From 5680d33dd91af30d085ecd991e74dd56e367e8ea Mon Sep 17 00:00:00 2001
From: DjDeveloper <43033058+DjDeveloperr@users.noreply.github.com>
Date: Tue, 11 Jan 2022 11:51:16 +0530
Subject: [PATCH] feat(ext/ffi): support alias names for symbol definitions
 (#13090)

---
 cli/dts/lib.deno.unstable.d.ts      |  2 ++
 ext/ffi/lib.rs                      | 11 ++++++++---
 test_ffi/tests/integration_tests.rs |  2 ++
 test_ffi/tests/test.js              | 25 ++++++++++++++++++++-----
 4 files changed, 32 insertions(+), 8 deletions(-)

diff --git a/cli/dts/lib.deno.unstable.d.ts b/cli/dts/lib.deno.unstable.d.ts
index a371f37d1b..4b43c181be 100644
--- a/cli/dts/lib.deno.unstable.d.ts
+++ b/cli/dts/lib.deno.unstable.d.ts
@@ -126,6 +126,8 @@ declare namespace Deno {
     Result extends NativeType = NativeType,
     NonBlocking extends boolean = boolean,
   > {
+    /** Name of the symbol, defaults to the key name in symbols object. */
+    name?: string;
     parameters: Parameters;
     result: Result;
     /** When true, function calls will run on a dedicated blocking thread and will return a Promise resolving to the `result`. */
diff --git a/ext/ffi/lib.rs b/ext/ffi/lib.rs
index c38788d30f..2a6799b5ff 100644
--- a/ext/ffi/lib.rs
+++ b/ext/ffi/lib.rs
@@ -78,13 +78,17 @@ impl Resource for DynamicLibraryResource {
 impl DynamicLibraryResource {
   fn register(
     &mut self,
-    symbol: String,
+    name: String,
     foreign_fn: ForeignFunction,
   ) -> Result<(), AnyError> {
+    let symbol = match &foreign_fn.name {
+      Some(symbol) => symbol,
+      None => &name,
+    };
     // By default, Err returned by this function does not tell
     // which symbol wasn't exported. So we'll modify the error
     // message to include the name of symbol.
-    let fn_ptr = match unsafe { self.lib.symbol::<*const c_void>(&symbol) } {
+    let fn_ptr = match unsafe { self.lib.symbol::<*const c_void>(symbol) } {
       Ok(value) => Ok(value),
       Err(err) => Err(generic_error(format!(
         "Failed to register symbol {}: {}",
@@ -103,7 +107,7 @@ impl DynamicLibraryResource {
     );
 
     self.symbols.insert(
-      symbol,
+      name,
       Symbol {
         cif,
         ptr,
@@ -337,6 +341,7 @@ impl From<U32x2> for u64 {
 #[derive(Deserialize, Debug)]
 #[serde(rename_all = "camelCase")]
 struct ForeignFunction {
+  name: Option<String>,
   parameters: Vec<NativeType>,
   result: NativeType,
 }
diff --git a/test_ffi/tests/integration_tests.rs b/test_ffi/tests/integration_tests.rs
index 39550925fa..91de4412e0 100644
--- a/test_ffi/tests/integration_tests.rs
+++ b/test_ffi/tests/integration_tests.rs
@@ -63,6 +63,8 @@ fn basic() {
     579\n\
     579.9119873046875\n\
     579.912\n\
+    After sleep_blocking\n\
+    true\n\
     Before\n\
     true\n\
     After\n\
diff --git a/test_ffi/tests/test.js b/test_ffi/tests/test.js
index 2f04659215..7ebcf4460d 100644
--- a/test_ffi/tests/test.js
+++ b/test_ffi/tests/test.js
@@ -32,7 +32,11 @@ assertThrows(
 );
 
 const dylib = Deno.dlopen(libPath, {
-  "print_something": { parameters: [], result: "void" },
+  "printSomething": {
+    name: "print_something",
+    parameters: [],
+    result: "void",
+  },
   "print_buffer": { parameters: ["pointer", "usize"], result: "void" },
   "print_buffer2": {
     parameters: ["pointer", "usize", "pointer", "usize"],
@@ -49,7 +53,13 @@ const dylib = Deno.dlopen(libPath, {
   "add_f32": { parameters: ["f32", "f32"], result: "f32" },
   "add_f64": { parameters: ["f64", "f64"], result: "f64" },
   "fill_buffer": { parameters: ["u8", "pointer", "usize"], result: "void" },
-  "sleep_blocking": { parameters: ["u64"], result: "void", nonblocking: true },
+  "sleep_nonblocking": {
+    name: "sleep_blocking",
+    parameters: ["u64"],
+    result: "void",
+    nonblocking: true,
+  },
+  "sleep_blocking": { parameters: ["u64"], result: "void" },
   "nonblocking_buffer": {
     parameters: ["pointer", "usize"],
     result: "void",
@@ -57,7 +67,7 @@ const dylib = Deno.dlopen(libPath, {
   },
 });
 
-dylib.symbols.print_something();
+dylib.symbols.printSomething();
 const buffer = new Uint8Array([1, 2, 3, 4, 5, 6, 7, 8]);
 const buffer2 = new Uint8Array([9, 10]);
 dylib.symbols.print_buffer(buffer, buffer.length);
@@ -150,8 +160,13 @@ dylib.symbols.nonblocking_buffer(buffer3, buffer3.length).then(() => {
 });
 await promise;
 
-const start = performance.now();
-dylib.symbols.sleep_blocking(100).then(() => {
+let start = performance.now();
+dylib.symbols.sleep_blocking(100);
+console.log("After sleep_blocking");
+console.log(performance.now() - start >= 100);
+
+start = performance.now();
+dylib.symbols.sleep_nonblocking(100).then(() => {
   console.log("After");
   console.log(performance.now() - start >= 100);
   // Close after task is complete.