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 1.34 retrieving revision 1.36.2.3 diff -u -p -r1.34 -r1.36.2.3 --- src/lib/libc/gen/getcwd.c 2005/01/06 23:43:32 1.34 +++ src/lib/libc/gen/getcwd.c 2006/01/01 23:12:36 1.36.2.3 @@ -1,4 +1,4 @@ -/* $NetBSD: getcwd.c,v 1.34 2005/01/06 23:43:32 simonb Exp $ */ +/* $NetBSD: getcwd.c,v 1.36.2.3 2006/01/01 23:12:36 riz Exp $ */ /* * Copyright (c) 1989, 1991, 1993, 1995 @@ -37,7 +37,7 @@ #if 0 static char sccsid[] = "@(#)getcwd.c 8.5 (Berkeley) 2/7/95"; #else -__RCSID("$NetBSD: getcwd.c,v 1.34 2005/01/06 23:43:32 simonb Exp $"); +__RCSID("$NetBSD: getcwd.c,v 1.36.2.3 2006/01/01 23:12:36 riz Exp $"); #endif #endif /* LIBC_SCCS and not lint */ @@ -46,10 +46,7 @@ __RCSID("$NetBSD: getcwd.c,v 1.34 2005/0 #include #include -#include #include -#include -#include #include #include #include @@ -61,188 +58,178 @@ __weak_alias(getcwd,_getcwd) __weak_alias(realpath,_realpath) #endif -#define ISDOT(dp) \ - (dp->d_name[0] == '.' && (dp->d_name[1] == '\0' || \ - (dp->d_name[1] == '.' && dp->d_name[2] == '\0'))) - - -#if defined(__SVR4) || defined(__svr4__) -#define d_fileno d_ino -#endif - /* - * char *realpath(const char *path, char resolved_path[MAXPATHLEN]); + * char *realpath(const char *path, char resolved[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 * -realpath(path, resolved) - const char *path; - char *resolved; +realpath(const char *path, char *resolved) { struct stat sb; - int fd, n, rootd, serrno, nlnk = 0; - char *p, *q, wbuf[MAXPATHLEN]; + int idx = 0, n, nlnk = 0; + const char *q; + char *p, wbuf[2][MAXPATHLEN]; + size_t len; _DIAGASSERT(path != NULL); _DIAGASSERT(resolved != NULL); - /* Save the starting point. */ - if ((fd = open(".", O_RDONLY)) < 0) { - (void)strlcpy(resolved, ".", MAXPATHLEN); - return (NULL); - } + /* + * Build real path one by one with paying an attention to ., + * .. and symbolic link. + */ /* - * 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. + * `p' is where we'll put a new component with prepending + * a delimiter. */ - if (strlcpy(resolved, path, MAXPATHLEN) >= MAXPATHLEN) { - errno = ENAMETOOLONG; - goto err1; + p = resolved; + + if (*path == 0) { + *p = 0; + errno = ENOENT; + return (NULL); } + + /* If relative path, start from current working directory. */ + if (*path != '/') { + if (getcwd(resolved, MAXPATHLEN) == NULL) { + p[0] = '.'; + p[1] = 0; + return (NULL); + } + len = strlen(resolved); + if (len > 1) + p += len; + } + 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; - } - 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'; + /* Skip any slash. */ + while (*path == '/') + path++; + + if (*path == 0) { + if (p == resolved) + *p++ = '/'; + *p = 0; + return (resolved); + } + + /* Find the end of this component. */ + q = path; + do + q++; + while (*q != '/' && *q != 0); + + /* Test . or .. */ + if (path[0] == '.') { + if (q - path == 1) { + path = q; goto loop; } - if (S_ISDIR(sb.st_mode)) { - if (chdir(p) < 0) - goto err1; - p = ""; + if (path[1] == '.' && q - path == 2) { + /* Trim the last component. */ + if (p != resolved) + while (*--p != '/') + ; + path = q; + goto loop; } } - /* - * Save the last component name and get the full pathname of - * the current directory. - */ - if (strlcpy(wbuf, p, sizeof(wbuf)) >= sizeof(wbuf)) { + /* Append this component. */ + if (p - resolved + 1 + q - path + 1 > MAXPATHLEN) { errno = ENAMETOOLONG; - goto err1; + if (p == resolved) + *p++ = '/'; + *p = 0; + return (NULL); } + p[0] = '/'; + memcpy(&p[1], path, + /* LINTED We know q > path. */ + q - path); + p[1 + q - path] = 0; /* - * 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; - - /* - * Join the two strings together, ensuring that the right thing - * happens if the last component is empty, or the dirname is root. + * If this component is a symlink, toss it and prepend link + * target to unresolved path. */ - 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 (lstat(resolved, &sb) == -1) { + return (NULL); + } + if (S_ISLNK(sb.st_mode)) { + if (nlnk++ >= MAXSYMLINKS) { + errno = ELOOP; + return (NULL); + } + n = readlink(resolved, wbuf[idx], sizeof(wbuf[0]) - 1); + if (n < 0) + return (NULL); + if (n == 0) { + errno = ENOENT; + return (NULL); } - if (rootd == 0) - if (strlcat(resolved, "/", MAXPATHLEN) >= MAXPATHLEN) { - errno = ENAMETOOLONG; - goto err1; - } - if (strlcat(resolved, wbuf, MAXPATHLEN) >= MAXPATHLEN) { + + /* Append unresolved path to link target and switch to it. */ + if (n + (len = strlen(q)) + 1 > sizeof(wbuf[0])) { errno = ENAMETOOLONG; - goto err1; + return (NULL); } + memcpy(&wbuf[idx][n], q, len + 1); + path = wbuf[idx]; + idx ^= 1; + + /* If absolute symlink, start from root. */ + if (*path == '/') + p = resolved; + goto loop; } - - /* Go back to where we came from. */ - if (fchdir(fd) < 0) { - serrno = errno; - goto err2; + if (*q == '/' && !S_ISDIR(sb.st_mode)) { + errno = ENOTDIR; + return (NULL); } - /* 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); + /* Advance both resolved and unresolved path. */ + p += 1 + q - path; + path = q; + goto loop; } char * -getcwd(pt, size) - char *pt; - size_t size; +getcwd(char *pt, size_t size) { - size_t ptsize, bufsize; - int len; - + char *npt; + /* - * 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 a buffer is specified, the size has to be non-zero. */ - if (pt) { - ptsize = 0; - if (!size) { + if (pt != NULL) { + if (size == 0) { + /* __getcwd(pt, 0) results ERANGE. */ errno = EINVAL; return (NULL); } - bufsize = size; - } else { - if ((pt = malloc(ptsize = 1024 - 4)) == NULL) - return (NULL); - bufsize = ptsize; - } - for (;;) { - len = __getcwd(pt, bufsize); - if ((len < 0) && (size == 0) && (errno == ERANGE)) { - if (ptsize > (MAXPATHLEN*4)) - return NULL; - if ((pt = realloc(pt, ptsize *= 2)) == NULL) - return NULL; - bufsize = ptsize; - continue; - } - break; - } - if (len < 0) - return NULL; - else - return pt; + 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); }