Pádraig Brady wrote: ... >> +# Use a limit of N = SIZE_MAX - max_BUFSIZ >> +# The "- max_BUFSIZ" term is because head must be able to add BUFSIZ >> +# to the selected value of N without exceeding SIZE_MAX. >> +# Since we've seen BUFSIZ up to 128K, use 256K to be safe. >> +max_BUFSIZ=$(expr 256 '*' 1024) >> + >> +# It's ok to use a 10-digit $SIZE_MAX, because expr uses wider intmax_t. >> +# However, when $SIZE_MAX is longer, it's a 20-digit quantity that is >> +# too large for GMP-disabled expr to handle, so use $SSIZE_MAX there. >> +# We'd use $SSIZE_MAX in both cases, but want to keep the number as >> +# large as possible for the 32-bit case, since there, it may barely >> +# exceed the size of available RAM, while SSIZE_MAX probably will not. >> +test $(printf $SIZE_MAX|wc -c) -lt 11 \ >> + && big=$SIZE_MAX \ >> + || big=$SSIZE_MAX >> + >> +lim=$(expr $big - $max_BUFSIZ) \ > > trailing \ is not needed. > > The above assumes intmax_t is always wider than size_t, > which is might be OK? > Also since OFF_T_MAX is checked earlier in the code, > it assumes that off_t is wider than size_t which isn't > the case if _FILE_OFFSET_BITS is not 64. > > You could take the approach to just use $SSIZE_MAX, > and assume 64 bit testing covers the 32 bit case implicitly? > That would also assume that off_t was never narrower than size_t, > but that's probably OK. > > These limits are painful. Sorry for the churn :(
This started because the test passed on 64-bit, yet failed on 32-bit. If it were to use $SSIZE_MAX, the test could mistakenly pass when run without the underlying patch, because on a 32-bit system, it's not uncommon to have 2^31 bytes of RAM, so the allocation could succeed. However, that's so much simpler that I now think it's the way to go. Thanks! >From aeaeb87c134ce748527ba99e749b7369fcba2438 Mon Sep 17 00:00:00 2001 From: Jim Meyering <meyer...@fb.com> Date: Mon, 27 May 2013 17:01:14 -0700 Subject: [PATCH] tests: head-c: avoid spurious failure with a 32-bit size_t * tests/misc/head-c.sh: Don't try to elide 1 exabytes, since on 32-bit systems, that number is not representable as a size_t. This command would fail on 32-bit systems, where SIZE_MAX < 1E: head --bytes=-E < /dev/null Instead of "E", use $SSIZE_MAX. For discussion, see http://bugs.gnu.org/13530 --- tests/misc/head-c.sh | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tests/misc/head-c.sh b/tests/misc/head-c.sh index 37a86ce..a5b6c6a 100755 --- a/tests/misc/head-c.sh +++ b/tests/misc/head-c.sh @@ -19,6 +19,7 @@ . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src print_ver_ head require_ulimit_v_ +getlimits_ # exercise the fix of 2001-08-18, based on test case from Ian Bruce echo abc > in || framework_failure_ @@ -31,6 +32,6 @@ esac # Only allocate memory as needed. # Coreutils <= 8.21 would allocate memory up front # based on the value passed to -c -(ulimit -v 20000; head --bytes=-E < /dev/null) || fail=1 +(ulimit -v 20000; head --bytes=-$SSIZE_MAX < /dev/null) || fail=1 Exit $fail -- 1.8.3.101.g727a46b
