xref: /freebsd/usr.bin/limits/limits.c (revision a35d88931c87cfe6bd38f01d7bad22140b3b38f3)
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 
24 #include <sys/cdefs.h>
25 __FBSDID("$FreeBSD$");
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 <stdint.h>
37 #include <ctype.h>
38 #include <errno.h>
39 #include <pwd.h>
40 #include <login_cap.h>
41 #include <sys/time.h>
42 #include <sys/resource.h>
43 
44 enum
45 {
46     SH_NONE,
47     SH_SH,      /* sh */
48     SH_CSH,     /* csh */
49     SH_BASH,    /* gnu bash */
50     SH_TCSH,    /* tcsh */
51     SH_KSH,     /* (pd)ksh */
52     SH_ZSH,     /* zsh */
53     SH_RC,      /* rc or es */
54     SH_NUMBER
55 };
56 
57 
58 /* eval emitter for popular shells.
59  * Why aren't there any standards here? Most shells support either
60  * the csh 'limit' or sh 'ulimit' command, but each varies just
61  * enough that they aren't very compatible from one to the other.
62  */
63 static struct {
64     const char * name;	    /* Name of shell */
65     const char * inf;	    /* Name used for 'unlimited' resource */
66     const char * cmd;	    /* Intro text */
67     const char * hard;	    /* Hard limit text */
68     const char * soft;	    /* Soft limit text */
69     const char * both;	    /* Hard+Soft limit text */
70     struct {
71 	const char * pfx;
72 	const char * sfx;
73 	int divisor;
74     } lprm[RLIM_NLIMITS];
75 } shellparm[] =
76 {
77     { "", "infinity", "Resource limits%s%s:\n", "-max", "-cur", "",
78       {
79 	  { "  cputime%-4s      %8s", " secs\n",  1    },
80 	  { "  filesize%-4s     %8s", " kb\n",    1024 },
81 	  { "  datasize%-4s     %8s", " kb\n",    1024 },
82 	  { "  stacksize%-4s    %8s", " kb\n",    1024 },
83 	  { "  coredumpsize%-4s %8s", " kb\n",    1024 },
84 	  { "  memoryuse%-4s    %8s", " kb\n",    1024 },
85 	  { "  memorylocked%-4s %8s", " kb\n",    1024 },
86 	  { "  maxprocesses%-4s %8s", "\n",       1    },
87 	  { "  openfiles%-4s    %8s", "\n",       1    },
88 	  { "  sbsize%-4s       %8s", " bytes\n", 1    },
89 	  { "  vmemoryuse%-4s   %8s", " kb\n",    1024 }
90       }
91     },
92     { "sh", "unlimited", "", " -H", " -S", "",
93       {
94 	  { "ulimit%s -t %s", ";\n",  1    },
95 	  { "ulimit%s -f %s", ";\n",  512  },
96 	  { "ulimit%s -d %s", ";\n",  1024 },
97 	  { "ulimit%s -s %s", ";\n",  1024 },
98 	  { "ulimit%s -c %s", ";\n",  512  },
99 	  { "ulimit%s -m %s", ";\n",  1024 },
100 	  { "ulimit%s -l %s", ";\n",  1024 },
101 	  { "ulimit%s -u %s", ";\n",  1    },
102 	  { "ulimit%s -n %s", ";\n",  1    },
103 	  { "ulimit%s -b %s", ";\n",  1    },
104 	  { "ulimit%s -v %s", ";\n",  1024 }
105       }
106     },
107     { "csh", "unlimited", "", " -h", "", NULL,
108       {
109 	  { "limit%s cputime %s",      ";\n",  1    },
110 	  { "limit%s filesize %s",     ";\n",  1024 },
111 	  { "limit%s datasize %s",     ";\n",  1024 },
112 	  { "limit%s stacksize %s",    ";\n",  1024 },
113 	  { "limit%s coredumpsize %s", ";\n",  1024 },
114 	  { "limit%s memoryuse %s",    ";\n",  1024 },
115 	  { "limit%s memorylocked %s", ";\n",  1024 },
116 	  { "limit%s maxproc %s",      ";\n",  1    },
117 	  { "limit%s openfiles %s",    ";\n",  1    },
118 	  { "limit%s sbsize %s",       ";\n",  1    },
119 	  { "limit%s vmemoryuse %s",   ";\n",  1024 }
120       }
121     },
122     { "bash|bash2", "unlimited", "", " -H", " -S", "",
123       {
124 	  { "ulimit%s -t %s", ";\n",  1    },
125 	  { "ulimit%s -f %s", ";\n",  1024 },
126 	  { "ulimit%s -d %s", ";\n",  1024 },
127 	  { "ulimit%s -s %s", ";\n",  1024 },
128 	  { "ulimit%s -c %s", ";\n",  1024 },
129 	  { "ulimit%s -m %s", ";\n",  1024 },
130 	  { "ulimit%s -l %s", ";\n",  1024 },
131 	  { "ulimit%s -u %s", ";\n",  1    },
132 	  { "ulimit%s -n %s", ";\n",  1    },
133 	  { "ulimit%s -b %s", ";\n",  1    },
134 	  { "ulimit%s -v %s", ";\n",  1024 }
135       }
136     },
137     { "tcsh", "unlimited", "", " -h", "", NULL,
138       {
139 	  { "limit%s cputime %s",      ";\n",  1    },
140 	  { "limit%s filesize %s",     ";\n",  1024 },
141 	  { "limit%s datasize %s",     ";\n",  1024 },
142 	  { "limit%s stacksize %s",    ";\n",  1024 },
143 	  { "limit%s coredumpsize %s", ";\n",  1024 },
144 	  { "limit%s memoryuse %s",    ";\n",  1024 },
145 	  { "limit%s memorylocked %s", ";\n",  1024 },
146 	  { "limit%s maxproc %s",      ";\n",  1    },
147 	  { "limit%s descriptors %s",  ";\n",  1    },
148 	  { "limit%s sbsize %s",       ";\n",  1    },
149 	  { "limit%s vmemoryuse %s",   ";\n",  1024 }
150       }
151     },
152     { "ksh|pdksh", "unlimited", "", " -H", " -S", "",
153       {
154 	  { "ulimit%s -t %s", ";\n",  1    },
155 	  { "ulimit%s -f %s", ";\n",  512  },
156 	  { "ulimit%s -d %s", ";\n",  1024 },
157 	  { "ulimit%s -s %s", ";\n",  1024 },
158 	  { "ulimit%s -c %s", ";\n",  512  },
159 	  { "ulimit%s -m %s", ";\n",  1024 },
160 	  { "ulimit%s -l %s", ";\n",  1024 },
161 	  { "ulimit%s -p %s", ";\n",  1    },
162 	  { "ulimit%s -n %s", ";\n",  1    },
163 	  { "ulimit%s -b %s", ";\n",  1    },
164 	  { "ulimit%s -v %s", ";\n",  1024 }
165       }
166     },
167     { "zsh", "unlimited", "", " -H", " -S", "",
168       {
169 	  { "ulimit%s -t %s", ";\n",  1    },
170 	  { "ulimit%s -f %s", ";\n",  512  },
171 	  { "ulimit%s -d %s", ";\n",  1024 },
172 	  { "ulimit%s -s %s", ";\n",  1024 },
173 	  { "ulimit%s -c %s", ";\n",  512  },
174 	  { "ulimit%s -m %s", ";\n",  1024 },
175 	  { "ulimit%s -l %s", ";\n",  1024 },
176 	  { "ulimit%s -u %s", ";\n",  1    },
177 	  { "ulimit%s -n %s", ";\n",  1    },
178 	  { "ulimit%s -b %s", ";\n",  1    },
179 	  { "ulimit%s -v %s", ";\n",  1024 }
180       }
181     },
182     { "rc|es", "unlimited", "", " -h", "", NULL,
183       {
184 	  { "limit%s cputime %s",      ";\n",  1    },
185 	  { "limit%s filesize %s",     ";\n",  1024 },
186 	  { "limit%s datasize %s",     ";\n",  1024 },
187 	  { "limit%s stacksize %s",    ";\n",  1024 },
188 	  { "limit%s coredumpsize %s", ";\n",  1024 },
189 	  { "limit%s memoryuse %s",    ";\n",  1024 },
190 	  { "limit%s lockedmemory %s", ";\n",  1024 },
191 	  { "limit%s processes %s",    ";\n",  1    },
192 	  { "limit%s descriptors %s",  ";\n",  1    },
193 	  { "limit%s sbsize %s",       ";\n",  1    },
194 	  { "limit%s vmemoryuse %s",   ";\n",  1024 }
195       }
196     },
197     { NULL, NULL, NULL, NULL, NULL, NULL,
198       { }
199     }
200 };
201 
202 static struct {
203     const char * cap;
204     rlim_t (*func)(login_cap_t *, const char *, rlim_t, rlim_t);
205 } resources[RLIM_NLIMITS] = {
206     { "cputime",	login_getcaptime },
207     { "filesize",	login_getcapsize },
208     { "datasize",	login_getcapsize },
209     { "stacksize",	login_getcapsize },
210     { "coredumpsize",	login_getcapsize },
211     { "memoryuse",	login_getcapsize },
212     { "memorylocked",	login_getcapsize },
213     { "maxproc",	login_getcapnum  },
214     { "openfiles",	login_getcapnum  },
215     { "sbsize",		login_getcapsize  },
216     { "vmemoryuse",	login_getcapsize  }
217 };
218 
219 /*
220  * One letter for each resource levels.
221  * NOTE: There is a dependancy on the corresponding
222  * letter index being equal to the resource number.
223  * If sys/resource.h defines are changed, this needs
224  * to be modified accordingly!
225  */
226 
227 #define RCS_STRING  "tfdscmlunbv"
228 
229 static rlim_t resource_num(int which, int ch, const char *str);
230 static void usage(void);
231 static int getshelltype(void);
232 static void print_limit(rlim_t limit, unsigned divisor, const char *inf,
233 			const char *pfx, const char *sfx, const char *which);
234 extern char **environ;
235 
236 static const char rcs_string[] = RCS_STRING;
237 
238 int
239 main(int argc, char *argv[])
240 {
241     char *p, *cls = NULL;
242     char *cleanenv[1];
243     struct passwd * pwd = NULL;
244     int rcswhich, shelltype;
245     int i, num_limits = 0;
246     int ch, doeval = 0, doall = 0;
247     login_cap_t * lc = NULL;
248     enum { ANY=0, SOFT=1, HARD=2, BOTH=3, DISPLAYONLY=4 } type = ANY;
249     enum { RCSUNKNOWN=0, RCSSET=1, RCSSEL=2 } todo = RCSUNKNOWN;
250     int which_limits[RLIM_NLIMITS];
251     rlim_t set_limits[RLIM_NLIMITS];
252     struct rlimit limits[RLIM_NLIMITS];
253 
254     /* init resource tables */
255     for (i = 0; i < RLIM_NLIMITS; i++) {
256 	which_limits[i] = 0; /* Don't set/display any */
257 	set_limits[i] = RLIM_INFINITY;
258 	/* Get current resource values */
259 	getrlimit(i, &limits[i]);
260     }
261 
262     optarg = NULL;
263     while ((ch = getopt(argc, argv, ":EeC:U:BSHab:c:d:f:l:m:n:s:t:u:v:")) != -1) {
264 	switch(ch) {
265 	case 'a':
266 	    doall = 1;
267 	    break;
268 	case 'E':
269 	    environ = cleanenv;
270 	    cleanenv[0] = NULL;
271 	    break;
272 	case 'e':
273 	    doeval = 1;
274 	    break;
275 	case 'C':
276 	    cls = optarg;
277 	    break;
278 	case 'U':
279 	    if ((pwd = getpwnam(optarg)) == NULL) {
280 		if (!isdigit(*optarg) ||
281 		    (pwd = getpwuid(atoi(optarg))) == NULL) {
282 		    warnx("invalid user `%s'", optarg);
283 		    usage();
284 		}
285 	    }
286 	    break;
287 	case 'H':
288 	    type = HARD;
289 	    break;
290 	case 'S':
291 	    type = SOFT;
292 	    break;
293 	case 'B':
294 	    type = SOFT|HARD;
295 	    break;
296 	default:
297 	case ':': /* Without arg */
298 	    if ((p = strchr(rcs_string, optopt)) != NULL) {
299 		int rcswhich1 = p - rcs_string;
300 		if (optarg && *optarg == '-') { /* 'arg' is actually a switch */
301 		    --optind;		/* back one arg, and make arg NULL */
302 		    optarg = NULL;
303 		}
304 		todo = optarg == NULL ? RCSSEL : RCSSET;
305 		if (type == ANY)
306 		    type = BOTH;
307 		which_limits[rcswhich1] = optarg ? type : DISPLAYONLY;
308 		set_limits[rcswhich1] = resource_num(rcswhich1, optopt, optarg);
309 		num_limits++;
310 		break;
311 	    }
312 	    /* FALLTHRU */
313 	case '?':
314 	    usage();
315 	}
316 	optarg = NULL;
317     }
318 
319     /* If user was specified, get class from that */
320     if (pwd != NULL)
321 	lc = login_getpwclass(pwd);
322     else if (cls != NULL && *cls != '\0') {
323 	lc = login_getclassbyname(cls, NULL);
324 	if (lc == NULL || strcmp(cls, lc->lc_class) != 0)
325 	    fprintf(stderr, "login class '%s' non-existent, using %s\n",
326 		    cls, lc?lc->lc_class:"current settings");
327     }
328 
329     /* If we have a login class, update resource table from that */
330     if (lc != NULL) {
331 	for (rcswhich = 0; rcswhich < RLIM_NLIMITS; rcswhich++) {
332 	    char str[40];
333 	    rlim_t val;
334 
335 	    /* current value overridden by resourcename or resourcename-cur */
336 	    sprintf(str, "%s-cur", resources[rcswhich].cap);
337 	    val = resources[rcswhich].func(lc, resources[rcswhich].cap, limits[rcswhich].rlim_cur, limits[rcswhich].rlim_cur);
338 	    limits[rcswhich].rlim_cur = resources[rcswhich].func(lc, str, val, val);
339 	    /* maximum value overridden by resourcename or resourcename-max */
340 	    sprintf(str, "%s-max", resources[rcswhich].cap);
341 	    val = resources[rcswhich].func(lc, resources[rcswhich].cap, limits[rcswhich].rlim_max, limits[rcswhich].rlim_max);
342 	    limits[rcswhich].rlim_max = resources[rcswhich].func(lc, str, val, val);
343 	}
344     }
345 
346     /* now, let's determine what we wish to do with all this */
347 
348     argv += optind;
349 
350     /* If we're setting limits or doing an eval (ie. we're not just
351      * displaying), then check that hard limits are not lower than
352      * soft limits, and force rasing the hard limit if we need to if
353      * we are raising the soft limit, or lower the soft limit if we
354      * are lowering the hard limit.
355      */
356     if ((*argv || doeval) && getuid() == 0) {
357 
358 	for (rcswhich = 0; rcswhich < RLIM_NLIMITS; rcswhich++) {
359 	    if (limits[rcswhich].rlim_max != RLIM_INFINITY) {
360 		if (limits[rcswhich].rlim_cur == RLIM_INFINITY) {
361 		    limits[rcswhich].rlim_max = RLIM_INFINITY;
362 		    which_limits[rcswhich] |= HARD;
363 		} else if (limits[rcswhich].rlim_cur > limits[rcswhich].rlim_max) {
364 		    if (which_limits[rcswhich] == SOFT) {
365 			limits[rcswhich].rlim_max = limits[rcswhich].rlim_cur;
366 			which_limits[rcswhich] |= HARD;
367 		    }  else if (which_limits[rcswhich] == HARD) {
368 			limits[rcswhich].rlim_cur = limits[rcswhich].rlim_max;
369 			which_limits[rcswhich] |= SOFT;
370 		    } else {
371 			/* else.. if we're specifically setting both to
372 			 * silly values, then let it error out.
373 			 */
374 		    }
375 		}
376 	    }
377 	}
378     }
379 
380     /* See if we've overridden anything specific on the command line */
381     if (num_limits && todo == RCSSET) {
382 	for (rcswhich = 0; rcswhich < RLIM_NLIMITS; rcswhich++) {
383 	    if (which_limits[rcswhich] & HARD)
384 		limits[rcswhich].rlim_max = set_limits[rcswhich];
385 	    if (which_limits[rcswhich] & SOFT)
386 		limits[rcswhich].rlim_cur = set_limits[rcswhich];
387 	}
388     }
389 
390     /* If *argv is not NULL, then we are being asked to
391      * (perhaps) set environment variables and run a program
392      */
393     if (*argv) {
394 	if (doeval) {
395 	    warnx("-e cannot be used with `cmd' option");
396 	    usage();
397 	}
398 
399 	login_close(lc);
400 
401 	/* set leading environment variables, like eval(1) */
402 	while (*argv && (p = strchr(*argv, '=')))
403 	    (void)setenv(*argv++, ++p, 1);
404 
405 	/* Set limits */
406 	for (rcswhich = 0; rcswhich < RLIM_NLIMITS; rcswhich++) {
407 	    if (doall || num_limits == 0 || which_limits[rcswhich] != 0)
408 		if (setrlimit(rcswhich, &limits[rcswhich]) == -1)
409 		    err(1, "setrlimit %s", resources[rcswhich].cap);
410 	}
411 
412 	if (*argv == NULL)
413 	    usage();
414 
415 	execvp(*argv, argv);
416 	err(1, "%s", *argv);
417     }
418 
419     shelltype = doeval ? getshelltype() : SH_NONE;
420 
421     if (type == ANY) /* Default to soft limits */
422 	type = SOFT;
423 
424     /* Display limits */
425     printf(shellparm[shelltype].cmd,
426 	   lc ? " for class " : " (current)",
427 	   lc ? lc->lc_class : "");
428 
429     for (rcswhich = 0; rcswhich < RLIM_NLIMITS; rcswhich++) {
430 	if (doall || num_limits == 0 || which_limits[rcswhich] != 0) {
431 	    if (which_limits[rcswhich] == ANY || which_limits[rcswhich])
432 		which_limits[rcswhich] = type;
433 	    if (shellparm[shelltype].lprm[rcswhich].pfx) {
434 		if (shellparm[shelltype].both && limits[rcswhich].rlim_cur == limits[rcswhich].rlim_max) {
435 		    print_limit(limits[rcswhich].rlim_max,
436 				shellparm[shelltype].lprm[rcswhich].divisor,
437 				shellparm[shelltype].inf,
438 				shellparm[shelltype].lprm[rcswhich].pfx,
439 				shellparm[shelltype].lprm[rcswhich].sfx,
440 				shellparm[shelltype].both);
441 		} else {
442 		    if (which_limits[rcswhich] & HARD) {
443 			print_limit(limits[rcswhich].rlim_max,
444 				    shellparm[shelltype].lprm[rcswhich].divisor,
445 				    shellparm[shelltype].inf,
446 				    shellparm[shelltype].lprm[rcswhich].pfx,
447 				    shellparm[shelltype].lprm[rcswhich].sfx,
448 				    shellparm[shelltype].hard);
449 		    }
450 		    if (which_limits[rcswhich] & SOFT) {
451 			print_limit(limits[rcswhich].rlim_cur,
452 				    shellparm[shelltype].lprm[rcswhich].divisor,
453 				    shellparm[shelltype].inf,
454 				    shellparm[shelltype].lprm[rcswhich].pfx,
455 				    shellparm[shelltype].lprm[rcswhich].sfx,
456 				    shellparm[shelltype].soft);
457 		    }
458 		}
459 	    }
460 	}
461     }
462 
463     login_close(lc);
464     exit(EXIT_SUCCESS);
465 }
466 
467 
468 static void
469 usage(void)
470 {
471     (void)fprintf(stderr,
472 "usage: limits [-C class|-U user] [-eaSHBE] [-bcdflmnstuv [val]] [[name=val ...] cmd]\n");
473     exit(EXIT_FAILURE);
474 }
475 
476 static void
477 print_limit(rlim_t limit, unsigned divisor, const char * inf, const char * pfx, const char * sfx, const char * which)
478 {
479     char numbr[64];
480 
481     if (limit == RLIM_INFINITY)
482 	strcpy(numbr, inf);
483     else
484 	sprintf(numbr, "%jd", (intmax_t)((limit + divisor/2) / divisor));
485     printf(pfx, which, numbr);
486     printf(sfx, which);
487 
488 }
489 
490 
491 static rlim_t
492 resource_num(int which, int ch, const char *str)
493 {
494     rlim_t res = RLIM_INFINITY;
495 
496     if (str != NULL &&
497 	!(strcasecmp(str, "inf") == 0 ||
498 	  strcasecmp(str, "infinity") == 0 ||
499 	  strcasecmp(str, "unlimit") == 0 ||
500 	  strcasecmp(str, "unlimited") == 0)) {
501 	const char * s = str;
502 	char *e;
503 
504 	switch (which) {
505 	case RLIMIT_CPU:	/* time values */
506 	    errno = 0;
507 	    res = 0;
508 	    while (*s) {
509 		rlim_t tim = strtoq(s, &e, 0);
510 		if (e == NULL || e == s || errno)
511 		    break;
512 		switch (*e++) {
513 		case 0:		   	/* end of string */
514 		    e--;
515 		default:
516 		case 's': case 'S':	/* seconds */
517 		    break;
518 		case 'm': case 'M':	/* minutes */
519 		    tim *= 60L;
520 		    break;
521 		case 'h': case 'H':	/* hours */
522 		    tim *= (60L * 60L);
523 		    break;
524 		case 'd': case 'D':	/* days */
525 		    tim *= (60L * 60L * 24L);
526 		    break;
527 		case 'w': case 'W':	/* weeks */
528 		    tim *= (60L * 60L * 24L * 7L);
529 		case 'y': case 'Y':	/* Years */
530 		    tim *= (60L * 60L * 24L * 365L);
531 		}
532 		s = e;
533 		res += tim;
534 	    }
535 	    break;
536 	case RLIMIT_FSIZE: /* Size values */
537 	case RLIMIT_DATA:
538 	case RLIMIT_STACK:
539 	case RLIMIT_CORE:
540 	case RLIMIT_RSS:
541 	case RLIMIT_MEMLOCK:
542 	case RLIMIT_SBSIZE:
543 	case RLIMIT_VMEM:
544 	    errno = 0;
545 	    res = 0;
546 	    while (*s) {
547 		rlim_t mult, tim = strtoq(s, &e, 0);
548 		if (e == NULL || e == s || errno)
549 		    break;
550 		switch (*e++) {
551 		case 0:	/* end of string */
552 		    e--;
553 		default:
554 		    mult = 1;
555 		    break;
556 		case 'b': case 'B':	/* 512-byte blocks */
557 		    mult = 512;
558 		    break;
559 		case 'k': case 'K':	/* 1024-byte Kilobytes */
560 		    mult = 1024;
561 		    break;
562 		case 'm': case 'M':	/* 1024-k kbytes */
563 		    mult = 1024 * 1024;
564 		    break;
565 		case 'g': case 'G':	/* 1Gbyte */
566 		    mult = 1024 * 1024 * 1024;
567 		    break;
568 		case 't': case 'T':	/* 1TBte */
569 		    mult = 1024LL * 1024LL * 1024LL * 1024LL;
570 		    break;
571 		}
572 		s = e;
573 		res += (tim * mult);
574 	    }
575 	    break;
576 	case RLIMIT_NPROC:
577 	case RLIMIT_NOFILE:
578 	    res = strtoq(s, &e, 0);
579 	    s = e;
580 	    break;
581 	}
582 	if (*s) {
583 	    warnx("invalid value -%c `%s'", ch, str);
584 	    usage();
585 	}
586     }
587     return res;
588 }
589 
590 
591 static int
592 getshellbyname(const char * shell)
593 {
594     int i;
595     const char * q;
596     const char * p = strrchr(shell, '/');
597 
598     p = p ? p+1 : shell;
599     for (i = 0; (q = shellparm[i].name) != NULL; i++) {
600 	while (*q) {
601 	    int j = strcspn(q, "|");
602 
603 	    if (j == 0)
604 		break;
605 	    if (strncmp(p, q, j) == 0)
606 		return i;
607 	    if (*(q += j))
608 		++q;
609 	}
610     }
611     return SH_SH;
612 }
613 
614 
615 /*
616  * Determine the type of shell our parent process is
617  * This is quite tricky, not 100% reliable and probably
618  * not nearly as thorough as it should be. Basically, this
619  * is a "best guess" only, but hopefully will work in
620  * most cases.
621  */
622 
623 static int
624 getshelltype(void)
625 {
626     pid_t ppid = getppid();
627 
628     if (ppid != 1) {
629 	FILE * fp;
630 	struct stat st;
631 	char procdir[MAXPATHLEN], buf[128];
632 	int l = sprintf(procdir, "/proc/%ld/", (long)ppid);
633 	char * shell = getenv("SHELL");
634 
635 	if (shell != NULL && stat(shell, &st) != -1) {
636 	    struct stat st1;
637 
638 	    strcpy(procdir+l, "file");
639 	    /* $SHELL is actual shell? */
640 	    if (stat(procdir, &st1) != -1 && memcmp(&st, &st1, sizeof st) == 0)
641 		return getshellbyname(shell);
642 	}
643 	strcpy(procdir+l, "status");
644 	if (stat(procdir, &st) == 0 && (fp = fopen(procdir, "r")) != NULL) {
645 	    char * p = fgets(buf, sizeof buf, fp)==NULL ? NULL : strtok(buf, " \t");
646 	    fclose(fp);
647 	    if (p != NULL)
648 		return getshellbyname(p);
649 	}
650     }
651     return SH_SH;
652 }
653 
654