cd.c revision 12273
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 * 3612273Speter * $Id: cd.c,v 1.4 1994/12/26 13:02:05 bde 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; 9512273Speter if (dest) 9612273Speter print = 1; 9712273Speter else 9812273Speter dest = "."; 991556Srgrimes } 1001556Srgrimes if (*dest == '/' || (path = bltinlookup("CDPATH", 1)) == NULL) 1011556Srgrimes path = nullstr; 1021556Srgrimes while ((p = padvance(&path, dest)) != NULL) { 1031556Srgrimes if (stat(p, &statb) >= 0 1041556Srgrimes && (statb.st_mode & S_IFMT) == S_IFDIR) { 1051556Srgrimes if (!print) { 1061556Srgrimes /* 1071556Srgrimes * XXX - rethink 1081556Srgrimes */ 1091556Srgrimes if (p[0] == '.' && p[1] == '/') 1101556Srgrimes p += 2; 1111556Srgrimes print = strcmp(p, dest); 1121556Srgrimes } 1131556Srgrimes if (docd(p, print) >= 0) 1141556Srgrimes return 0; 1151556Srgrimes 1161556Srgrimes } 1171556Srgrimes } 1181556Srgrimes error("can't cd to %s", dest); 1191556Srgrimes} 1201556Srgrimes 1211556Srgrimes 1221556Srgrimes/* 1231556Srgrimes * Actually do the chdir. If the name refers to symbolic links, we 1241556Srgrimes * compute the actual directory name before doing the cd. In an 1251556Srgrimes * interactive shell, print the directory name if "print" is nonzero 1261556Srgrimes * or if the name refers to a symbolic link. We also print the name 1271556Srgrimes * if "/u/logname" was expanded in it, since this is similar to a 1281556Srgrimes * symbolic link. (The check for this breaks if the user gives the 1291556Srgrimes * cd command some additional, unused arguments.) 1301556Srgrimes */ 1311556Srgrimes 1321556Srgrimes#if SYMLINKS == 0 1331556SrgrimesSTATIC int 1341556Srgrimesdocd(dest, print) 1351556Srgrimes char *dest; 1361556Srgrimes { 1371556Srgrimes INTOFF; 1381556Srgrimes if (chdir(dest) < 0) { 1391556Srgrimes INTON; 1401556Srgrimes return -1; 1411556Srgrimes } 1421556Srgrimes updatepwd(dest); 1431556Srgrimes INTON; 1441556Srgrimes if (print && iflag) 1451556Srgrimes out1fmt("%s\n", stackblock()); 1461556Srgrimes return 0; 1471556Srgrimes} 1481556Srgrimes 1491556Srgrimes#else 1501556Srgrimes 1511556Srgrimes 1521556Srgrimes 1531556SrgrimesSTATIC int 1541556Srgrimesdocd(dest, print) 1551556Srgrimes char *dest; 1561556Srgrimes { 1571556Srgrimes register char *p; 1581556Srgrimes register char *q; 1591556Srgrimes char *symlink; 1601556Srgrimes char *component; 1611556Srgrimes struct stat statb; 1621556Srgrimes int first; 1631556Srgrimes int i; 1641556Srgrimes 1651556Srgrimes TRACE(("docd(\"%s\", %d) called\n", dest, print)); 1661556Srgrimes 1671556Srgrimestop: 1681556Srgrimes cdcomppath = dest; 1691556Srgrimes STARTSTACKSTR(p); 1701556Srgrimes if (*dest == '/') { 1711556Srgrimes STPUTC('/', p); 1721556Srgrimes cdcomppath++; 1731556Srgrimes } 1741556Srgrimes first = 1; 1751556Srgrimes while ((q = getcomponent()) != NULL) { 1761556Srgrimes if (q[0] == '\0' || q[0] == '.' && q[1] == '\0') 1771556Srgrimes continue; 1781556Srgrimes if (! first) 1791556Srgrimes STPUTC('/', p); 1801556Srgrimes first = 0; 1811556Srgrimes component = q; 1821556Srgrimes while (*q) 1831556Srgrimes STPUTC(*q++, p); 1841556Srgrimes if (equal(component, "..")) 1851556Srgrimes continue; 1861556Srgrimes STACKSTRNUL(p); 1871556Srgrimes if (lstat(stackblock(), &statb) < 0) 1881556Srgrimes error("lstat %s failed", stackblock()); 1891556Srgrimes if ((statb.st_mode & S_IFMT) != S_IFLNK) 1901556Srgrimes continue; 1911556Srgrimes 1921556Srgrimes /* Hit a symbolic link. We have to start all over again. */ 1931556Srgrimes print = 1; 1941556Srgrimes STPUTC('\0', p); 1951556Srgrimes symlink = grabstackstr(p); 1961556Srgrimes i = (int)statb.st_size + 2; /* 2 for '/' and '\0' */ 1971556Srgrimes if (cdcomppath != NULL) 1981556Srgrimes i += strlen(cdcomppath); 1991556Srgrimes p = stalloc(i); 2001556Srgrimes if (readlink(symlink, p, (int)statb.st_size) < 0) { 2011556Srgrimes error("readlink %s failed", stackblock()); 2021556Srgrimes } 2031556Srgrimes if (cdcomppath != NULL) { 2041556Srgrimes p[(int)statb.st_size] = '/'; 2051556Srgrimes scopy(cdcomppath, p + (int)statb.st_size + 1); 2061556Srgrimes } else { 2071556Srgrimes p[(int)statb.st_size] = '\0'; 2081556Srgrimes } 2091556Srgrimes if (p[0] != '/') { /* relative path name */ 2101556Srgrimes char *r; 2111556Srgrimes q = r = symlink; 2121556Srgrimes while (*q) { 2131556Srgrimes if (*q++ == '/') 2141556Srgrimes r = q; 2151556Srgrimes } 2161556Srgrimes *r = '\0'; 2171556Srgrimes dest = stalloc(strlen(symlink) + strlen(p) + 1); 2181556Srgrimes scopy(symlink, dest); 2191556Srgrimes strcat(dest, p); 2201556Srgrimes } else { 2211556Srgrimes dest = p; 2221556Srgrimes } 2231556Srgrimes goto top; 2241556Srgrimes } 2251556Srgrimes STPUTC('\0', p); 2261556Srgrimes p = grabstackstr(p); 2271556Srgrimes INTOFF; 2285234Sbde if (chdir(*p ? p : ".") < 0) { 2291556Srgrimes INTON; 2301556Srgrimes return -1; 2311556Srgrimes } 2321556Srgrimes updatepwd(p); 2331556Srgrimes INTON; 2341556Srgrimes if (print && iflag) 2351556Srgrimes out1fmt("%s\n", p); 2361556Srgrimes return 0; 2371556Srgrimes} 2381556Srgrimes#endif /* SYMLINKS */ 2391556Srgrimes 2401556Srgrimes 2411556Srgrimes 2421556Srgrimes/* 2431556Srgrimes * Get the next component of the path name pointed to by cdcomppath. 2441556Srgrimes * This routine overwrites the string pointed to by cdcomppath. 2451556Srgrimes */ 2461556Srgrimes 2471556SrgrimesSTATIC char * 2481556Srgrimesgetcomponent() { 2491556Srgrimes register char *p; 2501556Srgrimes char *start; 2511556Srgrimes 2521556Srgrimes if ((p = cdcomppath) == NULL) 2531556Srgrimes return NULL; 2541556Srgrimes start = cdcomppath; 2551556Srgrimes while (*p != '/' && *p != '\0') 2561556Srgrimes p++; 2571556Srgrimes if (*p == '\0') { 2581556Srgrimes cdcomppath = NULL; 2591556Srgrimes } else { 2601556Srgrimes *p++ = '\0'; 2611556Srgrimes cdcomppath = p; 2621556Srgrimes } 2631556Srgrimes return start; 2641556Srgrimes} 2651556Srgrimes 2661556Srgrimes 2671556Srgrimes 2681556Srgrimes/* 2691556Srgrimes * Update curdir (the name of the current directory) in response to a 2701556Srgrimes * cd command. We also call hashcd to let the routines in exec.c know 2711556Srgrimes * that the current directory has changed. 2721556Srgrimes */ 2731556Srgrimes 2741556Srgrimesvoid hashcd(); 2751556Srgrimes 2761556SrgrimesSTATIC void 2771556Srgrimesupdatepwd(dir) 2781556Srgrimes char *dir; 2791556Srgrimes { 2801556Srgrimes char *new; 2811556Srgrimes char *p; 2821556Srgrimes 2831556Srgrimes hashcd(); /* update command hash table */ 2841556Srgrimes cdcomppath = stalloc(strlen(dir) + 1); 2851556Srgrimes scopy(dir, cdcomppath); 2861556Srgrimes STARTSTACKSTR(new); 2871556Srgrimes if (*dir != '/') { 2881556Srgrimes if (curdir == NULL) 2891556Srgrimes return; 2901556Srgrimes p = curdir; 2911556Srgrimes while (*p) 2921556Srgrimes STPUTC(*p++, new); 2931556Srgrimes if (p[-1] == '/') 2941556Srgrimes STUNPUTC(new); 2951556Srgrimes } 2961556Srgrimes while ((p = getcomponent()) != NULL) { 2971556Srgrimes if (equal(p, "..")) { 2981556Srgrimes while (new > stackblock() && (STUNPUTC(new), *new) != '/'); 2991556Srgrimes } else if (*p != '\0' && ! equal(p, ".")) { 3001556Srgrimes STPUTC('/', new); 3011556Srgrimes while (*p) 3021556Srgrimes STPUTC(*p++, new); 3031556Srgrimes } 3041556Srgrimes } 3051556Srgrimes if (new == stackblock()) 3061556Srgrimes STPUTC('/', new); 3071556Srgrimes STACKSTRNUL(new); 3081556Srgrimes INTOFF; 3091556Srgrimes if (prevdir) 3101556Srgrimes ckfree(prevdir); 3111556Srgrimes prevdir = curdir; 3121556Srgrimes curdir = savestr(stackblock()); 3131556Srgrimes INTON; 3141556Srgrimes} 3151556Srgrimes 3161556Srgrimes 3171556Srgrimes 3181556Srgrimesint 3191556Srgrimespwdcmd(argc, argv) char **argv; { 3201556Srgrimes getpwd(); 3211556Srgrimes out1str(curdir); 3221556Srgrimes out1c('\n'); 3231556Srgrimes return 0; 3241556Srgrimes} 3251556Srgrimes 3261556Srgrimes 3271556Srgrimes 3281556Srgrimes/* 3291556Srgrimes * Run /bin/pwd to find out what the current directory is. We suppress 3301556Srgrimes * interrupts throughout most of this, but the user can still break out 3311556Srgrimes * of it by killing the pwd program. If we already know the current 3321556Srgrimes * directory, this routine returns immediately. 3331556Srgrimes */ 3341556Srgrimes 3351556Srgrimes#define MAXPWD 256 3361556Srgrimes 3371556SrgrimesSTATIC void 3381556Srgrimesgetpwd() { 3391556Srgrimes char buf[MAXPWD]; 3401556Srgrimes char *p; 3411556Srgrimes int i; 3421556Srgrimes int status; 3431556Srgrimes struct job *jp; 3441556Srgrimes int pip[2]; 3454192Sjkh char *pwd_bin = "/bin/pwd"; 3461556Srgrimes 3471556Srgrimes if (curdir) 3481556Srgrimes return; 3491556Srgrimes INTOFF; 3501556Srgrimes if (pipe(pip) < 0) 3511556Srgrimes error("Pipe call failed"); 3524192Sjkh /* make a fall-back guess, otherwise we're simply screwed */ 3534192Sjkh if (access(pwd_bin, X_OK) == -1) 3544192Sjkh pwd_bin = "/stand/pwd"; 3551556Srgrimes jp = makejob((union node *)NULL, 1); 3561556Srgrimes if (forkshell(jp, (union node *)NULL, FORK_NOJOB) == 0) { 3571556Srgrimes close(pip[0]); 3581556Srgrimes if (pip[1] != 1) { 3591556Srgrimes close(1); 3601556Srgrimes copyfd(pip[1], 1); 3611556Srgrimes close(pip[1]); 3621556Srgrimes } 3634192Sjkh execl(pwd_bin, "pwd", (char *)0); 3644192Sjkh error("Cannot exec %s", pwd_bin); 3651556Srgrimes } 3661556Srgrimes close(pip[1]); 3671556Srgrimes pip[1] = -1; 3681556Srgrimes p = buf; 3691556Srgrimes while ((i = read(pip[0], p, buf + MAXPWD - p)) > 0 3701556Srgrimes || i == -1 && errno == EINTR) { 3711556Srgrimes if (i > 0) 3721556Srgrimes p += i; 3731556Srgrimes } 3741556Srgrimes close(pip[0]); 3751556Srgrimes pip[0] = -1; 3761556Srgrimes status = waitforjob(jp); 3771556Srgrimes if (status != 0) 3781556Srgrimes error((char *)0); 3791556Srgrimes if (i < 0 || p == buf || p[-1] != '\n') 3801556Srgrimes error("pwd command failed"); 3811556Srgrimes p[-1] = '\0'; 3821556Srgrimes curdir = savestr(buf); 3831556Srgrimes INTON; 3841556Srgrimes} 385