From c1a9c8bcff5191ad8c3dcff4209cbcd6af6633ba Mon Sep 17 00:00:00 2001
From: Ivan Enderlin <ivan@mnt.io>
Date: Fri, 18 Sep 2020 14:36:46 +0200
Subject: [PATCH] feat(c-api) Add `wat2wasm` to the `wasm-c-api` module.

---
 Makefile                        | 12 ++++++------
 lib/c-api/Cargo.toml            |  2 ++
 lib/c-api/src/wasm_c_api/mod.rs | 17 +++++++++++++++++
 lib/c-api/wasmer_wasm.h         |  5 +++++
 4 files changed, 30 insertions(+), 6 deletions(-)

diff --git a/Makefile b/Makefile
index 3cb273b8abb..b4217370ae7 100644
--- a/Makefile
+++ b/Makefile
@@ -76,15 +76,15 @@ build-capi: build-capi-cranelift
 
 build-capi-singlepass:
 	cargo build --manifest-path lib/c-api/Cargo.toml --release \
-		--no-default-features --features jit,singlepass,wasi
+		--no-default-features --features wat,jit,singlepass,wasi
 
 build-capi-cranelift:
 	cargo build --manifest-path lib/c-api/Cargo.toml --release \
-		--no-default-features --features jit,cranelift,wasi
+		--no-default-features --features wat,jit,cranelift,wasi
 
 build-capi-llvm:
 	cargo build --manifest-path lib/c-api/Cargo.toml --release \
-		--no-default-features --features jit,llvm,wasi
+		--no-default-features --features wat,jit,llvm,wasi
 
 
 ###########
@@ -112,15 +112,15 @@ test-packages:
 
 test-capi-singlepass: build-capi-singlepass
 	cargo test --manifest-path lib/c-api/Cargo.toml --release \
-		--no-default-features --features jit,singlepass,wasi -- --nocapture
+		--no-default-features --features wat,jit,singlepass,wasi -- --nocapture
 
 test-capi-cranelift: build-capi-cranelift
 	cargo test --manifest-path lib/c-api/Cargo.toml --release \
-		--no-default-features --features jit,cranelift,wasi -- --nocapture
+		--no-default-features --features wat,jit,cranelift,wasi -- --nocapture
 
 test-capi-llvm: build-capi-llvm
 	cargo test --manifest-path lib/c-api/Cargo.toml --release \
-		--no-default-features --features jit,llvm,wasi -- --nocapture
+		--no-default-features --features wat,jit,llvm,wasi -- --nocapture
 
 test-capi: test-capi-singlepass test-capi-cranelift test-capi-llvm
 
diff --git a/lib/c-api/Cargo.toml b/lib/c-api/Cargo.toml
index bc525a83199..e438cd36986 100644
--- a/lib/c-api/Cargo.toml
+++ b/lib/c-api/Cargo.toml
@@ -40,9 +40,11 @@ paste = "0.1"
 
 [features]
 default = [
+    "wat",
     "cranelift",
     "wasi",
 ]
+wat = ["wasmer/wat"]
 wasi = ["wasmer-wasi", "typetag", "serde"]
 engine = []
 jit = [
diff --git a/lib/c-api/src/wasm_c_api/mod.rs b/lib/c-api/src/wasm_c_api/mod.rs
index 8e14c34cd2f..673d65f702b 100644
--- a/lib/c-api/src/wasm_c_api/mod.rs
+++ b/lib/c-api/src/wasm_c_api/mod.rs
@@ -24,6 +24,23 @@ use wasmer::{
 #[cfg(feature = "jit")]
 use wasmer_engine_jit::JIT;
 
+/// Parses in-memory bytes as either the WAT format, or a binary Wasm
+/// module. This is wasmer-specific.
+#[cfg(feature = "wat")]
+#[no_mangle]
+pub unsafe extern "C" fn wat2wasm(wat: &wasm_byte_vec_t, wasm: &mut wasm_byte_vec_t) -> Option<()> {
+    let wat: &[u8] = slice::from_raw_parts_mut(wat.data, wat.size);
+
+    let result = c_try!(wasmer::wat2wasm(wat));
+    let mut result = result.into_owned();
+    wasm.size = result.len();
+    wasm.data = result.as_mut_ptr();
+
+    mem::forget(result);
+
+    Some(())
+}
+
 /// this can be a wasmer-specific type with wasmer-specific functions for manipulating it
 #[repr(C)]
 pub struct wasm_config_t {}
diff --git a/lib/c-api/wasmer_wasm.h b/lib/c-api/wasmer_wasm.h
index 56260c91fc4..7374c998245 100644
--- a/lib/c-api/wasmer_wasm.h
+++ b/lib/c-api/wasmer_wasm.h
@@ -21,6 +21,7 @@
 
 // Used to build a `wasi_env_t`.
 typedef struct wasi_config_t wasi_config_t;
+
 // This type is passed to the WASI host functions owns the data core to the
 // functioning of WASI.
 typedef struct wasi_env_t wasi_env_t;
@@ -142,4 +143,8 @@ int wasmer_last_error_length();
  */
 int wasmer_last_error_message(char* buffer, int length);
 
+// Parses in-memory bytes as either the WAT format, or a binary Wasm
+// module. This is wasmer-specific.
+void wat2wasm(wasm_byte_vec_t* wat, wasm_byte_vec_t* wasm);
+
 #endif /* WASMER_WASM_H */