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  * 4. Neither the name of the University nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #ifndef lint
  34 #if 0
  35 static char sccsid[] = "@(#)options.c   8.2 (Berkeley) 5/4/95";
  36 #endif
  37 #endif /* not lint */
  38 #include <sys/cdefs.h>
  39 __FBSDID("$FreeBSD: head/bin/sh/options.c 296577 2016-03-09 21:00:57Z jilles $");
  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 #include "builtins.h"
  60 #ifndef NO_HISTORY
  61 #include "myhistedit.h"
  62 #endif
  63
  64 char *arg0;                     /* value of $0 */
  65 struct shparam shellparam;      /* current positional parameters */
  66 char **argptr;                  /* argument list for builtin commands */
  67 char *shoptarg;                 /* set by nextopt (like getopt) */
  68 char *nextopt_optptr;           /* used by nextopt */
  69
  70 char *minusc;                   /* argument to -c option */
  71
  72
  73 static void options(int);
  74 static void minus_o(char *, int);
  75 static void setoption(int, int);
  76 static void setoptionbyindex(int, int);
  77 static void setparam(int, char **);
  78 static int getopts(char *, char *, char **, char ***, char **);
  79
  80
  81 /*
  82  * Process the shell command line arguments.
  83  */
  84
  85 void
  86 procargs(int argc, char **argv)
  87 {
  88         int i;
  89         char *scriptname;
  90
  91         argptr = argv;
  92         if (argc > 0)
  93                 argptr++;
  94         for (i = 0; i < NOPTS; i++)
  95                 optval[i] = 2;
  96         privileged = (getuid() != geteuid() || getgid() != getegid());
  97         options(1);
  98         if (*argptr == NULL && minusc == NULL)
  99                 sflag = 1;
 100         if (iflag != 0 && sflag == 1 && isatty(0) && isatty(1)) {
 101                 iflag = 1;
 102                 if (Eflag == 2)
 103                         Eflag = 1;
 104         }
 105         if (mflag == 2)
 106                 mflag = iflag;
 107         for (i = 0; i < NOPTS; i++)
 108                 if (optval[i] == 2)
 109                         optval[i] = 0;
 110         arg0 = argv[0];
 111         if (sflag == 0 && minusc == NULL) {
 112                 scriptname = *argptr++;
 113                 setinputfile(scriptname, 0);
 114                 commandname = arg0 = scriptname;
 115         }
 116         /* POSIX 1003.2: first arg after -c cmd is $0, remainder $1... */
 117         if (argptr && minusc && *argptr)
 118                 arg0 = *argptr++;
 119
 120         shellparam.p = argptr;
 121         shellparam.reset = 1;
 122         /* assert(shellparam.malloc == 0 && shellparam.nparam == 0); */
 123         while (*argptr) {
 124                 shellparam.nparam++;
 125                 argptr++;
 126         }
 127         optschanged();
 128 }
 129
 130
 131 void
 132 optschanged(void)
 133 {
 134         setinteractive(iflag);
 135 #ifndef NO_HISTORY
 136         histedit();
 137 #endif
 138         setjobctl(mflag);
 139 }
 140
 141 /*
 142  * Process shell options.  The global variable argptr contains a pointer
 143  * to the argument list; we advance it past the options.
 144  */
 145
 146 static void
 147 options(int cmdline)
 148 {
 149         char *kp, *p;
 150         int val;
 151         int c;
 152
 153         if (cmdline)
 154                 minusc = NULL;
 155         while ((p = *argptr) != NULL) {
 156                 argptr++;
 157                 if ((c = *p++) == '-') {
 158                         val = 1;
 159                         /* A "-" or  "--" terminates options */
 160                         if (p[0] == '\0')
 161                                 goto end_options1;
 162                         if (p[0] == '-' && p[1] == '\0')
 163                                 goto end_options2;
 164                         /**
 165                          * For the benefit of `#!' lines in shell scripts,
 166                          * treat a string of '-- *#.*' the same as '--'.
 167                          * This is needed so that a script starting with:
 168                          *      #!/bin/sh -- # -*- perl -*-
 169                          * will continue to work after a change is made to
 170                          * kern/imgact_shell.c to NOT token-ize the options
 171                          * specified on a '#!' line.  A bit of a kludge,
 172                          * but that trick is recommended in documentation
 173                          * for some scripting languages, and we might as
 174                          * well continue to support it.
 175                          */
 176                         if (p[0] == '-') {
 177                                 kp = p + 1;
 178                                 while (*kp == ' ' || *kp == '\t')
 179                                         kp++;
 180                                 if (*kp == '#' || *kp == '\0')
 181                                         goto end_options2;
 182                         }
 183                 } else if (c == '+') {
 184                         val = 0;
 185                 } else {
 186                         argptr--;
 187                         break;
 188                 }
 189                 while ((c = *p++) != '\0') {
 190                         if (c == 'c' && cmdline) {
 191                                 char *q;
 192 #ifdef NOHACK   /* removing this code allows sh -ce 'foo' for compat */
 193                                 if (*p == '\0')
 194 #endif
 195                                         q = *argptr++;
 196                                 if (q == NULL || minusc != NULL)
 197                                         error("Bad -c option");
 198                                 minusc = q;
 199 #ifdef NOHACK
 200                                 break;
 201 #endif
 202                         } else if (c == 'o') {
 203                                 minus_o(*argptr, val);
 204                                 if (*argptr)
 205                                         argptr++;
 206                         } else
 207                                 setoption(c, val);
 208                 }
 209         }
 210         return;
 211
 212         /* When processing `set', a single "-" means turn off -x and -v */
 213 end_options1:
 214         if (!cmdline) {
 215                 xflag = vflag = 0;
 216                 return;
 217         }
 218
 219         /*
 220          * When processing `set', a "--" means the remaining arguments
 221          * replace the positional parameters in the active shell.  If
 222          * there are no remaining options, then all the positional
 223          * parameters are cleared (equivalent to doing ``shift $#'').
 224          */
 225 end_options2:
 226         if (!cmdline) {
 227                 if (*argptr == NULL)
 228                         setparam(0, argptr);
 229                 return;
 230         }
 231
 232         /*
 233          * At this point we are processing options given to 'sh' on a command
 234          * line.  If an end-of-options marker ("-" or "--") is followed by an
 235          * arg of "#", then skip over all remaining arguments.  Some scripting
 236          * languages (e.g.: perl) document that /bin/sh will implement this
 237          * behavior, and they recommend that users take advantage of it to
 238          * solve certain issues that can come up when writing a perl script.
 239          * Yes, this feature is in /bin/sh to help users write perl scripts.
 240          */
 241         p = *argptr;
 242         if (p != NULL && p[0] == '#' && p[1] == '\0') {
 243                 while (*argptr != NULL)
 244                         argptr++;
 245                 /* We need to keep the final argument */
 246                 argptr--;
 247         }
 248 }
 249
 250 static void
 251 minus_o(char *name, int val)
 252 {
 253         int i;
 254         const unsigned char *on;
 255         size_t len;
 256
 257         if (name == NULL) {
 258                 if (val) {
 259                         /* "Pretty" output. */
 260                         out1str("Current option settings\n");
 261                         for (i = 0, on = optname; i < NOPTS; i++, on += *on + 1)
 262                                 out1fmt("%-16.*s%s\n", *on, on + 1,
 263                                         optval[i] ? "on" : "off");
 264                 } else {
 265                         /* Output suitable for re-input to shell. */
 266                         for (i = 0, on = optname; i < NOPTS; i++, on += *on + 1)
 267                                 out1fmt("%s %co %.*s%s",
 268                                     i % 6 == 0 ? "set" : "",
 269                                     optval[i] ? '-' : '+',
 270                                     *on, on + 1,
 271                                     i % 6 == 5 || i == NOPTS - 1 ? "\n" : "");
 272                 }
 273         } else {
 274                 len = strlen(name);
 275                 for (i = 0, on = optname; i < NOPTS; i++, on += *on + 1)
 276                         if (*on == len && memcmp(on + 1, name, len) == 0) {
 277                                 setoptionbyindex(i, val);
 278                                 return;
 279                         }
 280                 error("Illegal option -o %s", name);
 281         }
 282 }
 283
 284
 285 static void
 286 setoptionbyindex(int idx, int val)
 287 {
 288         if (&optval[idx] == &privileged && !val && privileged) {
 289                 if (setgid(getgid()) == -1)
 290                         error("setgid");
 291                 if (setuid(getuid()) == -1)
 292                         error("setuid");
 293         }
 294         optval[idx] = val;
 295         if (val) {
 296                 /* #%$ hack for ksh semantics */
 297                 if (&optval[idx] == &Vflag)
 298                         Eflag = 0;
 299                 else if (&optval[idx] == &Eflag)
 300                         Vflag = 0;
 301         }
 302 }
 303
 304 static void
 305 setoption(int flag, int val)
 306 {
 307         int i;
 308
 309         for (i = 0; i < NSHORTOPTS; i++)
 310                 if (optletter[i] == flag) {
 311                         setoptionbyindex(i, val);
 312                         return;
 313                 }
 314         error("Illegal option -%c", flag);
 315 }
 316
 317
 318 /*
 319  * Set the shell parameters.
 320  */
 321
 322 static void
 323 setparam(int argc, char **argv)
 324 {
 325         char **newparam;
 326         char **ap;
 327
 328         ap = newparam = ckmalloc((argc + 1) * sizeof *ap);
 329         while (*argv) {
 330                 *ap++ = savestr(*argv++);
 331         }
 332         *ap = NULL;
 333         freeparam(&shellparam);
 334         shellparam.malloc = 1;
 335         shellparam.nparam = argc;
 336         shellparam.p = newparam;
 337         shellparam.optp = NULL;
 338         shellparam.reset = 1;
 339         shellparam.optnext = NULL;
 340 }
 341
 342
 343 /*
 344  * Free the list of positional parameters.
 345  */
 346
 347 void
 348 freeparam(struct shparam *param)
 349 {
 350         char **ap;
 351
 352         if (param->malloc) {
 353                 for (ap = param->p ; *ap ; ap++)
 354                         ckfree(*ap);
 355                 ckfree(param->p);
 356         }
 357         if (param->optp) {
 358                 for (ap = param->optp ; *ap ; ap++)
 359                         ckfree(*ap);
 360                 ckfree(param->optp);
 361         }
 362 }
 363
 364
 365
 366 /*
 367  * The shift builtin command.
 368  */
 369
 370 int
 371 shiftcmd(int argc, char **argv)
 372 {
 373         int i, n;
 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         if (shellparam.malloc)
 383                 for (i = 0; i < n; i++)
 384                         ckfree(shellparam.p[i]);
 385         memmove(shellparam.p, shellparam.p + n,
 386             (shellparam.nparam + 1) * sizeof(shellparam.p[0]));
 387         shellparam.reset = 1;
 388         INTON;
 389         return 0;
 390 }
 391
 392
 393
 394 /*
 395  * The set command builtin.
 396  */
 397
 398 int
 399 setcmd(int argc, char **argv)
 400 {
 401         if (argc == 1)
 402                 return showvarscmd(argc, argv);
 403         INTOFF;
 404         options(0);
 405         optschanged();
 406         if (*argptr != NULL) {
 407                 setparam(argc - (argptr - argv), argptr);
 408         }
 409         INTON;
 410         return 0;
 411 }
 412
 413
 414 void
 415 getoptsreset(const char *value)
 416 {
 417         while (*value == '0')
 418                 value++;
 419         if (strcmp(value, "1") == 0)
 420                 shellparam.reset = 1;
 421 }
 422
 423 /*
 424  * The getopts builtin.  Shellparam.optnext points to the next argument
 425  * to be processed.  Shellparam.optptr points to the next character to
 426  * be processed in the current argument.  If shellparam.optnext is NULL,
 427  * then it's the first time getopts has been called.
 428  */
 429
 430 int
 431 getoptscmd(int argc, char **argv)
 432 {
 433         char **optbase = NULL, **ap;
 434         int i;
 435
 436         if (argc < 3)
 437                 error("usage: getopts optstring var [arg]");
 438
 439         if (shellparam.reset == 1) {
 440                 INTOFF;
 441                 if (shellparam.optp) {
 442                         for (ap = shellparam.optp ; *ap ; ap++)
 443                                 ckfree(*ap);
 444                         ckfree(shellparam.optp);
 445                         shellparam.optp = NULL;
 446                 }
 447                 if (argc > 3) {
 448                         shellparam.optp = ckmalloc((argc - 2) * sizeof *ap);
 449                         memset(shellparam.optp, '\0', (argc - 2) * sizeof *ap);
 450                         for (i = 0; i < argc - 3; i++)
 451                                 shellparam.optp[i] = savestr(argv[i + 3]);
 452                 }
 453                 INTON;
 454                 optbase = argc == 3 ? shellparam.p : shellparam.optp;
 455                 shellparam.optnext = optbase;
 456                 shellparam.optptr = NULL;
 457                 shellparam.reset = 0;
 458         } else
 459                 optbase = shellparam.optp ? shellparam.optp : shellparam.p;
 460
 461         return getopts(argv[1], argv[2], optbase, &shellparam.optnext,
 462                        &shellparam.optptr);
 463 }
 464
 465 static int
 466 getopts(char *optstr, char *optvar, char **optfirst, char ***optnext,
 467     char **optptr)
 468 {
 469         char *p, *q;
 470         char c = '?';
 471         int done = 0;
 472         int ind = 0;
 473         int err = 0;
 474         char s[10];
 475         const char *newoptarg = NULL;
 476
 477         if ((p = *optptr) == NULL || *p == '\0') {
 478                 /* Current word is done, advance */
 479                 if (*optnext == NULL)
 480                         return 1;
 481                 p = **optnext;
 482                 if (p == NULL || *p != '-' || *++p == '\0') {
 483 atend:
 484                         ind = *optnext - optfirst + 1;
 485                         *optnext = NULL;
 486                         p = NULL;
 487                         done = 1;
 488                         goto out;
 489                 }
 490                 (*optnext)++;
 491                 if (p[0] == '-' && p[1] == '\0')        /* check for "--" */
 492                         goto atend;
 493         }
 494
 495         c = *p++;
 496         for (q = optstr; *q != c; ) {
 497                 if (*q == '\0') {
 498                         if (optstr[0] == ':') {
 499                                 s[0] = c;
 500                                 s[1] = '\0';
 501                                 newoptarg = s;
 502                         }
 503                         else
 504                                 out2fmt_flush("Illegal option -%c\n", c);
 505                         c = '?';
 506                         goto out;
 507                 }
 508                 if (*++q == ':')
 509                         q++;
 510         }
 511
 512         if (*++q == ':') {
 513                 if (*p == '\0' && (p = **optnext) == NULL) {
 514                         if (optstr[0] == ':') {
 515                                 s[0] = c;
 516                                 s[1] = '\0';
 517                                 newoptarg = s;
 518                                 c = ':';
 519                         }
 520                         else {
 521                                 out2fmt_flush("No arg for -%c option\n", c);
 522                                 c = '?';
 523                         }
 524                         goto out;
 525                 }
 526
 527                 if (p == **optnext)
 528                         (*optnext)++;
 529                 newoptarg = p;
 530                 p = NULL;
 531         }
 532
 533 out:
 534         if (*optnext != NULL)
 535                 ind = *optnext - optfirst + 1;
 536         *optptr = p;
 537         if (newoptarg != NULL)
 538                 err |= setvarsafe("OPTARG", newoptarg, 0);
 539         else {
 540                 INTOFF;
 541                 err |= unsetvar("OPTARG");
 542                 INTON;
 543         }
 544         fmtstr(s, sizeof(s), "%d", ind);
 545         err |= setvarsafe("OPTIND", s, VNOFUNC);
 546         s[0] = c;
 547         s[1] = '\0';
 548         err |= setvarsafe(optvar, s, 0);
 549         if (err) {
 550                 *optnext = NULL;
 551                 *optptr = NULL;
 552                 flushall();
 553                 exraise(EXERROR);
 554         }
 555         return done;
 556 }
 557
 558 /*
 559  * Standard option processing (a la getopt) for builtin routines.  The
 560  * only argument that is passed to nextopt is the option string; the
 561  * other arguments are unnecessary.  It return the character, or '\0' on
 562  * end of input.
 563  */
 564
 565 int
 566 nextopt(const char *optstring)
 567 {
 568         char *p;
 569         const char *q;
 570         char c;
 571
 572         if ((p = nextopt_optptr) == NULL || *p == '\0') {
 573                 p = *argptr;
 574                 if (p == NULL || *p != '-' || *++p == '\0')
 575                         return '\0';
 576                 argptr++;
 577                 if (p[0] == '-' && p[1] == '\0')        /* check for "--" */
 578                         return '\0';
 579         }
 580         c = *p++;
 581         for (q = optstring ; *q != c ; ) {
 582                 if (*q == '\0')
 583                         error("Illegal option -%c", c);
 584                 if (*++q == ':')
 585                         q++;
 586         }
 587         if (*++q == ':') {
 588                 if (*p == '\0' && (p = *argptr++) == NULL)
 589                         error("No arg for -%c option", c);
 590                 shoptarg = p;
 591                 p = NULL;
 592         }
 593         nextopt_optptr = p;
 594         return c;
 595 }