llvm-project/lldb/tools/lldb-server/lldb-platform.cpp

387 lines
12 KiB
C++

//===-- lldb-platform.cpp ---------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include <errno.h>
#if defined(__APPLE__)
#include <netinet/in.h>
#endif
#include <signal.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#if !defined(_WIN32)
#include <sys/wait.h>
#endif
#include <fstream>
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/FileUtilities.h"
#include "llvm/Support/raw_ostream.h"
#include "Acceptor.h"
#include "LLDBServerUtilities.h"
#include "Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.h"
#include "Plugins/Process/gdb-remote/ProcessGDBRemoteLog.h"
#include "lldb/Host/ConnectionFileDescriptor.h"
#include "lldb/Host/HostGetOpt.h"
#include "lldb/Host/OptionParser.h"
#include "lldb/Host/common/TCPSocket.h"
#include "lldb/Utility/FileSpec.h"
#include "lldb/Utility/Status.h"
using namespace lldb;
using namespace lldb_private;
using namespace lldb_private::lldb_server;
using namespace lldb_private::process_gdb_remote;
using namespace llvm;
// option descriptors for getopt_long_only()
static int g_debug = 0;
static int g_verbose = 0;
static int g_server = 0;
static struct option g_long_options[] = {
{"debug", no_argument, &g_debug, 1},
{"verbose", no_argument, &g_verbose, 1},
{"log-file", required_argument, nullptr, 'l'},
{"log-channels", required_argument, nullptr, 'c'},
{"listen", required_argument, nullptr, 'L'},
{"port-offset", required_argument, nullptr, 'p'},
{"gdbserver-port", required_argument, nullptr, 'P'},
{"min-gdbserver-port", required_argument, nullptr, 'm'},
{"max-gdbserver-port", required_argument, nullptr, 'M'},
{"socket-file", required_argument, nullptr, 'f'},
{"server", no_argument, &g_server, 1},
{nullptr, 0, nullptr, 0}};
#if defined(__APPLE__)
#define LOW_PORT (IPPORT_RESERVED)
#define HIGH_PORT (IPPORT_HIFIRSTAUTO)
#else
#define LOW_PORT (1024u)
#define HIGH_PORT (49151u)
#endif
#if !defined(_WIN32)
// Watch for signals
static void signal_handler(int signo) {
switch (signo) {
case SIGHUP:
// Use SIGINT first, if that does not work, use SIGHUP as a last resort.
// And we should not call exit() here because it results in the global
// destructors
// to be invoked and wreaking havoc on the threads still running.
Host::SystemLog(Host::eSystemLogWarning,
"SIGHUP received, exiting lldb-server...\n");
abort();
break;
}
}
#endif
static void display_usage(const char *progname, const char *subcommand) {
fprintf(stderr, "Usage:\n %s %s [--log-file log-file-name] [--log-channels "
"log-channel-list] [--port-file port-file-path] --server "
"--listen port\n",
progname, subcommand);
exit(0);
}
static Status save_socket_id_to_file(const std::string &socket_id,
const FileSpec &file_spec) {
FileSpec temp_file_spec(file_spec.GetDirectory().GetStringRef());
Status error(llvm::sys::fs::create_directory(temp_file_spec.GetPath()));
if (error.Fail())
return Status("Failed to create directory %s: %s",
temp_file_spec.GetCString(), error.AsCString());
llvm::SmallString<64> temp_file_path;
temp_file_spec.AppendPathComponent("port-file.%%%%%%");
temp_file_path = temp_file_spec.GetPath();
Status status;
if (auto Err =
handleErrors(llvm::writeFileAtomically(
temp_file_path, file_spec.GetPath(), socket_id),
[&status, &file_spec](const AtomicFileWriteError &E) {
std::string ErrorMsgBuffer;
llvm::raw_string_ostream S(ErrorMsgBuffer);
E.log(S);
switch (E.Error) {
case atomic_write_error::failed_to_create_uniq_file:
status = Status("Failed to create temp file: %s",
ErrorMsgBuffer.c_str());
break;
case atomic_write_error::output_stream_error:
status = Status("Failed to write to port file.");
break;
case atomic_write_error::failed_to_rename_temp_file:
status = Status("Failed to rename file %s to %s: %s",
ErrorMsgBuffer.c_str(),
file_spec.GetPath().c_str(),
ErrorMsgBuffer.c_str());
break;
}
})) {
return Status("Failed to atomically write file %s",
file_spec.GetPath().c_str());
}
return status;
}
// main
int main_platform(int argc, char *argv[]) {
const char *progname = argv[0];
const char *subcommand = argv[1];
argc--;
argv++;
#if !defined(_WIN32)
signal(SIGPIPE, SIG_IGN);
signal(SIGHUP, signal_handler);
#endif
int long_option_index = 0;
Status error;
std::string listen_host_port;
int ch;
std::string log_file;
StringRef
log_channels; // e.g. "lldb process threads:gdb-remote default:linux all"
GDBRemoteCommunicationServerPlatform::PortMap gdbserver_portmap;
int min_gdbserver_port = 0;
int max_gdbserver_port = 0;
uint16_t port_offset = 0;
FileSpec socket_file;
bool show_usage = false;
int option_error = 0;
int socket_error = -1;
std::string short_options(OptionParser::GetShortOptionString(g_long_options));
#if __GLIBC__
optind = 0;
#else
optreset = 1;
optind = 1;
#endif
while ((ch = getopt_long_only(argc, argv, short_options.c_str(),
g_long_options, &long_option_index)) != -1) {
switch (ch) {
case 0: // Any optional that auto set themselves will return 0
break;
case 'L':
listen_host_port.append(optarg);
break;
case 'l': // Set Log File
if (optarg && optarg[0])
log_file.assign(optarg);
break;
case 'c': // Log Channels
if (optarg && optarg[0])
log_channels = StringRef(optarg);
break;
case 'f': // Socket file
if (optarg && optarg[0])
socket_file.SetFile(optarg, FileSpec::Style::native);
break;
case 'p': {
if (!llvm::to_integer(optarg, port_offset)) {
llvm::errs() << "error: invalid port offset string " << optarg << "\n";
option_error = 4;
break;
}
if (port_offset < LOW_PORT || port_offset > HIGH_PORT) {
llvm::errs() << llvm::formatv("error: port offset {0} is not in the "
"valid user port range of {1} - {2}\n",
port_offset, LOW_PORT, HIGH_PORT);
option_error = 5;
}
} break;
case 'P':
case 'm':
case 'M': {
uint16_t portnum;
if (!llvm::to_integer(optarg, portnum)) {
llvm::errs() << "error: invalid port number string " << optarg << "\n";
option_error = 2;
break;
}
if (portnum < LOW_PORT || portnum > HIGH_PORT) {
llvm::errs() << llvm::formatv("error: port number {0} is not in the "
"valid user port range of {1} - {2}\n",
portnum, LOW_PORT, HIGH_PORT);
option_error = 1;
break;
}
if (ch == 'P')
gdbserver_portmap[portnum] = LLDB_INVALID_PROCESS_ID;
else if (ch == 'm')
min_gdbserver_port = portnum;
else
max_gdbserver_port = portnum;
} break;
case 'h': /* fall-through is intentional */
case '?':
show_usage = true;
break;
}
}
if (!LLDBServerUtilities::SetupLogging(log_file, log_channels, 0))
return -1;
// Make a port map for a port range that was specified.
if (min_gdbserver_port && min_gdbserver_port < max_gdbserver_port) {
for (uint16_t port = min_gdbserver_port; port < max_gdbserver_port; ++port)
gdbserver_portmap[port] = LLDB_INVALID_PROCESS_ID;
} else if (min_gdbserver_port || max_gdbserver_port) {
fprintf(stderr, "error: --min-gdbserver-port (%u) is not lower than "
"--max-gdbserver-port (%u)\n",
min_gdbserver_port, max_gdbserver_port);
option_error = 3;
}
// Print usage and exit if no listening port is specified.
if (listen_host_port.empty())
show_usage = true;
if (show_usage || option_error) {
display_usage(progname, subcommand);
exit(option_error);
}
// Skip any options we consumed with getopt_long_only.
argc -= optind;
argv += optind;
lldb_private::Args inferior_arguments;
inferior_arguments.SetArguments(argc, const_cast<const char **>(argv));
const bool children_inherit_listen_socket = false;
// the test suite makes many connections in parallel, let's not miss any.
// The highest this should get reasonably is a function of the number
// of target CPUs. For now, let's just use 100.
const int backlog = 100;
std::unique_ptr<Acceptor> acceptor_up(Acceptor::Create(
listen_host_port, children_inherit_listen_socket, error));
if (error.Fail()) {
fprintf(stderr, "failed to create acceptor: %s", error.AsCString());
exit(socket_error);
}
error = acceptor_up->Listen(backlog);
if (error.Fail()) {
printf("failed to listen: %s\n", error.AsCString());
exit(socket_error);
}
if (socket_file) {
error =
save_socket_id_to_file(acceptor_up->GetLocalSocketId(), socket_file);
if (error.Fail()) {
fprintf(stderr, "failed to write socket id to %s: %s\n",
socket_file.GetPath().c_str(), error.AsCString());
return 1;
}
}
do {
GDBRemoteCommunicationServerPlatform platform(
acceptor_up->GetSocketProtocol(), acceptor_up->GetSocketScheme());
if (port_offset > 0)
platform.SetPortOffset(port_offset);
if (!gdbserver_portmap.empty()) {
platform.SetPortMap(std::move(gdbserver_portmap));
}
const bool children_inherit_accept_socket = true;
Connection *conn = nullptr;
error = acceptor_up->Accept(children_inherit_accept_socket, conn);
if (error.Fail()) {
printf("error: %s\n", error.AsCString());
exit(socket_error);
}
printf("Connection established.\n");
if (g_server) {
// Collect child zombie processes.
#if !defined(_WIN32)
while (waitpid(-1, nullptr, WNOHANG) > 0)
;
#endif
if (fork()) {
// Parent doesn't need a connection to the lldb client
delete conn;
// Parent will continue to listen for new connections.
continue;
} else {
// Child process will handle the connection and exit.
g_server = 0;
// Listening socket is owned by parent process.
acceptor_up.release();
}
} else {
// If not running as a server, this process will not accept
// connections while a connection is active.
acceptor_up.reset();
}
platform.SetConnection(std::unique_ptr<Connection>(conn));
if (platform.IsConnected()) {
if (inferior_arguments.GetArgumentCount() > 0) {
lldb::pid_t pid = LLDB_INVALID_PROCESS_ID;
uint16_t port = 0;
std::string socket_name;
Status error = platform.LaunchGDBServer(inferior_arguments,
"", // hostname
pid, port, socket_name);
if (error.Success())
platform.SetPendingGdbServer(pid, port, socket_name);
else
fprintf(stderr, "failed to start gdbserver: %s\n", error.AsCString());
}
// After we connected, we need to get an initial ack from...
if (platform.HandshakeWithClient()) {
bool interrupt = false;
bool done = false;
while (!interrupt && !done) {
if (platform.GetPacketAndSendResponse(llvm::None, error, interrupt,
done) !=
GDBRemoteCommunication::PacketResult::Success)
break;
}
if (error.Fail()) {
fprintf(stderr, "error: %s\n", error.AsCString());
}
} else {
fprintf(stderr, "error: handshake with client failed\n");
}
}
} while (g_server);
fprintf(stderr, "lldb-server exiting...\n");
return 0;
}