Please note that diffs are not public domain; they are subject to the copyright notices on the relevant files. =================================================================== RCS file: /ftp/cvs/cvsroot/src/lib/libc/gen/getcwd.c,v retrieving revision 1.2 retrieving revision 1.35 diff -u -p -r1.2 -r1.35 --- src/lib/libc/gen/getcwd.c 1993/07/30 08:22:24 1.2 +++ src/lib/libc/gen/getcwd.c 2005/01/23 01:00:51 1.35 @@ -1,6 +1,11 @@ +/* $NetBSD: getcwd.c,v 1.35 2005/01/23 01:00:51 enami Exp $ */ + /* - * Copyright (c) 1989, 1991 The Regents of the University of California. - * All rights reserved. + * Copyright (c) 1989, 1991, 1993, 1995 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Jan-Simon Pendry. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions @@ -10,11 +15,7 @@ * 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. All advertising materials mentioning features or use of this software - * must display the following acknowledgement: - * This product includes software developed by the University of - * California, Berkeley and its contributors. - * 4. Neither the name of the University nor the names of its contributors + * 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. * @@ -31,199 +32,200 @@ * SUCH DAMAGE. */ +#include #if defined(LIBC_SCCS) && !defined(lint) -/*static char sccsid[] = "from: @(#)getcwd.c 5.11 (Berkeley) 2/24/91";*/ -static char rcsid[] = "$Id: getcwd.c,v 1.2 1993/07/30 08:22:24 mycroft Exp $"; +#if 0 +static char sccsid[] = "@(#)getcwd.c 8.5 (Berkeley) 2/7/95"; +#else +__RCSID("$NetBSD: getcwd.c,v 1.35 2005/01/23 01:00:51 enami Exp $"); +#endif #endif /* LIBC_SCCS and not lint */ +#include "namespace.h" #include #include -#include + +#include #include +#include +#include #include #include #include #include -#define ISDOT(dp) \ - (dp->d_name[0] == '.' && (dp->d_name[1] == '\0' || \ - dp->d_name[1] == '.' && dp->d_name[2] == '\0')) +#include "extern.h" + +#ifdef __weak_alias +__weak_alias(getcwd,_getcwd) +__weak_alias(realpath,_realpath) +#endif +/* + * char *realpath(const char *path, char resolved_path[MAXPATHLEN]); + * + * Find the real name of path, by removing all ".", ".." and symlink + * components. Returns (resolved) on success, or (NULL) on failure, + * in which case the path which caused trouble is left in (resolved). + */ char * -getcwd(pt, size) - char *pt; - size_t size; +realpath(path, resolved) + const char *path; + char *resolved; { - register struct dirent *dp; - register DIR *dir; - register dev_t dev; - register ino_t ino; - register int first; - register char *bpt, *bup; - struct stat s; - dev_t root_dev; - ino_t root_ino; - size_t ptsize, upsize; - int save_errno; - char *ept, *eup, *up; + struct stat sb; + int fd, n, rootd, serrno, nlnk = 0; + char *p, *q, wbuf[MAXPATHLEN]; + + _DIAGASSERT(path != NULL); + _DIAGASSERT(resolved != NULL); + + /* Save the starting point. */ + if ((fd = open(".", O_RDONLY)) < 0) { + (void)strlcpy(resolved, ".", MAXPATHLEN); + return (NULL); + } /* - * If no buffer specified by the user, allocate one as necessary. - * If a buffer is specified, the size has to be non-zero. The path - * is built from the end of the buffer backwards. + * Find the dirname and basename from the path to be resolved. + * Change directory to the dirname component. + * lstat the basename part. + * if it is a symlink, read in the value and loop. + * if it is a directory, then change to that directory. + * get the current directory name and append the basename. */ - if (pt) { - ptsize = 0; - if (!size) { - errno = EINVAL; - return((char *)NULL); + if (strlcpy(resolved, path, MAXPATHLEN) >= MAXPATHLEN) { + errno = ENAMETOOLONG; + goto err1; + } +loop: + q = strrchr(resolved, '/'); + if (q != NULL) { + p = q + 1; + if (q == resolved) + q = "/"; + else { + do { + --q; + } while (q > resolved && *q == '/'); + q[1] = '\0'; + q = resolved; } - ept = pt + size; - } else { - if (!(pt = (char *)malloc(ptsize = 1024 - 4))) - return((char *)NULL); - ept = pt + ptsize; - } - bpt = ept - 1; - *bpt = '\0'; - - /* - * Allocate bytes (1024 - malloc space) for the string of "../"'s. - * Should always be enough (it's 340 levels). If it's not, allocate - * as necessary. Special * case the first stat, it's ".", not "..". - */ - if (!(up = (char *)malloc(upsize = 1024 - 4))) - goto err; - eup = up + MAXPATHLEN; - bup = up; - up[0] = '.'; - up[1] = '\0'; - - /* Save root values, so know when to stop. */ - if (stat("/", &s)) - goto err; - root_dev = s.st_dev; - root_ino = s.st_ino; - - errno = 0; /* XXX readdir has no error return. */ - - for (first = 1;; first = 0) { - /* Stat the current level. */ - if (lstat(up, &s)) - goto err; - - /* Save current node values. */ - ino = s.st_ino; - dev = s.st_dev; - - /* Check for reaching root. */ - if (root_dev == dev && root_ino == ino) { - *--bpt = '/'; - /* - * It's unclear that it's a requirement to copy the - * path to the beginning of the buffer, but it's always - * been that way and stuff would probably break. - */ - (void)bcopy(bpt, pt, ept - bpt); - free(up); - return(pt); - } - - /* - * Build pointer to the parent directory, allocating memory - * as necessary. Max length is 3 for "../", the largest - * possible component name, plus a trailing NULL. - */ - if (bup + 3 + MAXNAMLEN + 1 >= eup) { - if (!(up = (char *)realloc(up, upsize *= 2))) - goto err; - eup = up + upsize; - } - *bup++ = '.'; - *bup++ = '.'; - *bup = '\0'; - - /* Open and stat parent directory. */ - if (!(dir = opendir(up)) || fstat(dirfd(dir), &s)) - goto err; - - /* Add trailing slash for next directory. */ - *bup++ = '/'; - - /* - * If it's a mount point, have to stat each element because - * the inode number in the directory is for the entry in the - * parent directory, not the inode number of the mounted file. - */ - save_errno = 0; - if (s.st_dev == dev) { - for (;;) { - if (!(dp = readdir(dir))) - goto notfound; - if (dp->d_fileno == ino) - break; - } - } else - for (;;) { - if (!(dp = readdir(dir))) - goto notfound; - if (ISDOT(dp)) - continue; - bcopy(dp->d_name, bup, dp->d_namlen + 1); - - /* Save the first error for later. */ - if (lstat(up, &s)) { - if (!save_errno) - save_errno = errno; - errno = 0; - continue; - } - if (s.st_dev == dev && s.st_ino == ino) - break; + if (chdir(q) < 0) + goto err1; + } else + p = resolved; + + /* Deal with the last component. */ + if (lstat(p, &sb) == 0) { + if (S_ISLNK(sb.st_mode)) { + if (nlnk++ >= MAXSYMLINKS) { + errno = ELOOP; + goto err1; } + n = readlink(p, resolved, MAXPATHLEN-1); + if (n < 0) + goto err1; + resolved[n] = '\0'; + goto loop; + } + if (S_ISDIR(sb.st_mode)) { + if (chdir(p) < 0) + goto err1; + p = ""; + } + } + + /* + * Save the last component name and get the full pathname of + * the current directory. + */ + if (strlcpy(wbuf, p, sizeof(wbuf)) >= sizeof(wbuf)) { + errno = ENAMETOOLONG; + goto err1; + } + + /* + * Call the inernal internal version of getcwd which + * does a physical search rather than using the $PWD short-cut + */ + if (getcwd(resolved, MAXPATHLEN) == 0) + goto err1; - /* - * Check for length of the current name, preceding slash, - * leading slash. - */ - if (bpt - pt <= dp->d_namlen + (first ? 1 : 2)) { - size_t len, off; - - if (!ptsize) { - errno = ERANGE; - goto err; + /* + * Join the two strings together, ensuring that the right thing + * happens if the last component is empty, or the dirname is root. + */ + if (resolved[0] == '/' && resolved[1] == '\0') + rootd = 1; + else + rootd = 0; + + if (*wbuf) { + if (strlen(resolved) + strlen(wbuf) + (rootd ? 0 : 1) + 1 > + MAXPATHLEN) { + errno = ENAMETOOLONG; + goto err1; + } + if (rootd == 0) + if (strlcat(resolved, "/", MAXPATHLEN) >= MAXPATHLEN) { + errno = ENAMETOOLONG; + goto err1; } - off = bpt - pt; - len = ept - bpt; - if (!(pt = (char *)realloc(pt, ptsize *= 2))) - goto err; - bpt = pt + off; - ept = pt + ptsize; - (void)bcopy(bpt, ept - len, len); - bpt = ept - len; - } - if (!first) - *--bpt = '/'; - bpt -= dp->d_namlen; - bcopy(dp->d_name, bpt, dp->d_namlen); - (void)closedir(dir); - - /* Truncate any file name. */ - *bup = '\0'; - } - -notfound: - /* - * If readdir set errno, use it, not any saved error; otherwise, - * didn't find the current directory in its parent directory, set - * errno to ENOENT. - */ - if (!errno) - errno = save_errno ? save_errno : ENOENT; - /* FALLTHROUGH */ -err: - if (ptsize) - free(pt); - free(up); - return((char *)NULL); + if (strlcat(resolved, wbuf, MAXPATHLEN) >= MAXPATHLEN) { + errno = ENAMETOOLONG; + goto err1; + } + } + + /* Go back to where we came from. */ + if (fchdir(fd) < 0) { + serrno = errno; + goto err2; + } + + /* It's okay if the close fails, what's an fd more or less? */ + (void)close(fd); + return (resolved); + +err1: serrno = errno; + (void)fchdir(fd); +err2: (void)close(fd); + errno = serrno; + return (NULL); +} + +char * +getcwd(char *pt, size_t size) +{ + char *npt; + + /* + * If a buffer is specified, the size has to be non-zero. + */ + if (pt != NULL) { + if (size == 0) { + /* __getcwd(pt, 0) results ERANGE. */ + errno = EINVAL; + return (NULL); + } + if (__getcwd(pt, size) >= 0) + return (pt); + return (NULL); + } + + /* + * If no buffer specified by the user, allocate one as necessary. + */ + size = 1024 >> 1; + do { + if ((npt = realloc(pt, size <<= 1)) == NULL) + break; + pt = npt; + if (__getcwd(pt, size) >= 0) + return (pt); + } while (size <= MAXPATHLEN * 4 && errno == ERANGE); + + free(pt); + return (NULL); }