#include <atomic>
#include <cassert>
#include <chrono>
#include <cstdlib>
#include <cstring>
#include <errno.h>
#include <future>
#include <inttypes.h>
#include <memory>
#include <mutex>
#if !defined(_WIN32)
#include <pthread.h>
#include <signal.h>
#include <unistd.h>
#endif
#include "thread.h"
#include <setjmp.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <string>
#include <thread>
#include <time.h>
#include <vector>
#if defined(__APPLE__)
#include <TargetConditionals.h>
#endif
static const char *const PRINT_PID_COMMAND = "print-pid";
static bool g_print_thread_ids = false;
static std::mutex g_print_mutex;
static bool g_threads_do_segfault = false;
static std::mutex g_jump_buffer_mutex;
static jmp_buf g_jump_buffer;
static bool g_is_segfaulting = false;
static char g_message[256];
static volatile char g_c1 = '0';
static volatile char g_c2 = '1';
static void print_pid() {
#if defined(_WIN32)
fprintf(stderr, "PID: %d\n", ::GetCurrentProcessId());
#else
fprintf(stderr, "PID: %d\n", getpid());
#endif
}
static void signal_handler(int signo) {
#if defined(_WIN32)
// No signal support on Windows.
#else
const char *signal_name = nullptr;
switch (signo) {
case SIGUSR1:
signal_name = "SIGUSR1";
break;
case SIGSEGV:
signal_name = "SIGSEGV";
break;
default:
signal_name = nullptr;
}
// Print notice that we received the signal on a given thread.
char buf[100];
if (signal_name)
snprintf(buf, sizeof(buf), "received %s on thread id: %" PRIx64 "\n", signal_name, get_thread_id());
else
snprintf(buf, sizeof(buf), "received signo %d (%s) on thread id: %" PRIx64 "\n", signo, strsignal(signo), get_thread_id());
write(STDOUT_FILENO, buf, strlen(buf));
// Reset the signal handler if we're one of the expected signal handlers.
switch (signo) {
case SIGSEGV:
if (g_is_segfaulting) {
// Fix up the pointer we're writing to. This needs to happen if nothing
// intercepts the SIGSEGV (i.e. if somebody runs this from the command
// line).
longjmp(g_jump_buffer, 1);
}
break;
case SIGUSR1:
if (g_is_segfaulting) {
// Fix up the pointer we're writing to. This is used to test gdb remote
// signal delivery. A SIGSEGV will be raised when the thread is created,
// switched out for a SIGUSR1, and then this code still needs to fix the
// seg fault. (i.e. if somebody runs this from the command line).
longjmp(g_jump_buffer, 1);
}
break;
}
// Reset the signal handler.
sig_t sig_result = signal(signo, signal_handler);
if (sig_result == SIG_ERR) {
fprintf(stderr, "failed to set signal handler: errno=%d\n", errno);
exit(1);
}
#endif
}
static void swap_chars() {
#if defined(__x86_64__) || defined(__i386__)
asm volatile("movb %1, (%2)\n\t"
"movb %0, (%3)\n\t"
"movb %0, (%2)\n\t"
"movb %1, (%3)\n\t"
:
: "i"('0'), "i"('1'), "r"(&g_c1), "r"(&g_c2)
: "memory");
#elif defined(__aarch64__)
asm volatile("strb %w1, [%2]\n\t"
"strb %w0, [%3]\n\t"
"strb %w0, [%2]\n\t"
"strb %w1, [%3]\n\t"
:
: "r"('0'), "r"('1'), "r"(&g_c1), "r"(&g_c2)
: "memory");
#elif defined(__arm__)
asm volatile("strb %1, [%2]\n\t"
"strb %0, [%3]\n\t"
"strb %0, [%2]\n\t"
"strb %1, [%3]\n\t"
:
: "r"('0'), "r"('1'), "r"(&g_c1), "r"(&g_c2)
: "memory");
#else
#warning This may generate unpredictible assembly and cause the single-stepping test to fail.
#warning Please add appropriate assembly for your target.
g_c1 = '1';
g_c2 = '0';
g_c1 = '0';
g_c2 = '1';
#endif
}
static void trap() {
#if defined(__x86_64__) || defined(__i386__)
asm volatile("int3");
#elif defined(__aarch64__)
asm volatile("brk #0xf000");
#elif defined(__arm__)
asm volatile("udf #254");
#elif defined(__powerpc__)
asm volatile("trap");
#elif __has_builtin(__builtin_debugtrap())
__builtin_debugtrap();
#else
#warning Don't know how to generate a trap. Some tests may fail.
#endif
}
static void hello() {
std::lock_guard<std::mutex> lock(g_print_mutex);
printf("hello, world\n");
}
static void *thread_func(std::promise<void> ready) {
ready.set_value();
static std::atomic<int> s_thread_index(1);
const int this_thread_index = s_thread_index++;
if (g_print_thread_ids) {
std::lock_guard<std::mutex> lock(g_print_mutex);
printf("thread %d id: %" PRIx64 "\n", this_thread_index, get_thread_id());
}
if (g_threads_do_segfault) {
// Sleep for a number of seconds based on the thread index.
// TODO add ability to send commands to test exe so we can
// handle timing more precisely. This is clunky. All we're
// trying to do is add predictability as to the timing of
// signal generation by created threads.
int sleep_seconds = 2 * (this_thread_index - 1);
std::this_thread::sleep_for(std::chrono::seconds(sleep_seconds));
// Test creating a SEGV.
{
std::lock_guard<std::mutex> lock(g_jump_buffer_mutex);
g_is_segfaulting = true;
int *bad_p = nullptr;
if (setjmp(g_jump_buffer) == 0) {
// Force a seg fault signal on this thread.
*bad_p = 0;
} else {
// Tell the system we're no longer seg faulting.
// Used by the SIGUSR1 signal handler that we inject
// in place of the SIGSEGV so it only tries to
// recover from the SIGSEGV if this seg fault code
// was in play.
g_is_segfaulting = false;
}
}
{
std::lock_guard<std::mutex> lock(g_print_mutex);
printf("thread %" PRIx64 ": past SIGSEGV\n", get_thread_id());
}
}
int sleep_seconds_remaining = 60;
std::this_thread::sleep_for(std::chrono::seconds(sleep_seconds_remaining));
return nullptr;
}
static bool consume_front(std::string &str, const std::string &front) {
if (str.find(front) != 0)
return false;
str = str.substr(front.size());
return true;
}
int main(int argc, char **argv) {
lldb_enable_attach();
std::vector<std::thread> threads;
std::unique_ptr<uint8_t[]> heap_array_up;
int return_value = 0;
#if !defined(_WIN32)
bool is_child = false;
// Set the signal handler.
sig_t sig_result = signal(SIGALRM, signal_handler);
if (sig_result == SIG_ERR) {
fprintf(stderr, "failed to set SIGALRM signal handler: errno=%d\n", errno);
exit(1);
}
sig_result = signal(SIGUSR1, signal_handler);
if (sig_result == SIG_ERR) {
fprintf(stderr, "failed to set SIGUSR1 handler: errno=%d\n", errno);
exit(1);
}
sig_result = signal(SIGSEGV, signal_handler);
if (sig_result == SIG_ERR) {
fprintf(stderr, "failed to set SIGSEGV handler: errno=%d\n", errno);
exit(1);
}
sig_result = signal(SIGCHLD, SIG_IGN);
if (sig_result == SIG_ERR) {
fprintf(stderr, "failed to set SIGCHLD handler: errno=%d\n", errno);
exit(1);
}
#endif
// Process command line args.
for (int i = 1; i < argc; ++i) {
std::string arg = argv[i];
if (consume_front(arg, "stderr:")) {
// Treat remainder as text to go to stderr.
fprintf(stderr, "%s\n", arg.c_str());
} else if (consume_front(arg, "retval:")) {
// Treat as the return value for the program.
return_value = std::atoi(arg.c_str());
} else if (consume_front(arg, "sleep:")) {
// Treat as the amount of time to have this process sleep (in seconds).
int sleep_seconds_remaining = std::atoi(arg.c_str());
// Loop around, sleeping until all sleep time is used up. Note that
// signals will cause sleep to end early with the number of seconds
// remaining.
std::this_thread::sleep_for(
std::chrono::seconds(sleep_seconds_remaining));
} else if (consume_front(arg, "set-message:")) {
// Copy the contents after "set-message:" to the g_message buffer.
// Used for reading inferior memory and verifying contents match
// expectations.
strncpy(g_message, arg.c_str(), sizeof(g_message));
// Ensure we're null terminated.
g_message[sizeof(g_message) - 1] = '\0';
} else if (consume_front(arg, "print-message:")) {
std::lock_guard<std::mutex> lock(g_print_mutex);
printf("message: %s\n", g_message);
} else if (consume_front(arg, "get-data-address-hex:")) {
volatile void *data_p = nullptr;
if (arg == "g_message")
data_p = &g_message[0];
else if (arg == "g_c1")
data_p = &g_c1;
else if (arg == "g_c2")
data_p = &g_c2;
std::lock_guard<std::mutex> lock(g_print_mutex);
printf("data address: %p\n", data_p);
} else if (consume_front(arg, "get-heap-address-hex:")) {
// Create a byte array if not already present.
if (!heap_array_up)
heap_array_up.reset(new uint8_t[32]);
std::lock_guard<std::mutex> lock(g_print_mutex);
printf("heap address: %p\n", heap_array_up.get());
} else if (consume_front(arg, "get-stack-address-hex:")) {
std::lock_guard<std::mutex> lock(g_print_mutex);
printf("stack address: %p\n", &return_value);
} else if (consume_front(arg, "get-code-address-hex:")) {
void (*func_p)() = nullptr;
if (arg == "hello")
func_p = hello;
else if (arg == "swap_chars")
func_p = swap_chars;
std::lock_guard<std::mutex> lock(g_print_mutex);
printf("code address: %p\n", func_p);
} else if (consume_front(arg, "call-function:")) {
void (*func_p)() = nullptr;
if (arg == "hello")
func_p = hello;
else if (arg == "swap_chars")
func_p = swap_chars;
func_p();
#if !defined(_WIN32) && !defined(TARGET_OS_WATCH) && !defined(TARGET_OS_TV)
} else if (arg == "fork") {
pid_t fork_pid = fork();
assert(fork_pid != -1);
is_child = fork_pid == 0;
} else if (arg == "vfork") {
if (vfork() == 0)
_exit(0);
} else if (consume_front(arg, "process:sync:")) {
// this is only valid after fork
const char *filenames[] = {"parent", "child"};
std::string my_file = arg + "." + filenames[is_child];
std::string other_file = arg + "." + filenames[!is_child];
// indicate that we're ready
FILE *f = fopen(my_file.c_str(), "w");
assert(f);
fclose(f);
// wait for the other process to be ready
for (int i = 0; i < 5; ++i) {
f = fopen(other_file.c_str(), "r");
if (f)
break;
std::this_thread::sleep_for(std::chrono::milliseconds(125 * (1<<i)));
}
assert(f);
fclose(f);
#endif
} else if (consume_front(arg, "thread:new")) {
std::promise<void> promise;
std::future<void> ready = promise.get_future();
threads.push_back(std::thread(thread_func, std::move(promise)));
ready.wait();
} else if (consume_front(arg, "thread:print-ids")) {
// Turn on thread id announcing.
g_print_thread_ids = true;
// And announce us.
{
std::lock_guard<std::mutex> lock(g_print_mutex);
printf("thread 0 id: %" PRIx64 "\n", get_thread_id());
}
} else if (consume_front(arg, "thread:segfault")) {
g_threads_do_segfault = true;
} else if (consume_front(arg, "print-pid")) {
print_pid();
} else if (consume_front(arg, "print-env:")) {
// Print the value of specified envvar to stdout.
const char *value = getenv(arg.c_str());
printf("%s\n", value ? value : "__unset__");
} else if (consume_front(arg, "trap")) {
trap();
#if !defined(_WIN32)
} else if (arg == "stop") {
raise(SIGINT);
#endif
} else {
// Treat the argument as text for stdout.
printf("%s\n", argv[i]);
}
}
// If we launched any threads, join them
for (std::vector<std::thread>::iterator it = threads.begin();
it != threads.end(); ++it)
it->join();
return return_value;
}
Codebase Browser
llvm