xref: /freebsd-11-stable/contrib/top/utils.c (revision 98e0ffaefb0f241cda3a72395d3be04192ae0d47)
1 /*
2  *  Top users/processes display for Unix
3  *  Version 3
4  *
5  *  This program may be freely redistributed,
6  *  but this entire comment MUST remain intact.
7  *
8  *  Copyright (c) 1984, 1989, William LeFebvre, Rice University
9  *  Copyright (c) 1989, 1990, 1992, William LeFebvre, Northwestern University
10  *
11  * $FreeBSD$
12  */
13 
14 /*
15  *  This file contains various handy utilities used by top.
16  */
17 
18 #include "top.h"
19 #include "os.h"
20 
atoiwi(str)21 int atoiwi(str)
22 
23 char *str;
24 
25 {
26     register int len;
27 
28     len = strlen(str);
29     if (len != 0)
30     {
31 	if (strncmp(str, "infinity", len) == 0 ||
32 	    strncmp(str, "all",      len) == 0 ||
33 	    strncmp(str, "maximum",  len) == 0)
34 	{
35 	    return(Infinity);
36 	}
37 	else if (str[0] == '-')
38 	{
39 	    return(Invalid);
40 	}
41 	else
42 	{
43 	    return(atoi(str));
44 	}
45     }
46     return(0);
47 }
48 
49 /*
50  *  itoa - convert integer (decimal) to ascii string for positive numbers
51  *  	   only (we don't bother with negative numbers since we know we
52  *	   don't use them).
53  */
54 
55 				/*
56 				 * How do we know that 16 will suffice?
57 				 * Because the biggest number that we will
58 				 * ever convert will be 2^32-1, which is 10
59 				 * digits.
60 				 */
61 _Static_assert(sizeof(int) <= 4, "buffer too small for this sized int");
62 
itoa(val)63 char *itoa(val)
64 
65 register int val;
66 
67 {
68     register char *ptr;
69     static char buffer[16];	/* result is built here */
70     				/* 16 is sufficient since the largest number
71 				   we will ever convert will be 2^32-1,
72 				   which is 10 digits. */
73 
74     ptr = buffer + sizeof(buffer);
75     *--ptr = '\0';
76     if (val == 0)
77     {
78 	*--ptr = '0';
79     }
80     else while (val != 0)
81     {
82 	*--ptr = (val % 10) + '0';
83 	val /= 10;
84     }
85     return(ptr);
86 }
87 
88 /*
89  *  itoa7(val) - like itoa, except the number is right justified in a 7
90  *	character field.  This code is a duplication of itoa instead of
91  *	a front end to a more general routine for efficiency.
92  */
93 
itoa7(val)94 char *itoa7(val)
95 
96 register int val;
97 
98 {
99     register char *ptr;
100     static char buffer[16];	/* result is built here */
101     				/* 16 is sufficient since the largest number
102 				   we will ever convert will be 2^32-1,
103 				   which is 10 digits. */
104 
105     ptr = buffer + sizeof(buffer);
106     *--ptr = '\0';
107     if (val == 0)
108     {
109 	*--ptr = '0';
110     }
111     else while (val != 0)
112     {
113 	*--ptr = (val % 10) + '0';
114 	val /= 10;
115     }
116     while (ptr > buffer + sizeof(buffer) - 7)
117     {
118 	*--ptr = ' ';
119     }
120     return(ptr);
121 }
122 
123 /*
124  *  digits(val) - return number of decimal digits in val.  Only works for
125  *	positive numbers.  If val <= 0 then digits(val) == 0.
126  */
127 
digits(val)128 int digits(val)
129 
130 int val;
131 
132 {
133     register int cnt = 0;
134 
135     while (val > 0)
136     {
137 	cnt++;
138 	val /= 10;
139     }
140     return(cnt);
141 }
142 
143 /*
144  *  strecpy(to, from) - copy string "from" into "to" and return a pointer
145  *	to the END of the string "to".
146  */
147 
strecpy(to,from)148 char *strecpy(to, from)
149 
150 register char *to;
151 register char *from;
152 
153 {
154     while ((*to++ = *from++) != '\0');
155     return(--to);
156 }
157 
158 /*
159  * string_index(string, array) - find string in array and return index
160  */
161 
string_index(string,array)162 int string_index(string, array)
163 
164 char *string;
165 char **array;
166 
167 {
168     register int i = 0;
169 
170     while (*array != NULL)
171     {
172 	if (strcmp(string, *array) == 0)
173 	{
174 	    return(i);
175 	}
176 	array++;
177 	i++;
178     }
179     return(-1);
180 }
181 
182 /*
183  * argparse(line, cntp) - parse arguments in string "line", separating them
184  *	out into an argv-like array, and setting *cntp to the number of
185  *	arguments encountered.  This is a simple parser that doesn't understand
186  *	squat about quotes.
187  */
188 
argparse(line,cntp)189 char **argparse(line, cntp)
190 
191 char *line;
192 int *cntp;
193 
194 {
195     register char *from;
196     register char *to;
197     register int cnt;
198     register int ch;
199     int length;
200     int lastch;
201     register char **argv;
202     char **argarray;
203     char *args;
204 
205     /* unfortunately, the only real way to do this is to go thru the
206        input string twice. */
207 
208     /* step thru the string counting the white space sections */
209     from = line;
210     lastch = cnt = length = 0;
211     while ((ch = *from++) != '\0')
212     {
213 	length++;
214 	if (ch == ' ' && lastch != ' ')
215 	{
216 	    cnt++;
217 	}
218 	lastch = ch;
219     }
220 
221     /* add three to the count:  one for the initial "dummy" argument,
222        one for the last argument and one for NULL */
223     cnt += 3;
224 
225     /* allocate a char * array to hold the pointers */
226     argarray = (char **)malloc(cnt * sizeof(char *));
227 
228     /* allocate another array to hold the strings themselves */
229     args = (char *)malloc(length+2);
230 
231     /* initialization for main loop */
232     from = line;
233     to = args;
234     argv = argarray;
235     lastch = '\0';
236 
237     /* create a dummy argument to keep getopt happy */
238     *argv++ = to;
239     *to++ = '\0';
240     cnt = 2;
241 
242     /* now build argv while copying characters */
243     *argv++ = to;
244     while ((ch = *from++) != '\0')
245     {
246 	if (ch != ' ')
247 	{
248 	    if (lastch == ' ')
249 	    {
250 		*to++ = '\0';
251 		*argv++ = to;
252 		cnt++;
253 	    }
254 	    *to++ = ch;
255 	}
256 	lastch = ch;
257     }
258     *to++ = '\0';
259 
260     /* set cntp and return the allocated array */
261     *cntp = cnt;
262     return(argarray);
263 }
264 
265 /*
266  *  percentages(cnt, out, new, old, diffs) - calculate percentage change
267  *	between array "old" and "new", putting the percentages i "out".
268  *	"cnt" is size of each array and "diffs" is used for scratch space.
269  *	The array "old" is updated on each call.
270  *	The routine assumes modulo arithmetic.  This function is especially
271  *	useful on BSD mchines for calculating cpu state percentages.
272  */
273 
percentages(cnt,out,new,old,diffs)274 long percentages(cnt, out, new, old, diffs)
275 
276 int cnt;
277 int *out;
278 register long *new;
279 register long *old;
280 long *diffs;
281 
282 {
283     register int i;
284     register long change;
285     register long total_change;
286     register long *dp;
287     long half_total;
288 
289     /* initialization */
290     total_change = 0;
291     dp = diffs;
292 
293     /* calculate changes for each state and the overall change */
294     for (i = 0; i < cnt; i++)
295     {
296 	if ((change = *new - *old) < 0)
297 	{
298 	    /* this only happens when the counter wraps */
299 	    change = (int)
300 		((unsigned long)*new-(unsigned long)*old);
301 	}
302 	total_change += (*dp++ = change);
303 	*old++ = *new++;
304     }
305 
306     /* avoid divide by zero potential */
307     if (total_change == 0)
308     {
309 	total_change = 1;
310     }
311 
312     /* calculate percentages based on overall change, rounding up */
313     half_total = total_change / 2l;
314 
315     /* Do not divide by 0. Causes Floating point exception */
316     if(total_change) {
317         for (i = 0; i < cnt; i++)
318         {
319           *out++ = (int)((*diffs++ * 1000 + half_total) / total_change);
320         }
321     }
322 
323     /* return the total in case the caller wants to use it */
324     return(total_change);
325 }
326 
327 /*
328  * errmsg(errnum) - return an error message string appropriate to the
329  *           error number "errnum".  This is a substitute for the System V
330  *           function "strerror".  There appears to be no reliable way to
331  *           determine if "strerror" exists at compile time, so I make do
332  *           by providing something of similar functionality.  For those
333  *           systems that have strerror and NOT errlist, define
334  *           -DHAVE_STRERROR in the module file and this function will
335  *           use strerror.
336  */
337 
338 /* externs referenced by errmsg */
339 
340 #ifndef HAVE_STRERROR
341 #ifndef SYS_ERRLIST_DECLARED
342 #define SYS_ERRLIST_DECLARED
343 extern char *sys_errlist[];
344 #endif
345 
346 extern int sys_nerr;
347 #endif
348 
errmsg(errnum)349 char *errmsg(errnum)
350 
351 int errnum;
352 
353 {
354 #ifdef HAVE_STRERROR
355     char *msg = strerror(errnum);
356     if (msg != NULL)
357     {
358 	return msg;
359     }
360 #else
361     if (errnum > 0 && errnum < sys_nerr)
362     {
363 	return((char *)sys_errlist[errnum]);
364     }
365 #endif
366     return("No error");
367 }
368 
369 /* format_time(seconds) - format number of seconds into a suitable
370  *		display that will fit within 6 characters.  Note that this
371  *		routine builds its string in a static area.  If it needs
372  *		to be called more than once without overwriting previous data,
373  *		then we will need to adopt a technique similar to the
374  *		one used for format_k.
375  */
376 
377 /* Explanation:
378    We want to keep the output within 6 characters.  For low values we use
379    the format mm:ss.  For values that exceed 999:59, we switch to a format
380    that displays hours and fractions:  hhh.tH.  For values that exceed
381    999.9, we use hhhh.t and drop the "H" designator.  For values that
382    exceed 9999.9, we use "???".
383  */
384 
format_time(seconds)385 char *format_time(seconds)
386 
387 long seconds;
388 
389 {
390     register int value;
391     register int digit;
392     register char *ptr;
393     static char result[10];
394 
395     /* sanity protection */
396     if (seconds < 0 || seconds > (99999l * 360l))
397     {
398 	strcpy(result, "   ???");
399     }
400     else if (seconds >= (1000l * 60l))
401     {
402 	/* alternate (slow) method displaying hours and tenths */
403 	sprintf(result, "%5.1fH", (double)seconds / (double)(60l * 60l));
404 
405 	/* It is possible that the sprintf took more than 6 characters.
406 	   If so, then the "H" appears as result[6].  If not, then there
407 	   is a \0 in result[6].  Either way, it is safe to step on.
408 	 */
409 	result[6] = '\0';
410     }
411     else
412     {
413 	/* standard method produces MMM:SS */
414 	/* we avoid printf as must as possible to make this quick */
415 	sprintf(result, "%3ld:%02ld",
416 	    (long)(seconds / 60), (long)(seconds % 60));
417     }
418     return(result);
419 }
420 
421 /*
422  * format_k(amt) - format a kilobyte memory value, returning a string
423  *		suitable for display.  Returns a pointer to a static
424  *		area that changes each call.  "amt" is converted to a
425  *		string with a trailing "K".  If "amt" is 10000 or greater,
426  *		then it is formatted as megabytes (rounded) with a
427  *		trailing "M".
428  */
429 
430 /*
431  * Compromise time.  We need to return a string, but we don't want the
432  * caller to have to worry about freeing a dynamically allocated string.
433  * Unfortunately, we can't just return a pointer to a static area as one
434  * of the common uses of this function is in a large call to sprintf where
435  * it might get invoked several times.  Our compromise is to maintain an
436  * array of strings and cycle thru them with each invocation.  We make the
437  * array large enough to handle the above mentioned case.  The constant
438  * NUM_STRINGS defines the number of strings in this array:  we can tolerate
439  * up to NUM_STRINGS calls before we start overwriting old information.
440  * Keeping NUM_STRINGS a power of two will allow an intelligent optimizer
441  * to convert the modulo operation into something quicker.  What a hack!
442  */
443 
444 #define NUM_STRINGS 8
445 
format_k(amt)446 char *format_k(amt)
447 
448 int amt;
449 
450 {
451     static char retarray[NUM_STRINGS][16];
452     static int index = 0;
453     register char *p;
454     register char *ret;
455     register char tag = 'K';
456 
457     p = ret = retarray[index];
458     index = (index + 1) % NUM_STRINGS;
459 
460     if (amt >= 10000)
461     {
462 	amt = (amt + 512) / 1024;
463 	tag = 'M';
464 	if (amt >= 10000)
465 	{
466 	    amt = (amt + 512) / 1024;
467 	    tag = 'G';
468 	}
469     }
470 
471     p = strecpy(p, itoa(amt));
472     *p++ = tag;
473     *p = '\0';
474 
475     return(ret);
476 }
477 
format_k2(amt)478 char *format_k2(amt)
479 
480 unsigned long long amt;
481 
482 {
483     static char retarray[NUM_STRINGS][16];
484     static int index = 0;
485     register char *p;
486     register char *ret;
487     register char tag = 'K';
488 
489     p = ret = retarray[index];
490     index = (index + 1) % NUM_STRINGS;
491 
492     if (amt >= 100000)
493     {
494 	amt = (amt + 512) / 1024;
495 	tag = 'M';
496 	if (amt >= 100000)
497 	{
498 	    amt = (amt + 512) / 1024;
499 	    tag = 'G';
500 	}
501     }
502 
503     p = strecpy(p, itoa((int)amt));
504     *p++ = tag;
505     *p = '\0';
506 
507     return(ret);
508 }
509