The Android Open Source Project | dd7bc33 | 2009-03-03 19:32:55 -0800 | [diff] [blame] | 1 | /* $NetBSD: var.c,v 1.36 2004/10/06 10:23:43 enami Exp $ */ |
| 2 | |
| 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 | #include <sys/cdefs.h> |
| 36 | #ifndef lint |
| 37 | #if 0 |
| 38 | static char sccsid[] = "@(#)var.c 8.3 (Berkeley) 5/4/95"; |
| 39 | #else |
| 40 | __RCSID("$NetBSD: var.c,v 1.36 2004/10/06 10:23:43 enami Exp $"); |
| 41 | #endif |
| 42 | #endif /* not lint */ |
| 43 | |
| 44 | #include <unistd.h> |
| 45 | #include <stdlib.h> |
| 46 | #include <paths.h> |
| 47 | |
| 48 | /* |
| 49 | * Shell variables. |
| 50 | */ |
| 51 | |
| 52 | #include "shell.h" |
| 53 | #include "output.h" |
| 54 | #include "expand.h" |
| 55 | #include "nodes.h" /* for other headers */ |
| 56 | #include "eval.h" /* defines cmdenviron */ |
| 57 | #include "exec.h" |
| 58 | #include "syntax.h" |
| 59 | #include "options.h" |
| 60 | #include "var.h" |
| 61 | #include "memalloc.h" |
| 62 | #include "error.h" |
| 63 | #include "mystring.h" |
| 64 | #include "parser.h" |
| 65 | #include "show.h" |
| 66 | #ifndef SMALL |
| 67 | #include "myhistedit.h" |
| 68 | #endif |
| 69 | |
| 70 | #ifdef SMALL |
| 71 | #define VTABSIZE 39 |
| 72 | #else |
| 73 | #define VTABSIZE 517 |
| 74 | #endif |
| 75 | |
| 76 | |
| 77 | struct varinit { |
| 78 | struct var *var; |
| 79 | int flags; |
| 80 | const char *text; |
| 81 | void (*func)(const char *); |
| 82 | }; |
| 83 | |
| 84 | |
| 85 | #if ATTY |
| 86 | struct var vatty; |
| 87 | #endif |
| 88 | #ifdef WITH_HISTORY |
| 89 | struct var vhistsize; |
| 90 | struct var vterm; |
| 91 | #endif |
| 92 | struct var vifs; |
| 93 | struct var vmpath; |
| 94 | struct var vpath; |
| 95 | struct var vps1; |
| 96 | struct var vps2; |
| 97 | struct var vps4; |
| 98 | struct var vvers; |
| 99 | struct var voptind; |
| 100 | |
| 101 | const struct varinit varinit[] = { |
| 102 | #if ATTY |
| 103 | { &vatty, VSTRFIXED|VTEXTFIXED|VUNSET, "ATTY=", |
| 104 | NULL }, |
| 105 | #endif |
| 106 | #ifdef WITH_HISTORY |
| 107 | { &vhistsize, VSTRFIXED|VTEXTFIXED|VUNSET, "HISTSIZE=", |
| 108 | sethistsize }, |
| 109 | #endif |
| 110 | { &vifs, VSTRFIXED|VTEXTFIXED, "IFS= \t\n", |
| 111 | NULL }, |
| 112 | { &vmpath, VSTRFIXED|VTEXTFIXED|VUNSET, "MAILPATH=", |
| 113 | NULL }, |
| 114 | { &vpath, VSTRFIXED|VTEXTFIXED, "PATH=" _PATH_DEFPATH, |
| 115 | changepath }, |
| 116 | /* |
| 117 | * vps1 depends on uid |
| 118 | */ |
| 119 | { &vps2, VSTRFIXED|VTEXTFIXED, "PS2=> ", |
| 120 | NULL }, |
| 121 | { &vps4, VSTRFIXED|VTEXTFIXED, "PS4=+ ", |
| 122 | NULL }, |
| 123 | #ifdef WITH_HISTORY |
| 124 | { &vterm, VSTRFIXED|VTEXTFIXED|VUNSET, "TERM=", |
| 125 | setterm }, |
| 126 | #endif |
| 127 | { &voptind, VSTRFIXED|VTEXTFIXED|VNOFUNC, "OPTIND=1", |
| 128 | getoptsreset }, |
| 129 | { NULL, 0, NULL, |
| 130 | NULL } |
| 131 | }; |
| 132 | |
| 133 | struct var *vartab[VTABSIZE]; |
| 134 | |
| 135 | STATIC int strequal(const char *, const char *); |
| 136 | STATIC struct var *find_var(const char *, struct var ***, int *); |
| 137 | |
| 138 | /* |
| 139 | * Initialize the varable symbol tables and import the environment |
| 140 | */ |
| 141 | |
| 142 | #ifdef mkinit |
| 143 | INCLUDE "var.h" |
| 144 | MKINIT char **environ; |
| 145 | INIT { |
| 146 | char **envp; |
| 147 | |
| 148 | initvar(); |
| 149 | for (envp = environ ; *envp ; envp++) { |
| 150 | if (strchr(*envp, '=')) { |
| 151 | setvareq(*envp, VEXPORT|VTEXTFIXED); |
| 152 | } |
| 153 | } |
| 154 | } |
| 155 | #endif |
| 156 | |
| 157 | |
| 158 | /* |
| 159 | * This routine initializes the builtin variables. It is called when the |
| 160 | * shell is initialized and again when a shell procedure is spawned. |
| 161 | */ |
| 162 | |
| 163 | void |
| 164 | initvar(void) |
| 165 | { |
| 166 | const struct varinit *ip; |
| 167 | struct var *vp; |
| 168 | struct var **vpp; |
| 169 | |
| 170 | for (ip = varinit ; (vp = ip->var) != NULL ; ip++) { |
| 171 | if (find_var(ip->text, &vpp, &vp->name_len) != NULL) |
| 172 | continue; |
| 173 | vp->next = *vpp; |
| 174 | *vpp = vp; |
| 175 | vp->text = strdup(ip->text); |
| 176 | vp->flags = ip->flags; |
| 177 | vp->func = ip->func; |
| 178 | } |
| 179 | /* |
| 180 | * PS1 depends on uid |
| 181 | */ |
| 182 | if (find_var("PS1", &vpp, &vps1.name_len) == NULL) { |
| 183 | vps1.next = *vpp; |
| 184 | *vpp = &vps1; |
| 185 | vps1.text = strdup(geteuid() ? "PS1=$ " : "PS1=# "); |
| 186 | vps1.flags = VSTRFIXED|VTEXTFIXED; |
| 187 | } |
| 188 | } |
| 189 | |
| 190 | /* |
| 191 | * Safe version of setvar, returns 1 on success 0 on failure. |
| 192 | */ |
| 193 | |
| 194 | int |
| 195 | setvarsafe(const char *name, const char *val, int flags) |
| 196 | { |
| 197 | struct jmploc jmploc; |
| 198 | struct jmploc *volatile savehandler = handler; |
| 199 | int err = 0; |
| 200 | #ifdef __GNUC__ |
| 201 | (void) &err; |
| 202 | #endif |
| 203 | |
| 204 | if (setjmp(jmploc.loc)) |
| 205 | err = 1; |
| 206 | else { |
| 207 | handler = &jmploc; |
| 208 | setvar(name, val, flags); |
| 209 | } |
| 210 | handler = savehandler; |
| 211 | return err; |
| 212 | } |
| 213 | |
| 214 | /* |
| 215 | * Set the value of a variable. The flags argument is ored with the |
| 216 | * flags of the variable. If val is NULL, the variable is unset. |
| 217 | */ |
| 218 | |
| 219 | void |
| 220 | setvar(const char *name, const char *val, int flags) |
| 221 | { |
| 222 | const char *p; |
| 223 | const char *q; |
| 224 | char *d; |
| 225 | int len; |
| 226 | int namelen; |
| 227 | char *nameeq; |
| 228 | int isbad; |
| 229 | |
| 230 | isbad = 0; |
| 231 | p = name; |
| 232 | if (! is_name(*p)) |
| 233 | isbad = 1; |
| 234 | p++; |
| 235 | for (;;) { |
| 236 | if (! is_in_name(*p)) { |
| 237 | if (*p == '\0' || *p == '=') |
| 238 | break; |
| 239 | isbad = 1; |
| 240 | } |
| 241 | p++; |
| 242 | } |
| 243 | namelen = p - name; |
| 244 | if (isbad) |
| 245 | error("%.*s: bad variable name", namelen, name); |
| 246 | len = namelen + 2; /* 2 is space for '=' and '\0' */ |
| 247 | if (val == NULL) { |
| 248 | flags |= VUNSET; |
| 249 | } else { |
| 250 | len += strlen(val); |
| 251 | } |
| 252 | d = nameeq = ckmalloc(len); |
| 253 | q = name; |
| 254 | while (--namelen >= 0) |
| 255 | *d++ = *q++; |
| 256 | *d++ = '='; |
| 257 | *d = '\0'; |
| 258 | if (val) |
| 259 | scopy(val, d); |
| 260 | setvareq(nameeq, flags); |
| 261 | } |
| 262 | |
| 263 | |
| 264 | |
| 265 | /* |
| 266 | * Same as setvar except that the variable and value are passed in |
| 267 | * the first argument as name=value. Since the first argument will |
| 268 | * be actually stored in the table, it should not be a string that |
| 269 | * will go away. |
| 270 | */ |
| 271 | |
| 272 | void |
| 273 | setvareq(char *s, int flags) |
| 274 | { |
| 275 | struct var *vp, **vpp; |
| 276 | int nlen; |
| 277 | |
| 278 | if (aflag) |
| 279 | flags |= VEXPORT; |
| 280 | vp = find_var(s, &vpp, &nlen); |
| 281 | if (vp != NULL) { |
| 282 | if (vp->flags & VREADONLY) |
| 283 | error("%.*s: is read only", vp->name_len, s); |
| 284 | if (flags & VNOSET) |
| 285 | return; |
| 286 | INTOFF; |
| 287 | |
| 288 | if (vp->func && (flags & VNOFUNC) == 0) |
| 289 | (*vp->func)(s + vp->name_len + 1); |
| 290 | |
| 291 | if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0) |
| 292 | ckfree(vp->text); |
| 293 | |
| 294 | vp->flags &= ~(VTEXTFIXED|VSTACK|VUNSET); |
| 295 | vp->flags |= flags & ~VNOFUNC; |
| 296 | vp->text = s; |
| 297 | |
| 298 | INTON; |
| 299 | return; |
| 300 | } |
| 301 | /* not found */ |
| 302 | if (flags & VNOSET) |
| 303 | return; |
| 304 | vp = ckmalloc(sizeof (*vp)); |
| 305 | vp->flags = flags & ~VNOFUNC; |
| 306 | vp->text = s; |
| 307 | vp->name_len = nlen; |
| 308 | vp->next = *vpp; |
| 309 | vp->func = NULL; |
| 310 | *vpp = vp; |
| 311 | } |
| 312 | |
| 313 | |
| 314 | |
| 315 | /* |
| 316 | * Process a linked list of variable assignments. |
| 317 | */ |
| 318 | |
| 319 | void |
| 320 | listsetvar(struct strlist *list, int flags) |
| 321 | { |
| 322 | struct strlist *lp; |
| 323 | |
| 324 | INTOFF; |
| 325 | for (lp = list ; lp ; lp = lp->next) { |
| 326 | setvareq(savestr(lp->text), flags); |
| 327 | } |
| 328 | INTON; |
| 329 | } |
| 330 | |
| 331 | void |
| 332 | listmklocal(struct strlist *list, int flags) |
| 333 | { |
| 334 | struct strlist *lp; |
| 335 | |
| 336 | for (lp = list ; lp ; lp = lp->next) |
| 337 | mklocal(lp->text, flags); |
| 338 | } |
| 339 | |
| 340 | |
| 341 | /* |
| 342 | * Find the value of a variable. Returns NULL if not set. |
| 343 | */ |
| 344 | |
| 345 | char * |
| 346 | lookupvar(const char *name) |
| 347 | { |
| 348 | struct var *v; |
| 349 | |
| 350 | v = find_var(name, NULL, NULL); |
| 351 | if (v == NULL || v->flags & VUNSET) |
| 352 | return NULL; |
| 353 | return v->text + v->name_len + 1; |
| 354 | } |
| 355 | |
| 356 | |
| 357 | |
| 358 | /* |
| 359 | * Search the environment of a builtin command. If the second argument |
| 360 | * is nonzero, return the value of a variable even if it hasn't been |
| 361 | * exported. |
| 362 | */ |
| 363 | |
| 364 | char * |
| 365 | bltinlookup(const char *name, int doall) |
| 366 | { |
| 367 | struct strlist *sp; |
| 368 | struct var *v; |
| 369 | |
| 370 | for (sp = cmdenviron ; sp ; sp = sp->next) { |
| 371 | if (strequal(sp->text, name)) |
| 372 | return strchr(sp->text, '=') + 1; |
| 373 | } |
| 374 | |
| 375 | v = find_var(name, NULL, NULL); |
| 376 | |
| 377 | if (v == NULL || v->flags & VUNSET || (!doall && !(v->flags & VEXPORT))) |
| 378 | return NULL; |
| 379 | return v->text + v->name_len + 1; |
| 380 | } |
| 381 | |
| 382 | |
| 383 | |
| 384 | /* |
| 385 | * Generate a list of exported variables. This routine is used to construct |
| 386 | * the third argument to execve when executing a program. |
| 387 | */ |
| 388 | |
| 389 | char ** |
| 390 | environment(void) |
| 391 | { |
| 392 | int nenv; |
| 393 | struct var **vpp; |
| 394 | struct var *vp; |
| 395 | char **env; |
| 396 | char **ep; |
| 397 | |
| 398 | nenv = 0; |
| 399 | for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { |
| 400 | for (vp = *vpp ; vp ; vp = vp->next) |
| 401 | if (vp->flags & VEXPORT) |
| 402 | nenv++; |
| 403 | } |
| 404 | ep = env = stalloc((nenv + 1) * sizeof *env); |
| 405 | for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { |
| 406 | for (vp = *vpp ; vp ; vp = vp->next) |
| 407 | if (vp->flags & VEXPORT) |
| 408 | *ep++ = vp->text; |
| 409 | } |
| 410 | *ep = NULL; |
| 411 | return env; |
| 412 | } |
| 413 | |
| 414 | |
| 415 | /* |
| 416 | * Called when a shell procedure is invoked to clear out nonexported |
| 417 | * variables. It is also necessary to reallocate variables of with |
| 418 | * VSTACK set since these are currently allocated on the stack. |
| 419 | */ |
| 420 | |
| 421 | #ifdef mkinit |
| 422 | void shprocvar(void); |
| 423 | |
| 424 | SHELLPROC { |
| 425 | shprocvar(); |
| 426 | } |
| 427 | #endif |
| 428 | |
| 429 | void |
| 430 | shprocvar(void) |
| 431 | { |
| 432 | struct var **vpp; |
| 433 | struct var *vp, **prev; |
| 434 | |
| 435 | for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { |
| 436 | for (prev = vpp ; (vp = *prev) != NULL ; ) { |
| 437 | if ((vp->flags & VEXPORT) == 0) { |
| 438 | *prev = vp->next; |
| 439 | if ((vp->flags & VTEXTFIXED) == 0) |
| 440 | ckfree(vp->text); |
| 441 | if ((vp->flags & VSTRFIXED) == 0) |
| 442 | ckfree(vp); |
| 443 | } else { |
| 444 | if (vp->flags & VSTACK) { |
| 445 | vp->text = savestr(vp->text); |
| 446 | vp->flags &=~ VSTACK; |
| 447 | } |
| 448 | prev = &vp->next; |
| 449 | } |
| 450 | } |
| 451 | } |
| 452 | initvar(); |
| 453 | } |
| 454 | |
| 455 | |
| 456 | |
| 457 | /* |
| 458 | * Command to list all variables which are set. Currently this command |
| 459 | * is invoked from the set command when the set command is called without |
| 460 | * any variables. |
| 461 | */ |
| 462 | |
| 463 | void |
| 464 | print_quoted(const char *p) |
| 465 | { |
| 466 | const char *q; |
| 467 | |
| 468 | if (strcspn(p, "|&;<>()$`\\\"' \t\n*?[]#~=%") == strlen(p)) { |
| 469 | out1fmt("%s", p); |
| 470 | return; |
| 471 | } |
| 472 | while (*p) { |
| 473 | if (*p == '\'') { |
| 474 | out1fmt("\\'"); |
| 475 | p++; |
| 476 | continue; |
| 477 | } |
| 478 | q = index(p, '\''); |
| 479 | if (!q) { |
| 480 | out1fmt("'%s'", p ); |
| 481 | return; |
| 482 | } |
| 483 | out1fmt("'%.*s'", (int)(q - p), p ); |
| 484 | p = q; |
| 485 | } |
| 486 | } |
| 487 | |
| 488 | static int |
| 489 | sort_var(const void *v_v1, const void *v_v2) |
| 490 | { |
| 491 | const struct var * const *v1 = v_v1; |
| 492 | const struct var * const *v2 = v_v2; |
| 493 | |
| 494 | /* XXX Will anyone notice we include the '=' of the shorter name? */ |
| 495 | return strcmp((*v1)->text, (*v2)->text); |
| 496 | } |
| 497 | |
| 498 | /* |
| 499 | * POSIX requires that 'set' (but not export or readonly) output the |
| 500 | * variables in lexicographic order - by the locale's collating order (sigh). |
| 501 | * Maybe we could keep them in an ordered balanced binary tree |
| 502 | * instead of hashed lists. |
| 503 | * For now just roll 'em through qsort for printing... |
| 504 | */ |
| 505 | |
| 506 | int |
| 507 | showvars(const char *name, int flag, int show_value) |
| 508 | { |
| 509 | struct var **vpp; |
| 510 | struct var *vp; |
| 511 | const char *p; |
| 512 | |
| 513 | static struct var **list; /* static in case we are interrupted */ |
| 514 | static int list_len; |
| 515 | int count = 0; |
| 516 | |
| 517 | if (!list) { |
| 518 | list_len = 32; |
| 519 | list = ckmalloc(list_len * sizeof *list); |
| 520 | } |
| 521 | |
| 522 | for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { |
| 523 | for (vp = *vpp ; vp ; vp = vp->next) { |
| 524 | if (flag && !(vp->flags & flag)) |
| 525 | continue; |
| 526 | if (vp->flags & VUNSET && !(show_value & 2)) |
| 527 | continue; |
| 528 | if (count >= list_len) { |
| 529 | list = ckrealloc(list, |
| 530 | (list_len << 1) * sizeof *list); |
| 531 | list_len <<= 1; |
| 532 | } |
| 533 | list[count++] = vp; |
| 534 | } |
| 535 | } |
| 536 | |
| 537 | qsort(list, count, sizeof *list, sort_var); |
| 538 | |
| 539 | for (vpp = list; count--; vpp++) { |
| 540 | vp = *vpp; |
| 541 | if (name) |
| 542 | out1fmt("%s ", name); |
| 543 | for (p = vp->text ; *p != '=' ; p++) |
| 544 | out1c(*p); |
| 545 | if (!(vp->flags & VUNSET) && show_value) { |
| 546 | out1fmt("="); |
| 547 | print_quoted(++p); |
| 548 | } |
| 549 | out1c('\n'); |
| 550 | } |
| 551 | return 0; |
| 552 | } |
| 553 | |
| 554 | |
| 555 | |
| 556 | /* |
| 557 | * The export and readonly commands. |
| 558 | */ |
| 559 | |
| 560 | int |
| 561 | exportcmd(int argc, char **argv) |
| 562 | { |
| 563 | struct var *vp; |
| 564 | char *name; |
| 565 | const char *p; |
| 566 | int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT; |
| 567 | int pflag; |
| 568 | |
| 569 | pflag = nextopt("p") == 'p' ? 3 : 0; |
| 570 | if (argc <= 1 || pflag) { |
| 571 | showvars( pflag ? argv[0] : 0, flag, pflag ); |
| 572 | return 0; |
| 573 | } |
| 574 | |
| 575 | while ((name = *argptr++) != NULL) { |
| 576 | if ((p = strchr(name, '=')) != NULL) { |
| 577 | p++; |
| 578 | } else { |
| 579 | vp = find_var(name, NULL, NULL); |
| 580 | if (vp != NULL) { |
| 581 | vp->flags |= flag; |
| 582 | continue; |
| 583 | } |
| 584 | } |
| 585 | setvar(name, p, flag); |
| 586 | } |
| 587 | return 0; |
| 588 | } |
| 589 | |
| 590 | |
| 591 | /* |
| 592 | * The "local" command. |
| 593 | */ |
| 594 | |
| 595 | int |
| 596 | localcmd(int argc, char **argv) |
| 597 | { |
| 598 | char *name; |
| 599 | |
| 600 | if (! in_function()) |
| 601 | error("Not in a function"); |
| 602 | while ((name = *argptr++) != NULL) { |
| 603 | mklocal(name, 0); |
| 604 | } |
| 605 | return 0; |
| 606 | } |
| 607 | |
| 608 | |
| 609 | /* |
| 610 | * Make a variable a local variable. When a variable is made local, it's |
| 611 | * value and flags are saved in a localvar structure. The saved values |
| 612 | * will be restored when the shell function returns. We handle the name |
| 613 | * "-" as a special case. |
| 614 | */ |
| 615 | |
| 616 | void |
| 617 | mklocal(const char *name, int flags) |
| 618 | { |
| 619 | struct localvar *lvp; |
| 620 | struct var **vpp; |
| 621 | struct var *vp; |
| 622 | |
| 623 | INTOFF; |
| 624 | lvp = ckmalloc(sizeof (struct localvar)); |
| 625 | if (name[0] == '-' && name[1] == '\0') { |
| 626 | char *p; |
| 627 | p = ckmalloc(sizeof_optlist); |
| 628 | lvp->text = memcpy(p, optlist, sizeof_optlist); |
| 629 | vp = NULL; |
| 630 | } else { |
| 631 | vp = find_var(name, &vpp, NULL); |
| 632 | if (vp == NULL) { |
| 633 | if (strchr(name, '=')) |
| 634 | setvareq(savestr(name), VSTRFIXED|flags); |
| 635 | else |
| 636 | setvar(name, NULL, VSTRFIXED|flags); |
| 637 | vp = *vpp; /* the new variable */ |
| 638 | lvp->text = NULL; |
| 639 | lvp->flags = VUNSET; |
| 640 | } else { |
| 641 | lvp->text = vp->text; |
| 642 | lvp->flags = vp->flags; |
| 643 | vp->flags |= VSTRFIXED|VTEXTFIXED; |
| 644 | if (name[vp->name_len] == '=') |
| 645 | setvareq(savestr(name), flags); |
| 646 | } |
| 647 | } |
| 648 | lvp->vp = vp; |
| 649 | lvp->next = localvars; |
| 650 | localvars = lvp; |
| 651 | INTON; |
| 652 | } |
| 653 | |
| 654 | |
| 655 | /* |
| 656 | * Called after a function returns. |
| 657 | */ |
| 658 | |
| 659 | void |
| 660 | poplocalvars(void) |
| 661 | { |
| 662 | struct localvar *lvp; |
| 663 | struct var *vp; |
| 664 | |
| 665 | while ((lvp = localvars) != NULL) { |
| 666 | localvars = lvp->next; |
| 667 | vp = lvp->vp; |
| 668 | TRACE(("poplocalvar %s", vp ? vp->text : "-")); |
| 669 | if (vp == NULL) { /* $- saved */ |
| 670 | memcpy(optlist, lvp->text, sizeof_optlist); |
| 671 | ckfree(lvp->text); |
| 672 | } else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) { |
| 673 | (void)unsetvar(vp->text, 0); |
| 674 | } else { |
| 675 | if (vp->func && (vp->flags & VNOFUNC) == 0) |
| 676 | (*vp->func)(lvp->text + vp->name_len + 1); |
| 677 | if ((vp->flags & VTEXTFIXED) == 0) |
| 678 | ckfree(vp->text); |
| 679 | vp->flags = lvp->flags; |
| 680 | vp->text = lvp->text; |
| 681 | } |
| 682 | ckfree(lvp); |
| 683 | } |
| 684 | } |
| 685 | |
| 686 | |
| 687 | int |
| 688 | setvarcmd(int argc, char **argv) |
| 689 | { |
| 690 | if (argc <= 2) |
| 691 | return unsetcmd(argc, argv); |
| 692 | else if (argc == 3) |
| 693 | setvar(argv[1], argv[2], 0); |
| 694 | else |
| 695 | error("List assignment not implemented"); |
| 696 | return 0; |
| 697 | } |
| 698 | |
| 699 | |
| 700 | /* |
| 701 | * The unset builtin command. We unset the function before we unset the |
| 702 | * variable to allow a function to be unset when there is a readonly variable |
| 703 | * with the same name. |
| 704 | */ |
| 705 | |
| 706 | int |
| 707 | unsetcmd(int argc, char **argv) |
| 708 | { |
| 709 | char **ap; |
| 710 | int i; |
| 711 | int flg_func = 0; |
| 712 | int flg_var = 0; |
| 713 | int ret = 0; |
| 714 | |
| 715 | while ((i = nextopt("evf")) != '\0') { |
| 716 | if (i == 'f') |
| 717 | flg_func = 1; |
| 718 | else |
| 719 | flg_var = i; |
| 720 | } |
| 721 | if (flg_func == 0 && flg_var == 0) |
| 722 | flg_var = 1; |
| 723 | |
| 724 | for (ap = argptr; *ap ; ap++) { |
| 725 | if (flg_func) |
| 726 | ret |= unsetfunc(*ap); |
| 727 | if (flg_var) |
| 728 | ret |= unsetvar(*ap, flg_var == 'e'); |
| 729 | } |
| 730 | return ret; |
| 731 | } |
| 732 | |
| 733 | |
| 734 | /* |
| 735 | * Unset the specified variable. |
| 736 | */ |
| 737 | |
| 738 | int |
| 739 | unsetvar(const char *s, int unexport) |
| 740 | { |
| 741 | struct var **vpp; |
| 742 | struct var *vp; |
| 743 | |
| 744 | vp = find_var(s, &vpp, NULL); |
| 745 | if (vp == NULL) |
| 746 | return 1; |
| 747 | |
| 748 | if (vp->flags & VREADONLY) |
| 749 | return (1); |
| 750 | |
| 751 | INTOFF; |
| 752 | if (unexport) { |
| 753 | vp->flags &= ~VEXPORT; |
| 754 | } else { |
| 755 | if (vp->text[vp->name_len + 1] != '\0') |
| 756 | setvar(s, nullstr, 0); |
| 757 | vp->flags &= ~VEXPORT; |
| 758 | vp->flags |= VUNSET; |
| 759 | if ((vp->flags & VSTRFIXED) == 0) { |
| 760 | if ((vp->flags & VTEXTFIXED) == 0) |
| 761 | ckfree(vp->text); |
| 762 | *vpp = vp->next; |
| 763 | ckfree(vp); |
| 764 | } |
| 765 | } |
| 766 | INTON; |
| 767 | return 0; |
| 768 | } |
| 769 | |
| 770 | |
| 771 | /* |
| 772 | * Returns true if the two strings specify the same varable. The first |
| 773 | * variable name is terminated by '='; the second may be terminated by |
| 774 | * either '=' or '\0'. |
| 775 | */ |
| 776 | |
| 777 | STATIC int |
| 778 | strequal(const char *p, const char *q) |
| 779 | { |
| 780 | while (*p == *q++) { |
| 781 | if (*p++ == '=') |
| 782 | return 1; |
| 783 | } |
| 784 | if (*p == '=' && *(q - 1) == '\0') |
| 785 | return 1; |
| 786 | return 0; |
| 787 | } |
| 788 | |
| 789 | /* |
| 790 | * Search for a variable. |
| 791 | * 'name' may be terminated by '=' or a NUL. |
| 792 | * vppp is set to the pointer to vp, or the list head if vp isn't found |
| 793 | * lenp is set to the number of charactets in 'name' |
| 794 | */ |
| 795 | |
| 796 | STATIC struct var * |
| 797 | find_var(const char *name, struct var ***vppp, int *lenp) |
| 798 | { |
| 799 | unsigned int hashval; |
| 800 | int len; |
| 801 | struct var *vp, **vpp; |
| 802 | const char *p = name; |
| 803 | |
| 804 | hashval = 0; |
| 805 | while (*p && *p != '=') |
| 806 | hashval = 2 * hashval + (unsigned char)*p++; |
| 807 | len = p - name; |
| 808 | |
| 809 | if (lenp) |
| 810 | *lenp = len; |
| 811 | vpp = &vartab[hashval % VTABSIZE]; |
| 812 | if (vppp) |
| 813 | *vppp = vpp; |
| 814 | |
| 815 | for (vp = *vpp ; vp ; vpp = &vp->next, vp = *vpp) { |
| 816 | if (vp->name_len != len) |
| 817 | continue; |
| 818 | if (memcmp(vp->text, name, len) != 0) |
| 819 | continue; |
| 820 | if (vppp) |
| 821 | *vppp = vpp; |
| 822 | return vp; |
| 823 | } |
| 824 | return NULL; |
| 825 | } |