tests: move scsi_debug framework into shared script

* tests/t-local.sh (-scsi_debug_cleanup_, wait_for_dev_to_appear_):
(print_sd_names_, scsi_debug_setup_): New functions, factored out of ...
* tests/t9010-big-sector.sh: ...this file.

1 files changed, 3 insertions, 65 deletions

diff --git a/tests/t9010-big-sector.sh b/tests/t9010-big-sector.sh
index 180b07b..473bbf3 100755
--- a/tests/t9010-big-sector.sh
+++ b/tests/t9010-big-sector.sh
@@ -27,72 +27,10 @@ fi
 require_root_
 
 scsi_dev=
-cleanup_() { scsi_debug_cleanup_; }
-
-scsi_debug_cleanup_() {
-  # Remove the module only if this script added it.
-  test -z "$scsi_dev" && return
-
-  # We have to insist.  Otherwise, a single rmmod usually fails to remove it,
-  # due either to "Resource temporarily unavailable" or to
-  # "Module scsi_debug is in use".
-  for i in 1 2 3; do rmmod scsi_debug && break; sleep .2 || sleep 1; done
-}
-
-# Helper function: wait 2s (via .1s increments) for FILE to appear.
-# Usage: wait_for_dev_to_appear_ /dev/sdg
-# Return 0 upon success, 1 upon failure.
-wait_for_dev_to_appear_()
+cleanup_()
 {
-  local file=$1
-  local i=0
-  local incr=1
-  while :; do
-    ls "$file" > /dev/null 2>&1 && return 0
-    sleep .1 2>/dev/null || { sleep 1; incr=10; }
-    i=$(expr $i + $incr); test $i = 20 && break
-  done
-  return 1
-}
-
-print_sd_names_() { (cd /sys/block && printf '%s\n' sd*); }
-
-# Create a device using the scsi_debug module with the options passed to
-# this function as arguments.  Upon success, print the name of the new device.
-scsi_debug_setup_()
-{
-  # It is not trivial to determine the name of the device we're creating.
-  # Record the names of all /sys/block/sd* devices *before* probing:
-  print_sd_names_ > before
-  modprobe scsi_debug "$@" || { rm -f before; return 1; }
-
-  # Wait up to 2s (via .1s increments) for the list of devices to change.
-  # Sleeping for a fraction of a second requires GNU sleep, so fall
-  # back on sleeping 2x1s if that fails.
-  # FIXME-portability: using "cmp - ..." probably requires GNU cmp.
-  local incr=1
-  local i=0
-  while print_sd_names_ | cmp -s - before; do
-    sleep .1 2>/dev/null || { sleep 1; incr=10; }
-    i=$(expr $i + $incr); test $i = 20 && break
-  done
-
-  # Record the names of all /sys/block/sd* devices *after* probe+wait.
-  print_sd_names_ > after
-
-  # Determine which device names (if any) are new.
-  # There could be more than one new device, and there have been a removal.
-  local new_dev=$(comm -13 before after)
-  rm -f before after
-  case $new_dev in
-    sd[a-z]) ;;
-    sd[a-z][a-z]) ;;
-    *) return 1 ;;
-  esac
-  local t=/dev/$new_dev
-  wait_for_dev_to_appear_ $t
-  echo $t
-  return 0
+  # Remove the module only if this script added it.
+  test -n "$scsi_dev" && scsi_debug_cleanup_
 }
 
 # check for scsi_debug module