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Diffstat (limited to 'bin/1sh/cd.c')
| -rw-r--r-- | bin/1sh/cd.c | 430 |
1 files changed, 430 insertions, 0 deletions
diff --git a/bin/1sh/cd.c b/bin/1sh/cd.c new file mode 100644 index 00000000..de1350dc --- /dev/null +++ b/bin/1sh/cd.c @@ -0,0 +1,430 @@ +/*- + * Copyright (c) 1991, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Kenneth Almquist. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#ifndef lint +#if 0 +static char sccsid[] = "@(#)cd.c 8.2 (Berkeley) 5/4/95"; +#endif +#endif /* not lint */ +#include <sys/cdefs.h> +__FBSDID("$FreeBSD: releng/12.1/bin/sh/cd.c 336320 2018-07-15 21:55:17Z jilles $"); + +#include <sys/types.h> +#include <sys/stat.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <errno.h> +#include <limits.h> + +/* + * The cd and pwd commands. + */ + +#include "shell.h" +#include "var.h" +#include "nodes.h" /* for jobs.h */ +#include "jobs.h" +#include "options.h" +#include "output.h" +#include "memalloc.h" +#include "error.h" +#include "exec.h" +#include "redir.h" +#include "mystring.h" +#include "show.h" +#include "cd.h" +#include "builtins.h" + +static int cdlogical(char *); +static int cdphysical(char *); +static int docd(char *, int, int); +static char *getcomponent(char **); +static char *findcwd(char *); +static void updatepwd(char *); +static char *getpwd(void); +static char *getpwd2(void); + +static char *curdir = NULL; /* current working directory */ + +int +cdcmd(int argc __unused, char **argv __unused) +{ + const char *dest; + const char *path; + char *p; + struct stat statb; + int ch, phys, print = 0, getcwderr = 0; + int rc; + int errno1 = ENOENT; + + phys = Pflag; + while ((ch = nextopt("eLP")) != '\0') { + switch (ch) { + case 'e': + getcwderr = 1; + break; + case 'L': + phys = 0; + break; + case 'P': + phys = 1; + break; + } + } + + if (*argptr != NULL && argptr[1] != NULL) + error("too many arguments"); + + if ((dest = *argptr) == NULL && (dest = bltinlookup("HOME", 1)) == NULL) + error("HOME not set"); + if (*dest == '\0') + dest = "."; + if (dest[0] == '-' && dest[1] == '\0') { + dest = bltinlookup("OLDPWD", 1); + if (dest == NULL) + error("OLDPWD not set"); + print = 1; + } + if (dest[0] == '/' || + (dest[0] == '.' && (dest[1] == '/' || dest[1] == '\0')) || + (dest[0] == '.' && dest[1] == '.' && (dest[2] == '/' || dest[2] == '\0')) || + (path = bltinlookup("CDPATH", 1)) == NULL) + path = ""; + while ((p = padvance(&path, NULL, dest)) != NULL) { + if (stat(p, &statb) < 0) { + if (errno != ENOENT) + errno1 = errno; + } else if (!S_ISDIR(statb.st_mode)) + errno1 = ENOTDIR; + else { + if (!print) { + /* + * XXX - rethink + */ + if (p[0] == '.' && p[1] == '/' && p[2] != '\0') + print = strcmp(p + 2, dest); + else + print = strcmp(p, dest); + } + rc = docd(p, print, phys); + if (rc >= 0) + return getcwderr ? rc : 0; + if (errno != ENOENT) + errno1 = errno; + } + } + error("%s: %s", dest, strerror(errno1)); + /*NOTREACHED*/ + return 0; +} + + +/* + * Actually change the directory. In an interactive shell, print the + * directory name if "print" is nonzero. + */ +static int +docd(char *dest, int print, int phys) +{ + int rc; + + TRACE(("docd(\"%s\", %d, %d) called\n", dest, print, phys)); + + /* If logical cd fails, fall back to physical. */ + if ((phys || (rc = cdlogical(dest)) < 0) && (rc = cdphysical(dest)) < 0) + return (-1); + + if (print && iflag && curdir) { + out1fmt("%s\n", curdir); + /* + * Ignore write errors to preserve the invariant that the + * current directory is changed iff the exit status is 0 + * (or 1 if -e was given and the full pathname could not be + * determined). + */ + flushout(out1); + outclearerror(out1); + } + + return (rc); +} + +static int +cdlogical(char *dest) +{ + char *p; + char *q; + char *component; + char *path; + struct stat statb; + int first; + int badstat; + + /* + * Check each component of the path. If we find a symlink or + * something we can't stat, clear curdir to force a getcwd() + * next time we get the value of the current directory. + */ + badstat = 0; + path = stsavestr(dest); + STARTSTACKSTR(p); + if (*dest == '/') { + STPUTC('/', p); + path++; + } + first = 1; + while ((q = getcomponent(&path)) != NULL) { + if (q[0] == '\0' || (q[0] == '.' && q[1] == '\0')) + continue; + if (! first) + STPUTC('/', p); + first = 0; + component = q; + STPUTS(q, p); + if (equal(component, "..")) + continue; + STACKSTRNUL(p); + if (lstat(stackblock(), &statb) < 0) { + badstat = 1; + break; + } + } + + INTOFF; + if ((p = findcwd(badstat ? NULL : dest)) == NULL || chdir(p) < 0) { + INTON; + return (-1); + } + updatepwd(p); + INTON; + return (0); +} + +static int +cdphysical(char *dest) +{ + char *p; + int rc = 0; + + INTOFF; + if (chdir(dest) < 0) { + INTON; + return (-1); + } + p = findcwd(NULL); + if (p == NULL) { + warning("warning: failed to get name of current directory"); + rc = 1; + } + updatepwd(p); + INTON; + return (rc); +} + +/* + * Get the next component of the path name pointed to by *path. + * This routine overwrites *path and the string pointed to by it. + */ +static char * +getcomponent(char **path) +{ + char *p; + char *start; + + if ((p = *path) == NULL) + return NULL; + start = *path; + while (*p != '/' && *p != '\0') + p++; + if (*p == '\0') { + *path = NULL; + } else { + *p++ = '\0'; + *path = p; + } + return start; +} + + +static char * +findcwd(char *dir) +{ + char *new; + char *p; + char *path; + + /* + * If our argument is NULL, we don't know the current directory + * any more because we traversed a symbolic link or something + * we couldn't stat(). + */ + if (dir == NULL || curdir == NULL) + return getpwd2(); + path = stsavestr(dir); + STARTSTACKSTR(new); + if (*dir != '/') { + STPUTS(curdir, new); + if (STTOPC(new) == '/') + STUNPUTC(new); + } + while ((p = getcomponent(&path)) != NULL) { + if (equal(p, "..")) { + while (new > stackblock() && (STUNPUTC(new), *new) != '/'); + } else if (*p != '\0' && ! equal(p, ".")) { + STPUTC('/', new); + STPUTS(p, new); + } + } + if (new == stackblock()) + STPUTC('/', new); + STACKSTRNUL(new); + return stackblock(); +} + +/* + * Update curdir (the name of the current directory) in response to a + * cd command. We also call hashcd to let the routines in exec.c know + * that the current directory has changed. + */ +static void +updatepwd(char *dir) +{ + char *prevdir; + + hashcd(); /* update command hash table */ + + setvar("PWD", dir, VEXPORT); + setvar("OLDPWD", curdir, VEXPORT); + prevdir = curdir; + curdir = dir ? savestr(dir) : NULL; + ckfree(prevdir); +} + +int +pwdcmd(int argc __unused, char **argv __unused) +{ + char *p; + int ch, phys; + + phys = Pflag; + while ((ch = nextopt("LP")) != '\0') { + switch (ch) { + case 'L': + phys = 0; + break; + case 'P': + phys = 1; + break; + } + } + + if (*argptr != NULL) + error("too many arguments"); + + if (!phys && getpwd()) { + out1str(curdir); + out1c('\n'); + } else { + if ((p = getpwd2()) == NULL) + error(".: %s", strerror(errno)); + out1str(p); + out1c('\n'); + } + + return 0; +} + +/* + * Get the current directory and cache the result in curdir. + */ +static char * +getpwd(void) +{ + char *p; + + if (curdir) + return curdir; + + p = getpwd2(); + if (p != NULL) + curdir = savestr(p); + + return curdir; +} + +#define MAXPWD 256 + +/* + * Return the current directory. + */ +static char * +getpwd2(void) +{ + char *pwd; + int i; + + for (i = MAXPWD;; i *= 2) { + pwd = stalloc(i); + if (getcwd(pwd, i) != NULL) + return pwd; + stunalloc(pwd); + if (errno != ERANGE) + break; + } + + return NULL; +} + +/* + * Initialize PWD in a new shell. + * If the shell is interactive, we need to warn if this fails. + */ +void +pwd_init(int warn) +{ + char *pwd; + struct stat stdot, stpwd; + + pwd = lookupvar("PWD"); + if (pwd && *pwd == '/' && stat(".", &stdot) != -1 && + stat(pwd, &stpwd) != -1 && + stdot.st_dev == stpwd.st_dev && + stdot.st_ino == stpwd.st_ino) { + if (curdir) + ckfree(curdir); + curdir = savestr(pwd); + } + if (getpwd() == NULL && warn) + out2fmt_flush("sh: cannot determine working directory\n"); + setvar("PWD", curdir, VEXPORT); +} |