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         for (i = 0; i < NOPTS; i++)
 101                 if (optlist[i].val == 2)
 102                         optlist[i].val = 0;
 103         arg0 = argv[0];
 104         if (sflag == 0 && minusc == NULL) {
 105                 commandname = arg0 = *argptr++;
 106                 setinputfile(commandname, 0);
 107         }
 108         /* POSIX 1003.2: first arg after -c cmd is $0, remainder $1... */
 109         if (argptr && minusc && *argptr)
 110                 arg0 = *argptr++;
 111
 112         shellparam.p = argptr;
 113         shellparam.reset = 1;
 114         /* assert(shellparam.malloc == 0 && shellparam.nparam == 0); */
 115         while (*argptr) {
 116                 shellparam.nparam++;
 117                 argptr++;
 118         }
 119         optschanged();
 120 }
 121
 122
 123 void
 124 optschanged(void)
 125 {
 126         setinteractive(iflag);
 127 #ifndef NO_HISTORY
 128         histedit();
 129 #endif
 130         setjobctl(mflag);
 131 }
 132
 133 /*
 134  * Process shell options.  The global variable argptr contains a pointer
 135  * to the argument list; we advance it past the options.
 136  */
 137
 138 STATIC void
 139 options(int cmdline)
 140 {
 141         char *kp, *p;
 142         int val;
 143         int c;
 144
 145         if (cmdline)
 146                 minusc = NULL;
 147         while ((p = *argptr) != NULL) {
 148                 argptr++;
 149                 if ((c = *p++) == '-') {
 150                         val = 1;
 151                         /* A "-" or  "--" terminates options */
 152                         if (p[0] == '\0')
 153                                 goto end_options1;
 154                         if (p[0] == '-' && p[1] == '\0')
 155                                 goto end_options2;
 156                         /**
 157                          * For the benefit of `#!' lines in shell scripts,
 158                          * treat a string of '-- *#.*' the same as '--'.
 159                          * This is needed so that a script starting with:
 160                          *      #!/bin/sh -- # -*- perl -*-
 161                          * will continue to work after a change is made to
 162                          * kern/imgact_shell.c to NOT token-ize the options
 163                          * specified on a '#!' line.  A bit of a kludge,
 164                          * but that trick is recommended in documentation
 165                          * for some scripting languages, and we might as
 166                          * well continue to support it.
 167                          */
 168                         if (p[0] == '-') {
 169                                 kp = p + 1;
 170                                 while (*kp == ' ' || *kp == '\t')
 171                                         kp++;
 172                                 if (*kp == '#' || *kp == '\0')
 173                                         goto end_options2;
 174                         }
 175                 } else if (c == '+') {
 176                         val = 0;
 177                 } else {
 178                         argptr--;
 179                         break;
 180                 }
 181                 while ((c = *p++) != '\0') {
 182                         if (c == 'c' && cmdline) {
 183                                 char *q;
 184 #ifdef NOHACK   /* removing this code allows sh -ce 'foo' for compat */
 185                                 if (*p == '\0')
 186 #endif
 187                                         q = *argptr++;
 188                                 if (q == NULL || minusc != NULL)
 189                                         error("Bad -c option");
 190                                 minusc = q;
 191 #ifdef NOHACK
 192                                 break;
 193 #endif
 194                         } else if (c == 'o') {
 195                                 minus_o(*argptr, val);
 196                                 if (*argptr)
 197                                         argptr++;
 198                         } else {
 199                                 if (c == 'p' && !val && privileged) {
 200                                         setuid(getuid());
 201                                         setgid(getgid());
 202                                 }
 203                                 setoption(c, val);
 204                         }
 205                 }
 206         }
 207         return;
 208
 209         /* When processing `set', a single "-" means turn off -x and -v */
 210 end_options1:
 211         if (!cmdline) {
 212                 xflag = vflag = 0;
 213                 return;
 214         }
 215
 216         /*
 217          * When processing `set', a "--" means the remaining arguments
 218          * replace the positional parameters in the active shell.  If
 219          * there are no remaining options, then all the positional
 220          * parameters are cleared (equivalent to doing ``shift $#'').
 221          */
 222 end_options2:
 223         if (!cmdline) {
 224                 if (*argptr == NULL)
 225                         setparam(argptr);
 226                 return;
 227         }
 228
 229         /*
 230          * At this point we are processing options given to 'sh' on a command
 231          * line.  If an end-of-options marker ("-" or "--") is followed by an
 232          * arg of "#", then skip over all remaining arguments.  Some scripting
 233          * languages (e.g.: perl) document that /bin/sh will implement this
 234          * behavior, and they recommend that users take advantage of it to
 235          * solve certain issues that can come up when writing a perl script.
 236          * Yes, this feature is in /bin/sh to help users write perl scripts.
 237          */
 238         p = *argptr;
 239         if (p != NULL && p[0] == '#' && p[1] == '\0') {
 240                 while (*argptr != NULL)
 241                         argptr++;
 242                 /* We need to keep the final argument */
 243                 argptr--;
 244         }
 245 }
 246
 247 STATIC void
 248 minus_o(char *name, int val)
 249 {
 250         int i;
 251
 252         if (name == NULL) {
 253                 if (val) {
 254                         /* "Pretty" output. */
 255                         out1str("Current option settings\n");
 256                         for (i = 0; i < NOPTS; i++)
 257                                 out1fmt("%-16s%s\n", optlist[i].name,
 258                                         optlist[i].val ? "on" : "off");
 259                 } else {
 260                         /* Output suitable for re-input to shell. */
 261                         for (i = 0; i < NOPTS; i++) {
 262                                 if (i % 6 == 0)
 263                                         out1str(i == 0 ? "set" : "\nset");
 264                                 out1fmt(" %co %s", optlist[i].val ? '-' : '+',
 265                                         optlist[i].name);
 266                         }
 267                         out1c('\n');
 268                 }
 269         } else {
 270                 for (i = 0; i < NOPTS; i++)
 271                         if (equal(name, optlist[i].name)) {
 272                                 if (!val && privileged && equal(name, "privileged")) {
 273                                         setuid(getuid());
 274                                         setgid(getgid());
 275                                 }
 276                                 setoption(optlist[i].letter, val);
 277                                 return;
 278                         }
 279                 error("Illegal option -o %s", name);
 280         }
 281 }
 282
 283
 284 STATIC void
 285 setoption(int flag, int val)
 286 {
 287         int i;
 288
 289         for (i = 0; i < NOPTS; i++)
 290                 if (optlist[i].letter == flag) {
 291                         optlist[i].val = val;
 292                         if (val) {
 293                                 /* #%$ hack for ksh semantics */
 294                                 if (flag == 'V')
 295                                         Eflag = 0;
 296                                 else if (flag == 'E')
 297                                         Vflag = 0;
 298                         }
 299                         return;
 300                 }
 301         error("Illegal option -%c", flag);
 302 }
 303
 304
 305
 306 #ifdef mkinit
 307 INCLUDE "options.h"
 308
 309 SHELLPROC {
 310         int i;
 311
 312         for (i = 0; i < NOPTS; i++)
 313                 optlist[i].val = 0;
 314         optschanged();
 315
 316 }
 317 #endif
 318
 319
 320 /*
 321  * Set the shell parameters.
 322  */
 323
 324 void
 325 setparam(char **argv)
 326 {
 327         char **newparam;
 328         char **ap;
 329         int nparam;
 330
 331         for (nparam = 0 ; argv[nparam] ; nparam++);
 332         ap = newparam = ckmalloc((nparam + 1) * sizeof *ap);
 333         while (*argv) {
 334                 *ap++ = savestr(*argv++);
 335         }
 336         *ap = NULL;
 337         freeparam(&shellparam);
 338         shellparam.malloc = 1;
 339         shellparam.nparam = nparam;
 340         shellparam.p = newparam;
 341         shellparam.optnext = NULL;
 342 }
 343
 344
 345 /*
 346  * Free the list of positional parameters.
 347  */
 348
 349 void
 350 freeparam(volatile struct shparam *param)
 351 {
 352         char **ap;
 353
 354         if (param->malloc) {
 355                 for (ap = param->p ; *ap ; ap++)
 356                         ckfree(*ap);
 357                 ckfree(param->p);
 358         }
 359 }
 360
 361
 362
 363 /*
 364  * The shift builtin command.
 365  */
 366
 367 int
 368 shiftcmd(int argc, char **argv)
 369 {
 370         int n;
 371         char **ap1, **ap2;
 372
 373         n = 1;
 374         if (argc > 1)
 375                 n = number(argv[1]);
 376         if (n > shellparam.nparam)
 377                 return 1;
 378         INTOFF;
 379         shellparam.nparam -= n;
 380         for (ap1 = shellparam.p ; --n >= 0 ; ap1++) {
 381                 if (shellparam.malloc)
 382                         ckfree(*ap1);
 383         }
 384         ap2 = shellparam.p;
 385         while ((*ap2++ = *ap1++) != NULL);
 386         shellparam.optnext = NULL;
 387         INTON;
 388         return 0;
 389 }
 390
 391
 392
 393 /*
 394  * The set command builtin.
 395  */
 396
 397 int
 398 setcmd(int argc, char **argv)
 399 {
 400         if (argc == 1)
 401                 return showvarscmd(argc, argv);
 402         INTOFF;
 403         options(0);
 404         optschanged();
 405         if (*argptr != NULL) {
 406                 setparam(argptr);
 407         }
 408         INTON;
 409         return 0;
 410 }
 411
 412
 413 void
 414 getoptsreset(const char *value)
 415 {
 416         if (number(value) == 1) {
 417                 shellparam.optnext = NULL;
 418                 shellparam.reset = 1;
 419         }
 420 }
 421
 422 /*
 423  * The getopts builtin.  Shellparam.optnext points to the next argument
 424  * to be processed.  Shellparam.optptr points to the next character to
 425  * be processed in the current argument.  If shellparam.optnext is NULL,
 426  * then it's the first time getopts has been called.
 427  */
 428
 429 int
 430 getoptscmd(int argc, char **argv)
 431 {
 432         char **optbase = NULL;
 433
 434         if (argc < 3)
 435                 error("usage: getopts optstring var [arg]");
 436         else if (argc == 3)
 437                 optbase = shellparam.p;
 438         else
 439                 optbase = &argv[3];
 440
 441         if (shellparam.reset == 1) {
 442                 shellparam.optnext = optbase;
 443                 shellparam.optptr = NULL;
 444                 shellparam.reset = 0;
 445         }
 446
 447         return getopts(argv[1], argv[2], optbase, &shellparam.optnext,
 448                        &shellparam.optptr);
 449 }
 450
 451 STATIC int
 452 getopts(char *optstr, char *optvar, char **optfirst, char ***optnext,
 453     char **optp)
 454 {
 455         char *p, *q;
 456         char c = '?';
 457         int done = 0;
 458         int ind = 0;
 459         int err = 0;
 460         char s[10];
 461
 462         if ((p = *optp) == NULL || *p == '\0') {
 463                 /* Current word is done, advance */
 464                 if (*optnext == NULL)
 465                         return 1;
 466                 p = **optnext;
 467                 if (p == NULL || *p != '-' || *++p == '\0') {
 468 atend:
 469                         ind = *optnext - optfirst + 1;
 470                         *optnext = NULL;
 471                         p = NULL;
 472                         done = 1;
 473                         goto out;
 474                 }
 475                 (*optnext)++;
 476                 if (p[0] == '-' && p[1] == '\0')        /* check for "--" */
 477                         goto atend;
 478         }
 479
 480         c = *p++;
 481         for (q = optstr; *q != c; ) {
 482                 if (*q == '\0') {
 483                         if (optstr[0] == ':') {
 484                                 s[0] = c;
 485                                 s[1] = '\0';
 486                                 err |= setvarsafe("OPTARG", s, 0);
 487                         }
 488                         else {
 489                                 out1fmt("Illegal option -%c\n", c);
 490                                 unsetvar("OPTARG");
 491                         }
 492                         c = '?';
 493                         goto bad;
 494                 }
 495                 if (*++q == ':')
 496                         q++;
 497         }
 498
 499         if (*++q == ':') {
 500                 if (*p == '\0' && (p = **optnext) == NULL) {
 501                         if (optstr[0] == ':') {
 502                                 s[0] = c;
 503                                 s[1] = '\0';
 504                                 err |= setvarsafe("OPTARG", s, 0);
 505                                 c = ':';
 506                         }
 507                         else {
 508                                 out1fmt("No arg for -%c option\n", c);
 509                                 unsetvar("OPTARG");
 510                                 c = '?';
 511                         }
 512                         goto bad;
 513                 }
 514
 515                 if (p == **optnext)
 516                         (*optnext)++;
 517                 setvarsafe("OPTARG", p, 0);
 518                 p = NULL;
 519         }
 520         else
 521                 setvarsafe("OPTARG", "", 0);
 522         ind = *optnext - optfirst + 1;
 523         goto out;
 524
 525 bad:
 526         ind = 1;
 527         *optnext = NULL;
 528         p = NULL;
 529 out:
 530         *optp = p;
 531         fmtstr(s, sizeof(s), "%d", ind);
 532         err |= setvarsafe("OPTIND", s, VNOFUNC);
 533         s[0] = c;
 534         s[1] = '\0';
 535         err |= setvarsafe(optvar, s, 0);
 536         if (err) {
 537                 *optnext = NULL;
 538                 *optp = NULL;
 539                 flushall();
 540                 exraise(EXERROR);
 541         }
 542         return done;
 543 }
 544
 545 /*
 546  * XXX - should get rid of.  have all builtins use getopt(3).  the
 547  * library getopt must have the BSD extension static variable "optreset"
 548  * otherwise it can't be used within the shell safely.
 549  *
 550  * Standard option processing (a la getopt) for builtin routines.  The
 551  * only argument that is passed to nextopt is the option string; the
 552  * other arguments are unnecessary.  It return the character, or '\0' on
 553  * end of input.
 554  */
 555
 556 int
 557 nextopt(const char *optstring)
 558 {
 559         const char *p, *q;
 560         char c;
 561
 562         if ((p = optptr) == NULL || *p == '\0') {
 563                 p = *argptr;
 564                 if (p == NULL || *p != '-' || *++p == '\0')
 565                         return '\0';
 566                 argptr++;
 567                 if (p[0] == '-' && p[1] == '\0')        /* check for "--" */
 568                         return '\0';
 569         }
 570         c = *p++;
 571         for (q = optstring ; *q != c ; ) {
 572                 if (*q == '\0')
 573                         error("Illegal option -%c", c);
 574                 if (*++q == ':')
 575                         q++;
 576         }
 577         if (*++q == ':') {
 578                 if (*p == '\0' && (p = *argptr++) == NULL)
 579                         error("No arg for -%c option", c);
 580                 shoptarg = p;
 581                 p = NULL;
 582         }
 583         optptr = p;
 584         return c;
 585 }