/*- * See the file LICENSE for redistribution information. * * Copyright (c) 1996,2008 Oracle. All rights reserved. */ /* * Copyright (c) 1989, 1991, 1993 * The Regents of the University of California. All rights reserved. * * 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. * * $Id: getcwd.c,v 12.10 2008/01/08 20:58:07 bostic Exp $ */ #include "db_config.h" #include "db_int.h" #ifdef HAVE_SYSTEM_INCLUDE_FILES #if HAVE_DIRENT_H # include # define NAMLEN(dirent) strlen((dirent)->d_name) #else # define dirent direct # define NAMLEN(dirent) (dirent)->d_namlen # if HAVE_SYS_NDIR_H # include # endif # if HAVE_SYS_DIR_H # include # endif # if HAVE_NDIR_H # include # endif #endif #endif #define ISDOT(dp) \ (dp->d_name[0] == '.' && (dp->d_name[1] == '\0' || \ (dp->d_name[1] == '.' && dp->d_name[2] == '\0'))) #ifndef dirfd #define dirfd(dirp) ((dirp)->dd_fd) #endif /* * getcwd -- * Get the current working directory. * * PUBLIC: #ifndef HAVE_GETCWD * PUBLIC: char *getcwd __P((char *, size_t)); * PUBLIC: #endif */ char * getcwd(pt, size) char *pt; size_t size; { 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 ret, save_errno; char *ept, *eup, *up; /* * 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. */ if (pt) { ptsize = 0; if (!size) { __os_set_errno(EINVAL); return (NULL); } if (size == 1) { __os_set_errno(ERANGE); return (NULL); } ept = pt + size; } else { if ((ret = __os_malloc(NULL, ptsize = 1024 - 4, &pt)) != 0) { __os_set_errno(ret); return (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 ((ret = __os_malloc(NULL, upsize = 1024 - 4, &up)) != 0) goto err; eup = up + 1024; 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; __os_set_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 = PATH_SEPARATOR[0]; /* * 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. */ bcopy(bpt, pt, ept - bpt); __os_free(NULL, 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 (__os_realloc(NULL, upsize *= 2, &up) != 0) goto err; bup = up; 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++ = PATH_SEPARATOR[0]; /* * 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 == 0) save_errno = __os_get_errno(); __os_set_errno(0); continue; } if (s.st_dev == dev && s.st_ino == ino) break; } /* * 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) { __os_set_errno(ERANGE); goto err; } off = bpt - pt; len = ept - bpt; if (__os_realloc(NULL, ptsize *= 2, &pt) != 0) goto err; bpt = pt + off; ept = pt + ptsize; bcopy(bpt, ept - len, len); bpt = ept - len; } if (!first) *--bpt = PATH_SEPARATOR[0]; 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 (__os_get_errno_ret_zero() == 0) __os_set_errno(save_errno == 0 ? ENOENT : save_errno); /* FALLTHROUGH */ err: if (ptsize) __os_free(NULL, pt); __os_free(NULL, up); return (NULL); }