imprecise mark and sweep native memory leak detector
libmemunreachable uses an imprecise mark and sweep pass over all memory
allocated by jemalloc in order to find unreachable allocations.
Change-Id: Ia70bbf31f5b40ff71dab28cfd6cd06c5ef01a2d4
diff --git a/libmemunreachable/LineBuffer.cpp b/libmemunreachable/LineBuffer.cpp
new file mode 100644
index 0000000..d3580c0
--- /dev/null
+++ b/libmemunreachable/LineBuffer.cpp
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * 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.
+ */
+
+// Copied from system/extras/memory_replay/LineBuffer.cpp
+// TODO(ccross): find a way to share between libmemunreachable and memory_replay?
+
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "LineBuffer.h"
+
+LineBuffer::LineBuffer(int fd, char* buffer, size_t buffer_len) : fd_(fd), buffer_(buffer), buffer_len_(buffer_len) {
+}
+
+bool LineBuffer::GetLine(char** line, size_t* line_len) {
+ while (true) {
+ if (bytes_ > 0) {
+ char* newline = reinterpret_cast<char*>(memchr(buffer_ + start_, '\n', bytes_));
+ if (newline != nullptr) {
+ *newline = '\0';
+ *line = buffer_ + start_;
+ start_ = newline - buffer_ + 1;
+ bytes_ -= newline - *line + 1;
+ *line_len = newline - *line;
+ return true;
+ }
+ }
+ if (start_ > 0) {
+ // Didn't find anything, copy the current to the front of the buffer.
+ memmove(buffer_, buffer_ + start_, bytes_);
+ start_ = 0;
+ }
+ ssize_t bytes = TEMP_FAILURE_RETRY(read(fd_, buffer_ + bytes_, buffer_len_ - bytes_ - 1));
+ if (bytes <= 0) {
+ if (bytes_ > 0) {
+ // The read data might not contain a nul terminator, so add one.
+ buffer_[bytes_] = '\0';
+ *line = buffer_ + start_;
+ *line_len = bytes_;
+ bytes_ = 0;
+ start_ = 0;
+ return true;
+ }
+ return false;
+ }
+ bytes_ += bytes;
+ }
+}