cd.c revision 199631
167761Smsmith/*- 267761Smsmith * Copyright (c) 1991, 1993 367761Smsmith * The Regents of the University of California. All rights reserved. 467761Smsmith * 567761Smsmith * This code is derived from software contributed to Berkeley by 667761Smsmith * Kenneth Almquist. 767761Smsmith * 867761Smsmith * Redistribution and use in source and binary forms, with or without 967761Smsmith * modification, are permitted provided that the following conditions 1067761Smsmith * are met: 1167761Smsmith * 1. Redistributions of source code must retain the above copyright 1267761Smsmith * notice, this list of conditions and the following disclaimer. 1367761Smsmith * 2. Redistributions in binary form must reproduce the above copyright 1467761Smsmith * notice, this list of conditions and the following disclaimer in the 1567761Smsmith * documentation and/or other materials provided with the distribution. 1667761Smsmith * 4. Neither the name of the University nor the names of its contributors 1767761Smsmith * may be used to endorse or promote products derived from this software 1867761Smsmith * without specific prior written permission. 1967761Smsmith * 2067761Smsmith * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 2167761Smsmith * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2267761Smsmith * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2367761Smsmith * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2467761Smsmith * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2567761Smsmith * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2667761Smsmith * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2767761Smsmith * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2867761Smsmith * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2967761Smsmith * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30119418Sobrien * SUCH DAMAGE. 31119418Sobrien */ 32119418Sobrien 3367761Smsmith#ifndef lint 3467761Smsmith#if 0 3567761Smsmithstatic char sccsid[] = "@(#)cd.c 8.2 (Berkeley) 5/4/95"; 36129879Sphk#endif 3767761Smsmith#endif /* not lint */ 3874914Sjhb#include <sys/cdefs.h> 3967761Smsmith__FBSDID("$FreeBSD: head/bin/sh/cd.c 199631 2009-11-21 14:53:22Z stefanf $"); 40193530Sjkim 41193530Sjkim#include <sys/types.h> 42193530Sjkim#include <sys/stat.h> 4367761Smsmith#include <stdlib.h> 4467761Smsmith#include <string.h> 45119529Snjl#include <unistd.h> 4677432Smsmith#include <errno.h> 4791123Smsmith#include <limits.h> 4869744Smsmith 4967761Smsmith/* 5067761Smsmith * The cd and pwd commands. 5167761Smsmith */ 5267761Smsmith 5367761Smsmith#include "shell.h" 5467761Smsmith#include "var.h" 55133618Snjl#include "nodes.h" /* for jobs.h */ 56133618Snjl#include "jobs.h" 5767761Smsmith#include "options.h" 5867761Smsmith#include "output.h" 59100497Siwasaki#include "memalloc.h" 60100497Siwasaki#include "error.h" 6167761Smsmith#include "exec.h" 62121493Snjl#include "redir.h" 63121493Snjl#include "mystring.h" 6467761Smsmith#include "show.h" 6567761Smsmith#include "cd.h" 6667761Smsmith 6767761SmsmithSTATIC int cdlogical(char *); 6867761SmsmithSTATIC int cdphysical(char *); 69100497SiwasakiSTATIC int docd(char *, int, int); 70100497SiwasakiSTATIC char *getcomponent(void); 7167761SmsmithSTATIC char *findcwd(char *); 72246128SsbzSTATIC void updatepwd(char *); 7367761SmsmithSTATIC char *getpwd2(void); 7467761Smsmith 7567761SmsmithSTATIC char *curdir = NULL; /* current working directory */ 7667761SmsmithSTATIC char *prevdir; /* previous working directory */ 7767761SmsmithSTATIC char *cdcomppath; 7867761Smsmith 7967761Smsmithint 8067761Smsmithcdcmd(int argc, char **argv) 8189054Smsmith{ 8267761Smsmith char *dest; 83128071Snjl char *path; 8467761Smsmith char *p; 8567761Smsmith struct stat statb; 8667761Smsmith int ch, phys, print = 0; 8767761Smsmith 88131282Snjl optreset = 1; optind = 1; opterr = 0; /* initialize getopt */ 89119529Snjl phys = Pflag; 90131282Snjl while ((ch = getopt(argc, argv, "LP")) != -1) { 91131282Snjl switch (ch) { 92131282Snjl case 'L': 93131282Snjl phys = 0; 94131282Snjl break; 95131282Snjl case 'P': 9667761Smsmith phys = 1; 9767761Smsmith break; 9867761Smsmith default: 9967761Smsmith error("unknown option: -%c", optopt); 10067761Smsmith break; 101209746Sjkim } 10267761Smsmith } 10367761Smsmith argc -= optind; 10496926Speter argv += optind; 10569744Smsmith 10667761Smsmith if (argc > 1) 10767761Smsmith error("too many arguments"); 10867761Smsmith 10967761Smsmith if ((dest = *argv) == NULL && (dest = bltinlookup("HOME", 1)) == NULL) 110129692Snjl error("HOME not set"); 111129692Snjl if (*dest == '\0') 112129692Snjl dest = "."; 113129692Snjl if (dest[0] == '-' && dest[1] == '\0') { 114129692Snjl dest = prevdir ? prevdir : curdir; 115119529Snjl if (dest) 116119529Snjl print = 1; 117119529Snjl else 118129783Snjl dest = "."; 119129783Snjl } 120209746Sjkim if (*dest == '/' || (path = bltinlookup("CDPATH", 1)) == NULL) 121209746Sjkim path = nullstr; 122129783Snjl while ((p = padvance(&path, dest)) != NULL) { 123133618Snjl if (stat(p, &statb) >= 0 && S_ISDIR(statb.st_mode)) { 12467761Smsmith if (!print) { 12567761Smsmith /* 126100497Siwasaki * XXX - rethink 127100497Siwasaki */ 128100497Siwasaki if (p[0] == '.' && p[1] == '/' && p[2] != '\0') 129100497Siwasaki print = strcmp(p + 2, dest); 130100497Siwasaki else 131100497Siwasaki print = strcmp(p, dest); 132100497Siwasaki } 133100497Siwasaki if (docd(p, print, phys) >= 0) 134100497Siwasaki return 0; 135100497Siwasaki } 136100497Siwasaki } 137100497Siwasaki error("can't cd to %s", dest); 13867761Smsmith /*NOTREACHED*/ 13967761Smsmith return 0; 14067761Smsmith} 14167761Smsmith 14267761Smsmith 143119529Snjl/* 14467761Smsmith * Actually change the directory. In an interactive shell, print the 14596926Speter * directory name if "print" is nonzero. 14669744Smsmith */ 14767761SmsmithSTATIC int 148134305Snjldocd(char *dest, int print, int phys) 14967761Smsmith{ 15067761Smsmith 15171872Smsmith TRACE(("docd(\"%s\", %d, %d) called\n", dest, print, phys)); 15267761Smsmith 15367761Smsmith /* If logical cd fails, fall back to physical. */ 15467761Smsmith if ((phys || cdlogical(dest) < 0) && cdphysical(dest) < 0) 155134305Snjl return (-1); 156119529Snjl 157134305Snjl if (print && iflag && curdir) 15867761Smsmith out1fmt("%s\n", curdir); 159134305Snjl 160134305Snjl return 0; 161134305Snjl} 16267761Smsmith 163134305SnjlSTATIC int 164134305Snjlcdlogical(char *dest) 16586552Siwasaki{ 166134305Snjl char *p; 167121493Snjl char *q; 168134305Snjl char *component; 169134305Snjl struct stat statb; 170134305Snjl int first; 171134305Snjl int badstat; 172134305Snjl 173133618Snjl /* 174133618Snjl * Check each component of the path. If we find a symlink or 17569744Smsmith * something we can't stat, clear curdir to force a getcwd() 17667761Smsmith * next time we get the value of the current directory. 17767761Smsmith */ 17867761Smsmith badstat = 0; 17967761Smsmith cdcomppath = stalloc(strlen(dest) + 1); 18067761Smsmith scopy(dest, cdcomppath); 18167761Smsmith STARTSTACKSTR(p); 18267761Smsmith if (*dest == '/') { 18367761Smsmith STPUTC('/', p); 184129692Snjl cdcomppath++; 18567761Smsmith } 18696926Speter first = 1; 18769744Smsmith while ((q = getcomponent()) != NULL) { 188129692Snjl if (q[0] == '\0' || (q[0] == '.' && q[1] == '\0')) 18967761Smsmith continue; 19067761Smsmith if (! first) 191167814Sjkim STPUTC('/', p); 192167814Sjkim first = 0; 19367761Smsmith component = q; 19467761Smsmith while (*q) 195129692Snjl STPUTC(*q++, p); 196119529Snjl if (equal(component, "..")) 19767761Smsmith continue; 198119529Snjl STACKSTRNUL(p); 19969744Smsmith if (lstat(stackblock(), &statb) < 0) { 20067761Smsmith badstat = 1; 201 break; 202 } 203 } 204 205 INTOFF; 206 if ((p = findcwd(badstat ? NULL : dest)) == NULL || chdir(p) < 0) { 207 INTON; 208 return (-1); 209 } 210 updatepwd(p); 211 INTON; 212 return (0); 213} 214 215STATIC int 216cdphysical(char *dest) 217{ 218 char *p; 219 220 INTOFF; 221 if (chdir(dest) < 0 || (p = findcwd(NULL)) == NULL) { 222 INTON; 223 return (-1); 224 } 225 updatepwd(p); 226 INTON; 227 return (0); 228} 229 230/* 231 * Get the next component of the path name pointed to by cdcomppath. 232 * This routine overwrites the string pointed to by cdcomppath. 233 */ 234STATIC char * 235getcomponent(void) 236{ 237 char *p; 238 char *start; 239 240 if ((p = cdcomppath) == NULL) 241 return NULL; 242 start = cdcomppath; 243 while (*p != '/' && *p != '\0') 244 p++; 245 if (*p == '\0') { 246 cdcomppath = NULL; 247 } else { 248 *p++ = '\0'; 249 cdcomppath = p; 250 } 251 return start; 252} 253 254 255STATIC char * 256findcwd(char *dir) 257{ 258 char *new; 259 char *p; 260 261 /* 262 * If our argument is NULL, we don't know the current directory 263 * any more because we traversed a symbolic link or something 264 * we couldn't stat(). 265 */ 266 if (dir == NULL || curdir == NULL) 267 return getpwd2(); 268 cdcomppath = stalloc(strlen(dir) + 1); 269 scopy(dir, cdcomppath); 270 STARTSTACKSTR(new); 271 if (*dir != '/') { 272 p = curdir; 273 while (*p) 274 STPUTC(*p++, new); 275 if (p[-1] == '/') 276 STUNPUTC(new); 277 } 278 while ((p = getcomponent()) != NULL) { 279 if (equal(p, "..")) { 280 while (new > stackblock() && (STUNPUTC(new), *new) != '/'); 281 } else if (*p != '\0' && ! equal(p, ".")) { 282 STPUTC('/', new); 283 while (*p) 284 STPUTC(*p++, new); 285 } 286 } 287 if (new == stackblock()) 288 STPUTC('/', new); 289 STACKSTRNUL(new); 290 return stackblock(); 291} 292 293/* 294 * Update curdir (the name of the current directory) in response to a 295 * cd command. We also call hashcd to let the routines in exec.c know 296 * that the current directory has changed. 297 */ 298STATIC void 299updatepwd(char *dir) 300{ 301 hashcd(); /* update command hash table */ 302 303 if (prevdir) 304 ckfree(prevdir); 305 prevdir = curdir; 306 curdir = savestr(dir); 307 setvar("PWD", curdir, VEXPORT); 308 setvar("OLDPWD", prevdir, VEXPORT); 309} 310 311int 312pwdcmd(int argc, char **argv) 313{ 314 char *p; 315 int ch, phys; 316 317 optreset = 1; optind = 1; opterr = 0; /* initialize getopt */ 318 phys = Pflag; 319 while ((ch = getopt(argc, argv, "LP")) != -1) { 320 switch (ch) { 321 case 'L': 322 phys = 0; 323 break; 324 case 'P': 325 phys = 1; 326 break; 327 default: 328 error("unknown option: -%c", optopt); 329 break; 330 } 331 } 332 argc -= optind; 333 argv += optind; 334 335 if (argc != 0) 336 error("too many arguments"); 337 338 if (!phys && getpwd()) { 339 out1str(curdir); 340 out1c('\n'); 341 } else { 342 if ((p = getpwd2()) == NULL) 343 error(".: %s", strerror(errno)); 344 out1str(p); 345 out1c('\n'); 346 } 347 348 return 0; 349} 350 351/* 352 * Get the current directory and cache the result in curdir. 353 */ 354char * 355getpwd(void) 356{ 357 char *p; 358 359 if (curdir) 360 return curdir; 361 362 p = getpwd2(); 363 if (p != NULL) 364 curdir = savestr(p); 365 366 return curdir; 367} 368 369#define MAXPWD 256 370 371/* 372 * Return the current directory. 373 */ 374STATIC char * 375getpwd2(void) 376{ 377 struct stat stdot, stpwd; 378 char *pwd; 379 int i; 380 381 for (i = MAXPWD;; i *= 2) { 382 pwd = stalloc(i); 383 if (getcwd(pwd, i) != NULL) 384 return pwd; 385 stunalloc(pwd); 386 if (errno != ERANGE) 387 break; 388 } 389 390 pwd = getenv("PWD"); 391 if (pwd && *pwd == '/' && stat(".", &stdot) != -1 && 392 stat(pwd, &stpwd) != -1 && 393 stdot.st_dev == stpwd.st_dev && 394 stdot.st_ino == stpwd.st_ino) { 395 return pwd; 396 } 397 return NULL; 398} 399