sh: Improve error handling in read builtin:

* If read -t times out, return status as if interrupted by SIGALRM
  (formerly 1).
* If a trapped signal interrupts read, return status 128+sig (formerly 1).
* If [EINTR] occurs but there is no trap, retry the read (for example
  because of a SIGWINCH in interactive mode).
* If a read error occurs, write an error message and return status 2.

As before, a variable assignment error returns 2 and discards the remaining
data read.

2 files changed, 18 insertions, 0 deletions

diff --git a/tools/regression/bin/sh/builtins/read7.0 b/tools/regression/bin/sh/builtins/read7.0
new file mode 100644
index 0000000..e78f887
--- /dev/null
+++ b/tools/regression/bin/sh/builtins/read7.0
@@ -0,0 +1,5 @@
+# $FreeBSD$
+
+{ errmsg=`read x <&- 2>&1 >&3`; } 3>&1
+r=$?
+[ "$r" -ge 2 ] && [ "$r" -le 128 ] && [ -n "$errmsg" ]
diff --git a/tools/regression/bin/sh/builtins/read8.0 b/tools/regression/bin/sh/builtins/read8.0
new file mode 100644
index 0000000..40dd6fa
--- /dev/null
+++ b/tools/regression/bin/sh/builtins/read8.0
@@ -0,0 +1,13 @@
+# $FreeBSD$
+
+T=`mktemp -d ${TMPDIR:-/tmp}/sh-test.XXXXXX`
+trap 'rm -rf $T' 0
+cd $T || exit 3
+mkfifo fifo1
+trapped=
+trap trapped=1 QUIT
+{ kill -QUIT $$; sleep 1; exit 4; } >fifo1 &
+read dummy <fifo1
+r=$?
+kill $!
+[ "$r" -gt 128 ] && [ -n "$trapped" ]