branches/zip: Add UNIV_HASH_DEBUG for detecting multiple invocations

of HASH_DELETE().

HASH_ASSERT_VALID(), HASH_INVALIDATE(): New macros, used in HASH_DELETE()
and HASH_SEARCH().

buf_page_init_low(): Add HASH_INVALIDATE(bpage, hash);

buf_page_init(): Call buf_page_init_low() before HASH_INSERT(), so that
bpage->hash will not be invalidated.

buf/buf0buf.c

@@ -2028,9 +2028,9 @@ buf_page_init_low(
 	bpage->io_fix = BUF_IO_NONE;
 	bpage->buf_fix_count = 0;
 	bpage->freed_page_clock = 0;
-	// bpage->hash = (buf_page_t*) -1;
 	bpage->newest_modification = 0;
 	bpage->oldest_modification = 0;
+	HASH_INVALIDATE(bpage, hash);
 #ifdef UNIV_DEBUG_FILE_ACCESSES
 	bpage->file_page_was_freed = FALSE;
 #endif /* UNIV_DEBUG_FILE_ACCESSES */
@@ -2124,13 +2124,13 @@ buf_page_init(
 		ut_error;
 	}
 
+	buf_page_init_low(&block->page);
+
 	ut_ad(!block->page.in_zip_hash);
 	ut_ad(!block->page.in_page_hash);
 	ut_d(block->page.in_page_hash = TRUE);
 	HASH_INSERT(buf_page_t, hash, buf_pool->page_hash,
 		    buf_page_address_fold(space, offset), &block->page);
-
-	buf_page_init_low(&block->page);
 }
 
 /************************************************************************

include/hash0hash.h

@@ -98,6 +98,14 @@ do {\
 	}\
 } while (0)
 
+#ifdef UNIV_HASH_DEBUG
+# define HASH_ASSERT_VALID(DATA) ut_a((void*) (DATA) != (void*) -1)
+# define HASH_INVALIDATE(DATA, NAME) DATA->NAME = (void*) -1
+#else
+# define HASH_ASSERT_VALID(DATA) do {} while (0)
+# define HASH_INVALIDATE(DATA, NAME) do {} while (0)
+#endif
+
 /***********************************************************************
 Deletes a struct from a hash table. */
 
@@ -111,6 +119,7 @@ do {\
 	cell3333 = hash_get_nth_cell(TABLE, hash_calc_hash(FOLD, TABLE));\
 \
 	if (cell3333->node == DATA) {\
+		HASH_ASSERT_VALID(DATA->NAME);\
 		cell3333->node = DATA->NAME;\
 	} else {\
 		struct3333 = cell3333->node;\
@@ -123,6 +132,7 @@ do {\
 \
 		struct3333->NAME = DATA->NAME;\
 	}\
+	HASH_INVALIDATE(DATA, NAME);\
 } while (0)
 
 /***********************************************************************
@@ -144,11 +154,13 @@ Looks for a struct in a hash table. */
 	HASH_ASSERT_OWNED(TABLE, FOLD)\
 \
 	(DATA) = HASH_GET_FIRST(TABLE, hash_calc_hash(FOLD, TABLE));\
+	HASH_ASSERT_VALID(DATA);\
 \
 	while ((DATA) != NULL) {\
 		if (TEST) {\
 			break;\
 		} else {\
+			HASH_ASSERT_VALID(HASH_GET_NEXT(NAME, DATA));\
 			(DATA) = HASH_GET_NEXT(NAME, DATA);\
 		}\
 	}\

include/univ.i

@@ -87,6 +87,7 @@ memory is read outside the allocated blocks. */
 #define UNIV_DEBUG_FILE_ACCESSES		/* Debug .ibd file access
 						(field file_page_was_freed
 						in buf_page_t) */
+#define UNIV_HASH_DEBUG				/* debug HASH_ macros */
 #define UNIV_LIST_DEBUG				/* debug UT_LIST_ macros */
 #define UNIV_MEM_DEBUG				/* detect memory leaks etc */
 #define UNIV_IBUF_DEBUG				/* debug the insert buffer;