Fixed bug in how FAST and CHANGED worked

Docs/manual.texi:
  Removed bugs from manual; Updated CHECK TABLE

Docs/manual.texi

@@ -12021,6 +12021,7 @@ Website}.
 @findex SET PASSWORD statement
 @cindex setting, passwords
 @node Passwords, Access denied, Adding users, Privilege system
+@section Setting passwords
 
 In most cases you should use @code{GRANT} to set up your users/passwords,
 so the following only applies for advanced users. @xref{GRANT, , @code{GRANT}}.
@@ -16653,7 +16654,7 @@ This is an "RSA Data Security, Inc. MD5 Message-Digest Algorithm".
 @item LAST_INSERT_ID([expr])
 Returns the last automatically generated value that was inserted into an
 @code{AUTO_INCREMENT} column.
-@xref{mysql_insert_id,, @code{mysql_insert_id()}}:
+@xref{mysql_insert_id,, @code{mysql_insert_id()}}.
 
 @example
 mysql> select LAST_INSERT_ID();
@@ -16872,7 +16873,7 @@ mysql> select student_name, AVG(test_score)
 @itemx MAX(expr)
 Returns the minimum or maximum value of @code{expr}.  @code{MIN()} and
 @code{MAX()} may take a string argument; in such cases they return the
-minimum or maximum string value. @xref{MySQL indexes}:
+minimum or maximum string value. @xref{MySQL indexes}.
 
 @example
 mysql> select student_name, MIN(test_score), MAX(test_score)
@@ -17813,12 +17814,34 @@ The different check types stand for the following:
 
 @multitable @columnfractions .20 .80
 @item @strong{Type} @tab @strong{Meaning}
-@item @code{QUICK} @tab Don't scan the rows for fixed size record tables.
+@item @code{QUICK} @tab Don't scan the rows to check for wrong links.
 @item @code{FAST}  @tab Only check tables which haven't been closed properly.
 @item @code{CHANGED} @tab Only check tables which have been changed since last check or haven't been closed properly.
 @item @code{EXTENDED} @tab Do a full key lookup for all keys for each row.  This ensures that the table is 100 % consistent, but will take a long time!
 @end multitable
 
+If a table is corrupted, then it's most likely that the problem is in
+the indexes and not in the data part.  All of the above check types
+checks the indexes throughly and should thus find most errors.
+
+If you just want to check a table that you assume is ok, you should use
+no check options or the @code{QUICK} option. The later should be used
+when you are in a hurry and can take the very small risk that
+@code{QUICK} didn't find an error in the data file (In most cases
+@strong{MySQL} should find, under normal usage, any error in the data
+file. If this happens then the table will be marked as 'corrupted'.
+
+@code{FAST} and @code{CHANGED} are mostly intended to be used from a
+script (for example to be executed from cron) if you want to check your
+table from time to time. In most cases you @code{FAST} is to be prefered
+over @code{CHANGED}.  (The only case when it isn't is when you suspect a
+bug you have found a bug in the @code{MyISAM} code.).
+
+@code{EXTENDED} is only to be used after you have run a normal check but
+still get strange errors from a table when @strong{MySQL} tries to
+update a row or find a row by key (this is VERY unlikely to happen if a
+normal check has succeeded!).
+
 @findex BACKUP TABLE
 @node BACKUP TABLE, RESTORE TABLE, CHECK TABLE, Reference
 @section @code{BACKUP TABLE} syntax
@@ -43265,17 +43288,6 @@ All new development is concentrated to @strong{MySQL}.
 @page
 @c This node name is special
 
-@ifset nusphere
-@cindex GNU General Public License
-@cindex licenses, GNU General Public License
-@node GPL license, LGPL license, Unireg, Top
-@appendix GNU General Public License
-
-The GPL License can be found at ...
-
-@end ifset
-
-@ifclear nusphere
 @node GPL license, LGPL license, Unireg, Top
 @appendix GNU General Public License
 

sql/ha_myisam.cc

@@ -250,10 +250,11 @@ int ha_myisam::check(THD* thd, HA_CHECK_OPT* check_opt)
 
   if (!mi_is_crashed(file) &&
       (((param.testflag & T_CHECK_ONLY_CHANGED) &&
-	(share->state.changed & (STATE_CHANGED | STATE_CRASHED |
-				 STATE_CRASHED_ON_REPAIR)) &&
+	!(share->state.changed & (STATE_CHANGED | STATE_CRASHED |
+				  STATE_CRASHED_ON_REPAIR)) &&
 	share->state.open_count == 0) ||
-       ((param.testflag & T_FAST) && share->state.open_count == 0)))
+       ((param.testflag & T_FAST) && (share->state.open_count ==
+				      (share->global_changed ? 1 : 0)))))
     return HA_ADMIN_ALREADY_DONE;
 
   error = chk_size(&param, file);