 digits max, and puts a unit suffix at
 * the end.  Makes output compact and easy-to-read esp. on huge disks.
 * Formatting code was originally in OpenBSD "df", converted to library routine.
 * Scanning code written for OpenBSD libutil.
 */

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <ctype.h>
#include <limits.h>

#include "util.h"

typedef enum {
	NONE = 0, KILO = 1, MEGA = 2, GIGA = 3, TERA = 4, PETA = 5, EXA = 6
} unit_type;

/* These three arrays MUST be in sync!  XXX make a struct */
static unit_type units[] = { NONE, KILO, MEGA, GIGA, TERA, PETA, EXA };
static char scale_chars[] = "BKMGTPE";
static long long scale_factors[] = {
	1LL,
	1024LL,
	1024LL*1024,
	1024LL*1024*1024,
	1024LL*1024*1024*1024,
	1024LL*1024*1024*1024*1024,
	1024LL*1024*1024*1024*1024*1024,
};
#define	SCALE_LENGTH (sizeof(units)/sizeof(units[0]))

#define MAX_DIGITS (SCALE_LENGTH * 3)	/* XXX strlen(sprintf("%lld", -1)? */

/* Convert the given input string "scaled" into numeric in "result".
 * Return 0 on success, -1 and errno set on error.
 */
int
scan_scaled(char *scaled, long long *result)
{
	char *p = scaled;
	int sign = 0;
	unsigned int i, ndigits = 0, fract_digits = 0;
	long long scale_fact = 1, whole = 0, fpart = 0;

	/* Skip leading whitespace */
	while (isascii((unsigned char)*p) && isspace((unsigned char)*p))
		++p;

	/* Then at most one leading + or - */
	while (*p == '-' || *p == '+') {
		if (*p == '-') {
			if (sign) {
				errno = EINVAL;
				return -1;
			}
			sign = -1;
			++p;
		} else if (*p == '+') {
			if (sign) {
				errno = EINVAL;
				return -1;
			}
			sign = +1;
			++p;
		}
	}

	/* Main loop: Scan digits, find decimal point, if present.
	 * We don't allow exponentials, so no scientific notation
	 * (but note that E for Exa might look like e to some!).
	 * Advance 'p' to end, to get scale factor.
	 */
	for (; isascii((unsigned char)*p) &&
	    (isdigit((unsigned char)*p) || *p=='.'); ++p) {
		if (*p == '.') {
			if (fract_digits > 0) {	/* oops, more than one '.' */
				errno = EINVAL;
				return -1;
			}
			fract_digits = 1;
			continue;
		}

		i = (*p) - '0';			/* whew! finally a digit we can use */
		if (fract_digits > 0) {
			if (fract_digits >= MAX_DIGITS-1)
				/* ignore extra fractional digits */
				continue;
			fract_digits++;		/* for later scaling */
			if (fpart > LLONG_MAX / 10) {
				errno = ERANGE;
				return -1;
			}
			fpart *= 10;
			if (i > LLONG_MAX - fpart) {
				errno = ERANGE;
				return -1;
			}
			fpart += i;
		} else {				/* normal digit */
			if (++ndigits >= MAX_DIGITS) {
				errno = ERANGE;
				return -1;
			}
			if (whole > LLONG_MAX / 10) {
				errno = ERANGE;
				return -1;
			}
			whole *= 10;
			if (i > LLONG_MAX - whole) {
				errno = ERANGE;
				return -1;
			}
			whole += i;
		}
	}

	if (sign) {
		whole *= sign;
		fpart *= sign;
	}

	/* If no scale factor given, we're done. fraction is discarded. */
	if (!*p) {
		*result = whole;
		return 0;
	}

	/* Validate scale factor, and scale whole and fraction by it. */
	for (i = 0; i < SCALE_LENGTH; i++) {

		/* Are we there yet? */
		if (*p == scale_chars[i] ||
			*p == tolower((unsigned char)scale_chars[i])) {

			/* If it ends with alphanumerics after the scale char, bad. */
			if (isalnum((unsigned char)*(p+1))) {
				errno = EINVAL;
				return -1;
			}
			scale_fact = scale_factors[i];

			/* check for overflow and underflow after scaling */
			if (whole > LLONG_MAX / scale_fact ||
			    whole < LLONG_MIN / scale_fact) {
				errno = ERANGE;
				return -1;
			}

			/* scale whole part */
			whole *= scale_fact;

			/* truncate fpart so it does't overflow.
			 * then scale fractional part.
			 */
			while (fpart >= LLONG_MAX / scale_fact) {
				fpart /= 10;
				fract_digits--;
			}
			fpart *= scale_fact;
			if (fract_digits > 0) {
				for (i = 0; i < fract_digits -1; i++)
					fpart /= 10;
			}
			whole += fpart;
			*result = whole;
			return 0;
		}
	}

	/* Invalid unit or character */
	errno = EINVAL;
	return -1;
}

/* Format the given "number" into human-readable form in "result".
 * Result must point to an allocated buffer of length FMT_SCALED_STRSIZE.
 * Return 0 on success, -1 and errno set if error.
 */
int
fmt_scaled(long long number, char *result)
{
	long long abval, fract = 0;
	unsigned int i;
	unit_type unit = NONE;

	abval = llabs(number);

	/* Not every negative long long has a positive representation.
	 * Also check for numbers that are just too darned big to format
	 */
	if (abval < 0 || abval / 1024 >= scale_factors[SCALE_LENGTH-1]) {
		errno = ERANGE;
		return -1;
	}

	/* scale whole part; get unscaled fraction */
	for (i = 0; i < SCALE_LENGTH; i++) {
		if (abval/1024 < scale_factors[i]) {
			unit = units[i];
			fract = (i == 0) ? 0 : abval % scale_factors[i];
			number /= scale_factors[i];
			if (i > 0)
				fract /= scale_factors[i - 1];
			break;
		}
	}

	fract = (10 * fract + 512) / 1024;
	/* if the result would be >= 10, round main number */
	if (fract == 10) {
		if (number >= 0)
			number++;
		else
			number--;
		fract = 0;
	}

	if (number == 0)
		strlcpy(result, "0B", FMT_SCALED_STRSIZE);
	else if (unit == NONE || number >= 100 || number <= -100) {
		if (fract >= 5) {
			if (number >= 0)
				number++;
			else
				number--;
		}
		(void)snprintf(result, FMT_SCALED_STRSIZE, "%lld%c",
			number, scale_chars[unit]);
	} else
		(void)snprintf(result, FMT_SCALED_STRSIZE, "%lld.%1lld%c",
			number, fract, scale_chars[unit]);

	return 0;
}

#ifdef	MAIN
/*
 * This is the original version of the program in the man page.
 * Copy-and-paste whatever you need from it.
 */
int
main(int argc, char **argv)
{
	char *cinput = "1.5K", buf[FMT_SCALED_STRSIZE];
	long long ninput = 10483892, result;

	if (scan_scaled(cinput, &result) == 0)
		printf("\"%s\" -> %lld\n", cinput, result);
	else
		perror(cinput);

	if (fmt_scaled(ninput, buf) == 0)
		printf("%lld -> \"%s\"\n", ninput, buf);
	else
		fprintf(stderr, "%lld invalid (%s)\n", ninput, strerror(errno));

	return 0;
}
#endif


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: fmt_scaled.c,v 1.16 2017/03/16 02:40:46 dtucker Exp $ */
2
3			/*
4			* Copyright (c) 2001, 2002, 2003 Ian F. Darwin. All rights reserved.
5			*
6			* Redistribution and use in source and binary forms, with or without
7			* modification, are permitted provided that the following conditions
8			* are met:
9			* 1. Redistributions of source code must retain the above copyright
10			* notice, this list of conditions and the following disclaimer.
11			* 2. Redistributions in binary form must reproduce the above copyright
12			* notice, this list of conditions and the following disclaimer in the
13			* documentation and/or other materials provided with the distribution.
14			* 3. The name of the author may not be used to endorse or promote products
15			* derived from this software without specific prior written permission.
16			*
17			* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18			* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19			* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20			* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21			* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22			* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23			* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24			* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25			* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26			* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27			*/
28
29			/*
30			* fmt_scaled: Format numbers scaled for human comprehension
31			* scan_scaled: Scan numbers in this format.
32			*
33			* "Human-readable" output uses 4 digits max, and puts a unit suffix at
34			* the end. Makes output compact and easy-to-read esp. on huge disks.
35			* Formatting code was originally in OpenBSD "df", converted to library routine.
36			* Scanning code written for OpenBSD libutil.
37			*/
38
39			#include <stdio.h>
40			#include <stdlib.h>
41			#include <errno.h>
42			#include <string.h>
43			#include <ctype.h>
44			#include <limits.h>
45
46			#include "util.h"
47
48			typedef enum {
49			NONE = 0, KILO = 1, MEGA = 2, GIGA = 3, TERA = 4, PETA = 5, EXA = 6
50			} unit_type;
51
52			/* These three arrays MUST be in sync! XXX make a struct */
53			static unit_type units[] = { NONE, KILO, MEGA, GIGA, TERA, PETA, EXA };
54			static char scale_chars[] = "BKMGTPE";
55			static long long scale_factors[] = {
56			1LL,
57			1024LL,
58			1024LL*1024,
59			1024LL10241024,
60			1024LL10241024*1024,
61			1024LL1024102410241024,
62			1024LL1024102410241024*1024,
63			};
64			#define SCALE_LENGTH (sizeof(units)/sizeof(units[0]))
65
66			#define MAX_DIGITS (SCALE_LENGTH * 3) /* XXX strlen(sprintf("%lld", -1)? */
67
68			/* Convert the given input string "scaled" into numeric in "result".
69			* Return 0 on success, -1 and errno set on error.
70			*/
71			int
72			scan_scaled(char scaled, long long result)
73			{
74			char *p = scaled;
75			int sign = 0;
76			unsigned int i, ndigits = 0, fract_digits = 0;
77			long long scale_fact = 1, whole = 0, fpart = 0;
78
79			/* Skip leading whitespace */
80	✓✗✓✓	591	while (isascii((unsigned char)p) && isspace((unsigned char)p))
81		21	++p;
82
83			/* Then at most one leading + or - */
84	✓✓✓✓	468	while (p == '-' \|\| p == '+') {
85	✓✓	42	if (*p == '-') {
86	✓✓	36	if (sign) {
87		3	errno = EINVAL;
88		3	return -1;
89			}
90			sign = -1;
91		33	++p;
92	✓✗	39	} else if (*p == '+') {
93	✓✓	6	if (sign) {
94		3	errno = EINVAL;
95		3	return -1;
96			}
97			sign = +1;
98		3	++p;
99		3	}
100			}
101
102			/* Main loop: Scan digits, find decimal point, if present.
103			* We don't allow exponentials, so no scientific notation
104			* (but note that E for Exa might look like e to some!).
105			* Advance 'p' to end, to get scale factor.
106			*/
107	✓✗✓✓	2922	for (; isascii((unsigned char)*p) &&
108	✓✓	2796	(isdigit((unsigned char)p) \|\| p=='.'); ++p) {
109	✓✓	1284	if (*p == '.') {
110	✓✓	48	if (fract_digits > 0) { /* oops, more than one '.' */
111		3	errno = EINVAL;
112		3	return -1;
113			}
114			fract_digits = 1;
115		45	continue;
116			}
117
118		1236	i = (p) - '0'; / whew! finally a digit we can use */
119	✓✓	1236	if (fract_digits > 0) {
120	✓✓	288	if (fract_digits >= MAX_DIGITS-1)
121			/* ignore extra fractional digits */
122			continue;
123		255	fract_digits++; /* for later scaling */
124	✗✓	255	if (fpart > LLONG_MAX / 10) {
125			errno = ERANGE;
126			return -1;
127			}
128		255	fpart *= 10;
129	✗✓	255	if (i > LLONG_MAX - fpart) {
130			errno = ERANGE;
131			return -1;
132			}
133		255	fpart += i;
134		255	} else { /* normal digit */
135	✗✓	948	if (++ndigits >= MAX_DIGITS) {
136			errno = ERANGE;
137			return -1;
138			}
139	✓✓	948	if (whole > LLONG_MAX / 10) {
140		6	errno = ERANGE;
141		6	return -1;
142			}
143		942	whole *= 10;
144	✓✓	942	if (i > LLONG_MAX - whole) {
145		15	errno = ERANGE;
146		15	return -1;
147			}
148		927	whole += i;
149			}
150			}
151
152	✓✓	102	if (sign) {
153		18	whole *= sign;
154		18	fpart *= sign;
155		18	}
156
157			/* If no scale factor given, we're done. fraction is discarded. */
158	✓✓	102	if (!*p) {
159		30	*result = whole;
160		30	return 0;
161			}
162
163			/* Validate scale factor, and scale whole and fraction by it. */
164	✓✓	540	for (i = 0; i < SCALE_LENGTH; i++) {
165
166			/* Are we there yet? */
167	✓✓✓✓	468	if (*p == scale_chars[i] \|\|
168		207	*p == tolower((unsigned char)scale_chars[i])) {
169
170			/* If it ends with alphanumerics after the scale char, bad. */
171	✓✓	63	if (isalnum((unsigned char)*(p+1))) {
172		6	errno = EINVAL;
173		6	return -1;
174			}
175		57	scale_fact = scale_factors[i];
176
177			/* check for overflow and underflow after scaling */
178	✓✓✓✓	111	if (whole > LLONG_MAX / scale_fact \|\|
179		54	whole < LLONG_MIN / scale_fact) {
180		6	errno = ERANGE;
181		6	return -1;
182			}
183
184			/* scale whole part */
185		51	whole *= scale_fact;
186
187			/* truncate fpart so it does't overflow.
188			* then scale fractional part.
189			*/
190	✓✓	168	while (fpart >= LLONG_MAX / scale_fact) {
191		33	fpart /= 10;
192		33	fract_digits--;
193			}
194		51	fpart *= scale_fact;
195	✓✓	51	if (fract_digits > 0) {
196	✓✓	468	for (i = 0; i < fract_digits -1; i++)
197		204	fpart /= 10;
198			}
199		51	whole += fpart;
200		51	*result = whole;
201		51	return 0;
202			}
203			}
204
205			/* Invalid unit or character */
206		9	errno = EINVAL;
207		9	return -1;
208		132	}
209
210			/* Format the given "number" into human-readable form in "result".
211			* Result must point to an allocated buffer of length FMT_SCALED_STRSIZE.
212			* Return 0 on success, -1 and errno set if error.
213			*/
214			int
215			fmt_scaled(long long number, char *result)
216			{
217			long long abval, fract = 0;
218			unsigned int i;
219			unit_type unit = NONE;
220
221		234	abval = llabs(number);
222
223			/* Not every negative long long has a positive representation.
224			* Also check for numbers that are just too darned big to format
225			*/
226	✓✓✗✓	231	if (abval < 0 \|\| abval / 1024 >= scale_factors[SCALE_LENGTH-1]) {
227		3	errno = ERANGE;
228		3	return -1;
229			}
230
231			/* scale whole part; get unscaled fraction */
232	✓✗	546	for (i = 0; i < SCALE_LENGTH; i++) {
233	✓✓	273	if (abval/1024 < scale_factors[i]) {
234		114	unit = units[i];
235	✓✓	315	fract = (i == 0) ? 0 : abval % scale_factors[i];
236		114	number /= scale_factors[i];
237	✓✓	114	if (i > 0)
238		87	fract /= scale_factors[i - 1];
239			break;
240			}
241			}
242
243		114	fract = (10 * fract + 512) / 1024;
244			/* if the result would be >= 10, round main number */
245	✓✓	114	if (fract == 10) {
246	✓✓	9	if (number >= 0)
247		6	number++;
248			else
249		3	number--;
250			fract = 0;
251		9	}
252
253	✓✓	114	if (number == 0)
254		3	strlcpy(result, "0B", FMT_SCALED_STRSIZE);
255	✓✓	111	else if (unit == NONE \|\| number >= 100 \|\| number <= -100) {
256	✓✓	48	if (fract >= 5) {
257	✓✓	18	if (number >= 0)
258		15	number++;
259			else
260		3	number--;
261			}
262		48	(void)snprintf(result, FMT_SCALED_STRSIZE, "%lld%c",
263		48	number, scale_chars[unit]);
264		48	} else
265		63	(void)snprintf(result, FMT_SCALED_STRSIZE, "%lld.%1lld%c",
266		63	number, fract, scale_chars[unit]);
267
268		114	return 0;
269		117	}
270
271			#ifdef MAIN
272			/*
273			* This is the original version of the program in the man page.
274			* Copy-and-paste whatever you need from it.
275			*/
276			int
277			main(int argc, char **argv)
278			{
279			char *cinput = "1.5K", buf[FMT_SCALED_STRSIZE];
280			long long ninput = 10483892, result;
281
282			if (scan_scaled(cinput, &result) == 0)
283			printf("\"%s\" -> %lld\n", cinput, result);
284			else
285			perror(cinput);
286
287			if (fmt_scaled(ninput, buf) == 0)
288			printf("%lld -> \"%s\"\n", ninput, buf);
289			else
290			fprintf(stderr, "%lld invalid (%s)\n", ninput, strerror(errno));
291
292			return 0;
293			}
294			#endif