commands.c revision 132038
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: head/contrib/top/commands.c 132038 2004-07-12 15:22:44Z alfred $ 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 33extern int errno; 34 35extern char *copyright; 36 37/* imported from screen.c */ 38extern int overstrike; 39 40int err_compar(); 41char *err_string(); 42 43/* 44 * show_help() - display the help screen; invoked in response to 45 * either 'h' or '?'. 46 */ 47 48show_help() 49 50{ 51 printf("Top version %s, %s\n", version_string(), copyright); 52 fputs("\n\n\ 53A top users display for Unix\n\ 54\n\ 55These single-character commands are available:\n\ 56\n\ 57^L - redraw screen\n\ 58q - quit\n\ 59h or ? - help; show this text\n", stdout); 60 61 /* not all commands are availalbe with overstrike terminals */ 62 if (overstrike) 63 { 64 fputs("\n\ 65Other commands are also available, but this terminal is not\n\ 66sophisticated enough to handle those commands gracefully.\n\n", stdout); 67 } 68 else 69 { 70 fputs("\ 71d - change number of displays to show\n\ 72e - list errors generated by last \"kill\" or \"renice\" command\n\ 73i or I - toggle the displaying of idle processes\n\ 74H - toggle the displaying of threads\n\ 75k - kill processes; send a signal to a list of processes\n\ 76m - toggle the display between 'cpu' and 'io' modes\n\ 77n or # - change number of processes to display\n", stdout); 78#ifdef ORDER 79 if (displaymode == DISP_CPU) 80 fputs("\ 81o - specify sort order (pri, size, res, cpu, time)\n", stdout); 82 else 83 fputs("\ 84o - specify sort order (read, write, fault, total)\n", stdout); 85#endif 86 fputs("\ 87r - renice a process\n\ 88s - change number of seconds to delay between updates\n\ 89S - toggle the displaying of system processes\n\ 90t - toggle the display of this process\n\ 91u - display processes for only one user (+ selects all users)\n\ 92\n\ 93\n", stdout); 94 } 95} 96 97/* 98 * Utility routines that help with some of the commands. 99 */ 100 101char *next_field(str) 102 103register char *str; 104 105{ 106 if ((str = strchr(str, ' ')) == NULL) 107 { 108 return(NULL); 109 } 110 *str = '\0'; 111 while (*++str == ' ') /* loop */; 112 113 /* if there is nothing left of the string, return NULL */ 114 /* This fix is dedicated to Greg Earle */ 115 return(*str == '\0' ? NULL : str); 116} 117 118scanint(str, intp) 119 120char *str; 121int *intp; 122 123{ 124 register int val = 0; 125 register char ch; 126 127 /* if there is nothing left of the string, flag it as an error */ 128 /* This fix is dedicated to Greg Earle */ 129 if (*str == '\0') 130 { 131 return(-1); 132 } 133 134 while ((ch = *str++) != '\0') 135 { 136 if (isdigit(ch)) 137 { 138 val = val * 10 + (ch - '0'); 139 } 140 else if (isspace(ch)) 141 { 142 break; 143 } 144 else 145 { 146 return(-1); 147 } 148 } 149 *intp = val; 150 return(0); 151} 152 153/* 154 * Some of the commands make system calls that could generate errors. 155 * These errors are collected up in an array of structures for later 156 * contemplation and display. Such routines return a string containing an 157 * error message, or NULL if no errors occurred. The next few routines are 158 * for manipulating and displaying these errors. We need an upper limit on 159 * the number of errors, so we arbitrarily choose 20. 160 */ 161 162#define ERRMAX 20 163 164struct errs /* structure for a system-call error */ 165{ 166 int errnum; /* value of errno (that is, the actual error) */ 167 char *arg; /* argument that caused the error */ 168}; 169 170static struct errs errs[ERRMAX]; 171static int errcnt; 172static char *err_toomany = " too many errors occurred"; 173static char *err_listem = 174 " Many errors occurred. Press `e' to display the list of errors."; 175 176/* These macros get used to reset and log the errors */ 177#define ERR_RESET errcnt = 0 178#define ERROR(p, e) if (errcnt >= ERRMAX) \ 179 { \ 180 return(err_toomany); \ 181 } \ 182 else \ 183 { \ 184 errs[errcnt].arg = (p); \ 185 errs[errcnt++].errnum = (e); \ 186 } 187 188/* 189 * err_string() - return an appropriate error string. This is what the 190 * command will return for displaying. If no errors were logged, then 191 * return NULL. The maximum length of the error string is defined by 192 * "STRMAX". 193 */ 194 195#define STRMAX 80 196 197char *err_string() 198 199{ 200 register struct errs *errp; 201 register int cnt = 0; 202 register int first = Yes; 203 register int currerr = -1; 204 int stringlen; /* characters still available in "string" */ 205 static char string[STRMAX]; 206 207 /* if there are no errors, return NULL */ 208 if (errcnt == 0) 209 { 210 return(NULL); 211 } 212 213 /* sort the errors */ 214 qsort((char *)errs, errcnt, sizeof(struct errs), err_compar); 215 216 /* need a space at the front of the error string */ 217 string[0] = ' '; 218 string[1] = '\0'; 219 stringlen = STRMAX - 2; 220 221 /* loop thru the sorted list, building an error string */ 222 while (cnt < errcnt) 223 { 224 errp = &(errs[cnt++]); 225 if (errp->errnum != currerr) 226 { 227 if (currerr != -1) 228 { 229 if ((stringlen = str_adderr(string, stringlen, currerr)) < 2) 230 { 231 return(err_listem); 232 } 233 (void) strcat(string, "; "); /* we know there's more */ 234 } 235 currerr = errp->errnum; 236 first = Yes; 237 } 238 if ((stringlen = str_addarg(string, stringlen, errp->arg, first)) ==0) 239 { 240 return(err_listem); 241 } 242 first = No; 243 } 244 245 /* add final message */ 246 stringlen = str_adderr(string, stringlen, currerr); 247 248 /* return the error string */ 249 return(stringlen == 0 ? err_listem : string); 250} 251 252/* 253 * str_adderr(str, len, err) - add an explanation of error "err" to 254 * the string "str". 255 */ 256 257str_adderr(str, len, err) 258 259char *str; 260int len; 261int err; 262 263{ 264 register char *msg; 265 register int msglen; 266 267 msg = err == 0 ? "Not a number" : errmsg(err); 268 msglen = strlen(msg) + 2; 269 if (len <= msglen) 270 { 271 return(0); 272 } 273 (void) strcat(str, ": "); 274 (void) strcat(str, msg); 275 return(len - msglen); 276} 277 278/* 279 * str_addarg(str, len, arg, first) - add the string argument "arg" to 280 * the string "str". This is the first in the group when "first" 281 * is set (indicating that a comma should NOT be added to the front). 282 */ 283 284str_addarg(str, len, arg, first) 285 286char *str; 287int len; 288char *arg; 289int first; 290 291{ 292 register int arglen; 293 294 arglen = strlen(arg); 295 if (!first) 296 { 297 arglen += 2; 298 } 299 if (len <= arglen) 300 { 301 return(0); 302 } 303 if (!first) 304 { 305 (void) strcat(str, ", "); 306 } 307 (void) strcat(str, arg); 308 return(len - arglen); 309} 310 311/* 312 * err_compar(p1, p2) - comparison routine used by "qsort" 313 * for sorting errors. 314 */ 315 316err_compar(p1, p2) 317 318register struct errs *p1, *p2; 319 320{ 321 register int result; 322 323 if ((result = p1->errnum - p2->errnum) == 0) 324 { 325 return(strcmp(p1->arg, p2->arg)); 326 } 327 return(result); 328} 329 330/* 331 * error_count() - return the number of errors currently logged. 332 */ 333 334error_count() 335 336{ 337 return(errcnt); 338} 339 340/* 341 * show_errors() - display on stdout the current log of errors. 342 */ 343 344show_errors() 345 346{ 347 register int cnt = 0; 348 register struct errs *errp = errs; 349 350 printf("%d error%s:\n\n", errcnt, errcnt == 1 ? "" : "s"); 351 while (cnt++ < errcnt) 352 { 353 printf("%5s: %s\n", errp->arg, 354 errp->errnum == 0 ? "Not a number" : errmsg(errp->errnum)); 355 errp++; 356 } 357} 358 359/* 360 * kill_procs(str) - send signals to processes, much like the "kill" 361 * command does; invoked in response to 'k'. 362 */ 363 364char *kill_procs(str) 365 366char *str; 367 368{ 369 register char *nptr; 370 int signum = SIGTERM; /* default */ 371 int procnum; 372 struct sigdesc *sigp; 373 int uid; 374 375 /* reset error array */ 376 ERR_RESET; 377 378 /* remember our uid */ 379 uid = getuid(); 380 381 /* skip over leading white space */ 382 while (isspace(*str)) str++; 383 384 if (str[0] == '-') 385 { 386 /* explicit signal specified */ 387 if ((nptr = next_field(str)) == NULL) 388 { 389 return(" kill: no processes specified"); 390 } 391 392 if (isdigit(str[1])) 393 { 394 (void) scanint(str + 1, &signum); 395 if (signum <= 0 || signum >= NSIG) 396 { 397 return(" invalid signal number"); 398 } 399 } 400 else 401 { 402 /* translate the name into a number */ 403 for (sigp = sigdesc; sigp->name != NULL; sigp++) 404 { 405 if (strcmp(sigp->name, str + 1) == 0) 406 { 407 signum = sigp->number; 408 break; 409 } 410 } 411 412 /* was it ever found */ 413 if (sigp->name == NULL) 414 { 415 return(" bad signal name"); 416 } 417 } 418 /* put the new pointer in place */ 419 str = nptr; 420 } 421 422 /* loop thru the string, killing processes */ 423 do 424 { 425 if (scanint(str, &procnum) == -1) 426 { 427 ERROR(str, 0); 428 } 429 else 430 { 431 /* check process owner if we're not root */ 432 if (uid && (uid != proc_owner(procnum))) 433 { 434 ERROR(str, EACCES); 435 } 436 /* go in for the kill */ 437 else if (kill(procnum, signum) == -1) 438 { 439 /* chalk up an error */ 440 ERROR(str, errno); 441 } 442 } 443 } while ((str = next_field(str)) != NULL); 444 445 /* return appropriate error string */ 446 return(err_string()); 447} 448 449/* 450 * renice_procs(str) - change the "nice" of processes, much like the 451 * "renice" command does; invoked in response to 'r'. 452 */ 453 454char *renice_procs(str) 455 456char *str; 457 458{ 459 register char negate; 460 int prio; 461 int procnum; 462 int uid; 463 464 ERR_RESET; 465 uid = getuid(); 466 467 /* allow for negative priority values */ 468 if ((negate = (*str == '-')) != 0) 469 { 470 /* move past the minus sign */ 471 str++; 472 } 473 474 /* use procnum as a temporary holding place and get the number */ 475 procnum = scanint(str, &prio); 476 477 /* negate if necessary */ 478 if (negate) 479 { 480 prio = -prio; 481 } 482 483#if defined(PRIO_MIN) && defined(PRIO_MAX) 484 /* check for validity */ 485 if (procnum == -1 || prio < PRIO_MIN || prio > PRIO_MAX) 486 { 487 return(" bad priority value"); 488 } 489#endif 490 491 /* move to the first process number */ 492 if ((str = next_field(str)) == NULL) 493 { 494 return(" no processes specified"); 495 } 496 497 /* loop thru the process numbers, renicing each one */ 498 do 499 { 500 if (scanint(str, &procnum) == -1) 501 { 502 ERROR(str, 0); 503 } 504 505 /* check process owner if we're not root */ 506 else if (uid && (uid != proc_owner(procnum))) 507 { 508 ERROR(str, EACCES); 509 } 510 else if (setpriority(PRIO_PROCESS, procnum, prio) == -1) 511 { 512 ERROR(str, errno); 513 } 514 } while ((str = next_field(str)) != NULL); 515 516 /* return appropriate error string */ 517 return(err_string()); 518} 519 520