xref: /openbsd-src/usr.bin/top/utils.c (revision 0eea0d082377cb9c3ec583313dc4d52b7b6a4d6d)
1 /* $OpenBSD: utils.c,v 1.13 2003/07/07 21:36:52 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 <stdio.h>
37 #include <string.h>
38 #include <stdlib.h>
39 #include <unistd.h>
40 
41 #include "top.h"
42 #include "utils.h"
43 
44 int
45 atoiwi(char *str)
46 {
47 	size_t len;
48 
49 	len = strlen(str);
50 	if (len != 0) {
51 		if (strncmp(str, "infinity", len) == 0 ||
52 		    strncmp(str, "all", len) == 0 ||
53 		    strncmp(str, "maximum", len) == 0) {
54 			return (Infinity);
55 		} else if (str[0] == '-')
56 			return (Invalid);
57 		else
58 			return (atoi(str));
59 	}
60 	return (0);
61 }
62 
63 /*
64  * itoa - convert integer (decimal) to ascii string.
65  */
66 char *
67 itoa(int val)
68 {
69 	static char buffer[16];	/* result is built here */
70 
71 	/*
72 	 * 16 is sufficient since the largest number we will ever convert
73 	 * will be 2^32-1, which is 10 digits.
74 	 */
75 	(void)snprintf(buffer, sizeof(buffer), "%d", val);
76 	return (buffer);
77 }
78 
79 /*
80  * format_uid(uid) - like itoa, except for uid_t and the number is right
81  * justified in a 6 character field to match uname_field in top.c.
82  */
83 char *
84 format_uid(uid_t uid)
85 {
86 	static char buffer[16];	/* result is built here */
87 
88 	/*
89 	 * 16 is sufficient since the largest uid we will ever convert
90 	 * will be 2^32-1, which is 10 digits.
91 	 */
92 	(void)snprintf(buffer, sizeof(buffer), "%6u", uid);
93 	return (buffer);
94 }
95 
96 /*
97  * digits(val) - return number of decimal digits in val.  Only works for
98  * positive numbers.  If val <= 0 then digits(val) == 0.
99  */
100 int
101 digits(int val)
102 {
103 	int cnt = 0;
104 
105 	while (val > 0) {
106 		cnt++;
107 		val /= 10;
108 	}
109 	return (cnt);
110 }
111 
112 /*
113  * string_index(string, array) - find string in array and return index
114  */
115 int
116 string_index(char *string, char **array)
117 {
118 	int i = 0;
119 
120 	while (*array != NULL) {
121 		if (strcmp(string, *array) == 0)
122 			return (i);
123 		array++;
124 		i++;
125 	}
126 	return (-1);
127 }
128 
129 /*
130  * argparse(line, cntp) - parse arguments in string "line", separating them
131  * out into an argv-like array, and setting *cntp to the number of
132  * arguments encountered.  This is a simple parser that doesn't understand
133  * squat about quotes.
134  */
135 char **
136 argparse(char *line, int *cntp)
137 {
138 	char **argv, **argarray, *args, *from, *to;
139 	int cnt, ch, length, lastch;
140 
141 	/*
142 	 * unfortunately, the only real way to do this is to go thru the
143 	 * input string twice.
144 	 */
145 
146 	/* step thru the string counting the white space sections */
147 	from = line;
148 	lastch = cnt = length = 0;
149 	while ((ch = *from++) != '\0') {
150 		length++;
151 		if (ch == ' ' && lastch != ' ')
152 			cnt++;
153 		lastch = ch;
154 	}
155 
156 	/*
157 	 * add three to the count:  one for the initial "dummy" argument, one
158 	 * for the last argument and one for NULL
159 	 */
160 	cnt += 3;
161 
162 	/* allocate a char * array to hold the pointers */
163 	argarray = (char **) malloc(cnt * sizeof(char *));
164 
165 	/* allocate another array to hold the strings themselves */
166 	args = (char *) malloc(length + 2);
167 
168 	/* initialization for main loop */
169 	from = line;
170 	to = args;
171 	argv = argarray;
172 	lastch = '\0';
173 
174 	/* create a dummy argument to keep getopt happy */
175 	*argv++ = to;
176 	*to++ = '\0';
177 	cnt = 2;
178 
179 	/* now build argv while copying characters */
180 	*argv++ = to;
181 	while ((ch = *from++) != '\0') {
182 		if (ch != ' ') {
183 			if (lastch == ' ') {
184 				*to++ = '\0';
185 				*argv++ = to;
186 				cnt++;
187 			}
188 			*to++ = ch;
189 		}
190 		lastch = ch;
191 	}
192 	*to++ = '\0';
193 
194 	/* set cntp and return the allocated array */
195 	*cntp = cnt;
196 	return (argarray);
197 }
198 
199 /*
200  * percentages(cnt, out, new, old, diffs) - calculate percentage change
201  * between array "old" and "new", putting the percentages i "out".
202  * "cnt" is size of each array and "diffs" is used for scratch space.
203  * The array "old" is updated on each call.
204  * The routine assumes modulo arithmetic.  This function is especially
205  * useful on BSD mchines for calculating cpu state percentages.
206  */
207 int
208 percentages(int cnt, int *out, long *new, long *old, long *diffs)
209 {
210 	long change, total_change, *dp, half_total;
211 	int i;
212 
213 	/* initialization */
214 	total_change = 0;
215 	dp = diffs;
216 
217 	/* calculate changes for each state and the overall change */
218 	for (i = 0; i < cnt; i++) {
219 		if ((change = *new - *old) < 0) {
220 			/* this only happens when the counter wraps */
221 			change = ((unsigned int)*new - (unsigned int)*old);
222 		}
223 		total_change += (*dp++ = change);
224 		*old++ = *new++;
225 	}
226 
227 	/* avoid divide by zero potential */
228 	if (total_change == 0)
229 		total_change = 1;
230 
231 	/* calculate percentages based on overall change, rounding up */
232 	half_total = total_change / 2l;
233 	for (i = 0; i < cnt; i++)
234 		*out++ = ((*diffs++ * 1000 + half_total) / total_change);
235 
236 	/* return the total in case the caller wants to use it */
237 	return (total_change);
238 }
239 
240 /*
241  * format_time(seconds) - format number of seconds into a suitable display
242  * that will fit within 6 characters.  Note that this routine builds its
243  * string in a static area.  If it needs to be called more than once without
244  * overwriting previous data, then we will need to adopt a technique similar
245  * to the one used for format_k.
246  */
247 
248 /*
249  * Explanation: We want to keep the output within 6 characters.  For low
250  * values we use the format mm:ss.  For values that exceed 999:59, we switch
251  * to a format that displays hours and fractions:  hhh.tH.  For values that
252  * exceed 999.9, we use hhhh.t and drop the "H" designator.  For values that
253  * exceed 9999.9, we use "???".
254  */
255 
256 char *
257 format_time(time_t seconds)
258 {
259 	static char result[10];
260 
261 	/* sanity protection */
262 	if (seconds < 0 || seconds > (99999l * 360l)) {
263 		strlcpy(result, "   ???", sizeof result);
264 	} else if (seconds >= (1000l * 60l)) {
265 		/* alternate (slow) method displaying hours and tenths */
266 		snprintf(result, sizeof(result), "%5.1fH",
267 		    (double) seconds / (double) (60l * 60l));
268 
269 		/*
270 		 * It is possible that the snprintf took more than 6
271 		 * characters. If so, then the "H" appears as result[6].  If
272 		 * not, then there is a \0 in result[6].  Either way, it is
273 		 * safe to step on.
274 		 */
275 		result[6] = '\0';
276 	} else {
277 		/* standard method produces MMM:SS */
278 		/* we avoid printf as must as possible to make this quick */
279 		snprintf(result, sizeof(result), "%3d:%02d", seconds / 60,
280 		    seconds % 60);
281 	}
282 	return (result);
283 }
284 
285 /*
286  * format_k(amt) - format a kilobyte memory value, returning a string
287  * suitable for display.  Returns a pointer to a static
288  * area that changes each call.  "amt" is converted to a
289  * string with a trailing "K".  If "amt" is 10000 or greater,
290  * then it is formatted as megabytes (rounded) with a
291  * trailing "M".
292  */
293 
294 /*
295  * Compromise time.  We need to return a string, but we don't want the
296  * caller to have to worry about freeing a dynamically allocated string.
297  * Unfortunately, we can't just return a pointer to a static area as one
298  * of the common uses of this function is in a large call to snprintf where
299  * it might get invoked several times.  Our compromise is to maintain an
300  * array of strings and cycle thru them with each invocation.  We make the
301  * array large enough to handle the above mentioned case.  The constant
302  * NUM_STRINGS defines the number of strings in this array:  we can tolerate
303  * up to NUM_STRINGS calls before we start overwriting old information.
304  * Keeping NUM_STRINGS a power of two will allow an intelligent optimizer
305  * to convert the modulo operation into something quicker.  What a hack!
306  */
307 
308 #define NUM_STRINGS 8
309 
310 char *
311 format_k(int amt)
312 {
313 	static char retarray[NUM_STRINGS][16];
314 	static int  idx = 0;
315 	char *ret, tag = 'K';
316 
317 	ret = retarray[idx];
318 	idx = (idx + 1) % NUM_STRINGS;
319 
320 	if (amt >= 10000) {
321 		amt = (amt + 512) / 1024;
322 		tag = 'M';
323 		if (amt >= 10000) {
324 			amt = (amt + 512) / 1024;
325 			tag = 'G';
326 		}
327 	}
328 	snprintf(ret, sizeof(retarray[0]), "%d%c", amt, tag);
329 	return (ret);
330 }
331