qemu_multiarch_testing/*: make it easier to do debug in sandboxes

Signed-off-by: Denys Vlasenko <[email protected]>

Author: dvlasenk

qemu_multiarch_testing/README

@@ -39,3 +39,11 @@ And these did not:
 system-image-m68k    - qemu-system-m68k: -M q800: Unsupported machine type
 system-image-mips64  - init dies before reaching /mnt/init
 system-image-sh4     - hdc does not mount (no support for 2 disks)
+
+
+To debug a build problem in one of sandboxes, change keep_hdb
+to "keep_hdb=true" in parallel-build-hdc-img.sh
+
+This preserves system-image-DIR1/hdb.img after the build,
+so you can go into system-image-DIR1 and run
+"HDB=hdb.img ./dev-environment.sh" to debug the problem.

qemu_multiarch_testing/parallel-build-hdc-img.sh

@@ -1,13 +1,14 @@
 #!/bin/sh
 
 export HDBMEGS=64
+keep_hdb=false
 
 build_in_dir()
 {
 	cd "$1" || exit 1
 	rm -f hdb.img
 	nice -n10 time ./native-build.sh ../hdc.img
-	rm -f hdb.img
+	$keep_hdb || rm -f hdb.img
 	echo >&3 "Finished: $1"
 }