From b88d20f97801465da4d0a24a6c3689b119b94eef Mon Sep 17 00:00:00 2001 From: Jim Meyering Date: Thu, 2 Feb 2006 21:25:06 +0000 Subject: Eliminate the unwelcome (albeit unlikely) possibility of xmalloc failure on deficient systems, and simplify gnulib lgpl dependencies. (rpl_lstat): Rewrite to use stat() in place of the xmalloc/lstat combination. Based on a patch from Bruno Haible. --- lib/lstat.c | 45 ++++++++++++++++++++++++--------------------- 1 file changed, 24 insertions(+), 21 deletions(-) diff --git a/lib/lstat.c b/lib/lstat.c index f5a22b07b..9b9c33e41 100644 --- a/lib/lstat.c +++ b/lib/lstat.c @@ -1,6 +1,6 @@ /* Work around a bug of lstat on some systems - Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free + Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify @@ -30,28 +30,28 @@ #include #include -#include #include +#include #include "stat-macros.h" -#include "xalloc.h" /* lstat works differently on Linux and Solaris systems. POSIX (see - `pathname resolution' in the glossary) requires that programs like `ls' - take into consideration the fact that FILE has a trailing slash when - FILE is a symbolic link. On Linux systems, the lstat function already - has the desired semantics (in treating `lstat("symlink/",sbuf)' just like - `lstat("symlink/.",sbuf)', but on Solaris it does not. + `pathname resolution' in the glossary) requires that programs like + `ls' take into consideration the fact that FILE has a trailing slash + when FILE is a symbolic link. On Linux and Solaris 10 systems, the + lstat function already has the desired semantics (in treating + `lstat ("symlink/", sbuf)' just like `lstat ("symlink/.", sbuf)', + but on Solaris 9 and earlier it does not. If FILE has a trailing slash and specifies a symbolic link, - then append a `.' to FILE and call lstat a second time. */ + then use stat() to get more info on the referent of FILE. + If the referent is a non-directory, then set errno to ENOTDIR + and return -1. Otherwise, return stat's result. */ int rpl_lstat (const char *file, struct stat *sbuf) { size_t len; - char *new_file; - int lstat_result = lstat (file, sbuf); if (lstat_result != 0 || !S_ISLNK (sbuf->st_mode)) @@ -59,19 +59,22 @@ rpl_lstat (const char *file, struct stat *sbuf) len = strlen (file); if (len == 0 || file[len - 1] != '/') - return lstat_result; + return 0; /* FILE refers to a symbolic link and the name ends with a slash. - Append a `.' to FILE and repeat the lstat call. */ + Call stat() to get info about the link's referent. */ - /* Add one for the `.' we'll append, and one more for the trailing NUL. */ - new_file = xmalloc (len + 1 + 1); - memcpy (new_file, file, len); - new_file[len] = '.'; - new_file[len + 1] = 0; + /* If stat fails, then we do the same. */ + if (stat (file, sbuf) != 0) + return -1; - lstat_result = lstat (new_file, sbuf); - free (new_file); + /* If FILE references a directory, return 0. */ + if (S_ISDIR (sbuf->st_mode)) + return 0; - return lstat_result; + /* Here, we know stat succeeded and FILE references a non-directory. + But it was specified via a name including a trailing slash. + Fail with errno set to ENOTDIR to indicate the contradiction. */ + errno = ENOTDIR; + return -1; } -- cgit v1.2.3-70-g09d2