Merge 4.0.24 compile changes into the 4.1 tree.

mysys/my_bitmap.c

@@ -16,7 +16,18 @@
 
 /*
   Handling of uchar arrays as large bitmaps.
-  We assume that the size of the used bitmap is less than ~(uint) 0
+
+  API limitations (or, rather asserted safety assumptions,
+  to encourage correct programming)
+
+    * the size of the used bitmap is less than ~(uint) 0
+    * it's a multiple of 8 (for efficiency reasons)
+    * when arguments are a bitmap and a bit number, the number
+      must be within bitmap size
+    * bitmap_set_prefix() is an exception - one can use ~0 to set all bits
+    * when both arguments are bitmaps, they must be of the same size
+    * bitmap_intersect() is an exception :)
+      (for for Bitmap::intersect(ulonglong map2buff))
 
   TODO:
   Make assembler THREAD safe versions of these using test-and-set instructions
@@ -24,60 +35,74 @@
 
 #include "mysys_priv.h"
 #include <my_bitmap.h>
-#include <assert.h>
 #include <m_string.h>
 
 static inline void bitmap_lock(MY_BITMAP* map)
 {
 #ifdef THREAD
-  if (map->thread_safe)
-    pthread_mutex_lock(&map->mutex);
+  if (map->mutex)
+    pthread_mutex_lock(map->mutex);
 #endif
 }
 
 static inline void bitmap_unlock(MY_BITMAP* map)
 {
 #ifdef THREAD
-  if (map->thread_safe)
-    pthread_mutex_unlock(&map->mutex);
+  if (map->mutex)
+    pthread_mutex_unlock(map->mutex);
 #endif
 }
 
-my_bool bitmap_init(MY_BITMAP *map, uint bitmap_size, my_bool thread_safe)
+
+my_bool bitmap_init(MY_BITMAP *map, uchar *buf, uint bitmap_size,
+		    my_bool thread_safe)
 {
-  if (!(map->bitmap=(uchar*) my_malloc((bitmap_size+7)/8,
+  DBUG_ENTER("bitmap_init");
+
+  DBUG_ASSERT((bitmap_size & 7) == 0);
+  bitmap_size/=8;
+  if (!(map->bitmap=buf) &&
+      !(map->bitmap= (uchar*) my_malloc(bitmap_size +
+					(thread_safe ?
+					 sizeof(pthread_mutex_t) : 0),
 					MYF(MY_WME | MY_ZEROFILL))))
     return 1;
-  DBUG_ASSERT(bitmap_size != ~(uint) 0);
+  map->bitmap_size=bitmap_size;
 #ifdef THREAD
-  if ((map->thread_safe = thread_safe))
-    pthread_mutex_init(&map->mutex, MY_MUTEX_INIT_FAST);
+  if (thread_safe)
+  {
+    map->mutex=(pthread_mutex_t *)(map->bitmap+bitmap_size);
+    pthread_mutex_init(map->mutex, MY_MUTEX_INIT_FAST);
+  }
+  else
+    map->mutex=0;
 #endif
-  map->bitmap_size=bitmap_size;
-  return 0;
+  DBUG_RETURN(0);
 }
 
+
 void bitmap_free(MY_BITMAP *map)
 {
+  DBUG_ENTER("bitmap_free");
   if (map->bitmap)
   {
-    my_free((char*) map->bitmap, MYF(0));
-    map->bitmap=0;
 #ifdef THREAD
-    if (map->thread_safe)
-      pthread_mutex_destroy(&map->mutex);
+    if (map->mutex)
+      pthread_mutex_destroy(map->mutex);
 #endif
+    my_free((char*) map->bitmap, MYF(0));
+    map->bitmap=0;
   }
+  DBUG_VOID_RETURN;
 }
 
+
 void bitmap_set_bit(MY_BITMAP *map, uint bitmap_bit)
 {
-  if (bitmap_bit < map->bitmap_size)
-  {
+  DBUG_ASSERT(map->bitmap && bitmap_bit < map->bitmap_size*8);
   bitmap_lock(map);
-    map->bitmap[bitmap_bit / 8] |= (1 << (bitmap_bit & 7));
+  bitmap_fast_set_bit(map, bitmap_bit);
   bitmap_unlock(map);
-  }
 }
 
 
@@ -85,9 +110,10 @@ uint bitmap_set_next(MY_BITMAP *map)
 {
   uchar *bitmap=map->bitmap;
   uint bit_found = MY_BIT_NONE;
-  uint bitmap_size=map->bitmap_size;
+  uint bitmap_size=map->bitmap_size*8;
   uint i;
 
+  DBUG_ASSERT(map->bitmap);
   bitmap_lock(map);
   for (i=0; i < bitmap_size ; i++, bitmap++)
   {
@@ -113,32 +139,191 @@ uint bitmap_set_next(MY_BITMAP *map)
 
 void bitmap_clear_bit(MY_BITMAP *map, uint bitmap_bit)
 {
-  if (bitmap_bit < map->bitmap_size)
-  {
+  DBUG_ASSERT(map->bitmap && bitmap_bit < map->bitmap_size*8);
+  bitmap_lock(map);
+  bitmap_fast_clear_bit(map, bitmap_bit);
+  bitmap_unlock(map);
+}
+
+
+void bitmap_set_prefix(MY_BITMAP *map, uint prefix_size)
+{
+  uint prefix_bytes, prefix_bits;
+
+  DBUG_ASSERT(map->bitmap &&
+	      (prefix_size <= map->bitmap_size*8 || prefix_size == (uint) ~0));
   bitmap_lock(map);
-    map->bitmap[bitmap_bit / 8] &= ~ (1 << (bitmap_bit & 7));
+  set_if_smaller(prefix_size, map->bitmap_size*8);
+  if ((prefix_bytes= prefix_size / 8))
+    memset(map->bitmap, 0xff, prefix_bytes);
+  if ((prefix_bits= prefix_size & 7))
+    map->bitmap[prefix_bytes++]= (1 << prefix_bits)-1;
+  if (prefix_bytes < map->bitmap_size)
+    bzero(map->bitmap+prefix_bytes, map->bitmap_size-prefix_bytes);
   bitmap_unlock(map);
+}
+
+
+void bitmap_clear_all(MY_BITMAP *map)
+{
+  bitmap_set_prefix(map, 0);
+}
+
+
+void bitmap_set_all(MY_BITMAP *map)
+{
+  bitmap_set_prefix(map, ~0);
+}
+
+
+my_bool bitmap_is_prefix(const MY_BITMAP *map, uint prefix_size)
+{
+  uint prefix_bits= prefix_size & 7, res= 0;
+  uchar *m= map->bitmap, *end_prefix= map->bitmap+prefix_size/8,
+        *end= map->bitmap+map->bitmap_size;
+
+  DBUG_ASSERT(map->bitmap && prefix_size <= map->bitmap_size*8);
+
+  bitmap_lock((MY_BITMAP *)map);
+  while (m < end_prefix)
+    if (*m++ != 0xff)
+      goto ret;
+
+  if (prefix_bits && *m++ != (1 << prefix_bits)-1)
+    goto ret;
+
+  while (m < end)
+    if (*m++ != 0)
+      goto ret;
+
+  res=1;
+ret:
+  bitmap_unlock((MY_BITMAP *)map);
+  return res;
+}
+
+
+my_bool bitmap_is_clear_all(const MY_BITMAP *map)
+{
+  return bitmap_is_prefix(map, 0);
+}
+
+my_bool bitmap_is_set_all(const MY_BITMAP *map)
+{
+  return bitmap_is_prefix(map, map->bitmap_size*8);
+}
+
+
+my_bool bitmap_is_set(const MY_BITMAP *map, uint bitmap_bit)
+{
+  DBUG_ASSERT(map->bitmap && bitmap_bit < map->bitmap_size*8);
+  return bitmap_fast_is_set(map, bitmap_bit);
+}
+
+
+my_bool bitmap_is_subset(const MY_BITMAP *map1, const MY_BITMAP *map2)
+{
+  uint res=0;
+  uchar *m1=map1->bitmap, *m2=map2->bitmap, *end;
+
+  DBUG_ASSERT(map1->bitmap && map2->bitmap &&
+              map1->bitmap_size==map2->bitmap_size);
+  bitmap_lock((MY_BITMAP *)map1);
+  bitmap_lock((MY_BITMAP *)map2);
+
+  end= m1+map1->bitmap_size;
+
+  while (m1 < end)
+  {
+    if ((*m1++) & ~(*m2++))
+      goto ret;
   }
+
+  res=1;
+ret:
+  bitmap_unlock((MY_BITMAP *)map2);
+  bitmap_unlock((MY_BITMAP *)map1);
+  return res;
+}
+
+
+my_bool bitmap_cmp(const MY_BITMAP *map1, const MY_BITMAP *map2)
+{
+  uint res;
+
+  DBUG_ASSERT(map1->bitmap && map2->bitmap &&
+              map1->bitmap_size==map2->bitmap_size);
+  bitmap_lock((MY_BITMAP *)map1);
+  bitmap_lock((MY_BITMAP *)map2);
+
+  res= memcmp(map1->bitmap, map2->bitmap, map1->bitmap_size)==0;
+
+  bitmap_unlock((MY_BITMAP *)map2);
+  bitmap_unlock((MY_BITMAP *)map1);
+  return res;
 }
 
 
-void bitmap_set_all(MY_BITMAP* map)
+void bitmap_intersect(MY_BITMAP *map, const MY_BITMAP *map2)
 {
+  uchar *to=map->bitmap, *from=map2->bitmap, *end;
+  uint len=map->bitmap_size, len2=map2->bitmap_size;
+
+  DBUG_ASSERT(map->bitmap && map2->bitmap);
   bitmap_lock(map);
-  memset(map->bitmap, 0xff, (map->bitmap_size+7)/8);
+  bitmap_lock((MY_BITMAP *)map2);
+
+  end= to+min(len,len2);
+
+  while (to < end)
+    *to++ &= *from++;
+
+  if (len2 < len)
+  {
+    end+=len-len2;
+    while (to < end)
+      *to++=0;
+  }
+
+  bitmap_unlock((MY_BITMAP *)map2);
   bitmap_unlock(map);
 }
 
-my_bool bitmap_is_set(MY_BITMAP* map, uint bitmap_bit)
+
+void bitmap_subtract(MY_BITMAP *map, const MY_BITMAP *map2)
 {
-  return (bitmap_bit < map->bitmap_size) ?
-    (map->bitmap[bitmap_bit / 8] & (1 << (bitmap_bit & 7))) :
-    0;
+  uchar *to=map->bitmap, *from=map2->bitmap, *end;
+
+  DBUG_ASSERT(map->bitmap && map2->bitmap &&
+              map->bitmap_size==map2->bitmap_size);
+  bitmap_lock(map);
+  bitmap_lock((MY_BITMAP *)map2);
+
+  end= to+map->bitmap_size;
+
+  while (to < end)
+    *to++ &= ~(*from++);
+
+  bitmap_unlock((MY_BITMAP *)map2);
+  bitmap_unlock(map);
 }
 
-void bitmap_clear_all(MY_BITMAP* map)
+
+void bitmap_union(MY_BITMAP *map, const MY_BITMAP *map2)
 {
+  uchar *to=map->bitmap, *from=map2->bitmap, *end;
+
+  DBUG_ASSERT(map->bitmap && map2->bitmap &&
+              map->bitmap_size==map2->bitmap_size);
   bitmap_lock(map);
-  bzero(map->bitmap,(map->bitmap_size+7)/8);
+  bitmap_lock((MY_BITMAP *)map2);
+
+  end= to+map->bitmap_size;
+
+  while (to < end)
+    *to++ |= *from++;
+
+  bitmap_unlock((MY_BITMAP *)map2);
   bitmap_unlock(map);
 }
+