Bug #47012 archive tables are not upgradeable, and server crashes

       on any access

Archive engine for 5.1 (and latter) version uses a modified 
version of zlib (azlib). These two version are incompatible
so a proper upgrade is needed before tables created in 5.0 
can be used reliable.

This upgrade can be performed using repair. But due to lack 
of test its risky to allow upgrade for now. This patch addresses
only the crashing issue. Any attempt to repair will be blocked.

Eventually repair can be allowed to run through (which will also
cause an upgrade from older version to newer) but only after a 
thorough testing.

mysql-test/r/archive.result

@@ -12717,3 +12717,14 @@ COUNT(t1.a)
 729
 DROP TABLE t1;
 SET @@join_buffer_size= @save_join_buffer_size;
+SHOW CREATE TABLE t1;
+ERROR HY000: Table upgrade required. Please do "REPAIR TABLE `t1`" or dump/reload to fix it!
+SELECT * FROM t1;
+ERROR HY000: Table upgrade required. Please do "REPAIR TABLE `t1`" or dump/reload to fix it!
+INSERT INTO t1 (col1, col2) VALUES (1, "value");
+ERROR HY000: Table upgrade required. Please do "REPAIR TABLE `t1`" or dump/reload to fix it!
+REPAIR TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	repair	Error	Table upgrade required. Please do "REPAIR TABLE `t1`" or dump/reload to fix it!
+test.t1	repair	error	Corrupt
+DROP TABLE t1;

mysql-test/t/archive.test

@@ -1623,3 +1623,24 @@ INSERT INTO t1 VALUES('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'),
 SELECT COUNT(t1.a) FROM t1, t1 a, t1 b, t1 c, t1 d, t1 e;
 DROP TABLE t1;
 SET @@join_buffer_size= @save_join_buffer_size;
+
+#
+# BUG#47012 archive tables are not upgradeable, and server crashes on any access
+#
+let $MYSQLD_DATADIR= `SELECT @@datadir`;
+copy_file std_data/bug47012.frm $MYSQLD_DATADIR/test/t1.frm;
+copy_file std_data/bug47012.ARZ $MYSQLD_DATADIR/test/t1.ARZ;
+copy_file std_data/bug47012.ARM $MYSQLD_DATADIR/test/t1.ARM;
+
+--error ER_TABLE_NEEDS_UPGRADE
+SHOW CREATE TABLE t1;
+
+--error ER_TABLE_NEEDS_UPGRADE
+SELECT * FROM t1;
+
+--error ER_TABLE_NEEDS_UPGRADE
+INSERT INTO t1 (col1, col2) VALUES (1, "value");
+
+REPAIR TABLE t1;
+DROP TABLE t1;
+remove_file $MYSQLD_DATADIR/test/t1.ARM;

storage/archive/azio.c

@@ -69,7 +69,7 @@ int az_open (azio_stream *s, const char *path, int Flags, File fd)
   s->transparent = 0;
   s->mode = 'r';
   s->version = (unsigned char)az_magic[1]; /* this needs to be a define to version */
-  s->version = (unsigned char)az_magic[2]; /* minor version */
+  s->minor_version= (unsigned char) az_magic[2]; /* minor version */
 
   /*
     We do our own version of append by nature. 
@@ -352,10 +352,19 @@ void read_header(azio_stream *s, unsigned char *buffer)
     s->comment_length= (unsigned int)uint4korr(buffer + AZ_COMMENT_LENGTH_POS);
     s->dirty= (unsigned int)buffer[AZ_DIRTY_POS];
   }
-  else
+  else if (buffer[0] == gz_magic[0]  && buffer[1] == gz_magic[1])
   {
-    DBUG_ASSERT(buffer[0] == az_magic[0]  && buffer[1] == az_magic[1]);
-    return;
+    /*
+      Set version number to previous version (2).
+    */
+    s->version= (unsigned char) 2;
+  } else {
+    /*
+      Unknown version.
+      Most probably due to a corrupt archive.
+    */
+    s->dirty= AZ_STATE_DIRTY;
+    s->z_err= Z_VERSION_ERROR;
   }
 }
 

storage/archive/ha_archive.cc

@@ -360,6 +360,12 @@ ARCHIVE_SHARE *ha_archive::get_share(const char *table_name, int *rc)
     stats.auto_increment_value= archive_tmp.auto_increment + 1;
     share->rows_recorded= (ha_rows)archive_tmp.rows;
     share->crashed= archive_tmp.dirty;
+    /*
+      If archive version is less than 3, It should be upgraded before
+      use.
+    */
+    if (archive_tmp.version < ARCHIVE_VERSION)
+      *rc= HA_ERR_TABLE_NEEDS_UPGRADE;
     azclose(&archive_tmp);
 
     VOID(my_hash_insert(&archive_open_tables, (uchar*) share));
@@ -491,7 +497,15 @@ int ha_archive::open(const char *name, int mode, uint open_options)
                       (open_options & HA_OPEN_FOR_REPAIR) ? "yes" : "no"));
   share= get_share(name, &rc);
 
-  if (rc == HA_ERR_CRASHED_ON_USAGE && !(open_options & HA_OPEN_FOR_REPAIR))
+ /*
+    Allow open on crashed table in repair mode only.
+    Block open on 5.0 ARCHIVE table. Though we have almost all
+    routines to access these tables, they were not well tested.
+    For now we have to refuse to open such table to avoid
+    potential data loss.
+  */
+  if ((rc == HA_ERR_CRASHED_ON_USAGE && !(open_options & HA_OPEN_FOR_REPAIR))
+      ||  rc == HA_ERR_TABLE_NEEDS_UPGRADE)
   {
     /* purecov: begin inspected */
     free_share();