Add a version number to the wal-index header. If SQLite encounters a version number in either the wal or wal-index files that it does not understand, the operation is abandoned and SQLITE_CANTOPEN returned.

FossilOrigin-Name: 8d0f8a7f70d6fb42369411a934b30f8c8ca8322f

test/walcksum.test

@@ -13,35 +13,10 @@
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
 source $testdir/lock_common.tcl
+source $testdir/wal_common.tcl
 
 ifcapable !wal {finish_test ; return }
 
-# This proc calculates checksums in the same way as those used by SQLite 
-# in WAL files. If the $endian argument is "big", then checksums are
-# calculated by interpreting data as an array of big-endian integers. If
-# it is "little", data is interpreted as an array of little-endian integers.
-#
-proc log_cksum {endian ckv1 ckv2 blob} {
-  upvar $ckv1 c1
-  upvar $ckv2 c2
-
-  if {$endian!="big" && $endian!="little"} {
-    return -error "Bad value \"$endian\" - must be \"big\" or \"little\""
-  }
-  set scanpattern I*
-  if {$endian == "little"} { set scanpattern i* }
-
-  binary scan $blob $scanpattern values
-  foreach {v1 v2} $values {
-    set c1 [expr {($c1 + $v1 + $c2)&0xFFFFFFFF}]
-    set c2 [expr {($c2 + $v2 + $c1)&0xFFFFFFFF}]
-  }
-}
-
-proc log_file_size {nFrame pgsz} {
-  expr {24 + ($pgsz+24)*$nFrame}
-}
-
 # Read and return the contents of file $filename. Treat the content as
 # binary data.
 #
@@ -72,7 +47,6 @@ proc log_checksum_verify {filename iFrame endian} {
   expr {$c1==$expect1 && $c2==$expect2}
 }
 
-#
 # File $filename must be a WAL file on disk. Compute the checksum for frame
 # $iFrame in the file by interpreting data as $endian-endian integers 
 # ($endian must be either "big" or "little"). Then write the computed 
@@ -92,21 +66,38 @@ proc log_checksum_write {filename iFrame endian} {
   close $fd
 }
 
+# Calculate and return the checksum for a particular frame in a WAL.
+#
+# Arguments are:
+#
+#   $data         Blob containing the entire contents of a WAL.
+#
+#   $iFrame       Frame number within the $data WAL. Frames are numbered 
+#                 starting at 1.
+#
+#   $endian       One of "big" or "little".
+#
+# Returns a list of three elements, as follows:
+#
+#   * The byte offset of the checksum belonging to frame $iFrame in the WAL.
+#   * The first integer in the calculated version of the checksum.
+#   * The second integer in the calculated version of the checksum.
+#
 proc log_checksum_calc {data iFrame endian} {
   
   binary scan [string range $data 8 11] I pgsz
   if {$iFrame > 1} {
-    set n [log_file_size [expr $iFrame-2] $pgsz]
+    set n [wal_file_size [expr $iFrame-2] $pgsz]
     binary scan [string range $data [expr $n+16] [expr $n+23]] II c1 c2
   } else {
     set c1 0
     set c2 0
-    log_cksum $endian c1 c2 [string range $data 0 23]
+    wal_cksum $endian c1 c2 [string range $data 0 23]
   }
 
-  set n [log_file_size [expr $iFrame-1] $pgsz]
-  log_cksum $endian c1 c2 [string range $data $n [expr $n+7]]
-  log_cksum $endian c1 c2 [string range $data [expr $n+24] [expr $n+24+$pgsz-1]]
+  set n [wal_file_size [expr $iFrame-1] $pgsz]
+  wal_cksum $endian c1 c2 [string range $data $n [expr $n+7]]
+  wal_cksum $endian c1 c2 [string range $data [expr $n+24] [expr $n+24+$pgsz-1]]
 
   list [expr $n+16] $c1 $c2
 }
@@ -116,6 +107,9 @@ proc log_checksum_calc {data iFrame endian} {
 # WAL header to indicate that checksums are $endian-endian ($endian must be
 # either "big" or "little").
 #
+# Also update the wal header checksum (since the wal header contents may
+# have changed).
+#
 proc log_checksum_writemagic {filename endian} {
   set val [expr {0x377f0682 | ($endian == "big" ? 1 : 0)}]
   set bin [binary format I $val]
@@ -123,6 +117,15 @@ proc log_checksum_writemagic {filename endian} {
   fconfigure $fd -encoding binary
   fconfigure $fd -translation binary
   puts -nonewline $fd $bin
+
+  seek $fd 0
+  set blob [read $fd 24]
+  set c1 0
+  set c2 0
+  wal_cksum $endian c1 c2 $blob 
+  seek $fd 24
+  puts -nonewline $fd [binary format II $c1 $c2]
+
   close $fd
 }
 
@@ -174,7 +177,7 @@ foreach endian {big little} {
     db close
 
     list [file size test2.db] [file size test2.db-wal]
-  } [list [expr 1024*3] [log_file_size 6 1024]]
+  } [list [expr 1024*3] [wal_file_size 6 1024]]
 
   # Verify that the checksums are valid for all frames and that they
   # are calculated by interpreting data in native byte-order.
@@ -211,7 +214,7 @@ foreach endian {big little} {
       INSERT INTO t1 VALUES(34, 'thirtyfour');
     }
     list [file size test.db] [file size test.db-wal]
-  } [list [expr 1024*3] [log_file_size 8 1024]]
+  } [list [expr 1024*3] [wal_file_size 8 1024]]
   for {set f 1} {$f <= 8} {incr f} {
     do_test walcksum-1.$endian.5.$f {
       log_checksum_verify test.db-wal $f $endian
@@ -235,7 +238,7 @@ foreach endian {big little} {
       INSERT INTO t1 VALUES(55, 'fiftyfive');
     } db2
     list [file size test.db] [file size test.db-wal]
-  } [list [expr 1024*3] [log_file_size 10 1024]]
+  } [list [expr 1024*3] [wal_file_size 10 1024]]
   for {set f 1} {$f <= 10} {incr f} {
     do_test walcksum-1.$endian.7.$f {
       log_checksum_verify test.db-wal $f $endian
@@ -351,7 +354,7 @@ do_test walcksum-3.1 {
   }
 
   file size test.db-wal
-} [log_file_size 1 1024]
+} [wal_file_size 1 1024]
 do_test walcksum-3.2 {
   file copy -force test.db-wal test2.db-wal
   file copy -force test.db test2.db
@@ -365,7 +368,7 @@ file copy -force test.db test2.db
 foreach incr {1 2 3 20 40 60 80 100 120 140 160 180 200 220 240 253 254 255} {
   do_test walcksum-3.3.$incr {
     set FAIL 0
-    for {set iOff 0} {$iOff < [log_file_size 1 1024]} {incr iOff} {
+    for {set iOff 0} {$iOff < [wal_file_size 1 1024]} {incr iOff} {
 
       file copy -force test.db-wal test2.db-wal
       set fd [open test2.db-wal r+]