Merge "Use std::unique_ptr in FileDescriptorTable" into main (14b1b592) · Commits · e / os / android_frameworks_base

core/jni/fd_utils.cpp

+14 −18

Original line number	Diff line number	Diff line
		@@ -17,6 +17,7 @@
		#include "fd_utils.h"

		#include <algorithm>
		#include <utility>

		#include <fcntl.h>
		#include <grp.h>
		@@ -174,7 +175,7 @@ FileDescriptorAllowlist* FileDescriptorAllowlist::instance_ = nullptr;
		class FileDescriptorInfo {
		public:
		// Create a FileDescriptorInfo for a given file descriptor.
		static FileDescriptorInfo* CreateFromFd(int fd, fail_fn_t fail_fn);
		static std::unique_ptr<FileDescriptorInfo> CreateFromFd(int fd, fail_fn_t fail_fn);

		// Checks whether the file descriptor associated with this object refers to
		// the same description.
		@@ -213,7 +214,7 @@ class FileDescriptorInfo {
		DISALLOW_COPY_AND_ASSIGN(FileDescriptorInfo);
		};

		FileDescriptorInfo* FileDescriptorInfo::CreateFromFd(int fd, fail_fn_t fail_fn) {
		std::unique_ptr<FileDescriptorInfo> FileDescriptorInfo::CreateFromFd(int fd, fail_fn_t fail_fn) {
		struct stat f_stat;
		// This should never happen; the zygote should always have the right set
		// of permissions required to stat all its open files.
		@@ -234,7 +235,7 @@ FileDescriptorInfo* FileDescriptorInfo::CreateFromFd(int fd, fail_fn_t fail_fn)
		socket_name.c_str(), fd));
		}

		return new FileDescriptorInfo(fd);
		return std::unique_ptr<FileDescriptorInfo>(new FileDescriptorInfo(fd));
		}

		// We only handle allowlisted regular files and character devices. Allowlisted
		@@ -315,7 +316,8 @@ FileDescriptorInfo* FileDescriptorInfo::CreateFromFd(int fd, fail_fn_t fail_fn)
		int open_flags = fs_flags & (kOpenFlags);
		fs_flags = fs_flags & (~(kOpenFlags));

		return new FileDescriptorInfo(f_stat, file_path, fd, open_flags, fd_flags, fs_flags, offset);
		return std::unique_ptr<FileDescriptorInfo>(
		new FileDescriptorInfo(f_stat, file_path, fd, open_flags, fd_flags, fs_flags, offset));
		}

		bool FileDescriptorInfo::RefersToSameFile() const {
		@@ -482,11 +484,11 @@ static std::unique_ptr<std::set<int>> GetOpenFdsIgnoring(const std::vector<int>&
		FileDescriptorTable* FileDescriptorTable::Create(const std::vector<int>& fds_to_ignore,
		fail_fn_t fail_fn) {
		std::unique_ptr<std::set<int>> open_fds = GetOpenFdsIgnoring(fds_to_ignore, fail_fn);
		std::unordered_map<int, FileDescriptorInfo*> open_fd_map;
		std::unordered_map<int, std::unique_ptr<FileDescriptorInfo>> open_fd_map;
		for (auto fd : *open_fds) {
		open_fd_map[fd] = FileDescriptorInfo::CreateFromFd(fd, fail_fn);
		}
		return new FileDescriptorTable(open_fd_map);
		return new FileDescriptorTable(std::move(open_fd_map));
		}

		static std::unique_ptr<std::set<int>> GetOpenFdsIgnoring(const std::vector<int>& fds_to_ignore,
		@@ -535,9 +537,9 @@ void FileDescriptorTable::Restat(const std::vector<int>& fds_to_ignore, fail_fn_

		// Reopens all file descriptors that are contained in the table.
		void FileDescriptorTable::ReopenOrDetach(fail_fn_t fail_fn) {
		std::unordered_map<int, FileDescriptorInfo*>::const_iterator it;
		std::unordered_map<int, std::unique_ptr<FileDescriptorInfo>>::const_iterator it;
		for (it = open_fd_map_.begin(); it != open_fd_map_.end(); ++it) {
		const FileDescriptorInfo* info = it->second;
		const FileDescriptorInfo* info = it->second.get();
		if (info == nullptr) {
		return;
		} else {
		@@ -547,15 +549,11 @@ void FileDescriptorTable::ReopenOrDetach(fail_fn_t fail_fn) {
		}

		FileDescriptorTable::FileDescriptorTable(
		const std::unordered_map<int, FileDescriptorInfo*>& map)
		: open_fd_map_(map) {
		std::unordered_map<int, std::unique_ptr<FileDescriptorInfo>> map)
		: open_fd_map_(std::move(map)) {
		}

		FileDescriptorTable::~FileDescriptorTable() {
		for (auto& it : open_fd_map_) {
		delete it.second;
		}
		}
		FileDescriptorTable::~FileDescriptorTable() {}

		void FileDescriptorTable::RestatInternal(std::set<int>& open_fds, fail_fn_t fail_fn) {
		// ART creates a file through memfd for optimization purposes. We make sure
		@@ -569,7 +567,7 @@ void FileDescriptorTable::RestatInternal(std::set<int>& open_fds, fail_fn_t fail
		// (b) they refer to the same file.
		//
		// We'll only store the last error message.
		std::unordered_map<int, FileDescriptorInfo*>::iterator it = open_fd_map_.begin();
		std::unordered_map<int, std::unique_ptr<FileDescriptorInfo>>::iterator it = open_fd_map_.begin();
		while (it != open_fd_map_.end()) {
		std::set<int>::const_iterator element = open_fds.find(it->first);
		if (element == open_fds.end()) {
		@@ -580,7 +578,6 @@ void FileDescriptorTable::RestatInternal(std::set<int>& open_fds, fail_fn_t fail
		// TODO(narayan): This will be an error in a future android release.
		// error = true;
		// ALOGW("Zygote closed file descriptor %d.", it->first);
		delete it->second;
		it = open_fd_map_.erase(it);
		} else {
		// The entry from the file descriptor table is still open. Restat
		@@ -588,7 +585,6 @@ void FileDescriptorTable::RestatInternal(std::set<int>& open_fds, fail_fn_t fail
		if (!it->second->RefersToSameFile()) {
		// The file descriptor refers to a different description. We must
		// update our entry in the table.
		delete it->second;
		it->second = FileDescriptorInfo::CreateFromFd(*element, fail_fn);
		} else {
		// It's the same file. Nothing to do here. Move on to the next open

core/jni/fd_utils.h

+3 −2

Original line number	Diff line number	Diff line
		@@ -17,6 +17,7 @@
		#ifndef FRAMEWORKS_BASE_CORE_JNI_FD_UTILS_H_
		#define FRAMEWORKS_BASE_CORE_JNI_FD_UTILS_H_

		#include <memory>
		#include <set>
		#include <string>
		#include <unordered_map>
		@@ -98,12 +99,12 @@ class FileDescriptorTable {
		void ReopenOrDetach(fail_fn_t fail_fn);

		private:
		explicit FileDescriptorTable(const std::unordered_map<int, FileDescriptorInfo*>& map);
		explicit FileDescriptorTable(std::unordered_map<int, std::unique_ptr<FileDescriptorInfo>> map);

		void RestatInternal(std::set<int>& open_fds, fail_fn_t fail_fn);

		// Invariant: All values in this unordered_map are non-NULL.
		std::unordered_map<int, FileDescriptorInfo*> open_fd_map_;
		std::unordered_map<int, std::unique_ptr<FileDescriptorInfo>> open_fd_map_;

		DISALLOW_COPY_AND_ASSIGN(FileDescriptorTable);
		};