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

390 lines
13 KiB
C++

//===-- lldb-platform.cpp ---------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// C Includes
#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>
#include <sys/wait.h>
// C++ Includes
#include <fstream>
// Other libraries and framework includes
#include "lldb/Core/Error.h"
#include "lldb/Host/ConnectionFileDescriptor.h"
#include "lldb/Host/FileSpec.h"
#include "lldb/Host/FileSystem.h"
#include "lldb/Host/HostGetOpt.h"
#include "lldb/Host/OptionParser.h"
#include "lldb/Host/Socket.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/FileUtilities.h"
#include "LLDBServerUtilities.h"
#include "Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.h"
#include "Plugins/Process/gdb-remote/ProcessGDBRemoteLog.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, NULL, 'l' },
{ "log-channels", required_argument, NULL, 'c' },
{ "listen", required_argument, NULL, 'L' },
{ "port-offset", required_argument, NULL, 'p' },
{ "gdbserver-port", required_argument, NULL, 'P' },
{ "min-gdbserver-port", required_argument, NULL, 'm' },
{ "max-gdbserver-port", required_argument, NULL, 'M' },
{ "port-file", required_argument, NULL, 'f' },
{ "server", no_argument, &g_server, 1 },
{ NULL, 0, NULL, 0 }
};
#if defined (__APPLE__)
#define LOW_PORT (IPPORT_RESERVED)
#define HIGH_PORT (IPPORT_HIFIRSTAUTO)
#else
#define LOW_PORT (1024u)
#define HIGH_PORT (49151u)
#endif
//----------------------------------------------------------------------
// 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;
}
}
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 Error
save_port_to_file(const uint16_t port, const FileSpec &port_file_spec)
{
FileSpec temp_file_spec(port_file_spec.GetDirectory().AsCString(), false);
auto error = FileSystem::MakeDirectory(temp_file_spec, eFilePermissionsDirectoryDefault);
if (error.Fail())
return Error("Failed to create directory %s: %s", temp_file_spec.GetCString(), error.AsCString());
llvm::SmallString<PATH_MAX> temp_file_path;
temp_file_spec.AppendPathComponent("port-file.%%%%%%");
auto err_code = llvm::sys::fs::createUniqueFile(temp_file_spec.GetCString(), temp_file_path);
if (err_code)
return Error("Failed to create temp file: %s", err_code.message().c_str());
llvm::FileRemover tmp_file_remover(temp_file_path.c_str());
{
std::ofstream temp_file(temp_file_path.c_str(), std::ios::out);
if (!temp_file.is_open())
return Error("Failed to open temp file %s", temp_file_path.c_str());
temp_file << port;
}
err_code = llvm::sys::fs::rename(temp_file_path.c_str(), port_file_spec.GetPath().c_str());
if (err_code)
return Error("Failed to rename file %s to %s: %s",
temp_file_path.c_str(), port_file_spec.GetPath().c_str(), err_code.message().c_str());
tmp_file_remover.releaseFile();
return Error();
}
//----------------------------------------------------------------------
// main
//----------------------------------------------------------------------
int
main_platform (int argc, char *argv[])
{
const char *progname = argv[0];
const char *subcommand = argv[1];
argc--;
argv++;
signal (SIGPIPE, SIG_IGN);
signal (SIGHUP, signal_handler);
int long_option_index = 0;
Error 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 port_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': // Port file
if (optarg && optarg[0])
port_file.SetFile(optarg, false);
break;
case 'p':
{
char *end = NULL;
long tmp_port_offset = strtoul(optarg, &end, 0);
if (end && *end == '\0')
{
if (LOW_PORT <= tmp_port_offset && tmp_port_offset <= HIGH_PORT)
{
port_offset = (uint16_t)tmp_port_offset;
}
else
{
fprintf (stderr, "error: port offset %li is not in the valid user port range of %u - %u\n", tmp_port_offset, LOW_PORT, HIGH_PORT);
option_error = 5;
}
}
else
{
fprintf (stderr, "error: invalid port offset string %s\n", optarg);
option_error = 4;
}
}
break;
case 'P':
case 'm':
case 'M':
{
char *end = NULL;
long portnum = strtoul(optarg, &end, 0);
if (end && *end == '\0')
{
if (LOW_PORT <= portnum && portnum <= HIGH_PORT)
{
if (ch == 'P')
gdbserver_portmap[(uint16_t)portnum] = LLDB_INVALID_PROCESS_ID;
else if (ch == 'm')
min_gdbserver_port = portnum;
else
max_gdbserver_port = portnum;
}
else
{
fprintf (stderr, "error: port number %li is not in the valid user port range of %u - %u\n", portnum, LOW_PORT, HIGH_PORT);
option_error = 1;
}
}
else
{
fprintf (stderr, "error: invalid port number string %s\n", optarg);
option_error = 2;
}
}
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 < 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 greater 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);
}
std::unique_ptr<Socket> listening_socket_up;
Socket *socket = nullptr;
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;
error = Socket::TcpListen(listen_host_port.c_str(), children_inherit_listen_socket, socket, NULL, backlog);
if (error.Fail())
{
printf("error: %s\n", error.AsCString());
exit(socket_error);
}
listening_socket_up.reset(socket);
printf ("Listening for a connection from %u...\n", listening_socket_up->GetLocalPortNumber());
if (port_file)
{
error = save_port_to_file(listening_socket_up->GetLocalPortNumber(), port_file);
if (error.Fail())
{
fprintf(stderr, "failed to write port to %s: %s", port_file.GetPath().c_str(), error.AsCString());
return 1;
}
}
do {
GDBRemoteCommunicationServerPlatform platform;
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;
socket = nullptr;
error = listening_socket_up->BlockingAccept(listen_host_port.c_str(), children_inherit_accept_socket, socket);
if (error.Fail())
{
printf ("error: %s\n", error.AsCString());
exit(socket_error);
}
printf ("Connection established.\n");
if (g_server)
{
// Collect child zombie processes.
while (waitpid(-1, nullptr, WNOHANG) > 0);
if (fork())
{
// Parent doesn't need a connection to the lldb client
delete socket;
socket = nullptr;
// 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.
listening_socket_up.release();
}
}
else
{
// If not running as a server, this process will not accept
// connections while a connection is active.
listening_socket_up.reset();
}
platform.SetConnection (new ConnectionFileDescriptor(socket));
if (platform.IsConnected())
{
// 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 (UINT32_MAX, 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;
}