[kvm-unit-tests PATCH 4/5] scripts/arch-run: fix qemu binary search failure path

["Radim Krčmář" <rkrcmar@redhat.com>]

Doing exit from a subshell won't exit the main shell, so arch-run will
try to continue without a working QEMU if search_qemu_binary() failed.

Also fix error message from search_qemu_binary().

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
---
I was thinking about using `set -e` instead, so the "return 2" from
search_qemu_binary() would stop the script without the explicit exit.
It required just four changes to make the script work (resulting in
better diffstat), but would likely complicate future development.

The second alternative would be to call just "search_qemu_binary" and
set the qemu variable from it.  This would allow "exit 2" from
search_qemu_binary() to also exit arch/run, but side-effects on
variables seem worse than the first alternative ...
---
 arm/run               | 3 ++-
 powerpc/run           | 3 ++-
 s390x/run             | 3 ++-
 scripts/arch-run.bash | 6 +++---
 x86/run               | 3 ++-
 5 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/arm/run b/arm/run
index 8d8918a461dc..d7d778fe1645 100755
--- a/arm/run
+++ b/arm/run
@@ -31,7 +31,8 @@ if [ -z "$ACCEL" ]; then
 	fi
 fi
 
-qemu=$(search_qemu_binary)
+qemu=$(search_qemu_binary) ||
+	exit 2
 
 if ! $qemu -machine '?' 2>&1 | grep 'ARM Virtual Machine' > /dev/null; then
 	echo "$qemu doesn't support mach-virt ('-machine virt'). Exiting."
diff --git a/powerpc/run b/powerpc/run
index 3f69386c642a..e43c9fd8063c 100755
--- a/powerpc/run
+++ b/powerpc/run
@@ -28,7 +28,8 @@ if [ -z "$ACCEL" ]; then
 	fi
 fi
 
-qemu=$(search_qemu_binary)
+qemu=$(search_qemu_binary) ||
+	exit 2
 
 if ! $qemu -machine '?' 2>&1 | grep 'pseries' > /dev/null; then
 	echo "$qemu doesn't support pSeries ('-machine pseries'). Exiting."
diff --git a/s390x/run b/s390x/run
index 6df348a93783..ce8d45c2c8fd 100755
--- a/s390x/run
+++ b/s390x/run
@@ -28,7 +28,8 @@ if [ -z "$ACCEL" ]; then
 	fi
 fi
 
-qemu=$(search_qemu_binary)
+qemu=$(search_qemu_binary) ||
+	exit 2
 
 M='-machine s390-ccw-virtio'
 M+=",accel=$ACCEL"
diff --git a/scripts/arch-run.bash b/scripts/arch-run.bash
index 6e429a8748f4..994c1aa9c0cd 100644
--- a/scripts/arch-run.bash
+++ b/scripts/arch-run.bash
@@ -176,9 +176,9 @@ search_qemu_binary ()
 	done
 
 	if [ -z "$qemu" ]; then
-		echo "A QEMU binary was not found."
-		echo "You can set a custom location by using the QEMU=<path> environment variable."
-		exit 2
+		echo "A QEMU binary was not found." >&2
+		echo "You can set a custom location by using the QEMU=<path> environment variable." >&2
+		return 2
 	fi
 	command -v $qemu
 	export PATH=$save_path
diff --git a/x86/run b/x86/run
index a06a7c0f80c8..1099c5ccd609 100755
--- a/x86/run
+++ b/x86/run
@@ -9,7 +9,8 @@ if [ -z "$STANDALONE" ]; then
 	source scripts/arch-run.bash
 fi
 
-qemu=$(search_qemu_binary)
+qemu=$(search_qemu_binary) ||
+	exit 2
 
 if ! ${qemu} -device '?' 2>&1 | grep -F -e \"testdev\" -e \"pc-testdev\" > /dev/null;
 then
-- 
2.13.2