var.c revision 259846
1184610Salfred/*- 2184610Salfred * Copyright (c) 1991, 1993 3189002Sed * The Regents of the University of California. All rights reserved. 4184610Salfred * 5184610Salfred * This code is derived from software contributed to Berkeley by 6184610Salfred * Kenneth Almquist. 7184610Salfred * 8184610Salfred * Redistribution and use in source and binary forms, with or without 9184610Salfred * modification, are permitted provided that the following conditions 10184610Salfred * are met: 11184610Salfred * 1. Redistributions of source code must retain the above copyright 12184610Salfred * notice, this list of conditions and the following disclaimer. 13184610Salfred * 2. Redistributions in binary form must reproduce the above copyright 14184610Salfred * notice, this list of conditions and the following disclaimer in the 15184610Salfred * documentation and/or other materials provided with the distribution. 16184610Salfred * 4. Neither the name of the University nor the names of its contributors 17184610Salfred * may be used to endorse or promote products derived from this software 18184610Salfred * without specific prior written permission. 19184610Salfred * 20184610Salfred * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21184610Salfred * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22184610Salfred * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23184610Salfred * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24184610Salfred * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25184610Salfred * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26184610Salfred * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27184610Salfred * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28184610Salfred * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29184610Salfred * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30184610Salfred * SUCH DAMAGE. 31187170Sthompsa */ 32187170Sthompsa 33184610Salfred#ifndef lint 34184610Salfred#if 0 35184610Salfredstatic char sccsid[] = "@(#)var.c 8.3 (Berkeley) 5/4/95"; 36184610Salfred#endif 37184610Salfred#endif /* not lint */ 38184610Salfred#include <sys/cdefs.h> 39184610Salfred__FBSDID("$FreeBSD: head/bin/sh/var.c 259846 2013-12-24 22:38:24Z jilles $"); 40184610Salfred 41184610Salfred#include <unistd.h> 42184610Salfred#include <stdlib.h> 43184610Salfred#include <paths.h> 44184610Salfred 45184610Salfred/* 46184610Salfred * Shell variables. 47184610Salfred */ 48184610Salfred 49184610Salfred#include <locale.h> 50184610Salfred#include <langinfo.h> 51184610Salfred 52184610Salfred#include "shell.h" 53184610Salfred#include "output.h" 54184610Salfred#include "expand.h" 55184610Salfred#include "nodes.h" /* for other headers */ 56184610Salfred#include "eval.h" /* defines cmdenviron */ 57184610Salfred#include "exec.h" 58184610Salfred#include "syntax.h" 59184610Salfred#include "options.h" 60184610Salfred#include "mail.h" 61184610Salfred#include "var.h" 62184610Salfred#include "memalloc.h" 63184610Salfred#include "error.h" 64184610Salfred#include "mystring.h" 65184610Salfred#include "parser.h" 66184610Salfred#include "builtins.h" 67184610Salfred#ifndef NO_HISTORY 68184610Salfred#include "myhistedit.h" 69184610Salfred#endif 70184610Salfred 71184610Salfred 72184610Salfred#define VTABSIZE 39 73184610Salfred 74184610Salfred 75184610Salfredstruct varinit { 76184610Salfred struct var *var; 77184610Salfred int flags; 78184610Salfred const char *text; 79184610Salfred void (*func)(const char *); 80184610Salfred}; 81184610Salfred 82184610Salfred 83184610Salfred#ifndef NO_HISTORY 84184610Salfredstruct var vhistsize; 85184610Salfredstruct var vterm; 86184610Salfred#endif 87184610Salfredstruct var vifs; 88184610Salfredstruct var vmail; 89184610Salfredstruct var vmpath; 90184610Salfredstruct var vpath; 91184610Salfredstruct var vppid; 92184610Salfredstruct var vps1; 93184610Salfredstruct var vps2; 94184610Salfredstruct var vps4; 95184610Salfredstatic struct var voptind; 96184610Salfredstruct var vdisvfork; 97184610Salfred 98184610Salfredint forcelocal; 99184610Salfred 100184610Salfredstatic const struct varinit varinit[] = { 101184610Salfred#ifndef NO_HISTORY 102184610Salfred { &vhistsize, VUNSET, "HISTSIZE=", 103184610Salfred sethistsize }, 104184610Salfred#endif 105184610Salfred { &vifs, 0, "IFS= \t\n", 106184610Salfred NULL }, 107184610Salfred { &vmail, VUNSET, "MAIL=", 108184610Salfred NULL }, 109184610Salfred { &vmpath, VUNSET, "MAILPATH=", 110184610Salfred NULL }, 111184610Salfred { &vpath, 0, "PATH=" _PATH_DEFPATH, 112184610Salfred changepath }, 113184610Salfred { &vppid, VUNSET, "PPID=", 114184610Salfred NULL }, 115184610Salfred /* 116184610Salfred * vps1 depends on uid 117184610Salfred */ 118184610Salfred { &vps2, 0, "PS2=> ", 119184610Salfred NULL }, 120184610Salfred { &vps4, 0, "PS4=+ ", 121184610Salfred NULL }, 122184610Salfred#ifndef NO_HISTORY 123184610Salfred { &vterm, VUNSET, "TERM=", 124184610Salfred setterm }, 125184610Salfred#endif 126184610Salfred { &voptind, 0, "OPTIND=1", 127184610Salfred getoptsreset }, 128184610Salfred { &vdisvfork, VUNSET, "SH_DISABLE_VFORK=", 129184610Salfred NULL }, 130184610Salfred { NULL, 0, NULL, 131184610Salfred NULL } 132184610Salfred}; 133184610Salfred 134184610Salfredstatic struct var *vartab[VTABSIZE]; 135184610Salfred 136184610Salfredstatic const char *const locale_names[7] = { 137184610Salfred "LC_COLLATE", "LC_CTYPE", "LC_MONETARY", 138184610Salfred "LC_NUMERIC", "LC_TIME", "LC_MESSAGES", NULL 139184610Salfred}; 140184610Salfredstatic const int locale_categories[7] = { 141184610Salfred LC_COLLATE, LC_CTYPE, LC_MONETARY, LC_NUMERIC, LC_TIME, LC_MESSAGES, 0 142184610Salfred}; 143184610Salfred 144184610Salfredstatic int varequal(const char *, const char *); 145184610Salfredstatic struct var *find_var(const char *, struct var ***, int *); 146184610Salfredstatic int localevar(const char *); 147184610Salfred 148184610Salfredextern char **environ; 149184610Salfred 150184610Salfred/* 151184610Salfred * This routine initializes the builtin variables and imports the environment. 152184610Salfred * It is called when the shell is initialized. 153184610Salfred */ 154184610Salfred 155184610Salfredvoid 156184610Salfredinitvar(void) 157184610Salfred{ 158184610Salfred char ppid[20]; 159184610Salfred const struct varinit *ip; 160184610Salfred struct var *vp; 161184610Salfred struct var **vpp; 162184610Salfred char **envp; 163184610Salfred 164184610Salfred for (ip = varinit ; (vp = ip->var) != NULL ; ip++) { 165184610Salfred if (find_var(ip->text, &vpp, &vp->name_len) != NULL) 166184610Salfred continue; 167184610Salfred vp->next = *vpp; 168184610Salfred *vpp = vp; 169184610Salfred vp->text = __DECONST(char *, ip->text); 170184610Salfred vp->flags = ip->flags | VSTRFIXED | VTEXTFIXED; 171184610Salfred vp->func = ip->func; 172184610Salfred } 173184610Salfred /* 174184610Salfred * PS1 depends on uid 175184610Salfred */ 176184610Salfred if (find_var("PS1", &vpp, &vps1.name_len) == NULL) { 177184610Salfred vps1.next = *vpp; 178184610Salfred *vpp = &vps1; 179184610Salfred vps1.text = __DECONST(char *, geteuid() ? "PS1=$ " : "PS1=# "); 180184610Salfred vps1.flags = VSTRFIXED|VTEXTFIXED; 181184610Salfred } 182184610Salfred if ((vppid.flags & VEXPORT) == 0) { 183184610Salfred fmtstr(ppid, sizeof(ppid), "%d", (int)getppid()); 184184610Salfred setvarsafe("PPID", ppid, 0); 185184610Salfred } 186184610Salfred for (envp = environ ; *envp ; envp++) { 187184610Salfred if (strchr(*envp, '=')) { 188184610Salfred setvareq(*envp, VEXPORT|VTEXTFIXED); 189184610Salfred } 190184610Salfred } 191184610Salfred setvareq("OPTIND=1", VTEXTFIXED); 192184610Salfred} 193184610Salfred 194184610Salfred/* 195184610Salfred * Safe version of setvar, returns 1 on success 0 on failure. 196184610Salfred */ 197184610Salfred 198184610Salfredint 199184610Salfredsetvarsafe(const char *name, const char *val, int flags) 200184610Salfred{ 201184610Salfred struct jmploc jmploc; 202184610Salfred struct jmploc *const savehandler = handler; 203184610Salfred int err = 0; 204184610Salfred int inton; 205184610Salfred 206184610Salfred inton = is_int_on(); 207184610Salfred if (setjmp(jmploc.loc)) 208184610Salfred err = 1; 209184610Salfred else { 210184610Salfred handler = &jmploc; 211184610Salfred setvar(name, val, flags); 212184610Salfred } 213184610Salfred handler = savehandler; 214184610Salfred SETINTON(inton); 215184610Salfred return err; 216184610Salfred} 217184610Salfred 218184610Salfred/* 219184610Salfred * Set the value of a variable. The flags argument is stored with the 220184610Salfred * flags of the variable. If val is NULL, the variable is unset. 221184610Salfred */ 222184610Salfred 223184610Salfredvoid 224184610Salfredsetvar(const char *name, const char *val, int flags) 225184610Salfred{ 226184610Salfred const char *p; 227184610Salfred size_t len; 228184610Salfred size_t namelen; 229184610Salfred size_t vallen; 230184610Salfred char *nameeq; 231184610Salfred int isbad; 232184610Salfred 233184610Salfred isbad = 0; 234184610Salfred p = name; 235184610Salfred if (! is_name(*p)) 236184610Salfred isbad = 1; 237184610Salfred p++; 238184610Salfred for (;;) { 239184610Salfred if (! is_in_name(*p)) { 240184610Salfred if (*p == '\0' || *p == '=') 241184610Salfred break; 242184610Salfred isbad = 1; 243184610Salfred } 244184610Salfred p++; 245184610Salfred } 246184610Salfred namelen = p - name; 247184610Salfred if (isbad) 248184610Salfred error("%.*s: bad variable name", (int)namelen, name); 249184610Salfred len = namelen + 2; /* 2 is space for '=' and '\0' */ 250184610Salfred if (val == NULL) { 251184610Salfred flags |= VUNSET; 252184610Salfred vallen = 0; 253184610Salfred } else { 254184610Salfred vallen = strlen(val); 255184610Salfred len += vallen; 256184610Salfred } 257184610Salfred nameeq = ckmalloc(len); 258269564Shselasky memcpy(nameeq, name, namelen); 259269564Shselasky nameeq[namelen] = '='; 260269564Shselasky if (val) 261269564Shselasky memcpy(nameeq + namelen + 1, val, vallen + 1); 262184610Salfred else 263269564Shselasky nameeq[namelen + 1] = '\0'; 264184610Salfred setvareq(nameeq, flags); 265184610Salfred} 266269564Shselasky 267184610Salfredstatic int 268184610Salfredlocalevar(const char *s) 269269564Shselasky{ 270184610Salfred const char *const *ss; 271269564Shselasky 272184610Salfred if (*s != 'L') 273184610Salfred return 0; 274184610Salfred if (varequal(s + 1, "ANG")) 275184610Salfred return 1; 276192984Sthompsa if (strncmp(s + 1, "C_", 2) != 0) 277184610Salfred return 0; 278184610Salfred if (varequal(s + 3, "ALL")) 279184610Salfred return 1; 280184610Salfred for (ss = locale_names; *ss ; ss++) 281184610Salfred if (varequal(s + 3, *ss + 3)) 282184610Salfred return 1; 283184610Salfred return 0; 284184610Salfred} 285184610Salfred 286192552Sthompsa 287184610Salfred/* 288184610Salfred * Sets/unsets an environment variable from a pointer that may actually be a 289184610Salfred * pointer into environ where the string should not be manipulated. 290184610Salfred */ 291192984Sthompsastatic void 292184610Salfredchange_env(const char *s, int set) 293184610Salfred{ 294184610Salfred char *eqp; 295184610Salfred char *ss; 296184610Salfred 297184610Salfred ss = savestr(s); 298184610Salfred if ((eqp = strchr(ss, '=')) != NULL) 299184610Salfred *eqp = '\0'; 300184610Salfred if (set && eqp != NULL) 301184610Salfred (void) setenv(ss, eqp + 1, 1); 302184610Salfred else 303192552Sthompsa (void) unsetenv(ss); 304184610Salfred ckfree(ss); 305184610Salfred 306184610Salfred return; 307192984Sthompsa} 308192984Sthompsa 309192984Sthompsa 310184610Salfred/* 311184610Salfred * Same as setvar except that the variable and value are passed in 312184610Salfred * the first argument as name=value. Since the first argument will 313184610Salfred * be actually stored in the table, it should not be a string that 314192984Sthompsa * will go away. 315184610Salfred */ 316184610Salfred 317184610Salfredvoid 318184610Salfredsetvareq(char *s, int flags) 319184610Salfred{ 320184610Salfred struct var *vp, **vpp; 321184610Salfred int nlen; 322184610Salfred 323184610Salfred if (aflag) 324184610Salfred flags |= VEXPORT; 325184610Salfred if (forcelocal && !(flags & (VNOSET | VNOLOCAL))) 326184610Salfred mklocal(s); 327184610Salfred vp = find_var(s, &vpp, &nlen); 328184610Salfred if (vp != NULL) { 329184610Salfred if (vp->flags & VREADONLY) 330184610Salfred error("%.*s: is read only", vp->name_len, s); 331192984Sthompsa if (flags & VNOSET) 332184610Salfred return; 333184610Salfred INTOFF; 334192984Sthompsa 335184610Salfred if (vp->func && (flags & VNOFUNC) == 0) 336184610Salfred (*vp->func)(s + vp->name_len + 1); 337184610Salfred 338184610Salfred if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0) 339184610Salfred ckfree(vp->text); 340184610Salfred 341184610Salfred vp->flags &= ~(VTEXTFIXED|VSTACK|VUNSET); 342269564Shselasky vp->flags |= flags; 343269564Shselasky vp->text = s; 344184610Salfred 345184610Salfred /* 346184610Salfred * We could roll this to a function, to handle it as 347184610Salfred * a regular variable function callback, but why bother? 348184610Salfred * 349184610Salfred * Note: this assumes iflag is not set to 1 initially. 350184610Salfred * As part of initvar(), this is called before arguments 351184610Salfred * are looked at. 352184610Salfred */ 353184610Salfred if ((vp == &vmpath || (vp == &vmail && ! mpathset())) && 354184610Salfred iflag == 1) 355193045Sthompsa chkmail(1); 356184610Salfred if ((vp->flags & VEXPORT) && localevar(s)) { 357269564Shselasky change_env(s, 1); 358269564Shselasky (void) setlocale(LC_ALL, ""); 359184610Salfred updatecharset(); 360184610Salfred } 361 INTON; 362 return; 363 } 364 /* not found */ 365 if (flags & VNOSET) 366 return; 367 vp = ckmalloc(sizeof (*vp)); 368 vp->flags = flags; 369 vp->text = s; 370 vp->name_len = nlen; 371 vp->next = *vpp; 372 vp->func = NULL; 373 INTOFF; 374 *vpp = vp; 375 if ((vp->flags & VEXPORT) && localevar(s)) { 376 change_env(s, 1); 377 (void) setlocale(LC_ALL, ""); 378 updatecharset(); 379 } 380 INTON; 381} 382 383 384 385/* 386 * Process a linked list of variable assignments. 387 */ 388 389void 390listsetvar(struct strlist *list, int flags) 391{ 392 struct strlist *lp; 393 394 INTOFF; 395 for (lp = list ; lp ; lp = lp->next) { 396 setvareq(savestr(lp->text), flags); 397 } 398 INTON; 399} 400 401 402 403/* 404 * Find the value of a variable. Returns NULL if not set. 405 */ 406 407char * 408lookupvar(const char *name) 409{ 410 struct var *v; 411 412 v = find_var(name, NULL, NULL); 413 if (v == NULL || v->flags & VUNSET) 414 return NULL; 415 return v->text + v->name_len + 1; 416} 417 418 419 420/* 421 * Search the environment of a builtin command. If the second argument 422 * is nonzero, return the value of a variable even if it hasn't been 423 * exported. 424 */ 425 426char * 427bltinlookup(const char *name, int doall) 428{ 429 struct strlist *sp; 430 struct var *v; 431 char *result; 432 433 result = NULL; 434 for (sp = cmdenviron ; sp ; sp = sp->next) { 435 if (varequal(sp->text, name)) 436 result = strchr(sp->text, '=') + 1; 437 } 438 if (result != NULL) 439 return result; 440 441 v = find_var(name, NULL, NULL); 442 if (v == NULL || v->flags & VUNSET || 443 (!doall && (v->flags & VEXPORT) == 0)) 444 return NULL; 445 return v->text + v->name_len + 1; 446} 447 448 449/* 450 * Set up locale for a builtin (LANG/LC_* assignments). 451 */ 452void 453bltinsetlocale(void) 454{ 455 struct strlist *lp; 456 int act = 0; 457 char *loc, *locdef; 458 int i; 459 460 for (lp = cmdenviron ; lp ; lp = lp->next) { 461 if (localevar(lp->text)) { 462 act = 1; 463 break; 464 } 465 } 466 if (!act) 467 return; 468 loc = bltinlookup("LC_ALL", 0); 469 INTOFF; 470 if (loc != NULL) { 471 setlocale(LC_ALL, loc); 472 INTON; 473 updatecharset(); 474 return; 475 } 476 locdef = bltinlookup("LANG", 0); 477 for (i = 0; locale_names[i] != NULL; i++) { 478 loc = bltinlookup(locale_names[i], 0); 479 if (loc == NULL) 480 loc = locdef; 481 if (loc != NULL) 482 setlocale(locale_categories[i], loc); 483 } 484 INTON; 485 updatecharset(); 486} 487 488/* 489 * Undo the effect of bltinlocaleset(). 490 */ 491void 492bltinunsetlocale(void) 493{ 494 struct strlist *lp; 495 496 INTOFF; 497 for (lp = cmdenviron ; lp ; lp = lp->next) { 498 if (localevar(lp->text)) { 499 setlocale(LC_ALL, ""); 500 updatecharset(); 501 return; 502 } 503 } 504 INTON; 505} 506 507/* 508 * Update the localeisutf8 flag. 509 */ 510void 511updatecharset(void) 512{ 513 char *charset; 514 515 charset = nl_langinfo(CODESET); 516 localeisutf8 = !strcmp(charset, "UTF-8"); 517} 518 519void 520initcharset(void) 521{ 522 updatecharset(); 523 initial_localeisutf8 = localeisutf8; 524} 525 526/* 527 * Generate a list of exported variables. This routine is used to construct 528 * the third argument to execve when executing a program. 529 */ 530 531char ** 532environment(void) 533{ 534 int nenv; 535 struct var **vpp; 536 struct var *vp; 537 char **env, **ep; 538 539 nenv = 0; 540 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { 541 for (vp = *vpp ; vp ; vp = vp->next) 542 if (vp->flags & VEXPORT) 543 nenv++; 544 } 545 ep = env = stalloc((nenv + 1) * sizeof *env); 546 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { 547 for (vp = *vpp ; vp ; vp = vp->next) 548 if (vp->flags & VEXPORT) 549 *ep++ = vp->text; 550 } 551 *ep = NULL; 552 return env; 553} 554 555 556static int 557var_compare(const void *a, const void *b) 558{ 559 const char *const *sa, *const *sb; 560 561 sa = a; 562 sb = b; 563 /* 564 * This compares two var=value strings which creates a different 565 * order from what you would probably expect. POSIX is somewhat 566 * ambiguous on what should be sorted exactly. 567 */ 568 return strcoll(*sa, *sb); 569} 570 571 572/* 573 * Command to list all variables which are set. This is invoked from the 574 * set command when it is called without any options or operands. 575 */ 576 577int 578showvarscmd(int argc __unused, char **argv __unused) 579{ 580 struct var **vpp; 581 struct var *vp; 582 const char *s; 583 const char **vars; 584 int i, n; 585 586 /* 587 * POSIX requires us to sort the variables. 588 */ 589 n = 0; 590 for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) { 591 for (vp = *vpp; vp; vp = vp->next) { 592 if (!(vp->flags & VUNSET)) 593 n++; 594 } 595 } 596 597 INTOFF; 598 vars = ckmalloc(n * sizeof(*vars)); 599 i = 0; 600 for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) { 601 for (vp = *vpp; vp; vp = vp->next) { 602 if (!(vp->flags & VUNSET)) 603 vars[i++] = vp->text; 604 } 605 } 606 607 qsort(vars, n, sizeof(*vars), var_compare); 608 for (i = 0; i < n; i++) { 609 /* 610 * Skip improper variable names so the output remains usable as 611 * shell input. 612 */ 613 if (!isassignment(vars[i])) 614 continue; 615 s = strchr(vars[i], '='); 616 s++; 617 outbin(vars[i], s - vars[i], out1); 618 out1qstr(s); 619 out1c('\n'); 620 } 621 ckfree(vars); 622 INTON; 623 624 return 0; 625} 626 627 628 629/* 630 * The export and readonly commands. 631 */ 632 633int 634exportcmd(int argc __unused, char **argv) 635{ 636 struct var **vpp; 637 struct var *vp; 638 char **ap; 639 char *name; 640 char *p; 641 char *cmdname; 642 int ch, values; 643 int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT; 644 645 cmdname = argv[0]; 646 values = 0; 647 while ((ch = nextopt("p")) != '\0') { 648 switch (ch) { 649 case 'p': 650 values = 1; 651 break; 652 } 653 } 654 655 if (values && *argptr != NULL) 656 error("-p requires no arguments"); 657 if (*argptr != NULL) { 658 for (ap = argptr; (name = *ap) != NULL; ap++) { 659 if ((p = strchr(name, '=')) != NULL) { 660 p++; 661 } else { 662 vp = find_var(name, NULL, NULL); 663 if (vp != NULL) { 664 vp->flags |= flag; 665 if ((vp->flags & VEXPORT) && localevar(vp->text)) { 666 change_env(vp->text, 1); 667 (void) setlocale(LC_ALL, ""); 668 updatecharset(); 669 } 670 continue; 671 } 672 } 673 setvar(name, p, flag); 674 } 675 } else { 676 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { 677 for (vp = *vpp ; vp ; vp = vp->next) { 678 if (vp->flags & flag) { 679 if (values) { 680 /* 681 * Skip improper variable names 682 * so the output remains usable 683 * as shell input. 684 */ 685 if (!isassignment(vp->text)) 686 continue; 687 out1str(cmdname); 688 out1c(' '); 689 } 690 if (values && !(vp->flags & VUNSET)) { 691 outbin(vp->text, 692 vp->name_len + 1, out1); 693 out1qstr(vp->text + 694 vp->name_len + 1); 695 } else 696 outbin(vp->text, vp->name_len, 697 out1); 698 out1c('\n'); 699 } 700 } 701 } 702 } 703 return 0; 704} 705 706 707/* 708 * The "local" command. 709 */ 710 711int 712localcmd(int argc __unused, char **argv __unused) 713{ 714 char *name; 715 716 nextopt(""); 717 if (! in_function()) 718 error("Not in a function"); 719 while ((name = *argptr++) != NULL) { 720 mklocal(name); 721 } 722 return 0; 723} 724 725 726/* 727 * Make a variable a local variable. When a variable is made local, it's 728 * value and flags are saved in a localvar structure. The saved values 729 * will be restored when the shell function returns. We handle the name 730 * "-" as a special case. 731 */ 732 733void 734mklocal(char *name) 735{ 736 struct localvar *lvp; 737 struct var **vpp; 738 struct var *vp; 739 740 INTOFF; 741 lvp = ckmalloc(sizeof (struct localvar)); 742 if (name[0] == '-' && name[1] == '\0') { 743 lvp->text = ckmalloc(sizeof optlist); 744 memcpy(lvp->text, optlist, sizeof optlist); 745 vp = NULL; 746 } else { 747 vp = find_var(name, &vpp, NULL); 748 if (vp == NULL) { 749 if (strchr(name, '=')) 750 setvareq(savestr(name), VSTRFIXED | VNOLOCAL); 751 else 752 setvar(name, NULL, VSTRFIXED | VNOLOCAL); 753 vp = *vpp; /* the new variable */ 754 lvp->text = NULL; 755 lvp->flags = VUNSET; 756 } else { 757 lvp->text = vp->text; 758 lvp->flags = vp->flags; 759 vp->flags |= VSTRFIXED|VTEXTFIXED; 760 if (name[vp->name_len] == '=') 761 setvareq(savestr(name), VNOLOCAL); 762 } 763 } 764 lvp->vp = vp; 765 lvp->next = localvars; 766 localvars = lvp; 767 INTON; 768} 769 770 771/* 772 * Called after a function returns. 773 */ 774 775void 776poplocalvars(void) 777{ 778 struct localvar *lvp; 779 struct var *vp; 780 781 while ((lvp = localvars) != NULL) { 782 localvars = lvp->next; 783 vp = lvp->vp; 784 if (vp == NULL) { /* $- saved */ 785 memcpy(optlist, lvp->text, sizeof optlist); 786 ckfree(lvp->text); 787 optschanged(); 788 } else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) { 789 (void)unsetvar(vp->text); 790 } else { 791 if ((vp->flags & VTEXTFIXED) == 0) 792 ckfree(vp->text); 793 vp->flags = lvp->flags; 794 vp->text = lvp->text; 795 } 796 ckfree(lvp); 797 } 798} 799 800 801int 802setvarcmd(int argc, char **argv) 803{ 804 if (argc <= 2) 805 return unsetcmd(argc, argv); 806 else if (argc == 3) 807 setvar(argv[1], argv[2], 0); 808 else 809 error("too many arguments"); 810 return 0; 811} 812 813 814/* 815 * The unset builtin command. 816 */ 817 818int 819unsetcmd(int argc __unused, char **argv __unused) 820{ 821 char **ap; 822 int i; 823 int flg_func = 0; 824 int flg_var = 0; 825 int ret = 0; 826 827 while ((i = nextopt("vf")) != '\0') { 828 if (i == 'f') 829 flg_func = 1; 830 else 831 flg_var = 1; 832 } 833 if (flg_func == 0 && flg_var == 0) 834 flg_var = 1; 835 836 for (ap = argptr; *ap ; ap++) { 837 if (flg_func) 838 ret |= unsetfunc(*ap); 839 if (flg_var) 840 ret |= unsetvar(*ap); 841 } 842 return ret; 843} 844 845 846/* 847 * Unset the specified variable. 848 */ 849 850int 851unsetvar(const char *s) 852{ 853 struct var **vpp; 854 struct var *vp; 855 856 vp = find_var(s, &vpp, NULL); 857 if (vp == NULL) 858 return (0); 859 if (vp->flags & VREADONLY) 860 return (1); 861 INTOFF; 862 if (vp->text[vp->name_len + 1] != '\0') 863 setvar(s, nullstr, 0); 864 if ((vp->flags & VEXPORT) && localevar(vp->text)) { 865 change_env(s, 0); 866 setlocale(LC_ALL, ""); 867 updatecharset(); 868 } 869 vp->flags &= ~VEXPORT; 870 vp->flags |= VUNSET; 871 if ((vp->flags & VSTRFIXED) == 0) { 872 if ((vp->flags & VTEXTFIXED) == 0) 873 ckfree(vp->text); 874 *vpp = vp->next; 875 ckfree(vp); 876 } 877 INTON; 878 return (0); 879} 880 881 882 883/* 884 * Returns true if the two strings specify the same variable. The first 885 * variable name is terminated by '='; the second may be terminated by 886 * either '=' or '\0'. 887 */ 888 889static int 890varequal(const char *p, const char *q) 891{ 892 while (*p == *q++) { 893 if (*p++ == '=') 894 return 1; 895 } 896 if (*p == '=' && *(q - 1) == '\0') 897 return 1; 898 return 0; 899} 900 901/* 902 * Search for a variable. 903 * 'name' may be terminated by '=' or a NUL. 904 * vppp is set to the pointer to vp, or the list head if vp isn't found 905 * lenp is set to the number of characters in 'name' 906 */ 907 908static struct var * 909find_var(const char *name, struct var ***vppp, int *lenp) 910{ 911 unsigned int hashval; 912 int len; 913 struct var *vp, **vpp; 914 const char *p = name; 915 916 hashval = 0; 917 while (*p && *p != '=') 918 hashval = 2 * hashval + (unsigned char)*p++; 919 len = p - name; 920 921 if (lenp) 922 *lenp = len; 923 vpp = &vartab[hashval % VTABSIZE]; 924 if (vppp) 925 *vppp = vpp; 926 927 for (vp = *vpp ; vp ; vpp = &vp->next, vp = *vpp) { 928 if (vp->name_len != len) 929 continue; 930 if (memcmp(vp->text, name, len) != 0) 931 continue; 932 if (vppp) 933 *vppp = vpp; 934 return vp; 935 } 936 return NULL; 937} 938