Bug #11752069 (former bug 43152)

Assertion `bitmap_is_set_all(&table->s->all_set)' failed in
handler::ha_reset

This assertion could be triggered if two connections simultaneously
executed two bitmap test functions on the same bitmap. For example,
the assertion could be triggered if one connection executed UPDATE
while a second connection executed SELECT on the same table.

Even if bitmap test functions have read-only semantics and have
const bitmaps as parameter, several of them modified the internal
state of the bitmap. With interleaved execution of two such functions
it was possible for one function to modify the state of the same
bitmap that the other function had just modified. This lead to an
inconsistent state and could trigger the assert.

Internally the bitmap uses 32 bit words for storage. Since bitmaps
can contain any number of bits, the last word in the bitmap may
not be fully used. A 32 bit mask is maintained where a bit is set
if the corresponding bit in the last bitmap word is unused.
The problem was that several test functions applied this mask to
the last word. Sometimes the mask was negated and used to zero out
the remainder of the last word and sometimes the mask was used as-is
to fill the remainder of the last word with 1's. This meant that if
a function first used the negated mask and another function then
used the mask as-is (or vice-versa), the first function would then
get the wrong result.

This patch fixes the problem by changing the implementation of
9 bitmap functions that modified the bitmap state even if the 
bitmap was declared const. These functions now preserve the
internal state of the bitmap. This makes it possible for
two connections to concurrently execute two of these functions
on the same bitmap without issues.

The patch also removes dead testing code from my_bitmap.c.
These tests have already been moved to unittest/mysys/bitmap-t.c.
Existing test coverage of my_bitmap has been extended.

No MTR test case added as this would require adding several sync
points to the bitmap functions. The patch has been tested with
a non-deterministic test case posted on the bug report.


include/my_bit.h:
  Removed my_count_bits_ushort() which is not needed anymore.
  Added my_count_bits_uint32().
unittest/mysys/bitmap-t.c:
  Extended test coverage of my_bitmap.

include/my_bit.h

+/* Copyright (c) 2007, 2011, Oracle and/or its affiliates. All rights reserved.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */
+
 /*
   Some useful bit functions
 */
@@ -42,9 +57,12 @@ STATIC_INLINE uint my_count_bits(ulonglong v)
 #endif
 }
 
-STATIC_INLINE uint my_count_bits_ushort(ushort v)
+STATIC_INLINE uint my_count_bits_uint32(uint32 v)
 {
-  return _my_bits_nbits[v];
+  return (uint) (uchar) (_my_bits_nbits[(uchar)  v] +
+                         _my_bits_nbits[(uchar) (v >> 8)] +
+                         _my_bits_nbits[(uchar) (v >> 16)] +
+                         _my_bits_nbits[(uchar) (v >> 24)]);
 }
 
 
@@ -104,6 +122,6 @@ extern uint32 my_round_up_to_next_power(uint32 v);
 uint32 my_clear_highest_bit(uint32 v);
 uint32 my_reverse_bits(uint32 key);
 extern uint my_count_bits(ulonglong v);
-extern uint my_count_bits_ushort(ushort v);
+extern uint my_count_bits_uint32(uint32 v);
 #endif /* HAVE_INLINE */
 C_MODE_END

include/my_bitmap.h

-/* Copyright (C) 2000 MySQL AB
+/* Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -149,9 +149,10 @@ bitmap_is_set(const MY_BITMAP *map,uint bit)
 
 static inline my_bool bitmap_cmp(const MY_BITMAP *map1, const MY_BITMAP *map2)
 {
-  *(map1)->last_word_ptr|= (map1)->last_word_mask;
-  *(map2)->last_word_ptr|= (map2)->last_word_mask;
-  return memcmp((map1)->bitmap, (map2)->bitmap, 4*no_words_in_map((map1)))==0;
+  if (memcmp(map1->bitmap, map2->bitmap, 4*(no_words_in_map(map1)-1)) != 0)
+    return FALSE;
+  return ((*map1->last_word_ptr | map1->last_word_mask) ==
+          (*map2->last_word_ptr | map2->last_word_mask));
 }
 
 #define bitmap_clear_all(MAP) \

mysys/my_bitmap.c

-/* Copyright (C) 2000 MySQL AB
+/* Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -91,6 +91,7 @@ static inline void bitmap_lock(MY_BITMAP *map __attribute__((unused)))
 #endif
 }
 
+
 static inline void bitmap_unlock(MY_BITMAP *map __attribute__((unused)))
 {
 #ifdef THREAD
@@ -100,6 +101,46 @@ static inline void bitmap_unlock(MY_BITMAP *map __attribute__((unused)))
 }
 
 
+static inline uint get_first_set(uint32 value, uint word_pos)
+{
+  uchar *byte_ptr= (uchar*)&value;
+  uchar byte_value;
+  uint byte_pos, bit_pos;
+
+  for (byte_pos=0; byte_pos < 4; byte_pos++, byte_ptr++)
+  {
+    byte_value= *byte_ptr;
+    if (byte_value)
+    {
+      for (bit_pos=0; ; bit_pos++)
+        if (byte_value & (1 << bit_pos))
+          return (word_pos*32) + (byte_pos*8) + bit_pos;
+    }
+  }
+  return MY_BIT_NONE;
+}
+
+
+static inline uint get_first_not_set(uint32 value, uint word_pos)
+{
+  uchar *byte_ptr= (uchar*)&value;
+  uchar byte_value;
+  uint byte_pos, bit_pos;
+
+  for (byte_pos=0; byte_pos < 4; byte_pos++, byte_ptr++)
+  {
+    byte_value= *byte_ptr;
+    if (byte_value != 0xFF)
+    {
+      for (bit_pos=0; ; bit_pos++)
+        if (!(byte_value & (1 << bit_pos)))
+          return (word_pos*32) + (byte_pos*8) + bit_pos;
+    }
+  }
+  return MY_BIT_NONE;
+}
+
+
 my_bool bitmap_init(MY_BITMAP *map, my_bitmap_map *buf, uint n_bits,
 		    my_bool thread_safe __attribute__((unused)))
 {
@@ -259,7 +300,7 @@ void bitmap_set_prefix(MY_BITMAP *map, uint prefix_size)
     memset(m, 0xff, prefix_bytes);
   m+= prefix_bytes;
   if ((prefix_bits= prefix_size & 7))
-    *m++= (1 << prefix_bits)-1;
+    *(m++)= (1 << prefix_bits)-1;
   if ((d= no_bytes_in_map(map)-prefix_bytes))
     bzero(m, d);
 }
@@ -267,28 +308,43 @@ void bitmap_set_prefix(MY_BITMAP *map, uint prefix_size)
 
 my_bool bitmap_is_prefix(const MY_BITMAP *map, uint prefix_size)
 {
-  uint prefix_bits= prefix_size & 0x7, res;
-  uchar *m= (uchar*)map->bitmap;
-  uchar *end_prefix= m+prefix_size/8;
-  uchar *end;
-  DBUG_ASSERT(m && prefix_size <= map->n_bits);
-  end= m+no_bytes_in_map(map);
-
-  while (m < end_prefix)
-    if (*m++ != 0xff)
-      return 0;
-
-  *map->last_word_ptr&= ~map->last_word_mask; /*Clear bits*/
-  res= 0;
-  if (prefix_bits && *m++ != (1 << prefix_bits)-1)
-    goto ret;
-
-  while (m < end)
-    if (*m++ != 0)
-      goto ret;
-  res= 1;
-ret:
-  return res; 
+  uint prefix_bits= prefix_size % 32;
+  my_bitmap_map *word_ptr= map->bitmap, last_word;
+  my_bitmap_map *end_prefix= word_ptr + prefix_size / 32;
+  DBUG_ASSERT(word_ptr && prefix_size <= map->n_bits);
+
+  /* 1: Words that should be filled with 1 */
+  for (; word_ptr < end_prefix; word_ptr++)
+    if (*word_ptr != 0xFFFFFFFF)
+      return FALSE;
+
+  last_word= *map->last_word_ptr & ~map->last_word_mask;
+
+  /* 2: Word which contains the end of the prefix (if any) */
+  if (prefix_bits)
+  {
+    if (word_ptr == map->last_word_ptr)
+      return uint4korr((uchar*)&last_word) == (uint32)((1 << prefix_bits) - 1);
+    else if (uint4korr((uchar*)word_ptr) != (uint32)((1 << prefix_bits) - 1))
+      return FALSE;
+    word_ptr++;
+  }
+
+  /* 3: Words that should be filled with 0 */
+  for (; word_ptr < map->last_word_ptr; word_ptr++)
+    if (*word_ptr != 0)
+      return FALSE;
+
+  /*
+    We can end up here in two situations:
+    1) We went through the whole bitmap in step 1. This will happen if the
+       whole bitmap is filled with 1 and prefix_size is a multiple of 32
+       (i.e. the prefix does not end in the middle of a word).
+       In this case word_ptr will be larger than map->last_word_ptr.
+    2) We have gone through steps 1-3 and just need to check that also
+       the last word is 0.
+  */
+  return word_ptr > map->last_word_ptr || last_word == 0;
 }
 
 
@@ -296,10 +352,12 @@ my_bool bitmap_is_set_all(const MY_BITMAP *map)
 {
   my_bitmap_map *data_ptr= map->bitmap;
   my_bitmap_map *end= map->last_word_ptr;
-  *map->last_word_ptr |= map->last_word_mask;
-  for (; data_ptr <= end; data_ptr++)
+
+  for (; data_ptr < end; data_ptr++)
     if (*data_ptr != 0xFFFFFFFF)
       return FALSE;
+  if ((*map->last_word_ptr | map->last_word_mask) != 0xFFFFFFFF)
+    return FALSE;
   return TRUE;
 }
 
@@ -307,13 +365,13 @@ my_bool bitmap_is_set_all(const MY_BITMAP *map)
 my_bool bitmap_is_clear_all(const MY_BITMAP *map)
 {
   my_bitmap_map *data_ptr= map->bitmap;
-  my_bitmap_map *end;
-  if (*map->last_word_ptr & ~map->last_word_mask)
-    return FALSE;
-  end= map->last_word_ptr;
+  my_bitmap_map *end= map->last_word_ptr;
+
   for (; data_ptr < end; data_ptr++)
     if (*data_ptr)
       return FALSE;
+  if (*map->last_word_ptr & ~map->last_word_mask)
+    return FALSE;
   return TRUE;
 }
 
@@ -327,14 +385,14 @@ my_bool bitmap_is_subset(const MY_BITMAP *map1, const MY_BITMAP *map2)
               map1->n_bits==map2->n_bits);
 
   end= map1->last_word_ptr;
-  *map1->last_word_ptr &= ~map1->last_word_mask;
-  *map2->last_word_ptr &= ~map2->last_word_mask;
-  while (m1 <= end)
-  {
-    if ((*m1++) & ~(*m2++))
-      return 0;
-  }
-  return 1;
+  for (; m1 < end; m1++, m2++)
+    if (*m1 & ~(*m2))
+      return FALSE;
+
+  if ((*map1->last_word_ptr & ~map1->last_word_mask) &
+      ~(*map2->last_word_ptr & ~map2->last_word_mask))
+    return FALSE;
+  return TRUE;
 }
 
 /* True if bitmaps has any common bits */
@@ -347,14 +405,14 @@ my_bool bitmap_is_overlapping(const MY_BITMAP *map1, const MY_BITMAP *map2)
               map1->n_bits==map2->n_bits);
 
   end= map1->last_word_ptr;
-  *map1->last_word_ptr &= ~map1->last_word_mask;
-  *map2->last_word_ptr &= ~map2->last_word_mask;
-  while (m1 <= end)
-  {
-    if ((*m1++) & (*m2++))
-      return 1;
-  }
-  return 0;
+  for (; m1 < end; m1++, m2++)
+    if (*m1 & *m2)
+      return TRUE;
+
+  if ((*map1->last_word_ptr & ~map1->last_word_mask) &
+      (*map2->last_word_ptr & ~map2->last_word_mask))
+    return TRUE;
+  return FALSE;
 }
 
 
@@ -366,15 +424,17 @@ void bitmap_intersect(MY_BITMAP *map, const MY_BITMAP *map2)
   DBUG_ASSERT(map->bitmap && map2->bitmap);
 
   end= to+min(len,len2);
-  *map2->last_word_ptr&= ~map2->last_word_mask; /*Clear last bits in map2*/
-  while (to < end)
-    *to++ &= *from++;
+  for (; to < end; to++, from++)
+    *to &= *from;
+
+  if (len >= len2)
+    map->bitmap[len2 - 1] &= ~map2->last_word_mask;
 
   if (len2 < len)
   {
     end+=len-len2;
-    while (to < end)
-      *to++=0;
+    for (; to < end; to++)
+      *to= 0;
   }
 }
 
@@ -405,8 +465,8 @@ void bitmap_set_above(MY_BITMAP *map, uint from_byte, uint use_bit)
   uchar *to= (uchar *)map->bitmap + from_byte;
   uchar *end= (uchar *)map->bitmap + (map->n_bits+7)/8;
 
-  while (to < end)
-    *to++= use_byte;
+  for (; to < end; to++)
+    *to= use_byte;
 }
 
 
@@ -415,59 +475,60 @@ void bitmap_subtract(MY_BITMAP *map, const MY_BITMAP *map2)
   my_bitmap_map *to= map->bitmap, *from= map2->bitmap, *end;
   DBUG_ASSERT(map->bitmap && map2->bitmap &&
               map->n_bits==map2->n_bits);
-
   end= map->last_word_ptr;
 
-  while (to <= end)
-    *to++ &= ~(*from++);
+  for (; to <= end; to++, from++)
+    *to &= ~(*from);
 }
 
 
 void bitmap_union(MY_BITMAP *map, const MY_BITMAP *map2)
 {
   my_bitmap_map *to= map->bitmap, *from= map2->bitmap, *end;
-
   DBUG_ASSERT(map->bitmap && map2->bitmap &&
               map->n_bits==map2->n_bits);
   end= map->last_word_ptr;
 
-  while (to <= end)
-    *to++ |= *from++;
+  for (; to <= end; to++, from++)
+    *to |= *from;
 }
 
 
 void bitmap_xor(MY_BITMAP *map, const MY_BITMAP *map2)
 {
-  my_bitmap_map *to= map->bitmap, *from= map2->bitmap, *end= map->last_word_ptr;
+  my_bitmap_map *to= map->bitmap, *from= map2->bitmap, *end;
   DBUG_ASSERT(map->bitmap && map2->bitmap &&
               map->n_bits==map2->n_bits);
-  while (to <= end)
-    *to++ ^= *from++;
+  end= map->last_word_ptr;
+
+  for (; to <= end; to++, from++)
+    *to ^= *from;
 }
 
 
 void bitmap_invert(MY_BITMAP *map)
 {
   my_bitmap_map *to= map->bitmap, *end;
-
   DBUG_ASSERT(map->bitmap);
   end= map->last_word_ptr;
 
-  while (to <= end)
-    *to++ ^= 0xFFFFFFFF;
+  for (; to <= end; to++)
+    *to ^= 0xFFFFFFFF;
 }
 
 
 uint bitmap_bits_set(const MY_BITMAP *map)
 {
-  uchar *m= (uchar*)map->bitmap;
-  uchar *end= m + no_bytes_in_map(map);
+  my_bitmap_map *data_ptr= map->bitmap;
+  my_bitmap_map *end= map->last_word_ptr;
   uint res= 0;
-
   DBUG_ASSERT(map->bitmap);
-  *map->last_word_ptr&= ~map->last_word_mask; /*Reset last bits to zero*/
-  while (m < end)
-    res+= my_count_bits_ushort(*m++);
+
+  for (; data_ptr < end; data_ptr++)
+    res+= my_count_bits_uint32(*data_ptr);
+
+  /*Reset last bits to zero*/
+  res+= my_count_bits_uint32(*map->last_word_ptr & ~map->last_word_mask);
   return res;
 }
 
@@ -475,76 +536,44 @@ uint bitmap_bits_set(const MY_BITMAP *map)
 void bitmap_copy(MY_BITMAP *map, const MY_BITMAP *map2)
 {
   my_bitmap_map *to= map->bitmap, *from= map2->bitmap, *end;
-
   DBUG_ASSERT(map->bitmap && map2->bitmap &&
               map->n_bits==map2->n_bits);
   end= map->last_word_ptr;
-  while (to <= end)
-    *to++ = *from++;
+
+  for (; to <= end; to++, from++)
+    *to = *from;
 }
 
 
 uint bitmap_get_first_set(const MY_BITMAP *map)
 {
-  uchar *byte_ptr;
-  uint i,j,k;
+  uint word_pos;
   my_bitmap_map *data_ptr, *end= map->last_word_ptr;
 
   DBUG_ASSERT(map->bitmap);
   data_ptr= map->bitmap;
-  *map->last_word_ptr &= ~map->last_word_mask;
 
-  for (i=0; data_ptr <= end; data_ptr++, i++)
-  {
+  for (word_pos=0; data_ptr < end; data_ptr++, word_pos++)
     if (*data_ptr)
-    {
-      byte_ptr= (uchar*)data_ptr;
-      for (j=0; ; j++, byte_ptr++)
-      {
-        if (*byte_ptr)
-        {
-          for (k=0; ; k++)
-          {
-            if (*byte_ptr & (1 << k))
-              return (i*32) + (j*8) + k;
-          }
-        }
-      }
-    }
-  }
-  return MY_BIT_NONE;
+      return get_first_set(*data_ptr, word_pos);
+
+  return get_first_set(*map->last_word_ptr & ~map->last_word_mask, word_pos);
 }
 
 
 uint bitmap_get_first(const MY_BITMAP *map)
 {
-  uchar *byte_ptr;
-  uint i,j,k;
+  uint word_pos;
   my_bitmap_map *data_ptr, *end= map->last_word_ptr;
 
   DBUG_ASSERT(map->bitmap);
   data_ptr= map->bitmap;
-  *map->last_word_ptr|= map->last_word_mask;
 
-  for (i=0; data_ptr <= end; data_ptr++, i++)
-  {
+  for (word_pos=0; data_ptr < end; data_ptr++, word_pos++)
     if (*data_ptr != 0xFFFFFFFF)
-    {
-      byte_ptr= (uchar*)data_ptr;
-      for (j=0; ; j++, byte_ptr++)
-      {
-        if (*byte_ptr != 0xFF)
-        {
-          for (k=0; ; k++)
-          {
-            if (!(*byte_ptr & (1 << k)))
-              return (i*32) + (j*8) + k;
-          }
-        }
-      }
-    }
-  }
-  return MY_BIT_NONE;
+      return get_first_not_set(*data_ptr, word_pos);
+
+  return get_first_not_set(*map->last_word_ptr | map->last_word_mask, word_pos);
 }
 
 
@@ -752,375 +781,3 @@ void bitmap_lock_flip_bit(MY_BITMAP *map, uint bitmap_bit)
   bitmap_unlock(map);
 }
 #endif
-#ifdef MAIN
-
-uint get_rand_bit(uint bitsize)
-{
-  return (rand() % bitsize);
-}
-
-bool test_set_get_clear_bit(MY_BITMAP *map, uint bitsize)
-{
-  uint i, test_bit;
-  uint no_loops= bitsize > 128 ? 128 : bitsize;
-  for (i=0; i < no_loops; i++)
-  {
-    test_bit= get_rand_bit(bitsize);
-    bitmap_set_bit(map, test_bit);
-    if (!bitmap_is_set(map, test_bit))
-      goto error1;
-    bitmap_clear_bit(map, test_bit);
-    if (bitmap_is_set(map, test_bit))
-      goto error2;
-  }
-  return FALSE;
-error1:
-  printf("Error in set bit, bit %u, bitsize = %u", test_bit, bitsize);
-  return TRUE;
-error2:
-  printf("Error in clear bit, bit %u, bitsize = %u", test_bit, bitsize);
-  return TRUE;
-}
-
-bool test_flip_bit(MY_BITMAP *map, uint bitsize)
-{
-  uint i, test_bit;
-  uint no_loops= bitsize > 128 ? 128 : bitsize;
-  for (i=0; i < no_loops; i++)
-  {
-    test_bit= get_rand_bit(bitsize);
-    bitmap_flip_bit(map, test_bit);
-    if (!bitmap_is_set(map, test_bit))
-      goto error1;
-    bitmap_flip_bit(map, test_bit);
-    if (bitmap_is_set(map, test_bit))
-      goto error2;
-  }
-  return FALSE;
-error1:
-  printf("Error in flip bit 1, bit %u, bitsize = %u", test_bit, bitsize);
-  return TRUE;
-error2:
-  printf("Error in flip bit 2, bit %u, bitsize = %u", test_bit, bitsize);
-  return TRUE;
-}
-
-bool test_operators(MY_BITMAP *map __attribute__((unused)),
-                    uint bitsize __attribute__((unused)))
-{
-  return FALSE;
-}
-
-bool test_get_all_bits(MY_BITMAP *map, uint bitsize)
-{
-  uint i;
-  bitmap_set_all(map);
-  if (!bitmap_is_set_all(map))
-    goto error1;
-  if (!bitmap_is_prefix(map, bitsize))
-    goto error5;
-  bitmap_clear_all(map);
-  if (!bitmap_is_clear_all(map))
-    goto error2;
-  if (!bitmap_is_prefix(map, 0))
-    goto error6;
-  for (i=0; i<bitsize;i++)
-    bitmap_set_bit(map, i);
-  if (!bitmap_is_set_all(map))
-    goto error3;
-  for (i=0; i<bitsize;i++)
-    bitmap_clear_bit(map, i);
-  if (!bitmap_is_clear_all(map))
-    goto error4;
-  return FALSE;
-error1:
-  printf("Error in set_all, bitsize = %u", bitsize);
-  return TRUE;
-error2:
-  printf("Error in clear_all, bitsize = %u", bitsize);
-  return TRUE;
-error3:
-  printf("Error in bitmap_is_set_all, bitsize = %u", bitsize);
-  return TRUE;
-error4:
-  printf("Error in bitmap_is_clear_all, bitsize = %u", bitsize);
-  return TRUE;
-error5:
-  printf("Error in set_all through set_prefix, bitsize = %u", bitsize);
-  return TRUE;
-error6:
-  printf("Error in clear_all through set_prefix, bitsize = %u", bitsize);
-  return TRUE;
-}
-
-bool test_compare_operators(MY_BITMAP *map, uint bitsize)
-{
-  uint i, j, test_bit1, test_bit2, test_bit3,test_bit4;
-  uint no_loops= bitsize > 128 ? 128 : bitsize;
-  MY_BITMAP map2_obj, map3_obj;
-  MY_BITMAP *map2= &map2_obj, *map3= &map3_obj;
-  my_bitmap_map map2buf[1024];
-  my_bitmap_map map3buf[1024];
-  bitmap_init(&map2_obj, map2buf, bitsize, FALSE);
-  bitmap_init(&map3_obj, map3buf, bitsize, FALSE);
-  bitmap_clear_all(map2);
-  bitmap_clear_all(map3);
-  for (i=0; i < no_loops; i++)
-  {
-    test_bit1=get_rand_bit(bitsize);
-    bitmap_set_prefix(map, test_bit1);
-    test_bit2=get_rand_bit(bitsize);
-    bitmap_set_prefix(map2, test_bit2);
-    bitmap_intersect(map, map2);
-    test_bit3= test_bit2 < test_bit1 ? test_bit2 : test_bit1;
-    bitmap_set_prefix(map3, test_bit3);
-    if (!bitmap_cmp(map, map3))
-      goto error1;
-    bitmap_clear_all(map);
-    bitmap_clear_all(map2);
-    bitmap_clear_all(map3);
-    test_bit1=get_rand_bit(bitsize);
-    test_bit2=get_rand_bit(bitsize);
-    test_bit3=get_rand_bit(bitsize);
-    bitmap_set_prefix(map, test_bit1);
-    bitmap_set_prefix(map2, test_bit2);
-    test_bit3= test_bit2 > test_bit1 ? test_bit2 : test_bit1;
-    bitmap_set_prefix(map3, test_bit3);
-    bitmap_union(map, map2);
-    if (!bitmap_cmp(map, map3))
-      goto error2;
-    bitmap_clear_all(map);
-    bitmap_clear_all(map2);
-    bitmap_clear_all(map3);
-    test_bit1=get_rand_bit(bitsize);
-    test_bit2=get_rand_bit(bitsize);
-    test_bit3=get_rand_bit(bitsize);
-    bitmap_set_prefix(map, test_bit1);
-    bitmap_set_prefix(map2, test_bit2);
-    bitmap_xor(map, map2);
-    test_bit3= test_bit2 > test_bit1 ? test_bit2 : test_bit1;
-    test_bit4= test_bit2 < test_bit1 ? test_bit2 : test_bit1;
-    bitmap_set_prefix(map3, test_bit3);
-    for (j=0; j < test_bit4; j++)
-      bitmap_clear_bit(map3, j);
-    if (!bitmap_cmp(map, map3))
-      goto error3;
-    bitmap_clear_all(map);
-    bitmap_clear_all(map2);
-    bitmap_clear_all(map3);
-    test_bit1=get_rand_bit(bitsize);
-    test_bit2=get_rand_bit(bitsize);
-    test_bit3=get_rand_bit(bitsize);
-    bitmap_set_prefix(map, test_bit1);
-    bitmap_set_prefix(map2, test_bit2);
-    bitmap_subtract(map, map2);
-    if (test_bit2 < test_bit1)
-    {
-      bitmap_set_prefix(map3, test_bit1);
-      for (j=0; j < test_bit2; j++)
-        bitmap_clear_bit(map3, j);
-    }
-    if (!bitmap_cmp(map, map3))
-      goto error4;
-    bitmap_clear_all(map);
-    bitmap_clear_all(map2);
-    bitmap_clear_all(map3);
-    test_bit1=get_rand_bit(bitsize);
-    bitmap_set_prefix(map, test_bit1);
-    bitmap_invert(map);
-    bitmap_set_all(map3);
-    for (j=0; j < test_bit1; j++)
-      bitmap_clear_bit(map3, j);
-    if (!bitmap_cmp(map, map3))
-      goto error5;
-    bitmap_clear_all(map);
-    bitmap_clear_all(map3);
-  }
-  return FALSE;
-error1:
-  printf("intersect error  bitsize=%u,size1=%u,size2=%u", bitsize,
-  test_bit1,test_bit2);
-  return TRUE;
-error2:
-  printf("union error  bitsize=%u,size1=%u,size2=%u", bitsize,
-  test_bit1,test_bit2);
-  return TRUE;
-error3:
-  printf("xor error  bitsize=%u,size1=%u,size2=%u", bitsize,
-  test_bit1,test_bit2);
-  return TRUE;
-error4:
-  printf("subtract error  bitsize=%u,size1=%u,size2=%u", bitsize,
-  test_bit1,test_bit2);
-  return TRUE;
-error5:
-  printf("invert error  bitsize=%u,size=%u", bitsize,
-  test_bit1);
-  return TRUE;
-}
-
-bool test_count_bits_set(MY_BITMAP *map, uint bitsize)
-{
-  uint i, bit_count=0, test_bit;
-  uint no_loops= bitsize > 128 ? 128 : bitsize;
-  for (i=0; i < no_loops; i++)
-  {
-    test_bit=get_rand_bit(bitsize);
-    if (!bitmap_is_set(map, test_bit))
-    {
-      bitmap_set_bit(map, test_bit);
-      bit_count++;
-    }
-  }
-  if (bit_count==0 && bitsize > 0)
-    goto error1;
-  if (bitmap_bits_set(map) != bit_count)
-    goto error2;
-  return FALSE;
-error1:
-  printf("No bits set  bitsize = %u", bitsize);
-  return TRUE;
-error2:
-  printf("Wrong count of bits set, bitsize = %u", bitsize);
-  return TRUE;
-}
-
-bool test_get_first_bit(MY_BITMAP *map, uint bitsize)
-{
-  uint i, test_bit;
-  uint no_loops= bitsize > 128 ? 128 : bitsize;
-  for (i=0; i < no_loops; i++)
-  {
-    test_bit=get_rand_bit(bitsize);
-    bitmap_set_bit(map, test_bit);
-    if (bitmap_get_first_set(map) != test_bit)
-      goto error1;
-    bitmap_set_all(map);
-    bitmap_clear_bit(map, test_bit);
-    if (bitmap_get_first(map) != test_bit)
-      goto error2;
-    bitmap_clear_all(map);
-  }
-  return FALSE;
-error1:
-  printf("get_first_set error bitsize=%u,prefix_size=%u",bitsize,test_bit);
-  return TRUE;
-error2:
-  printf("get_first error bitsize= %u, prefix_size= %u",bitsize,test_bit);
-  return TRUE;
-}
-
-bool test_get_next_bit(MY_BITMAP *map, uint bitsize)
-{
-  uint i, j, test_bit;
-  uint no_loops= bitsize > 128 ? 128 : bitsize;
-  for (i=0; i < no_loops; i++)
-  {
-    test_bit=get_rand_bit(bitsize);
-    for (j=0; j < test_bit; j++)
-      bitmap_set_next(map);
-    if (!bitmap_is_prefix(map, test_bit))
-      goto error1;
-    bitmap_clear_all(map);
-  }
-  return FALSE;
-error1:
-  printf("get_next error  bitsize= %u, prefix_size= %u", bitsize,test_bit);
-  return TRUE;
-}
-
-bool test_prefix(MY_BITMAP *map, uint bitsize)
-{
-  uint i, j, test_bit;
-  uint no_loops= bitsize > 128 ? 128 : bitsize;
-  for (i=0; i < no_loops; i++)
-  {
-    test_bit=get_rand_bit(bitsize);
-    bitmap_set_prefix(map, test_bit);
-    if (!bitmap_is_prefix(map, test_bit))
-      goto error1;
-    bitmap_clear_all(map);
-    for (j=0; j < test_bit; j++)
-      bitmap_set_bit(map, j);
-    if (!bitmap_is_prefix(map, test_bit))
-      goto error2;
-    bitmap_set_all(map);
-    for (j=bitsize - 1; ~(j-test_bit); j--)
-      bitmap_clear_bit(map, j);
-    if (!bitmap_is_prefix(map, test_bit))
-      goto error3;
-    bitmap_clear_all(map);
-  }
-  return FALSE;
-error1:
-  printf("prefix1 error  bitsize = %u, prefix_size = %u", bitsize,test_bit);
-  return TRUE;
-error2:
-  printf("prefix2 error  bitsize = %u, prefix_size = %u", bitsize,test_bit);
-  return TRUE;
-error3:
-  printf("prefix3 error  bitsize = %u, prefix_size = %u", bitsize,test_bit);
-  return TRUE;
-}
-
-
-bool do_test(uint bitsize)
-{
-  MY_BITMAP map;
-  my_bitmap_map buf[1024];
-  if (bitmap_init(&map, buf, bitsize, FALSE))
-  {
-    printf("init error for bitsize %d", bitsize);
-    goto error;
-  }
-  if (test_set_get_clear_bit(&map,bitsize))
-    goto error;
-  bitmap_clear_all(&map);
-  if (test_flip_bit(&map,bitsize))
-    goto error;
-  bitmap_clear_all(&map);
-  if (test_operators(&map,bitsize))
-    goto error;
-  bitmap_clear_all(&map);
-  if (test_get_all_bits(&map, bitsize))
-    goto error;
-  bitmap_clear_all(&map);
-  if (test_compare_operators(&map,bitsize))
-    goto error;
-  bitmap_clear_all(&map);
-  if (test_count_bits_set(&map,bitsize))
-    goto error;
-  bitmap_clear_all(&map);
-  if (test_get_first_bit(&map,bitsize))
-    goto error;
-  bitmap_clear_all(&map);
-  if (test_get_next_bit(&map,bitsize))
-    goto error;
-  if (test_prefix(&map,bitsize))
-    goto error;
-  return FALSE;
-error:
-  printf("\n");
-  return TRUE;
-}
-
-int main()
-{
-  int i;
-  for (i= 1; i < 4096; i++)
-  {
-    printf("Start test for bitsize=%u\n",i);
-    if (do_test(i))
-      return -1;
-  }
-  printf("OK\n");
-  return 0;
-}
-
-/*
-  In directory mysys:
-  make test_bitmap
-  will build the bitmap tests and ./test_bitmap will execute it
-*/
-
-#endif

unittest/mysys/bitmap-t.c

-/* Copyright (C) 2006 MySQL AB
+/* Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -24,6 +24,8 @@
 #include <tap.h>
 #include <m_string.h>
 
+#define MAX_TESTED_BITMAP_SIZE 1024
+
 uint get_rand_bit(uint bitsize)
 {
   return (rand() % bitsize);
@@ -75,12 +77,6 @@ my_bool test_flip_bit(MY_BITMAP *map, uint bitsize)
   return TRUE;
 }
 
-my_bool test_operators(MY_BITMAP *map __attribute__((unused)),
-                       uint bitsize __attribute__((unused)))
-{
-  return FALSE;
-}
-
 my_bool test_get_all_bits(MY_BITMAP *map, uint bitsize)
 {
   uint i;
@@ -129,8 +125,8 @@ my_bool test_compare_operators(MY_BITMAP *map, uint bitsize)
   uint no_loops= bitsize > 128 ? 128 : bitsize;
   MY_BITMAP map2_obj, map3_obj;
   MY_BITMAP *map2= &map2_obj, *map3= &map3_obj;
-  uint32 map2buf[1024];
-  uint32 map3buf[1024];
+  uint32 map2buf[MAX_TESTED_BITMAP_SIZE];
+  uint32 map3buf[MAX_TESTED_BITMAP_SIZE];
   bitmap_init(&map2_obj, map2buf, bitsize, FALSE);
   bitmap_init(&map3_obj, map3buf, bitsize, FALSE);
   bitmap_clear_all(map2);
@@ -259,6 +255,19 @@ my_bool test_get_first_bit(MY_BITMAP *map, uint bitsize)
 {
   uint i, test_bit;
   uint no_loops= bitsize > 128 ? 128 : bitsize;
+
+  bitmap_set_all(map);
+  for (i=0; i < bitsize; i++)
+    bitmap_clear_bit(map, i);
+  if (bitmap_get_first_set(map) != MY_BIT_NONE)
+    goto error1;
+  bitmap_clear_all(map);
+  for (i=0; i < bitsize; i++)
+    bitmap_set_bit(map, i);
+  if (bitmap_get_first(map) != MY_BIT_NONE)
+    goto error2;
+  bitmap_clear_all(map);
+
   for (i=0; i < no_loops; i++)
   {
     test_bit=get_rand_bit(bitsize);
@@ -321,6 +330,24 @@ my_bool test_prefix(MY_BITMAP *map, uint bitsize)
       goto error3;
     bitmap_clear_all(map);
   }
+  for (i=0; i < bitsize; i++)
+  {
+    if (bitmap_is_prefix(map, i + 1))
+      goto error4;
+    bitmap_set_bit(map, i);
+    if (!bitmap_is_prefix(map, i + 1))
+      goto error5;
+    test_bit=get_rand_bit(bitsize);
+    bitmap_set_bit(map, test_bit);
+    if (test_bit <= i && !bitmap_is_prefix(map, i + 1))
+      goto error5;
+    else if (test_bit > i)
+    {
+      if (bitmap_is_prefix(map, i + 1))
+        goto error4;
+      bitmap_clear_bit(map, test_bit);
+    }
+  }
   return FALSE;
 error1:
   diag("prefix1 error  bitsize = %u, prefix_size = %u", bitsize,test_bit);
@@ -331,13 +358,127 @@ my_bool test_prefix(MY_BITMAP *map, uint bitsize)
 error3:
   diag("prefix3 error  bitsize = %u, prefix_size = %u", bitsize,test_bit);
   return TRUE;
+error4:
+  diag("prefix4 error  bitsize = %u, i = %u", bitsize,i);
+  return TRUE;
+error5:
+  diag("prefix5 error  bitsize = %u, i = %u", bitsize,i);
+  return TRUE;
+}
+
+my_bool test_compare(MY_BITMAP *map, uint bitsize)
+{
+  MY_BITMAP map2;
+  uint32 map2buf[MAX_TESTED_BITMAP_SIZE];
+  uint i, test_bit;
+  uint no_loops= bitsize > 128 ? 128 : bitsize;
+  if (bitmap_init(&map2, map2buf, bitsize, FALSE))
+  {
+    diag("init error for bitsize %d", bitsize);
+    return TRUE;
+  }
+  /* Test all 4 possible combinations of set/unset bits. */
+  for (i=0; i < no_loops; i++)
+  {
+    test_bit=get_rand_bit(bitsize);
+    bitmap_clear_bit(map, test_bit);
+    bitmap_clear_bit(&map2, test_bit);
+    if (!bitmap_is_subset(map, &map2))
+      goto error_is_subset;
+    bitmap_set_bit(map, test_bit);
+    if (bitmap_is_subset(map, &map2))
+      goto error_is_subset;
+    bitmap_set_bit(&map2, test_bit);
+    if (!bitmap_is_subset(map, &map2))
+      goto error_is_subset;
+    bitmap_clear_bit(map, test_bit);
+    if (!bitmap_is_subset(map, &map2))
+      goto error_is_subset;
+    /* Note that test_bit is not cleared i map2. */
+  }
+  bitmap_clear_all(map);
+  bitmap_clear_all(&map2);
+  /* Test all 4 possible combinations of set/unset bits. */
+  for (i=0; i < no_loops; i++)
+  {
+    test_bit=get_rand_bit(bitsize);
+    if (bitmap_is_overlapping(map, &map2))
+      goto error_is_overlapping;
+    bitmap_set_bit(map, test_bit);
+    if (bitmap_is_overlapping(map, &map2))
+      goto error_is_overlapping;
+    bitmap_set_bit(&map2, test_bit);
+    if (!bitmap_is_overlapping(map, &map2))
+      goto error_is_overlapping;
+    bitmap_clear_bit(map, test_bit);
+    if (bitmap_is_overlapping(map, &map2))
+      goto error_is_overlapping;
+    bitmap_clear_bit(&map2, test_bit);
+    /* Note that test_bit is not cleared i map2. */
+  }
+  return FALSE;
+error_is_subset:
+  diag("is_subset error  bitsize = %u", bitsize);
+  return TRUE;
+error_is_overlapping:
+  diag("is_overlapping error  bitsize = %u", bitsize);
+  return TRUE;
 }
 
+my_bool test_intersect(MY_BITMAP *map, uint bitsize)
+{
+  uint bitsize2 = 1 + get_rand_bit(MAX_TESTED_BITMAP_SIZE - 1);
+  MY_BITMAP map2;
+  uint32 map2buf[bitsize2];
+  uint i, test_bit1, test_bit2, test_bit3;
+  if (bitmap_init(&map2, map2buf, bitsize2, FALSE))
+  {
+    diag("init error for bitsize %d", bitsize2);
+    return TRUE;
+  }
+  test_bit1= get_rand_bit(bitsize);
+  test_bit2= get_rand_bit(bitsize);
+  bitmap_set_bit(map, test_bit1);
+  bitmap_set_bit(map, test_bit2);
+  test_bit3= get_rand_bit(bitsize2);
+  bitmap_set_bit(&map2, test_bit3);
+  if (test_bit2 < bitsize2)
+    bitmap_set_bit(&map2, test_bit2);
+
+  bitmap_intersect(map, &map2);
+  if (test_bit2 < bitsize2)
+  {
+    if (!bitmap_is_set(map, test_bit2))
+      goto error;
+    bitmap_clear_bit(map, test_bit2);
+  }
+  if (test_bit1 == test_bit3)
+  {
+    if (!bitmap_is_set(map, test_bit1))
+      goto error;
+    bitmap_clear_bit(map, test_bit1);
+  }
+  if (!bitmap_is_clear_all(map))
+    goto error;
+
+  bitmap_set_all(map);
+  bitmap_set_all(&map2);
+  for (i=0; i < bitsize2; i++)
+    bitmap_clear_bit(&map2, i);
+  bitmap_intersect(map, &map2);
+  if (!bitmap_is_clear_all(map))
+    goto error;
+  return FALSE;
+error:
+  diag("intersect error  bitsize = %u, bit1 = %u, bit2 = %u, bit3 = %u",
+       bitsize, test_bit1, test_bit2, test_bit3);
+  return TRUE;
+}
 
 my_bool do_test(uint bitsize)
 {
   MY_BITMAP map;
-  uint32 buf[1024];
+  uint32 buf[MAX_TESTED_BITMAP_SIZE];
   if (bitmap_init(&map, buf, bitsize, FALSE))
   {
     diag("init error for bitsize %d", bitsize);
@@ -349,9 +490,6 @@ my_bool do_test(uint bitsize)
   if (test_flip_bit(&map,bitsize))
     goto error;
   bitmap_clear_all(&map);
-  if (test_operators(&map,bitsize))
-    goto error;
-  bitmap_clear_all(&map);
   if (test_get_all_bits(&map, bitsize))
     goto error;
   bitmap_clear_all(&map);
@@ -366,8 +504,15 @@ my_bool do_test(uint bitsize)
   bitmap_clear_all(&map);
   if (test_get_next_bit(&map,bitsize))
     goto error;
+  bitmap_clear_all(&map);
   if (test_prefix(&map,bitsize))
     goto error;
+  bitmap_clear_all(&map);
+  if (test_compare(&map,bitsize))
+    goto error;
+  bitmap_clear_all(&map);
+  if (test_intersect(&map,bitsize))
+    goto error;
   return FALSE;
 error:
   return TRUE;
@@ -377,7 +522,7 @@ int main()
 {
   int i;
   int const min_size = 1;
-  int const max_size = 1024;
+  int const max_size = MAX_TESTED_BITMAP_SIZE;
   MY_INIT("bitmap-t");
 
   plan(max_size - min_size);