X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fstat.c;h=284da0cbc8a1cfe60dc3df5d09970e9757c9db12;hb=e57b0bd6cce7d468a30356c0a2cdab8a0af58eca;hp=00b956adbef87a627b7cfbbd795e22a3aaae8272;hpb=a0eead4f70b2bd4fd13efd99b4f7b27f5ca283cb;p=gnulib.git diff --git a/lib/stat.c b/lib/stat.c index 00b956adb..284da0cbc 100644 --- a/lib/stat.c +++ b/lib/stat.c @@ -1,7 +1,10 @@ -/* Work around the bug in some systems whereby stat succeeds when - given the zero-length file name argument. The stat from SunOS4.1.4 - has this bug. - Copyright (C) 1997 Free Software Foundation, Inc. +/* Work around the bug in some systems whereby stat/lstat succeeds when + given the zero-length file name argument. The stat/lstat from SunOS 4.1.4 + has this bug. Also work around a deficiency in Solaris systems (up to at + least Solaris 9) regarding the semantics of `lstat ("symlink/", sbuf).' + + Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003 Free + Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -21,30 +24,112 @@ #include -/* Disable the definition of stat to rpl_stat (from config.h) in this - file. Otherwise, we'd get conflicting prototypes for rpl_stat on - most systems. */ -#undef stat - #include #include #include #ifndef errno extern int errno; #endif +#if defined LSTAT && ! LSTAT_FOLLOWS_SLASHED_SYMLINK +# include + +# if HAVE_STDLIB_H +# include +# endif + +# ifdef STAT_MACROS_BROKEN +# undef S_ISLNK +# endif + +# ifndef S_ISLNK +# ifdef S_IFLNK +# define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK) +# else +# define S_ISLNK(m) 0 +# endif +# endif + +# ifndef HAVE_DECL_FREE +"this configure-time declaration test was not run" +# endif +# if !HAVE_DECL_FREE +void free (); +# endif + +# 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. + + If FILE has a trailing slash and specifies a symbolic link, + then append a `.' to FILE and call lstat a second time. */ + +static int +slash_aware_lstat (const char *file, struct stat *sbuf) +{ + size_t len; + char *new_file; + + int lstat_result = lstat (file, sbuf); -/* FIXME: describe. */ + if (lstat_result != 0 || !S_ISLNK (sbuf->st_mode)) + return lstat_result; + + len = strlen (file); + if (file[len - 1] != '/') + return lstat_result; + + /* FILE refers to a symbolic link and the name ends with a slash. + Append a `.' to FILE and repeat the lstat call. */ + + /* 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; + + lstat_result = lstat (new_file, sbuf); + free (new_file); + + return lstat_result; +} +#endif /* LSTAT && ! LSTAT_FOLLOWS_SLASHED_SYMLINK */ + +/* This is a wrapper for stat/lstat. + If FILE is the empty string, fail with errno == ENOENT. + Otherwise, return the result of calling the real stat/lstat. + + This works around the bug in some systems whereby stat/lstat succeeds when + given the zero-length file name argument. The stat/lstat from SunOS 4.1.4 + has this bug. */ + +/* This function also provides a version of lstat with consistent semantics + when FILE specifies a symbolic link and has a trailing slash. */ + +#ifdef LSTAT +# define rpl_xstat rpl_lstat +# if ! LSTAT_FOLLOWS_SLASHED_SYMLINK +# define xstat_return_val(F, S) slash_aware_lstat (F, S) +# else +# define xstat_return_val(F, S) lstat (F, S) +# endif +#else +# define rpl_xstat rpl_stat +# define xstat_return_val(F, S) stat (F, S) +#endif int -rpl_stat (file, sbuf) - const char *file; - struct stat *sbuf; +rpl_xstat (const char *file, struct stat *sbuf) { if (file && *file == 0) { - errno = EINVAL; + errno = ENOENT; return -1; } - return stat (file, sbuf); + return xstat_return_val (file, sbuf); }