Milestone 5: deliver embedded RDP sessions and lifecycle hardening

third_party/FreeRDP/winpr/libwinpr/utils/collections/HashTable.c

@@ -0,0 +1,873 @@
+/**
+ * WinPR: Windows Portable Runtime
+ * System.Collections.Hashtable
+ *
+ * Copyright 2014 Marc-Andre Moreau <marcandre.moreau@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <winpr/config.h>
+
+#include <winpr/crt.h>
+#include <winpr/assert.h>
+
+#include <winpr/collections.h>
+
+/**
+ * This implementation is based on the public domain
+ * hash table implementation made by Keith Pomakis:
+ *
+ * http://www.pomakis.com/hashtable/hashtable.c
+ * http://www.pomakis.com/hashtable/hashtable.h
+ */
+
+typedef struct s_wKeyValuePair wKeyValuePair;
+
+struct s_wKeyValuePair
+{
+	void* key;
+	void* value;
+
+	wKeyValuePair* next;
+	BOOL markedForRemove;
+};
+
+struct s_wHashTable
+{
+	BOOL synchronized;
+	CRITICAL_SECTION lock;
+
+	size_t numOfBuckets;
+	size_t numOfElements;
+	float idealRatio;
+	float lowerRehashThreshold;
+	float upperRehashThreshold;
+	wKeyValuePair** bucketArray;
+
+	HASH_TABLE_HASH_FN hash;
+	wObject key;
+	wObject value;
+
+	DWORD foreachRecursionLevel;
+	DWORD pendingRemoves;
+};
+
+BOOL HashTable_PointerCompare(const void* pointer1, const void* pointer2)
+{
+	return (pointer1 == pointer2);
+}
+
+UINT32 HashTable_PointerHash(const void* pointer)
+{
+	return ((UINT32)(UINT_PTR)pointer) >> 4;
+}
+
+BOOL HashTable_StringCompare(const void* string1, const void* string2)
+{
+	if (!string1 || !string2)
+		return (string1 == string2);
+
+	return (strcmp((const char*)string1, (const char*)string2) == 0);
+}
+
+UINT32 HashTable_StringHash(const void* key)
+{
+	UINT32 c = 0;
+	UINT32 hash = 5381;
+	const BYTE* str = (const BYTE*)key;
+
+	/* djb2 algorithm */
+	while ((c = *str++) != '\0')
+		hash = (hash * 33) + c;
+
+	return hash;
+}
+
+void* HashTable_StringClone(const void* str)
+{
+	return winpr_ObjectStringClone(str);
+}
+
+void HashTable_StringFree(void* str)
+{
+	winpr_ObjectStringFree(str);
+}
+
+static inline BOOL HashTable_IsProbablePrime(size_t oddNumber)
+{
+	for (size_t i = 3; i < 51; i += 2)
+	{
+		if (oddNumber == i)
+			return TRUE;
+		else if (oddNumber % i == 0)
+			return FALSE;
+	}
+
+	return TRUE; /* maybe */
+}
+
+static inline size_t HashTable_CalculateIdealNumOfBuckets(wHashTable* table)
+{
+	WINPR_ASSERT(table);
+
+	const float numOfElements = (float)table->numOfElements;
+	const float tmp = (numOfElements / table->idealRatio);
+	size_t idealNumOfBuckets = (size_t)tmp;
+
+	if (idealNumOfBuckets < 5)
+		idealNumOfBuckets = 5;
+	else
+		idealNumOfBuckets |= 0x01;
+
+	while (!HashTable_IsProbablePrime(idealNumOfBuckets))
+		idealNumOfBuckets += 2;
+
+	return idealNumOfBuckets;
+}
+
+static inline void HashTable_Rehash(wHashTable* table, size_t numOfBuckets)
+{
+	UINT32 hashValue = 0;
+	wKeyValuePair* nextPair = nullptr;
+	wKeyValuePair** newBucketArray = nullptr;
+
+	WINPR_ASSERT(table);
+	if (numOfBuckets == 0)
+		numOfBuckets = HashTable_CalculateIdealNumOfBuckets(table);
+
+	if (numOfBuckets == table->numOfBuckets)
+		return; /* already the right size! */
+
+	newBucketArray = (wKeyValuePair**)calloc(numOfBuckets, sizeof(wKeyValuePair*));
+
+	if (!newBucketArray)
+	{
+		/*
+		 * Couldn't allocate memory for the new array.
+		 * This isn't a fatal error; we just can't perform the rehash.
+		 */
+		return;
+	}
+
+	for (size_t index = 0; index < table->numOfBuckets; index++)
+	{
+		wKeyValuePair* pair = table->bucketArray[index];
+
+		while (pair)
+		{
+			nextPair = pair->next;
+			hashValue = table->hash(pair->key) % numOfBuckets;
+			pair->next = newBucketArray[hashValue];
+			newBucketArray[hashValue] = pair;
+			pair = nextPair;
+		}
+	}
+
+	free((void*)table->bucketArray);
+	table->bucketArray = newBucketArray;
+	table->numOfBuckets = numOfBuckets;
+}
+
+static inline BOOL HashTable_Equals(wHashTable* table, const wKeyValuePair* pair, const void* key)
+{
+	WINPR_ASSERT(table);
+	WINPR_ASSERT(pair);
+	WINPR_ASSERT(key);
+	return table->key.fnObjectEquals(key, pair->key);
+}
+
+static inline wKeyValuePair* HashTable_Get(wHashTable* table, const void* key)
+{
+	UINT32 hashValue = 0;
+	wKeyValuePair* pair = nullptr;
+
+	WINPR_ASSERT(table);
+	if (!key)
+		return nullptr;
+
+	hashValue = table->hash(key) % table->numOfBuckets;
+	pair = table->bucketArray[hashValue];
+
+	while (pair && !HashTable_Equals(table, pair, key))
+		pair = pair->next;
+
+	return pair;
+}
+
+static inline void disposeKey(wHashTable* table, void* key)
+{
+	WINPR_ASSERT(table);
+	if (table->key.fnObjectFree)
+		table->key.fnObjectFree(key);
+}
+
+static inline void disposeValue(wHashTable* table, void* value)
+{
+	WINPR_ASSERT(table);
+	if (table->value.fnObjectFree)
+		table->value.fnObjectFree(value);
+}
+
+static inline void disposePair(wHashTable* table, wKeyValuePair* pair)
+{
+	WINPR_ASSERT(table);
+	if (!pair)
+		return;
+	disposeKey(table, pair->key);
+	disposeValue(table, pair->value);
+	free(pair);
+}
+
+static inline void setKey(wHashTable* table, wKeyValuePair* pair, const void* key)
+{
+	WINPR_ASSERT(table);
+	if (!pair)
+		return;
+	disposeKey(table, pair->key);
+	if (table->key.fnObjectNew)
+		pair->key = table->key.fnObjectNew(key);
+	else
+	{
+		union
+		{
+			const void* cpv;
+			void* pv;
+		} cnv;
+		cnv.cpv = key;
+		pair->key = cnv.pv;
+	}
+}
+
+static inline void setValue(wHashTable* table, wKeyValuePair* pair, const void* value)
+{
+	WINPR_ASSERT(table);
+	if (!pair)
+		return;
+	disposeValue(table, pair->value);
+	if (table->value.fnObjectNew)
+		pair->value = table->value.fnObjectNew(value);
+	else
+	{
+		union
+		{
+			const void* cpv;
+			void* pv;
+		} cnv;
+		cnv.cpv = value;
+		pair->value = cnv.pv;
+	}
+}
+
+/**
+ * C equivalent of the C# Hashtable Class:
+ * http://msdn.microsoft.com/en-us/library/system.collections.hashtable.aspx
+ */
+
+/**
+ * Properties
+ */
+
+/**
+ * Gets the number of key/value pairs contained in the HashTable.
+ */
+
+size_t HashTable_Count(wHashTable* table)
+{
+	WINPR_ASSERT(table);
+	return table->numOfElements;
+}
+
+/**
+ * Methods
+ */
+
+/**
+ * Adds an element with the specified key and value into the HashTable.
+ */
+#if defined(WITH_WINPR_DEPRECATED)
+int HashTable_Add(wHashTable* table, const void* key, const void* value)
+{
+	if (!HashTable_Insert(table, key, value))
+		return -1;
+	return 0;
+}
+#endif
+
+BOOL HashTable_Insert(wHashTable* table, const void* key, const void* value)
+{
+	BOOL rc = FALSE;
+	UINT32 hashValue = 0;
+	wKeyValuePair* pair = nullptr;
+	wKeyValuePair* newPair = nullptr;
+
+	WINPR_ASSERT(table);
+	if (!key || !value)
+		return FALSE;
+
+	if (table->synchronized)
+		EnterCriticalSection(&table->lock);
+
+	hashValue = table->hash(key) % table->numOfBuckets;
+	pair = table->bucketArray[hashValue];
+
+	while (pair && !HashTable_Equals(table, pair, key))
+		pair = pair->next;
+
+	if (pair)
+	{
+		if (pair->markedForRemove)
+		{
+			/* this entry was set to be removed but will be recycled instead */
+			table->pendingRemoves--;
+			pair->markedForRemove = FALSE;
+			table->numOfElements++;
+		}
+
+		if (pair->key != key)
+		{
+			setKey(table, pair, key);
+		}
+
+		if (pair->value != value)
+		{
+			setValue(table, pair, value);
+		}
+		rc = TRUE;
+	}
+	else
+	{
+		newPair = (wKeyValuePair*)calloc(1, sizeof(wKeyValuePair));
+
+		if (newPair)
+		{
+			setKey(table, newPair, key);
+			setValue(table, newPair, value);
+			newPair->next = table->bucketArray[hashValue];
+			newPair->markedForRemove = FALSE;
+			table->bucketArray[hashValue] = newPair;
+			table->numOfElements++;
+
+			if (!table->foreachRecursionLevel && table->upperRehashThreshold > table->idealRatio)
+			{
+				float elementToBucketRatio =
+				    (float)table->numOfElements / (float)table->numOfBuckets;
+
+				if (elementToBucketRatio > table->upperRehashThreshold)
+					HashTable_Rehash(table, 0);
+			}
+			rc = TRUE;
+		}
+	}
+
+	if (table->synchronized)
+		LeaveCriticalSection(&table->lock);
+
+	return rc;
+}
+
+/**
+ * Removes the element with the specified key from the HashTable.
+ */
+
+BOOL HashTable_Remove(wHashTable* table, const void* key)
+{
+	UINT32 hashValue = 0;
+	BOOL status = TRUE;
+	wKeyValuePair* pair = nullptr;
+	wKeyValuePair* previousPair = nullptr;
+
+	WINPR_ASSERT(table);
+	if (!key)
+		return FALSE;
+
+	if (table->synchronized)
+		EnterCriticalSection(&table->lock);
+
+	hashValue = table->hash(key) % table->numOfBuckets;
+	pair = table->bucketArray[hashValue];
+
+	while (pair && !HashTable_Equals(table, pair, key))
+	{
+		previousPair = pair;
+		pair = pair->next;
+	}
+
+	if (!pair)
+	{
+		status = FALSE;
+		goto out;
+	}
+
+	if (table->foreachRecursionLevel)
+	{
+		/* if we are running a HashTable_Foreach, just mark the entry for removal */
+		pair->markedForRemove = TRUE;
+		table->pendingRemoves++;
+		table->numOfElements--;
+		goto out;
+	}
+
+	if (previousPair)
+		previousPair->next = pair->next;
+	else
+		table->bucketArray[hashValue] = pair->next;
+
+	disposePair(table, pair);
+	table->numOfElements--;
+
+	if (!table->foreachRecursionLevel && table->lowerRehashThreshold > 0.0f)
+	{
+		float elementToBucketRatio = (float)table->numOfElements / (float)table->numOfBuckets;
+
+		if (elementToBucketRatio < table->lowerRehashThreshold)
+			HashTable_Rehash(table, 0);
+	}
+
+out:
+	if (table->synchronized)
+		LeaveCriticalSection(&table->lock);
+
+	return status;
+}
+
+/**
+ * Get an item value using key
+ */
+
+void* HashTable_GetItemValue(wHashTable* table, const void* key)
+{
+	void* value = nullptr;
+	wKeyValuePair* pair = nullptr;
+
+	WINPR_ASSERT(table);
+	if (!key)
+		return nullptr;
+
+	if (table->synchronized)
+		EnterCriticalSection(&table->lock);
+
+	pair = HashTable_Get(table, key);
+
+	if (pair && !pair->markedForRemove)
+		value = pair->value;
+
+	if (table->synchronized)
+		LeaveCriticalSection(&table->lock);
+
+	return value;
+}
+
+/**
+ * Set an item value using key
+ */
+
+BOOL HashTable_SetItemValue(wHashTable* table, const void* key, const void* value)
+{
+	BOOL status = TRUE;
+	wKeyValuePair* pair = nullptr;
+
+	WINPR_ASSERT(table);
+	if (!key)
+		return FALSE;
+
+	if (table->synchronized)
+		EnterCriticalSection(&table->lock);
+
+	pair = HashTable_Get(table, key);
+
+	if (!pair || pair->markedForRemove)
+		status = FALSE;
+	else
+	{
+		setValue(table, pair, value);
+	}
+
+	if (table->synchronized)
+		LeaveCriticalSection(&table->lock);
+
+	return status;
+}
+
+/**
+ * Removes all elements from the HashTable.
+ */
+
+void HashTable_Clear(wHashTable* table)
+{
+	wKeyValuePair* nextPair = nullptr;
+
+	WINPR_ASSERT(table);
+
+	if (table->synchronized)
+		EnterCriticalSection(&table->lock);
+
+	for (size_t index = 0; index < table->numOfBuckets; index++)
+	{
+		wKeyValuePair* pair = table->bucketArray[index];
+
+		while (pair)
+		{
+			nextPair = pair->next;
+
+			if (table->foreachRecursionLevel)
+			{
+				/* if we're in a foreach we just mark the entry for removal */
+				pair->markedForRemove = TRUE;
+				table->pendingRemoves++;
+			}
+			else
+			{
+				disposePair(table, pair);
+				pair = nextPair;
+			}
+		}
+
+		table->bucketArray[index] = nullptr;
+	}
+
+	table->numOfElements = 0;
+	if (table->foreachRecursionLevel == 0)
+		HashTable_Rehash(table, 5);
+
+	if (table->synchronized)
+		LeaveCriticalSection(&table->lock);
+}
+
+/**
+ * Gets the list of keys as an array
+ */
+
+size_t HashTable_GetKeys(wHashTable* table, ULONG_PTR** ppKeys)
+{
+	size_t iKey = 0;
+	size_t count = 0;
+	ULONG_PTR* pKeys = nullptr;
+	wKeyValuePair* nextPair = nullptr;
+
+	WINPR_ASSERT(table);
+
+	if (table->synchronized)
+		EnterCriticalSection(&table->lock);
+
+	iKey = 0;
+	count = table->numOfElements;
+	if (ppKeys)
+		*ppKeys = nullptr;
+
+	if (count < 1)
+	{
+		if (table->synchronized)
+			LeaveCriticalSection(&table->lock);
+
+		return 0;
+	}
+
+	pKeys = (ULONG_PTR*)calloc(count, sizeof(ULONG_PTR));
+
+	if (!pKeys)
+	{
+		if (table->synchronized)
+			LeaveCriticalSection(&table->lock);
+
+		return 0;
+	}
+
+	for (size_t index = 0; index < table->numOfBuckets; index++)
+	{
+		wKeyValuePair* pair = table->bucketArray[index];
+
+		while (pair)
+		{
+			nextPair = pair->next;
+			if (!pair->markedForRemove)
+				pKeys[iKey++] = (ULONG_PTR)pair->key;
+			pair = nextPair;
+		}
+	}
+
+	if (table->synchronized)
+		LeaveCriticalSection(&table->lock);
+
+	if (ppKeys)
+		*ppKeys = pKeys;
+	else
+		free(pKeys);
+	return count;
+}
+
+BOOL HashTable_Foreach(wHashTable* table, HASH_TABLE_FOREACH_FN fn, VOID* arg)
+{
+	BOOL ret = TRUE;
+
+	WINPR_ASSERT(table);
+	WINPR_ASSERT(fn);
+
+	if (table->synchronized)
+		EnterCriticalSection(&table->lock);
+
+	table->foreachRecursionLevel++;
+	for (size_t index = 0; index < table->numOfBuckets; index++)
+	{
+		for (wKeyValuePair* pair = table->bucketArray[index]; pair; pair = pair->next)
+		{
+			if (!pair->markedForRemove && !fn(pair->key, pair->value, arg))
+			{
+				ret = FALSE;
+				goto out;
+			}
+		}
+	}
+	table->foreachRecursionLevel--;
+
+	if (!table->foreachRecursionLevel && table->pendingRemoves)
+	{
+		/* if we're the last recursive foreach call, let's do the cleanup if needed */
+		wKeyValuePair** prevPtr = nullptr;
+		for (size_t index = 0; index < table->numOfBuckets; index++)
+		{
+			wKeyValuePair* nextPair = nullptr;
+			prevPtr = &table->bucketArray[index];
+			for (wKeyValuePair* pair = table->bucketArray[index]; pair;)
+			{
+				nextPair = pair->next;
+
+				if (pair->markedForRemove)
+				{
+					disposePair(table, pair);
+					*prevPtr = nextPair;
+				}
+				else
+				{
+					prevPtr = &pair->next;
+				}
+				pair = nextPair;
+			}
+		}
+		table->pendingRemoves = 0;
+	}
+
+out:
+	if (table->synchronized)
+		LeaveCriticalSection(&table->lock);
+	return ret;
+}
+
+/**
+ * Determines whether the HashTable contains a specific key.
+ */
+
+BOOL HashTable_Contains(wHashTable* table, const void* key)
+{
+	BOOL status = 0;
+	wKeyValuePair* pair = nullptr;
+
+	WINPR_ASSERT(table);
+	if (!key)
+		return FALSE;
+
+	if (table->synchronized)
+		EnterCriticalSection(&table->lock);
+
+	pair = HashTable_Get(table, key);
+	status = (pair && !pair->markedForRemove);
+
+	if (table->synchronized)
+		LeaveCriticalSection(&table->lock);
+
+	return status;
+}
+
+/**
+ * Determines whether the HashTable contains a specific key.
+ */
+
+BOOL HashTable_ContainsKey(wHashTable* table, const void* key)
+{
+	BOOL status = 0;
+	wKeyValuePair* pair = nullptr;
+
+	WINPR_ASSERT(table);
+	if (!key)
+		return FALSE;
+
+	if (table->synchronized)
+		EnterCriticalSection(&table->lock);
+
+	pair = HashTable_Get(table, key);
+	status = (pair && !pair->markedForRemove);
+
+	if (table->synchronized)
+		LeaveCriticalSection(&table->lock);
+
+	return status;
+}
+
+/**
+ * Determines whether the HashTable contains a specific value.
+ */
+
+BOOL HashTable_ContainsValue(wHashTable* table, const void* value)
+{
+	BOOL status = FALSE;
+
+	WINPR_ASSERT(table);
+	if (!value)
+		return FALSE;
+
+	if (table->synchronized)
+		EnterCriticalSection(&table->lock);
+
+	for (size_t index = 0; index < table->numOfBuckets; index++)
+	{
+		wKeyValuePair* pair = table->bucketArray[index];
+
+		while (pair)
+		{
+			if (!pair->markedForRemove && HashTable_Equals(table, pair, value))
+			{
+				status = TRUE;
+				break;
+			}
+
+			pair = pair->next;
+		}
+
+		if (status)
+			break;
+	}
+
+	if (table->synchronized)
+		LeaveCriticalSection(&table->lock);
+
+	return status;
+}
+
+/**
+ * Construction, Destruction
+ */
+
+wHashTable* HashTable_New(BOOL synchronized)
+{
+	wHashTable* table = (wHashTable*)calloc(1, sizeof(wHashTable));
+
+	if (!table)
+		goto fail;
+
+	table->synchronized = synchronized;
+	if (!InitializeCriticalSectionAndSpinCount(&(table->lock), 4000))
+		goto fail;
+	table->numOfBuckets = 64;
+	table->numOfElements = 0;
+	table->bucketArray = (wKeyValuePair**)calloc(table->numOfBuckets, sizeof(wKeyValuePair*));
+
+	if (!table->bucketArray)
+		goto fail;
+
+	table->idealRatio = 3.0f;
+	table->lowerRehashThreshold = 0.0f;
+	table->upperRehashThreshold = 15.0f;
+	table->hash = HashTable_PointerHash;
+	table->key.fnObjectEquals = HashTable_PointerCompare;
+	table->value.fnObjectEquals = HashTable_PointerCompare;
+
+	return table;
+fail:
+	WINPR_PRAGMA_DIAG_PUSH
+	WINPR_PRAGMA_DIAG_IGNORED_MISMATCHED_DEALLOC
+	HashTable_Free(table);
+	WINPR_PRAGMA_DIAG_POP
+	return nullptr;
+}
+
+void HashTable_Free(wHashTable* table)
+{
+	wKeyValuePair* pair = nullptr;
+	wKeyValuePair* nextPair = nullptr;
+
+	if (!table)
+		return;
+
+	if (table->bucketArray)
+	{
+		for (size_t index = 0; index < table->numOfBuckets; index++)
+		{
+			pair = table->bucketArray[index];
+
+			while (pair)
+			{
+				nextPair = pair->next;
+
+				disposePair(table, pair);
+				pair = nextPair;
+			}
+		}
+		free((void*)table->bucketArray);
+	}
+	DeleteCriticalSection(&(table->lock));
+
+	free(table);
+}
+
+void HashTable_Lock(wHashTable* table)
+{
+	WINPR_ASSERT(table);
+	EnterCriticalSection(&table->lock);
+}
+
+void HashTable_Unlock(wHashTable* table)
+{
+	WINPR_ASSERT(table);
+	LeaveCriticalSection(&table->lock);
+}
+
+wObject* HashTable_KeyObject(wHashTable* table)
+{
+	WINPR_ASSERT(table);
+	return &table->key;
+}
+
+wObject* HashTable_ValueObject(wHashTable* table)
+{
+	WINPR_ASSERT(table);
+	return &table->value;
+}
+
+BOOL HashTable_SetHashFunction(wHashTable* table, HASH_TABLE_HASH_FN fn)
+{
+	WINPR_ASSERT(table);
+	table->hash = fn;
+	return fn != nullptr;
+}
+
+BOOL HashTable_SetupForStringData(wHashTable* table, BOOL stringValues)
+{
+	wObject* obj = nullptr;
+
+	if (!HashTable_SetHashFunction(table, HashTable_StringHash))
+		return FALSE;
+
+	obj = HashTable_KeyObject(table);
+	obj->fnObjectEquals = HashTable_StringCompare;
+	obj->fnObjectNew = HashTable_StringClone;
+	obj->fnObjectFree = HashTable_StringFree;
+
+	if (stringValues)
+	{
+		obj = HashTable_ValueObject(table);
+		obj->fnObjectEquals = HashTable_StringCompare;
+		obj->fnObjectNew = HashTable_StringClone;
+		obj->fnObjectFree = HashTable_StringFree;
+	}
+	return TRUE;
+}