fs_mgr: test: track device active slot throughout

Report any discrepancy in the active slot.

Fix a problem with problematic error propagation for adb_cat()

Test: adb-remount-test.sh
Bug: 126256072
Change-Id: I8a5d4e364945c5e60d252333886987b8dca0cfb3
diff --git a/fs_mgr/tests/adb-remount-test.sh b/fs_mgr/tests/adb-remount-test.sh
index a6baf1d..bd5a4fe 100755
--- a/fs_mgr/tests/adb-remount-test.sh
+++ b/fs_mgr/tests/adb-remount-test.sh
@@ -48,6 +48,7 @@
 TMPDIR=${TMPDIR:-/tmp}
 print_time=false
 start_time=`date +%s`
+ACTIVE_SLOT=
 
 ##
 ##  Helper Functions
@@ -77,6 +78,7 @@
       wc -l | grep '^1$' >/dev/null
     fi
 }
+
 [ "USAGE: inRecovery
 
 Returns: true if device is in recovery mode" ]
@@ -221,15 +223,23 @@
 
 Returns: waits until the device has returned for adb or optional timeout" ]
 adb_wait() {
+  local ret
   if [ -n "${1}" ]; then
     echo -n ". . . waiting `format_duration ${1}`" ${ANDROID_SERIAL} ${USB_ADDRESS} "${CR}"
     timeout --preserve-status --signal=KILL ${1} adb wait-for-device 2>/dev/null
-    local ret=${?}
+    ret=${?}
     echo -n "                                                                             ${CR}"
-    return ${ret}
   else
     adb wait-for-device
+    ret=${?}
   fi
+  if [ 0 = ${ret} -a -n "${ACTIVE_SLOT}" ]; then
+    local active_slot=`get_active_slot`
+    if [ X"${ACTIVE_SLOT}" != X"${active_slot}" ]; then
+      echo "${ORANGE}[  WARNING ]${NORMAL} Active slot changed from ${ACTIVE_SLOT} to ${active_slot}" >&2
+    fi
+  fi
+  return ${ret}
 }
 
 [ "USAGE: usb_status > stdout
@@ -254,33 +264,50 @@
 
 Returns: waits until the device has returned for fastboot or optional timeout" ]
 fastboot_wait() {
+  local ret
   # fastboot has no wait-for-device, but it does an automatic
   # wait and requires (even a nonsensical) command to do so.
   if [ -n "${1}" ]; then
     echo -n ". . . waiting `format_duration ${1}`" ${ANDROID_SERIAL} ${USB_ADDRESS} "${CR}"
     timeout --preserve-status --signal=KILL ${1} fastboot wait-for-device >/dev/null 2>/dev/null
-    local ret=${?}
+    ret=${?}
     echo -n "                                                                             ${CR}"
     ( exit ${ret} )
   else
     fastboot wait-for-device >/dev/null 2>/dev/null
   fi ||
     inFastboot
+  ret=${?}
+  if [ 0 = ${ret} -a -n "${ACTIVE_SLOT}" ]; then
+    local active_slot=`get_active_slot`
+    if [ X"${ACTIVE_SLOT}" != X"${active_slot}" ]; then
+      echo "${ORANGE}[  WARNING ]${NORMAL} Active slot changed from ${ACTIVE_SLOT} to ${active_slot}" >&2
+    fi
+  fi
+  return ${ret}
 }
 
 [ "USAGE: recovery_wait [timeout]
 
 Returns: waits until the device has returned for recovery or optional timeout" ]
 recovery_wait() {
+  local ret
   if [ -n "${1}" ]; then
     echo -n ". . . waiting `format_duration ${1}`" ${ANDROID_SERIAL} ${USB_ADDRESS} "${CR}"
     timeout --preserve-status --signal=KILL ${1} adb wait-for-recovery 2>/dev/null
-    local ret=${?}
+    ret=${?}
     echo -n "                                                                             ${CR}"
-    return ${ret}
   else
     adb wait-for-recovery
+    ret=${?}
   fi
+  if [ 0 = ${ret} -a -n "${ACTIVE_SLOT}" ]; then
+    local active_slot=`get_active_slot`
+    if [ X"${ACTIVE_SLOT}" != X"${active_slot}" ]; then
+      echo "${ORANGE}[  WARNING ]${NORMAL} Active slot changed from ${ACTIVE_SLOT} to ${active_slot}" >&2
+    fi
+  fi
+  return ${ret}
 }
 
 [ "any_wait [timeout]
@@ -326,7 +353,7 @@
     [ root != "`adb_sh echo '${USER}' </dev/null`" ]
 }
 
-[ "USAGE: fastboot_getvar var expected
+[ "USAGE: fastboot_getvar var expected >/dev/stderr
 
 Returns: true if var output matches expected" ]
 fastboot_getvar() {
@@ -350,6 +377,19 @@
   echo ${O} >&2
 }
 
+[ "USAGE: get_active_slot >/dev/stdout
+
+Returns: with a or b string reporting active slot" ]
+get_active_slot() {
+  if inAdb || inRecovery; then
+    get_property ro.boot.slot_suffix | tr -d _
+  elif inFastboot; then
+    fastboot_getvar current-slot 2>&1 | sed -n 's/current-slot: //p'
+  else
+    false
+  fi
+}
+
 [ "USAGE: restore
 
 Do nothing: should be redefined when necessary.  Called after cleanup.
@@ -583,6 +623,9 @@
 BUILD_DESCRIPTION=`get_property ro.build.description`
 [ -z "${BUILD_DESCRIPTION}" ] ||
   echo "${BLUE}[     INFO ]${NORMAL} ${BUILD_DESCRIPTION}" >&2
+ACTIVE_SLOT=`get_active_slot`
+[ -z "${ACTIVE_SLOT}" ] ||
+  echo "${BLUE}[     INFO ]${NORMAL} active slot is ${ACTIVE_SLOT}" >&2
 
 # Report existing partition sizes
 adb_sh ls -l /dev/block/by-name/ </dev/null 2>/dev/null |
@@ -1031,13 +1074,7 @@
   check_eq "${A}" "${B}" system after flash vendor
   adb_root ||
     die "adb root"
-  B="`adb_cat /vendor/hello`" &&
-    if ${is_userspace_fastboot} || ! ${overlayfs_needed}; then
-      die "re-read /vendor/hello after flash vendor"
-    else
-      echo "${ORANGE}[  WARNING ]${NORMAL} user fastboot missing required to invalidate, ignoring a failure" >&2
-      echo "${ORANGE}[  WARNING ]${NORMAL} re-read /vendor/hello after flash vendor" >&2
-    fi
+  B="`adb_cat /vendor/hello`"
   if ${is_userspace_fastboot} || ! ${overlayfs_needed}; then
     check_eq "cat: /vendor/hello: No such file or directory" "${B}" \
              vendor content after flash vendor