refactor: extract emscripten bridge code

1 files changed, 1434 insertions, 0 deletions

diff --git a/examples/php-on-wasm/emscripten_bridge.php b/examples/php-on-wasm/emscripten_bridge.php
new file mode 100644
index 0000000..b08ad76
--- /dev/null
+++ b/examples/php-on-wasm/emscripten_bridge.php
@@ -0,0 +1,1434 @@
+<?php
+
+declare(strict_types=1);
+
+require_once __DIR__ . '/../../vendor/autoload.php';
+
+use Nsfisis\Waddiwasi\WebAssembly\Execution\Extern;
+use Nsfisis\Waddiwasi\WebAssembly\Execution\Externs;
+use Nsfisis\Waddiwasi\WebAssembly\Execution\FuncInst;
+use Nsfisis\Waddiwasi\WebAssembly\Execution\Linker;
+use Nsfisis\Waddiwasi\WebAssembly\Execution\Refs;
+use Nsfisis\Waddiwasi\WebAssembly\Execution\Runtime;
+use Nsfisis\Waddiwasi\WebAssembly\Execution\Store;
+use Nsfisis\Waddiwasi\WebAssembly\Structure\Types\FuncType;
+use Nsfisis\Waddiwasi\WebAssembly\Structure\Types\ValType;
+
+$imports = [
+    'env' => [
+        'invoke_iii' => makeHostFunc('(i32, i32, i32) -> (i32)', hostFunc__env__invoke_iii(...)),
+        'invoke_iiiii' => makeHostFunc('(i32, i32, i32, i32, i32) -> (i32)', hostFunc__env__invoke_iiiii(...)),
+        'invoke_v' => makeHostFunc('(i32) -> ()', hostFunc__env__invoke_v(...)),
+        'invoke_ii' => makeHostFunc('(i32, i32) -> (i32)', hostFunc__env__invoke_ii(...)),
+        '_abort_js' => makeHostFunc('() -> ()', hostFunc__env___abort_js(...)),
+        'exit' => makeHostFunc('(i32) -> ()', hostFunc__env__exit(...)),
+        'invoke_viii' => makeHostFunc('(i32, i32, i32, i32) -> ()', hostFunc__env__invoke_viii(...)),
+        'invoke_vii' => makeHostFunc('(i32, i32, i32) -> ()', hostFunc__env__invoke_vii(...)),
+        'invoke_vi' => makeHostFunc('(i32, i32) -> ()', hostFunc__env__invoke_vi(...)),
+        'invoke_i' => makeHostFunc('(i32) -> (i32)', hostFunc__env__invoke_i(...)),
+        'invoke_iiiiiii' => makeHostFunc('(i32, i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env__invoke_iiiiiii(...)),
+        'invoke_iiii' => makeHostFunc('(i32, i32, i32, i32) -> (i32)', hostFunc__env__invoke_iiii(...)),
+        '__assert_fail' => makeHostFunc('(i32, i32, i32, i32) -> ()', hostFunc__env____assert_fail(...)),
+        'invoke_viiii' => makeHostFunc('(i32, i32, i32, i32, i32) -> ()', hostFunc__env__invoke_viiii(...)),
+        'invoke_viiiii' => makeHostFunc('(i32, i32, i32, i32, i32, i32) -> ()', hostFunc__env__invoke_viiiii(...)),
+        'invoke_iiiiii' => makeHostFunc('(i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env__invoke_iiiiii(...)),
+        'invoke_iiiiiiiiii' => makeHostFunc('(i32, i32, i32, i32, i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env__invoke_iiiiiiiiii(...)),
+        'strftime' => makeHostFunc('(i32, i32, i32, i32) -> (i32)', hostFunc__env__strftime(...)),
+        'getaddrinfo' => makeHostFunc('(i32, i32, i32, i32) -> (i32)', hostFunc__env__getaddrinfo(...)),
+        'posix_spawnp' => makeHostFunc('(i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env__posix_spawnp(...)),
+        'getdtablesize' => makeHostFunc('() -> (i32)', hostFunc__env__getdtablesize(...)),
+        'getprotobyname' => makeHostFunc('(i32) -> (i32)', hostFunc__env__getprotobyname(...)),
+        'getprotobynumber' => makeHostFunc('(i32) -> (i32)', hostFunc__env__getprotobynumber(...)),
+        'strptime' => makeHostFunc('(i32, i32, i32) -> (i32)', hostFunc__env__strptime(...)),
+        'getnameinfo' => makeHostFunc('(i32, i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env__getnameinfo(...)),
+        'invoke_viidii' => makeHostFunc('(i32, i32, i32, f64, i32, i32) -> ()', hostFunc__env__invoke_viidii(...)),
+        'getcontext' => makeHostFunc('(i32) -> (i32)', hostFunc__env__getcontext(...)),
+        'makecontext' => makeHostFunc('(i32, i32, i32, i32) -> ()', hostFunc__env__makecontext(...)),
+        'swapcontext' => makeHostFunc('(i32, i32) -> (i32)', hostFunc__env__swapcontext(...)),
+        '__syscall_fcntl64' => makeHostFunc('(i32, i32, i32) -> (i32)', hostFunc__env____syscall_fcntl64(...)),
+        '__syscall_ioctl' => makeHostFunc('(i32, i32, i32) -> (i32)', hostFunc__env____syscall_ioctl(...)),
+        '__syscall_faccessat' => makeHostFunc('(i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_faccessat(...)),
+        '__syscall_chdir' => makeHostFunc('(i32) -> (i32)', hostFunc__env____syscall_chdir(...)),
+        '__syscall_chmod' => makeHostFunc('(i32, i32) -> (i32)', hostFunc__env____syscall_chmod(...)),
+        '__syscall_fchownat' => makeHostFunc('(i32, i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_fchownat(...)),
+        '__syscall_dup' => makeHostFunc('(i32) -> (i32)', hostFunc__env____syscall_dup(...)),
+        '_emscripten_memcpy_js' => makeHostFunc('(i32, i32, i32) -> ()', hostFunc__env___emscripten_memcpy_js(...)),
+        'emscripten_date_now' => makeHostFunc('() -> (f64)', hostFunc__env__emscripten_date_now(...)),
+        'emscripten_get_now' => makeHostFunc('() -> (f64)', hostFunc__env__emscripten_get_now(...)),
+        '__syscall_fdatasync' => makeHostFunc('(i32) -> (i32)', hostFunc__env____syscall_fdatasync(...)),
+        '__syscall_openat' => makeHostFunc('(i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_openat(...)),
+        '__syscall_fstat64' => makeHostFunc('(i32, i32) -> (i32)', hostFunc__env____syscall_fstat64(...)),
+        '__syscall_stat64' => makeHostFunc('(i32, i32) -> (i32)', hostFunc__env____syscall_stat64(...)),
+        '__syscall_newfstatat' => makeHostFunc('(i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_newfstatat(...)),
+        '__syscall_lstat64' => makeHostFunc('(i32, i32) -> (i32)', hostFunc__env____syscall_lstat64(...)),
+        '__syscall_getcwd' => makeHostFunc('(i32, i32) -> (i32)', hostFunc__env____syscall_getcwd(...)),
+        'emscripten_err' => makeHostFunc('(i32) -> ()', hostFunc__env__emscripten_err(...)),
+        '__syscall_mkdirat' => makeHostFunc('(i32, i32, i32) -> (i32)', hostFunc__env____syscall_mkdirat(...)),
+        '__syscall_pipe' => makeHostFunc('(i32) -> (i32)', hostFunc__env____syscall_pipe(...)),
+        '__syscall_poll' => makeHostFunc('(i32, i32, i32) -> (i32)', hostFunc__env____syscall_poll(...)),
+        '_emscripten_runtime_keepalive_clear' => makeHostFunc('() -> ()', hostFunc__env___emscripten_runtime_keepalive_clear(...)),
+        '__call_sighandler' => makeHostFunc('(i32, i32) -> ()', hostFunc__env____call_sighandler(...)),
+        '__syscall_getdents64' => makeHostFunc('(i32, i32, i32) -> (i32)', hostFunc__env____syscall_getdents64(...)),
+        '__syscall_readlinkat' => makeHostFunc('(i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_readlinkat(...)),
+        '__syscall_renameat' => makeHostFunc('(i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_renameat(...)),
+        '__syscall_rmdir' => makeHostFunc('(i32) -> (i32)', hostFunc__env____syscall_rmdir(...)),
+        '__syscall__newselect' => makeHostFunc('(i32, i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall__newselect(...)),
+        '_setitimer_js' => makeHostFunc('(i32, f64) -> (i32)', hostFunc__env___setitimer_js(...)),
+        '__syscall_statfs64' => makeHostFunc('(i32, i32, i32) -> (i32)', hostFunc__env____syscall_statfs64(...)),
+        '__syscall_symlinkat' => makeHostFunc('(i32, i32, i32) -> (i32)', hostFunc__env____syscall_symlinkat(...)),
+        'emscripten_get_heap_max' => makeHostFunc('() -> (i32)', hostFunc__env__emscripten_get_heap_max(...)),
+        '_tzset_js' => makeHostFunc('(i32, i32, i32) -> ()', hostFunc__env___tzset_js(...)),
+        '__syscall_unlinkat' => makeHostFunc('(i32, i32, i32) -> (i32)', hostFunc__env____syscall_unlinkat(...)),
+        '__syscall_utimensat' => makeHostFunc('(i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_utimensat(...)),
+        'emscripten_resize_heap' => makeHostFunc('(i32) -> (i32)', hostFunc__env__emscripten_resize_heap(...)),
+        '_emscripten_throw_longjmp' => makeHostFunc('() -> ()', hostFunc__env___emscripten_throw_longjmp(...)),
+        '__syscall_accept4' => makeHostFunc('(i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_accept4(...)),
+        '__syscall_bind' => makeHostFunc('(i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_bind(...)),
+        '__syscall_connect' => makeHostFunc('(i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_connect(...)),
+        '_emscripten_lookup_name' => makeHostFunc('(i32) -> (i32)', hostFunc__env___emscripten_lookup_name(...)),
+        '__syscall_getpeername' => makeHostFunc('(i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_getpeername(...)),
+        '__syscall_getsockname' => makeHostFunc('(i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_getsockname(...)),
+        '__syscall_getsockopt' => makeHostFunc('(i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_getsockopt(...)),
+        '__syscall_listen' => makeHostFunc('(i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_listen(...)),
+        '__syscall_recvfrom' => makeHostFunc('(i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_recvfrom(...)),
+        '__syscall_sendto' => makeHostFunc('(i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_sendto(...)),
+        '__syscall_socket' => makeHostFunc('(i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env____syscall_socket(...)),
+        '__syscall_ftruncate64' => makeHostFunc('(i32, i32, i32) -> (i32)', hostFunc__env____syscall_ftruncate64(...)),
+        '_mktime_js' => makeHostFunc('(i32) -> (i32)', hostFunc__env___mktime_js(...)),
+        '_localtime_js' => makeHostFunc('(i32, i32, i32) -> ()', hostFunc__env___localtime_js(...)),
+        '_gmtime_js' => makeHostFunc('(i32, i32, i32) -> ()', hostFunc__env___gmtime_js(...)),
+        '_munmap_js' => makeHostFunc('(i32, i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env___munmap_js(...)),
+        '_mmap_js' => makeHostFunc('(i32, i32, i32, i32, i32, i32, i32, i32) -> (i32)', hostFunc__env___mmap_js(...)),
+    ],
+    'wasi_snapshot_preview1' => [
+        'environ_sizes_get' => makeHostFunc('(i32, i32) -> (i32)', hostFunc__wasi_snapshot_preview1__environ_sizes_get(...)),
+        'environ_get' => makeHostFunc('(i32, i32) -> (i32)', hostFunc__wasi_snapshot_preview1__environ_get(...)),
+        'fd_close' => makeHostFunc('(i32) -> (i32)', hostFunc__wasi_snapshot_preview1__fd_close(...)),
+        'fd_read' => makeHostFunc('(i32, i32, i32, i32) -> (i32)', hostFunc__wasi_snapshot_preview1__fd_read(...)),
+        'fd_write' => makeHostFunc('(i32, i32, i32, i32) -> (i32)', hostFunc__wasi_snapshot_preview1__fd_write(...)),
+        'proc_exit' => makeHostFunc('(i32) -> ()', hostFunc__wasi_snapshot_preview1__proc_exit(...)),
+        'fd_sync' => makeHostFunc('(i32) -> (i32)', hostFunc__wasi_snapshot_preview1__fd_sync(...)),
+        'fd_fdstat_get' => makeHostFunc('(i32, i32) -> (i32)', hostFunc__wasi_snapshot_preview1__fd_fdstat_get(...)),
+        'clock_time_get' => makeHostFunc('(i32, i32, i32, i32) -> (i32)', hostFunc__wasi_snapshot_preview1__clock_time_get(...)),
+        'fd_seek' => makeHostFunc('(i32, i32, i32, i32, i32) -> (i32)', hostFunc__wasi_snapshot_preview1__fd_seek(...)),
+    ],
+];
+
+$store = Store::empty();
+$linker = new Linker($store);
+
+foreach ($imports as $moduleName => $moduleImports) {
+    foreach ($moduleImports as $importName => $import) {
+        $linker->register($moduleName, $importName, $import);
+    }
+}
+
+return $linker;
+
+function allocateStringOnWasmMemory(Runtime $runtime, string $str): int
+{
+    // Plus 1 for the null terminator in C.
+    $size = \strlen($str) + 1;
+    $outPtr = _emscripten_stack_alloc($runtime, $size);
+    copyStringToWasmMemory($runtime, $outPtr, $str);
+    return $outPtr;
+}
+
+function _emscripten_stack_alloc(Runtime $runtime, int $size): int
+{
+    $results = $runtime->invoke("_emscripten_stack_alloc", [$size]);
+    \assert(\count($results) === 1);
+    $result = $results[0];
+    \assert(\is_int($result));
+    return $result;
+}
+
+function emscripten_stack_get_current(Runtime $runtime): int
+{
+    $results = $runtime->invoke("emscripten_stack_get_current", []);
+    \assert(\count($results) === 1);
+    $result = $results[0];
+    \assert(\is_int($result));
+    return $result;
+}
+
+function copyStringToWasmMemory(Runtime $runtime, int $dst, string $src): void
+{
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+    for ($i = 0; $i < \strlen($src); $i++) {
+        $ok = $mem->storeByte($dst + $i, \ord($src[$i]));
+        \assert($ok);
+    }
+    // Terminate the string with a null byte for interoperation with C.
+    $ok = $mem->storeByte($dst + \strlen($src), 0);
+    \assert($ok);
+}
+
+function makeHostFunc(string $typeDef, callable $fn): Externs\Func
+{
+    $stringToType = fn (string $s) => match ($s) {
+        'i32' => ValType::I32,
+        'i64' => ValType::I64,
+        'f32' => ValType::F32,
+        'f64' => ValType::F64,
+        default => throw new \RuntimeException('Invalid type: ' . $s),
+    };
+    $ok = preg_match('/^\(([^)]*)\) -> \(([^)]*)\)$/', $typeDef, $matches);
+    \assert($ok === 1);
+    $paramsDef = $matches[1];
+    $resultsDef = $matches[2];
+    $params = array_map($stringToType, $paramsDef === '' ? [] : explode(', ', $paramsDef));
+    $results = array_map($stringToType, $resultsDef === '' ? [] : explode(', ', $resultsDef));
+    $type = new FuncType($params, $results);
+    return Extern::Func(FuncInst::Host($type, $fn));
+}
+
+function getWasmTableEntry(Runtime $runtime, int $funcPtr): int
+{
+    static $wasmTable = null;
+
+    if ($wasmTable === null) {
+        $wasmTable = $runtime->getExportedTable('__indirect_function_table');
+        \assert($wasmTable !== null);
+    }
+
+    $func = $wasmTable->elem[$funcPtr] ?? null;
+    \assert($func instanceof Refs\RefFunc, "Expected RefFunc, but got " . \get_class($func));
+    return $func->addr;
+}
+
+function syscallGetStr(Runtime $runtime, int $ptr): string
+{
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+    $str = '';
+    for ($i = $ptr; $mem->loadByte($i) !== 0; $i++) {
+        $c = $mem->loadByte($i);
+        \assert($c !== null);
+        $str .= \chr($c);
+    }
+    return $str;
+}
+
+function stringToUTF8(Runtime $runtime, string $s, int $ptr, $len): void
+{
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+    for ($i = 0; $i < $len; $i++) {
+        if ($i < \strlen($s)) {
+            $mem->storeByte($ptr + $i, \ord($s[$i]));
+        } else {
+            $mem->storeByte($ptr + $i, 0);
+        }
+    }
+}
+
+function heap8Write(Runtime $runtime, int $ptr, int $value): void
+{
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+    $mem->storeI32_s8($ptr, $value);
+}
+
+function heap16Write(Runtime $runtime, int $ptr, int $value): void
+{
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+    $mem->storeI32_s16($ptr, $value);
+}
+
+function heap32Write(Runtime $runtime, int $ptr, int $value): void
+{
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+    $mem->storeI32_s32($ptr, $value);
+}
+
+function heapU32Write(Runtime $runtime, int $ptr, int $value): void
+{
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+    $mem->storeI32_s32($ptr, $value);
+}
+
+function heap64Write(Runtime $runtime, int $ptr, int $value): void
+{
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+    $mem->storeI64_s64($ptr, $value);
+}
+
+function syscallDoStat(Runtime $runtime, callable $func, string $path, int $buf): void
+{
+    $stat = $func($path);
+
+    heap32Write($runtime, $buf, $stat->dev);
+    heap32Write($runtime, $buf + 4, $stat->mode);
+    heapU32Write($runtime, $buf + 8, $stat->nlink);
+    heap32Write($runtime, $buf + 12, $stat->uid);
+    heap32Write($runtime, $buf + 16, $stat->gid);
+    heap32Write($runtime, $buf + 20, $stat->rdev);
+    heap64Write($runtime, $buf + 24, $stat->size);
+    heap32Write($runtime, $buf + 32, 4096);
+    heap32Write($runtime, $buf + 36, $stat->blocks);
+    $atime = $stat->atime;
+    heap64Write($runtime, $buf + 40, $atime);
+    heapU32Write($runtime, $buf + 48, ($atime % 1000) * 1000);
+    $mtime = $stat->mtime;
+    heap64Write($runtime, $buf + 56, $mtime);
+    heapU32Write($runtime, $buf + 64, ($mtime % 1000) * 1000);
+    $ctime = $stat->ctime;
+    heap64Write($runtime, $buf + 72, $ctime);
+    heapU32Write($runtime, $buf + 80, ($ctime % 1000) * 1000);
+    heap64Write($runtime, $buf + 88, $stat->ino);
+}
+
+function syscallCalculateAt(Runtime $runtime, int $dirfd, string $path): string
+{
+    if ($path[0] === '/') {
+        return $path;
+    }
+    if ($dirfd === -100) {
+        $dir = getcwd();
+        \assert($dir !== false);
+    } else {
+        throw new \RuntimeException("syscallCalculateAt: not implemented ($dirfd)");
+    }
+    if ($path === '.') {
+        return $dir;
+    } else {
+        return $dir . '/' . $path;
+    }
+}
+
+function fsStat(string $path, bool $dontFollow): object
+{
+    if ($path === 'php://stdin') {
+        return (object)[
+            'dev' => 0,
+            'mode' => 0,
+            'nlink' => 0,
+            'uid' => 0,
+            'gid' => 0,
+            'rdev' => 0,
+            'size' => 0,
+            'blocks' => 0,
+            'ino' => 0,
+            'atime' => 0,
+            'mtime' => 0,
+            'ctime' => 0,
+        ];
+    } elseif ($path === 'php://stdout') {
+        return (object)[
+            'dev' => 0,
+            'mode' => 0,
+            'nlink' => 0,
+            'uid' => 0,
+            'gid' => 0,
+            'rdev' => 0,
+            'size' => 0,
+            'blocks' => 0,
+            'ino' => 1,
+            'atime' => 0,
+            'mtime' => 0,
+            'ctime' => 0,
+        ];
+    } elseif ($path === 'php://stderr') {
+        return (object)[
+            'dev' => 0,
+            'mode' => 0,
+            'nlink' => 0,
+            'uid' => 0,
+            'gid' => 0,
+            'rdev' => 0,
+            'size' => 0,
+            'blocks' => 0,
+            'ino' => 2,
+            'atime' => 0,
+            'mtime' => 0,
+            'ctime' => 0,
+        ];
+    }
+
+    $phpStat = $dontFollow ? lstat($path) : stat($path);
+    \assert($phpStat !== false);
+    return (object)[
+        'dev' => $phpStat['dev'],
+        'mode' => $phpStat['mode'],
+        'nlink' => $phpStat['nlink'],
+        'uid' => $phpStat['uid'],
+        'gid' => $phpStat['gid'],
+        'rdev' => $phpStat['rdev'],
+        'size' => $phpStat['size'],
+        'blocks' => $phpStat['blocks'],
+        'ino' => $phpStat['ino'],
+        'atime' => $phpStat['atime'] * 1000,
+        'mtime' => $phpStat['mtime'] * 1000,
+        'ctime' => $phpStat['ctime'] * 1000,
+    ];
+}
+
+function fsLstat(string $path): object
+{
+    return fsStat($path, true);
+}
+
+final class VFile
+{
+    public ?array $getdents = null;
+
+    /**
+     * @param resource $fp
+     */
+    public function __construct(
+        public readonly int $fd,
+        public readonly mixed $fp,
+        public readonly int $flags,
+        public readonly string $path,
+    ) {
+    }
+
+    public function seek(int $offset, int $whence): int
+    {
+        if ($whence === 0) {
+            fseek($this->fp, $offset, SEEK_SET);
+        } elseif ($whence === 1) {
+            fseek($this->fp, $offset, SEEK_CUR);
+        } elseif ($whence === 2) {
+            fseek($this->fp, $offset, SEEK_END);
+        } else {
+            throw new \RuntimeException("VFile::seek: invalid whence");
+        }
+        $pos = ftell($this->fp);
+        return $pos === false ? 0 : $pos;
+    }
+
+    public function read(Runtime $runtime, int $len): string
+    {
+        return fread($this->fp, $len);
+    }
+
+    public function close(): void
+    {
+        fclose($this->fp);
+    }
+}
+
+function fsOpen(string $path, int $flags, int $mode): ?int
+{
+    global $fdTable;
+    if (!isset($fdTable)) {
+        $fdTable = [];
+    }
+    $fp = @fopen($path, 'r');
+    if ($fp === false) {
+        return null;
+    }
+    $nextFd = \count($fdTable) + 10;
+    $fdTable[$nextFd] = new VFile(
+        $nextFd,
+        $fp,
+        $flags,
+        $path,
+    );
+    return $nextFd;
+}
+
+function fsDup(int $fd): ?int
+{
+    global $fdTable;
+    if (!isset($fdTable)) {
+        return null;
+    }
+    $nextFd = \count($fdTable) + 10;
+    if ($fd === 0) {
+        $fp = fopen('php://stdin', 'r');
+        $fdTable[$nextFd] = new VFile(
+            $nextFd,
+            $fp,
+            0,
+            'php://stdin',
+        );
+    } elseif ($fd === 1) {
+        $fp = fopen('php://stdout', 'w');
+        $fdTable[$nextFd] = new VFile(
+            $nextFd,
+            $fp,
+            0,
+            'php://stdout',
+        );
+    } elseif ($fd === 2) {
+        $fp = fopen('php://stderr', 'w');
+        $fdTable[$nextFd] = new VFile(
+            $nextFd,
+            $fp,
+            0,
+            'php://stderr',
+        );
+    } else {
+        $file = $fdTable[$fd];
+        $fp = $file->fp;
+        $fdTable[$nextFd] = new VFile(
+            $nextFd,
+            $fp,
+            $file->flags,
+            $file->path,
+        );
+    }
+    return $nextFd;
+}
+
+function fsGetVFileFromFd(int $fd): ?VFile
+{
+    global $fdTable;
+    return $fdTable[$fd] ?? null;
+}
+
+function fsGetPathFromFd(int $fd): ?string
+{
+    return fsGetVFileFromFd($fd)?->path;
+}
+
+function fsGetFpFromFd(int $fd): mixed
+{
+    return fsGetVFileFromFd($fd)?->fp;
+}
+
+function fsGetFlagsFromFd(int $fd): ?int
+{
+    return fsGetVFileFromFd($fd)?->flags;
+}
+
+function fsReaddir(string $p): array
+{
+    $dir = opendir($p);
+    $entries = [];
+    while (($entry = readdir($dir)) !== false) {
+        $entries[] = $entry;
+    }
+    closedir($dir);
+    return $entries;
+}
+
+function fsLookupParentPath(string $p): string
+{
+    return realpath($p . '/..');
+}
+
+function fsLookupChild(string $p, string $c): string
+{
+    return realpath($p . '/' . $c);
+}
+
+function alignMemory(int $size, int $alignment): int
+{
+    return (int)ceil($size / $alignment) * $alignment;
+}
+
+function _emscripten_builtin_memalign(Runtime $runtime, int $alignment, int $size): int
+{
+    $results = $runtime->invoke("emscripten_builtin_memalign", [$alignment, $size]);
+    \assert(\count($results) === 1);
+    $result = $results[0];
+    \assert(\is_int($result));
+    return $result;
+}
+
+function zeroMemory(Runtime $runtime, int $ptr, int $len): int
+{
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+    for ($i = 0; $i < $len; $i++) {
+        $mem->storeByte($ptr + $i, 0);
+    }
+    return $ptr;
+}
+
+function mmapAlloc(Runtime $runtime, int $len): int
+{
+    $len = alignMemory($len, 65536);
+    $ptr = _emscripten_builtin_memalign($runtime, 65536, $len);
+    if ($ptr === 0) {
+        return 0;
+    }
+    return zeroMemory($runtime, $ptr, $len);
+}
+
+function fsMmap(Runtime $runtime, int $fd, int $len, int $offset, int $prot, int $flags): array
+{
+    global $fdTable;
+    if (!isset($fdTable[$fd])) {
+        throw new \RuntimeException("fsMmap: invalid fd");
+    }
+    $file = $fdTable[$fd];
+
+    $buf = stream_get_contents($file->fp);
+
+    $ptr = mmapAlloc($runtime, $len);
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+    for ($i = 0; $i < $len; $i++) {
+        $mem->storeByte($ptr + $i, \ord($buf[$i]));
+    }
+
+    return [$ptr, 1];
+}
+
+// Type: (i32, i32, i32) -> (i32)
+function hostFunc__env__invoke_iii(Runtime $runtime, int $index, int $a1, int $a2): int
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->stack->pushValue($a2);
+    $runtime->invokeByFuncAddr($func);
+    return $runtime->stack->popInt();
+}
+
+// Type: (i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env__invoke_iiiii(Runtime $runtime, int $index, int $a1, int $a2, int $a3, int $a4): int
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->stack->pushValue($a2);
+    $runtime->stack->pushValue($a3);
+    $runtime->stack->pushValue($a4);
+    $runtime->invokeByFuncAddr($func);
+    return $runtime->stack->popInt();
+}
+
+// Type: (i32) -> ()
+function hostFunc__env__invoke_v(Runtime $runtime, int $index): void
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->invokeByFuncAddr($func);
+}
+
+// Type: (i32, i32, i32, i32) -> (i32)
+function hostFunc__env__invoke_iiii(Runtime $runtime, int $index, int $a1, int $a2, int $a3): int
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->stack->pushValue($a2);
+    $runtime->stack->pushValue($a3);
+    $runtime->invokeByFuncAddr($func);
+    return $runtime->stack->popInt();
+}
+
+// Type: (i32, i32) -> (i32)
+function hostFunc__env__invoke_ii(Runtime $runtime, int $index, int $a1): int
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->invokeByFuncAddr($func);
+    return $runtime->stack->popInt();
+}
+
+// Type: () -> ()
+function hostFunc__env___abort_js(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::_abort_js: not implemented');
+}
+
+// Type: (i32) -> ()
+function hostFunc__env__exit(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::exit: not implemented');
+}
+
+// Type: (i32, i32, i32, i32) -> ()
+function hostFunc__env__invoke_viii(Runtime $runtime, int $index, int $a1, int $a2, int $a3): void
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->stack->pushValue($a2);
+    $runtime->stack->pushValue($a3);
+    $runtime->invokeByFuncAddr($func);
+}
+
+// Type: (i32, i32, i32) -> ()
+function hostFunc__env__invoke_vii(Runtime $runtime, int $index, int $a1, int $a2): void
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->stack->pushValue($a2);
+    $runtime->invokeByFuncAddr($func);
+}
+
+// Type: (i32, i32) -> ()
+function hostFunc__env__invoke_vi(Runtime $runtime, int $index, int $a1): void
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->invokeByFuncAddr($func);
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__env__invoke_i(Runtime $runtime, int $index): int
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->invokeByFuncAddr($func);
+    return $runtime->stack->popInt();
+}
+
+// Type: (i32, i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env__invoke_iiiiiii(Runtime $runtime, int $index, int $a1, int $a2, int $a3, int $a4, int $a5, int $a6): int
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->stack->pushValue($a2);
+    $runtime->stack->pushValue($a3);
+    $runtime->stack->pushValue($a4);
+    $runtime->stack->pushValue($a5);
+    $runtime->stack->pushValue($a6);
+    $runtime->invokeByFuncAddr($func);
+    return $runtime->stack->popInt();
+}
+
+// Type: (i32, i32, i32, i32) -> ()
+function hostFunc__env____assert_fail(Runtime $runtime, int $index, int $a1, int $a2, int $a3): void
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->stack->pushValue($a2);
+    $runtime->stack->pushValue($a3);
+    $runtime->invokeByFuncAddr($func);
+}
+
+// Type: (i32, i32, i32, i32, i32) -> ()
+function hostFunc__env__invoke_viiii(Runtime $runtime, int $index, int $a1, int $a2, int $a3, int $a4): void
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->stack->pushValue($a2);
+    $runtime->stack->pushValue($a3);
+    $runtime->stack->pushValue($a4);
+    $runtime->invokeByFuncAddr($func);
+}
+
+// Type: (i32, i32, i32, i32, i32, i32) -> ()
+function hostFunc__env__invoke_viiiii(Runtime $runtime, int $index, int $a1, int $a2, int $a3, int $a4, int $a5): void
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->stack->pushValue($a2);
+    $runtime->stack->pushValue($a3);
+    $runtime->stack->pushValue($a4);
+    $runtime->stack->pushValue($a5);
+    $runtime->invokeByFuncAddr($func);
+}
+
+// Type: (i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env__invoke_iiiiii(Runtime $runtime, int $index, int $a1, int $a2, int $a3, int $a4, int $a5): int
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->stack->pushValue($a2);
+    $runtime->stack->pushValue($a3);
+    $runtime->stack->pushValue($a4);
+    $runtime->stack->pushValue($a5);
+    $runtime->invokeByFuncAddr($func);
+    return $runtime->stack->popInt();
+}
+
+// Type: (i32, i32, i32, i32, i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env__invoke_iiiiiiiiii(Runtime $runtime, int $index, int $a1, int $a2, int $a3, int $a4, int $a5, int $a6, int $a7, int $a8, int $a9): int
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->stack->pushValue($a2);
+    $runtime->stack->pushValue($a3);
+    $runtime->stack->pushValue($a4);
+    $runtime->stack->pushValue($a5);
+    $runtime->stack->pushValue($a6);
+    $runtime->stack->pushValue($a7);
+    $runtime->stack->pushValue($a8);
+    $runtime->stack->pushValue($a9);
+    $runtime->invokeByFuncAddr($func);
+    return $runtime->stack->popInt();
+}
+
+// Type: (i32, i32, i32, i32) -> (i32)
+function hostFunc__env__strftime(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::strftime: not implemented');
+}
+
+// Type: (i32, i32, i32, i32) -> (i32)
+function hostFunc__env__getaddrinfo(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::getaddrinfo: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env__posix_spawnp(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::posix_spawnp: not implemented');
+}
+
+// Type: () -> (i32)
+function hostFunc__env__getdtablesize(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::getdtablesize: not implemented');
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__env__getprotobyname(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::getprotobyname: not implemented');
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__env__getprotobynumber(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::getprotobynumber: not implemented');
+}
+
+// Type: (i32, i32, i32) -> (i32)
+function hostFunc__env__strptime(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::strptime: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env__getnameinfo(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::getnameinfo: not implemented');
+}
+
+// Type: (i32, i32, i32, f64, i32, i32) -> ()
+function hostFunc__env__invoke_viidii(Runtime $runtime, int $index, int $a1, int $a2, float $a3, int $a4, int $a5): void
+{
+    $sp = emscripten_stack_get_current($runtime);
+    $func = getWasmTableEntry($runtime, $index);
+    $runtime->stack->pushValue($a1);
+    $runtime->stack->pushValue($a2);
+    $runtime->stack->pushValue($a3);
+    $runtime->stack->pushValue($a4);
+    $runtime->stack->pushValue($a5);
+    $runtime->invokeByFuncAddr($func);
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__env__getcontext(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::getcontext: not implemented');
+}
+
+// Type: (i32, i32, i32, i32) -> ()
+function hostFunc__env__makecontext(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::makecontext: not implemented');
+}
+
+// Type: (i32, i32) -> (i32)
+function hostFunc__env__swapcontext(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::swapcontext: not implemented');
+}
+
+// Type: (i32, i32) -> (i32)
+function hostFunc__wasi_snapshot_preview1__environ_sizes_get(Runtime $runtime): void
+{
+    throw new \RuntimeException('wasi_snapshot_preview1::environ_sizes_get: not implemented');
+}
+
+// Type: (i32, i32) -> (i32)
+function hostFunc__wasi_snapshot_preview1__environ_get(Runtime $runtime): void
+{
+    throw new \RuntimeException('wasi_snapshot_preview1::environ_get: not implemented');
+}
+
+// Type: (i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_fcntl64(Runtime $runtime, int $fd, int $cmd, int $varargs): int
+{
+    switch ($cmd) {
+        case 0:
+            throw new \RuntimeException("env::__syscall_fcntl64: command $cmd not implemented");
+        case 1:
+        case 2:
+            return 0;
+        case 3:
+            return fsGetFlagsFromFd($fd);
+        case 4:
+            throw new \RuntimeException("env::__syscall_fcntl64: command $cmd not implemented");
+        case 5:
+            throw new \RuntimeException("env::__syscall_fcntl64: command $cmd not implemented");
+        case 6:
+        case 7:
+            return 0;
+        case 16:
+        case 8:
+            return -28;
+        case 9:
+            // setErrno(28);
+            return -1;
+        default:
+            return -28;
+    }
+}
+
+// Type: (i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_ioctl(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_ioctl: not implemented');
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__wasi_snapshot_preview1__fd_close(Runtime $runtime, int $fd): int
+{
+    if ($fd === -1) {
+        // should report an error?
+        return 0;
+    }
+    $file = fsGetVFileFromFd($fd);
+    \assert($file !== null);
+    $file->close();
+    return 0;
+}
+
+// Type: (i32, i32, i32, i32) -> (i32)
+function hostFunc__wasi_snapshot_preview1__fd_read(Runtime $runtime, int $fd, int $iov, int $iovcnt, int $pnum): int
+{
+    $file = fsGetVFileFromFd($fd);
+    \assert($file !== null);
+
+    // struct iov {
+    //   ptr: u32, pointer to the data
+    //   len: u32
+    // }
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+
+    $nRead = 0;
+    for ($i = 0; $i < $iovcnt; $i++) {
+        $ptr = $mem->loadI32_s32($iov + $i * 8);
+        \assert($ptr !== null);
+        $len = $mem->loadI32_s32($iov + $i * 8 + 4);
+        \assert($len !== null);
+        $buf = $file->read($runtime, $len);
+        if ($buf === false) {
+            $nRead = -1;
+            break;
+        }
+        $curr = \strlen($buf);
+        if ($curr <= 0) {
+            $nRead = -1;
+            break;
+        }
+        // echo "fd_read(fd=$fd, iov=$iov, iovcnt=$iovcnt, pnum=$pnum) = { p=$ptr, l=$len }\n";
+        for ($k = 0; $k < $curr; $k++) {
+            $mem->storeByte($ptr + $k, \ord($buf[$k]));
+            // echo "  [$k] = ord($buf[$k])\n";
+        }
+        $nRead += $curr;
+        if ($curr < $len) {
+            break;
+        }
+    }
+
+    $mem->storeI32_s32($pnum, $nRead);
+
+    return 0;
+}
+
+// Type: (i32, i32, i32, i32) -> (i32)
+function hostFunc__wasi_snapshot_preview1__fd_write(Runtime $runtime, int $fd, int $iov, int $iovcnt, int $pnum): int
+{
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+
+    // struct iov {
+    //   ptr: u32, pointer to the data
+    //   len: u32
+    // }
+    $nWritten = 0;
+    for ($i = 0; $i < $iovcnt; $i++) {
+        $ptr = $mem->loadI32_s32($iov + $i * 8);
+        \assert($ptr !== null);
+        $len = $mem->loadI32_s32($iov + $i * 8 + 4);
+        // echo "fd_write($iovcnt, $iov) [$i] = { p=$ptr, l=$len };\n";
+        \assert($len !== null);
+        $buf = '';
+        for ($j = 0; $j < $len; $j++) {
+            $c = $mem->loadByte($ptr + $j);
+            \assert($c !== null);
+            $buf .= \chr($c);
+        }
+        if ($fd === 1) {
+            fputs(STDOUT, $buf);
+        } else {
+            fputs(STDERR, $buf);
+        }
+        $nWritten += $len;
+    }
+    $mem->storeI32_s32($pnum, $nWritten);
+
+    return 0;
+}
+
+// Type: (i32) -> ()
+function hostFunc__wasi_snapshot_preview1__proc_exit(Runtime $runtime): void
+{
+    throw new \RuntimeException('wasi_snapshot_preview1::proc_exit: not implemented');
+}
+
+// Type: (i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_faccessat(Runtime $runtime, int $dirfd, int $path, int $amode, int $flags): int
+{
+    $path = syscallGetStr($runtime, $path);
+    $path = syscallCalculateAt($runtime, $dirfd, $path);
+
+    // Always allow accesses.
+    return 0;
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__env____syscall_chdir(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_chdir: not implemented');
+}
+
+// Type: (i32, i32) -> (i32)
+function hostFunc__env____syscall_chmod(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_chmod: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_fchownat(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_fchownat: not implemented');
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__env____syscall_dup(Runtime $runtime, int $oldFd): int
+{
+    return fsDup($oldFd);
+}
+
+// Type: (i32, i32, i32) -> ()
+function hostFunc__env___emscripten_memcpy_js(Runtime $runtime, int $dest, int $src, int $num): void
+{
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+    for ($i = 0; $i < $num; $i++) {
+        $byte = $mem->loadByte($src + $i);
+        \assert($byte !== null);
+        $mem->storeByte($dest + $i, $byte);
+    }
+}
+
+// Type: () -> (f64)
+function hostFunc__env__emscripten_date_now(Runtime $runtime): float
+{
+    return round(microtime(true) * 1000);
+}
+
+// Type: () -> (f64)
+function hostFunc__env__emscripten_get_now(Runtime $runtime): float
+{
+    return round(microtime(true) * 1000);
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__env____syscall_fdatasync(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_fdatasync: not implemented');
+}
+
+// Type: (i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_openat(Runtime $runtime, int $dirfd, int $path, int $flags, int $varargs): int
+{
+    $path = syscallGetStr($runtime, $path);
+    $path = syscallCalculateAt($runtime, $dirfd, $path);
+
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+
+    if ($varargs !== 0) {
+        $mode = $mem->loadI32_s32($varargs);
+        $varargs += 4;
+    } else {
+        $mode = 0;
+    }
+
+    $fd = fsOpen($path, $flags, $mode);
+    if ($fd !== null) {
+        return $fd;
+    } else {
+        // no such file
+        return -44;
+    }
+}
+
+// Type: (i32, i32) -> (i32)
+function hostFunc__env____syscall_fstat64(Runtime $runtime, int $fd, int $buf): int
+{
+    $path = fsGetPathFromFd($fd);
+    \assert($path !== null);
+    syscallDoStat($runtime, fn ($path) => fsStat($path, false), $path, $buf);
+    return 0;
+}
+
+// Type: (i32, i32) -> (i32)
+function hostFunc__env____syscall_stat64(Runtime $runtime, int $path, int $buf): int
+{
+    $path = syscallGetStr($runtime, $path);
+    syscallDoStat($runtime, fn ($path) => fsStat($path, false), $path, $buf);
+    return 0;
+}
+
+// Type: (i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_newfstatat(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_newfstatat: not implemented');
+}
+
+// Type: (i32, i32) -> (i32)
+function hostFunc__env____syscall_lstat64(Runtime $runtime, int $path, int $buf): int
+{
+    $path = syscallGetStr($runtime, $path);
+    syscallDoStat($runtime, fsLstat(...), $path, $buf);
+    return 0;
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__wasi_snapshot_preview1__fd_sync(Runtime $runtime): void
+{
+    throw new \RuntimeException('wasi_snapshot_preview1::fd_sync: not implemented');
+}
+
+// Type: (i32, i32) -> (i32)
+function hostFunc__env____syscall_getcwd(Runtime $runtime, int $bufPtr, int $size): int
+{
+    if ($size === 0) {
+        return -28;
+    }
+    $cwd = getcwd();
+    \assert($cwd !== false);
+    $cwdLen = \strlen($cwd) + 1;
+    if ($size < $cwdLen) {
+        return -68;
+    }
+    copyStringToWasmMemory($runtime, $bufPtr, $cwd);
+    return $cwdLen;
+}
+
+// Type: (i32) -> ()
+function hostFunc__env__emscripten_err(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::emscripten_err: not implemented');
+}
+
+// Type: (i32, i32) -> (i32)
+function hostFunc__wasi_snapshot_preview1__fd_fdstat_get(Runtime $runtime): void
+{
+    throw new \RuntimeException('wasi_snapshot_preview1::fd_fdstat_get: not implemented');
+}
+
+// Type: (i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_mkdirat(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_mkdirat: not implemented');
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__env____syscall_pipe(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_pipe: not implemented');
+}
+
+// Type: (i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_poll(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_poll: not implemented');
+}
+
+// Type: () -> ()
+function hostFunc__env___emscripten_runtime_keepalive_clear(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::_emscripten_runtime_keepalive_clear: not implemented');
+}
+
+// Type: (i32, i32) -> ()
+function hostFunc__env____call_sighandler(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__call_sighandler: not implemented');
+}
+
+// Type: (i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_getdents64(Runtime $runtime, int $fd, int $dirp, int $count): int
+{
+    $file = fsGetVFileFromFd($fd);
+
+    if ($file->getdents === null) {
+        $file->getdents = fsReaddir($file->path);
+    }
+
+    $struct_size = 280;
+    $pos = 0;
+    $off = $file->seek(0, 1);
+
+    $idx = (int)floor($off / $struct_size);
+
+    while ($idx < \count($file->getdents) && $pos + $struct_size <= $count) {
+        $name = $file->getdents[$idx];
+        if ($name === '.') {
+            $id = fsStat($file->path, true)->ino;
+            $type = 4;
+        } elseif ($name === '..') {
+            $lookup = fsLookupParentPath($file->path);
+            $id = fsStat($lookup, true)->ino;
+            $type = 4;
+        } else {
+            $child = fsLookupChild($file->path, $name);
+            $id = fsStat($child, true)->ino;
+            $type = is_dir($child) ? 4 : (is_file($child) ? 8 : 10);
+        }
+        heap64Write($runtime, $dirp + $pos, $id);
+        heap64Write($runtime, $dirp + $pos + 8, ($idx + 1) * $struct_size);
+        heap16Write($runtime, $dirp + $pos + 16, $struct_size);
+        heap8Write($runtime, $dirp + $pos + 18, $type);
+        stringToUTF8($runtime, $name, $dirp + $pos + 19, 256);
+        $pos += $struct_size;
+        $idx += 1;
+    }
+    $file->seek($idx * $struct_size, 0);
+
+    return $pos;
+}
+
+// Type: (i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_readlinkat(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_readlinkat: not implemented');
+}
+
+// Type: (i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_renameat(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_renameat: not implemented');
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__env____syscall_rmdir(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_rmdir: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall__newselect(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall__newselect: not implemented');
+}
+
+// Type: (i32, f64) -> (i32)
+function hostFunc__env___setitimer_js(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::_setitimer_js: not implemented');
+}
+
+// Type: (i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_statfs64(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_statfs64: not implemented');
+}
+
+// Type: (i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_symlinkat(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_symlinkat: not implemented');
+}
+
+// Type: () -> (i32)
+function hostFunc__env__emscripten_get_heap_max(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::emscripten_get_heap_max: not implemented');
+}
+
+// Type: (i32, i32, i32) -> ()
+function hostFunc__env___tzset_js(Runtime $runtime): void
+{
+    // Do nothing ;)
+}
+
+// Type: (i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_unlinkat(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_unlinkat: not implemented');
+}
+
+// Type: (i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_utimensat(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_utimensat: not implemented');
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__env__emscripten_resize_heap(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::emscripten_resize_heap: not implemented');
+}
+
+// Type: () -> ()
+function hostFunc__env___emscripten_throw_longjmp(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::_emscripten_throw_longjmp: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_accept4(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_accept4: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_bind(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_bind: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_connect(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_connect: not implemented');
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__env___emscripten_lookup_name(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::_emscripten_lookup_name: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_getpeername(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_getpeername: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_getsockname(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_getsockname: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_getsockopt(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_getsockopt: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_listen(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_listen: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_recvfrom(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_recvfrom: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_sendto(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_sendto: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_socket(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_socket: not implemented');
+}
+
+// Type: (i32, i32, i32) -> (i32)
+function hostFunc__env____syscall_ftruncate64(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::__syscall_ftruncate64: not implemented');
+}
+
+// Type: (i32, i32, i32, i32) -> (i32)
+function hostFunc__wasi_snapshot_preview1__clock_time_get(Runtime $runtime, int $clk_id, int $ignored_precision_low, int $ignored_precision_high, int $ptime): int
+{
+    if ($clk_id < 0 || 3 < $clk_id) {
+        return 28;
+    }
+    if ($clk_id === 0) {
+        $now = hostFunc__env__emscripten_date_now($runtime);
+    } else {
+        $now = hostFunc__env__emscripten_get_now($runtime);
+    }
+    $nsec = round($now * 1000 * 1000);
+
+    $mem = $runtime->getExportedMemory('memory');
+    \assert($mem !== null);
+    $mem->storeI32_s32($ptime, $nsec & 0xFFFFFFFF);
+    $mem->storeI32_s32($ptime + 4, $nsec >> 32);
+
+    return 0;
+}
+
+// Type: (i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__wasi_snapshot_preview1__fd_seek(Runtime $runtime, int $fd, int $offset_low, int $offset_high, int $whence, int $newOffset): int
+{
+    $offset = $offset_low + $offset_high * 4294967296;
+    $file = fsGetVFileFromFd($fd);
+    $pos = $file->seek($offset, $whence);
+    heap64Write($runtime, $newOffset, $pos);
+
+    return 0;
+}
+
+// Type: (i32) -> (i32)
+function hostFunc__env___mktime_js(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::_mktime_js: not implemented');
+}
+
+// Type: (i32, i32, i32) -> ()
+function hostFunc__env___localtime_js(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::_localtime_js: not implemented');
+}
+
+// Type: (i32, i32, i32) -> ()
+function hostFunc__env___gmtime_js(Runtime $runtime): void
+{
+    throw new \RuntimeException('env::_gmtime_js: not implemented');
+}
+
+// Type: (i32, i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env___munmap_js(Runtime $runtime): int
+{
+    // Do nothing.
+    return 0;
+}
+
+// Type: (i32, i32, i32, i32, i32, i32, i32, i32) -> (i32)
+function hostFunc__env___mmap_js(Runtime $runtime, int $len, int $prot, int $flags, int $fd, int $offset_low, int $offset_high, int $allocated, int $addr): int
+{
+    $offset = $offset_low + $offset_high * 4294967296;
+
+    [$resultPtr, $resultAllocated] = fsMmap($runtime, $fd, $len, $offset, $prot, $flags);
+    heap32Write($runtime, $allocated, $resultAllocated);
+    heapU32Write($runtime, $addr, $resultPtr);
+
+    return 0;
+}