platform_system_core/libmemunreachable/ProcessMappings.cpp
Colin Cross bcb4ed3eaa 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
2016-02-08 17:08:49 -08:00

67 lines
1.9 KiB
C++

/*
* 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;
}