Fixing get_env

src/apis/emscripten/env.rs

@@ -8,16 +8,24 @@ use std::os::raw::c_char;
 use super::utils::{copy_cstr_into_wasm, copy_terminated_array_of_cstrs};
 use crate::webassembly::Instance;
 
-/// emscripten: _getenv
-pub extern "C" fn _getenv(name_ptr: c_int, instance: &mut Instance) -> c_int {
+/// emscripten: _getenv // (name: *const char) -> *const c_char;
+pub extern "C" fn _getenv(name_ptr: c_int, instance: &mut Instance) -> u32 {
     debug!("emscripten::_getenv {}", name_ptr);
     let name = unsafe {
         let memory_name_ptr = instance.memory_offset_addr(0, name_ptr as usize) as *const c_char;
         CStr::from_ptr(memory_name_ptr).to_str().unwrap()
     };
     match host::get_env(name, instance) {
-        Ok(_) => {
-            unimplemented!();
+        Ok(env_value) => {
+            // Append null byte
+            let env_value = env_value + "\0";
+            let env_value_ptr = env_value.as_ptr() as *mut c_char;
+            let res = unsafe { copy_cstr_into_wasm(instance, env_value_ptr) };
+            // Test
+            let c_str = instance.memory_offset_addr(0, res as _) as *mut i8;
+            use std::ffi::CStr;
+            debug!("#### cstr = {:?}", unsafe { CStr::from_ptr(c_str) });
+            res
         }
         Err(_) => 0,
     }

src/apis/emscripten/linking.rs

@@ -0,0 +1,27 @@
+use crate::webassembly::Instance;
+
+// TODO: Need to implement.
+
+/// emscripten: dlopen(filename: *const c_char, flag: c_int) -> *mut c_void
+pub extern "C" fn _dlopen(filename: u32, flag: c_int) -> u32 {
+    debug!("emscripten::_dlopen");
+    -1
+}
+
+/// emscripten: dlclose(handle: *mut c_void) -> c_int
+pub extern "C" fn _dlclose(filename: u32) -> u32 {
+    debug!("emscripten::_dlclose");
+    -1
+}
+
+/// emscripten: dlsym(handle: *mut c_void, symbol: *const c_char) -> *mut c_void
+pub extern "C" fn _dlsym(filepath: u32, symbol: u32) -> u32 {
+    debug!("emscripten::_dlerror");
+    -1
+}
+
+/// emscripten: dlerror() -> *mut c_char
+pub extern "C" fn _dlerror() -> u32 {
+    debug!("emscripten::_dlerror");
+    -1
+}

src/apis/emscripten/mod.rs

@@ -349,6 +349,11 @@ pub fn generate_emscripten_env<'a, 'b>() -> ImportObject<&'a str, &'b str> {
         "___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",
@@ -511,7 +516,7 @@ pub fn generate_emscripten_env<'a, 'b>() -> ImportObject<&'a str, &'b str> {
     mock_external!(import_object, ___syscall66);
     // mock_external!(import_object, ___syscall64);
     // mock_external!(import_object, ___syscall63);
-    mock_external!(import_object, ___syscall60);
+    // mock_external!(import_object, ___syscall60);
     // mock_external!(import_object, ___syscall54);
     // mock_external!(import_object, ___syscall39);
     mock_external!(import_object, ___syscall38);
@@ -543,6 +548,10 @@ pub fn generate_emscripten_env<'a, 'b>() -> ImportObject<&'a str, &'b str> {
     // 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
 }

src/apis/emscripten/syscalls.rs

@@ -72,7 +72,7 @@ use libc::{
     F_GETFD,
 };
 
-// Linking to functions that are provided by rust libc
+// Linking to functions that are not provided by rust libc
 #[cfg(target_os = "macos")]
 #[link(name = "c")]
 extern {

src/apis/emscripten/time.rs

@@ -135,7 +135,7 @@ pub extern "C" fn _asctime(time: u32, instance: &mut Instance) -> u32 {
         let time_str_ptr = fmt_time(time, instance);
         copy_cstr_into_wasm(instance, time_str_ptr)
 
-        // let c_str = instance.memory_offset_addr(0, time_str_offset as _) as *mut i8;
+        // let c_str = instance.memory_offset_addr(0, res as _) as *mut i8;
         // use std::ffi::CStr;
         // debug!("#### cstr = {:?}", CStr::from_ptr(c_str));
     }
@@ -153,7 +153,7 @@ pub extern "C" fn _asctime_r(time: u32, buf: u32, instance: &mut Instance) -> u3
         let time_str_ptr = fmt_time(time, instance);
         write_to_buf(time_str_ptr, buf, 26, instance)
 
-        // let c_str = instance.memory_offset_addr(0, time_str_offset as _) as *mut i8;
+        // let c_str = instance.memory_offset_addr(0, res as _) as *mut i8;
         // use std::ffi::CStr;
         // debug!("#### cstr = {:?}", CStr::from_ptr(c_str));
     }

src/apis/emscripten/utils.rs

@@ -29,20 +29,25 @@ pub fn write_to_buf(string: *const c_char, buf: u32, max: u32, instance: &Instan
     buf
 }
 
+/// This function expects nullbyte to be appended.
 pub unsafe fn copy_cstr_into_wasm(instance: &mut Instance, cstr: *const c_char) -> u32 {
     let s = CStr::from_ptr(cstr).to_str().unwrap();
     let cstr_len = s.len();
+    debug!("### 1!");
     let space_offset = (instance.emscripten_data.as_ref().unwrap().malloc)((cstr_len as i32) + 1, instance);
+    debug!("### 2!");
     let raw_memory = instance.memory_offset_addr(0, space_offset as _) as *mut u8;
     let slice = slice::from_raw_parts_mut(raw_memory, cstr_len);
 
     for (byte, loc) in s.bytes().zip(slice.iter_mut()) {
         *loc = byte;
     }
+    debug!("### KABOOM 10!");
 
     // TODO: Appending null byte won't work, because there is CStr::from_ptr(cstr)
     //      at the top that crashes when there is no null byte
     *raw_memory.add(cstr_len) = 0;
+    debug!("### KABOOM 15!");
 
     space_offset
 }