xref: /openbsd-src/usr.bin/top/utils.c (revision 0b7734b3d77bb9b21afec6f4621cae6c805dbd45)
1 /* $OpenBSD: utils.c,v 1.25 2015/01/16 06:40:13 deraadt Exp $	 */
2 
3 /*
4  *  Top users/processes display for Unix
5  *  Version 3
6  *
7  * Copyright (c) 1984, 1989, William LeFebvre, Rice University
8  * Copyright (c) 1989, 1990, 1992, William LeFebvre, Northwestern University
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR OR HIS EMPLOYER BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 /*
32  *  This file contains various handy utilities used by top.
33  */
34 
35 #include <sys/types.h>
36 #include <sys/sysctl.h>
37 #include <err.h>
38 #include <stdio.h>
39 #include <string.h>
40 #include <stdlib.h>
41 #include <stdint.h>
42 #include <limits.h>
43 
44 #include "top.h"
45 #include "machine.h"
46 #include "utils.h"
47 
48 int
49 atoiwi(char *str)
50 {
51 	size_t len;
52 	const char *errstr;
53 	int i;
54 
55 	len = strlen(str);
56 	if (len != 0) {
57 		if (strncmp(str, "infinity", len) == 0 ||
58 		    strncmp(str, "all", len) == 0 ||
59 		    strncmp(str, "maximum", len) == 0) {
60 			return (Infinity);
61 		}
62 		i = (int)strtonum(str, 0, INT_MAX, &errstr);
63 		if (errstr) {
64 			return (Invalid);
65 		} else
66 			return (i);
67 	}
68 	return (0);
69 }
70 
71 /*
72  * itoa - convert integer (decimal) to ascii string.
73  */
74 char *
75 itoa(int val)
76 {
77 	static char buffer[16];	/* result is built here */
78 
79 	/*
80 	 * 16 is sufficient since the largest number we will ever convert
81 	 * will be 2^32-1, which is 10 digits.
82 	 */
83 	(void)snprintf(buffer, sizeof(buffer), "%d", val);
84 	return (buffer);
85 }
86 
87 /*
88  * format_uid(uid) - like itoa, except for uid_t and the number is right
89  * justified in a 6 character field to match uname_field in top.c.
90  */
91 char *
92 format_uid(uid_t uid)
93 {
94 	static char buffer[16];	/* result is built here */
95 
96 	/*
97 	 * 16 is sufficient since the largest uid we will ever convert
98 	 * will be 2^32-1, which is 10 digits.
99 	 */
100 	(void)snprintf(buffer, sizeof(buffer), "%6u", uid);
101 	return (buffer);
102 }
103 
104 /*
105  * digits(val) - return number of decimal digits in val.  Only works for
106  * positive numbers.  If val <= 0 then digits(val) == 0.
107  */
108 int
109 digits(int val)
110 {
111 	int cnt = 0;
112 
113 	while (val > 0) {
114 		cnt++;
115 		val /= 10;
116 	}
117 	return (cnt);
118 }
119 
120 /*
121  * string_index(string, array) - find string in array and return index
122  */
123 int
124 string_index(char *string, char **array)
125 {
126 	int i = 0;
127 
128 	while (*array != NULL) {
129 		if (strncmp(string, *array, strlen(string)) == 0)
130 			return (i);
131 		array++;
132 		i++;
133 	}
134 	return (-1);
135 }
136 
137 /*
138  * argparse(line, cntp) - parse arguments in string "line", separating them
139  * out into an argv-like array, and setting *cntp to the number of
140  * arguments encountered.  This is a simple parser that doesn't understand
141  * squat about quotes.
142  */
143 char **
144 argparse(char *line, int *cntp)
145 {
146 	char **argv, **argarray, *args, *from, *to;
147 	int cnt, ch, length, lastch;
148 
149 	/*
150 	 * unfortunately, the only real way to do this is to go thru the
151 	 * input string twice.
152 	 */
153 
154 	/* step thru the string counting the white space sections */
155 	from = line;
156 	lastch = cnt = length = 0;
157 	while ((ch = *from++) != '\0') {
158 		length++;
159 		if (ch == ' ' && lastch != ' ')
160 			cnt++;
161 		lastch = ch;
162 	}
163 
164 	/*
165 	 * add three to the count:  one for the initial "dummy" argument, one
166 	 * for the last argument and one for NULL
167 	 */
168 	cnt += 3;
169 
170 	/* allocate a char * array to hold the pointers */
171 	if ((argarray = calloc(cnt, sizeof(char *))) == NULL)
172 		err(1, NULL);
173 
174 	/* allocate another array to hold the strings themselves */
175 	if ((args = malloc(length + 2)) == NULL)
176 		err(1, NULL);
177 
178 	/* initialization for main loop */
179 	from = line;
180 	to = args;
181 	argv = argarray;
182 	lastch = '\0';
183 
184 	/* create a dummy argument to keep getopt happy */
185 	*argv++ = to;
186 	*to++ = '\0';
187 	cnt = 2;
188 
189 	/* now build argv while copying characters */
190 	*argv++ = to;
191 	while ((ch = *from++) != '\0') {
192 		if (ch != ' ') {
193 			if (lastch == ' ') {
194 				*to++ = '\0';
195 				*argv++ = to;
196 				cnt++;
197 			}
198 			*to++ = ch;
199 		}
200 		lastch = ch;
201 	}
202 	*to++ = '\0';
203 
204 	/* set cntp and return the allocated array */
205 	*cntp = cnt;
206 	return (argarray);
207 }
208 
209 /*
210  * percentages(cnt, out, new, old, diffs) - calculate percentage change
211  * between array "old" and "new", putting the percentages in "out".
212  * "cnt" is size of each array and "diffs" is used for scratch space.
213  * The array "old" is updated on each call.
214  * The routine assumes modulo arithmetic.  This function is especially
215  * useful on BSD machines for calculating cpu state percentages.
216  */
217 int
218 percentages(int cnt, int64_t *out, int64_t *new, int64_t *old, int64_t *diffs)
219 {
220 	int64_t change, total_change, *dp, half_total;
221 	int i;
222 
223 	/* initialization */
224 	total_change = 0;
225 	dp = diffs;
226 
227 	/* calculate changes for each state and the overall change */
228 	for (i = 0; i < cnt; i++) {
229 		if ((change = *new - *old) < 0) {
230 			/* this only happens when the counter wraps */
231 			change = INT64_MAX - *old + *new;
232 		}
233 		total_change += (*dp++ = change);
234 		*old++ = *new++;
235 	}
236 
237 	/* avoid divide by zero potential */
238 	if (total_change == 0)
239 		total_change = 1;
240 
241 	/* calculate percentages based on overall change, rounding up */
242 	half_total = total_change / 2l;
243 	for (i = 0; i < cnt; i++)
244 		*out++ = ((*diffs++ * 1000 + half_total) / total_change);
245 
246 	/* return the total in case the caller wants to use it */
247 	return (total_change);
248 }
249 
250 /*
251  * format_time(seconds) - format number of seconds into a suitable display
252  * that will fit within 6 characters.  Note that this routine builds its
253  * string in a static area.  If it needs to be called more than once without
254  * overwriting previous data, then we will need to adopt a technique similar
255  * to the one used for format_k.
256  */
257 
258 /*
259  * Explanation: We want to keep the output within 6 characters.  For low
260  * values we use the format mm:ss.  For values that exceed 999:59, we switch
261  * to a format that displays hours and fractions:  hhh.tH.  For values that
262  * exceed 999.9, we use hhhh.t and drop the "H" designator.  For values that
263  * exceed 9999.9, we use "???".
264  */
265 
266 char *
267 format_time(time_t seconds)
268 {
269 	static char result[10];
270 
271 	/* sanity protection */
272 	if (seconds < 0 || seconds > (99999l * 360l)) {
273 		strlcpy(result, "   ???", sizeof result);
274 	} else if (seconds >= (1000l * 60l)) {
275 		/* alternate (slow) method displaying hours and tenths */
276 		snprintf(result, sizeof(result), "%5.1fH",
277 		    (double) seconds / (double) (60l * 60l));
278 
279 		/*
280 		 * It is possible that the snprintf took more than 6
281 		 * characters. If so, then the "H" appears as result[6].  If
282 		 * not, then there is a \0 in result[6].  Either way, it is
283 		 * safe to step on.
284 		 */
285 		result[6] = '\0';
286 	} else {
287 		/* standard method produces MMM:SS */
288 		/* we avoid printf as must as possible to make this quick */
289 		snprintf(result, sizeof(result), "%3d:%02d", (int)seconds / 60,
290 		    (int)seconds % 60);
291 	}
292 	return (result);
293 }
294 
295 /*
296  * format_k(amt) - format a kilobyte memory value, returning a string
297  * suitable for display.  Returns a pointer to a static
298  * area that changes each call.  "amt" is converted to a
299  * string with a trailing "K".  If "amt" is 10000 or greater,
300  * then it is formatted as megabytes (rounded) with a
301  * trailing "M".
302  */
303 
304 /*
305  * Compromise time.  We need to return a string, but we don't want the
306  * caller to have to worry about freeing a dynamically allocated string.
307  * Unfortunately, we can't just return a pointer to a static area as one
308  * of the common uses of this function is in a large call to snprintf where
309  * it might get invoked several times.  Our compromise is to maintain an
310  * array of strings and cycle thru them with each invocation.  We make the
311  * array large enough to handle the above mentioned case.  The constant
312  * NUM_STRINGS defines the number of strings in this array:  we can tolerate
313  * up to NUM_STRINGS calls before we start overwriting old information.
314  * Keeping NUM_STRINGS a power of two will allow an intelligent optimizer
315  * to convert the modulo operation into something quicker.  What a hack!
316  */
317 
318 #define NUM_STRINGS 8
319 
320 char *
321 format_k(int amt)
322 {
323 	static char retarray[NUM_STRINGS][16];
324 	static int  idx = 0;
325 	char *ret, tag = 'K';
326 
327 	ret = retarray[idx];
328 	idx = (idx + 1) % NUM_STRINGS;
329 
330 	if (amt >= 10000) {
331 		amt = (amt + 512) / 1024;
332 		tag = 'M';
333 		if (amt >= 10000) {
334 			amt = (amt + 512) / 1024;
335 			tag = 'G';
336 		}
337 	}
338 	snprintf(ret, sizeof(retarray[0]), "%d%c", amt, tag);
339 	return (ret);
340 }
341 
342 int
343 find_pid(pid_t pid)
344 {
345 	struct kinfo_proc *pbase, *cur;
346 	int nproc;
347 
348 	if ((pbase = getprocs(KERN_PROC_KTHREAD, 0, &nproc)) == NULL)
349 		quit(23);
350 
351 	for (cur = pbase; cur < &pbase[nproc]; cur++)
352 		if (cur->p_pid == pid)
353 			return 1;
354 	return 0;
355 }
356