bin/sh/options.c

   1 /*-
   2  * Copyright (c) 1991, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Kenneth Almquist.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. All advertising materials mentioning features or use of this software
  17  *    must display the following acknowledgement:
  18  *      This product includes software developed by the University of
  19  *      California, Berkeley and its contributors.
  20  * 4. Neither the name of the University nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  *
  36  * @(#)options.c        8.2 (Berkeley) 5/4/95
  37  * $FreeBSD: src/bin/sh/options.c,v 1.25 2006/04/09 12:20:42 stefanf Exp $
  38  * $DragonFly: src/bin/sh/options.c,v 1.7 2007/01/14 04:41:32 pavalos Exp $
  39  */
  40
  41 #include <signal.h>
  42 #include <unistd.h>
  43 #include <stdlib.h>
  44
  45 #include "shell.h"
  46 #define DEFINE_OPTIONS
  47 #include "options.h"
  48 #undef DEFINE_OPTIONS
  49 #include "nodes.h"      /* for other header files */
  50 #include "eval.h"
  51 #include "jobs.h"
  52 #include "input.h"
  53 #include "output.h"
  54 #include "trap.h"
  55 #include "var.h"
  56 #include "memalloc.h"
  57 #include "error.h"
  58 #include "mystring.h"
  59 #ifndef NO_HISTORY
  60 #include "myhistedit.h"
  61 #endif
  62
  63 char *arg0;                     /* value of $0 */
  64 struct shparam shellparam;      /* current positional parameters */
  65 char **argptr;                  /* argument list for builtin commands */
  66 const char *shoptarg;           /* set by nextopt (like getopt) */
  67 const char *optptr;             /* used by nextopt */
  68
  69 char *minusc;                   /* argument to -c option */
  70
  71
  72 STATIC void options(int);
  73 STATIC void minus_o(char *, int);
  74 STATIC void setoption(int, int);
  75 STATIC int getopts(char *, char *, char **, char ***, char **);
  76
  77
  78 /*
  79  * Process the shell command line arguments.
  80  */
  81
  82 void
  83 procargs(int argc, char **argv)
  84 {
  85         int i;
  86
  87         argptr = argv;
  88         if (argc > 0)
  89                 argptr++;
  90         for (i = 0; i < NOPTS; i++)
  91                 optlist[i].val = 2;
  92         privileged = (getuid() != geteuid() || getgid() != getegid());
  93         options(1);
  94         if (*argptr == NULL && minusc == NULL)
  95                 sflag = 1;
  96         if (iflag == 2 && sflag == 1 && isatty(0) && isatty(1))
  97                 iflag = 1;
  98         if (mflag == 2)
  99                 mflag = iflag;
 100         /* turn on tabcomplete in an interactive shell by default */
 101         tabcomplete = iflag;
 102         for (i = 0; i < NOPTS; i++)
 103                 if (optlist[i].val == 2)
 104                         optlist[i].val = 0;
 105         arg0 = argv[0];
 106         if (sflag == 0 && minusc == NULL) {
 107                 commandname = arg0 = *argptr++;
 108                 setinputfile(commandname, 0);
 109         }
 110         /* POSIX 1003.2: first arg after -c cmd is $0, remainder $1... */
 111         if (argptr && minusc && *argptr)
 112                 arg0 = *argptr++;
 113
 114         shellparam.p = argptr;
 115         shellparam.reset = 1;
 116         /* assert(shellparam.malloc == 0 && shellparam.nparam == 0); */
 117         while (*argptr) {
 118                 shellparam.nparam++;
 119                 argptr++;
 120         }
 121         optschanged();
 122 }
 123
 124
 125 void
 126 optschanged(void)
 127 {
 128         setinteractive(iflag);
 129 #ifndef NO_HISTORY
 130         histedit();
 131 #endif
 132         setjobctl(mflag);
 133 }
 134
 135 /*
 136  * Process shell options.  The global variable argptr contains a pointer
 137  * to the argument list; we advance it past the options.
 138  */
 139
 140 STATIC void
 141 options(int cmdline)
 142 {
 143         char *kp, *p;
 144         int val;
 145         int c;
 146
 147         if (cmdline)
 148                 minusc = NULL;
 149         while ((p = *argptr) != NULL) {
 150                 argptr++;
 151                 if ((c = *p++) == '-') {
 152                         val = 1;
 153                         /* A "-" or  "--" terminates options */
 154                         if (p[0] == '\0')
 155                                 goto end_options1;
 156                         if (p[0] == '-' && p[1] == '\0')
 157                                 goto end_options2;
 158                         /**
 159                          * For the benefit of `#!' lines in shell scripts,
 160                          * treat a string of '-- *#.*' the same as '--'.
 161                          * This is needed so that a script starting with:
 162                          *      #!/bin/sh -- # -*- perl -*-
 163                          * will continue to work after a change is made to
 164                          * kern/imgact_shell.c to NOT token-ize the options
 165                          * specified on a '#!' line.  A bit of a kludge,
 166                          * but that trick is recommended in documentation
 167                          * for some scripting languages, and we might as
 168                          * well continue to support it.
 169                          */
 170                         if (p[0] == '-') {
 171                                 kp = p + 1;
 172                                 while (*kp == ' ' || *kp == '\t')
 173                                         kp++;
 174                                 if (*kp == '#' || *kp == '\0')
 175                                         goto end_options2;
 176                         }
 177                 } else if (c == '+') {
 178                         val = 0;
 179                 } else {
 180                         argptr--;
 181                         break;
 182                 }
 183                 while ((c = *p++) != '\0') {
 184                         if (c == 'c' && cmdline) {
 185                                 char *q;
 186 #ifdef NOHACK   /* removing this code allows sh -ce 'foo' for compat */
 187                                 if (*p == '\0')
 188 #endif
 189                                         q = *argptr++;
 190                                 if (q == NULL || minusc != NULL)
 191                                         error("Bad -c option");
 192                                 minusc = q;
 193 #ifdef NOHACK
 194                                 break;
 195 #endif
 196                         } else if (c == 'o') {
 197                                 minus_o(*argptr, val);
 198                                 if (*argptr)
 199                                         argptr++;
 200                         } else {
 201                                 if (c == 'p' && !val && privileged) {
 202                                         setuid(getuid());
 203                                         setgid(getgid());
 204                                 }
 205                                 setoption(c, val);
 206                         }
 207                 }
 208         }
 209         return;
 210
 211         /* When processing `set', a single "-" means turn off -x and -v */
 212 end_options1:
 213         if (!cmdline) {
 214                 xflag = vflag = 0;
 215                 return;
 216         }
 217
 218         /*
 219          * When processing `set', a "--" means the remaining arguments
 220          * replace the positional parameters in the active shell.  If
 221          * there are no remaining options, then all the positional
 222          * parameters are cleared (equivalent to doing ``shift $#'').
 223          */
 224 end_options2:
 225         if (!cmdline) {
 226                 if (*argptr == NULL)
 227                         setparam(argptr);
 228                 return;
 229         }
 230
 231         /*
 232          * At this point we are processing options given to 'sh' on a command
 233          * line.  If an end-of-options marker ("-" or "--") is followed by an
 234          * arg of "#", then skip over all remaining arguments.  Some scripting
 235          * languages (e.g.: perl) document that /bin/sh will implement this
 236          * behavior, and they recommend that users take advantage of it to
 237          * solve certain issues that can come up when writing a perl script.
 238          * Yes, this feature is in /bin/sh to help users write perl scripts.
 239          */
 240         p = *argptr;
 241         if (p != NULL && p[0] == '#' && p[1] == '\0') {
 242                 while (*argptr != NULL)
 243                         argptr++;
 244                 /* We need to keep the final argument */
 245                 argptr--;
 246         }
 247 }
 248
 249 STATIC void
 250 minus_o(char *name, int val)
 251 {
 252         int i;
 253
 254         if (name == NULL) {
 255                 if (val) {
 256                         /* "Pretty" output. */
 257                         out1str("Current option settings\n");
 258                         for (i = 0; i < NOPTS; i++)
 259                                 out1fmt("%-16s%s\n", optlist[i].name,
 260                                         optlist[i].val ? "on" : "off");
 261                 } else {
 262                         /* Output suitable for re-input to shell. */
 263                         for (i = 0; i < NOPTS; i++) {
 264                                 if (i % 6 == 0)
 265                                         out1str(i == 0 ? "set" : "\nset");
 266                                 out1fmt(" %co %s", optlist[i].val ? '-' : '+',
 267                                         optlist[i].name);
 268                         }
 269                         out1c('\n');
 270                 }
 271         } else {
 272                 for (i = 0; i < NOPTS; i++)
 273                         if (equal(name, optlist[i].name)) {
 274                                 if (!val && privileged && equal(name, "privileged")) {
 275                                         setuid(getuid());
 276                                         setgid(getgid());
 277                                 }
 278                                 setoption(optlist[i].letter, val);
 279                                 return;
 280                         }
 281                 error("Illegal option -o %s", name);
 282         }
 283 }
 284
 285
 286 STATIC void
 287 setoption(int flag, int val)
 288 {
 289         int i;
 290
 291         for (i = 0; i < NOPTS; i++)
 292                 if (optlist[i].letter == flag) {
 293                         optlist[i].val = val;
 294                         if (val) {
 295                                 /* #%$ hack for ksh semantics */
 296                                 if (flag == 'V')
 297                                         Eflag = 0;
 298                                 else if (flag == 'E')
 299                                         Vflag = 0;
 300                         }
 301                         return;
 302                 }
 303         error("Illegal option -%c", flag);
 304 }
 305
 306
 307
 308 #ifdef mkinit
 309 INCLUDE "options.h"
 310
 311 SHELLPROC {
 312         int i;
 313
 314         for (i = 0; i < NOPTS; i++)
 315                 optlist[i].val = 0;
 316         optschanged();
 317
 318 }
 319 #endif
 320
 321
 322 /*
 323  * Set the shell parameters.
 324  */
 325
 326 void
 327 setparam(char **argv)
 328 {
 329         char **newparam;
 330         char **ap;
 331         int nparam;
 332
 333         for (nparam = 0 ; argv[nparam] ; nparam++);
 334         ap = newparam = ckmalloc((nparam + 1) * sizeof *ap);
 335         while (*argv) {
 336                 *ap++ = savestr(*argv++);
 337         }
 338         *ap = NULL;
 339         freeparam(&shellparam);
 340         shellparam.malloc = 1;
 341         shellparam.nparam = nparam;
 342         shellparam.p = newparam;
 343         shellparam.optnext = NULL;
 344 }
 345
 346
 347 /*
 348  * Free the list of positional parameters.
 349  */
 350
 351 void
 352 freeparam(volatile struct shparam *param)
 353 {
 354         char **ap;
 355
 356         if (param->malloc) {
 357                 for (ap = param->p ; *ap ; ap++)
 358                         ckfree(*ap);
 359                 ckfree(param->p);
 360         }
 361 }
 362
 363
 364
 365 /*
 366  * The shift builtin command.
 367  */
 368
 369 int
 370 shiftcmd(int argc, char **argv)
 371 {
 372         int n;
 373         char **ap1, **ap2;
 374
 375         n = 1;
 376         if (argc > 1)
 377                 n = number(argv[1]);
 378         if (n > shellparam.nparam)
 379                 return 1;
 380         INTOFF;
 381         shellparam.nparam -= n;
 382         for (ap1 = shellparam.p ; --n >= 0 ; ap1++) {
 383                 if (shellparam.malloc)
 384                         ckfree(*ap1);
 385         }
 386         ap2 = shellparam.p;
 387         while ((*ap2++ = *ap1++) != NULL);
 388         shellparam.optnext = NULL;
 389         INTON;
 390         return 0;
 391 }
 392
 393
 394
 395 /*
 396  * The set command builtin.
 397  */
 398
 399 int
 400 setcmd(int argc, char **argv)
 401 {
 402         if (argc == 1)
 403                 return showvarscmd(argc, argv);
 404         INTOFF;
 405         options(0);
 406         optschanged();
 407         if (*argptr != NULL) {
 408                 setparam(argptr);
 409         }
 410         INTON;
 411         return 0;
 412 }
 413
 414
 415 void
 416 getoptsreset(const char *value)
 417 {
 418         if (number(value) == 1) {
 419                 shellparam.optnext = NULL;
 420                 shellparam.reset = 1;
 421         }
 422 }
 423
 424 /*
 425  * The getopts builtin.  Shellparam.optnext points to the next argument
 426  * to be processed.  Shellparam.optptr points to the next character to
 427  * be processed in the current argument.  If shellparam.optnext is NULL,
 428  * then it's the first time getopts has been called.
 429  */
 430
 431 int
 432 getoptscmd(int argc, char **argv)
 433 {
 434         char **optbase = NULL;
 435
 436         if (argc < 3)
 437                 error("usage: getopts optstring var [arg]");
 438         else if (argc == 3)
 439                 optbase = shellparam.p;
 440         else
 441                 optbase = &argv[3];
 442
 443         if (shellparam.reset == 1) {
 444                 shellparam.optnext = optbase;
 445                 shellparam.optptr = NULL;
 446                 shellparam.reset = 0;
 447         }
 448
 449         return getopts(argv[1], argv[2], optbase, &shellparam.optnext,
 450                        &shellparam.optptr);
 451 }
 452
 453 STATIC int
 454 getopts(char *optstr, char *optvar, char **optfirst, char ***optnext,
 455     char **optp)
 456 {
 457         char *p, *q;
 458         char c = '?';
 459         int done = 0;
 460         int ind = 0;
 461         int err = 0;
 462         char s[10];
 463
 464         if ((p = *optp) == NULL || *p == '\0') {
 465                 /* Current word is done, advance */
 466                 if (*optnext == NULL)
 467                         return 1;
 468                 p = **optnext;
 469                 if (p == NULL || *p != '-' || *++p == '\0') {
 470 atend:
 471                         ind = *optnext - optfirst + 1;
 472                         *optnext = NULL;
 473                         p = NULL;
 474                         done = 1;
 475                         goto out;
 476                 }
 477                 (*optnext)++;
 478                 if (p[0] == '-' && p[1] == '\0')        /* check for "--" */
 479                         goto atend;
 480         }
 481
 482         c = *p++;
 483         for (q = optstr; *q != c; ) {
 484                 if (*q == '\0') {
 485                         if (optstr[0] == ':') {
 486                                 s[0] = c;
 487                                 s[1] = '\0';
 488                                 err |= setvarsafe("OPTARG", s, 0);
 489                         }
 490                         else {
 491                                 out1fmt("Illegal option -%c\n", c);
 492                                 unsetvar("OPTARG");
 493                         }
 494                         c = '?';
 495                         goto bad;
 496                 }
 497                 if (*++q == ':')
 498                         q++;
 499         }
 500
 501         if (*++q == ':') {
 502                 if (*p == '\0' && (p = **optnext) == NULL) {
 503                         if (optstr[0] == ':') {
 504                                 s[0] = c;
 505                                 s[1] = '\0';
 506                                 err |= setvarsafe("OPTARG", s, 0);
 507                                 c = ':';
 508                         }
 509                         else {
 510                                 out1fmt("No arg for -%c option\n", c);
 511                                 unsetvar("OPTARG");
 512                                 c = '?';
 513                         }
 514                         goto bad;
 515                 }
 516
 517                 if (p == **optnext)
 518                         (*optnext)++;
 519                 setvarsafe("OPTARG", p, 0);
 520                 p = NULL;
 521         }
 522         else
 523                 setvarsafe("OPTARG", "", 0);
 524         ind = *optnext - optfirst + 1;
 525         goto out;
 526
 527 bad:
 528         ind = 1;
 529         *optnext = NULL;
 530         p = NULL;
 531 out:
 532         *optp = p;
 533         fmtstr(s, sizeof(s), "%d", ind);
 534         err |= setvarsafe("OPTIND", s, VNOFUNC);
 535         s[0] = c;
 536         s[1] = '\0';
 537         err |= setvarsafe(optvar, s, 0);
 538         if (err) {
 539                 *optnext = NULL;
 540                 *optp = NULL;
 541                 flushall();
 542                 exraise(EXERROR);
 543         }
 544         return done;
 545 }
 546
 547 /*
 548  * XXX - should get rid of.  have all builtins use getopt(3).  the
 549  * library getopt must have the BSD extension static variable "optreset"
 550  * otherwise it can't be used within the shell safely.
 551  *
 552  * Standard option processing (a la getopt) for builtin routines.  The
 553  * only argument that is passed to nextopt is the option string; the
 554  * other arguments are unnecessary.  It return the character, or '\0' on
 555  * end of input.
 556  */
 557
 558 int
 559 nextopt(const char *optstring)
 560 {
 561         const char *p, *q;
 562         char c;
 563
 564         if ((p = optptr) == NULL || *p == '\0') {
 565                 p = *argptr;
 566                 if (p == NULL || *p != '-' || *++p == '\0')
 567                         return '\0';
 568                 argptr++;
 569                 if (p[0] == '-' && p[1] == '\0')        /* check for "--" */
 570                         return '\0';
 571         }
 572         c = *p++;
 573         for (q = optstring ; *q != c ; ) {
 574                 if (*q == '\0')
 575                         error("Illegal option -%c", c);
 576                 if (*++q == ':')
 577                         q++;
 578         }
 579         if (*++q == ':') {
 580                 if (*p == '\0' && (p = *argptr++) == NULL)
 581                         error("No arg for -%c option", c);
 582                 shoptarg = p;
 583                 p = NULL;
 584         }
 585         optptr = p;
 586         return c;
 587 }