diff --git a/lib/fsusage.c b/lib/fsusage.c index 099b0aa..539f1a9 100644 --- a/lib/fsusage.c +++ b/lib/fsusage.c @@ -84,6 +84,33 @@ otherwise, use PROPAGATE_ALL_ONES. */ #define PROPAGATE_TOP_BIT(x) ((x) | ~ (EXTRACT_TOP_BIT (x) - 1)) +#ifdef STAT_STATVFS +/* Return true if statvfs works. This is false for statvfs on systems + with GNU libc on Linux kernels before 2.6.36, which stats all + preceding entries in /proc/mounts; that makes df hang if even one + of the corresponding file systems is hard-mounted but not available. */ +# if ! (__linux__ && (__GLIBC__ || __UCLIBC__)) +static int statvfs_works (void) { return 1; } +# else +# include /* for strverscmp */ +# include +# include +# define STAT_STATFS2_BSIZE 1 + +static int +statvfs_works (void) +{ + static int statvfs_works_cache = -1; + struct utsname name; + if (statvfs_works_cache < 0) + statvfs_works_cache = (uname (&name) == 0 + && 0 <= strverscmp (name.release, "2.6.36")); + return statvfs_works_cache; +} +# endif +#endif + + /* Fill in the fields of FSP with information about space usage for the file system on which FILE resides. DISK is the device on which FILE is mounted, for space-getting @@ -94,19 +121,32 @@ int get_fs_usage (char const *file, char const *disk, struct fs_usage *fsp) { -#if defined STAT_STATVFS /* POSIX, except glibc/Linux */ +#ifdef STAT_STATVFS /* POSIX, except pre-2.6.36 glibc/Linux */ - struct statvfs fsd; - - if (statvfs (file, &fsd) < 0) - return -1; + if (statvfs_works ()) + { + struct statvfs vfsd; + + if (statvfs (file, &vfsd) < 0) + return -1; + + /* f_frsize isn't guaranteed to be supported. */ + fsp->fsu_blocksize = (vfsd.f_frsize + ? PROPAGATE_ALL_ONES (vfsd.f_frsize) + : PROPAGATE_ALL_ONES (vfsd.f_bsize)); + + fsp->fsu_blocks = PROPAGATE_ALL_ONES (vfsd.f_blocks); + fsp->fsu_bfree = PROPAGATE_ALL_ONES (vfsd.f_bfree); + fsp->fsu_bavail = PROPAGATE_TOP_BIT (vfsd.f_bavail); + fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (vfsd.f_bavail) != 0; + fsp->fsu_files = PROPAGATE_ALL_ONES (vfsd.f_files); + fsp->fsu_ffree = PROPAGATE_ALL_ONES (vfsd.f_ffree); + return 0; + } - /* f_frsize isn't guaranteed to be supported. */ - fsp->fsu_blocksize = (fsd.f_frsize - ? PROPAGATE_ALL_ONES (fsd.f_frsize) - : PROPAGATE_ALL_ONES (fsd.f_bsize)); +#endif -#elif defined STAT_STATVFS64 /* AIX */ +#if defined STAT_STATVFS64 /* AIX */ struct statvfs64 fsd; @@ -235,7 +275,7 @@ get_fs_usage (char const *file, char const *disk, struct fs_usage *fsp) #endif -#if (defined STAT_STATVFS || defined STAT_STATVFS64 \ +#if (defined STAT_STATVFS64 \ || (!defined STAT_STATFS2_FS_DATA && !defined STAT_READ_FILSYS)) fsp->fsu_blocks = PROPAGATE_ALL_ONES (fsd.f_blocks); diff --git a/m4/fsusage.m4 b/m4/fsusage.m4 index 519743f..f87834e 100644 --- a/m4/fsusage.m4 +++ b/m4/fsusage.m4 @@ -50,14 +50,6 @@ if test $ac_fsusage_space = no; then # OpenBSD >= 4.4, AIX, HP-UX, IRIX, Solaris, Cygwin, Interix, BeOS. AC_CACHE_CHECK([for statvfs function (SVR4)], [fu_cv_sys_stat_statvfs], [AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include -#if (defined __GLIBC__ || defined __UCLIBC__) && defined __linux__ -Do not use statvfs on systems with GNU libc on Linux, because that function -stats all preceding entries in /proc/mounts, and that makes df hang if even -one of the corresponding file systems is hard-mounted, but not available. -statvfs in GNU libc on Hurd, BeOS, Haiku operates differently: it only makes -a system call. -#endif - #ifdef __osf__ "Do not use Tru64's statvfs implementation" #endif