generic/003: ensure time changes between stat calls

On a fast device like a ramdisk, kernel time may not have changed
between a stat of a file and some operation on it immediately
afterwards. Hence there is no guarantee that an operation actually
changes the timestamps of a file immediately after it is stat'd.

Hence, ensure that the times will change by sleeping for a second
between the initial stat that reads the timestamps and the
operations that is supposed to modify them. This way we ensure that
the timestamp will change if the filesystem is correctly
implemented.

While there, fix the indenting to be 8 space tabs and correct the
header which is missing the bash shell declaration and the test
number identifier.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>

tests/generic/003

@@ -1,3 +1,6 @@
+#! /bin/bash
+# FS QA Test No. generic/003
+#
 # Tests the noatime, relatime, strictatime and nodiratime mount options.
 # There is an extra check for Btrfs to ensure that the access time is
 # never updated on read-only subvolumes. (Regression test for bug fixed
@@ -63,16 +66,15 @@ _compare_stat_times() {
 
 	for i in 0 1 2; do
 		if [ "${first_stat[$i]}" == "${second_stat[$i]}" ]; then
-            if [ "${updated:$i:1}" == "Y" ]; then
+			if [ "${updated:$i:1}" == "N" ]; then
+				continue;
+			fi
 			echo -n "ERROR: ${types[$i]} time has not been updated "
 			echo $test_step
-            fi
+		elif [ "${updated:$i:1}" == "N" ]; then
-        else
-            if [ "${updated:$i:1}" == "N" ]; then
 			echo -n "ERROR: ${types[$i]} time has changed "
 			echo $test_step
 		fi
-        fi
 	done
 }
 
@@ -91,12 +93,14 @@ echo "aaa" > $TPATH/dir1/file1
 file1_stat_before_first_access=`_stat $TPATH/dir1/file1`
 
 # Accessing file1 the first time
+sleep 1
 cat $TPATH/dir1/file1 > /dev/null
 file1_stat_after_first_access=`_stat $TPATH/dir1/file1`
 _compare_stat_times YNN "$file1_stat_before_first_access" \
 	"$file1_stat_after_first_access" "after accessing file1 first time"
 
 # Accessing file1 a second time
+sleep 1
 cat $TPATH/dir1/file1 > /dev/null
 file1_stat_after_second_access=`_stat $TPATH/dir1/file1`
 _compare_stat_times NNN "$file1_stat_after_first_access" \
@@ -112,6 +116,7 @@ _compare_stat_times NNN "$file1_stat_after_second_access" \
 # Creating dir2 and file2, checking directory stats
 mkdir $TPATH/dir2
 dir2_stat_before_file_creation=`_stat $TPATH/dir2`
+sleep 1
 echo "bbb" > $TPATH/dir2/file2
 dir2_stat_after_file_creation=`_stat $TPATH/dir2`
 _compare_stat_times NYY "$dir2_stat_before_file_creation" \
@@ -119,6 +124,7 @@ _compare_stat_times NYY "$dir2_stat_before_file_creation" \
 
 # Accessing file2
 file2_stat_before_first_access=`_stat $TPATH/dir2/file2`
+sleep 1
 cat $TPATH/dir2/file2 > /dev/null
 file2_stat_after_first_access=`_stat $TPATH/dir2/file2`
 _compare_stat_times YNN "$file2_stat_before_first_access" \
@@ -132,6 +138,7 @@ _scratch_unmount
 _scratch_mount "-o noatime"
 echo "ccc" > $TPATH/dir2/file3
 file3_stat_before_first_access=`_stat $TPATH/dir2/file3`
+sleep 1
 cat $TPATH/dir2/file3 > /dev/null
 file3_stat_after_first_access=`_stat $TPATH/dir2/file3`
 _compare_stat_times NNN "$file3_stat_before_first_access" \
@@ -139,10 +146,12 @@ _compare_stat_times NNN "$file3_stat_before_first_access" \
 
 # Checking that the modify and change times are still updated
 file1_stat_before_modify=`_stat $TPATH/dir1/file1`
+sleep 1
 echo "xyz" > $TPATH/dir1/file1
 file1_stat_after_modify=`_stat $TPATH/dir1/file1`
 _compare_stat_times NYY "$file1_stat_before_modify" \
 	"$file1_stat_after_modify" "after modifying file1"
+sleep 1
 mv $TPATH/dir1/file1 $TPATH/dir1/file1_renamed
 file1_stat_after_change=`_stat $TPATH/dir1/file1_renamed`
 _compare_stat_times NNY "$file1_stat_after_modify" \
@@ -156,6 +165,7 @@ cat $TPATH/dir2/file3 > /dev/null
 file3_stat_after_second_access=`_stat $TPATH/dir2/file3`
 _compare_stat_times YNN "$file3_stat_after_first_access" \
 	"$file3_stat_after_second_access" "after accessing file3 second time"
+sleep 1
 cat $TPATH/dir2/file3 > /dev/null
 file3_stat_after_third_access=`_stat $TPATH/dir2/file3`
 _compare_stat_times YNN "$file3_stat_after_second_access" \
@@ -167,6 +177,7 @@ if [ "$FSTYP" = "btrfs" ]; then
 	SPATH=$SCRATCH_MNT/snap1
 	btrfs subvol snapshot -r $TPATH $SPATH >> $seqres.full
 	dir2_stat_readonly_before_access=`_stat $SPATH/dir2`
+	sleep 1
 	ls $SPATH/dir2 >> $seqres.full
 	cat $SPATH/dir2/file3 >> $seqres.full
 	dir2_stat_readonly_after_access=`_stat $SPATH/dir2`
@@ -179,6 +190,7 @@ fi
 
 # Remounting read-only. Access time should never be updated, despite the
 # strictatime mount option.
+sleep 1
 dir2_stat_before_ro_mount=`_stat $TPATH/dir2`
 file3_stat_before_ro_mount=`_stat $TPATH/dir2/file3`
 _scratch_unmount