wc: don't miscount /sys and similar file systems

Fix similar problems in head, od, split, tac, and tail.
Reported by George Shuklin in: http://bugs.gnu.org/18621
* NEWS: Document this.
* src/head.c (elseek): Move up.
(elide_tail_bytes_pipe, elide_tail_lines_pipe): New arg
CURRENT_POS.  All uses changed.
(elide_tail_bytes_file, elide_tail_lines_file):
New arg ST and remove arg SIZE.  All uses changed.
* src/head.c (elide_tail_bytes_file):
* src/od.c (skip): Avoid optimization for /sys files, where
st_size is bogus and st_size == st_blksize.
Don't report error at EOF when not optimizing.
* src/head.c, src/od.c, src/tail.c: Include "stat-size.h".
* src/split.c (input_file_size): New function.
(bytes_split, lines_chunk_split, bytes_chunk_extract): New arg
INITIAL_READ.  All uses changed. Use it to double-check st_size.
* src/tac.c (tac_seekable): New arg FILE_POS.  All uses changed.
(copy_to_temp): Return size of temp file.  All uses changed.
* src/tac.c (tac_seekable):
* src/tail.c (tail_bytes):
* src/wc.c (wc):
Don't trust st_size; double-check by reading.
* src/wc.c (wc): New arg CURRENT_POS.  All uses changed.
* tests/local.mk (all_tests): Add tests/misc/wc-proc.sh,
tests/misc/od-j.sh, tests/tail-2/tail-c.sh.
* tests/misc/head-c.sh:
* tests/misc/tac-2-nonseekable.sh:
* tests/split/b-chunk.sh:
Add tests for problems with /proc and /sys files.
* tests/misc/od-j.sh, tests/misc/wc-proc.sh, tests/tail-2/tail-c.sh:
New files.

7 files changed, 158 insertions, 16 deletions

diff --git a/tests/local.mk b/tests/local.mk
index 8498acbbe..e01f4d830 100644
--- a/tests/local.mk
+++ b/tests/local.mk
@@ -256,6 +256,7 @@ all_tests =					\
   tests/misc/wc-files0-from.pl			\
   tests/misc/wc-files0.sh			\
   tests/misc/wc-parallel.sh			\
+  tests/misc/wc-proc.sh				\
   tests/misc/cat-proc.sh			\
   tests/misc/cat-buf.sh				\
   tests/misc/cat-self.sh			\
@@ -295,6 +296,7 @@ all_tests =					\
   tests/misc/nproc-positive.sh			\
   tests/misc/numfmt.pl				\
   tests/misc/od-N.sh				\
+  tests/misc/od-j.sh				\
   tests/misc/od-multiple-t.sh			\
   tests/misc/od-x8.sh				\
   tests/misc/paste.pl				\
@@ -399,6 +401,7 @@ all_tests =					\
   tests/tail-2/wait.sh				\
   tests/tail-2/retry.sh				\
   tests/tail-2/symlink.sh				\
+  tests/tail-2/tail-c.sh			\
   tests/chmod/c-option.sh			\
   tests/chmod/equal-x.sh			\
   tests/chmod/equals.sh				\
diff --git a/tests/misc/head-c.sh b/tests/misc/head-c.sh
index d6433d0dd..807e96544 100755
--- a/tests/misc/head-c.sh
+++ b/tests/misc/head-c.sh
@@ -42,4 +42,16 @@ esac
 # based on the value passed to -c
 (ulimit -v 20000; head --bytes=-$SSIZE_MAX < /dev/null) || fail=1
 
+# Make sure it works on funny files in /proc and /sys.
+
+for file in /proc/cpuinfo /sys/kernel/profiling; do
+  if test -r $file; then
+    cp -f $file copy &&
+    head -c -1 copy > exp1 || framework_failure_
+
+    head -c -1 $file > out1 || fail=1
+    compare exp1 out1 || fail=1
+  fi
+done
+
 Exit $fail
diff --git a/tests/misc/od-j.sh b/tests/misc/od-j.sh
new file mode 100755
index 000000000..a40a99ff7
--- /dev/null
+++ b/tests/misc/od-j.sh
@@ -0,0 +1,39 @@
+#!/bin/sh
+# Verify that 'od -j N' skips N bytes of input.
+
+# Copyright 2014 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
+print_ver_ od
+
+for file in ${srcdir=.}/tests/init.sh /proc/version /sys/kernel/profiling; do
+  test -r $file || continue
+
+  cp -f $file copy &&
+  bytes=$(wc -c < copy) || framework_failure_
+
+  od -An $file > exp || fail=1
+  od -An -j $bytes $file $file > out || fail=1
+  compare out exp || fail=1
+
+  od -An -j 4096 copy copy > exp1 2> experr1; expstatus=$?
+  od -An -j 4096 $file $file > out1 2> err1; status=$?
+  test $status -eq $expstatus || fail=1
+  compare out1 exp1 || fail=1
+  compare err1 experr1 || fail=1
+done
+
+Exit $fail
diff --git a/tests/misc/tac-2-nonseekable.sh b/tests/misc/tac-2-nonseekable.sh
index c27694c17..a4a35ab9d 100755
--- a/tests/misc/tac-2-nonseekable.sh
+++ b/tests/misc/tac-2-nonseekable.sh
@@ -1,5 +1,5 @@
 #!/bin/sh
-# ensure that tac works with two or more non-seekable inputs
+# ensure that tac works with non-seekable or quasi-seekable inputs
 
 # Copyright (C) 2011-2014 Free Software Foundation, Inc.
 
@@ -24,4 +24,16 @@ echo x > exp || fail=1
 compare exp out || fail=1
 compare /dev/null err || fail=1
 
+# Make sure it works on funny files in /proc and /sys.
+
+for file in /proc/version /sys/kernel/profiling; do
+  if test -r $file; then
+    cp -f $file copy &&
+    tac copy > exp1 || framework_failure_
+
+    tac $file > out1 || fail=1
+    compare exp1 out1 || fail=1
+  fi
+done
+
 Exit $fail
diff --git a/tests/misc/wc-proc.sh b/tests/misc/wc-proc.sh
new file mode 100755
index 000000000..828160d4f
--- /dev/null
+++ b/tests/misc/wc-proc.sh
@@ -0,0 +1,32 @@
+#!/bin/sh
+# Test wc on /proc and /sys files.
+
+# Copyright 2014 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
+print_ver_ wc
+
+for file in /proc/version /sys/kernel/profiling; do
+  if test -r $file; then
+    cp -f $file copy &&
+    wc -c < copy > exp1 || framework_failure_
+
+    wc -c < $file > out1 || fail=1
+    compare exp1 out1 || fail=1
+  fi
+done
+
+Exit $fail
diff --git a/tests/split/b-chunk.sh b/tests/split/b-chunk.sh
index 86f95a057..fefa0900d 100755
--- a/tests/split/b-chunk.sh
+++ b/tests/split/b-chunk.sh
@@ -31,20 +31,29 @@ stat x?? 2>/dev/null && fail=1
 
 printf '1\n2\n3\n4\n5\n' > in || framework_failure_
 
-split -n 3 in > out || fail=1
-split -n 1/3 in > b1 || fail=1
-split -n 2/3 in > b2 || fail=1
-split -n 3/3 in > b3 || fail=1
-printf '1\n2' > exp-1
-printf '\n3\n' > exp-2
-printf '4\n5\n' > exp-3
-
-compare exp-1 xaa || fail=1
-compare exp-2 xab || fail=1
-compare exp-3 xac || fail=1
-compare exp-1 b1 || fail=1
-compare exp-2 b2 || fail=1
-compare exp-3 b3 || fail=1
-test -f xad && fail=1
+for file in in /proc/version /sys/kernel/profiling; do
+  split -n 3 $file > out || fail=1
+  split -n 1/3 $file > b1 || fail=1
+  split -n 2/3 $file > b2 || fail=1
+  split -n 3/3 $file > b3 || fail=1
+
+  case $file in
+    in)
+      printf '1\n2' > exp-1
+      printf '\n3\n' > exp-2
+      printf '4\n5\n' > exp-3
+
+      compare exp-1 xaa || fail=1
+      compare exp-2 xab || fail=1
+      compare exp-3 xac || fail=1
+      ;;
+  esac
+
+  compare xaa b1 || fail=1
+  compare xab b2 || fail=1
+  compare xac b3 || fail=1
+  cat xaa xab xac | compare - $file || fail=1
+  test -f xad && fail=1
+done
 
 Exit $fail
diff --git a/tests/tail-2/tail-c.sh b/tests/tail-2/tail-c.sh
new file mode 100755
index 000000000..cdbaa46a9
--- /dev/null
+++ b/tests/tail-2/tail-c.sh
@@ -0,0 +1,35 @@
+#!/bin/sh
+# exercise tail -c
+
+# Copyright 2014 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
+print_ver_ tail
+require_ulimit_v_
+
+# Make sure it works on funny files in /proc and /sys.
+
+for file in /proc/version /sys/kernel/profiling; do
+  if test -r $file; then
+    cp -f $file copy &&
+    tail -c -1 copy > exp1 || framework_failure_
+
+    tail -c -1 $file > out1 || fail=1
+    compare exp1 out1 || fail=1
+  fi
+done
+
+Exit $fail