1 /* Work around a bug of lstat on some systems 2 3 Copyright (C) 1997-2006, 2008-2021 Free Software Foundation, Inc. 4 5 This file is free software: you can redistribute it and/or modify 6 it under the terms of the GNU Lesser General Public License as 7 published by the Free Software Foundation; either version 2.1 of the 8 License, or (at your option) any later version. 9 10 This file is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public License 16 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 17 18 /* written by Jim Meyering */ 19 20 /* If the user's config.h happens to include <sys/stat.h>, let it include only 21 the system's <sys/stat.h> here, so that orig_lstat doesn't recurse to 22 rpl_lstat. */ 23 #define __need_system_sys_stat_h 24 #include <config.h> 25 26 #if !HAVE_LSTAT 27 /* On systems that lack symlinks, our replacement <sys/stat.h> already 28 defined lstat as stat, so there is nothing further to do other than 29 avoid an empty file. */ 30 typedef int dummy; 31 #else /* HAVE_LSTAT */ 32 33 /* Get the original definition of lstat. It might be defined as a macro. */ 34 # include <sys/types.h> 35 # include <sys/stat.h> 36 # undef __need_system_sys_stat_h 37 38 static int 39 orig_lstat (const char *filename, struct stat *buf) /* */ 40 { 41 return lstat (filename, buf); 42 } 43 44 /* Specification. */ 45 # ifdef __osf__ 46 /* Write "sys/stat.h" here, not <sys/stat.h>, otherwise OSF/1 5.1 DTK cc 47 eliminates this include because of the preliminary #include <sys/stat.h> 48 above. */ 49 # include "sys/stat.h" 50 # else 51 # include <sys/stat.h> 52 # endif 53 54 # include "stat-time.h" 55 56 # include <string.h> 57 # include <errno.h> 58 59 /* lstat works differently on Linux and Solaris systems. POSIX (see 60 "pathname resolution" in the glossary) requires that programs like 61 'ls' take into consideration the fact that FILE has a trailing slash 62 when FILE is a symbolic link. On Linux and Solaris 10 systems, the 63 lstat function already has the desired semantics (in treating 64 'lstat ("symlink/", sbuf)' just like 'lstat ("symlink/.", sbuf)', 65 but on Solaris 9 and earlier it does not. 66 67 If FILE has a trailing slash and specifies a symbolic link, 68 then use stat() to get more info on the referent of FILE. 69 If the referent is a non-directory, then set errno to ENOTDIR 70 and return -1. Otherwise, return stat's result. */ 71 72 int 73 rpl_lstat (const char *file, struct stat *sbuf) /* */ 74 { 75 int result = orig_lstat (file, sbuf); 76 77 /* This replacement file can blindly check against '/' rather than 78 using the ISSLASH macro, because all platforms with '\\' either 79 lack symlinks (mingw) or have working lstat (cygwin) and thus do 80 not compile this file. 0 len should have already been filtered 81 out above, with a failure return of ENOENT. */ 82 if (result == 0) 83 { 84 if (S_ISDIR (sbuf->st_mode) || file[strlen (file) - 1] != '/') 85 result = stat_time_normalize (result, sbuf); 86 else 87 { 88 /* At this point, a trailing slash is permitted only on 89 symlink-to-dir; but it should have found information on the 90 directory, not the symlink. Call 'stat' to get info about the 91 link's referent. Our replacement stat guarantees valid results, 92 even if the symlink is not pointing to a directory. */ 93 if (!S_ISLNK (sbuf->st_mode)) 94 { 95 errno = ENOTDIR; 96 return -1; 97 } 98 result = stat (file, sbuf); 99 } 100 } 101 return result; 102 } 103 104 #endif /* HAVE_LSTAT */