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 <sys/resource.h>
22 #include <sys/signal.h>
23
24 #include <ctype.h>
25 #include <errno.h>
26 #include <signal.h>
27 #include <stdbool.h>
28 #include <stdlib.h>
29 #include <stdio.h>
30 #include <string.h>
31 #include <unistd.h>
32
33 #include "commands.h"
34 #include "top.h"
35 #include "machine.h"
36
37 static int err_compar(const void *p1, const void *p2);
38
39 struct errs /* structure for a system-call error */
40 {
41 int errnum; /* value of errno (that is, the actual error) */
42 char *arg; /* argument that caused the error */
43 };
44
45 static char *err_string(void);
46 static int str_adderr(char *str, int len, int err);
47 static int str_addarg(char *str, int len, char *arg, bool first);
48
49 /*
50 * show_help() - display the help screen; invoked in response to
51 * either 'h' or '?'.
52 */
53
54 const struct command all_commands[] =
55 {
56 {'C', "toggle the displaying of weighted CPU percentage", false, CMD_wcputog},
57 {'d', "change number of displays to show", false, CMD_displays},
58 {'e', "list errors generated by last \"kill\" or \"renice\" command", false, CMD_errors},
59 {'H', "toggle the displaying of threads", false, CMD_thrtog},
60 {'h', "show this help text", true, CMD_help},
61 {'?', NULL, true, CMD_help},
62 {'/', "filter on command name (+ selects all commands)", false, CMD_grep},
63 {'i', "toggle the displaying of idle processes", false, CMD_idletog},
64 {'I', NULL, false, CMD_idletog},
65 {'j', "toggle the displaying of jail ID", false, CMD_jidtog},
66 {'J', "display processes for only one jail (+ selects all jails)", false, CMD_jail},
67 {'k', "kill processes; send a signal to a list of processes", false, CMD_kill},
68 {'q', "quit" , true, CMD_quit},
69 {'m', "toggle the display between 'cpu' and 'io' modes", false, CMD_viewtog},
70 {'n', "change number of processes to display", false, CMD_number},
71 {'#', NULL, false, CMD_number},
72 {'o', "specify the sort order", false, CMD_order},
73 {'p', "display one process (+ selects all processes)", false, CMD_pid},
74 {'P', "toggle the displaying of per-CPU statistics", false, CMD_pcputog},
75 {'r', "renice a process", false, CMD_renice},
76 {'s', "change number of seconds to delay between updates", false, CMD_delay},
77 {'S', "toggle the displaying of system processes", false, CMD_viewsys},
78 {'a', "toggle the displaying of process titles", false, CMD_showargs},
79 {'T', "toggle the displaying of thread IDs", false, CMD_toggletid},
80 {'t', "toggle the display of this process", false, CMD_selftog},
81 {'u', "display processes for only one user (+ selects all users)", false, CMD_user},
82 {'w', "toggle the display of swap use for each process", false, CMD_swaptog},
83 {'z', "toggle the displaying of the system idle process", false, CMD_kidletog},
84 {' ', "update the display", false, CMD_update},
85 {0, NULL, true, CMD_NONE}
86 };
87
88 void
show_help(void)89 show_help(void)
90 {
91 const struct command *curcmd, *nextcmd;
92 char keys[8] = "";
93 _Static_assert(sizeof(keys) >= sizeof("a or b"), "keys right size");
94
95 printf("Top version FreeBSD, %s\n", copyright);
96 curcmd = all_commands;
97 while (curcmd->c != 0) {
98 if (overstrike && !curcmd->available_to_dumb) {
99 ++curcmd;
100 continue;
101 }
102 if (curcmd->desc == NULL) {
103 /* we already printed this */
104 ++curcmd;
105 continue;
106 }
107 nextcmd = curcmd + 1;
108 if (nextcmd->desc == NULL && nextcmd->c != '\0') {
109 sprintf(keys, "%c or %c", curcmd->c, nextcmd->c);
110 } else if (curcmd->c == ' '){
111 /* special case space rather than introducing a "display string" to
112 * the struct */
113 sprintf(keys, "SPC");
114 } else {
115 sprintf(keys, "%c", curcmd->c);
116 }
117 printf("%s\t- %s\n", keys, curcmd->desc);
118 ++curcmd;
119 }
120 if (overstrike)
121 {
122 fputs("\
123 Other commands are also available, but this terminal is not\n\
124 sophisticated enough to handle those commands gracefully.\n", stdout);
125 }
126 }
127
128 /*
129 * Utility routines that help with some of the commands.
130 */
131
132 static char *
next_field(char * str)133 next_field(char *str)
134 {
135 if ((str = strchr(str, ' ')) == NULL)
136 {
137 return(NULL);
138 }
139 *str = '\0';
140 while (*++str == ' ') /* loop */;
141
142 /* if there is nothing left of the string, return NULL */
143 /* This fix is dedicated to Greg Earle */
144 return(*str == '\0' ? NULL : str);
145 }
146
147 static int
scanint(char * str,int * intp)148 scanint(char *str, int *intp)
149 {
150 int val = 0;
151 char ch;
152
153 /* if there is nothing left of the string, flag it as an error */
154 /* This fix is dedicated to Greg Earle */
155 if (*str == '\0')
156 {
157 return(-1);
158 }
159
160 while ((ch = *str++) != '\0')
161 {
162 if (isdigit(ch))
163 {
164 val = val * 10 + (ch - '0');
165 }
166 else if (isspace(ch))
167 {
168 break;
169 }
170 else
171 {
172 return(-1);
173 }
174 }
175 *intp = val;
176 return(0);
177 }
178
179 /*
180 * Some of the commands make system calls that could generate errors.
181 * These errors are collected up in an array of structures for later
182 * contemplation and display. Such routines return a string containing an
183 * error message, or NULL if no errors occurred. The next few routines are
184 * for manipulating and displaying these errors. We need an upper limit on
185 * the number of errors, so we arbitrarily choose 20.
186 */
187
188 #define ERRMAX 20
189
190 static struct errs errs[ERRMAX];
191 static int errcnt;
192 static char err_toomany[] = " too many errors occurred";
193 static char err_listem[] =
194 " Many errors occurred. Press `e' to display the list of errors.";
195
196 /* These macros get used to reset and log the errors */
197 #define ERR_RESET errcnt = 0
198 #define ERROR(p, e) if (errcnt >= ERRMAX) \
199 { \
200 return(err_toomany); \
201 } \
202 else \
203 { \
204 errs[errcnt].arg = (p); \
205 errs[errcnt++].errnum = (e); \
206 }
207
208 /*
209 * err_string() - return an appropriate error string. This is what the
210 * command will return for displaying. If no errors were logged, then
211 * return NULL. The maximum length of the error string is defined by
212 * "STRMAX".
213 */
214
215 #define STRMAX 80
216
217 char *
err_string(void)218 err_string(void)
219 {
220 struct errs *errp;
221 int cnt = 0;
222 bool first = true;
223 int currerr = -1;
224 int stringlen; /* characters still available in "string" */
225 static char string[STRMAX];
226
227 /* if there are no errors, return NULL */
228 if (errcnt == 0)
229 {
230 return(NULL);
231 }
232
233 /* sort the errors */
234 qsort((char *)errs, errcnt, sizeof(struct errs), err_compar);
235
236 /* need a space at the front of the error string */
237 string[0] = ' ';
238 string[1] = '\0';
239 stringlen = STRMAX - 2;
240
241 /* loop thru the sorted list, building an error string */
242 while (cnt < errcnt)
243 {
244 errp = &(errs[cnt++]);
245 if (errp->errnum != currerr)
246 {
247 if (currerr >= 0)
248 {
249 if ((stringlen = str_adderr(string, stringlen, currerr)) < 2)
250 {
251 return(err_listem);
252 }
253 strcat(string, "; "); /* we know there's more */
254 }
255 currerr = errp->errnum;
256 first = true;
257 }
258 if ((stringlen = str_addarg(string, stringlen, errp->arg, first)) ==0)
259 {
260 return(err_listem);
261 }
262 first = false;
263 }
264
265 /* add final message */
266 stringlen = str_adderr(string, stringlen, currerr);
267
268 /* return the error string */
269 return(stringlen == 0 ? err_listem : string);
270 }
271
272 /*
273 * str_adderr(str, len, err) - add an explanation of error "err" to
274 * the string "str".
275 */
276
277 static int
str_adderr(char * str,int len,int err)278 str_adderr(char *str, int len, int err)
279 {
280 const char *msg;
281 int msglen;
282
283 msg = err == 0 ? "Not a number" : strerror(err);
284 msglen = strlen(msg) + 2;
285 if (len <= msglen)
286 {
287 return(0);
288 }
289 strcat(str, ": ");
290 strcat(str, msg);
291 return(len - msglen);
292 }
293
294 /*
295 * str_addarg(str, len, arg, first) - add the string argument "arg" to
296 * the string "str". This is the first in the group when "first"
297 * is set (indicating that a comma should NOT be added to the front).
298 */
299
300 static int
str_addarg(char str[],int len,char arg[],bool first)301 str_addarg(char str[], int len, char arg[], bool first)
302 {
303 int arglen;
304
305 arglen = strlen(arg);
306 if (!first)
307 {
308 arglen += 2;
309 }
310 if (len <= arglen)
311 {
312 return(0);
313 }
314 if (!first)
315 {
316 strcat(str, ", ");
317 }
318 strcat(str, arg);
319 return(len - arglen);
320 }
321
322 /*
323 * err_compar(p1, p2) - comparison routine used by "qsort"
324 * for sorting errors.
325 */
326
327 static int
err_compar(const void * p1,const void * p2)328 err_compar(const void *p1, const void *p2)
329 {
330 int result;
331 const struct errs * const g1 = (const struct errs * const)p1;
332 const struct errs * const g2 = (const struct errs * const)p2;
333
334
335
336 if ((result = g1->errnum - g2->errnum) == 0)
337 {
338 return(strcmp(g1->arg, g2->arg));
339 }
340 return(result);
341 }
342
343 /*
344 * error_count() - return the number of errors currently logged.
345 */
346
347 int
error_count(void)348 error_count(void)
349 {
350 return(errcnt);
351 }
352
353 /*
354 * show_errors() - display on stdout the current log of errors.
355 */
356
357 void
show_errors(void)358 show_errors(void)
359 {
360 int cnt = 0;
361 struct errs *errp = errs;
362
363 printf("%d error%s:\n\n", errcnt, errcnt == 1 ? "" : "s");
364 while (cnt++ < errcnt)
365 {
366 printf("%5s: %s\n", errp->arg,
367 errp->errnum == 0 ? "Not a number" : strerror(errp->errnum));
368 errp++;
369 }
370 }
371
372 static const char no_proc_specified[] = " no processes specified";
373 static const char invalid_signal_number[] = " invalid_signal_number";
374 static const char bad_signal_name[] = " bad signal name";
375 static const char bad_pri_value[] = " bad priority value";
376
377 static int
signame_to_signum(const char * sig)378 signame_to_signum(const char * sig)
379 {
380 int n;
381
382 if (strncasecmp(sig, "SIG", 3) == 0)
383 sig += 3;
384 for (n = 1; n < sys_nsig; n++) {
385 if (!strcasecmp(sys_signame[n], sig))
386 return (n);
387 }
388 return (-1);
389 }
390
391 /*
392 * kill_procs(str) - send signals to processes, much like the "kill"
393 * command does; invoked in response to 'k'.
394 */
395
396 const char *
kill_procs(char * str)397 kill_procs(char *str)
398 {
399 char *nptr;
400 int signum = SIGTERM; /* default */
401 int procnum;
402
403 /* reset error array */
404 ERR_RESET;
405
406 /* skip over leading white space */
407 while (isspace(*str)) str++;
408
409 if (str[0] == '-')
410 {
411 /* explicit signal specified */
412 if ((nptr = next_field(str)) == NULL)
413 {
414 return(no_proc_specified);
415 }
416
417 if (isdigit(str[1]))
418 {
419 scanint(str + 1, &signum);
420 if (signum <= 0 || signum >= NSIG)
421 {
422 return(invalid_signal_number);
423 }
424 }
425 else
426 {
427 signum = signame_to_signum(str + 1);
428
429 /* was it ever found */
430 if (signum == -1 )
431 {
432 return(bad_signal_name);
433 }
434 }
435 /* put the new pointer in place */
436 str = nptr;
437 }
438
439 /* loop thru the string, killing processes */
440 do
441 {
442 if (scanint(str, &procnum) == -1)
443 {
444 ERROR(str, 0);
445 }
446 else
447 {
448 /* go in for the kill */
449 if (kill(procnum, signum) == -1)
450 {
451 /* chalk up an error */
452 ERROR(str, errno);
453 }
454 }
455 } while ((str = next_field(str)) != NULL);
456
457 /* return appropriate error string */
458 return(err_string());
459 }
460
461 /*
462 * renice_procs(str) - change the "nice" of processes, much like the
463 * "renice" command does; invoked in response to 'r'.
464 */
465
466 const char *
renice_procs(char * str)467 renice_procs(char *str)
468 {
469 char negate;
470 int prio;
471 int procnum;
472
473 ERR_RESET;
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 /* check for validity */
492 if (procnum == -1 || prio < PRIO_MIN || prio > PRIO_MAX)
493 {
494 return(bad_pri_value);
495 }
496
497 /* move to the first process number */
498 if ((str = next_field(str)) == NULL)
499 {
500 return(no_proc_specified);
501 }
502
503 /* loop thru the process numbers, renicing each one */
504 do
505 {
506 if (scanint(str, &procnum) == -1)
507 {
508 ERROR(str, 0);
509 }
510
511 if (setpriority(PRIO_PROCESS, procnum, prio) == -1)
512 {
513 ERROR(str, errno);
514 }
515 } while ((str = next_field(str)) != NULL);
516
517 /* return appropriate error string */
518 return(err_string());
519 }
520
521