sh/options.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1991, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Kenneth Almquist.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #ifndef lint
  36 #if 0
  37 static char sccsid[] = "@(#)options.c   8.2 (Berkeley) 5/4/95";
  38 #endif
  39 #endif /* not lint */
  40 #include <sys/cdefs.h>
  41 __FBSDID("$FreeBSD: head/bin/sh/options.c 326025 2017-11-20 19:49:47Z pfg $");
  42
  43 #include <signal.h>
  44 #include <unistd.h>
  45 #include <stdlib.h>
  46
  47 #include "shell.h"
  48 #define DEFINE_OPTIONS
  49 #include "options.h"
  50 #undef DEFINE_OPTIONS
  51 #include "nodes.h"      /* for other header files */
  52 #include "eval.h"
  53 #include "jobs.h"
  54 #include "input.h"
  55 #include "output.h"
  56 #include "trap.h"
  57 #include "var.h"
  58 #include "memalloc.h"
  59 #include "error.h"
  60 #include "mystring.h"
  61 #include "builtins.h"
  62 #ifndef NO_HISTORY
  63 #include "myhistedit.h"
  64 #endif
  65
  66 char *arg0;                     /* value of $0 */
  67 struct shparam shellparam;      /* current positional parameters */
  68 char **argptr;                  /* argument list for builtin commands */
  69 char *shoptarg;                 /* set by nextopt (like getopt) */
  70 char *nextopt_optptr;           /* used by nextopt */
  71
  72 char *minusc;                   /* argument to -c option */
  73
  74
  75 static void options(int);
  76 static void minus_o(char *, int);
  77 static void setoption(int, int);
  78 static void setoptionbyindex(int, int);
  79 static void setparam(int, char **);
  80 static int getopts(char *, char *, char **, char ***, char **);
  81
  82
  83 /*
  84  * Process the shell command line arguments.
  85  */
  86
  87 void
  88 procargs(int argc, char **argv)
  89 {
  90         int i;
  91         char *scriptname;
  92
  93         argptr = argv;
  94         if (argc > 0)
  95                 argptr++;
  96         for (i = 0; i < NOPTS; i++)
  97                 optval[i] = 2;
  98         privileged = (getuid() != geteuid() || getgid() != getegid());
  99         options(1);
 100         if (*argptr == NULL && minusc == NULL)
 101                 sflag = 1;
 102         if (iflag != 0 && sflag == 1 && isatty(0) && isatty(1)) {
 103                 iflag = 1;
 104                 if (Eflag == 2)
 105                         Eflag = 1;
 106         }
 107         if (mflag == 2)
 108                 mflag = iflag;
 109         for (i = 0; i < NOPTS; i++)
 110                 if (optval[i] == 2)
 111                         optval[i] = 0;
 112         arg0 = argv[0];
 113         if (sflag == 0 && minusc == NULL) {
 114                 scriptname = *argptr++;
 115                 setinputfile(scriptname, 0);
 116                 commandname = arg0 = scriptname;
 117         }
 118         /* POSIX 1003.2: first arg after -c cmd is $0, remainder $1... */
 119         if (argptr && minusc && *argptr)
 120                 arg0 = *argptr++;
 121
 122         shellparam.p = argptr;
 123         shellparam.reset = 1;
 124         /* assert(shellparam.malloc == 0 && shellparam.nparam == 0); */
 125         while (*argptr) {
 126                 shellparam.nparam++;
 127                 argptr++;
 128         }
 129         optschanged();
 130 }
 131
 132
 133 void
 134 optschanged(void)
 135 {
 136         setinteractive();
 137 #ifndef NO_HISTORY
 138         histedit();
 139 #endif
 140         setjobctl(mflag);
 141 }
 142
 143 /*
 144  * Process shell options.  The global variable argptr contains a pointer
 145  * to the argument list; we advance it past the options.
 146  * If cmdline is true, process the shell's argv; otherwise, process arguments
 147  * to the set special builtin.
 148  */
 149
 150 static void
 151 options(int cmdline)
 152 {
 153         char *kp, *p;
 154         int val;
 155         int c;
 156
 157         if (cmdline)
 158                 minusc = NULL;
 159         while ((p = *argptr) != NULL) {
 160                 argptr++;
 161                 if ((c = *p++) == '-') {
 162                         val = 1;
 163                         /* A "-" or  "--" terminates options */
 164                         if (p[0] == '\0')
 165                                 goto end_options1;
 166                         if (p[0] == '-' && p[1] == '\0')
 167                                 goto end_options2;
 168                         /**
 169                          * For the benefit of `#!' lines in shell scripts,
 170                          * treat a string of '-- *#.*' the same as '--'.
 171                          * This is needed so that a script starting with:
 172                          *      #!/bin/sh -- # -*- perl -*-
 173                          * will continue to work after a change is made to
 174                          * kern/imgact_shell.c to NOT token-ize the options
 175                          * specified on a '#!' line.  A bit of a kludge,
 176                          * but that trick is recommended in documentation
 177                          * for some scripting languages, and we might as
 178                          * well continue to support it.
 179                          */
 180                         if (p[0] == '-') {
 181                                 kp = p + 1;
 182                                 while (*kp == ' ' || *kp == '\t')
 183                                         kp++;
 184                                 if (*kp == '#' || *kp == '\0')
 185                                         goto end_options2;
 186                         }
 187                 } else if (c == '+') {
 188                         val = 0;
 189                 } else {
 190                         argptr--;
 191                         break;
 192                 }
 193                 while ((c = *p++) != '\0') {
 194                         if (c == 'c' && cmdline) {
 195                                 char *q;
 196
 197                                 q = *argptr++;
 198                                 if (q == NULL || minusc != NULL)
 199                                         error("Bad -c option");
 200                                 minusc = q;
 201                         } else if (c == 'o') {
 202                                 minus_o(*argptr, val);
 203                                 if (*argptr)
 204                                         argptr++;
 205                         } else
 206                                 setoption(c, val);
 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(0, 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         const unsigned char *on;
 254         size_t len;
 255
 256         if (name == NULL) {
 257                 if (val) {
 258                         /* "Pretty" output. */
 259                         out1str("Current option settings\n");
 260                         for (i = 0, on = optname; i < NOPTS; i++, on += *on + 1)
 261                                 out1fmt("%-16.*s%s\n", *on, on + 1,
 262                                         optval[i] ? "on" : "off");
 263                 } else {
 264                         /* Output suitable for re-input to shell. */
 265                         for (i = 0, on = optname; i < NOPTS; i++, on += *on + 1)
 266                                 out1fmt("%s %co %.*s%s",
 267                                     i % 6 == 0 ? "set" : "",
 268                                     optval[i] ? '-' : '+',
 269                                     *on, on + 1,
 270                                     i % 6 == 5 || i == NOPTS - 1 ? "\n" : "");
 271                 }
 272         } else {
 273                 len = strlen(name);
 274                 for (i = 0, on = optname; i < NOPTS; i++, on += *on + 1)
 275                         if (*on == len && memcmp(on + 1, name, len) == 0) {
 276                                 setoptionbyindex(i, val);
 277                                 return;
 278                         }
 279                 error("Illegal option -o %s", name);
 280         }
 281 }
 282
 283
 284 static void
 285 setoptionbyindex(int idx, int val)
 286 {
 287         if (&optval[idx] == &privileged && !val && privileged) {
 288                 if (setgid(getgid()) == -1)
 289                         error("setgid");
 290                 if (setuid(getuid()) == -1)
 291                         error("setuid");
 292         }
 293         optval[idx] = val;
 294         if (val) {
 295                 /* #%$ hack for ksh semantics */
 296                 if (&optval[idx] == &Vflag)
 297                         Eflag = 0;
 298                 else if (&optval[idx] == &Eflag)
 299                         Vflag = 0;
 300         }
 301 }
 302
 303 static void
 304 setoption(int flag, int val)
 305 {
 306         int i;
 307
 308         for (i = 0; i < NSHORTOPTS; i++)
 309                 if (optletter[i] == flag) {
 310                         setoptionbyindex(i, val);
 311                         return;
 312                 }
 313         error("Illegal option -%c", flag);
 314 }
 315
 316
 317 /*
 318  * Set the shell parameters.
 319  */
 320
 321 static void
 322 setparam(int argc, char **argv)
 323 {
 324         char **newparam;
 325         char **ap;
 326
 327         ap = newparam = ckmalloc((argc + 1) * sizeof *ap);
 328         while (*argv) {
 329                 *ap++ = savestr(*argv++);
 330         }
 331         *ap = NULL;
 332         freeparam(&shellparam);
 333         shellparam.malloc = 1;
 334         shellparam.nparam = argc;
 335         shellparam.p = newparam;
 336         shellparam.optp = NULL;
 337         shellparam.reset = 1;
 338         shellparam.optnext = NULL;
 339 }
 340
 341
 342 /*
 343  * Free the list of positional parameters.
 344  */
 345
 346 void
 347 freeparam(struct shparam *param)
 348 {
 349         char **ap;
 350
 351         if (param->malloc) {
 352                 for (ap = param->p ; *ap ; ap++)
 353                         ckfree(*ap);
 354                 ckfree(param->p);
 355         }
 356         if (param->optp) {
 357                 for (ap = param->optp ; *ap ; ap++)
 358                         ckfree(*ap);
 359                 ckfree(param->optp);
 360         }
 361 }
 362
 363
 364
 365 /*
 366  * The shift builtin command.
 367  */
 368
 369 int
 370 shiftcmd(int argc, char **argv)
 371 {
 372         int i, n;
 373
 374         n = 1;
 375         if (argc > 1)
 376                 n = number(argv[1]);
 377         if (n > shellparam.nparam)
 378                 return 1;
 379         INTOFF;
 380         shellparam.nparam -= n;
 381         if (shellparam.malloc)
 382                 for (i = 0; i < n; i++)
 383                         ckfree(shellparam.p[i]);
 384         memmove(shellparam.p, shellparam.p + n,
 385             (shellparam.nparam + 1) * sizeof(shellparam.p[0]));
 386         shellparam.reset = 1;
 387         INTON;
 388         return 0;
 389 }
 390
 391
 392
 393 /*
 394  * The set builtin command.
 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(argc - (argptr - argv), argptr);
 407         }
 408         INTON;
 409         return 0;
 410 }
 411
 412
 413 void
 414 getoptsreset(const char *value)
 415 {
 416         while (*value == '0')
 417                 value++;
 418         if (strcmp(value, "1") == 0)
 419                 shellparam.reset = 1;
 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, **ap;
 433         int i;
 434
 435         if (argc < 3)
 436                 error("usage: getopts optstring var [arg]");
 437
 438         if (shellparam.reset == 1) {
 439                 INTOFF;
 440                 if (shellparam.optp) {
 441                         for (ap = shellparam.optp ; *ap ; ap++)
 442                                 ckfree(*ap);
 443                         ckfree(shellparam.optp);
 444                         shellparam.optp = NULL;
 445                 }
 446                 if (argc > 3) {
 447                         shellparam.optp = ckmalloc((argc - 2) * sizeof *ap);
 448                         memset(shellparam.optp, '\0', (argc - 2) * sizeof *ap);
 449                         for (i = 0; i < argc - 3; i++)
 450                                 shellparam.optp[i] = savestr(argv[i + 3]);
 451                 }
 452                 INTON;
 453                 optbase = argc == 3 ? shellparam.p : shellparam.optp;
 454                 shellparam.optnext = optbase;
 455                 shellparam.optptr = NULL;
 456                 shellparam.reset = 0;
 457         } else
 458                 optbase = shellparam.optp ? shellparam.optp : shellparam.p;
 459
 460         return getopts(argv[1], argv[2], optbase, &shellparam.optnext,
 461                        &shellparam.optptr);
 462 }
 463
 464 static int
 465 getopts(char *optstr, char *optvar, char **optfirst, char ***optnext,
 466     char **optptr)
 467 {
 468         char *p, *q;
 469         char c = '?';
 470         int done = 0;
 471         int ind = 0;
 472         int err = 0;
 473         char s[10];
 474         const char *newoptarg = NULL;
 475
 476         if ((p = *optptr) == NULL || *p == '\0') {
 477                 /* Current word is done, advance */
 478                 if (*optnext == NULL)
 479                         return 1;
 480                 p = **optnext;
 481                 if (p == NULL || *p != '-' || *++p == '\0') {
 482 atend:
 483                         ind = *optnext - optfirst + 1;
 484                         *optnext = NULL;
 485                         p = NULL;
 486                         done = 1;
 487                         goto out;
 488                 }
 489                 (*optnext)++;
 490                 if (p[0] == '-' && p[1] == '\0')        /* check for "--" */
 491                         goto atend;
 492         }
 493
 494         c = *p++;
 495         for (q = optstr; *q != c; ) {
 496                 if (*q == '\0') {
 497                         if (optstr[0] == ':') {
 498                                 s[0] = c;
 499                                 s[1] = '\0';
 500                                 newoptarg = s;
 501                         }
 502                         else
 503                                 out2fmt_flush("Illegal option -%c\n", c);
 504                         c = '?';
 505                         goto out;
 506                 }
 507                 if (*++q == ':')
 508                         q++;
 509         }
 510
 511         if (*++q == ':') {
 512                 if (*p == '\0' && (p = **optnext) == NULL) {
 513                         if (optstr[0] == ':') {
 514                                 s[0] = c;
 515                                 s[1] = '\0';
 516                                 newoptarg = s;
 517                                 c = ':';
 518                         }
 519                         else {
 520                                 out2fmt_flush("No arg for -%c option\n", c);
 521                                 c = '?';
 522                         }
 523                         goto out;
 524                 }
 525
 526                 if (p == **optnext)
 527                         (*optnext)++;
 528                 newoptarg = p;
 529                 p = NULL;
 530         }
 531
 532 out:
 533         if (*optnext != NULL)
 534                 ind = *optnext - optfirst + 1;
 535         *optptr = p;
 536         if (newoptarg != NULL)
 537                 err |= setvarsafe("OPTARG", newoptarg, 0);
 538         else {
 539                 INTOFF;
 540                 err |= unsetvar("OPTARG");
 541                 INTON;
 542         }
 543         fmtstr(s, sizeof(s), "%d", ind);
 544         err |= setvarsafe("OPTIND", s, VNOFUNC);
 545         s[0] = c;
 546         s[1] = '\0';
 547         err |= setvarsafe(optvar, s, 0);
 548         if (err) {
 549                 *optnext = NULL;
 550                 *optptr = NULL;
 551                 flushall();
 552                 exraise(EXERROR);
 553         }
 554         return done;
 555 }
 556
 557 /*
 558  * Standard option processing (a la getopt) for builtin routines.  The
 559  * only argument that is passed to nextopt is the option string; the
 560  * other arguments are unnecessary.  It returns the option, or '\0' on
 561  * end of input.
 562  */
 563
 564 int
 565 nextopt(const char *optstring)
 566 {
 567         char *p;
 568         const char *q;
 569         char c;
 570
 571         if ((p = nextopt_optptr) == NULL || *p == '\0') {
 572                 p = *argptr;
 573                 if (p == NULL || *p != '-' || *++p == '\0')
 574                         return '\0';
 575                 argptr++;
 576                 if (p[0] == '-' && p[1] == '\0')        /* check for "--" */
 577                         return '\0';
 578         }
 579         c = *p++;
 580         for (q = optstring ; *q != c ; ) {
 581                 if (*q == '\0')
 582                         error("Illegal option -%c", c);
 583                 if (*++q == ':')
 584                         q++;
 585         }
 586         if (*++q == ':') {
 587                 if (*p == '\0' && (p = *argptr++) == NULL)
 588                         error("No arg for -%c option", c);
 589                 shoptarg = p;
 590                 p = NULL;
 591         }
 592         nextopt_optptr = p;
 593         return c;
 594 }