cd.c revision 5234
11556Srgrimes/*- 21556Srgrimes * Copyright (c) 1991, 1993 31556Srgrimes * The Regents of the University of California. All rights reserved. 41556Srgrimes * 51556Srgrimes * This code is derived from software contributed to Berkeley by 61556Srgrimes * Kenneth Almquist. 71556Srgrimes * 81556Srgrimes * Redistribution and use in source and binary forms, with or without 91556Srgrimes * modification, are permitted provided that the following conditions 101556Srgrimes * are met: 111556Srgrimes * 1. Redistributions of source code must retain the above copyright 121556Srgrimes * notice, this list of conditions and the following disclaimer. 131556Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 141556Srgrimes * notice, this list of conditions and the following disclaimer in the 151556Srgrimes * documentation and/or other materials provided with the distribution. 161556Srgrimes * 3. All advertising materials mentioning features or use of this software 171556Srgrimes * must display the following acknowledgement: 181556Srgrimes * This product includes software developed by the University of 191556Srgrimes * California, Berkeley and its contributors. 201556Srgrimes * 4. Neither the name of the University nor the names of its contributors 211556Srgrimes * may be used to endorse or promote products derived from this software 221556Srgrimes * without specific prior written permission. 231556Srgrimes * 241556Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 251556Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 261556Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 271556Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 281556Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 291556Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 301556Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 311556Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 321556Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 331556Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 341556Srgrimes * SUCH DAMAGE. 353044Sdg * 365234Sbde * $Id: cd.c,v 1.3 1994/11/06 01:29:26 jkh Exp $ 371556Srgrimes */ 381556Srgrimes 391556Srgrimes#ifndef lint 401556Srgrimesstatic char sccsid[] = "@(#)cd.c 8.1 (Berkeley) 5/31/93"; 411556Srgrimes#endif /* not lint */ 421556Srgrimes 431556Srgrimes/* 441556Srgrimes * The cd and pwd commands. 451556Srgrimes */ 461556Srgrimes 471556Srgrimes#include "shell.h" 481556Srgrimes#include "var.h" 491556Srgrimes#include "nodes.h" /* for jobs.h */ 501556Srgrimes#include "jobs.h" 511556Srgrimes#include "options.h" 521556Srgrimes#include "output.h" 531556Srgrimes#include "memalloc.h" 541556Srgrimes#include "error.h" 551556Srgrimes#include "mystring.h" 561556Srgrimes#include <sys/types.h> 571556Srgrimes#include <sys/stat.h> 584192Sjkh#include <sys/unistd.h> 591556Srgrimes#include <errno.h> 601556Srgrimes 611556Srgrimes 621556Srgrimes#ifdef __STDC__ 631556SrgrimesSTATIC int docd(char *, int); 641556SrgrimesSTATIC void updatepwd(char *); 651556SrgrimesSTATIC void getpwd(void); 661556SrgrimesSTATIC char *getcomponent(void); 671556Srgrimes#else 681556SrgrimesSTATIC int docd(); 691556SrgrimesSTATIC void updatepwd(); 701556SrgrimesSTATIC void getpwd(); 711556SrgrimesSTATIC char *getcomponent(); 721556Srgrimes#endif 731556Srgrimes 741556Srgrimes 751556Srgrimeschar *curdir; /* current working directory */ 761556Srgrimeschar *prevdir; /* previous working directory */ 771556SrgrimesSTATIC char *cdcomppath; 781556Srgrimes 791556Srgrimesint 801556Srgrimescdcmd(argc, argv) char **argv; { 811556Srgrimes char *dest; 821556Srgrimes char *path; 831556Srgrimes char *p; 841556Srgrimes struct stat statb; 851556Srgrimes char *padvance(); 861556Srgrimes int print = 0; 871556Srgrimes 881556Srgrimes nextopt(nullstr); 891556Srgrimes if ((dest = *argptr) == NULL && (dest = bltinlookup("HOME", 1)) == NULL) 901556Srgrimes error("HOME not set"); 915234Sbde if (*dest == '\0') 925234Sbde dest = "."; 931556Srgrimes if (dest[0] == '-' && dest[1] == '\0') { 941556Srgrimes dest = prevdir ? prevdir : curdir; 951556Srgrimes print = 1; 961556Srgrimes } 971556Srgrimes if (*dest == '/' || (path = bltinlookup("CDPATH", 1)) == NULL) 981556Srgrimes path = nullstr; 991556Srgrimes while ((p = padvance(&path, dest)) != NULL) { 1001556Srgrimes if (stat(p, &statb) >= 0 1011556Srgrimes && (statb.st_mode & S_IFMT) == S_IFDIR) { 1021556Srgrimes if (!print) { 1031556Srgrimes /* 1041556Srgrimes * XXX - rethink 1051556Srgrimes */ 1061556Srgrimes if (p[0] == '.' && p[1] == '/') 1071556Srgrimes p += 2; 1081556Srgrimes print = strcmp(p, dest); 1091556Srgrimes } 1101556Srgrimes if (docd(p, print) >= 0) 1111556Srgrimes return 0; 1121556Srgrimes 1131556Srgrimes } 1141556Srgrimes } 1151556Srgrimes error("can't cd to %s", dest); 1161556Srgrimes} 1171556Srgrimes 1181556Srgrimes 1191556Srgrimes/* 1201556Srgrimes * Actually do the chdir. If the name refers to symbolic links, we 1211556Srgrimes * compute the actual directory name before doing the cd. In an 1221556Srgrimes * interactive shell, print the directory name if "print" is nonzero 1231556Srgrimes * or if the name refers to a symbolic link. We also print the name 1241556Srgrimes * if "/u/logname" was expanded in it, since this is similar to a 1251556Srgrimes * symbolic link. (The check for this breaks if the user gives the 1261556Srgrimes * cd command some additional, unused arguments.) 1271556Srgrimes */ 1281556Srgrimes 1291556Srgrimes#if SYMLINKS == 0 1301556SrgrimesSTATIC int 1311556Srgrimesdocd(dest, print) 1321556Srgrimes char *dest; 1331556Srgrimes { 1341556Srgrimes INTOFF; 1351556Srgrimes if (chdir(dest) < 0) { 1361556Srgrimes INTON; 1371556Srgrimes return -1; 1381556Srgrimes } 1391556Srgrimes updatepwd(dest); 1401556Srgrimes INTON; 1411556Srgrimes if (print && iflag) 1421556Srgrimes out1fmt("%s\n", stackblock()); 1431556Srgrimes return 0; 1441556Srgrimes} 1451556Srgrimes 1461556Srgrimes#else 1471556Srgrimes 1481556Srgrimes 1491556Srgrimes 1501556SrgrimesSTATIC int 1511556Srgrimesdocd(dest, print) 1521556Srgrimes char *dest; 1531556Srgrimes { 1541556Srgrimes register char *p; 1551556Srgrimes register char *q; 1561556Srgrimes char *symlink; 1571556Srgrimes char *component; 1581556Srgrimes struct stat statb; 1591556Srgrimes int first; 1601556Srgrimes int i; 1611556Srgrimes 1621556Srgrimes TRACE(("docd(\"%s\", %d) called\n", dest, print)); 1631556Srgrimes 1641556Srgrimestop: 1651556Srgrimes cdcomppath = dest; 1661556Srgrimes STARTSTACKSTR(p); 1671556Srgrimes if (*dest == '/') { 1681556Srgrimes STPUTC('/', p); 1691556Srgrimes cdcomppath++; 1701556Srgrimes } 1711556Srgrimes first = 1; 1721556Srgrimes while ((q = getcomponent()) != NULL) { 1731556Srgrimes if (q[0] == '\0' || q[0] == '.' && q[1] == '\0') 1741556Srgrimes continue; 1751556Srgrimes if (! first) 1761556Srgrimes STPUTC('/', p); 1771556Srgrimes first = 0; 1781556Srgrimes component = q; 1791556Srgrimes while (*q) 1801556Srgrimes STPUTC(*q++, p); 1811556Srgrimes if (equal(component, "..")) 1821556Srgrimes continue; 1831556Srgrimes STACKSTRNUL(p); 1841556Srgrimes if (lstat(stackblock(), &statb) < 0) 1851556Srgrimes error("lstat %s failed", stackblock()); 1861556Srgrimes if ((statb.st_mode & S_IFMT) != S_IFLNK) 1871556Srgrimes continue; 1881556Srgrimes 1891556Srgrimes /* Hit a symbolic link. We have to start all over again. */ 1901556Srgrimes print = 1; 1911556Srgrimes STPUTC('\0', p); 1921556Srgrimes symlink = grabstackstr(p); 1931556Srgrimes i = (int)statb.st_size + 2; /* 2 for '/' and '\0' */ 1941556Srgrimes if (cdcomppath != NULL) 1951556Srgrimes i += strlen(cdcomppath); 1961556Srgrimes p = stalloc(i); 1971556Srgrimes if (readlink(symlink, p, (int)statb.st_size) < 0) { 1981556Srgrimes error("readlink %s failed", stackblock()); 1991556Srgrimes } 2001556Srgrimes if (cdcomppath != NULL) { 2011556Srgrimes p[(int)statb.st_size] = '/'; 2021556Srgrimes scopy(cdcomppath, p + (int)statb.st_size + 1); 2031556Srgrimes } else { 2041556Srgrimes p[(int)statb.st_size] = '\0'; 2051556Srgrimes } 2061556Srgrimes if (p[0] != '/') { /* relative path name */ 2071556Srgrimes char *r; 2081556Srgrimes q = r = symlink; 2091556Srgrimes while (*q) { 2101556Srgrimes if (*q++ == '/') 2111556Srgrimes r = q; 2121556Srgrimes } 2131556Srgrimes *r = '\0'; 2141556Srgrimes dest = stalloc(strlen(symlink) + strlen(p) + 1); 2151556Srgrimes scopy(symlink, dest); 2161556Srgrimes strcat(dest, p); 2171556Srgrimes } else { 2181556Srgrimes dest = p; 2191556Srgrimes } 2201556Srgrimes goto top; 2211556Srgrimes } 2221556Srgrimes STPUTC('\0', p); 2231556Srgrimes p = grabstackstr(p); 2241556Srgrimes INTOFF; 2255234Sbde if (chdir(*p ? p : ".") < 0) { 2261556Srgrimes INTON; 2271556Srgrimes return -1; 2281556Srgrimes } 2291556Srgrimes updatepwd(p); 2301556Srgrimes INTON; 2311556Srgrimes if (print && iflag) 2321556Srgrimes out1fmt("%s\n", p); 2331556Srgrimes return 0; 2341556Srgrimes} 2351556Srgrimes#endif /* SYMLINKS */ 2361556Srgrimes 2371556Srgrimes 2381556Srgrimes 2391556Srgrimes/* 2401556Srgrimes * Get the next component of the path name pointed to by cdcomppath. 2411556Srgrimes * This routine overwrites the string pointed to by cdcomppath. 2421556Srgrimes */ 2431556Srgrimes 2441556SrgrimesSTATIC char * 2451556Srgrimesgetcomponent() { 2461556Srgrimes register char *p; 2471556Srgrimes char *start; 2481556Srgrimes 2491556Srgrimes if ((p = cdcomppath) == NULL) 2501556Srgrimes return NULL; 2511556Srgrimes start = cdcomppath; 2521556Srgrimes while (*p != '/' && *p != '\0') 2531556Srgrimes p++; 2541556Srgrimes if (*p == '\0') { 2551556Srgrimes cdcomppath = NULL; 2561556Srgrimes } else { 2571556Srgrimes *p++ = '\0'; 2581556Srgrimes cdcomppath = p; 2591556Srgrimes } 2601556Srgrimes return start; 2611556Srgrimes} 2621556Srgrimes 2631556Srgrimes 2641556Srgrimes 2651556Srgrimes/* 2661556Srgrimes * Update curdir (the name of the current directory) in response to a 2671556Srgrimes * cd command. We also call hashcd to let the routines in exec.c know 2681556Srgrimes * that the current directory has changed. 2691556Srgrimes */ 2701556Srgrimes 2711556Srgrimesvoid hashcd(); 2721556Srgrimes 2731556SrgrimesSTATIC void 2741556Srgrimesupdatepwd(dir) 2751556Srgrimes char *dir; 2761556Srgrimes { 2771556Srgrimes char *new; 2781556Srgrimes char *p; 2791556Srgrimes 2801556Srgrimes hashcd(); /* update command hash table */ 2811556Srgrimes cdcomppath = stalloc(strlen(dir) + 1); 2821556Srgrimes scopy(dir, cdcomppath); 2831556Srgrimes STARTSTACKSTR(new); 2841556Srgrimes if (*dir != '/') { 2851556Srgrimes if (curdir == NULL) 2861556Srgrimes return; 2871556Srgrimes p = curdir; 2881556Srgrimes while (*p) 2891556Srgrimes STPUTC(*p++, new); 2901556Srgrimes if (p[-1] == '/') 2911556Srgrimes STUNPUTC(new); 2921556Srgrimes } 2931556Srgrimes while ((p = getcomponent()) != NULL) { 2941556Srgrimes if (equal(p, "..")) { 2951556Srgrimes while (new > stackblock() && (STUNPUTC(new), *new) != '/'); 2961556Srgrimes } else if (*p != '\0' && ! equal(p, ".")) { 2971556Srgrimes STPUTC('/', new); 2981556Srgrimes while (*p) 2991556Srgrimes STPUTC(*p++, new); 3001556Srgrimes } 3011556Srgrimes } 3021556Srgrimes if (new == stackblock()) 3031556Srgrimes STPUTC('/', new); 3041556Srgrimes STACKSTRNUL(new); 3051556Srgrimes INTOFF; 3061556Srgrimes if (prevdir) 3071556Srgrimes ckfree(prevdir); 3081556Srgrimes prevdir = curdir; 3091556Srgrimes curdir = savestr(stackblock()); 3101556Srgrimes INTON; 3111556Srgrimes} 3121556Srgrimes 3131556Srgrimes 3141556Srgrimes 3151556Srgrimesint 3161556Srgrimespwdcmd(argc, argv) char **argv; { 3171556Srgrimes getpwd(); 3181556Srgrimes out1str(curdir); 3191556Srgrimes out1c('\n'); 3201556Srgrimes return 0; 3211556Srgrimes} 3221556Srgrimes 3231556Srgrimes 3241556Srgrimes 3251556Srgrimes/* 3261556Srgrimes * Run /bin/pwd to find out what the current directory is. We suppress 3271556Srgrimes * interrupts throughout most of this, but the user can still break out 3281556Srgrimes * of it by killing the pwd program. If we already know the current 3291556Srgrimes * directory, this routine returns immediately. 3301556Srgrimes */ 3311556Srgrimes 3321556Srgrimes#define MAXPWD 256 3331556Srgrimes 3341556SrgrimesSTATIC void 3351556Srgrimesgetpwd() { 3361556Srgrimes char buf[MAXPWD]; 3371556Srgrimes char *p; 3381556Srgrimes int i; 3391556Srgrimes int status; 3401556Srgrimes struct job *jp; 3411556Srgrimes int pip[2]; 3424192Sjkh char *pwd_bin = "/bin/pwd"; 3431556Srgrimes 3441556Srgrimes if (curdir) 3451556Srgrimes return; 3461556Srgrimes INTOFF; 3471556Srgrimes if (pipe(pip) < 0) 3481556Srgrimes error("Pipe call failed"); 3494192Sjkh /* make a fall-back guess, otherwise we're simply screwed */ 3504192Sjkh if (access(pwd_bin, X_OK) == -1) 3514192Sjkh pwd_bin = "/stand/pwd"; 3521556Srgrimes jp = makejob((union node *)NULL, 1); 3531556Srgrimes if (forkshell(jp, (union node *)NULL, FORK_NOJOB) == 0) { 3541556Srgrimes close(pip[0]); 3551556Srgrimes if (pip[1] != 1) { 3561556Srgrimes close(1); 3571556Srgrimes copyfd(pip[1], 1); 3581556Srgrimes close(pip[1]); 3591556Srgrimes } 3604192Sjkh execl(pwd_bin, "pwd", (char *)0); 3614192Sjkh error("Cannot exec %s", pwd_bin); 3621556Srgrimes } 3631556Srgrimes close(pip[1]); 3641556Srgrimes pip[1] = -1; 3651556Srgrimes p = buf; 3661556Srgrimes while ((i = read(pip[0], p, buf + MAXPWD - p)) > 0 3671556Srgrimes || i == -1 && errno == EINTR) { 3681556Srgrimes if (i > 0) 3691556Srgrimes p += i; 3701556Srgrimes } 3711556Srgrimes close(pip[0]); 3721556Srgrimes pip[0] = -1; 3731556Srgrimes status = waitforjob(jp); 3741556Srgrimes if (status != 0) 3751556Srgrimes error((char *)0); 3761556Srgrimes if (i < 0 || p == buf || p[-1] != '\n') 3771556Srgrimes error("pwd command failed"); 3781556Srgrimes p[-1] = '\0'; 3791556Srgrimes curdir = savestr(buf); 3801556Srgrimes INTON; 3811556Srgrimes} 382