xref: /NextBSD/contrib/top/commands.c (revision 95f7c2f56c7268d6ed9c2a56d357aeeac260363b)
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 the routines that implement some of the interactive
16  *  mode commands.  Note that some of the commands are implemented in-line
17  *  in "main".  This is necessary because they change the global state of
18  *  "top" (i.e.:  changing the number of processes to display).
19  */
20 
21 #include "os.h"
22 #include <ctype.h>
23 #include <signal.h>
24 #include <errno.h>
25 #include <sys/time.h>
26 #include <sys/resource.h>
27 
28 #include "sigdesc.h"		/* generated automatically */
29 #include "top.h"
30 #include "boolean.h"
31 #include "utils.h"
32 
33 extern int  errno;
34 
35 extern char *copyright;
36 
37 /* imported from screen.c */
38 extern int overstrike;
39 
40 int err_compar();
41 char *err_string();
42 
43 /*
44  *  show_help() - display the help screen; invoked in response to
45  *		either 'h' or '?'.
46  */
47 
show_help()48 show_help()
49 
50 {
51     printf("Top version %s, %s\n", version_string(), copyright);
52     fputs("\n\n\
53 A top users display for Unix\n\
54 \n\
55 These single-character commands are available:\n\
56 \n\
57 ^L      - redraw screen\n\
58 q       - quit\n\
59 h or ?  - help; show this text\n", stdout);
60 
61     /* not all commands are availalbe with overstrike terminals */
62     if (overstrike)
63     {
64 	fputs("\n\
65 Other commands are also available, but this terminal is not\n\
66 sophisticated enough to handle those commands gracefully.\n\n", stdout);
67     }
68     else
69     {
70 	fputs("\
71 C       - toggle the displaying of weighted CPU percentage\n\
72 d       - change number of displays to show\n\
73 e       - list errors generated by last \"kill\" or \"renice\" command\n\
74 H       - toggle the displaying of threads\n\
75 i or I  - toggle the displaying of idle processes\n\
76 j       - toggle the displaying of jail ID\n\
77 J       - display processes for only one jail (+ selects all jails)\n\
78 k       - kill processes; send a signal to a list of processes\n\
79 m       - toggle the display between 'cpu' and 'io' modes\n\
80 n or #  - change number of processes to display\n", stdout);
81 #ifdef ORDER
82 	if (displaymode == DISP_CPU)
83 		fputs("\
84 o       - specify sort order (pri, size, res, cpu, time, threads, jid, pid)\n",
85 	    stdout);
86 	else
87 		fputs("\
88 o       - specify sort order (vcsw, ivcsw, read, write, fault, total, jid, pid)\n",
89 	    stdout);
90 #endif
91 	fputs("\
92 P       - toggle the displaying of per-CPU statistics\n\
93 r       - renice a process\n\
94 s       - change number of seconds to delay between updates\n\
95 S       - toggle the displaying of system processes\n\
96 a       - toggle the displaying of process titles\n\
97 t       - toggle the display of this process\n\
98 u       - display processes for only one user (+ selects all users)\n\
99 z       - toggle the displaying of the system idle process\n\
100 \n\
101 \n", stdout);
102     }
103 }
104 
105 /*
106  *  Utility routines that help with some of the commands.
107  */
108 
next_field(str)109 char *next_field(str)
110 
111 register char *str;
112 
113 {
114     if ((str = strchr(str, ' ')) == NULL)
115     {
116 	return(NULL);
117     }
118     *str = '\0';
119     while (*++str == ' ') /* loop */;
120 
121     /* if there is nothing left of the string, return NULL */
122     /* This fix is dedicated to Greg Earle */
123     return(*str == '\0' ? NULL : str);
124 }
125 
scanint(str,intp)126 scanint(str, intp)
127 
128 char *str;
129 int  *intp;
130 
131 {
132     register int val = 0;
133     register char ch;
134 
135     /* if there is nothing left of the string, flag it as an error */
136     /* This fix is dedicated to Greg Earle */
137     if (*str == '\0')
138     {
139 	return(-1);
140     }
141 
142     while ((ch = *str++) != '\0')
143     {
144 	if (isdigit(ch))
145 	{
146 	    val = val * 10 + (ch - '0');
147 	}
148 	else if (isspace(ch))
149 	{
150 	    break;
151 	}
152 	else
153 	{
154 	    return(-1);
155 	}
156     }
157     *intp = val;
158     return(0);
159 }
160 
161 /*
162  *  Some of the commands make system calls that could generate errors.
163  *  These errors are collected up in an array of structures for later
164  *  contemplation and display.  Such routines return a string containing an
165  *  error message, or NULL if no errors occurred.  The next few routines are
166  *  for manipulating and displaying these errors.  We need an upper limit on
167  *  the number of errors, so we arbitrarily choose 20.
168  */
169 
170 #define ERRMAX 20
171 
172 struct errs		/* structure for a system-call error */
173 {
174     int  errnum;	/* value of errno (that is, the actual error) */
175     char *arg;		/* argument that caused the error */
176 };
177 
178 static struct errs errs[ERRMAX];
179 static int errcnt;
180 static char *err_toomany = " too many errors occurred";
181 static char *err_listem =
182 	" Many errors occurred.  Press `e' to display the list of errors.";
183 
184 /* These macros get used to reset and log the errors */
185 #define ERR_RESET   errcnt = 0
186 #define ERROR(p, e) if (errcnt >= ERRMAX) \
187 		    { \
188 			return(err_toomany); \
189 		    } \
190 		    else \
191 		    { \
192 			errs[errcnt].arg = (p); \
193 			errs[errcnt++].errnum = (e); \
194 		    }
195 
196 /*
197  *  err_string() - return an appropriate error string.  This is what the
198  *	command will return for displaying.  If no errors were logged, then
199  *	return NULL.  The maximum length of the error string is defined by
200  *	"STRMAX".
201  */
202 
203 #define STRMAX 80
204 
err_string()205 char *err_string()
206 
207 {
208     register struct errs *errp;
209     register int  cnt = 0;
210     register int  first = Yes;
211     register int  currerr = -1;
212     int stringlen;		/* characters still available in "string" */
213     static char string[STRMAX];
214 
215     /* if there are no errors, return NULL */
216     if (errcnt == 0)
217     {
218 	return(NULL);
219     }
220 
221     /* sort the errors */
222     qsort((char *)errs, errcnt, sizeof(struct errs), err_compar);
223 
224     /* need a space at the front of the error string */
225     string[0] = ' ';
226     string[1] = '\0';
227     stringlen = STRMAX - 2;
228 
229     /* loop thru the sorted list, building an error string */
230     while (cnt < errcnt)
231     {
232 	errp = &(errs[cnt++]);
233 	if (errp->errnum != currerr)
234 	{
235 	    if (currerr != -1)
236 	    {
237 		if ((stringlen = str_adderr(string, stringlen, currerr)) < 2)
238 		{
239 		    return(err_listem);
240 		}
241 		(void) strcat(string, "; ");	  /* we know there's more */
242 	    }
243 	    currerr = errp->errnum;
244 	    first = Yes;
245 	}
246 	if ((stringlen = str_addarg(string, stringlen, errp->arg, first)) ==0)
247 	{
248 	    return(err_listem);
249 	}
250 	first = No;
251     }
252 
253     /* add final message */
254     stringlen = str_adderr(string, stringlen, currerr);
255 
256     /* return the error string */
257     return(stringlen == 0 ? err_listem : string);
258 }
259 
260 /*
261  *  str_adderr(str, len, err) - add an explanation of error "err" to
262  *	the string "str".
263  */
264 
str_adderr(str,len,err)265 str_adderr(str, len, err)
266 
267 char *str;
268 int len;
269 int err;
270 
271 {
272     register char *msg;
273     register int  msglen;
274 
275     msg = err == 0 ? "Not a number" : errmsg(err);
276     msglen = strlen(msg) + 2;
277     if (len <= msglen)
278     {
279 	return(0);
280     }
281     (void) strcat(str, ": ");
282     (void) strcat(str, msg);
283     return(len - msglen);
284 }
285 
286 /*
287  *  str_addarg(str, len, arg, first) - add the string argument "arg" to
288  *	the string "str".  This is the first in the group when "first"
289  *	is set (indicating that a comma should NOT be added to the front).
290  */
291 
str_addarg(str,len,arg,first)292 str_addarg(str, len, arg, first)
293 
294 char *str;
295 int  len;
296 char *arg;
297 int  first;
298 
299 {
300     register int arglen;
301 
302     arglen = strlen(arg);
303     if (!first)
304     {
305 	arglen += 2;
306     }
307     if (len <= arglen)
308     {
309 	return(0);
310     }
311     if (!first)
312     {
313 	(void) strcat(str, ", ");
314     }
315     (void) strcat(str, arg);
316     return(len - arglen);
317 }
318 
319 /*
320  *  err_compar(p1, p2) - comparison routine used by "qsort"
321  *	for sorting errors.
322  */
323 
err_compar(p1,p2)324 err_compar(p1, p2)
325 
326 register struct errs *p1, *p2;
327 
328 {
329     register int result;
330 
331     if ((result = p1->errnum - p2->errnum) == 0)
332     {
333 	return(strcmp(p1->arg, p2->arg));
334     }
335     return(result);
336 }
337 
338 /*
339  *  error_count() - return the number of errors currently logged.
340  */
341 
error_count()342 error_count()
343 
344 {
345     return(errcnt);
346 }
347 
348 /*
349  *  show_errors() - display on stdout the current log of errors.
350  */
351 
show_errors()352 show_errors()
353 
354 {
355     register int cnt = 0;
356     register struct errs *errp = errs;
357 
358     printf("%d error%s:\n\n", errcnt, errcnt == 1 ? "" : "s");
359     while (cnt++ < errcnt)
360     {
361 	printf("%5s: %s\n", errp->arg,
362 	    errp->errnum == 0 ? "Not a number" : errmsg(errp->errnum));
363 	errp++;
364     }
365 }
366 
367 /*
368  *  kill_procs(str) - send signals to processes, much like the "kill"
369  *		command does; invoked in response to 'k'.
370  */
371 
kill_procs(str)372 char *kill_procs(str)
373 
374 char *str;
375 
376 {
377     register char *nptr;
378     int signum = SIGTERM;	/* default */
379     int procnum;
380     struct sigdesc *sigp;
381     int uid;
382 
383     /* reset error array */
384     ERR_RESET;
385 
386     /* remember our uid */
387     uid = getuid();
388 
389     /* skip over leading white space */
390     while (isspace(*str)) str++;
391 
392     if (str[0] == '-')
393     {
394 	/* explicit signal specified */
395 	if ((nptr = next_field(str)) == NULL)
396 	{
397 	    return(" kill: no processes specified");
398 	}
399 
400 	if (isdigit(str[1]))
401 	{
402 	    (void) scanint(str + 1, &signum);
403 	    if (signum <= 0 || signum >= NSIG)
404 	    {
405 		return(" invalid signal number");
406 	    }
407 	}
408 	else
409 	{
410 	    /* translate the name into a number */
411 	    for (sigp = sigdesc; sigp->name != NULL; sigp++)
412 	    {
413 		if (strcmp(sigp->name, str + 1) == 0)
414 		{
415 		    signum = sigp->number;
416 		    break;
417 		}
418 	    }
419 
420 	    /* was it ever found */
421 	    if (sigp->name == NULL)
422 	    {
423 		return(" bad signal name");
424 	    }
425 	}
426 	/* put the new pointer in place */
427 	str = nptr;
428     }
429 
430     /* loop thru the string, killing processes */
431     do
432     {
433 	if (scanint(str, &procnum) == -1)
434 	{
435 	    ERROR(str, 0);
436 	}
437 	else
438 	{
439 	    /* check process owner if we're not root */
440 	    if (uid && (uid != proc_owner(procnum)))
441 	    {
442 		ERROR(str, EACCES);
443 	    }
444 	    /* go in for the kill */
445 	    else if (kill(procnum, signum) == -1)
446 	    {
447 		/* chalk up an error */
448 		ERROR(str, errno);
449 	    }
450 	}
451     } while ((str = next_field(str)) != NULL);
452 
453     /* return appropriate error string */
454     return(err_string());
455 }
456 
457 /*
458  *  renice_procs(str) - change the "nice" of processes, much like the
459  *		"renice" command does; invoked in response to 'r'.
460  */
461 
renice_procs(str)462 char *renice_procs(str)
463 
464 char *str;
465 
466 {
467     register char negate;
468     int prio;
469     int procnum;
470     int uid;
471 
472     ERR_RESET;
473     uid = getuid();
474 
475     /* allow for negative priority values */
476     if ((negate = (*str == '-')) != 0)
477     {
478 	/* move past the minus sign */
479 	str++;
480     }
481 
482     /* use procnum as a temporary holding place and get the number */
483     procnum = scanint(str, &prio);
484 
485     /* negate if necessary */
486     if (negate)
487     {
488 	prio = -prio;
489     }
490 
491 #if defined(PRIO_MIN) && defined(PRIO_MAX)
492     /* check for validity */
493     if (procnum == -1 || prio < PRIO_MIN || prio > PRIO_MAX)
494     {
495 	return(" bad priority value");
496     }
497 #endif
498 
499     /* move to the first process number */
500     if ((str = next_field(str)) == NULL)
501     {
502 	return(" no processes specified");
503     }
504 
505     /* loop thru the process numbers, renicing each one */
506     do
507     {
508 	if (scanint(str, &procnum) == -1)
509 	{
510 	    ERROR(str, 0);
511 	}
512 
513 	/* check process owner if we're not root */
514 	else if (uid && (uid != proc_owner(procnum)))
515 	{
516 	    ERROR(str, EACCES);
517 	}
518 	else if (setpriority(PRIO_PROCESS, procnum, prio) == -1)
519 	{
520 	    ERROR(str, errno);
521 	}
522     } while ((str = next_field(str)) != NULL);
523 
524     /* return appropriate error string */
525     return(err_string());
526 }
527 
528