1 files changed, 217 insertions, 0 deletions
diff --git a/tools/gator/daemon/Buffer.cpp b/tools/gator/daemon/Buffer.cpp
new file mode 100644
index 00000000000..c7abbf3a182
--- /dev/null
+++ b/tools/gator/daemon/Buffer.cpp
@@ -0,0 +1,217 @@
+/**
+ * Copyright (C) ARM Limited 2013. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "Buffer.h"
+
+#include "Logging.h"
+#include "Sender.h"
+#include "SessionData.h"
+
+#define mask (size - 1)
+
+Buffer::Buffer (const int32_t core, const int32_t buftype, const int size, sem_t *const readerSem) : core(core), buftype(buftype), size(size), readPos(0), writePos(0), commitPos(0), available(true), done(false), buf(new char[size]), commitTime(gSessionData->mLiveRate), readerSem(readerSem) {
+	if ((size & mask) != 0) {
+		logg->logError(__FILE__, __LINE__, "Buffer size is not a power of 2");
+		handleException();
+	}
+	frame();
+}
+
+Buffer::~Buffer () {
+	delete [] buf;
+}
+
+void Buffer::write (Sender * const sender) {
+	if (!commitReady()) {
+		return;
+	}
+
+	// determine the size of two halves
+	int length1 = commitPos - readPos;
+	char * buffer1 = buf + readPos;
+	int length2 = 0;
+	char * buffer2 = buf;
+	if (length1 < 0) {
+		length1 = size - readPos;
+		length2 = commitPos;
+	}
+
+	logg->logMessage("Sending data length1: %i length2: %i", length1, length2);
+
+	// start, middle or end
+	if (length1 > 0) {
+		sender->writeData(buffer1, length1, RESPONSE_APC_DATA);
+	}
+
+	// possible wrap around
+	if (length2 > 0) {
+		sender->writeData(buffer2, length2, RESPONSE_APC_DATA);
+	}
+
+	readPos = commitPos;
+}
+
+bool Buffer::commitReady () const {
+	return commitPos != readPos;
+}
+
+int Buffer::bytesAvailable () const {
+	int filled = writePos - readPos;
+	if (filled < 0) {
+		filled += size;
+	}
+
+	int remaining = size - filled;
+
+	if (available) {
+		// Give some extra room; also allows space to insert the overflow error packet
+		remaining -= 200;
+	} else {
+		// Hysteresis, prevents multiple overflow messages
+		remaining -= 2000;
+	}
+
+	return remaining;
+}
+
+bool Buffer::checkSpace (const int bytes) {
+	const int remaining = bytesAvailable();
+
+	if (remaining < bytes) {
+		available = false;
+	} else {
+		available = true;
+	}
+
+	return available;
+}
+
+void Buffer::commit (const uint64_t time) {
+	// post-populate the length, which does not include the response type length nor the length itself, i.e. only the length of the payload
+	const int typeLength = gSessionData->mLocalCapture ? 0 : 1;
+	int length = writePos - commitPos;
+	if (length < 0) {
+		length += size;
+	}
+	length = length - typeLength - sizeof(int32_t);
+	for (size_t byte = 0; byte < sizeof(int32_t); byte++) {
+		buf[(commitPos + typeLength + byte) & mask] = (length >> byte * 8) & 0xFF;
+	}
+
+	logg->logMessage("Committing data readPos: %i writePos: %i commitPos: %i", readPos, writePos, commitPos);
+	commitPos = writePos;
+
+	if (gSessionData->mLiveRate > 0) {
+		while (time > commitTime) {
+			commitTime += gSessionData->mLiveRate;
+		}
+	}
+
+	if (!done) {
+		frame();
+	}
+
+	// send a notification that data is ready
+	sem_post(readerSem);
+}
+
+void Buffer::check (const uint64_t time) {
+	int filled = writePos - commitPos;
+	if (filled < 0) {
+		filled += size;
+	}
+	if (filled >= ((size * 3) / 4) || (gSessionData->mLiveRate > 0 && time >= commitTime)) {
+		commit(time);
+	}
+}
+
+void Buffer::packInt (int32_t x) {
+	int packedBytes = 0;
+	int more = true;
+	while (more) {
+		// low order 7 bits of x
+		char b = x & 0x7f;
+		x >>= 7;
+
+		if ((x == 0 && (b & 0x40) == 0) || (x == -1 && (b & 0x40) != 0)) {
+			more = false;
+		} else {
+			b |= 0x80;
+		}
+
+		buf[(writePos + packedBytes) & mask] = b;
+		packedBytes++;
+	}
+
+	writePos = (writePos + packedBytes) & mask;
+}
+
+void Buffer::packInt64 (int64_t x) {
+	int packedBytes = 0;
+	int more = true;
+	while (more) {
+		// low order 7 bits of x
+		char b = x & 0x7f;
+		x >>= 7;
+
+		if ((x == 0 && (b & 0x40) == 0) || (x == -1 && (b & 0x40) != 0)) {
+			more = false;
+		} else {
+			b |= 0x80;
+		}
+
+		buf[(writePos + packedBytes) & mask] = b;
+		packedBytes++;
+	}
+
+	writePos = (writePos + packedBytes) & mask;
+}
+
+void Buffer::frame () {
+	if (!gSessionData->mLocalCapture) {
+		packInt(RESPONSE_APC_DATA);
+	}
+	// Reserve space for the length
+	writePos += sizeof(int32_t);
+	packInt(buftype);
+	packInt(core);
+}
+
+bool Buffer::eventHeader (const uint64_t curr_time) {
+	bool retval = false;
+	if (checkSpace(MAXSIZE_PACK32 + MAXSIZE_PACK64)) {
+		packInt(0);	// key of zero indicates a timestamp
+		packInt64(curr_time);
+		retval = true;
+	}
+
+	return retval;
+}
+
+void Buffer::event (const int32_t key, const int32_t value) {
+	if (checkSpace(2 * MAXSIZE_PACK32)) {
+		packInt(key);
+		packInt(value);
+	}
+}
+
+void Buffer::event64 (const int64_t key, const int64_t value) {
+	if (checkSpace(2 * MAXSIZE_PACK64)) {
+		packInt64(key);
+		packInt64(value);
+	}
+}
+
+void Buffer::setDone () {
+	done = true;
+	commit(0);
+}
+
+bool Buffer::isDone () const {
+	return done && readPos == commitPos && commitPos == writePos;
+}