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swift-mirror/lib/AST/PluginRegistry.cpp

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//===--- PluginRegistry.cpp -----------------------------------------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2023 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
#include "swift/AST/PluginRegistry.h"
#include "swift/Basic/Defer.h"
#include "swift/Basic/LLVM.h"
#include "swift/Basic/Program.h"
#include "swift/Basic/Sandbox.h"
#include "swift/Basic/StringExtras.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Config/config.h"
#include <signal.h>
#if defined(_WIN32)
#define WIN32_LEAN_AND_MEAN
#define NOMINMAX
#include <windows.h>
#else
#include <dlfcn.h>
#endif
#if HAVE_UNISTD_H
#include <unistd.h>
#elif defined(_WIN32)
#include <io.h>
#endif
using namespace swift;
PluginRegistry::PluginRegistry() {
dumpMessaging = ::getenv("SWIFT_DUMP_PLUGIN_MESSAGING") != nullptr;
}
llvm::Expected<LoadedLibraryPlugin *>
PluginRegistry::loadLibraryPlugin(StringRef path) {
std::lock_guard<std::mutex> lock(mtx);
auto &storage = LoadedPluginLibraries[path];
if (storage) {
// Already loaded.
return storage.get();
}
void *lib = nullptr;
#if defined(_WIN32)
lib = LoadLibraryA(path.str().c_str());
if (!lib) {
std::error_code ec(GetLastError(), std::system_category());
return llvm::errorCodeToError(ec);
}
#else
lib = dlopen(path.str().c_str(), RTLD_LAZY | RTLD_LOCAL);
if (!lib) {
return llvm::createStringError(llvm::inconvertibleErrorCode(), dlerror());
}
#endif
storage = std::make_unique<LoadedLibraryPlugin>(lib, path);
return storage.get();
}
void *LoadedLibraryPlugin::getAddressOfSymbol(const char *symbolName) {
auto &cached = resolvedSymbols[symbolName];
if (cached)
return cached;
#if defined(_WIN32)
cached = GetProcAddress(static_cast<HMODULE>(handle), symbolName);
#else
cached = dlsym(handle, symbolName);
#endif
return cached;
}
llvm::Expected<LoadedExecutablePlugin *>
PluginRegistry::loadExecutablePlugin(StringRef path, bool disableSandbox) {
llvm::sys::fs::file_status stat;
if (auto err = llvm::sys::fs::status(path, stat)) {
return llvm::errorCodeToError(err);
}
std::lock_guard<std::mutex> lock(mtx);
// See if the plugin is already loaded.
auto &storage = LoadedPluginExecutables[path];
if (storage) {
// See if the loaded one is still usable.
if (storage->getLastModificationTime() == stat.getLastModificationTime())
return storage.get();
// The plugin is updated. Close the previously opened plugin.
storage = nullptr;
}
if (!llvm::sys::fs::exists(stat)) {
return llvm::createStringError(std::errc::no_such_file_or_directory,
"not found");
}
if (!llvm::sys::fs::can_execute(path)) {
return llvm::createStringError(std::errc::permission_denied,
"not executable");
}
auto plugin = std::make_unique<LoadedExecutablePlugin>(
path, stat.getLastModificationTime(), disableSandbox);
plugin->setDumpMessaging(dumpMessaging);
// Launch here to see if it's actually executable, and diagnose (by returning
// an error) if necessary.
if (auto error = plugin->spawnIfNeeded()) {
return std::move(error);
}
storage = std::move(plugin);
return storage.get();
}
llvm::Error LoadedExecutablePlugin::spawnIfNeeded() {
if (Process) {
// See if the loaded one is still usable.
if (!Process->isStale)
return llvm::Error::success();
// NOTE: We don't check the mtime here because 'stat(2)' call is too heavy.
// PluginRegistry::loadExecutablePlugin() checks it and replace this object
// itself if the plugin is updated.
// The plugin is stale. Discard the previously opened process.
Process.reset();
}
// Create command line arguments.
SmallVector<StringRef, 4> command{ExecutablePath};
// Apply sandboxing.
llvm::BumpPtrAllocator Allocator;
if (!disableSandbox) {
Sandbox::apply(command, Allocator);
}
// Launch.
auto childInfo = ExecuteWithPipe(command[0], command);
if (!childInfo) {
return llvm::errorCodeToError(childInfo.getError());
}
Process = std::make_unique<PluginProcess>(childInfo->ProcessInfo,
childInfo->Read, childInfo->Write);
// Call "on reconnect" callbacks.
for (auto *callback : onReconnect) {
(*callback)();
}
return llvm::Error::success();
}
LoadedExecutablePlugin::PluginProcess::~PluginProcess() {
#if defined(_WIN32)
_close(input);
_close(output);
#else
close(input);
close(output);
#endif
llvm::sys::Wait(process, /*SecondsToWait=*/0);
}
LoadedExecutablePlugin::~LoadedExecutablePlugin() {
// Let ASTGen to cleanup things.
if (this->cleanup)
this->cleanup();
}
ssize_t LoadedExecutablePlugin::PluginProcess::read(void *buf,
size_t nbyte) const {
#if defined(_WIN32)
size_t nread = 0;
while (nread < nbyte) {
int n = _read(input, static_cast<char*>(buf) + nread,
std::min(static_cast<size_t>(UINT32_MAX), nbyte - nread));
if (n <= 0)
break;
nread += n;
}
return nread;
#else
ssize_t bytesToRead = nbyte;
void *ptr = buf;
#if defined(SIGPIPE)
/// Ignore SIGPIPE while reading.
auto *old_handler = signal(SIGPIPE, SIG_IGN);
SWIFT_DEFER { signal(SIGPIPE, old_handler); };
#endif
while (bytesToRead > 0) {
ssize_t readingSize = std::min(ssize_t(INT32_MAX), bytesToRead);
ssize_t readSize = ::read(input, ptr, readingSize);
if (readSize <= 0) {
// 0: EOF (the plugin exited?), -1: error (e.g. broken pipe.)
// FIXME: Mark the plugin 'stale' and relaunch later.
break;
}
ptr = static_cast<char *>(ptr) + readSize;
bytesToRead -= readSize;
}
return nbyte - bytesToRead;
#endif
}
ssize_t LoadedExecutablePlugin::PluginProcess::write(const void *buf,
size_t nbyte) const {
#if defined(_WIN32)
size_t nwritten = 0;
while (nwritten < nbyte) {
int n = _write(output, static_cast<const char *>(buf) + nwritten,
std::min(static_cast<size_t>(UINT32_MAX), nbyte - nwritten));
if (n <= 0)
break;
nwritten += n;
}
return nwritten;
#else
ssize_t bytesToWrite = nbyte;
const void *ptr = buf;
#if defined(SIGPIPE)
/// Ignore SIGPIPE while writing.
auto *old_handler = signal(SIGPIPE, SIG_IGN);
SWIFT_DEFER { signal(SIGPIPE, old_handler); };
#endif
while (bytesToWrite > 0) {
ssize_t writingSize = std::min(ssize_t(INT32_MAX), bytesToWrite);
ssize_t writtenSize = ::write(output, ptr, writingSize);
if (writtenSize <= 0) {
// -1: error (e.g. broken pipe,)
// FIXME: Mark the plugin 'stale' and relaunch later.
break;
}
ptr = static_cast<const char *>(ptr) + writtenSize;
bytesToWrite -= writtenSize;
}
return nbyte - bytesToWrite;
#endif
}
llvm::Error LoadedExecutablePlugin::sendMessage(llvm::StringRef message) const {
ssize_t writtenSize = 0;
if (dumpMessaging) {
llvm::dbgs() << "->(plugin:" << Process->process.Pid << ") " << message << '\n';
}
const char *data = message.data();
size_t size = message.size();
// Write header (message size).
uint64_t header = llvm::support::endian::byte_swap(uint64_t(size),
llvm::endianness::little);
writtenSize = Process->write(&header, sizeof(header));
if (writtenSize != sizeof(header)) {
setStale();
return llvm::createStringError(llvm::inconvertibleErrorCode(),
"failed to write plugin message header");
}
// Write message.
writtenSize = Process->write(data, size);
if (writtenSize != ssize_t(size)) {
setStale();
return llvm::createStringError(llvm::inconvertibleErrorCode(),
"failed to write plugin message data");
}
return llvm::Error::success();
}
llvm::Expected<std::string> LoadedExecutablePlugin::waitForNextMessage() const {
ssize_t readSize = 0;
// Read header (message size).
uint64_t header;
readSize = Process->read(&header, sizeof(header));
if (readSize != sizeof(header)) {
setStale();
return llvm::createStringError(llvm::inconvertibleErrorCode(),
"failed to read plugin message header");
}
size_t size =
llvm::support::endian::read<uint64_t>(&header, llvm::endianness::little);
// Read message.
std::string message;
message.reserve(size);
auto sizeToRead = size;
while (sizeToRead > 0) {
char buffer[4096];
readSize = Process->read(buffer, std::min(sizeof(buffer), sizeToRead));
if (readSize == 0) {
setStale();
return llvm::createStringError(llvm::inconvertibleErrorCode(),
"failed to read plugin message data");
}
sizeToRead -= readSize;
message.append(buffer, readSize);
}
if (dumpMessaging) {
llvm::dbgs() << "<-(plugin:" << Process->process.Pid << ") " << message << "\n";
}
return message;
}