+#include <string.h>
+#include <math.h>
#include <stdlib.h>
#include "vector.h"
* void*, and an index is "unsigned long" (64 bits).
*/
-#if VECTOR_LEVEL_BITS == 4
-typedef union {
- vector_index as_whole;
- struct {
- unsigned int msb:4; unsigned int lsb:4;
- } __attribute__ ((__packed__)) as_byte[8];
-} vector_indexing;
+/** ============================================================ **/
+
+static int VECTOR_BITS[4] = { 8, 4, 2, 64 };
+
+typedef struct {
+ unsigned int a:2;
+ unsigned int b:2;
+ unsigned int c:2;
+ unsigned int d:2;
+} bitpair;
-#define VECTOR_LEVEL_MASK ( VECTOR_SLOTS - 1 )
+typedef struct {
+ unsigned int a:4;
+ unsigned int b:4;
+} nibble;
-#define VECTOR_PART_BYTE(i,p) ((vector_indexing*)(i))->as_byte[ (p)/2 ]
+typedef struct {
+ unsigned int a:8;
+} byte;
-static int VECTOR_INDEX_PART(vector_index *index,int part) {
- if ( part & 1 ) {
- return VECTOR_PART_BYTE(index,part).lsb;
+/**
+ * Return the index part for the given level of the vector's leveling
+ * variant.
+ *
+ * The vector variant indicates whether indexing uses 8, 4, or 2 bits
+ * per level.
+ */
+unsigned long VECTOR_INDEX_PART(vector *pv,vector_index *index, int level) {
+ unsigned char *px = (unsigned char *) index;
+ switch ( pv->variant ) {
+ case byte_index_levels: {
+ byte *pp = (byte*)(px + level);
+ return pp->a;
+ }
+ case nibble_index_levels: {
+ nibble *pp = (nibble*)( px + ( level / 2 ) );
+ switch ( level & 1 ) {
+ case 0: return pp->a;
+ case 1: return pp->b;
+ }
+ break;
+ }
+ case bitpair_index_levels: {
+ bitpair *pp = (bitpair*)( px + ( level / 4 ) );
+ switch ( level & 3 ) {
+ case 0: return pp->a;
+ case 1: return pp->b;
+ case 2: return pp->c;
+ case 3: return pp->d;
+ }
+ break;
}
- return VECTOR_PART_BYTE(index,part).msb;
+ case single_index_level:
+ return (*index);
+ }
+ return 0;
}
-static int VECTOR_INDEX_PART_INC(vector_index *index,int part) {
- if ( part & 1 ) {
- return ++VECTOR_PART_BYTE(index,part).lsb;
+/**
+ * Increment the index part at the indivated level, cyclic but not
+ * carrying over to the upper level. Returns the new level index.
+ */
+static unsigned long VECTOR_INDEX_PART_INC(
+ vector *pv,vector_index *index, int level)
+{
+ unsigned char *px = (unsigned char *) index;
+ switch ( pv->variant ) {
+ case byte_index_levels: {
+ byte *pp = (byte*)( px + level );
+ return ++(pp->a);
+ }
+ case nibble_index_levels: {
+ nibble *pp = (nibble*)( px + ( level / 2 ) );
+ switch ( level & 1 ) {
+ case 0: return ++(pp->a);
+ case 1: return ++(pp->b);
+ }
+ break;
+ }
+ case bitpair_index_levels: {
+ bitpair *pp = (bitpair*)( px + level / 4 );
+ switch ( level & 3 ) {
+ case 0: return ++(pp->a);
+ case 1: return ++(pp->b);
+ case 2: return ++(pp->c);
+ case 3: return ++(pp->d);
+ }
+ break;
}
- return ++VECTOR_PART_BYTE(index,part).msb;
+ case single_index_level:
+ return ++(*index);
+ }
+ return 0;
}
-#elif VECTOR_LEVEL_BITS == 8
-#define VECTOR_LEVEL_MASK ( VECTOR_SLOTS - 1 )
+/**
+ * Decrement the index part at the indicated level, cyclic but not
+ * carrying over to the upper level. Returns the prior level index.
+ */
+static unsigned long VECTOR_INDEX_PART_DEC(
+ vector *pv,vector_index *index, int level)
+{
+ unsigned char *px = (unsigned char *) index;
+ switch ( pv->variant ) {
+ case byte_index_levels: {
+ byte *pp = (byte*)( px + level );
+ return (pp->a)--;
+ }
+ case nibble_index_levels: {
+ nibble *pp = (nibble*)( px + ( level / 2 ) );
+ switch ( level & 1 ) {
+ case 0: return (pp->a)--;
+ case 1: return (pp->b)--;
+ }
+ break;
+ }
+ case bitpair_index_levels: {
+ bitpair *pp = (bitpair*)( px + level / 4 );
+ switch ( level & 0xf ) {
+ case 0: return (pp->a)--;
+ case 1: return (pp->b)--;
+ case 2: return (pp->c)--;
+ case 3: return (pp->d)--;
+ }
+ break;
+ }
+ case single_index_level:
+ return (*index)--;
+ }
+ return 0;
+}
-typedef union {
- vector_index as_whole;
- unsigned char as_byte[8];
-} vector_indexing;
+#define ONES (~((vector_index) 0))
-#define VECTOR_INDEX_PART(i,p) (((vector_indexing*)(i))->as_byte[p])
+// Set index to first value for all index parts at level and lower.
+static void VECTOR_INDEX_FIRST(vector *pv,vector_index *index, int level) {
+ (*index) &= ONES << ( VECTOR_BITS[ pv->variant ] * level );
+}
-#define VECTOR_INDEX_PART_INC(i,p) (++VECTOR_INDEX_PART(i,p))
+// Set index to last value for all index parts at level and lower.
+static void VECTOR_INDEX_LAST(vector *pv,vector_index *index, int level) {
+ static unsigned long ones[] = { 255, 15, 3 };
+ unsigned long x = ones[ pv->variant ];
+ while ( level-- ) {
+ (*index) |= x;
+ x <<= VECTOR_BITS[ pv->variant ];
+ }
+ // 255, 25, 3
+ //(*index) |= ONES >> ( 64 - ( VECTOR_BITS[ pv->variant ] * level ) );
+}
-#endif
+// Return number of slots for a vector variant.
+unsigned long VECTOR_SLOTS(vector *pv) {
+ switch ( pv->variant ) {
+ case byte_index_levels: return 256;
+ case nibble_index_levels: return 16;
+ case bitpair_index_levels: return 4;
+ case single_index_level: return pv->size;
+ }
+ return 0;
+}
+
+// The number of levels to span vector pv wrt its size and variant
+static unsigned int vector_levels(vector *pv,unsigned int size) {
+ if ( size < 4 ) {
+ return 1;
+ }
+ switch ( pv->variant ) {
+ case byte_index_levels: return ((int)(log2( size - 1 ) / 8)) + 1;
+ case nibble_index_levels: return ((int)(log2( size - 1 ) / 4)) + 1;
+ case bitpair_index_levels: return ((int)(log2( size - 1 ) / 2)) + 1;
+ case single_index_level: return 1;
+ }
+ return 0;
+}
+
+/** ============================================================ **/
/**
* Advances a vector index to the next used slot at or below the
* update the index slots accordingly. The given index is advanced
* cyclically to match the found slot. The function returns a slot
* pointer to the used slot, if any, and 0 otherwise.
+ * The last parameter is a flag that gets set when the scanning is
+ * partial (i.e. not the whole index page).
*/
static void **vector_level_next_used(
- vector_page *page,vector_index *index,int level,vector_index end) {
- void **p = (void**)&(*page)[ VECTOR_INDEX_PART( index, level ) ];
- for( ; *index < end; p++ ) {
+ vector *pv,
+ vector_page *page,
+ vector_index *index,
+ int level,
+ int *partial )
+{
+ void **p = (void**)&(*page)[ VECTOR_INDEX_PART( pv, index, level ) ];
+ if ( VECTOR_INDEX_PART( pv, index, level ) != 0 ) {
+ *partial = 1;
+ }
+ for( ; *index < pv->size; p++ ) {
if ( *p ) {
if ( level == 0 ) {
return p; // This is a used entry
}
// *p is an index that needs to be inspected recursively
- int whole = VECTOR_INDEX_PART( index, level - 1 ) == 0;
- void **x = vector_level_next_used( *p, index, level - 1, end );
+ int w = 0;
+ void **x = vector_level_next_used( pv, *p, index, level - 1, &w );
if ( x ) {
return x; // Used slot was found; return it.
}
- // The page *p is all empty, so can/should be reclaimed.
- if ( whole ) {
+ // If the page *p is all empty, so can/should be reclaimed.
+ if ( w == 0 ) {
free( *p );
*p = 0;
+ } else {
+ *partial = 1;
+ }
+ } else {
+ if ( level > 0 ) {
+ VECTOR_INDEX_FIRST( pv, index, level - 1 );
}
}
- if ( VECTOR_INDEX_PART_INC( index, level ) == 0 ) {
+ if ( VECTOR_INDEX_PART_INC( pv, index, level ) == 0 ) {
break; // cycling this level => nothing found
}
}
return 0;
}
-// The least number of levels to span index S (typically the size of a
-// vector)
-static unsigned int vector_levels(vector_index S) {
- unsigned int N = 0;
- do {
- N++;
- S /= VECTOR_SLOTS;
- } while ( S );
- return N;
-}
-
// Find the next used slot at given index or later. Returns pointer to
-// the slot.
-void **vector_next_used(
- vector *pv,vector_index *index,
- int (*reclaim)(vector *pv,vector_index index,void *item,void *data),
- void *data )
-{
- if ( pv->entries == 0 ) {
+// the slot. This allows for a reclaim function that may reclaim slot
+// items on the way to next used slot.
+void **vector_next_used(vector *pv,vector_index *index) {
+ if ( pv->entries == 0 || *index >= pv->size ) {
*index = pv->size;
return 0;
}
- int levels = vector_levels( pv->size );
- for ( ; *index < pv->size; (*index)++ ) {
+ int levels = vector_levels( pv, pv->size );
+ int partial = 0;
+ do {
void **slot = vector_level_next_used(
- pv->entries, index, levels - 1, pv->size ) ;
+ pv, pv->entries, index, levels - 1, &partial ) ;
if ( slot == 0 ) {
- // reached the end of the vector
- *index = pv->size;
- break;
+ break; // reached the end of the vector
}
if ( *slot ) {
- // Try reclaiming the slot,
- if ( reclaim && reclaim( pv, *index, *slot, data ) == 0 ) {
- *slot = 0;
+ return slot;
+ }
+ } while ( ++(*index) < pv->size );
+ if ( partial == 0 ) {
+ free( pv->entries );
+ pv->entries = 0;
+ }
+ *index = pv->size; // reached the end of the vector
+ return 0;
+}
+
+/**
+ * Advances a vector index to the prior used slot at or below the
+ * given level, starting from the indexed entry (inclusive) and down.
+ * The function will free any empty pages it discovers, and then
+ * update the index slots accordingly. The given index is advanced
+ * cyclically to match the found slot. The function returns a slot
+ * pointer to the used slot, if any, and 0 otherwise.
+ * The last parameter is a flag that gets set when the scanning is
+ * partial (i.e. not the whole index page).
+ */
+static void **vector_level_prev_used(
+ vector *pv,
+ vector_page *page,
+ vector_index *index,
+ int level,
+ int *partial )
+{
+ void **p = (void**)&(*page)[ VECTOR_INDEX_PART( pv, index, level ) ];
+ if ( VECTOR_INDEX_PART( pv, index, level ) != VECTOR_SLOTS( pv ) - 1 ) {
+ *partial = 1;
+ }
+ do {
+ if ( *p ) {
+ if ( level == 0 ) {
+ return p; // This is a used entry
+ }
+ // *p is an index that needs to be inspected recursively
+ int w = 0;
+ void **x = vector_level_prev_used( pv, *p, index, level - 1, &w );
+ if ( x ) {
+ return x; // Used slot was found; return it.
+ }
+ // If the page *p is all empty, it can/should be reclaimed.
+ if ( w == 0 ) {
+ free( *p );
+ *p = 0;
} else {
- return slot;
+ *partial = 1;
+ }
+ } else {
+ if ( level > 0 ) {
+ VECTOR_INDEX_LAST( pv, index, level );
}
}
+ p--;
+ } while ( VECTOR_INDEX_PART_DEC( pv, index, level ) != 0 );
+ return 0;
+}
+
+// Find the next used slot at given index or later. Returns pointer to
+// the slot. This allows for a reclaim function that may reclaim slot
+// items on the way to next used slot.
+void **vector_prev_used(vector *pv,vector_index *index) {
+ if ( pv->entries == 0 || *index >= pv->size ) {
+ *index = pv->size;
+ return 0;
}
+ int levels = vector_levels( pv, pv->size );
+ int partial = 0;
+ do {
+ void **slot = vector_level_prev_used(
+ pv, pv->entries, index, levels - 1, &partial ) ;
+ if ( slot == 0 ) {
+ break; // reached the end of the vector
+ }
+ if ( *slot ) {
+ return slot;
+ }
+ } while ( (*index)-- != 0 );
+ if ( partial == 0 ) {
+ free( pv->entries );
+ pv->entries = 0;
+ }
+ *index = pv->size; // reached the end of the vector
return 0;
}
-// Reclaim tree of unused pages
-static void vector_reclaim(vector_page *page,unsigned int level) {
+// Reclaim tree of unused pages for a given level
+static void vector_reclaim(vector *pv,vector_page *page,unsigned int level) {
int i = 0;
if ( level > 0 ) {
- for ( ; i < VECTOR_SLOTS; i++ ) {
+ for ( ; i < VECTOR_SLOTS( pv ); i++ ) {
if ( (*page)[i] ) {
- vector_reclaim( (vector_page *) (*page)[i], level - 1 );
+ vector_reclaim( pv, (vector_page *) (*page)[i], level - 1 );
}
}
}
}
// Resize vector, using the reclaim function as needed, to handle any
-// excess items or to veto the resize. Returns the index of the veto, if
-// any, or <0 otherwise, with -1 indicating success and -2 indicating
-// OOM while growing.
+// excess items or to veto the resize. Returns the index of the veto,
+// if any, or <0 otherwise, with -1 indicating success and -2
+// indicating OOM
//
-// Nothe that resizing may result in the introduction/removal of
+// Note that resizing may result in the introduction/removal of
// indexing levels and pages, so as to keep the leveling accurate for
// the size.
int vector_resize(
int (*reclaim)(vector *pv,vector_index index,void *item,void *data),
void *data )
{
- // Table of number of slots for a level above that of the number
- // at the prior lower level. The first level (i.e., level 0) adds
- // 15 slots to the one slot of no index page. Level 1 adds 15*16
- // slots, level 2 adds 15*(16^2), and generically level i adds
- // 15*(16^i) slots.
- static int level_delta[ VECTOR_INDEX_FIELDS ];
- if ( level_delta[ 0 ] == 0 ) {
- int d = 1;
- int i;
- for ( i = 0; i < VECTOR_INDEX_FIELDS; i++ ) {
- level_delta[ i ] = ( VECTOR_SLOTS - 1 ) * d;
- d = VECTOR_SLOTS * d;
- }
- }
struct {
int old;
int new;
} level = {
- vector_levels( pv->size ),
- vector_levels( new_size )
+ vector_levels( pv, pv->size ),
+ vector_levels( pv, new_size )
};
+ vector_page *entries = 0;
if ( pv->entries == 0 ) {
pv->size = new_size;
return 0;
// A shrinking vector might be veto-ed
if ( new_size < pv->size ) {
vector_index index = new_size;
- void **slot = vector_next_used( pv, &index, reclaim, data );
- if ( slot ) {
+ void **slot = vector_next_used( pv, &index );
+ while ( slot ) {
+ if ( *slot && reclaim && reclaim( pv, index, *slot, data ) == 0 ) {
+ *slot = 0;
+ slot = vector_next_used( pv, &index );
+ continue;
+ }
return index;
}
// At this point we know that there are no slots used after
// the new_size size, so now it's time to remove and reclaim
// any superflouous top level pages.
- vector_page *entries;
- vector_page **pp = &pv->entries;
- while ( level.old-- > level.new ) {
- if ( pp ) {
- pp = (vector_page **)(*pp)[0];
+ if ( pv->variant == single_index_level ) {
+ // Follow vector size using realloc
+ if ( new_size > 0 ) {
+ entries = (vector_page*)
+ realloc( pv->entries, new_size * sizeof( void* ) );
+ if ( entries == 0 ) {
+ return -2; // OOM
+ }
}
- }
- if ( pp != &pv->entries ) {
- entries = pv->entries;
- if ( pp ) {
- pv->entries = *pp;
- *pp = 0; // Detach subtree
- } else {
+ pv->entries = entries;
+ } else {
+ vector_page **pp = &pv->entries;
+ int i = level.old;
+ while ( i-- > level.new ) {
+ if ( pp ) {
+ pp = (vector_page **)(*pp);
+ }
+ }
+ if ( pp != &pv->entries ) {
+ entries = pv->entries;
+ if ( pp ) {
+ pv->entries = *pp;
+ *pp = 0; // Detach subtree
+ } else {
+ pv->entries = 0;
+ }
+ vector_reclaim( pv, entries, level.old - 1 );
+ }
+ if ( new_size == 0 && pv->entries ) {
+ free( pv->entries );
pv->entries = 0;
}
- vector_reclaim( entries, level.old );
- }
- if ( new_size == 0 && pv->entries ) {
- free( pv->entries );
- pv->entries = 0;
}
} else {
// vector is growing. Maybe insert levels.
- while ( level.old < level.new ) {
- vector_page *p = (vector_page *)
- calloc( 1, sizeof( vector_page ) );
- if ( p == 0 ) {
+ if ( pv->variant == single_index_level ) {
+ // Follow vector size using realloc
+ entries = (vector_page *)realloc(
+ pv->entries, new_size * sizeof( void* ) );
+ if ( entries == 0 ) {
return -2; // OOM
}
- (*p)[0] = pv->entries;
- pv->entries = p;
- pv->size += level_delta[ level.old++ ];
- // Note that the last level addition might make the size
- // larger than requested, which gets corrected below.
+ pv->entries = entries;
+ memset( &(*entries)[ pv->size ], 0,
+ ( new_size - pv->size ) * sizeof( void* ) );
+ } else {
+ for ( ; level.old < level.new; level.old++ ) {
+ vector_page *p = (vector_page *)
+ calloc( VECTOR_SLOTS( pv ), sizeof( void* ) );
+ if ( p == 0 ) {
+ return -2; // OOM
+ }
+ (*p)[0] = pv->entries;
+ pv->entries = p;
+ // Should maybe change the size to match the level?
+ // otherwise recovery from OOM is impossible
+ }
}
}
pv->size = new_size;
return -1;
}
-// Return a pointer to the indexed item the given page level, adding
-// intermediate pages if requested. Returns 0 if addition fails (OOM),
-// or if not requested and page is missing.
-// Level 0 = pointer to the item entry itself.
-// Level VECTORLEVELS( pv->size ) - 1 =
-static void **vector_access(
- vector *pv,vector_index index,int level,int add)
-{
+// Return pointer to the indexed page slot at the requested level, and
+// adding intermediate index pages if so requested. Returns 0 if
+// addition fails (OOM), or if not requested and page is missing.
+void **vector_access(vector *pv,vector_index index,int level,int add) {
if ( index >= pv->size ) {
return 0;
}
void **page = (void**) &pv->entries;
- int i = vector_levels( pv->size );
+ int i = vector_levels( pv, pv->size );
while ( i-- > level ) {
if ( add && (*page) == 0 ) {
- (*page) = calloc( VECTOR_SLOTS, sizeof( void* ) );
+ (*page) = calloc( VECTOR_SLOTS( pv ), sizeof( void* ) );
}
page = (*page);
if ( page == 0 ) {
return 0;
}
- page += VECTOR_INDEX_PART( &index, i );
+ page += VECTOR_INDEX_PART( pv, &index, i );
}
return page;
}
*p = value;
}
+// Set value at index but return the old value
+void *vector_get_set(vector *pv,vector_index index,void *value) {
+ void **p = vector_entry( pv, index );
+ void *old = *p;
+ *p = value;
+ return old;
+}
+
inline void *vector_get(vector *pv,vector_index index) {
- return *(vector_entry( pv, index ));
+ void **p = vector_entry( pv, index );
+ return *p;
}
int vector_reclaim_any(vector *pv,vector_index ix,void *item,void *data) {
}
}
+vector *vector_clone(enum vector_variant variant,vector *src) {
+ vector *dst = (vector*) malloc( sizeof( vector ) );
+ (*dst) = (vector) { .variant = variant, .size = 0, .entries = 0 };
+ vector_resize( dst, src->size, 0, 0 );
+ vector_copy( dst, 0, src, 0, src->size );
+ return dst;
+}
+
void vector_dump(vector *pv,
- int (*itemdump)(const vector_index,const void *)) {
+ void (*itemdump)(const vector_index,const void *)) {
vector_index index = 0;
for ( ; index < pv->size; index++ ) {
- void **slot = vector_next_used( pv, &index, 0, 0 );
+ void **slot = vector_next_used( pv, &index );
if ( slot == 0 ) {
break;
}
//// Quicksort
// Returns 1 for "in order", 0 for equal, and -1 for "wrong order"
-typedef int (*comparfn)(const void *,const void *);
+ typedef int (*comparfn)(const void *,const void *);
static void vector_qsort_part(
vector *pv,comparfn compar,
}
void vector_iterate(vector *pv,
- int (*itemfn)(vector_index,void*,void*),
- void *data )
+ vector_index start,
+ int (*itemfn)(vector_index,void*,void*),
+ void *data )
{
- vector_index index = 0;
+ vector_index index = start;
while ( index < pv->size ) {
- void **slot = vector_next_used( pv, &index, 0, 0 );
- if ( slot == 0 ) {
- break;
- }
- int i = index & VECTOR_LEVEL_MASK ;
- for ( ; i < VECTOR_SLOTS && index < pv->size; i++, index++, slot++ ) {
- if ( itemfn( index, *slot, data ) ) {
+ int end = VECTOR_SLOTS( pv );
+ int i = index & ( end - 1 );
+ for ( ; i < end && index < pv->size; i++, index++ ) {
+ void **slot = vector_access( pv, index, 0, 0 );
+ if ( itemfn( index, slot? *slot: 0, data ) ) {
return;
}
}
}
}
+
+struct find_data {
+ void *value;
+ vector_index index;
+};
+
+static int vector_find_item(vector_index index, void *item,void *data) {
+ struct find_data *fd = (struct find_data*)data;
+ if ( fd->value != item ) {
+ return 0;
+ }
+ fd->index = index;
+ return 1;
+}
+
+vector_index vector_find(vector *pv,void *value) {
+ struct find_data fd = {
+ .value = value,
+ .index = pv->size
+ };
+ vector_iterate( pv, 0, vector_find_item, &fd );
+ return fd.index;
+}
+
+// Find surrounding indexes for a given item key in a sparse vector
+void *vector_bsearch(vector *pv,vector_index *index,const void *key,
+ int (*compare)(const void *key, const void *item)) {
+ vector_index lo = 0;
+ vector_index hi = pv->size;
+ if ( hi-- == 0 || vector_prev_used( pv, &hi ) == 0 ) {
+ return 0;
+ }
+ hi++;
+ while ( lo < hi ) {
+ vector_index m = lo + ( hi - lo ) / 2;
+ void **slot = vector_next_used( pv, &m );
+ int c = compare( key, *slot );
+ if ( c == 0 ) {
+ *index = m;
+ return *slot;
+ }
+ if ( c < 0 ) {
+ hi = m;
+ } else {
+ lo = m + 1;
+ }
+ }
+ return 0;
+}
+
+// Iterator callback.
+static int checkunused(vector_index index,void *item,void *data) {
+ vector_index *last = (vector_index*) data;
+ if ( item == 0 ) {
+ (*last) = index;
+ return 1;
+ }
+ if ( *last > index ) {
+ // Only on the first iteration, with *last = vector_sie
+ if ( index == 0 ) {
+ (*last) = 1;
+ return 0;
+ }
+ *last = 0;
+ } else if ( index == (*last) ) {
+ (*last)++;
+ return 0;
+ }
+ return 1;
+}
+
+// Scan forward for the next unused vector slot
+vector_index vector_next_unused(vector *pv,vector_index index) {
+ vector_index unused = vector_size( pv );
+ vector_iterate( pv, index, checkunused, &unused );
+ return unused;
+}
projects / rrq / rrqmisc.git / blobdiff