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/ProcessMappings.cpp b/libmemunreachable/ProcessMappings.cpp
new file mode 100644
index 0000000..7cca7c1
--- /dev/null
+++ b/libmemunreachable/ProcessMappings.cpp
@@ -0,0 +1,67 @@
+/*
+ * 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 <inttypes.h>
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <android-base/unique_fd.h>
+
+#include "LineBuffer.h"
+#include "ProcessMappings.h"
+#include "log.h"
+
+// This function is not re-entrant since it uses a static buffer for
+// the line data.
+bool ProcessMappings(pid_t pid, allocator::vector<Mapping>& mappings) {
+ char map_buffer[1024];
+ snprintf(map_buffer, sizeof(map_buffer), "/proc/%d/maps", pid);
+ int fd = open(map_buffer, O_RDONLY);
+ if (fd < 0) {
+ return false;
+ }
+ android::base::unique_fd fd_guard{fd};
+
+ LineBuffer line_buf(fd, map_buffer, sizeof(map_buffer));
+ char* line;
+ size_t line_len;
+ while (line_buf.GetLine(&line, &line_len)) {
+ int name_pos;
+ char perms[5];
+ Mapping mapping{};
+ if (sscanf(line, "%" SCNxPTR "-%" SCNxPTR " %4s %*x %*x:%*x %*d %n",
+ &mapping.begin, &mapping.end, perms, &name_pos) == 3) {
+ if (perms[0] == 'r') {
+ mapping.read = true;
+ }
+ if (perms[1] == 'w') {
+ mapping.write = true;
+ }
+ if (perms[2] == 'x') {
+ mapping.execute = true;
+ }
+ if (perms[3] == 'p') {
+ mapping.priv = true;
+ }
+ if ((size_t)name_pos < line_len) {
+ strlcpy(mapping.name, line + name_pos, sizeof(mapping.name));
+ }
+ mappings.emplace_back(mapping);
+ }
+ }
+ return true;
+}