blob: 204c67bc470ff4c8bb37415f13dcb89754621477 [file] [log] [blame]
//===-- lldb-gdbserver.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>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifndef _WIN32
#include <signal.h>
#include <unistd.h>
#endif
#include "Acceptor.h"
#include "LLDBServerUtilities.h"
#include "Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.h"
#include "Plugins/Process/gdb-remote/ProcessGDBRemoteLog.h"
#include "lldb/Host/ConnectionFileDescriptor.h"
#include "lldb/Host/FileSystem.h"
#include "lldb/Host/HostGetOpt.h"
#include "lldb/Host/OptionParser.h"
#include "lldb/Host/Pipe.h"
#include "lldb/Host/Socket.h"
#include "lldb/Host/StringConvert.h"
#include "lldb/Host/common/NativeProcessProtocol.h"
#include "lldb/Target/Process.h"
#include "lldb/Utility/Status.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/Errno.h"
#if defined(__linux__)
#include "Plugins/Process/Linux/NativeProcessLinux.h"
#elif defined(__NetBSD__)
#include "Plugins/Process/NetBSD/NativeProcessNetBSD.h"
#elif defined(_WIN32)
#include "Plugins/Process/Windows/Common/NativeProcessWindows.h"
#endif
#ifndef LLGS_PROGRAM_NAME
#define LLGS_PROGRAM_NAME "lldb-server"
#endif
#ifndef LLGS_VERSION_STR
#define LLGS_VERSION_STR "local_build"
#endif
using namespace llvm;
using namespace lldb;
using namespace lldb_private;
using namespace lldb_private::lldb_server;
using namespace lldb_private::process_gdb_remote;
namespace {
#if defined(__linux__)
typedef process_linux::NativeProcessLinux::Factory NativeProcessFactory;
#elif defined(__NetBSD__)
typedef process_netbsd::NativeProcessNetBSD::Factory NativeProcessFactory;
#elif defined(_WIN32)
typedef NativeProcessWindows::Factory NativeProcessFactory;
#else
// Dummy implementation to make sure the code compiles
class NativeProcessFactory : public NativeProcessProtocol::Factory {
public:
llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
Launch(ProcessLaunchInfo &launch_info,
NativeProcessProtocol::NativeDelegate &delegate,
MainLoop &mainloop) const override {
llvm_unreachable("Not implemented");
}
llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
Attach(lldb::pid_t pid, NativeProcessProtocol::NativeDelegate &delegate,
MainLoop &mainloop) const override {
llvm_unreachable("Not implemented");
}
};
#endif
}
// option descriptors for getopt_long_only()
static int g_debug = 0;
static int g_verbose = 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'},
{"attach", required_argument, nullptr, 'a'},
{"named-pipe", required_argument, nullptr, 'N'},
{"pipe", required_argument, nullptr, 'U'},
{"native-regs", no_argument, nullptr,
'r'}, // Specify to use the native registers instead of the gdb defaults
// for the architecture. NOTE: this is a do-nothing arg as it's
// behavior is default now. FIXME remove call from lldb-platform.
{"reverse-connect", no_argument, nullptr,
'R'}, // Specifies that llgs attaches to the client address:port rather
// than llgs listening for a connection from address on port.
{"setsid", no_argument, nullptr,
'S'}, // Call setsid() to make llgs run in its own session.
{"fd", required_argument, nullptr, 'F'},
{nullptr, 0, nullptr, 0}};
#ifndef _WIN32
// Watch for signals
static int g_sighup_received_count = 0;
static void sighup_handler(MainLoopBase &mainloop) {
++g_sighup_received_count;
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PROCESS));
LLDB_LOGF(log, "lldb-server:%s swallowing SIGHUP (receive count=%d)",
__FUNCTION__, g_sighup_received_count);
if (g_sighup_received_count >= 2)
mainloop.RequestTermination();
}
#endif // #ifndef _WIN32
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] "
"[--setsid] "
"[--fd file-descriptor]"
"[--named-pipe named-pipe-path] "
"[--native-regs] "
"[--attach pid] "
"[[HOST]:PORT] "
"[-- PROGRAM ARG1 ARG2 ...]\n",
progname, subcommand);
}
void handle_attach_to_pid(GDBRemoteCommunicationServerLLGS &gdb_server,
lldb::pid_t pid) {
Status error = gdb_server.AttachToProcess(pid);
if (error.Fail()) {
fprintf(stderr, "error: failed to attach to pid %" PRIu64 ": %s\n", pid,
error.AsCString());
exit(1);
}
}
void handle_attach_to_process_name(GDBRemoteCommunicationServerLLGS &gdb_server,
const std::string &process_name) {
// FIXME implement.
}
void handle_attach(GDBRemoteCommunicationServerLLGS &gdb_server,
const std::string &attach_target) {
assert(!attach_target.empty() && "attach_target cannot be empty");
// First check if the attach_target is convertible to a long. If so, we'll use
// it as a pid.
char *end_p = nullptr;
const long int pid = strtol(attach_target.c_str(), &end_p, 10);
// We'll call it a match if the entire argument is consumed.
if (end_p &&
static_cast<size_t>(end_p - attach_target.c_str()) ==
attach_target.size())
handle_attach_to_pid(gdb_server, static_cast<lldb::pid_t>(pid));
else
handle_attach_to_process_name(gdb_server, attach_target);
}
void handle_launch(GDBRemoteCommunicationServerLLGS &gdb_server, int argc,
const char *const argv[]) {
ProcessLaunchInfo info;
info.GetFlags().Set(eLaunchFlagStopAtEntry | eLaunchFlagDebug |
eLaunchFlagDisableASLR);
info.SetArguments(const_cast<const char **>(argv), true);
llvm::SmallString<64> cwd;
if (std::error_code ec = llvm::sys::fs::current_path(cwd)) {
llvm::errs() << "Error getting current directory: " << ec.message() << "\n";
exit(1);
}
FileSpec cwd_spec(cwd);
FileSystem::Instance().Resolve(cwd_spec);
info.SetWorkingDirectory(cwd_spec);
info.GetEnvironment() = Host::GetEnvironment();
gdb_server.SetLaunchInfo(info);
Status error = gdb_server.LaunchProcess();
if (error.Fail()) {
llvm::errs() << llvm::formatv("error: failed to launch '{0}': {1}\n",
argv[0], error);
exit(1);
}
}
Status writeSocketIdToPipe(Pipe &port_pipe, const std::string &socket_id) {
size_t bytes_written = 0;
// Write the port number as a C string with the NULL terminator.
return port_pipe.Write(socket_id.c_str(), socket_id.size() + 1,
bytes_written);
}
Status writeSocketIdToPipe(const char *const named_pipe_path,
const std::string &socket_id) {
Pipe port_name_pipe;
// Wait for 10 seconds for pipe to be opened.
auto error = port_name_pipe.OpenAsWriterWithTimeout(named_pipe_path, false,
std::chrono::seconds{10});
if (error.Fail())
return error;
return writeSocketIdToPipe(port_name_pipe, socket_id);
}
Status writeSocketIdToPipe(lldb::pipe_t unnamed_pipe,
const std::string &socket_id) {
Pipe port_pipe{LLDB_INVALID_PIPE, unnamed_pipe};
return writeSocketIdToPipe(port_pipe, socket_id);
}
void ConnectToRemote(MainLoop &mainloop,
GDBRemoteCommunicationServerLLGS &gdb_server,
bool reverse_connect, const char *const host_and_port,
const char *const progname, const char *const subcommand,
const char *const named_pipe_path, pipe_t unnamed_pipe,
int connection_fd) {
Status error;
std::unique_ptr<Connection> connection_up;
if (connection_fd != -1) {
// Build the connection string.
char connection_url[512];
snprintf(connection_url, sizeof(connection_url), "fd://%d", connection_fd);
// Create the connection.
#if !defined LLDB_DISABLE_POSIX && !defined _WIN32
::fcntl(connection_fd, F_SETFD, FD_CLOEXEC);
#endif
connection_up.reset(new ConnectionFileDescriptor);
auto connection_result = connection_up->Connect(connection_url, &error);
if (connection_result != eConnectionStatusSuccess) {
fprintf(stderr, "error: failed to connect to client at '%s' "
"(connection status: %d)\n",
connection_url, static_cast<int>(connection_result));
exit(-1);
}
if (error.Fail()) {
fprintf(stderr, "error: failed to connect to client at '%s': %s\n",
connection_url, error.AsCString());
exit(-1);
}
} else if (host_and_port && host_and_port[0]) {
// Parse out host and port.
std::string final_host_and_port;
std::string connection_host;
std::string connection_port;
uint32_t connection_portno = 0;
// If host_and_port starts with ':', default the host to be "localhost" and
// expect the remainder to be the port.
if (host_and_port[0] == ':')
final_host_and_port.append("localhost");
final_host_and_port.append(host_and_port);
const std::string::size_type colon_pos = final_host_and_port.find(':');
if (colon_pos != std::string::npos) {
connection_host = final_host_and_port.substr(0, colon_pos);
connection_port = final_host_and_port.substr(colon_pos + 1);
connection_portno = StringConvert::ToUInt32(connection_port.c_str(), 0);
}
if (reverse_connect) {
// llgs will connect to the gdb-remote client.
// Ensure we have a port number for the connection.
if (connection_portno == 0) {
fprintf(stderr, "error: port number must be specified on when using "
"reverse connect\n");
exit(1);
}
// Build the connection string.
char connection_url[512];
snprintf(connection_url, sizeof(connection_url), "connect://%s",
final_host_and_port.c_str());
// Create the connection.
connection_up.reset(new ConnectionFileDescriptor);
auto connection_result = connection_up->Connect(connection_url, &error);
if (connection_result != eConnectionStatusSuccess) {
fprintf(stderr, "error: failed to connect to client at '%s' "
"(connection status: %d)\n",
connection_url, static_cast<int>(connection_result));
exit(-1);
}
if (error.Fail()) {
fprintf(stderr, "error: failed to connect to client at '%s': %s\n",
connection_url, error.AsCString());
exit(-1);
}
} else {
std::unique_ptr<Acceptor> acceptor_up(
Acceptor::Create(final_host_and_port, false, error));
if (error.Fail()) {
fprintf(stderr, "failed to create acceptor: %s\n", error.AsCString());
exit(1);
}
error = acceptor_up->Listen(1);
if (error.Fail()) {
fprintf(stderr, "failed to listen: %s\n", error.AsCString());
exit(1);
}
const std::string socket_id = acceptor_up->GetLocalSocketId();
if (!socket_id.empty()) {
// If we have a named pipe to write the socket id back to, do that now.
if (named_pipe_path && named_pipe_path[0]) {
error = writeSocketIdToPipe(named_pipe_path, socket_id);
if (error.Fail())
fprintf(stderr, "failed to write to the named pipe \'%s\': %s\n",
named_pipe_path, error.AsCString());
}
// If we have an unnamed pipe to write the socket id back to, do that
// now.
else if (unnamed_pipe != LLDB_INVALID_PIPE) {
error = writeSocketIdToPipe(unnamed_pipe, socket_id);
if (error.Fail())
fprintf(stderr, "failed to write to the unnamed pipe: %s\n",
error.AsCString());
}
} else {
fprintf(stderr,
"unable to get the socket id for the listening connection\n");
}
Connection *conn = nullptr;
error = acceptor_up->Accept(false, conn);
if (error.Fail()) {
printf("failed to accept new connection: %s\n", error.AsCString());
exit(1);
}
connection_up.reset(conn);
}
}
error = gdb_server.InitializeConnection(std::move(connection_up));
if (error.Fail()) {
fprintf(stderr, "Failed to initialize connection: %s\n",
error.AsCString());
exit(-1);
}
printf("Connection established.\n");
}
// main
int main_gdbserver(int argc, char *argv[]) {
Status error;
MainLoop mainloop;
#ifndef _WIN32
// Setup signal handlers first thing.
signal(SIGPIPE, SIG_IGN);
MainLoop::SignalHandleUP sighup_handle =
mainloop.RegisterSignal(SIGHUP, sighup_handler, error);
#endif
const char *progname = argv[0];
const char *subcommand = argv[1];
argc--;
argv++;
int long_option_index = 0;
int ch;
std::string attach_target;
std::string named_pipe_path;
std::string log_file;
StringRef
log_channels; // e.g. "lldb process threads:gdb-remote default:linux all"
lldb::pipe_t unnamed_pipe = LLDB_INVALID_PIPE;
bool reverse_connect = false;
int connection_fd = -1;
// ProcessLaunchInfo launch_info;
ProcessAttachInfo attach_info;
bool show_usage = false;
int option_error = 0;
#if __GLIBC__
optind = 0;
#else
optreset = 1;
optind = 1;
#endif
std::string short_options(OptionParser::GetShortOptionString(g_long_options));
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': // 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 'N': // named pipe
if (optarg && optarg[0])
named_pipe_path = optarg;
break;
case 'U': // unnamed pipe
if (optarg && optarg[0])
unnamed_pipe = (pipe_t)StringConvert::ToUInt64(optarg, -1);
break;
case 'r':
// Do nothing, native regs is the default these days
break;
case 'R':
reverse_connect = true;
break;
case 'F':
connection_fd = StringConvert::ToUInt32(optarg, -1);
break;
#ifndef _WIN32
case 'S':
// Put llgs into a new session. Terminals group processes
// into sessions and when a special terminal key sequences
// (like control+c) are typed they can cause signals to go out to
// all processes in a session. Using this --setsid (-S) option
// will cause debugserver to run in its own sessions and be free
// from such issues.
//
// This is useful when llgs is spawned from a command
// line application that uses llgs to do the debugging,
// yet that application doesn't want llgs receiving the
// signals sent to the session (i.e. dying when anyone hits ^C).
{
const ::pid_t new_sid = setsid();
if (new_sid == -1) {
llvm::errs() << llvm::formatv(
"failed to set new session id for {0} ({1})\n", LLGS_PROGRAM_NAME,
llvm::sys::StrError());
}
}
break;
#endif
case 'a': // attach {pid|process_name}
if (optarg && optarg[0])
attach_target = optarg;
break;
case 'h': /* fall-through is intentional */
case '?':
show_usage = true;
break;
}
}
if (show_usage || option_error) {
display_usage(progname, subcommand);
exit(option_error);
}
if (!LLDBServerUtilities::SetupLogging(
log_file, log_channels,
LLDB_LOG_OPTION_PREPEND_TIMESTAMP |
LLDB_LOG_OPTION_PREPEND_FILE_FUNCTION))
return -1;
Log *log(lldb_private::GetLogIfAnyCategoriesSet(GDBR_LOG_PROCESS));
if (log) {
LLDB_LOGF(log, "lldb-server launch");
for (int i = 0; i < argc; i++) {
LLDB_LOGF(log, "argv[%i] = '%s'", i, argv[i]);
}
}
// Skip any options we consumed with getopt_long_only.
argc -= optind;
argv += optind;
if (argc == 0 && connection_fd == -1) {
fputs("No arguments\n", stderr);
display_usage(progname, subcommand);
exit(255);
}
NativeProcessFactory factory;
GDBRemoteCommunicationServerLLGS gdb_server(mainloop, factory);
const char *const host_and_port = argv[0];
argc -= 1;
argv += 1;
// Any arguments left over are for the program that we need to launch. If
// there
// are no arguments, then the GDB server will start up and wait for an 'A'
// packet
// to launch a program, or a vAttach packet to attach to an existing process,
// unless
// explicitly asked to attach with the --attach={pid|program_name} form.
if (!attach_target.empty())
handle_attach(gdb_server, attach_target);
else if (argc > 0)
handle_launch(gdb_server, argc, argv);
// Print version info.
printf("%s-%s\n", LLGS_PROGRAM_NAME, LLGS_VERSION_STR);
ConnectToRemote(mainloop, gdb_server, reverse_connect, host_and_port,
progname, subcommand, named_pipe_path.c_str(),
unnamed_pipe, connection_fd);
if (!gdb_server.IsConnected()) {
fprintf(stderr, "no connection information provided, unable to run\n");
display_usage(progname, subcommand);
return 1;
}
Status ret = mainloop.Run();
if (ret.Fail()) {
fprintf(stderr, "lldb-server terminating due to error: %s\n",
ret.AsCString());
return 1;
}
fprintf(stderr, "lldb-server exiting...\n");
return 0;
}