X-Git-Url: http://deadsoftware.ru/gitweb?a=blobdiff_plain;f=src%2Fshared%2Fhashtable.pas;h=9f72e3ab2f5fb547da371473cc30e87e8b47887b;hb=a4f25c41dfd783a925aa2dab4b9b84753d5c3f18;hp=15d19f6a15e8d6bd296423412e1580114c9552ff;hpb=21b8c729c535950bb33c3c036f3510331462d00d;p=d2df-sdl.git

diff --git a/src/shared/hashtable.pas b/src/shared/hashtable.pas
index 15d19f6..9f72e3a 100644
--- a/src/shared/hashtable.pas
+++ b/src/shared/hashtable.pas
@@ -39,22 +39,60 @@ type
     type TEquFn = function (constref a, b: KeyT): Boolean;
     type TIteratorFn = function (constref k: KeyT; constref v: ValueT): Boolean is nested; // return `true` to stop
 
-  private
     type
       PEntry = ^TEntry;
       TEntry = record
+      public
         key: KeyT;
         value: ValueT;
+      private
         hash: LongWord; // key hash or 0
         nextFree: PEntry; // next free entry
       end;
 
+  private
+    type
+      TEntryArray = array of TEntry;
+
+      TValEnumerator = record
+      private
+        mEntries: TEntryArray;
+        mFirstEntry, mLastEntry, cur: Integer;
+      public
+        constructor Create (const aents: TEntryArray; afirst, alast: Integer);
+        function MoveNext (): Boolean; inline;
+        function getCurrent (): ValueT; inline;
+        property Current: ValueT read getCurrent;
+      end;
+
+      TKeyEnumerator = record
+      private
+        mEntries: TEntryArray;
+        mFirstEntry, mLastEntry, cur: Integer;
+      public
+        constructor Create (const aents: TEntryArray; afirst, alast: Integer);
+        function MoveNext (): Boolean; inline;
+        function getCurrent (): KeyT; inline;
+        property Current: KeyT read getCurrent;
+      end;
+
+      TKeyValEnumerator = record
+      private
+        mEntries: TEntryArray;
+        mFirstEntry, mLastEntry, cur: Integer;
+      public
+        constructor Create (const aents: TEntryArray; afirst, alast: Integer);
+        function MoveNext (): Boolean; inline;
+        function getCurrent (): PEntry; inline;
+        property Current: PEntry read getCurrent;
+      end;
+
   private
     hashfn: THashFn;
     equfn: TEquFn;
     mBuckets: array of PEntry; // entries, points to mEntries elements
     mBucketsUsed: Integer;
-    mEntries: array of TEntry;
+    mEntries: TEntryArray;
     {$IFDEF RBHASH_SANITY_CHECKS}
     mEntriesUsed: Integer;
     {$ENDIF}
@@ -77,6 +115,7 @@ type
     destructor Destroy (); override;
 
     procedure clear ();
+    procedure reset (); // don't shrink buckets
 
     procedure rehash ();
     procedure compact (); // call this instead of `rehash()` after alot of deletions
@@ -89,11 +128,16 @@ type
     //WARNING! don't modify table in iterator (queries are ok, though)
     function forEach (it: TIteratorFn): Boolean;
 
+    // default `for ... in` enums values
+    function GetEnumerator (): TValEnumerator;
+    function byKey (): TKeyEnumerator;
+    function byValue (): TValEnumerator;
+    function byKeyValue (): TKeyValEnumerator; // PEntry
+
     property count: Integer read mBucketsUsed;
     property capacity: Integer read getCapacity;
   end;
 
-
 type
   TJoaatHasher = record
   private
@@ -106,7 +150,7 @@ type
     procedure reset (); inline; overload;
     procedure reset (aseed: LongWord); inline; overload;
 
-    procedure put (const buf; len: LongWord);
+    procedure put (constref buf; len: LongWord);
 
     // current hash value
     // you can continue putting data, as this is not destructive
@@ -116,13 +160,15 @@ type
 
 type
   THashIntInt = specialize THashBase<Integer, Integer>;
+  THashStrInt = specialize THashBase<AnsiString, Integer>;
 
 function hashNewIntInt (): THashIntInt;
+function hashNewStrInt (): THashStrInt;
 
 
 function u32Hash (a: LongWord): LongWord; inline;
-function fnvHash (const buf; len: LongWord): LongWord;
-function joaatHash (const buf; len: LongWord): LongWord;
+function fnvHash (constref buf; len: LongWord): LongWord;
+function joaatHash (constref buf; len: LongWord): LongWord;
 
 function nextPOT (x: LongWord): LongWord; inline;
 
@@ -152,6 +198,7 @@ end;
 
 // ////////////////////////////////////////////////////////////////////////// //
 function hiiequ (constref a, b: Integer): Boolean; begin result := (a = b); end;
+function hsiequ (constref a, b: AnsiString): Boolean; begin result := (a = b); end;
 
 {$PUSH}
 {$RANGECHECKS OFF}
@@ -166,6 +213,11 @@ begin
   result := result xor (result shl 10);
   result := result xor (result shr 15);
 end;
+
+function hsihash (constref k: AnsiString): LongWord;
+begin
+  if (Length(k) > 0) then result := fnvHash(PAnsiChar(k)^, Length(k)) else result := 0;
+end;
 {$POP}
 
 
@@ -175,6 +227,12 @@ begin
 end;
 
 
+function hashNewStrInt (): THashStrInt;
+begin
+  result := THashStrInt.Create(hsihash, hsiequ);
+end;
+
+
 // ////////////////////////////////////////////////////////////////////////// //
 {$PUSH}
 {$RANGECHECKS OFF}
@@ -197,7 +255,7 @@ begin
 end;
 
 
-procedure TJoaatHasher.put (const buf; len: LongWord);
+procedure TJoaatHasher.put (constref buf; len: LongWord);
 var
   bytes: PByte;
   h: LongWord;
@@ -227,12 +285,12 @@ end;
 {$POP}
 
 
-function joaatHash (const buf; len: LongWord): LongWord;
+function joaatHash (constref buf; len: LongWord): LongWord;
 var
   h: TJoaatHasher;
 begin
   h := TJoaatHasher.Create(0);
-  h.put(buf, len);
+  h.put(PByte(@buf)^, len);
   result := h.value;
 end;
 
@@ -241,7 +299,7 @@ end;
 {$PUSH}
 {$RANGECHECKS OFF}
 // fnv-1a: http://www.isthe.com/chongo/tech/comp/fnv/
-function fnvHash (const buf; len: LongWord): LongWord;
+function fnvHash (constref buf; len: LongWord): LongWord;
 var
   b: PByte;
 begin
@@ -304,6 +362,7 @@ begin
   for idx := 0 to High(mBuckets) do mBuckets[idx] := nil;
 
   SetLength(mEntries, Length(mBuckets));
+  {
   for idx := 0 to High(mEntries)-1 do
   begin
     mEntries[idx].hash := 0;
@@ -311,17 +370,63 @@ begin
   end;
   mEntries[High(mEntries)].hash := 0;
   mEntries[High(mEntries)].nextFree := nil;
+  }
+  {
+  for idx := 0 to High(mEntries) do
+  begin
+    mEntries[idx].hash := 0;
+    mEntries[idx].nextFree := nil;
+  end;
+  }
 
   mBucketsUsed := 0;
   {$IFDEF RBHASH_SANITY_CHECKS}
   mEntriesUsed := 0;
   {$ENDIF}
-  mFreeEntryHead := @mEntries[0];
+  mFreeEntryHead := nil; //@mEntries[0];
   mFirstEntry := -1;
   mLastEntry := -1;
 end;
 
 
+procedure THashBase.reset ();
+var
+  idx: Integer;
+begin
+  if (mBucketsUsed > 0) then
+  begin
+    for idx := 0 to High(mBuckets) do mBuckets[idx] := nil;
+    {
+    for idx := 0 to High(mEntries)-1 do
+    begin
+      mEntries[idx].hash := 0;
+      mEntries[idx].nextFree := @mEntries[idx+1]; //idx+1;
+    end;
+    mEntries[High(mEntries)].hash := 0;
+    mEntries[High(mEntries)].nextFree := nil;
+    }
+    {
+    if (mFirstEntry >= 0) then
+    begin
+      for idx := mFirstEntry to mLastEntry do
+      begin
+        mEntries[idx].hash := 0;
+        mEntries[idx].nextFree := nil;
+      end;
+    end;
+    }
+
+    mBucketsUsed := 0;
+    {$IFDEF RBHASH_SANITY_CHECKS}
+    mEntriesUsed := 0;
+    {$ENDIF}
+    mFreeEntryHead := nil; //@mEntries[0];
+    mFirstEntry := -1;
+    mLastEntry := -1;
+  end;
+end;
+
+
 function THashBase.getCapacity (): Integer; inline; begin result := Length(mBuckets); end;
 
 
@@ -329,6 +434,22 @@ function THashBase.allocEntry (): PEntry;
 var
   idx: Integer;
 begin
+  if (mFreeEntryHead = nil) then
+  begin
+    if (mLastEntry = High(mEntries)) then raise Exception.Create('internal error in hash entry allocator (0.0)');
+    Inc(mLastEntry);
+    if (mFirstEntry = -1) then
+    begin
+      if (mLastEntry <> 0) then raise Exception.Create('internal error in hash entry allocator (0.1)');
+      mFirstEntry := 0;
+    end;
+    result := @mEntries[mLastEntry];
+    result.nextFree := nil; // just in case
+    {$IFDEF RBHASH_SANITY_CHECKS}
+    Inc(mEntriesUsed);
+    {$ENDIF}
+    exit;
+  end;
   {$IFDEF RBHASH_SANITY_CHECKS}
   if (mFreeEntryHead = nil) then raise Exception.Create('internal error in hash entry allocator (0)');
   if (mFreeEntryHead.hash <> 0) then raise Exception.Create('internal error in hash entry allocator (1)');
@@ -365,12 +486,12 @@ begin
   if (idx < 0) or (idx > High(mEntries)) then raise Exception.Create('internal error in hash entry allocator (invalid entry address)');
   if (e <> @mEntries[idx]) then raise Exception.Create('internal error in hash entry allocator (wtf?!)');
   {$ENDIF}
-  e.hash := 0;
-  e.nextFree := mFreeEntryHead;
-  mFreeEntryHead := e; //idx;
   {$IFDEF RBHASH_SANITY_CHECKS}
   Dec(mEntriesUsed);
   {$ENDIF}
+  e.hash := 0;
+  e.nextFree := mFreeEntryHead;
+  mFreeEntryHead := e; //idx;
   // fix mFirstEntry and mLastEntry
   {$IFDEF RBHASH_SANITY_CHECKS}
   if (mFirstEntry < 0) or (mLastEntry < 0) then raise Exception.Create('internal error in hash entry allocator (invalid first/last range; 0)');
@@ -797,4 +918,105 @@ begin
 end;
 
 
+// enumerators
+function THashBase.GetEnumerator (): TValEnumerator;
+begin
+  if (Length(mEntries) > 0) then result := TValEnumerator.Create(mEntries, mFirstEntry, mLastEntry)
+  else result := TValEnumerator.Create(nil, -1, -1);
+end;
+
+function THashBase.byKey (): TKeyEnumerator;
+begin
+  if (Length(mEntries) > 0) then result := TKeyEnumerator.Create(mEntries, mFirstEntry, mLastEntry)
+  else result := TKeyEnumerator.Create(nil, -1, -1);
+end;
+
+function THashBase.byValue (): TValEnumerator;
+begin
+  if (Length(mEntries) > 0) then result := TValEnumerator.Create(mEntries, mFirstEntry, mLastEntry)
+  else result := TValEnumerator.Create(nil, -1, -1);
+end;
+
+function THashBase.byKeyValue (): TKeyValEnumerator; // PEntry
+begin
+  if (Length(mEntries) > 0) then result := TKeyValEnumerator.Create(mEntries, mFirstEntry, mLastEntry)
+  else result := TKeyValEnumerator.Create(nil, -1, -1);
+end;
+
+
+// ////////////////////////////////////////////////////////////////////////// //
+constructor THashBase.TValEnumerator.Create (const aents: TEntryArray; afirst, alast: Integer);
+begin
+  mEntries := aents;
+  mFirstEntry := afirst;
+  mLastEntry := alast;
+  cur := mFirstEntry-1;
+end;
+
+function THashBase.TValEnumerator.MoveNext (): Boolean; inline;
+begin
+  Inc(cur);
+  while (cur <= mLastEntry) do
+  begin
+    if (mEntries[cur].hash <> 0) then begin result := true; exit; end;
+  end;
+  result := false;
+end;
+
+function THashBase.TValEnumerator.getCurrent (): ValueT; inline;
+begin
+  result := mEntries[cur].value;
+end;
+
+
+// ////////////////////////////////////////////////////////////////////////// //
+constructor THashBase.TKeyEnumerator.Create (const aents: TEntryArray; afirst, alast: Integer);
+begin
+  mEntries := aents;
+  mFirstEntry := afirst;
+  mLastEntry := alast;
+  cur := mFirstEntry-1;
+end;
+
+function THashBase.TKeyEnumerator.MoveNext (): Boolean; inline;
+begin
+  Inc(cur);
+  while (cur <= mLastEntry) do
+  begin
+    if (mEntries[cur].hash <> 0) then begin result := true; exit; end;
+  end;
+  result := false;
+end;
+
+function THashBase.TKeyEnumerator.getCurrent (): KeyT; inline;
+begin
+  result := mEntries[cur].key;
+end;
+
+
+// ////////////////////////////////////////////////////////////////////////// //
+constructor THashBase.TKeyValEnumerator.Create (const aents: TEntryArray; afirst, alast: Integer);
+begin
+  mEntries := aents;
+  mFirstEntry := afirst;
+  mLastEntry := alast;
+  cur := mFirstEntry-1;
+end;
+
+function THashBase.TKeyValEnumerator.MoveNext (): Boolean; inline;
+begin
+  Inc(cur);
+  while (cur <= mLastEntry) do
+  begin
+    if (mEntries[cur].hash <> 0) then begin result := true; exit; end;
+  end;
+  result := false;
+end;
+
+function THashBase.TKeyValEnumerator.getCurrent (): PEntry; inline;
+begin
+  result := @mEntries[cur];
+end;
+
+
 end.