Support for using the GNUstep blocks runtime

.travis.yml

@@ -6,17 +6,33 @@ os:
   - osx
   - linux
 env:
-  - IOS_ARCHS=""
+  - IOS_ARCHS="" BLOCKS_RUNTIME=ObjC-compatible
 matrix:
   include:
     - os: osx
       osx_image: xcode7.2
       rust: nightly
-      env: IOS_ARCHS="i386 x86_64 armv7 armv7s aarch64"
+      env: IOS_ARCHS="i386 x86_64 armv7 armv7s aarch64" BLOCKS_RUNTIME=ObjC-compatible
+    - os: linux
+      rust: stable
+      env: IOS_ARCHS="" BLOCKS_RUNTIME=Standalone
+      addons:
+        apt:
+          packages:
+            - libblocksruntime-dev
+    - os: linux
+      rust: nightly
+      env: IOS_ARCHS="" BLOCKS_RUNTIME=Standalone
+      addons:
+        apt:
+          packages:
+            - libblocksruntime-dev
 sudo: false
 install: ./travis_install.sh
+before_script: >
+  if [ "$TRAVIS_OS_NAME" = "linux" ] && [ "$BLOCKS_RUNTIME" = "ObjC-compatible" ]; then
+    export LIBRARY_PATH=$HOME/libobjc2_staging/lib:$LIBRARY_PATH;
+    export LD_LIBRARY_PATH=$HOME/libobjc2_staging/lib:$LD_LIBRARY_PATH;
+    export CPATH=$HOME/libobjc2_staging/include:$CPATH;
+  fi
 script: ./travis_test.sh
-addons:
-  apt:
-    packages:
-      - libblocksruntime-dev

Cargo.toml

@@ -9,6 +9,7 @@ readme = "README.md"
 repository = "http://github.com/SSheldon/rust-block"
 documentation = "http://ssheldon.github.io/rust-objc/block/"
 license = "MIT"
+build = "build.rs"
 
 exclude = [
   ".gitignore",
@@ -18,6 +19,9 @@ exclude = [
   "tests-ios/**",
 ]
 
+[target.'cfg(not(any(target_os = "macos", target_os = "ios")))'.build-dependencies]
+gcc = "0.3"
+
 [dev-dependencies.objc_test_utils]
 version = "0.0"
 path = "test_utils"

build.rs

@@ -0,0 +1,63 @@
+#[cfg(not(any(target_os = "macos", target_os = "ios")))]
+extern crate gcc;
+#[cfg(not(any(target_os = "macos", target_os = "ios")))]
+use std::error::Error;
+#[cfg(not(any(target_os = "macos", target_os = "ios")))]
+use std::io::Write;
+#[cfg(not(any(target_os = "macos", target_os = "ios")))]
+use std::process::{ExitStatus,Stdio};
+#[cfg(not(any(target_os = "macos", target_os = "ios")))]
+use std::result::Result;
+#[cfg(not(any(target_os = "macos", target_os = "ios")))]
+static MINI_MAIN: &'static str = r#"
+extern void *_Block_copy(const void *aBlock);
+int main() {
+    void (*ptr)(const void*) = _Block_copy;
+    return 0;
+}"#;
+
+#[cfg(any(target_os = "macos", target_os = "ios"))]
+fn main() {
+  println!("cargo:rustc-link-lib=framework=System")
+}
+
+#[cfg(not(any(target_os = "macos", target_os = "ios")))]
+fn check_block_copy_symbol_in_lib(library: &str) -> Result<(),String> {
+    let invocation_result = gcc::Config::new()
+      .compiler("clang")
+      .get_compiler().to_command()
+      .arg(format!("-l{}", library))
+      .args(&["-x", "c"])
+      .args(&["-o", "/dev/null"])
+      .arg("-")
+      .stdin(Stdio::piped())
+      .stdout(Stdio::piped())
+      .spawn();
+    if invocation_result.is_err() {
+        return Result::Err("Could not spawn compiler".to_string())
+    }
+    let mut process = invocation_result.unwrap();
+    if let Err(why) = process.stdin.take().unwrap().write_all(MINI_MAIN.as_bytes()) {
+        return Result::Err(format!("Could not compile: {}", why.description()))
+    }
+    process.wait()
+        .or(Result::Err("Failed to compile".to_string()))
+        .and_then(| status : ExitStatus| if status.success() {
+            Result::Ok(())
+        } else {
+            Result::Err(format!("{} unavailable", library))
+        })
+}
+
+
+#[cfg(not(any(target_os = "macos", target_os = "ios")))]
+fn main() {
+    if check_block_copy_symbol_in_lib("objc").is_ok() {
+        println!("cargo:rustc-link-lib=objc")
+    } else if let Err(why) = check_block_copy_symbol_in_lib("BlocksRuntime") {
+        panic!("Could not find blocks runtime library: {}", why)
+    } else {
+        println!("cargo:rustc-link-lib=BlocksRuntime")
+    }
+
+}

src/lib.rs

@@ -56,10 +56,6 @@ use std::ptr;
 
 enum Class { }
 
-#[cfg_attr(any(target_os = "macos", target_os = "ios"),
-           link(name = "System", kind = "dylib"))]
-#[cfg_attr(not(any(target_os = "macos", target_os = "ios")),
-           link(name = "BlocksRuntime", kind = "dylib"))]
 extern {
     static _NSConcreteStackBlock: Class;
 

test_utils/block_utils.c

@@ -1,5 +1,9 @@
 #include <stdint.h>
+#if __has_include("Block.h")
 #include <Block.h>
+#elif __has_include("objc/blocks_runtime.h")
+#include <objc/blocks_runtime.h>
+#endif
 
 typedef int32_t (^IntBlock)();
 typedef int32_t (^AddBlock)(int32_t);

travis_install.sh

@@ -9,6 +9,16 @@ rust_ios_install() {
     "./${ios_stdlib}/install.sh" --prefix=$(rustc --print sysroot)
 }
 
+gnustep_install() {
+    git clone https://github.com/gnustep/libobjc2.git
+    mkdir libobjc2/build
+    cd libobjc2/build
+    export CC="clang"
+    export CXX="clang++"
+    cmake -DCMAKE_INSTALL_PREFIX:PATH=$HOME/libobjc2_staging ../
+    make install
+}
+
 for arch in $IOS_ARCHS; do
     rust_ios_install "$arch"
 done
@@ -17,3 +27,7 @@ if [ -n "$IOS_ARCHS" ]; then
     curl -LO https://github.com/SSheldon/rust-test-ios/releases/download/0.1.1/rust-test-ios
     chmod +x rust-test-ios
 fi
+
+if [ "$TRAVIS_OS_NAME" = "linux" ] && [ "$BLOCKS_RUNTIME" = "ObjC-compatible" ]; then
+    gnustep_install
+fi