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
12 /*
13 * This file contains the routines that implement some of the interactive
14 * mode commands. Note that some of the commands are implemented in-line
15 * in "main". This is necessary because they change the global state of
16 * "top" (i.e.: changing the number of processes to display).
17 */
18
19 #include <sys/resource.h>
20 #include <sys/signal.h>
21
22 #include <ctype.h>
23 #include <errno.h>
24 #include <signal.h>
25 #include <stdbool.h>
26 #include <stdlib.h>
27 #include <stdio.h>
28 #include <string.h>
29 #include <unistd.h>
30
31 #include "commands.h"
32 #include "top.h"
33 #include "machine.h"
34
35 static int err_compar(const void *p1, const void *p2);
36
37 struct errs /* structure for a system-call error */
38 {
39 int errnum; /* value of errno (that is, the actual error) */
40 char *arg; /* argument that caused the error */
41 };
42
43 static char *err_string(void);
44 static int str_adderr(char *str, int len, int err);
45 static int str_addarg(char *str, int len, char *arg, bool first);
46
47 /*
48 * show_help() - display the help screen; invoked in response to
49 * either 'h' or '?'.
50 */
51
52 const struct command all_commands[] =
53 {
54 {'C', "toggle the displaying of weighted CPU percentage", false, CMD_wcputog},
55 {'d', "change number of displays to show", false, CMD_displays},
56 {'e', "list errors generated by last \"kill\" or \"renice\" command", false, CMD_errors},
57 {'H', "toggle the displaying of threads", false, CMD_thrtog},
58 {'h', "show this help text", true, CMD_help},
59 {'?', NULL, true, CMD_help},
60 {'/', "filter on command name (+ selects all commands)", false, CMD_grep},
61 {'i', "toggle the displaying of idle processes", false, CMD_idletog},
62 {'I', NULL, false, CMD_idletog},
63 {'j', "toggle the displaying of jail ID", false, CMD_jidtog},
64 {'J', "display processes for only one jail (+ selects all jails)", false, CMD_jail},
65 {'k', "kill processes; send a signal to a list of processes", false, CMD_kill},
66 {'q', "quit" , true, CMD_quit},
67 {'m', "toggle the display between 'cpu' and 'io' modes", false, CMD_viewtog},
68 {'n', "change number of processes to display", false, CMD_number},
69 {'#', NULL, false, CMD_number},
70 {'o', "specify the sort order", false, CMD_order},
71 {'p', "display one process (+ selects all processes)", false, CMD_pid},
72 {'P', "toggle the displaying of per-CPU statistics", false, CMD_pcputog},
73 {'r', "renice a process", false, CMD_renice},
74 {'s', "change number of seconds to delay between updates", false, CMD_delay},
75 {'S', "toggle the displaying of system processes", false, CMD_viewsys},
76 {'a', "toggle the displaying of process titles", false, CMD_showargs},
77 {'T', "toggle the displaying of thread IDs", false, CMD_toggletid},
78 {'t', "toggle the display of this process", false, CMD_selftog},
79 {'u', "display processes for only one user (+ selects all users)", false, CMD_user},
80 {'w', "toggle the display of swap use for each process", false, CMD_swaptog},
81 {'z', "toggle the displaying of the system idle process", false, CMD_kidletog},
82 {' ', "update the display", false, CMD_update},
83 {0, NULL, true, CMD_NONE}
84 };
85
86 void
show_help(void)87 show_help(void)
88 {
89 const struct command *curcmd, *nextcmd;
90 char keys[8] = "";
91 _Static_assert(sizeof(keys) >= sizeof("a or b"), "keys right size");
92
93 printf("Top version FreeBSD, %s\n", copyright);
94 curcmd = all_commands;
95 while (curcmd->c != 0) {
96 if (overstrike && !curcmd->available_to_dumb) {
97 ++curcmd;
98 continue;
99 }
100 if (curcmd->desc == NULL) {
101 /* we already printed this */
102 ++curcmd;
103 continue;
104 }
105 nextcmd = curcmd + 1;
106 if (nextcmd->desc == NULL && nextcmd->c != '\0') {
107 sprintf(keys, "%c or %c", curcmd->c, nextcmd->c);
108 } else if (curcmd->c == ' '){
109 /* special case space rather than introducing a "display string" to
110 * the struct */
111 sprintf(keys, "SPC");
112 } else {
113 sprintf(keys, "%c", curcmd->c);
114 }
115 printf("%s\t- %s\n", keys, curcmd->desc);
116 ++curcmd;
117 }
118 if (overstrike)
119 {
120 fputs("\
121 Other commands are also available, but this terminal is not\n\
122 sophisticated enough to handle those commands gracefully.\n", stdout);
123 }
124 }
125
126 /*
127 * Utility routines that help with some of the commands.
128 */
129
130 static char *
next_field(char * str)131 next_field(char *str)
132 {
133 if ((str = strchr(str, ' ')) == NULL)
134 {
135 return(NULL);
136 }
137 *str = '\0';
138 while (*++str == ' ') /* loop */;
139
140 /* if there is nothing left of the string, return NULL */
141 /* This fix is dedicated to Greg Earle */
142 return(*str == '\0' ? NULL : str);
143 }
144
145 static int
scanint(char * str,int * intp)146 scanint(char *str, int *intp)
147 {
148 int val = 0;
149 char ch;
150
151 /* if there is nothing left of the string, flag it as an error */
152 /* This fix is dedicated to Greg Earle */
153 if (*str == '\0')
154 {
155 return(-1);
156 }
157
158 while ((ch = *str++) != '\0')
159 {
160 if (isdigit(ch))
161 {
162 val = val * 10 + (ch - '0');
163 }
164 else if (isspace(ch))
165 {
166 break;
167 }
168 else
169 {
170 return(-1);
171 }
172 }
173 *intp = val;
174 return(0);
175 }
176
177 /*
178 * Some of the commands make system calls that could generate errors.
179 * These errors are collected up in an array of structures for later
180 * contemplation and display. Such routines return a string containing an
181 * error message, or NULL if no errors occurred. The next few routines are
182 * for manipulating and displaying these errors. We need an upper limit on
183 * the number of errors, so we arbitrarily choose 20.
184 */
185
186 #define ERRMAX 20
187
188 static struct errs errs[ERRMAX];
189 static int errcnt;
190 static char err_toomany[] = " too many errors occurred";
191 static char err_listem[] =
192 " Many errors occurred. Press `e' to display the list of errors.";
193
194 /* These macros get used to reset and log the errors */
195 #define ERR_RESET errcnt = 0
196 #define ERROR(p, e) if (errcnt >= ERRMAX) \
197 { \
198 return(err_toomany); \
199 } \
200 else \
201 { \
202 errs[errcnt].arg = (p); \
203 errs[errcnt++].errnum = (e); \
204 }
205
206 /*
207 * err_string() - return an appropriate error string. This is what the
208 * command will return for displaying. If no errors were logged, then
209 * return NULL. The maximum length of the error string is defined by
210 * "STRMAX".
211 */
212
213 #define STRMAX 80
214
215 char *
err_string(void)216 err_string(void)
217 {
218 struct errs *errp;
219 int cnt = 0;
220 bool first = true;
221 int currerr = -1;
222 int stringlen; /* characters still available in "string" */
223 static char string[STRMAX];
224
225 /* if there are no errors, return NULL */
226 if (errcnt == 0)
227 {
228 return(NULL);
229 }
230
231 /* sort the errors */
232 qsort((char *)errs, errcnt, sizeof(struct errs), err_compar);
233
234 /* need a space at the front of the error string */
235 string[0] = ' ';
236 string[1] = '\0';
237 stringlen = STRMAX - 2;
238
239 /* loop thru the sorted list, building an error string */
240 while (cnt < errcnt)
241 {
242 errp = &(errs[cnt++]);
243 if (errp->errnum != currerr)
244 {
245 if (currerr >= 0)
246 {
247 if ((stringlen = str_adderr(string, stringlen, currerr)) < 2)
248 {
249 return(err_listem);
250 }
251 strcat(string, "; "); /* we know there's more */
252 }
253 currerr = errp->errnum;
254 first = true;
255 }
256 if ((stringlen = str_addarg(string, stringlen, errp->arg, first)) ==0)
257 {
258 return(err_listem);
259 }
260 first = false;
261 }
262
263 /* add final message */
264 stringlen = str_adderr(string, stringlen, currerr);
265
266 /* return the error string */
267 return(stringlen == 0 ? err_listem : string);
268 }
269
270 /*
271 * str_adderr(str, len, err) - add an explanation of error "err" to
272 * the string "str".
273 */
274
275 static int
str_adderr(char * str,int len,int err)276 str_adderr(char *str, int len, int err)
277 {
278 const char *msg;
279 int msglen;
280
281 msg = err == 0 ? "Not a number" : strerror(err);
282 msglen = strlen(msg) + 2;
283 if (len <= msglen)
284 {
285 return(0);
286 }
287 strcat(str, ": ");
288 strcat(str, msg);
289 return(len - msglen);
290 }
291
292 /*
293 * str_addarg(str, len, arg, first) - add the string argument "arg" to
294 * the string "str". This is the first in the group when "first"
295 * is set (indicating that a comma should NOT be added to the front).
296 */
297
298 static int
str_addarg(char str[],int len,char arg[],bool first)299 str_addarg(char str[], int len, char arg[], bool first)
300 {
301 int arglen;
302
303 arglen = strlen(arg);
304 if (!first)
305 {
306 arglen += 2;
307 }
308 if (len <= arglen)
309 {
310 return(0);
311 }
312 if (!first)
313 {
314 strcat(str, ", ");
315 }
316 strcat(str, arg);
317 return(len - arglen);
318 }
319
320 /*
321 * err_compar(p1, p2) - comparison routine used by "qsort"
322 * for sorting errors.
323 */
324
325 static int
err_compar(const void * p1,const void * p2)326 err_compar(const void *p1, const void *p2)
327 {
328 int result;
329 const struct errs * const g1 = (const struct errs * const)p1;
330 const struct errs * const g2 = (const struct errs * const)p2;
331
332
333
334 if ((result = g1->errnum - g2->errnum) == 0)
335 {
336 return(strcmp(g1->arg, g2->arg));
337 }
338 return(result);
339 }
340
341 /*
342 * error_count() - return the number of errors currently logged.
343 */
344
345 int
error_count(void)346 error_count(void)
347 {
348 return(errcnt);
349 }
350
351 /*
352 * show_errors() - display on stdout the current log of errors.
353 */
354
355 void
show_errors(void)356 show_errors(void)
357 {
358 int cnt = 0;
359 struct errs *errp = errs;
360
361 printf("%d error%s:\n\n", errcnt, errcnt == 1 ? "" : "s");
362 while (cnt++ < errcnt)
363 {
364 printf("%5s: %s\n", errp->arg,
365 errp->errnum == 0 ? "Not a number" : strerror(errp->errnum));
366 errp++;
367 }
368 }
369
370 static const char no_proc_specified[] = " no processes specified";
371 static const char invalid_signal_number[] = " invalid_signal_number";
372 static const char bad_signal_name[] = " bad signal name";
373 static const char bad_pri_value[] = " bad priority value";
374
375 static int
signame_to_signum(const char * sig)376 signame_to_signum(const char * sig)
377 {
378 int n;
379
380 if (strncasecmp(sig, "SIG", 3) == 0)
381 sig += 3;
382 for (n = 1; n < sys_nsig; n++) {
383 if (!strcasecmp(sys_signame[n], sig))
384 return (n);
385 }
386 return (-1);
387 }
388
389 /*
390 * kill_procs(str) - send signals to processes, much like the "kill"
391 * command does; invoked in response to 'k'.
392 */
393
394 const char *
kill_procs(char * str)395 kill_procs(char *str)
396 {
397 char *nptr;
398 int signum = SIGTERM; /* default */
399 int procnum;
400
401 /* reset error array */
402 ERR_RESET;
403
404 /* skip over leading white space */
405 while (isspace(*str)) str++;
406
407 if (str[0] == '-')
408 {
409 /* explicit signal specified */
410 if ((nptr = next_field(str)) == NULL)
411 {
412 return(no_proc_specified);
413 }
414
415 if (isdigit(str[1]))
416 {
417 scanint(str + 1, &signum);
418 if (signum <= 0 || signum >= NSIG)
419 {
420 return(invalid_signal_number);
421 }
422 }
423 else
424 {
425 signum = signame_to_signum(str + 1);
426
427 /* was it ever found */
428 if (signum == -1 )
429 {
430 return(bad_signal_name);
431 }
432 }
433 /* put the new pointer in place */
434 str = nptr;
435 }
436
437 /* loop thru the string, killing processes */
438 do
439 {
440 if (scanint(str, &procnum) == -1)
441 {
442 ERROR(str, 0);
443 }
444 else
445 {
446 /* go in for the kill */
447 if (kill(procnum, signum) == -1)
448 {
449 /* chalk up an error */
450 ERROR(str, errno);
451 }
452 }
453 } while ((str = next_field(str)) != NULL);
454
455 /* return appropriate error string */
456 return(err_string());
457 }
458
459 /*
460 * renice_procs(str) - change the "nice" of processes, much like the
461 * "renice" command does; invoked in response to 'r'.
462 */
463
464 const char *
renice_procs(char * str)465 renice_procs(char *str)
466 {
467 char negate;
468 int prio;
469 int procnum;
470
471 ERR_RESET;
472
473 /* allow for negative priority values */
474 if ((negate = (*str == '-')) != 0)
475 {
476 /* move past the minus sign */
477 str++;
478 }
479
480 /* use procnum as a temporary holding place and get the number */
481 procnum = scanint(str, &prio);
482
483 /* negate if necessary */
484 if (negate)
485 {
486 prio = -prio;
487 }
488
489 /* check for validity */
490 if (procnum == -1 || prio < PRIO_MIN || prio > PRIO_MAX)
491 {
492 return(bad_pri_value);
493 }
494
495 /* move to the first process number */
496 if ((str = next_field(str)) == NULL)
497 {
498 return(no_proc_specified);
499 }
500
501 /* loop thru the process numbers, renicing each one */
502 do
503 {
504 if (scanint(str, &procnum) == -1)
505 {
506 ERROR(str, 0);
507 }
508
509 if (setpriority(PRIO_PROCESS, procnum, prio) == -1)
510 {
511 ERROR(str, errno);
512 }
513 } while ((str = next_field(str)) != NULL);
514
515 /* return appropriate error string */
516 return(err_string());
517 }
518
519