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.
Bug: 27208635
Change-Id: Ia70bbf31f5b40ff71dab28cfd6cd06c5ef01a2d4
(cherry picked from commit bcb4ed3eaa92d23949d4ab33dbf1b2604bba8a18)
diff --git a/libmemunreachable/LeakPipe.cpp b/libmemunreachable/LeakPipe.cpp
new file mode 100644
index 0000000..080f8a7
--- /dev/null
+++ b/libmemunreachable/LeakPipe.cpp
@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#include <errno.h>
+#include <string.h>
+
+#include "LeakPipe.h"
+
+#include "log.h"
+
+bool LeakPipe::SendFd(int sock, int fd) {
+ struct msghdr hdr{};
+ struct iovec iov{};
+ unsigned int data = 0xfdfdfdfd;
+ alignas(struct cmsghdr) char cmsgbuf[CMSG_SPACE(sizeof(int))];
+
+ hdr.msg_iov = &iov;
+ hdr.msg_iovlen = 1;
+ iov.iov_base = &data;
+ iov.iov_len = sizeof(data);
+
+ hdr.msg_control = cmsgbuf;
+ hdr.msg_controllen = CMSG_LEN(sizeof(int));
+
+ struct cmsghdr* cmsg = CMSG_FIRSTHDR(&hdr);
+ cmsg->cmsg_len = CMSG_LEN(sizeof(int));
+ cmsg->cmsg_level = SOL_SOCKET;
+ cmsg->cmsg_type = SCM_RIGHTS;
+
+ *(int*)CMSG_DATA(cmsg) = fd;
+
+ int ret = sendmsg(sock, &hdr, 0);
+ if (ret < 0) {
+ ALOGE("failed to send fd: %s", strerror(errno));
+ return false;
+ }
+ if (ret == 0) {
+ ALOGE("eof when sending fd");
+ return false;
+ }
+
+ return true;
+}
+
+int LeakPipe::ReceiveFd(int sock) {
+ struct msghdr hdr{};
+ struct iovec iov{};
+ unsigned int data;
+ alignas(struct cmsghdr) char cmsgbuf[CMSG_SPACE(sizeof(int))];
+
+ hdr.msg_iov = &iov;
+ hdr.msg_iovlen = 1;
+ iov.iov_base = &data;
+ iov.iov_len = sizeof(data);
+
+ hdr.msg_control = cmsgbuf;
+ hdr.msg_controllen = CMSG_LEN(sizeof(int));
+
+ int ret = recvmsg(sock, &hdr, 0);
+ if (ret < 0) {
+ ALOGE("failed to receive fd: %s", strerror(errno));
+ return -1;
+ }
+ if (ret == 0) {
+ ALOGE("eof when receiving fd");
+ return -1;
+ }
+
+ struct cmsghdr* cmsg = CMSG_FIRSTHDR(&hdr);
+ if (cmsg == NULL || cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS) {
+ ALOGE("missing fd while receiving fd");
+ return -1;
+ }
+
+ return *(int*)CMSG_DATA(cmsg);
+}