xref: /dragonfly/usr.bin/limits/limits.c (revision 6e285212)
1 /*-
2  * Copyright (c) 1997 by
3  * David L. Nugent <davidn@blaze.net.au>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, is permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice immediately at the beginning of the file, without modification,
11  *    this list of conditions, and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. This work was done expressly for inclusion into FreeBSD.  Other use
16  *    is permitted provided this notation is included.
17  * 4. Absolutely no warranty of function or purpose is made by the authors.
18  * 5. Modifications may be freely made to this file providing the above
19  *    conditions are met.
20  *
21  * Display/change(+runprogram)/eval resource limits.
22  *
23  * $FreeBSD: src/usr.bin/limits/limits.c,v 1.7.2.3 2003/05/22 09:26:57 sheldonh Exp $
24  * $DragonFly: src/usr.bin/limits/limits.c,v 1.2 2003/06/17 04:29:28 dillon Exp $
25  */
26 
27 #include <err.h>
28 #include <stdio.h>
29 #include <string.h>
30 #include <sys/types.h>
31 #include <sys/stat.h>
32 #include <sys/param.h>
33 #include <stdlib.h>
34 #include <unistd.h>
35 #include <stdarg.h>
36 #include <ctype.h>
37 #include <errno.h>
38 #include <pwd.h>
39 #include <login_cap.h>
40 #include <sys/time.h>
41 #include <sys/resource.h>
42 
43 enum
44 {
45     SH_NONE,
46     SH_SH,      /* sh */
47     SH_CSH,     /* csh */
48     SH_BASH,    /* gnu bash */
49     SH_TCSH,    /* tcsh */
50     SH_KSH,     /* (pd)ksh */
51     SH_ZSH,     /* zsh */
52     SH_RC,      /* rc or es */
53     SH_NUMBER
54 };
55 
56 
57 /* eval emitter for popular shells.
58  * Why aren't there any standards here? Most shells support either
59  * the csh 'limit' or sh 'ulimit' command, but each varies just
60  * enough that they aren't very compatible from one to the other.
61  */
62 static struct {
63     const char * name;	    /* Name of shell */
64     const char * inf;	    /* Name used for 'unlimited' resource */
65     const char * cmd;	    /* Intro text */
66     const char * hard;	    /* Hard limit text */
67     const char * soft;	    /* Soft limit text */
68     const char * both;	    /* Hard+Soft limit text */
69     struct {
70 	const char * pfx;
71 	const char * sfx;
72 	int divisor;
73     } lprm[RLIM_NLIMITS];
74 } shellparm[] =
75 {
76     { "", "infinity", "Resource limits%s%s:\n", "-max", "-cur", "",
77       {
78 	  { "  cputime%-4s      %8s", " secs\n",  1    },
79 	  { "  filesize%-4s     %8s", " kb\n",    1024 },
80 	  { "  datasize%-4s     %8s", " kb\n",    1024 },
81 	  { "  stacksize%-4s    %8s", " kb\n",    1024 },
82 	  { "  coredumpsize%-4s %8s", " kb\n",    1024 },
83 	  { "  memoryuse%-4s    %8s", " kb\n",    1024 },
84 	  { "  memorylocked%-4s %8s", " kb\n",    1024 },
85 	  { "  maxprocesses%-4s %8s", "\n",       1    },
86 	  { "  openfiles%-4s    %8s", "\n",       1    },
87 	  { "  sbsize%-4s       %8s", " bytes\n", 1    },
88 	  { "  vmemoryuse%-4s   %8s", " kb\n",    1024 }
89       }
90     },
91     { "sh", "unlimited", "", " -H", " -S", "",
92       {
93 	  { "ulimit%s -t %s", ";\n",  1    },
94 	  { "ulimit%s -f %s", ";\n",  512  },
95 	  { "ulimit%s -d %s", ";\n",  1024 },
96 	  { "ulimit%s -s %s", ";\n",  1024 },
97 	  { "ulimit%s -c %s", ";\n",  512  },
98 	  { "ulimit%s -m %s", ";\n",  1024 },
99 	  { "ulimit%s -l %s", ";\n",  1024 },
100 	  { "ulimit%s -u %s", ";\n",  1    },
101 	  { "ulimit%s -n %s", ";\n",  1    },
102 	  { "ulimit%s -b %s", ";\n",  1    },
103 	  { "ulimit%s -v %s", ";\n",  1024 }
104       }
105     },
106     { "csh", "unlimited", "", " -h", "", NULL,
107       {
108 	  { "limit%s cputime %s",      ";\n",  1    },
109 	  { "limit%s filesize %s",     ";\n",  1024 },
110 	  { "limit%s datasize %s",     ";\n",  1024 },
111 	  { "limit%s stacksize %s",    ";\n",  1024 },
112 	  { "limit%s coredumpsize %s", ";\n",  1024 },
113 	  { "limit%s memoryuse %s",    ";\n",  1024 },
114 	  { "limit%s memorylocked %s", ";\n",  1024 },
115 	  { "limit%s maxproc %s",      ";\n",  1    },
116 	  { "limit%s openfiles %s",    ";\n",  1    },
117 	  { "limit%s sbsize %s",       ";\n",  1    },
118 	  { "limit%s vmemoryuse %s",   ";\n",  1024 }
119       }
120     },
121     { "bash|bash2", "unlimited", "", " -H", " -S", "",
122       {
123 	  { "ulimit%s -t %s", ";\n",  1    },
124 	  { "ulimit%s -f %s", ";\n",  1024 },
125 	  { "ulimit%s -d %s", ";\n",  1024 },
126 	  { "ulimit%s -s %s", ";\n",  1024 },
127 	  { "ulimit%s -c %s", ";\n",  1024 },
128 	  { "ulimit%s -m %s", ";\n",  1024 },
129 	  { "ulimit%s -l %s", ";\n",  1024 },
130 	  { "ulimit%s -u %s", ";\n",  1    },
131 	  { "ulimit%s -n %s", ";\n",  1    },
132 	  { "ulimit%s -b %s", ";\n",  1    },
133 	  { "ulimit%s -v %s", ";\n",  1024 }
134       }
135     },
136     { "tcsh", "unlimited", "", " -h", "", NULL,
137       {
138 	  { "limit%s cputime %s",      ";\n",  1    },
139 	  { "limit%s filesize %s",     ";\n",  1024 },
140 	  { "limit%s datasize %s",     ";\n",  1024 },
141 	  { "limit%s stacksize %s",    ";\n",  1024 },
142 	  { "limit%s coredumpsize %s", ";\n",  1024 },
143 	  { "limit%s memoryuse %s",    ";\n",  1024 },
144 	  { "limit%s memorylocked %s", ";\n",  1024 },
145 	  { "limit%s maxproc %s",      ";\n",  1    },
146 	  { "limit%s descriptors %s",  ";\n",  1    },
147 	  { "limit%s sbsize %s",       ";\n",  1    },
148 	  { "limit%s vmemoryuse %s",   ";\n",  1024 }
149       }
150     },
151     { "ksh|pdksh", "unlimited", "", " -H", " -S", "",
152       {
153 	  { "ulimit%s -t %s", ";\n",  1    },
154 	  { "ulimit%s -f %s", ";\n",  512  },
155 	  { "ulimit%s -d %s", ";\n",  1024 },
156 	  { "ulimit%s -s %s", ";\n",  1024 },
157 	  { "ulimit%s -c %s", ";\n",  512  },
158 	  { "ulimit%s -m %s", ";\n",  1024 },
159 	  { "ulimit%s -l %s", ";\n",  1024 },
160 	  { "ulimit%s -p %s", ";\n",  1    },
161 	  { "ulimit%s -n %s", ";\n",  1    },
162 	  { "ulimit%s -b %s", ";\n",  1    },
163 	  { "ulimit%s -v %s", ";\n",  1024 }
164       }
165     },
166     { "zsh", "unlimited", "", " -H", " -S", "",
167       {
168 	  { "ulimit%s -t %s", ";\n",  1    },
169 	  { "ulimit%s -f %s", ";\n",  512  },
170 	  { "ulimit%s -d %s", ";\n",  1024 },
171 	  { "ulimit%s -s %s", ";\n",  1024 },
172 	  { "ulimit%s -c %s", ";\n",  512  },
173 	  { "ulimit%s -m %s", ";\n",  1024 },
174 	  { "ulimit%s -l %s", ";\n",  1024 },
175 	  { "ulimit%s -u %s", ";\n",  1    },
176 	  { "ulimit%s -n %s", ";\n",  1    },
177 	  { "ulimit%s -b %s", ";\n",  1    },
178 	  { "ulimit%s -v %s", ";\n",  1024 }
179       }
180     },
181     { "rc|es", "unlimited", "", " -h", "", NULL,
182       {
183 	  { "limit%s cputime %s",      ";\n",  1    },
184 	  { "limit%s filesize %s",     ";\n",  1024 },
185 	  { "limit%s datasize %s",     ";\n",  1024 },
186 	  { "limit%s stacksize %s",    ";\n",  1024 },
187 	  { "limit%s coredumpsize %s", ";\n",  1024 },
188 	  { "limit%s memoryuse %s",    ";\n",  1024 },
189 	  { "limit%s lockedmemory %s", ";\n",  1024 },
190 	  { "limit%s processes %s",    ";\n",  1    },
191 	  { "limit%s descriptors %s",  ";\n",  1    },
192 	  { "limit%s sbsize %s",       ";\n",  1    },
193 	  { "limit%s vmemoryuse %s",   ";\n",  1024 }
194       }
195     },
196     { NULL }
197 };
198 
199 static struct {
200     const char * cap;
201     rlim_t (*func)(login_cap_t *, const char *, rlim_t, rlim_t);
202 } resources[RLIM_NLIMITS] = {
203     { "cputime",	login_getcaptime },
204     { "filesize",	login_getcapsize },
205     { "datasize",	login_getcapsize },
206     { "stacksize",	login_getcapsize },
207     { "coredumpsize",	login_getcapsize },
208     { "memoryuse",	login_getcapsize },
209     { "memorylocked",	login_getcapsize },
210     { "maxproc",	login_getcapnum  },
211     { "openfiles",	login_getcapnum  },
212     { "sbsize",		login_getcapsize },
213     { "vmemoryuse",	login_getcapsize }
214 };
215 
216 /*
217  * One letter for each resource levels.
218  * NOTE: There is a dependancy on the corresponding
219  * letter index being equal to the resource number.
220  * If sys/resource.h defines are changed, this needs
221  * to be modified accordingly!
222  */
223 
224 #define RCS_STRING  "tfdscmlunbv"
225 
226 static rlim_t resource_num(int which, int ch, const char *str);
227 static void usage(void);
228 static int getshelltype(void);
229 static void print_limit(rlim_t limit, unsigned divisor, const char *inf,
230 			const char *pfx, const char *sfx, const char *which);
231 extern char **environ;
232 
233 static const char rcs_string[] = RCS_STRING;
234 
235 int
236 main(int argc, char *argv[])
237 {
238     char *p, *cls = NULL;
239     char *cleanenv[1];
240     struct passwd * pwd = NULL;
241     int rcswhich, shelltype;
242     int i, num_limits = 0;
243     int ch, doeval = 0, doall = 0;
244     login_cap_t * lc = NULL;
245     enum { ANY=0, SOFT=1, HARD=2, BOTH=3, DISPLAYONLY=4 } type = ANY;
246     enum { RCSUNKNOWN=0, RCSSET=1, RCSSEL=2 } todo = RCSUNKNOWN;
247     int which_limits[RLIM_NLIMITS];
248     rlim_t set_limits[RLIM_NLIMITS];
249     struct rlimit limits[RLIM_NLIMITS];
250 
251     /* init resource tables */
252     for (i = 0; i < RLIM_NLIMITS; i++) {
253 	which_limits[i] = 0; /* Don't set/display any */
254 	set_limits[i] = RLIM_INFINITY;
255 	/* Get current resource values */
256 	getrlimit(i, &limits[i]);
257     }
258 
259     optarg = NULL;
260     while ((ch = getopt(argc, argv, ":EeC:U:BSHabc:d:f:l:m:n:s:t:u:v:")) != -1) {
261 	switch(ch) {
262 	case 'a':
263 	    doall = 1;
264 	    break;
265 	case 'E':
266 	    environ = cleanenv;
267 	    cleanenv[0] = NULL;
268 	    break;
269 	case 'e':
270 	    doeval = 1;
271 	    break;
272 	case 'C':
273 	    cls = optarg;
274 	    break;
275 	case 'U':
276 	    if ((pwd = getpwnam(optarg)) == NULL) {
277 		if (!isdigit(*optarg) ||
278 		    (pwd = getpwuid(atoi(optarg))) == NULL) {
279 		    warnx("invalid user `%s'", optarg);
280 		    usage();
281 		}
282 	    }
283 	    break;
284 	case 'H':
285 	    type = HARD;
286 	    break;
287 	case 'S':
288 	    type = SOFT;
289 	    break;
290 	case 'B':
291 	    type = SOFT|HARD;
292 	    break;
293 	default:
294 	case ':': /* Without arg */
295 	    if ((p = strchr(rcs_string, optopt)) != NULL) {
296 		int rcswhich = p - rcs_string;
297 		if (optarg && *optarg == '-') { /* 'arg' is actually a switch */
298 		    --optind;		/* back one arg, and make arg NULL */
299 		    optarg = NULL;
300 		}
301 		todo = optarg == NULL ? RCSSEL : RCSSET;
302 		if (type == ANY)
303 		    type = BOTH;
304 		which_limits[rcswhich] = optarg ? type : DISPLAYONLY;
305 		set_limits[rcswhich] = resource_num(rcswhich, optopt, optarg);
306 		num_limits++;
307 		break;
308 	    }
309 	    /* FALLTHRU */
310 	case '?':
311 	    usage();
312 	}
313 	optarg = NULL;
314     }
315 
316     /* If user was specified, get class from that */
317     if (pwd != NULL)
318 	lc = login_getpwclass(pwd);
319     else if (cls != NULL && *cls != '\0') {
320 	lc = login_getclassbyname(cls, NULL);
321 	if (lc == NULL || strcmp(cls, lc->lc_class) != 0)
322 	    fprintf(stderr, "login class '%s' non-existent, using %s\n",
323 		    cls, lc?lc->lc_class:"current settings");
324     }
325 
326     /* If we have a login class, update resource table from that */
327     if (lc != NULL) {
328 	for (rcswhich = 0; rcswhich < RLIM_NLIMITS; rcswhich++) {
329 	    char str[40];
330 	    rlim_t val;
331 
332 	    /* current value overridden by resourcename or resourcename-cur */
333 	    sprintf(str, "%s-cur", resources[rcswhich].cap);
334 	    val = resources[rcswhich].func(lc, resources[rcswhich].cap, limits[rcswhich].rlim_cur, limits[rcswhich].rlim_cur);
335 	    limits[rcswhich].rlim_cur = resources[rcswhich].func(lc, str, val, val);
336 	    /* maximum value overridden by resourcename or resourcename-max */
337 	    sprintf(str, "%s-max", resources[rcswhich].cap);
338 	    val = resources[rcswhich].func(lc, resources[rcswhich].cap, limits[rcswhich].rlim_max, limits[rcswhich].rlim_max);
339 	    limits[rcswhich].rlim_max = resources[rcswhich].func(lc, str, val, val);
340 	}
341     }
342 
343     /* now, let's determine what we wish to do with all this */
344 
345     argv += optind;
346 
347     /* If we're setting limits or doing an eval (ie. we're not just
348      * displaying), then check that hard limits are not lower than
349      * soft limits, and force rasing the hard limit if we need to if
350      * we are raising the soft limit, or lower the soft limit if we
351      * are lowering the hard limit.
352      */
353     if ((*argv || doeval) && getuid() == 0) {
354 
355 	for (rcswhich = 0; rcswhich < RLIM_NLIMITS; rcswhich++) {
356 	    if (limits[rcswhich].rlim_max != RLIM_INFINITY) {
357 		if (limits[rcswhich].rlim_cur == RLIM_INFINITY) {
358 		    limits[rcswhich].rlim_max = RLIM_INFINITY;
359 		    which_limits[rcswhich] |= HARD;
360 		} else if (limits[rcswhich].rlim_cur > limits[rcswhich].rlim_max) {
361 		    if (which_limits[rcswhich] == SOFT) {
362 			limits[rcswhich].rlim_max = limits[rcswhich].rlim_cur;
363 			which_limits[rcswhich] |= HARD;
364 		    }  else if (which_limits[rcswhich] == HARD) {
365 			limits[rcswhich].rlim_cur = limits[rcswhich].rlim_max;
366 			which_limits[rcswhich] |= SOFT;
367 		    } else {
368 			/* else.. if we're specifically setting both to
369 			 * silly values, then let it error out.
370 			 */
371 		    }
372 		}
373 	    }
374 	}
375     }
376 
377     /* See if we've overridden anything specific on the command line */
378     if (num_limits && todo == RCSSET) {
379 	for (rcswhich = 0; rcswhich < RLIM_NLIMITS; rcswhich++) {
380 	    if (which_limits[rcswhich] & HARD)
381 		limits[rcswhich].rlim_max = set_limits[rcswhich];
382 	    if (which_limits[rcswhich] & SOFT)
383 		limits[rcswhich].rlim_cur = set_limits[rcswhich];
384 	}
385     }
386 
387     /* If *argv is not NULL, then we are being asked to
388      * (perhaps) set environment variables and run a program
389      */
390     if (*argv) {
391 	if (doeval) {
392 	    warnx("-e cannot be used with `cmd' option");
393 	    usage();
394 	}
395 
396 	login_close(lc);
397 
398 	/* set leading environment variables, like eval(1) */
399 	while (*argv && (p = strchr(*argv, '=')))
400 	    (void)setenv(*argv++, ++p, 1);
401 
402 	/* Set limits */
403 	for (rcswhich = 0; rcswhich < RLIM_NLIMITS; rcswhich++) {
404 	    if (doall || num_limits == 0 || which_limits[rcswhich] != 0)
405 		if (setrlimit(rcswhich, &limits[rcswhich]) == -1)
406 		    err(1, "setrlimit %s", resources[rcswhich].cap);
407 	}
408 
409 	if (*argv == NULL)
410 	    usage();
411 
412 	execvp(*argv, argv);
413 	err(1, "%s", *argv);
414     }
415 
416     shelltype = doeval ? getshelltype() : SH_NONE;
417 
418     if (type == ANY) /* Default to soft limits */
419 	type = SOFT;
420 
421     /* Display limits */
422     printf(shellparm[shelltype].cmd,
423 	   lc ? " for class " : " (current)",
424 	   lc ? lc->lc_class : "");
425 
426     for (rcswhich = 0; rcswhich < RLIM_NLIMITS; rcswhich++) {
427 	if (doall || num_limits == 0 || which_limits[rcswhich] != 0) {
428 	    if (which_limits[rcswhich] == ANY || which_limits[rcswhich])
429 		which_limits[rcswhich] = type;
430 	    if (shellparm[shelltype].lprm[rcswhich].pfx) {
431 		if (shellparm[shelltype].both && limits[rcswhich].rlim_cur == limits[rcswhich].rlim_max) {
432 		    print_limit(limits[rcswhich].rlim_max,
433 				shellparm[shelltype].lprm[rcswhich].divisor,
434 				shellparm[shelltype].inf,
435 				shellparm[shelltype].lprm[rcswhich].pfx,
436 				shellparm[shelltype].lprm[rcswhich].sfx,
437 				shellparm[shelltype].both);
438 		} else {
439 		    if (which_limits[rcswhich] & HARD) {
440 			print_limit(limits[rcswhich].rlim_max,
441 				    shellparm[shelltype].lprm[rcswhich].divisor,
442 				    shellparm[shelltype].inf,
443 				    shellparm[shelltype].lprm[rcswhich].pfx,
444 				    shellparm[shelltype].lprm[rcswhich].sfx,
445 				    shellparm[shelltype].hard);
446 		    }
447 		    if (which_limits[rcswhich] & SOFT) {
448 			print_limit(limits[rcswhich].rlim_cur,
449 				    shellparm[shelltype].lprm[rcswhich].divisor,
450 				    shellparm[shelltype].inf,
451 				    shellparm[shelltype].lprm[rcswhich].pfx,
452 				    shellparm[shelltype].lprm[rcswhich].sfx,
453 				    shellparm[shelltype].soft);
454 		    }
455 		}
456 	    }
457 	}
458     }
459 
460     login_close(lc);
461     exit(EXIT_SUCCESS);
462 }
463 
464 
465 static void
466 usage(void)
467 {
468     (void)fprintf(stderr,
469 "usage: limits [-C class|-U user] [-eaSHBE] [-bcdflmnstuv [val]] [[name=val ...] cmd]\n");
470     exit(EXIT_FAILURE);
471 }
472 
473 static void
474 print_limit(rlim_t limit, unsigned divisor, const char * inf, const char * pfx, const char * sfx, const char * which)
475 {
476     char numbr[64];
477 
478     if (limit == RLIM_INFINITY)
479 	strcpy(numbr, inf);
480     else
481 	sprintf(numbr, "%qd", (quad_t)((limit + divisor/2) / divisor));
482     printf(pfx, which, numbr);
483     printf(sfx, which);
484 
485 }
486 
487 
488 static rlim_t
489 resource_num(int which, int ch, const char *str)
490 {
491     rlim_t res = RLIM_INFINITY;
492 
493     if (str != NULL &&
494 	!(strcasecmp(str, "inf") == 0 ||
495 	  strcasecmp(str, "infinity") == 0 ||
496 	  strcasecmp(str, "unlimit") == 0 ||
497 	  strcasecmp(str, "unlimited") == 0)) {
498 	const char * s = str;
499 	char *e;
500 
501 	switch (which) {
502 	case RLIMIT_CPU:	/* time values */
503 	    errno = 0;
504 	    res = 0;
505 	    while (*s) {
506 		rlim_t tim = strtoq(s, &e, 0);
507 		if (e == NULL || e == s || errno)
508 		    break;
509 		switch (*e++) {
510 		case 0:		   	/* end of string */
511 		    e--;
512 		default:
513 		case 's': case 'S':	/* seconds */
514 		    break;
515 		case 'm': case 'M':	/* minutes */
516 		    tim *= 60L;
517 		    break;
518 		case 'h': case 'H':	/* hours */
519 		    tim *= (60L * 60L);
520 		    break;
521 		case 'd': case 'D':	/* days */
522 		    tim *= (60L * 60L * 24L);
523 		    break;
524 		case 'w': case 'W':	/* weeks */
525 		    tim *= (60L * 60L * 24L * 7L);
526 		case 'y': case 'Y':	/* Years */
527 		    tim *= (60L * 60L * 24L * 365L);
528 		}
529 		s = e;
530 		res += tim;
531 	    }
532 	    break;
533 	case RLIMIT_FSIZE: /* Size values */
534 	case RLIMIT_DATA:
535 	case RLIMIT_STACK:
536 	case RLIMIT_CORE:
537 	case RLIMIT_RSS:
538 	case RLIMIT_MEMLOCK:
539 	case RLIMIT_VMEM:
540 	    errno = 0;
541 	    res = 0;
542 	    while (*s) {
543 		rlim_t mult, tim = strtoq(s, &e, 0);
544 		if (e == NULL || e == s || errno)
545 		    break;
546 		switch (*e++) {
547 		case 0:	/* end of string */
548 		    e--;
549 		default:
550 		    mult = 1;
551 		    break;
552 		case 'b': case 'B':	/* 512-byte blocks */
553 		    mult = 512;
554 		    break;
555 		case 'k': case 'K':	/* 1024-byte Kilobytes */
556 		    mult = 1024;
557 		    break;
558 		case 'm': case 'M':	/* 1024-k kbytes */
559 		    mult = 1024 * 1024;
560 		    break;
561 		case 'g': case 'G':	/* 1Gbyte */
562 		    mult = 1024 * 1024 * 1024;
563 		    break;
564 		case 't': case 'T':	/* 1TBte */
565 		    mult = 1024LL * 1024LL * 1024LL * 1024LL;
566 		    break;
567 		}
568 		s = e;
569 		res += (tim * mult);
570 	    }
571 	    break;
572 	case RLIMIT_NPROC:
573 	case RLIMIT_NOFILE:
574 	    res = strtoq(s, &e, 0);
575 	    s = e;
576 	    break;
577 	}
578 	if (*s) {
579 	    warnx("invalid value -%c `%s'", ch, str);
580 	    usage();
581 	}
582     }
583     return res;
584 }
585 
586 
587 static int
588 getshellbyname(const char * shell)
589 {
590     int i;
591     const char * q;
592     const char * p = strrchr(shell, '/');
593 
594     p = p ? ++p : shell;
595     for (i = 0; (q = shellparm[i].name) != NULL; i++) {
596 	while (*q) {
597 	    int j = strcspn(q, "|");
598 
599 	    if (j == 0)
600 		break;
601 	    if (strncmp(p, q, j) == 0)
602 		return i;
603 	    if (*(q += j))
604 		++q;
605 	}
606     }
607     return SH_SH;
608 }
609 
610 
611 /*
612  * Determine the type of shell our parent process is
613  * This is quite tricky, not 100% reliable and probably
614  * not nearly as thorough as it should be. Basically, this
615  * is a "best guess" only, but hopefully will work in
616  * most cases.
617  */
618 
619 static int
620 getshelltype(void)
621 {
622     pid_t ppid = getppid();
623 
624     if (ppid != 1) {
625 	FILE * fp;
626 	struct stat st;
627 	char procdir[MAXPATHLEN], buf[128];
628 	int l = sprintf(procdir, "/proc/%ld/", (long)ppid);
629 	char * shell = getenv("SHELL");
630 
631 	if (shell != NULL && stat(shell, &st) != -1) {
632 	    struct stat st1;
633 
634 	    strcpy(procdir+l, "file");
635 	    /* $SHELL is actual shell? */
636 	    if (stat(procdir, &st1) != -1 && memcmp(&st, &st1, sizeof st) == 0)
637 		return getshellbyname(shell);
638 	}
639 	strcpy(procdir+l, "status");
640 	if (stat(procdir, &st) == 0 && (fp = fopen(procdir, "r")) != NULL) {
641 	    char * p = fgets(buf, sizeof buf, fp)==NULL ? NULL : strtok(buf, " \t");
642 	    fclose(fp);
643 	    if (p != NULL)
644 		return getshellbyname(p);
645 	}
646     }
647     return SH_SH;
648 }
649 
650