xref: /freebsd/usr.bin/top/utils.c (revision 2da0fcde21e0b90384f61fd50b87ea7dbd820233)
1 /*
2  *  This program may be freely redistributed,
3  *  but this entire comment MUST remain intact.
4  *
5  *  Copyright (c) 2018, Daichi Goto
6  *  Copyright (c) 2018, Eitan Adler
7  *  Copyright (c) 1984, 1989, William LeFebvre, Rice University
8  *  Copyright (c) 1989, 1990, 1992, William LeFebvre, Northwestern University
9  *
10  * $FreeBSD$
11  */
12 
13 /*
14  *  This file contains various handy utilities used by top.
15  */
16 
17 #include "top.h"
18 #include "utils.h"
19 
20 #include <sys/param.h>
21 #include <sys/sysctl.h>
22 #include <sys/user.h>
23 
24 #include <libutil.h>
25 #include <stdlib.h>
26 #include <stdio.h>
27 #include <string.h>
28 #include <fcntl.h>
29 #include <paths.h>
30 #include <kvm.h>
31 
32 int
33 atoiwi(const char *str)
34 {
35     size_t len;
36 
37     len = strlen(str);
38     if (len != 0)
39     {
40 	if (strncmp(str, "infinity", len) == 0 ||
41 	    strncmp(str, "all",      len) == 0 ||
42 	    strncmp(str, "maximum",  len) == 0)
43 	{
44 	    return(Infinity);
45 	}
46 	else if (str[0] == '-')
47 	{
48 	    return(Invalid);
49 	}
50 	else
51 	{
52 		return((int)strtol(str, NULL, 10));
53 	}
54     }
55     return(0);
56 }
57 
58 /*
59  *  itoa - convert integer (decimal) to ascii string for positive numbers
60  *  	   only (we don't bother with negative numbers since we know we
61  *	   don't use them).
62  */
63 
64 				/*
65 				 * How do we know that 16 will suffice?
66 				 * Because the biggest number that we will
67 				 * ever convert will be 2^32-1, which is 10
68 				 * digits.
69 				 */
70 _Static_assert(sizeof(int) <= 4, "buffer too small for this sized int");
71 
72 char *
73 itoa(unsigned int val)
74 {
75     static char buffer[16];	/* result is built here */
76     				/* 16 is sufficient since the largest number
77 				   we will ever convert will be 2^32-1,
78 				   which is 10 digits. */
79 
80 	sprintf(buffer, "%u", val);
81     return (buffer);
82 }
83 
84 /*
85  *  itoa7(val) - like itoa, except the number is right justified in a 7
86  *	character field.  This code is a duplication of itoa instead of
87  *	a front end to a more general routine for efficiency.
88  */
89 
90 char *
91 itoa7(int val)
92 {
93     static char buffer[16];	/* result is built here */
94     				/* 16 is sufficient since the largest number
95 				   we will ever convert will be 2^32-1,
96 				   which is 10 digits. */
97 
98 	sprintf(buffer, "%6u", val);
99     return (buffer);
100 }
101 
102 /*
103  *  digits(val) - return number of decimal digits in val.  Only works for
104  *	non-negative numbers.
105  */
106 
107 int __pure2
108 digits(int val)
109 {
110     int cnt = 0;
111 	if (val == 0) {
112 		return 1;
113 	}
114 
115     while (val > 0) {
116 		cnt++;
117 		val /= 10;
118     }
119     return(cnt);
120 }
121 
122 /*
123  * string_index(string, array) - find string in array and return index
124  */
125 
126 int
127 string_index(const char *string, const char * const *array)
128 {
129     size_t i = 0;
130 
131     while (*array != NULL)
132     {
133 	if (strcmp(string, *array) == 0)
134 	{
135 	    return(i);
136 	}
137 	array++;
138 	i++;
139     }
140     return(-1);
141 }
142 
143 /*
144  * argparse(line, cntp) - parse arguments in string "line", separating them
145  *	out into an argv-like array, and setting *cntp to the number of
146  *	arguments encountered.  This is a simple parser that doesn't understand
147  *	squat about quotes.
148  */
149 
150 const char * const *
151 argparse(char *line, int *cntp)
152 {
153     const char **ap;
154     static const char *argv[1024] = {0};
155 
156     *cntp = 1;
157     ap = &argv[1];
158     while ((*ap = strsep(&line, " ")) != NULL) {
159         if (**ap != '\0') {
160             (*cntp)++;
161             if (*cntp >= (int)nitems(argv)) {
162                 break;
163             }
164 	    ap++;
165         }
166     }
167     return (argv);
168 }
169 
170 /*
171  *  percentages(cnt, out, new, old, diffs) - calculate percentage change
172  *	between array "old" and "new", putting the percentages i "out".
173  *	"cnt" is size of each array and "diffs" is used for scratch space.
174  *	The array "old" is updated on each call.
175  *	The routine assumes modulo arithmetic.  This function is especially
176  *	useful on for calculating cpu state percentages.
177  */
178 
179 long
180 percentages(int cnt, int *out, long *new, long *old, long *diffs)
181 {
182     int i;
183     long change;
184     long total_change;
185     long *dp;
186     long half_total;
187 
188     /* initialization */
189     total_change = 0;
190     dp = diffs;
191 
192     /* calculate changes for each state and the overall change */
193     for (i = 0; i < cnt; i++)
194     {
195 	if ((change = *new - *old) < 0)
196 	{
197 	    /* this only happens when the counter wraps */
198 	    change = (int)
199 		((unsigned long)*new-(unsigned long)*old);
200 	}
201 	total_change += (*dp++ = change);
202 	*old++ = *new++;
203     }
204 
205     /* avoid divide by zero potential */
206     if (total_change == 0)
207     {
208 	total_change = 1;
209     }
210 
211     /* calculate percentages based on overall change, rounding up */
212     half_total = total_change / 2l;
213 
214 	for (i = 0; i < cnt; i++)
215 	{
216 		*out++ = (int)((*diffs++ * 1000 + half_total) / total_change);
217 	}
218 
219     /* return the total in case the caller wants to use it */
220     return(total_change);
221 }
222 
223 /* format_time(seconds) - format number of seconds into a suitable
224  *		display that will fit within 6 characters.  Note that this
225  *		routine builds its string in a static area.  If it needs
226  *		to be called more than once without overwriting previous data,
227  *		then we will need to adopt a technique similar to the
228  *		one used for format_k.
229  */
230 
231 /* Explanation:
232    We want to keep the output within 6 characters.  For low values we use
233    the format mm:ss.  For values that exceed 999:59, we switch to a format
234    that displays hours and fractions:  hhh.tH.  For values that exceed
235    999.9, we use hhhh.t and drop the "H" designator.  For values that
236    exceed 9999.9, we use "???".
237  */
238 
239 const char *
240 format_time(long seconds)
241 {
242 	static char result[10];
243 
244 	/* sanity protection */
245 	if (seconds < 0 || seconds > (99999l * 360l))
246 	{
247 		strcpy(result, "   ???");
248 	}
249 	else if (seconds >= (1000l * 60l))
250 	{
251 		/* alternate (slow) method displaying hours and tenths */
252 		sprintf(result, "%5.1fH", (double)seconds / (double)(60l * 60l));
253 
254 		/* It is possible that the sprintf took more than 6 characters.
255 		   If so, then the "H" appears as result[6].  If not, then there
256 		   is a \0 in result[6].  Either way, it is safe to step on.
257 		   */
258 		result[6] = '\0';
259 	}
260 	else
261 	{
262 		/* standard method produces MMM:SS */
263 		sprintf(result, "%3ld:%02ld",
264 				seconds / 60l, seconds % 60l);
265 	}
266 	return(result);
267 }
268 
269 /*
270  * format_k(amt) - format a kilobyte memory value, returning a string
271  *		suitable for display.  Returns a pointer to a static
272  *		area that changes each call.  "amt" is converted to a fixed
273  *		size humanize_number call
274  */
275 
276 /*
277  * Compromise time.  We need to return a string, but we don't want the
278  * caller to have to worry about freeing a dynamically allocated string.
279  * Unfortunately, we can't just return a pointer to a static area as one
280  * of the common uses of this function is in a large call to sprintf where
281  * it might get invoked several times.  Our compromise is to maintain an
282  * array of strings and cycle thru them with each invocation.  We make the
283  * array large enough to handle the above mentioned case.  The constant
284  * NUM_STRINGS defines the number of strings in this array:  we can tolerate
285  * up to NUM_STRINGS calls before we start overwriting old information.
286  * Keeping NUM_STRINGS a power of two will allow an intelligent optimizer
287  * to convert the modulo operation into something quicker.  What a hack!
288  */
289 
290 #define NUM_STRINGS 8
291 
292 char *
293 format_k(int64_t amt)
294 {
295     static char retarray[NUM_STRINGS][16];
296     static int index = 0;
297     char *ret;
298 
299     ret = retarray[index];
300 	index = (index + 1) % NUM_STRINGS;
301 	humanize_number(ret, 5, amt * 1024, "", HN_AUTOSCALE, HN_NOSPACE);
302 	return (ret);
303 }
304 
305 int
306 find_pid(pid_t pid)
307 {
308 	kvm_t *kd = NULL;
309 	struct kinfo_proc *pbase = NULL;
310 	int nproc;
311 	int ret = 0;
312 
313 	kd = kvm_open(NULL, _PATH_DEVNULL, NULL, O_RDONLY, NULL);
314 	if (kd == NULL) {
315 		fprintf(stderr, "top: kvm_open() failed.\n");
316 		quit(TOP_EX_SYS_ERROR);
317 	}
318 
319 	pbase = kvm_getprocs(kd, KERN_PROC_PID, pid, &nproc);
320 	if (pbase == NULL) {
321 		goto done;
322 	}
323 
324 	if ((nproc == 1) && (pbase->ki_pid == pid)) {
325 		ret = 1;
326 	}
327 
328 done:
329 	kvm_close(kd);
330 	return ret;
331 }
332 
333 /*
334  * utf8strvisx(dst,src,src_len)
335  *	strvisx(dst,src,src_len,VIS_NL|VIS_CSTYLE) coresponding to UTF-8.
336  */
337 static const char *vis_encodes[] = {
338 	"\\0", "\\^A", "\\^B", "\\^C", "\\^D", "\\^E", "\\^F", "\\a",
339 	"\\b", "\t", "\\n", "\\v", "\\f", "\\r", "\\^N", "\\^O", "\\^P",
340 	"\\^Q", "\\^R", "\\^S", "\\^T", "\\^U", "\\^V", "\\^W", "\\^X",
341 	"\\^Y", "\\^Z", "\\^[", "\\^\\", "\\^]", "\\^^", "\\^_"
342 };
343 
344 int
345 utf8strvisx(char *dst, const char *src, size_t src_len)
346 {
347 	const char *src_p;
348 	char *dst_p;
349 	int i, j, olen, len;
350 
351 	src_p = src;
352 	dst_p = dst;
353 	i = olen = 0;
354 	len = (int)src_len;
355 	while (i < len) {
356 		if (0x00 == (0x80 & *src_p)) {
357 			if (0 <= *src_p && *src_p <= 31) {
358 				j = strlen(vis_encodes[(int)*src_p]);
359 				strcpy(dst_p, vis_encodes[(int)*src_p]);
360 				dst_p += j;
361 				olen += j;
362 			} else if (127 == *src_p) {
363 				strcpy(dst_p, "\\^?");
364 				olen += 3;
365 			} else {
366 				*dst_p++ = *src_p;
367 				++olen;
368 			}
369 			++i;
370 			++src_p;
371 		} else if (0xC0 == (0xE0 & *src_p)) {
372 			*dst_p++ = *src_p++; ++i; ++olen;
373 			if (i < len) { *dst_p++ = *src_p++; ++i; ++olen; }
374 		} else if (0xE0 == (0xF0 & *src_p)) {
375 			*dst_p++ = *src_p++; ++i; ++olen;
376 			if (i < len) { *dst_p++ = *src_p++; ++i; ++olen; }
377 			if (i < len) { *dst_p++ = *src_p++; ++i; ++olen; }
378 		} else if (0xF0 == (0xF8 & *src_p)) {
379 			*dst_p++ = *src_p++; ++i; ++olen;
380 			if (i < len) { *dst_p++ = *src_p++; ++i; ++olen; }
381 			if (i < len) { *dst_p++ = *src_p++; ++i; ++olen; }
382 			if (i < len) { *dst_p++ = *src_p++; ++i; ++olen; }
383 		} else {
384 			*dst_p++ = '?'; ++i; ++olen;
385 		}
386 	}
387 
388 	return olen;
389 }
390