corda/src/posix.cpp
Joel Dice 349d381d95 progress towards cross-endian bootimage builds
This fixes a number of bugs concerning cross-architecture bootimage
builds involving diffent endianesses.  There will be more work to do
before it works.
2011-09-16 20:53:08 -06:00

1000 lines
22 KiB
C++

/* Copyright (c) 2008-2011, Avian Contributors
Permission to use, copy, modify, and/or distribute this software
for any purpose with or without fee is hereby granted, provided
that the above copyright notice and this permission notice appear
in all copies.
There is NO WARRANTY for this software. See license.txt for
details. */
#ifndef __STDC_CONSTANT_MACROS
# define __STDC_CONSTANT_MACROS
#endif
#ifdef __APPLE__
# include "CoreFoundation/CoreFoundation.h"
# undef assert
#endif
#include "sys/mman.h"
#include "sys/types.h"
#include "sys/stat.h"
#include "sys/time.h"
#include "time.h"
#include "fcntl.h"
#include "dlfcn.h"
#include "errno.h"
#include "unistd.h"
#include "pthread.h"
#include "signal.h"
#include "sys/ucontext.h"
#include "stdint.h"
#include "dirent.h"
#include "sched.h"
#include "arch.h"
#include "system.h"
#define ACQUIRE(x) MutexResource MAKE_NAME(mutexResource_) (x)
using namespace vm;
namespace {
class MutexResource {
public:
MutexResource(pthread_mutex_t& m): m(&m) {
pthread_mutex_lock(&m);
}
~MutexResource() {
pthread_mutex_unlock(m);
}
private:
pthread_mutex_t* m;
};
const int InvalidSignal = -1;
const int VisitSignal = SIGUSR1;
const unsigned VisitSignalIndex = 0;
const int SegFaultSignal = SIGSEGV;
const unsigned SegFaultSignalIndex = 1;
const int InterruptSignal = SIGUSR2;
const unsigned InterruptSignalIndex = 2;
#ifdef __APPLE__
const int AltSegFaultSignal = SIGBUS;
#else
const int AltSegFaultSignal = InvalidSignal;
#endif
const unsigned AltSegFaultSignalIndex = 3;
const int PipeSignal = SIGPIPE;
const unsigned PipeSignalIndex = 4;
const int DivideByZeroSignal = SIGFPE;
const unsigned DivideByZeroSignalIndex = 5;
const int signals[] = { VisitSignal,
SegFaultSignal,
InterruptSignal,
AltSegFaultSignal,
PipeSignal,
DivideByZeroSignal };
const unsigned SignalCount = 6;
class MySystem;
MySystem* system;
void
handleSignal(int signal, siginfo_t* info, void* context);
void*
run(void* r)
{
static_cast<System::Runnable*>(r)->run();
return 0;
}
void
pathOfExecutable(System* s, const char** retBuf, unsigned* size)
{
#ifdef __APPLE__
CFBundleRef bundle = CFBundleGetMainBundle();
CFURLRef url = CFBundleCopyExecutableURL(bundle);
CFStringRef path = CFURLCopyPath(url);
path = CFURLCreateStringByReplacingPercentEscapes(kCFAllocatorDefault,
path, CFSTR(""));
CFIndex pathSize = CFStringGetMaximumSizeOfFileSystemRepresentation(path);
char* buffer = reinterpret_cast<char*>(allocate(s, pathSize));
if (CFStringGetFileSystemRepresentation(path, buffer, pathSize)) {
*size = pathSize;
*retBuf = buffer;
} else {
abort();
}
#else
if (s)
*size = 0;
*retBuf = NULL;
#endif
}
const bool Verbose = false;
const unsigned Waiting = 1 << 0;
const unsigned Notified = 1 << 1;
class MySystem: public System {
public:
class Thread: public System::Thread {
public:
Thread(System* s, System::Runnable* r):
s(s),
r(r),
next(0),
flags(0)
{
pthread_mutex_init(&mutex, 0);
pthread_cond_init(&condition, 0);
}
virtual void interrupt() {
ACQUIRE(mutex);
r->setInterrupted(true);
pthread_kill(thread, InterruptSignal);
// pthread_kill won't necessarily wake a thread blocked in
// pthread_cond_{timed}wait (it does on Linux but not Mac OS),
// so we signal the condition as well:
int rv UNUSED = pthread_cond_signal(&condition);
expect(s, rv == 0);
}
virtual bool getAndClearInterrupted() {
ACQUIRE(mutex);
bool interrupted = r->interrupted();
r->setInterrupted(false);
return interrupted;
}
virtual void join() {
int rv UNUSED = pthread_join(thread, 0);
expect(s, rv == 0);
}
virtual void dispose() {
s->free(this);
}
pthread_t thread;
pthread_mutex_t mutex;
pthread_cond_t condition;
System* s;
System::Runnable* r;
Thread* next;
unsigned flags;
};
class Mutex: public System::Mutex {
public:
Mutex(System* s): s(s) {
pthread_mutex_init(&mutex, 0);
}
virtual void acquire() {
pthread_mutex_lock(&mutex);
}
virtual void release() {
pthread_mutex_unlock(&mutex);
}
virtual void dispose() {
pthread_mutex_destroy(&mutex);
s->free(this);
}
System* s;
pthread_mutex_t mutex;
};
class Monitor: public System::Monitor {
public:
Monitor(System* s): s(s), owner_(0), first(0), last(0), depth(0) {
pthread_mutex_init(&mutex, 0);
}
virtual bool tryAcquire(System::Thread* context) {
Thread* t = static_cast<Thread*>(context);
if (owner_ == t) {
++ depth;
return true;
} else {
switch (pthread_mutex_trylock(&mutex)) {
case EBUSY:
return false;
case 0:
owner_ = t;
++ depth;
return true;
default:
sysAbort(s);
}
}
}
virtual void acquire(System::Thread* context) {
Thread* t = static_cast<Thread*>(context);
if (owner_ != t) {
pthread_mutex_lock(&mutex);
owner_ = t;
}
++ depth;
}
virtual void release(System::Thread* context) {
Thread* t = static_cast<Thread*>(context);
if (owner_ == t) {
if (-- depth == 0) {
owner_ = 0;
pthread_mutex_unlock(&mutex);
}
} else {
sysAbort(s);
}
}
void append(Thread* t) {
if (last) {
last->next = t;
last = t;
} else {
first = last = t;
}
}
void remove(Thread* t) {
Thread* previous = 0;
for (Thread* current = first; current;) {
if (t == current) {
if (current == first) {
first = t->next;
} else {
previous->next = t->next;
}
if (current == last) {
last = previous;
}
t->next = 0;
break;
} else {
previous = current;
current = current->next;
}
}
}
virtual void wait(System::Thread* context, int64_t time) {
wait(context, time, false);
}
virtual bool waitAndClearInterrupted(System::Thread* context, int64_t time)
{
return wait(context, time, true);
}
bool wait(System::Thread* context, int64_t time, bool clearInterrupted) {
Thread* t = static_cast<Thread*>(context);
if (owner_ == t) {
// Initialized here to make gcc 4.2 a happy compiler
bool interrupted = false;
bool notified = false;
unsigned depth = 0;
{ ACQUIRE(t->mutex);
interrupted = t->r->interrupted();
if (interrupted and clearInterrupted) {
t->r->setInterrupted(false);
}
t->flags |= Waiting;
append(t);
depth = this->depth;
this->depth = 0;
owner_ = 0;
pthread_mutex_unlock(&mutex);
if (not interrupted) {
// pretend anything greater than one million years (in
// milliseconds) is infinity so as to avoid overflow:
if (time and time < INT64_C(31536000000000000)) {
int64_t then = s->now() + time;
timespec ts = { then / 1000, (then % 1000) * 1000 * 1000 };
int rv UNUSED = pthread_cond_timedwait
(&(t->condition), &(t->mutex), &ts);
expect(s, rv == 0 or rv == ETIMEDOUT or rv == EINTR);
} else {
int rv UNUSED = pthread_cond_wait(&(t->condition), &(t->mutex));
expect(s, rv == 0 or rv == EINTR);
}
interrupted = t->r->interrupted();
if (interrupted and clearInterrupted) {
t->r->setInterrupted(false);
}
}
notified = ((t->flags & Notified) != 0);
t->flags = 0;
}
pthread_mutex_lock(&mutex);
if (not notified) {
remove(t);
}
t->next = 0;
owner_ = t;
this->depth = depth;
return interrupted;
} else {
sysAbort(s);
}
}
void doNotify(Thread* t) {
ACQUIRE(t->mutex);
t->flags |= Notified;
int rv UNUSED = pthread_cond_signal(&(t->condition));
expect(s, rv == 0);
}
virtual void notify(System::Thread* context) {
Thread* t = static_cast<Thread*>(context);
if (owner_ == t) {
if (first) {
Thread* t = first;
first = first->next;
if (t == last) {
last = 0;
}
doNotify(t);
}
} else {
sysAbort(s);
}
}
virtual void notifyAll(System::Thread* context) {
Thread* t = static_cast<Thread*>(context);
if (owner_ == t) {
for (Thread* t = first; t; t = t->next) {
doNotify(t);
}
first = last = 0;
} else {
sysAbort(s);
}
}
virtual System::Thread* owner() {
return owner_;
}
virtual void dispose() {
expect(s, owner_ == 0);
pthread_mutex_destroy(&mutex);
s->free(this);
}
System* s;
pthread_mutex_t mutex;
Thread* owner_;
Thread* first;
Thread* last;
unsigned depth;
};
class Local: public System::Local {
public:
Local(System* s): s(s) {
int r UNUSED = pthread_key_create(&key, 0);
expect(s, r == 0);
}
virtual void* get() {
return pthread_getspecific(key);
}
virtual void set(void* p) {
int r UNUSED = pthread_setspecific(key, p);
expect(s, r == 0);
}
virtual void dispose() {
int r UNUSED = pthread_key_delete(key);
expect(s, r == 0);
s->free(this);
}
System* s;
pthread_key_t key;
};
class Region: public System::Region {
public:
Region(System* s, uint8_t* start, size_t length):
s(s),
start_(start),
length_(length)
{ }
virtual const uint8_t* start() {
return start_;
}
virtual size_t length() {
return length_;
}
virtual void dispose() {
if (start_) {
munmap(start_, length_);
}
s->free(this);
}
System* s;
uint8_t* start_;
size_t length_;
};
class Directory: public System::Directory {
public:
Directory(System* s, DIR* directory): s(s), directory(directory) { }
virtual const char* next() {
if (directory) {
dirent* e = readdir(directory);
if (e) {
return e->d_name;
}
}
return 0;
}
virtual void dispose() {
if (directory) {
closedir(directory);
}
s->free(this);
}
System* s;
DIR* directory;
};
class Library: public System::Library {
public:
Library(System* s, void* p, const char* name, unsigned nameLength,
bool isMain):
s(s),
p(p),
mainExecutable(isMain),
name_(name),
nameLength(nameLength),
next_(0)
{ }
virtual void* resolve(const char* function) {
return dlsym(p, function);
}
virtual const char* name() {
return name_;
}
virtual System::Library* next() {
return next_;
}
virtual void setNext(System::Library* lib) {
next_ = lib;
}
virtual void disposeAll() {
if (Verbose) {
fprintf(stderr, "close %p\n", p);
}
if (not mainExecutable) dlclose(p);
if (next_) {
next_->disposeAll();
}
if (name_) {
s->free(name_);
}
s->free(this);
}
System* s;
void* p;
bool mainExecutable;
const char* name_;
unsigned nameLength;
System::Library* next_;
};
MySystem():
threadVisitor(0),
visitTarget(0)
{
expect(this, system == 0);
system = this;
memset(handlers, 0, sizeof(handlers));
registerHandler(&nullHandler, InterruptSignalIndex);
registerHandler(&nullHandler, PipeSignalIndex);
registerHandler(&nullHandler, VisitSignalIndex);
expect(this, make(&visitLock) == 0);
}
int registerHandler(System::SignalHandler* handler, int index) {
if (handler) {
handlers[index] = handler;
struct sigaction sa;
memset(&sa, 0, sizeof(struct sigaction));
sigemptyset(&(sa.sa_mask));
sa.sa_flags = SA_SIGINFO;
sa.sa_sigaction = handleSignal;
return sigaction(signals[index], &sa, oldHandlers + index);
} else if (handlers[index]) {
handlers[index] = 0;
return sigaction(signals[index], oldHandlers + index, 0);
} else {
return 1;
}
}
virtual void* tryAllocate(unsigned sizeInBytes) {
return malloc(sizeInBytes);
}
virtual void free(const void* p) {
if (p) ::free(const_cast<void*>(p));
}
virtual void* tryAllocateExecutable(unsigned sizeInBytes) {
#if (! defined __APPLE__) && (defined __x86_64__)
// map to the lower 32 bits of memory when possible so as to avoid
// expensive relative jumps
const unsigned Extra = MAP_32BIT;
#else
const unsigned Extra = 0;
#endif
void* p = mmap(0, sizeInBytes, PROT_EXEC | PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANON | Extra, -1, 0);
if (p == MAP_FAILED) {
return 0;
} else {
// fprintf(stderr, "executable from %p to %p\n", p,
// static_cast<uint8_t*>(p) + sizeInBytes);
return static_cast<uint8_t*>(p);
}
}
virtual void freeExecutable(const void* p, unsigned sizeInBytes) {
munmap(const_cast<void*>(p), sizeInBytes);
}
virtual bool success(Status s) {
return s == 0;
}
virtual Status attach(Runnable* r) {
Thread* t = new (allocate(this, sizeof(Thread))) Thread(this, r);
t->thread = pthread_self();
r->attach(t);
return 0;
}
virtual Status start(Runnable* r) {
Thread* t = new (allocate(this, sizeof(Thread))) Thread(this, r);
r->attach(t);
int rv UNUSED = pthread_create(&(t->thread), 0, run, r);
expect(this, rv == 0);
return 0;
}
virtual Status make(System::Mutex** m) {
*m = new (allocate(this, sizeof(Mutex))) Mutex(this);
return 0;
}
virtual Status make(System::Monitor** m) {
*m = new (allocate(this, sizeof(Monitor))) Monitor(this);
return 0;
}
virtual Status make(System::Local** l) {
*l = new (allocate(this, sizeof(Local))) Local(this);
return 0;
}
virtual Status handleSegFault(SignalHandler* handler) {
Status s = registerHandler(handler, SegFaultSignalIndex);
if (s == 0 and AltSegFaultSignal != InvalidSignal) {
return registerHandler(handler, AltSegFaultSignalIndex);
}
return s;
}
virtual Status handleDivideByZero(SignalHandler* handler) {
return registerHandler(handler, DivideByZeroSignalIndex);
}
virtual Status visit(System::Thread* st UNUSED, System::Thread* sTarget,
ThreadVisitor* visitor)
{
assert(this, st != sTarget);
Thread* target = static_cast<Thread*>(sTarget);
#ifdef __APPLE__
// On Mac OS, signals sent using pthread_kill are never delivered
// if the target thread is blocked (e.g. acquiring a lock or
// waiting on a condition), so we can't rely on it and must use
// the Mach-specific thread execution API instead.
mach_port_t port = pthread_mach_thread_np(target->thread);
if (thread_suspend(port)) return -1;
THREAD_STATE_TYPE state;
mach_msg_type_number_t stateCount = THREAD_STATE_COUNT;
kern_return_t rv = thread_get_state
(port, THREAD_STATE, reinterpret_cast<thread_state_t>(&state),
&stateCount);
if (rv == 0) {
visitor->visit(reinterpret_cast<void*>(THREAD_STATE_IP(state)),
reinterpret_cast<void*>(THREAD_STATE_STACK(state)),
reinterpret_cast<void*>(THREAD_STATE_LINK(state)));
}
thread_resume(port);
return rv ? -1 : 0;
#else // not __APPLE__
Thread* t = static_cast<Thread*>(st);
ACQUIRE_MONITOR(t, visitLock);
while (threadVisitor) visitLock->wait(t, 0);
threadVisitor = visitor;
visitTarget = target;
int rv = pthread_kill(target->thread, VisitSignal);
int result;
if (rv == 0) {
while (visitTarget) visitLock->wait(t, 0);
result = 0;
} else {
visitTarget = 0;
result = -1;
}
threadVisitor = 0;
system->visitLock->notifyAll(t);
return result;
#endif // not __APPLE__
}
virtual uint64_t call(void* function, uintptr_t* arguments, uint8_t* types,
unsigned count, unsigned size, unsigned returnType)
{
return dynamicCall(function, arguments, types, count, size, returnType);
}
virtual Status map(System::Region** region, const char* name) {
Status status = 1;
int fd = ::open(name, O_RDONLY);
if (fd != -1) {
struct stat s;
int r = fstat(fd, &s);
if (r != -1) {
void* data = mmap(0, s.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
if (data) {
*region = new (allocate(this, sizeof(Region)))
Region(this, static_cast<uint8_t*>(data), s.st_size);
status = 0;
}
}
close(fd);
}
return status;
}
virtual Status open(System::Directory** directory, const char* name) {
Status status = 1;
DIR* d = opendir(name);
if (d) {
*directory = new (allocate(this, sizeof(Directory))) Directory(this, d);
status = 0;
}
return status;
}
virtual FileType stat(const char* name, unsigned* length) {
struct stat s;
int r = ::stat(name, &s);
if (r == 0) {
if (S_ISREG(s.st_mode)) {
*length = s.st_size;
return TypeFile;
} else if (S_ISDIR(s.st_mode)) {
*length = 0;
return TypeDirectory;
} else {
*length = 0;
return TypeUnknown;
}
} else {
*length = 0;
return TypeDoesNotExist;
}
}
virtual const char* libraryPrefix() {
return SO_PREFIX;
}
virtual const char* librarySuffix() {
return SO_SUFFIX;
}
virtual const char* toAbsolutePath(Allocator* allocator, const char* name) {
if (name[0] == '/') {
return copy(allocator, name);
} else {
char buffer[PATH_MAX];
return append(allocator, getcwd(buffer, PATH_MAX), "/", name);
}
}
virtual Status load(System::Library** lib,
const char* name)
{
unsigned nameLength = (name ? strlen(name) : 0);
bool isMain = name == 0;
if (isMain) {
pathOfExecutable(this, &name, &nameLength);
}
void* p = dlopen(name, RTLD_LAZY | RTLD_LOCAL);
if (p) {
if (Verbose) {
fprintf(stderr, "open %s as %p\n", name, p);
}
char* n;
if (name) {
n = static_cast<char*>(allocate(this, nameLength + 1));
memcpy(n, name, nameLength + 1);
if (isMain) {
free(name);
}
} else {
n = 0;
}
*lib = new (allocate(this, sizeof(Library)))
Library(this, p, n, nameLength, isMain);
return 0;
} else {
if (Verbose) {
fprintf(stderr, "dlerror opening %s: %s\n", name, dlerror());
}
return 1;
}
}
virtual char pathSeparator() {
return ':';
}
virtual char fileSeparator() {
return '/';
}
virtual int64_t now() {
timeval tv = { 0, 0 };
gettimeofday(&tv, 0);
return (static_cast<int64_t>(tv.tv_sec) * 1000) +
(static_cast<int64_t>(tv.tv_usec) / 1000);
}
virtual void yield() {
sched_yield();
}
virtual void exit(int code) {
::exit(code);
}
virtual void abort() {
::abort();
}
virtual void dispose() {
visitLock->dispose();
registerHandler(0, InterruptSignalIndex);
registerHandler(0, VisitSignalIndex);
registerHandler(0, PipeSignalIndex);
system = 0;
::free(this);
}
class NullSignalHandler: public SignalHandler {
virtual bool handleSignal(void**, void**, void**, void**) { return false; }
} nullHandler;
SignalHandler* handlers[SignalCount];
struct sigaction oldHandlers[SignalCount];
ThreadVisitor* threadVisitor;
Thread* visitTarget;
System::Monitor* visitLock;
};
void
handleSignal(int signal, siginfo_t*, void* context)
{
ucontext_t* c = static_cast<ucontext_t*>(context);
void* ip = reinterpret_cast<void*>(IP_REGISTER(c));
void* stack = reinterpret_cast<void*>(STACK_REGISTER(c));
void* thread = reinterpret_cast<void*>(THREAD_REGISTER(c));
void* link = reinterpret_cast<void*>(LINK_REGISTER(c));
#ifdef FRAME_REGISTER
void* frame = reinterpret_cast<void*>(FRAME_REGISTER(c));
#else
void* frame = 0;
#endif
unsigned index;
switch (signal) {
case VisitSignal: {
index = VisitSignalIndex;
system->threadVisitor->visit(ip, stack, link);
System::Thread* t = system->visitTarget;
system->visitTarget = 0;
ACQUIRE_MONITOR(t, system->visitLock);
system->visitLock->notifyAll(t);
} break;
case SegFaultSignal:
case AltSegFaultSignal:
case DivideByZeroSignal: {
switch (signal) {
case SegFaultSignal:
index = SegFaultSignalIndex;
break;
case AltSegFaultSignal:
index = AltSegFaultSignalIndex;
break;
case DivideByZeroSignal:
index = DivideByZeroSignalIndex;
break;
default:
abort();
}
bool jump = system->handlers[index]->handleSignal
(&ip, &frame, &stack, &thread);
if (jump) {
// I'd like to use setcontext here (and get rid of the
// sigprocmask call), but it doesn't work on my Linux x86_64
// system, and I can't tell from the documentation if it's even
// supposed to work.
sigset_t set;
sigemptyset(&set);
sigaddset(&set, signal);
pthread_sigmask(SIG_UNBLOCK, &set, 0);
vmJump(ip, frame, stack, thread, 0, 0);
}
} break;
case InterruptSignal: {
index = InterruptSignalIndex;
} break;
case PipeSignal: {
index = PipeSignalIndex;
} break;
default: abort();
}
switch (signal) {
case VisitSignal:
case InterruptSignal:
case PipeSignal:
break;
default:
abort();
}
}
} // namespace
namespace vm {
System*
makeSystem(const char*)
{
return new (malloc(sizeof(MySystem))) MySystem();
}
} // namespace vm