Merge #2058

2058: fix(c-api) `wasi_version_t` wasn't bound correctly to C r=Hywan a=Hywan # Description Because the enum variants weren't in uppercase _and_ because one variant (`InvalidVersion`) has a non-literal value, `cbindgen` was ignoring the variants. This patch fixes that. It's not a breaking changes since the WASI version constants weren't present in the `wasmer_wasm.h` file before. Note: `u32::max_value()` is soft-deprecated, we should use `u32::MAX` instead. Notice that none of them works with `cbindgen`, so I've hardcoded the value of `u32::MAX` here. # Review - [x] Add a short description of the the change to the CHANGELOG.md file Co-authored-by: Ivan Enderlin <[email protected]>
wasmerio · Jan 27, 2021 · 945fa81 · 945fa81
2 parents cfc8f04 + 276537a
commit 945fa81
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diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -19,6 +19,7 @@
 - [#2056](https://github.com/wasmerio/wasmer/pull/2056) Change back to depend on the `enumset` crate instead of `wasmer_enumset`
 
 ### Fixed
+- [#2058](https://github.com/wasmerio/wasmer/pull/2058) Expose WASI versions to C correctly.
 - [#2044](https://github.com/wasmerio/wasmer/pull/2044) Do not build C headers on docs.rs.
 
 ## 1.0.1 - 2021-01-12

diff --git a/lib/c-api/src/wasm_c_api/wasi/mod.rs b/lib/c-api/src/wasm_c_api/wasi/mod.rs
@@ -286,22 +286,40 @@ fn read_inner(wasi_file: &mut Box<dyn WasiFile>, inner_buffer: &mut [u8]) -> isi
     }
 }
 
+/// The version of WASI. This is determined by the imports namespace
+/// string.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 #[repr(u32)]
 #[allow(non_camel_case_types)]
 pub enum wasi_version_t {
-    Latest = 0,
-    Snapshot0 = 1,
-    Snapshot1 = 2,
-    InvalidVersion = u32::max_value(),
+    /// Latest version.
+    ///
+    /// It's a “floating” version, i.e. it's an alias to the latest
+    /// version (for the moment, `Snapshot1`). Using this version is a
+    /// way to ensure that modules will run only if they come with the
+    /// latest WASI version (in case of security issues for instance),
+    /// by just updating the runtime.
+    ///
+    /// Note that this version is never returned by an API. It is
+    /// provided only by the user.
+    LATEST = 0,
+
+    /// `wasi_unstable`.
+    SNAPSHOT0 = 1,
+
+    /// `wasi_snapshot_preview1`.
+    SNAPSHOT1 = 2,
+
+    /// An invalid version. It matches `u32` maximum value.
+    INVALID_VERSION = 4294967295, // u32::MAX,
 }
 
 impl From<WasiVersion> for wasi_version_t {
     fn from(other: WasiVersion) -> Self {
         match other {
-            WasiVersion::Snapshot0 => wasi_version_t::Snapshot0,
-            WasiVersion::Snapshot1 => wasi_version_t::Snapshot1,
-            WasiVersion::Latest => wasi_version_t::Latest,
+            WasiVersion::Snapshot0 => wasi_version_t::SNAPSHOT0,
+            WasiVersion::Snapshot1 => wasi_version_t::SNAPSHOT1,
+            WasiVersion::Latest => wasi_version_t::LATEST,
         }
     }
 }
@@ -311,10 +329,10 @@ impl TryFrom<wasi_version_t> for WasiVersion {
 
     fn try_from(other: wasi_version_t) -> Result<Self, Self::Error> {
         Ok(match other {
-            wasi_version_t::Snapshot0 => WasiVersion::Snapshot0,
-            wasi_version_t::Snapshot1 => WasiVersion::Snapshot1,
-            wasi_version_t::Latest => WasiVersion::Latest,
-            wasi_version_t::InvalidVersion => return Err("Invalid WASI version cannot be used"),
+            wasi_version_t::SNAPSHOT0 => WasiVersion::Snapshot0,
+            wasi_version_t::SNAPSHOT1 => WasiVersion::Snapshot1,
+            wasi_version_t::LATEST => WasiVersion::Latest,
+            wasi_version_t::INVALID_VERSION => return Err("Invalid WASI version cannot be used"),
         })
     }
 }
@@ -323,7 +341,7 @@ impl TryFrom<wasi_version_t> for WasiVersion {
 pub unsafe extern "C" fn wasi_get_wasi_version(module: &wasm_module_t) -> wasi_version_t {
     get_wasi_version(&module.inner, false)
         .map(Into::into)
-        .unwrap_or(wasi_version_t::InvalidVersion)
+        .unwrap_or(wasi_version_t::INVALID_VERSION)
 }
 
 /// Takes ownership of `wasi_env_t`.

diff --git a/lib/c-api/wasmer_wasm.h b/lib/c-api/wasmer_wasm.h
@@ -62,6 +62,49 @@
 #include <stdlib.h>
 #include "wasm.h"
 
+#if defined(WASMER_WASI_ENABLED)
+/**
+ * The version of WASI. This is determined by the imports namespace
+ * string.
+ */
+enum wasi_version_t {
+#if defined(WASMER_WASI_ENABLED)
+  /**
+   * Latest version.
+   *
+   * It's a “floating” version, i.e. it's an alias to the latest
+   * version (for the moment, `Snapshot1`). Using this version is a
+   * way to ensure that modules will run only if they come with the
+   * latest WASI version (in case of security issues for instance),
+   * by just updating the runtime.
+   *
+   * Note that this version is never returned by an API. It is
+   * provided only by the user.
+   */
+  LATEST = 0,
+#endif
+#if defined(WASMER_WASI_ENABLED)
+  /**
+   * `wasi_unstable`.
+   */
+  SNAPSHOT0 = 1,
+#endif
+#if defined(WASMER_WASI_ENABLED)
+  /**
+   * `wasi_snapshot_preview1`.
+   */
+  SNAPSHOT1 = 2,
+#endif
+#if defined(WASMER_WASI_ENABLED)
+  /**
+   * An invalid version. It matches `u32` maximum value.
+   */
+  INVALID_VERSION = 4294967295,
+#endif
+};
+typedef uint32_t wasi_version_t;
+#endif
+
 #if defined(WASMER_COMPILER_ENABLED)
 /**
  * Kind of compilers that can be used by the engines.
@@ -120,10 +163,6 @@ typedef struct wasi_config_t wasi_config_t;
 typedef struct wasi_env_t wasi_env_t;
 #endif
 
-#if defined(WASMER_WASI_ENABLED)
-typedef struct wasi_version_t wasi_version_t;
-#endif
-
 #if defined(WASMER_WASI_ENABLED)
 void wasi_config_arg(wasi_config_t *config, const char *arg);
 #endif

diff --git a/lib/wasi/src/utils.rs b/lib/wasi/src/utils.rs
@@ -13,6 +13,7 @@ pub fn is_wasi_module(module: &Module) -> bool {
 pub enum WasiVersion {
     /// `wasi_unstable`.
     Snapshot0,
+
     /// `wasi_snapshot_preview1`.
     Snapshot1,