* Made header includable by C code. In this case a KMessage structure

with the same size as the class is defined.
* The SetTo() methods do now accept an unspecified (negative) bufferSize
  in case of being told to initialize from the given buffer.
* Added handy Get*() methods returning a field element value or a
  supplied default value, if the field element doesn't exist.
* Added also handy Set*() methods setting the value of first element of
  a field, i.e. adding it, if it didn't exist before, otherwise
  replacing the old value. Only for fixed size types.
* Moved _FindType() inline template method into the header.
* Made the source file fit for use in the boot loader. If the macro
  KMESSAGE_CONTAINER_ONLY is defined, the message sending/receiving part
  is omitted.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@21605 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/kernel/util/KMessage.h

@@ -11,6 +11,10 @@
 #include <OS.h>
 #include <TypeConstants.h>
 
+
+#ifdef __cplusplus
+
+
 class BMessage;
 
 namespace BPrivate {
@@ -36,7 +40,7 @@ public:
 	status_t SetTo(uint32 what, uint32 flags = 0);
 	status_t SetTo(void *buffer, int32 bufferSize, uint32 what,
 		uint32 flags = 0);
-	status_t SetTo(const void *buffer, int32 bufferSize);
+	status_t SetTo(const void *buffer, int32 bufferSize = -1);
 	void Unset();
 
 	void SetWhat(uint32 what);
@@ -82,6 +86,33 @@ public:
 	inline status_t FindString(const char *name, int32 index,
 		const char **value) const;
 
+	inline bool GetBool(const char* name, bool defaultValue) const;
+	inline bool GetBool(const char* name, int32 index, bool defaultValue) const;
+	inline int8 GetInt8(const char* name, int8 defaultValue) const;
+	inline int8 GetInt8(const char* name, int32 index, int8 defaultValue) const;
+	inline int16 GetInt16(const char* name, int16 defaultValue) const;
+	inline int16 GetInt16(const char* name, int32 index,
+		int16 defaultValue) const;
+	inline int32 GetInt32(const char* name, int32 defaultValue) const;
+	inline int32 GetInt32(const char* name, int32 index,
+		int32 defaultValue) const;
+	inline int64 GetInt64(const char* name, int64 defaultValue) const;
+	inline int64 GetInt64(const char* name, int32 index,
+		int64 defaultValue) const;
+	inline const char* GetString(const char* name,
+		const char* defaultValue) const;
+	inline const char* GetString(const char* name, int32 index,
+		const char* defaultValue) const;
+
+	// fixed size fields only
+	status_t SetData(const char* name, type_code type, const void* data,
+		int32 numBytes);
+	inline status_t SetBool(const char* name, bool value);
+	inline status_t SetInt8(const char* name, int8 value);
+	inline status_t SetInt16(const char* name, int16 value);
+	inline status_t SetInt32(const char* name, int32 value);
+	inline status_t SetInt64(const char* name, int64 value);
+
 	// message delivery
 	team_id Sender() const;
 	int32 TargetToken() const;
@@ -129,7 +160,7 @@ private:
 	status_t _AddFieldData(KMessageField *field, const void *data,
 		int32 elementSize, int32 elementCount);
 
-	status_t _InitFromBuffer();
+	status_t _InitFromBuffer(bool sizeFromBuffer);
 	void _InitBuffer(uint32 what);
 
 	void _CheckBuffer();	// debugging only
@@ -139,6 +170,8 @@ private:
 	int32 _CapacityFor(int32 size);
 	template<typename T> inline status_t _FindType(const char* name,
 		type_code type, int32 index, T *value) const;
+	template<typename T> inline T _GetType(const char* name, type_code type,
+		int32 index, const T& defaultValue) const;
 
 	Header			fHeader;	// pointed to by fBuffer, if nothing is
 								// allocated
@@ -185,8 +218,9 @@ private:
 using BPrivate::KMessage;
 using BPrivate::KMessageField;
 
-// #pragma mark -
-// inline functions
+
+// #pragma mark - inline functions
+
 
 // AddBool
 inline
@@ -238,8 +272,30 @@ KMessage::AddString(const char *name, const char *value)
 	return AddData(name, B_STRING_TYPE, value, strlen(value) + 1, false);
 }
 
+
 // #pragma mark -
 
+
+// _FindType
+template<typename T>
+inline status_t
+KMessage::_FindType(const char* name, type_code type, int32 index,
+	T *value) const
+{
+	const void *data;
+	int32 size;
+	status_t error = FindData(name, type, index, &data, &size);
+	if (error != B_OK)
+		return error;
+
+	if (size != sizeof(T))
+		return B_BAD_DATA;
+
+	*value = *(T*)data;
+
+	return B_OK;
+}
+
 // FindBool
 inline
 status_t
@@ -337,4 +393,184 @@ KMessage::FindString(const char *name, int32 index, const char **value) const
 	return FindData(name, B_STRING_TYPE, index, (const void**)value, &size);
 }
 
+
+// _GetType
+template<typename T>
+inline T
+KMessage::_GetType(const char* name, type_code type, int32 index,
+	const T& defaultValue) const
+{
+	T value;
+	if (_FindType(name, type, index, &value) == B_OK)
+		return value;
+	return defaultValue;
+}
+
+
+// GetBool
+inline bool
+KMessage::GetBool(const char* name, bool defaultValue) const
+{
+	return _GetType(name, B_BOOL_TYPE, 0, defaultValue);
+}
+
+
+// GetBool
+inline bool
+KMessage::GetBool(const char* name, int32 index, bool defaultValue) const
+{
+	return _GetType(name, B_BOOL_TYPE, index, defaultValue);
+}
+
+// GetInt8
+inline int8
+KMessage::GetInt8(const char* name, int8 defaultValue) const
+{
+	return _GetType(name, B_INT8_TYPE, 0, defaultValue);
+}
+
+
+// GetInt8
+inline int8
+KMessage::GetInt8(const char* name, int32 index, int8 defaultValue) const
+{
+	return _GetType(name, B_INT8_TYPE, index, defaultValue);
+}
+
+
+// GetInt16
+inline int16
+KMessage::GetInt16(const char* name, int16 defaultValue) const
+{
+	return _GetType(name, B_INT16_TYPE, 0, defaultValue);
+}
+
+
+// GetInt16
+inline int16
+KMessage::GetInt16(const char* name, int32 index, int16 defaultValue) const
+{
+	return _GetType(name, B_INT16_TYPE, index, defaultValue);
+}
+
+
+// GetInt32
+inline int32
+KMessage::GetInt32(const char* name, int32 defaultValue) const
+{
+	return _GetType(name, B_INT32_TYPE, 0, defaultValue);
+}
+
+
+// GetInt32
+inline int32
+KMessage::GetInt32(const char* name, int32 index, int32 defaultValue) const
+{
+	return _GetType(name, B_INT32_TYPE, index, defaultValue);
+}
+
+
+// GetInt64
+inline int64
+KMessage::GetInt64(const char* name, int64 defaultValue) const
+{
+	return _GetType(name, B_INT64_TYPE, 0, defaultValue);
+}
+
+
+// GetInt64
+inline int64
+KMessage::GetInt64(const char* name, int32 index, int64 defaultValue) const
+{
+	return _GetType(name, B_INT64_TYPE, index, defaultValue);
+}
+
+
+// GetString
+inline const char*
+KMessage::GetString(const char* name, int32 index,
+	const char* defaultValue) const
+{
+	// don't use _GetType() here, since it checks field size == sizeof(T)
+	int32 size;
+	const char* value;
+	if (FindData(name, B_STRING_TYPE, index, (const void**)&value, &size)
+			== B_OK) {
+		return value;
+	}
+	return defaultValue;
+}
+
+
+// GetString
+inline const char*
+KMessage::GetString(const char* name, const char* defaultValue) const
+{
+	return GetString(name, 0, defaultValue);
+}
+
+
+// SetBool
+inline status_t
+KMessage::SetBool(const char* name, bool value)
+{
+	return SetData(name, B_BOOL_TYPE, &value, sizeof(bool));
+}
+
+
+// SetInt8
+inline status_t
+KMessage::SetInt8(const char* name, int8 value)
+{
+	return SetData(name, B_INT8_TYPE, &value, sizeof(int8));
+}
+
+
+// SetInt16
+inline status_t
+KMessage::SetInt16(const char* name, int16 value)
+{
+	return SetData(name, B_INT16_TYPE, &value, sizeof(int16));
+}
+
+
+// SetInt32
+inline status_t
+KMessage::SetInt32(const char* name, int32 value)
+{
+	return SetData(name, B_INT32_TYPE, &value, sizeof(int32));
+}
+
+
+// SetInt64
+inline status_t
+KMessage::SetInt64(const char* name, int64 value)
+{
+	return SetData(name, B_INT64_TYPE, &value, sizeof(int64));
+}
+
+
+#else	// !__cplusplus
+
+
+typedef struct KMessage {
+	struct Header {
+		uint32		magic;
+		int32		size;
+		uint32		what;
+		team_id		sender;
+		int32		targetToken;
+		port_id		replyPort;
+		int32		replyToken;
+	}				fHeader;
+	void*			fBuffer;
+	int32			fBufferCapacity;
+	uint32			fFlags;
+	int32			fLastFieldOffset;
+} KMessage;
+
+
+#endif	// !__cplusplus
+
+
 #endif	// KMESSAGE_H

src/system/kernel/messaging/KMessage.cpp

@@ -1,8 +1,10 @@
 /* 
- * Copyright 2005, Ingo Weinhold, [email protected]. All rights reserved.
- * Distributed under the terms of the MIT License.
+ * Copyright 2005-2007, Ingo Weinhold, [email protected].
+ * All rights reserved. Distributed under the terms of the MIT License.
  */
 
+#include "KMessage.h"
+
 #include <stdlib.h>
 #include <string.h>
 
@@ -10,7 +12,13 @@
 #include <KernelExport.h>
 #include <TypeConstants.h>
 
-#include "KMessage.h"
+#if defined(_BOOT_MODE)
+#	include <util/kernel_cpp.h>
+#else
+#	include <new>
+#endif
+
+using std::nothrow;
 
 // TODO: Add a field index using a hash map, so that lookup improves to O(1)
 // (is now O(n)).
@@ -141,21 +149,33 @@ status_t
 KMessage::SetTo(void *buffer, int32 bufferSize, uint32 what, uint32 flags)
 {
 	Unset();
-	if (!buffer || bufferSize < (int)sizeof(Header))
+
+	if (!buffer)
 		return B_BAD_VALUE;
+
+	if (bufferSize < 0) {
+		if (!(flags & KMESSAGE_INIT_FROM_BUFFER))
+			return B_BAD_VALUE;
+	} else if (bufferSize < (int)sizeof(Header))
+		return B_BAD_VALUE;
+
 	// if read-only, we need to init from the buffer, too
 	if (flags & KMESSAGE_READ_ONLY && !(flags & KMESSAGE_INIT_FROM_BUFFER))
 		return B_BAD_VALUE;
+
 	fBuffer = buffer;
 	fBufferCapacity = bufferSize;
 	fFlags = flags;
+
 	status_t error = B_OK;
 	if (flags & KMESSAGE_INIT_FROM_BUFFER)
-		error = _InitFromBuffer();
+		error = _InitFromBuffer(bufferSize < 0);
 	else
 		_InitBuffer(what);
+
 	if (error != B_OK)
 		Unset();
+
 	return error;
 }
 
@@ -325,6 +345,42 @@ KMessage::AddArray(const char *name, type_code type, const void *data,
 	return _AddFieldData(&field, data, elementSize, elementCount);
 }
 
+
+// SetData
+status_t
+KMessage::SetData(const char* name, type_code type, const void* data,
+	int32 numBytes)
+{
+	if (fBuffer != &fHeader && (fFlags & KMESSAGE_READ_ONLY))
+		return B_NOT_ALLOWED;
+
+	KMessageField field;
+
+	if (FindField(name, &field) == B_OK) {
+		// field already known
+		if (field.TypeCode() != type || !field.HasFixedElementSize()
+			|| field.ElementSize() != numBytes) {
+			return B_BAD_VALUE;
+		}
+
+		// if it has an element, just replace its value
+		if (field.CountElements() > 0) {
+			const void* element = field.ElementAt(0);
+			memcpy(const_cast<void*>(element), data, numBytes);
+			return B_OK;
+		}
+	} else {
+		// no such field yet -- add it
+		status_t error = _AddField(name, type, numBytes, &field);
+		if (error != B_OK)
+			return error;
+	}
+
+	// we've got an empty field -- add the element
+	return _AddFieldData(&field, data, numBytes, 1);
+}
+
+
 // FindData
 status_t
 KMessage::FindData(const char *name, type_code type, const void **data,
@@ -380,6 +436,9 @@ KMessage::ReplyToken() const
 	return _Header()->replyToken;
 }
 
+
+#ifndef KMESSAGE_CONTAINER_ONLY
+
 // SendTo
 status_t
 KMessage::SendTo(port_id targetPort, int32 targetToken, port_id replyPort,
@@ -512,6 +571,9 @@ KMessage::ReceiveFrom(port_id fromPort, bigtime_t timeout)
 		KMESSAGE_OWNS_BUFFER | KMESSAGE_INIT_FROM_BUFFER);
 }
 
+#endif	// !KMESSAGE_CONTAINER_ONLY
+
+
 // _Header
 KMessage::Header *
 KMessage::_Header() const
@@ -631,18 +693,24 @@ KMessage::_AddFieldData(KMessageField *field, const void *data,
 
 // _InitFromBuffer
 status_t
-KMessage::_InitFromBuffer()
+KMessage::_InitFromBuffer(bool sizeFromBuffer)
 {
-	if (!fBuffer || fBufferCapacity < (int)sizeof(Header)
-		|| _Align(fBuffer) != fBuffer) {
+	if (!fBuffer || _Align(fBuffer) != fBuffer)
 		return B_BAD_DATA;
-	}
-	// check header
 	Header *header = _Header();
+
+	if (sizeFromBuffer)
+		fBufferCapacity = header->size;
+
+	if (fBufferCapacity < (int)sizeof(Header))
+		return B_BAD_DATA;
+
+	// check header
 	if (header->magic != kMessageHeaderMagic)
 		return B_BAD_DATA;
 	if (header->size < (int)sizeof(Header) || header->size > fBufferCapacity)
 		return B_BAD_DATA;
+
 	// check the fields
 	FieldHeader *fieldHeader = NULL;
 	uint8 *data = (uint8*)_FirstFieldHeader();
@@ -721,7 +789,7 @@ void
 KMessage::_CheckBuffer()
 {
 	int32 lastFieldOffset = fLastFieldOffset;
-	if (_InitFromBuffer() != B_OK) {
+	if (_InitFromBuffer(false) != B_OK) {
 		PANIC("internal data mangled");
 	}
 	if (fLastFieldOffset != lastFieldOffset) {
@@ -779,24 +847,6 @@ KMessage::_CapacityFor(int32 size)
 		* kMessageReallocChunkSize;
 }
 
-// _FindType
-template<typename T>
-inline
-status_t
-KMessage::_FindType(const char* name, type_code type, int32 index,
-	T *value) const
-{
-	const void *data;
-	int32 size;
-	status_t error = FindData(name, type, index, &data, &size);
-	if (error != B_OK)
-		return error;
-	if (size != sizeof(T))
-		return B_BAD_DATA;
-	*value = *(T*)data;
-	return B_OK;
-}
-
 
 // #pragma mark -