Added tips about dynamic libraries (nervosnetwork#117)

* Added tips about dynamic libraries

* Use lazy_static

contracts/ckb-std-tests/Cargo.toml

@@ -9,4 +9,6 @@ edition = "2021"
 ckb-std = { path = "../../", features = ["build-with-clang", "dlopen-c", "log"] }
 blake2b-ref = { version = "0.3", default-features = false }
 bytes = { version = "1.7", default-features = false }
+lazy_static = { version = "1.5.0", default-features = false, features = ["spin_no_std"] }
 log = { version = "0.4", default-features = false }
+spin = { version = "0.9" }

contracts/ckb-std-tests/src/entry.rs

@@ -22,6 +22,10 @@ use ckb_std::{dynamic_loading, dynamic_loading_c_impl};
 use core::ffi::c_void;
 #[cfg(target_arch = "riscv64")]
 use core::mem::size_of_val;
+#[cfg(target_arch = "riscv64")]
+use lazy_static::lazy_static;
+#[cfg(target_arch = "riscv64")]
+use spin::Mutex;
 
 fn new_blake2b() -> Blake2b {
     const CKB_HASH_PERSONALIZATION: &[u8] = b"ckb-default-hash";
@@ -795,6 +799,19 @@ fn test_log() {
     ckb_std::log::error!("this is error");
 }
 
+#[cfg(target_arch = "riscv64")]
+lazy_static! {
+    // Context should not be dropped.
+    static ref old_context: Mutex<ContextTypeOld> = {
+        #[allow(deprecated)]
+        Mutex::new(unsafe { ContextTypeOld::new() })
+    };
+    // Context should not be dropped.
+    static ref new_context: Mutex<ContextType> = {
+        Mutex::new(unsafe { ContextType::new() })
+    };
+}
+
 pub fn main() -> Result<(), Error> {
     test_basic();
     test_load_data();
@@ -805,6 +822,11 @@ pub fn main() -> Result<(), Error> {
     test_query();
     test_calc_data_hash();
 
+    #[cfg(target_arch = "riscv64")]
+    test_dynamic_loading(&mut old_context.lock());
+    #[cfg(target_arch = "riscv64")]
+    test_dynamic_loading_c_impl(&mut new_context.lock());
+
     test_vm_version();
     test_current_cycles();
     test_since();
@@ -815,15 +837,5 @@ pub fn main() -> Result<(), Error> {
         test_log();
     }
 
-    #[cfg(target_arch = "riscv64")]
-    unsafe {
-        let mut context = ContextType::new();
-        #[allow(deprecated)]
-        let mut old_context = ContextTypeOld::new();
-
-        test_dynamic_loading(&mut old_context);
-        test_dynamic_loading_c_impl(&mut context);
-    }
-
     Ok(())
 }

test/simulator/Cargo.toml

@@ -19,7 +19,9 @@ path = "src/exec_callee.rs"
 ckb-std = { path = "../..", default-features=false, features = ["allocator", "calc-hash", "ckb-types", "libc", "native-simulator"] }
 blake2b-ref = { version = "0.3", default-features = false }
 bytes = { version = "1.6.0", default-features = false }
+lazy_static = { version = "1.5.0", default-features = false, features = ["spin_no_std"] }
 log = { version = "0.4.17", default-features = false }
+spin = { version = "0.9" }
 
 [dev-dependencies]
 libloading = "0.8.4"