wasmer/src/apis/emscripten/mod.rs

/// NOTE: TODO: These emscripten api implementation only support wasm32 for now because they assume offsets are u32
use crate::webassembly::{ImportObject, ImportValue, LinearMemory};
use byteorder::{ByteOrder, LittleEndian};
use std::mem;

// EMSCRIPTEN APIS
mod env;
mod errno;
mod exception;
mod io;
mod lock;
mod math;
mod memory;
mod nullfunc;
mod process;
mod signal;
mod storage;
mod syscalls;
mod time;
mod utils;
mod varargs;

pub use self::storage::align_memory;
pub use self::utils::{allocate_cstr_on_stack, allocate_on_stack, is_emscripten_module};

// TODO: Magic number - how is this calculated?
const TOTAL_STACK: u32 = 5_242_880;
// TODO: Magic number - how is this calculated?
const DYNAMICTOP_PTR_DIFF: u32 = 1088;
// TODO: make this variable
const STATIC_BUMP: u32 = 215_536;

fn stacktop(static_bump: u32) -> u32 {
    align_memory(dynamictop_ptr(static_bump) + 4)
}

fn stack_max(static_bump: u32) -> u32 {
    stacktop(static_bump) + TOTAL_STACK
}

fn dynamic_base(static_bump: u32) -> u32 {
    align_memory(stack_max(static_bump))
}

fn dynamictop_ptr(static_bump: u32) -> u32 {
    static_bump + DYNAMICTOP_PTR_DIFF
}

pub fn emscripten_set_up_memory(memory: &mut LinearMemory) {
    let dynamictop_ptr = dynamictop_ptr(STATIC_BUMP) as usize;
    let dynamictop_ptr_offset = dynamictop_ptr + mem::size_of::<u32>();

    // println!("value = {:?}");

    // We avoid failures of setting the u32 in our memory if it's out of bounds
    if dynamictop_ptr_offset > memory.len() {
        return; // TODO: We should panic instead?
    }

    // debug!("###### dynamic_base = {:?}", dynamic_base(STATIC_BUMP));
    // debug!("###### dynamictop_ptr = {:?}", dynamictop_ptr);
    // debug!("###### dynamictop_ptr_offset = {:?}", dynamictop_ptr_offset);

    let mem = &mut memory[dynamictop_ptr..dynamictop_ptr_offset];
    LittleEndian::write_u32(mem, dynamic_base(STATIC_BUMP));
}

macro_rules! mock_external {
    ($import:ident, $name:ident) => {{
        extern "C" fn _mocked_fn() -> i32 {
            debug!("emscripten::{} <mock>", stringify!($name));
            -1
        }
        $import.set("env", stringify!($name), ImportValue::Func(_mocked_fn as _));
    }};
}

pub fn generate_emscripten_env<'a, 'b>() -> ImportObject<&'a str, &'b str> {
    let mut import_object = ImportObject::new();
    // Globals
    import_object.set(
        "env",
        "STACKTOP",
        ImportValue::Global(stacktop(STATIC_BUMP) as _),
    );
    import_object.set(
        "env",
        "STACK_MAX",
        ImportValue::Global(stack_max(STATIC_BUMP) as _),
    );
    import_object.set(
        "env",
        "DYNAMICTOP_PTR",
        ImportValue::Global(dynamictop_ptr(STATIC_BUMP) as _),
    );
    import_object.set(
        "global",
        "Infinity",
        ImportValue::Global(std::f64::INFINITY.to_bits() as _),
    );
    import_object.set(
        "global",
        "NaN",
        ImportValue::Global(std::f64::NAN.to_bits() as _),
    );
    import_object.set("env", "tableBase", ImportValue::Global(0));
    // Print functions
    import_object.set("env", "printf", ImportValue::Func(io::printf as _));
    import_object.set("env", "putchar", ImportValue::Func(io::putchar as _));
    // Lock
    import_object.set("env", "___lock", ImportValue::Func(lock::___lock as _));
    import_object.set("env", "___unlock", ImportValue::Func(lock::___unlock as _));
    import_object.set("env", "___wait", ImportValue::Func(lock::___wait as _));
    // Env
    import_object.set("env", "_getenv", ImportValue::Func(env::_getenv as _));
    import_object.set("env", "_getpwnam", ImportValue::Func(env::_getpwnam as _));
    import_object.set("env", "_getgrnam", ImportValue::Func(env::_getgrnam as _));
    import_object.set(
        "env",
        "___buildEnvironment",
        ImportValue::Func(env::___build_environment as _),
    );
    // Errno
    import_object.set(
        "env",
        "___setErrNo",
        ImportValue::Func(errno::___seterrno as _),
    );
    // Syscalls
    import_object.set(
        "env",
        "___syscall1",
        ImportValue::Func(syscalls::___syscall1 as _),
    );
    import_object.set(
        "env",
        "___syscall3",
        ImportValue::Func(syscalls::___syscall3 as _),
    );
    import_object.set(
        "env",
        "___syscall4",
        ImportValue::Func(syscalls::___syscall4 as _),
    );
    import_object.set(
        "env",
        "___syscall5",
        ImportValue::Func(syscalls::___syscall5 as _),
    );
    import_object.set(
        "env",
        "___syscall6",
        ImportValue::Func(syscalls::___syscall6 as _),
    );
    import_object.set(
        "env",
        "___syscall12",
        ImportValue::Func(syscalls::___syscall12 as _),
    );
    import_object.set(
        "env",
        "___syscall20",
        ImportValue::Func(syscalls::___syscall20 as _),
    );
    import_object.set(
        "env",
        "___syscall39",
        ImportValue::Func(syscalls::___syscall39 as _),
    );
    import_object.set(
        "env",
        "___syscall40",
        ImportValue::Func(syscalls::___syscall40 as _),
    );
    import_object.set(
        "env",
        "___syscall54",
        ImportValue::Func(syscalls::___syscall54 as _),
    );
    import_object.set(
        "env",
        "___syscall57",
        ImportValue::Func(syscalls::___syscall57 as _),
    );
    import_object.set(
        "env",
        "___syscall63",
        ImportValue::Func(syscalls::___syscall63 as _),
    );
    import_object.set(
        "env",
        "___syscall64",
        ImportValue::Func(syscalls::___syscall64 as _),
    );
    import_object.set(
        "env",
        "___syscall102",
        ImportValue::Func(syscalls::___syscall102 as _),
    );
    import_object.set(
        "env",
        "___syscall114",
        ImportValue::Func(syscalls::___syscall114 as _),
    );
    import_object.set(
        "env",
        "___syscall122",
        ImportValue::Func(syscalls::___syscall122 as _),
    );
    import_object.set(
        "env",
        "___syscall140",
        ImportValue::Func(syscalls::___syscall140 as _),
    );
    import_object.set(
        "env",
        "___syscall142",
        ImportValue::Func(syscalls::___syscall142 as _),
    );
    import_object.set(
        "env",
        "___syscall145",
        ImportValue::Func(syscalls::___syscall145 as _),
    );
    import_object.set(
        "env",
        "___syscall146",
        ImportValue::Func(syscalls::___syscall146 as _),
    );
    import_object.set(
        "env",
        "___syscall180",
        ImportValue::Func(syscalls::___syscall180 as _),
    );
    import_object.set(
        "env",
        "___syscall181",
        ImportValue::Func(syscalls::___syscall181 as _),
    );
    import_object.set(
        "env",
        "___syscall192",
        ImportValue::Func(syscalls::___syscall192 as _),
    );
    import_object.set(
        "env",
        "___syscall195",
        ImportValue::Func(syscalls::___syscall195 as _),
    );
    import_object.set(
        "env",
        "___syscall197",
        ImportValue::Func(syscalls::___syscall197 as _),
    );
    import_object.set(
        "env",
        "___syscall201",
        ImportValue::Func(syscalls::___syscall201 as _),
    );
    import_object.set(
        "env",
        "___syscall202",
        ImportValue::Func(syscalls::___syscall202 as _),
    );
    import_object.set(
        "env",
        "___syscall212",
        ImportValue::Func(syscalls::___syscall212 as _),
    );
    import_object.set(
        "env",
        "___syscall221",
        ImportValue::Func(syscalls::___syscall221 as _),
    );
    import_object.set(
        "env",
        "___syscall330",
        ImportValue::Func(syscalls::___syscall330 as _),
    );
    import_object.set(
        "env",
        "___syscall340",
        ImportValue::Func(syscalls::___syscall340 as _),
    );
    // Process
    import_object.set("env", "abort", ImportValue::Func(process::em_abort as _));
    import_object.set("env", "_abort", ImportValue::Func(process::_abort as _));
    import_object.set(
        "env",
        "abortStackOverflow",
        ImportValue::Func(process::abort_stack_overflow as _),
    );
    import_object.set(
        "env",
        "_llvm_trap",
        ImportValue::Func(process::_llvm_trap as _),
    );
    import_object.set("env", "_fork", ImportValue::Func(process::_fork as _));
    import_object.set("env", "_exit", ImportValue::Func(process::_exit as _));
    import_object.set("env", "_system", ImportValue::Func(process::_system as _));
    import_object.set("env", "_popen", ImportValue::Func(process::_popen as _));
    // Signal
    import_object.set(
        "env",
        "_sigemptyset",
        ImportValue::Func(signal::_sigemptyset as _),
    );
    import_object.set(
        "env",
        "_sigaddset",
        ImportValue::Func(signal::_sigaddset as _),
    );
    import_object.set(
        "env",
        "_sigprocmask",
        ImportValue::Func(signal::_sigprocmask as _),
    );
    import_object.set(
        "env",
        "_sigaction",
        ImportValue::Func(signal::_sigaction as _),
    );
    import_object.set("env", "_signal", ImportValue::Func(signal::_signal as _));
    // Memory
    import_object.set(
        "env",
        "abortOnCannotGrowMemory",
        ImportValue::Func(memory::abort_on_cannot_grow_memory as _),
    );
    import_object.set(
        "env",
        "_emscripten_memcpy_big",
        ImportValue::Func(memory::_emscripten_memcpy_big as _),
    );
    import_object.set(
        "env",
        "enlargeMemory",
        ImportValue::Func(memory::enlarge_memory as _),
    );
    import_object.set(
        "env",
        "getTotalMemory",
        ImportValue::Func(memory::get_total_memory as _),
    );
    import_object.set(
        "env",
        "___map_file",
        ImportValue::Func(memory::___map_file as _),
    );
    // Exception
    import_object.set(
        "env",
        "___cxa_allocate_exception",
        ImportValue::Func(exception::___cxa_allocate_exception as _),
    );
    import_object.set(
        "env",
        "___cxa_allocate_exception",
        ImportValue::Func(exception::___cxa_throw as _),
    );
    import_object.set(
        "env",
        "___cxa_throw",
        ImportValue::Func(exception::___cxa_throw as _),
    );
    // NullFuncs
    import_object.set(
        "env",
        "nullFunc_ii",
        ImportValue::Func(nullfunc::nullfunc_ii as _),
    );
    import_object.set(
        "env",
        "nullFunc_iii",
        ImportValue::Func(nullfunc::nullfunc_iii as _),
    );
    import_object.set(
        "env",
        "nullFunc_iiii",
        ImportValue::Func(nullfunc::nullfunc_iiii as _),
    );
    import_object.set(
        "env",
        "nullFunc_iiiii",
        ImportValue::Func(nullfunc::nullfunc_iiiii as _),
    );
    import_object.set(
        "env",
        "nullFunc_iiiiii",
        ImportValue::Func(nullfunc::nullfunc_iiiiii as _),
    );
    import_object.set(
        "env",
        "nullFunc_v",
        ImportValue::Func(nullfunc::nullfunc_v as _),
    );
    import_object.set(
        "env",
        "nullFunc_vi",
        ImportValue::Func(nullfunc::nullfunc_vi as _),
    );
    import_object.set(
        "env",
        "nullFunc_vii",
        ImportValue::Func(nullfunc::nullfunc_vii as _),
    );
    import_object.set(
        "env",
        "nullFunc_viii",
        ImportValue::Func(nullfunc::nullfunc_viii as _),
    );
    import_object.set(
        "env",
        "nullFunc_viiii",
        ImportValue::Func(nullfunc::nullfunc_viiii as _),
    );
    import_object.set(
        "env",
        "nullFunc_viiiii",
        ImportValue::Func(nullfunc::nullfunc_viiiii as _),
    );
    import_object.set(
        "env",
        "nullFunc_viiiiii",
        ImportValue::Func(nullfunc::nullfunc_viiiiii as _),
    );
    // Time
    import_object.set(
        "env",
        "_gettimeofday",
        ImportValue::Func(time::_gettimeofday as _),
    );
    import_object.set(
        "env",
        "_clock_gettime",
        ImportValue::Func(time::_clock_gettime as _),
    );
    import_object.set(
        "env",
        "___clock_gettime",
        ImportValue::Func(time::___clock_gettime as _),
    );
    import_object.set("env", "_clock", ImportValue::Func(time::_clock as _));
    import_object.set("env", "_difftime", ImportValue::Func(time::_difftime as _));
    import_object.set("env", "_asctime", ImportValue::Func(time::_asctime as _));
    import_object.set(
        "env",
        "_asctime_r",
        ImportValue::Func(time::_asctime_r as _),
    );
    import_object.set(
        "env",
        "_localtime",
        ImportValue::Func(time::_localtime as _),
    );
    import_object.set("env", "_time", ImportValue::Func(time::_time as _));
    import_object.set("env", "_strftime", ImportValue::Func(time::_strftime as _));
    import_object.set(
        "env",
        "_localtime_r",
        ImportValue::Func(time::_localtime_r as _),
    );
    import_object.set(
        "env",
        "_getpagesize",
        ImportValue::Func(env::_getpagesize as _),
    );
    import_object.set("env", "_sysconf", ImportValue::Func(env::_sysconf as _));
    // Math
    import_object.set(
        "env",
        "_llvm_log10_f64",
        ImportValue::Func(math::_llvm_log10_f64 as _),
    );
    import_object.set(
        "env",
        "_llvm_log2_f64",
        ImportValue::Func(math::_llvm_log2_f64 as _),
    );
    import_object.set("asm2wasm", "f64-rem", ImportValue::Func(math::f64_rem as _));

    mock_external!(import_object, _waitpid);
    mock_external!(import_object, _utimes);
    mock_external!(import_object, _usleep);
    // mock_external!(import_object, _time);
    // mock_external!(import_object, _sysconf);
    // mock_external!(import_object, _strftime);
    mock_external!(import_object, _sigsuspend);
    // mock_external!(import_object, _sigprocmask);
    // mock_external!(import_object, _sigemptyset);
    // mock_external!(import_object, _sigaddset);
    // mock_external!(import_object, _sigaction);
    mock_external!(import_object, _setitimer);
    mock_external!(import_object, _setgroups);
    mock_external!(import_object, _setgrent);
    mock_external!(import_object, _sem_wait);
    mock_external!(import_object, _sem_post);
    mock_external!(import_object, _sem_init);
    mock_external!(import_object, _sched_yield);
    mock_external!(import_object, _raise);
    mock_external!(import_object, _mktime);
    // mock_external!(import_object, _localtime_r);
    // mock_external!(import_object, _localtime);
    mock_external!(import_object, _llvm_stacksave);
    mock_external!(import_object, _llvm_stackrestore);
    mock_external!(import_object, _kill);
    mock_external!(import_object, _gmtime_r);
    // mock_external!(import_object, _gettimeofday);
    // mock_external!(import_object, _getpagesize);
    mock_external!(import_object, _getgrent);
    mock_external!(import_object, _getaddrinfo);
    // mock_external!(import_object, _fork);
    // mock_external!(import_object, _exit);
    mock_external!(import_object, _execve);
    mock_external!(import_object, _endgrent);
    // mock_external!(import_object, _clock_gettime);
    mock_external!(import_object, ___syscall97);
    mock_external!(import_object, ___syscall91);
    mock_external!(import_object, ___syscall85);
    mock_external!(import_object, ___syscall75);
    mock_external!(import_object, ___syscall66);
    // mock_external!(import_object, ___syscall64);
    // mock_external!(import_object, ___syscall63);
    // mock_external!(import_object, ___syscall60);
    // mock_external!(import_object, ___syscall54);
    // mock_external!(import_object, ___syscall39);
    mock_external!(import_object, ___syscall38);
    // mock_external!(import_object, ___syscall340);
    mock_external!(import_object, ___syscall334);
    mock_external!(import_object, ___syscall300);
    mock_external!(import_object, ___syscall295);
    mock_external!(import_object, ___syscall272);
    mock_external!(import_object, ___syscall268);
    // mock_external!(import_object, ___syscall221);
    mock_external!(import_object, ___syscall220);
    // mock_external!(import_object, ___syscall212);
    // mock_external!(import_object, ___syscall201);
    mock_external!(import_object, ___syscall199);
    // mock_external!(import_object, ___syscall197);
    mock_external!(import_object, ___syscall196);
    // mock_external!(import_object, ___syscall195);
    mock_external!(import_object, ___syscall194);
    mock_external!(import_object, ___syscall191);
    // mock_external!(import_object, ___syscall181);
    // mock_external!(import_object, ___syscall180);
    mock_external!(import_object, ___syscall168);
    // mock_external!(import_object, ___syscall146);
    // mock_external!(import_object, ___syscall145);
    // mock_external!(import_object, ___syscall142);
    mock_external!(import_object, ___syscall140);
    // mock_external!(import_object, ___syscall122);
    // mock_external!(import_object, ___syscall102);
    // mock_external!(import_object, ___syscall20);
    mock_external!(import_object, ___syscall15);
    mock_external!(import_object, ___syscall10);
    mock_external!(import_object, _dlopen);
    mock_external!(import_object, _dlclose);
    mock_external!(import_object, _dlsym);
    mock_external!(import_object, _dlerror);

    import_object
}