Untested, new clever pointer voodoo class for binary-safe ziplinks output buffers

PLUS: Fix for random epoll dispatchevents crashes.


git-svn-id: http://svn.inspircd.org/repository/trunk/inspircd@5926 e03df62e-2008-0410-955e-edbf42e46eb7

1 files changed, 139 insertions, 81 deletions

diff --git a/src/modules/extra/m_ziplink.cpp b/src/modules/extra/m_ziplink.cpp
index 27902add7..0647517c2 100644
--- a/src/modules/extra/m_ziplink.cpp
+++ b/src/modules/extra/m_ziplink.cpp
@@ -41,10 +41,105 @@
  */
 
 
-enum izip_status { IZIP_WAITFIRST, IZIP_OPEN, IZIP_CLOSED };
+enum izip_status { IZIP_OPEN, IZIP_CLOSED };
 
 const unsigned int CHUNK = 16384;
 
+class CountedBuffer : public classbase
+{
+	int bufptr;            /* Current tail location */
+	unsigned char* buffer; /* Current buffer contents */
+	int bufsz;             /* Current buffer size */
+	int amount_expected;   /* Amount of data expected */
+	int amount_read;       /* Amount of data read so far */
+ public:
+	CountedBuffer()
+	{
+		bufsz = 1024;
+		buffer = new unsigned char[bufsz + 1];
+		bufptr = 0;
+		amount_read = 0;
+	}
+
+	~CountedBuffer()
+	{
+		delete[] buffer;
+	}
+
+	void AddData(unsigned char* data, int data_length)
+	{
+		if ((data_length + bufptr) > bufsz)
+		{
+			/* Buffer is too small, enlarge it and copy contents */
+			int old_bufsz = bufsz;
+			unsigned char* temp = buffer;
+
+			bufsz += data_length;
+			buffer = new unsigned char[bufsz + 1];
+
+			memcpy(buffer, temp, old_bufsz);
+
+			delete[] temp;
+		}
+
+		memcpy(buffer + bufptr, data, data_length);
+		bufptr += data_length;
+		amount_read += data_length;
+
+		if ((!amount_expected) && (amount_read >= 4))
+		{
+			/* We have enough to read an int */
+			int* size = (int*)buffer;
+			amount_expected = ntohl(*size);
+		}
+	}
+
+	int GetFrame(unsigned char* frame, int maxsize)
+	{
+		if (amount_expected)
+		{
+			/* We know how much we're expecting...
+			 * Do we have enough yet?
+			 */
+			if ((amount_read - 4) >= amount_expected)
+			{
+				int amt_ex = amount_expected;
+				/* Yes, we have enough now */
+				memcpy(frame, buffer + 4, amount_expected > maxsize ? maxsize : amount_expected);
+				RemoveFirstFrame();
+				return (amt_ex > maxsize) ? maxsize : amt_ex;
+			}
+		}
+		/* Not enough for a frame yet, COME AGAIN! */
+		return 0;
+	}
+
+	void RemoveFirstFrame()
+	{
+		unsigned char* temp = buffer;
+
+		bufsz -= (amount_expected + 4);
+		buffer = new unsigned char[bufsz + 1];
+
+		memcpy(buffer, temp + amount_expected, bufsz);
+
+		amount_read -= (amount_expected + 4);
+		
+		if (amount_read >= 4)
+		{
+			/* We have enough to read an int */
+			int* size = (int*)buffer;
+			amount_expected = ntohl(*size);
+		}
+		else
+			amount_expected = 0;
+
+		bufptr = 0;
+
+		delete[] temp;
+	}
+};
+
 /** Represents an ZIP user's extra data
  */
 class izip_session : public classbase
@@ -55,7 +150,7 @@ class izip_session : public classbase
 	izip_status status;
 	int need_bytes;
 	int fd;
-	std::string inbuf;
+	CountedBuffer* inbuf;
 };
 
 class ModuleZLib : public Module
@@ -157,9 +252,9 @@ class ModuleZLib : public Module
 	
 		/* allocate deflate state */
 		session->fd = fd;
-		session->status = IZIP_WAITFIRST;
+		session->status = IZIP_OPEN;
 
-		session->need_bytes = 0;
+		session->inbuf = new CountedBuffer();
 
 		session->c_stream.zalloc = (alloc_func)0;
 		session->c_stream.zfree = (free_func)0;
@@ -188,108 +283,67 @@ class ModuleZLib : public Module
 		if (session->status == IZIP_CLOSED)
 			return 1;
 
-		int size = 0;
-
-		if (session->need_bytes)
-		{
-			size = session->need_bytes;
-		}
-		else
-		{
-			if (read(fd, &size, sizeof(size)) != sizeof(size))
-				return 0;
-			size = ntohl(size);
-		}
-
-		ServerInstance->Log(DEBUG,"Size of frame to read: %d%s", size, session->need_bytes ? " (remainder of last frame)" : "");
+		unsigned char compr[CHUNK + 1];
 
-		unsigned char compr[size+1+session->need_bytes];
+		readresult = read(fd, compr, CHUNK);
 
-		readresult = read(fd, compr + session->need_bytes, size);
-
-		if (readresult == size)
+		if (readresult > 0)
 		{
-			if(session->status == IZIP_WAITFIRST)
-			{
-				session->status = IZIP_OPEN;
-			}
-
-			/* Reassemble first part of last frame */
-			if (session->need_bytes)
-			{
-				for (size_t i = 0; i < session->inbuf.length(); i++)
-					compr[i] = session->inbuf[i];
-			}
-
-			session->d_stream.next_in  = (Bytef*)compr;
-			session->d_stream.avail_in = 0;
-			session->d_stream.next_out = (Bytef*)buffer;
-			if (inflateInit(&session->d_stream) != Z_OK)
-				return -EBADF;
-			session->status = IZIP_OPEN;
-
-			while ((session->d_stream.total_out < count) && (session->d_stream.total_in < (unsigned int)readresult))
-			{
-				session->d_stream.avail_in = session->d_stream.avail_out = 1; /* force small buffers */
-				if (inflate(&session->d_stream, Z_NO_FLUSH) == Z_STREAM_END)
-					break;
-			}
-
-			inflateEnd(&session->d_stream);
-
-			total_in_compressed += readresult;
-			readresult = session->d_stream.total_out;
-			total_in_uncompressed += session->d_stream.total_out;
-
-			buffer[readresult] = 0;
-			session->need_bytes = 0;
-		}
-		else
-		{
-			/* We need to buffer here */
-			ServerInstance->Log(DEBUG,"Didnt read whole frame, got %d bytes of %d!", readresult, size);
-			session->need_bytes = ((readresult > -1) ? (size - readresult) : (size));
-			if (readresult > 0)
+			session->inbuf->AddData(compr, readresult);
+	
+			int size = session->inbuf->GetFrame(compr, CHUNK);
+			if (size)
 			{
-				/* Do it this way because it needs to be binary safe */
-				for (int i = 0; i < readresult; i++)
-					session->inbuf += compr[i];
+	
+				session->d_stream.next_in  = (Bytef*)compr;
+				session->d_stream.avail_in = 0;
+				session->d_stream.next_out = (Bytef*)buffer;
+				if (inflateInit(&session->d_stream) != Z_OK)
+					return -EBADF;
+	
+				while ((session->d_stream.total_out < count) && (session->d_stream.total_in < (unsigned int)size))
+				{
+					session->d_stream.avail_in = session->d_stream.avail_out = 1;
+					if (inflate(&session->d_stream, Z_NO_FLUSH) == Z_STREAM_END)
+						break;
+				}
+	
+				inflateEnd(&session->d_stream);
+	
+				total_in_compressed += readresult;
+				readresult = session->d_stream.total_out;
+				total_in_uncompressed += session->d_stream.total_out;
+	
+				buffer[session->d_stream.total_out] = 0;
 			}
 		}
-
 		return (readresult > 0);
 	}
 
 	virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 	{
+		izip_session* session = &sessions[fd];
 		int ocount = count;
+
 		if (!count)
 		{
 			ServerInstance->Log(DEBUG,"Nothing to do!");
 			return 1;
 		}
 
-		unsigned char compr[count*2+4];
-
-		izip_session* session = &sessions[fd];
-
-		if(session->status == IZIP_WAITFIRST)
+		if(session->status != IZIP_OPEN)
 		{
-			session->status = IZIP_OPEN;
+			CloseSession(session);
+			return 0;
 		}
 
+		unsigned char compr[count*2+4];
+
 		if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 		{
 			ServerInstance->Log(DEBUG,"Deflate init failed");
 		}
 
-		if(session->status != IZIP_OPEN)
-		{
-			ServerInstance->Log(DEBUG,"State not open!");
-			CloseSession(session);
-			return 0;
-		}
-
 		session->c_stream.next_in  = (Bytef*)buffer;
 		session->c_stream.next_out = compr+4;
 
@@ -329,7 +383,11 @@ class ModuleZLib : public Module
 	
 	void CloseSession(izip_session* session)
 	{
-		session->status = IZIP_CLOSED;
+		if (session->status = IZIP_OPEN)
+		{
+			session->status = IZIP_CLOSED;
+			delete session->inbuf;
+		}
 	}
 
 };