wip

See https://github.com/bytecodealliance/wasmtime/issues/8799

I will make a 1.4.1 release after this is merged

Makefile

@@ -4,10 +4,12 @@ AEXT=a
 FEATURES?=default
 DEFAULT_FEATURES?=yes
 RUST_TARGET?=
+EXTRA_LIBS=
 
 UNAME := $(shell uname -s)
 ifeq ($(UNAME),Darwin)
 	SOEXT=dylib
+	EXTRA_LIBS=-framework Security
 endif
 
 ifeq ($(DEFAULT_FEATURES),no)
@@ -29,7 +31,8 @@ endif
 build:
 	cargo build --release $(FEATURE_FLAGS) --manifest-path libextism/Cargo.toml $(TARGET_FLAGS)
 	sed -e "s%@CMAKE_INSTALL_PREFIX@%$(DEST)%" libextism/extism.pc.in > libextism/extism.pc
-	sed -e "s%@CMAKE_INSTALL_PREFIX@%$(DEST)%" libextism/extism-static.pc.in > libextism/extism-static.pc
+	sed -e "s%@CMAKE_INSTALL_PREFIX@%$(DEST)%" \
+	    -e "s%Libs: %Libs: $(EXTRA_LIBS) %" libextism/extism-static.pc.in > libextism/extism-static.pc
 
 bench:
 	@(cargo criterion $(TARGET_FLAGS) || echo 'For nicer output use cargo-criterion: `cargo install cargo-criterion` - using `cargo bench`') && cargo bench $(TARGET_FLAGS)

README.md

@@ -51,7 +51,7 @@ started:
 | Java SDK    | <img alt="Java SDK" src="https://extism.org/img/sdk-languages/java-android.svg" width="50px"/> | https://github.com/extism/java-sdk                                      | [Sonatype](https://central.sonatype.com/artifact/org.extism.sdk/extism) |
 | .NET SDK    | <img alt=".NET SDK" src="https://extism.org/img/sdk-languages/dotnet.svg" width="50px"/>       | https://github.com/extism/dotnet-sdk <br/>(supports C# & F#!)           | [Nuget](https://www.nuget.org/packages/Extism.Sdk)                      |
 | OCaml SDK   | <img alt="OCaml SDK" src="https://extism.org/img/sdk-languages/ocaml.svg" width="50px"/>       | https://github.com/extism/ocaml-sdk                                     | [opam](https://opam.ocaml.org/packages/extism/)                         |
-| Perl SDK    | <img alt="Perl SDK" src="https://extism.org/img/sdk-languages/perl.svg" width="50px"/>         | https://github.com/extism/perl-sdk                                      | N/A                                                                     |
+| Perl SDK    | <img alt="Perl SDK" src="https://extism.org/img/sdk-languages/perl.svg" width="50px"/>         | https://github.com/extism/perl-sdk                                      | [CPAN](https://metacpan.org/pod/Extism)                                 |
 | PHP SDK     | <img alt="PHP SDK" src="https://extism.org/img/sdk-languages/php.svg" width="50px"/>           | https://github.com/extism/php-sdk                                       | [Packagist](https://packagist.org/packages/extism/extism)               |
 | Python SDK  | <img alt="Python SDK" src="https://extism.org/img/sdk-languages/python.svg" width="50px"/>     | https://github.com/extism/python-sdk                                    | [PyPi](https://pypi.org/project/extism/)                                |
 | Ruby SDK    | <img alt="Ruby SDK" src="https://extism.org/img/sdk-languages/ruby.svg" width="50px"/>         | https://github.com/extism/ruby-sdk                                      | [RubyGems](https://rubygems.org/gems/extism)                            |

kernel/.gitignore

@@ -0,0 +1,3 @@
+owi-out
+*.wat
+proofs

kernel/Cargo.toml

@@ -7,6 +7,7 @@ edition = "2021"
 
 [dev-dependencies]
 wasm-bindgen-test = "0.3.39"
+owi = {git = "https://github.com/dylibso/owi-rs"}
 
 [features]
 default = ["bounds-checking"]
@@ -15,4 +16,4 @@ bounds-checking = []
 [workspace]
 members = [
   "."
-]
+]

kernel/build.sh

@@ -1,5 +1,7 @@
 #!/usr/bin/env bash
 
+set -e
+
 export CARGO_FLAGS=""
 
 while getopts d flag

kernel/examples/alloc_length.rs

@@ -0,0 +1,21 @@
+#![no_main]
+#![no_std]
+use extism_runtime_kernel::*;
+use owi::*;
+
+main!({
+    let n = alloc(1024);
+
+    let x = u64();
+    assume(x > 0);
+
+    let m = alloc(x);
+
+    // 1. Length should equal `x` while active
+    assert(length(m) == x);
+
+    // 2. Length should equal `0` after free
+    free(m); // Free the block
+    assert(length(m) == 0);
+    free(n);
+});

kernel/examples/error.rs

@@ -0,0 +1,24 @@
+#![no_main]
+#![no_std]
+use extism_runtime_kernel::*;
+use owi::*;
+
+main!({
+    let x = u64();
+    let n = u64();
+    let m = u64();
+    assume(x > 0);
+    assume(n > 0);
+    assume(m > 0);
+
+    alloc(n);
+    alloc(m);
+    let n = alloc(x);
+    assert(error_get() == 0);
+
+    error_set(n);
+    assert(error_get() == n);
+    alloc(m);
+    error_set(0);
+    assert(error_get() == 0);
+});

kernel/examples/load_store.rs

@@ -0,0 +1,17 @@
+#![no_main]
+#![no_std]
+use extism_runtime_kernel::*;
+use owi::*;
+
+main!({
+    let x = u64();
+    assume(x > 0);
+
+    let m = alloc(x);
+    assert(length(m) == x);
+    for i in 0..x {
+        store_u8(m + i, i as u8);
+        assert(load_u8(m + i) == i as u8);
+    }
+    free(m);
+});

kernel/examples/reuse.rs

@@ -0,0 +1,39 @@
+#![no_main]
+#![no_std]
+use extism_runtime_kernel::*;
+use owi::*;
+
+main!({
+    let x = u64();
+    assume(x > 0);
+
+    let y = u64();
+    assume(y > 0);
+
+    let mut tmp = 0;
+
+    for _ in 0..y {
+        let m = alloc(x);
+        if tmp == 0 {
+            tmp = m;
+        } else {
+            // Check that the existing block is being re-used
+            assert(m == tmp);
+        }
+
+        assert(length(m) == x);
+        free(m); // Free the block
+    }
+
+    let y = u64();
+    assume(y == x + 1);
+    let n = alloc(y);
+    assert(n > tmp);
+
+    let z = u64();
+    assume(z <= x);
+    assume(x - z < 32);
+    assume(z > 0);
+    let p = alloc(z);
+    assert(p == tmp);
+});

kernel/src/bin/extism-runtime.rs

@@ -1,5 +1,5 @@
-#![no_main]
 #![no_std]
+#![no_main]
 
 pub use extism_runtime_kernel::*;
 

kernel/src/lib.rs

@@ -175,7 +175,7 @@ impl MemoryRoot {
         core::ptr::write_bytes(
             self.blocks.as_mut_ptr() as *mut u8,
             MemoryStatus::Unused as u8,
-            self_position as usize,
+            self_position as usize - core::mem::size_of::<MemoryRoot>(),
         );
 
         // Clear extism runtime metadata
@@ -638,4 +638,15 @@ mod test {
 
         assert_eq!(last, 0);
     }
+
+    #[wasm_bindgen_test]
+    fn test_sym() {
+        unsafe {
+            reset();
+            let a = alloc(47);
+            let b = alloc(20);
+            assert_eq!(length(a), 47);
+            assert_eq!(length(b), 20);
+        }
+    }
 }

kernel/verify.sh

@@ -0,0 +1,23 @@
+#!/usr/bin/env bash
+
+set -e
+
+OUT_DIR=./target/wasm32-unknown-unknown/release/examples/
+get_proof() {
+   cp "$OUT_DIR/$1.wasm" "./proofs/$1.wasm"
+}
+
+cargo build --examples --release --target wasm32-unknown-unknown --no-default-features
+
+mkdir -p proofs
+get_proof alloc_length
+get_proof load_store
+get_proof reuse
+get_proof error
+
+for proof in $(ls proofs/*.wasm); do
+  echo "Checking $proof"
+  owi  conc "$proof" $@
+  echo
+  echo "---"
+done

libextism/.clang-format

@@ -0,0 +1,2 @@
+BasedOnStyle: LLVM
+IndentWidth: 2

libextism/API.md

@@ -14,7 +14,9 @@ Create a new plugin.
 - `functions`: is an array of `ExtismFunction*`
 - `n_functions`: is the number of functions
 - `with_wasi`: enables/disables WASI
-- `errmsg`: error message during plugin creation
+- `errmsg`: error message during plugin creation, this should be freed with
+  `extism_plugin_new_error_free`
+
 
 ```c
 ExtismPlugin extism_plugin_new(const uint8_t *wasm,
@@ -24,6 +26,17 @@ ExtismPlugin extism_plugin_new(const uint8_t *wasm,
                                bool with_wasi,
                                char **errmsg);
 ```
+---
+
+### `extism_plugin_new_error_free`
+
+Frees the error message returned when creating a plugin
+
+```c
+void extism_plugin_new_error_free(char *err);
+```
+
+---
 
 ### `extism_plugin_free`
 
@@ -33,6 +46,8 @@ Remove a plugin from the registry and free associated memory.
 void extism_plugin_free(ExtismPlugin *plugin);
 ```
 
+---
+
 ### `extism_plugin_config`
 
 Update plugin config values, this will merge with the existing values.
@@ -43,6 +58,8 @@ bool extism_plugin_config(ExtismPlugin *plugin,
                           ExtismSize json_size);
 ```
 
+---
+
 ### `extism_plugin_function_exists`
 
 Returns true if `func_name` exists.
@@ -52,6 +69,8 @@ bool extism_plugin_function_exists(ExtismPlugin *plugin,
                                    const char *func_name);
 ```
 
+---
+
 ### `extism_plugin_call`
 
 Call a function.
@@ -59,6 +78,8 @@ Call a function.
 - `data`: is the input data
 - `data_len`: is the length of `data`
 
+Returns `0` when the call is successful.
+
 ```c
 int32_t extism_plugin_call(ExtismPlugin *plugin,
                            const char *func_name,
@@ -66,6 +87,28 @@ int32_t extism_plugin_call(ExtismPlugin *plugin,
                            ExtismSize data_len);
 ```
 
+---
+
+### `extism_plugin_call_with_host_context`
+
+Call a function with additional host context that can be accessed from inside host functions.
+- `func_name`: is the function to call
+- `data`: is the input data
+- `data_len`: is the length of `data`
+- `host_ctx`: an opaque pointer that can be accessed in host functions
+
+Returns `0` when the call is successful.
+
+```c
+int32_t extism_plugin_call_with_host_context(ExtismPlugin *plugin,
+                           const char *func_name,
+                           const uint8_t *data,
+                           ExtismSize data_len,
+                           void *host_ctx);
+```
+
+---
+
 ### `extism_plugin_error`
 
 Get the error associated with a `Plugin`
@@ -74,6 +117,8 @@ Get the error associated with a `Plugin`
 const char *extism_plugin_error(ExtismPlugin *plugin);
 ```
 
+---
+
 ### `extism_plugin_output_length`
 
 Get the length of a plugin's output data.
@@ -82,6 +127,8 @@ Get the length of a plugin's output data.
 ExtismSize extism_plugin_output_length(ExtismPlugin *plugin);
 ```
 
+---
+
 ### `extism_plugin_output_data`
 
 Get the plugin's output data.
@@ -90,6 +137,8 @@ Get the plugin's output data.
 const uint8_t *extism_plugin_output_data(ExtismPlugin *plugin);
 ```
 
+---
+
 ### `extism_plugin_reset`
 
 Reset the Extism runtime, this will invalidate all allocated memory.
@@ -98,6 +147,8 @@ Reset the Extism runtime, this will invalidate all allocated memory.
 bool extism_plugin_reset(ExtismPlugin *plugin);
 ```
 
+---
+
 ### `extism_log_file`
 
 Set log file and level.
@@ -106,6 +157,8 @@ Set log file and level.
 bool extism_log_file(const char *filename, const char *log_level);
 ```
 
+---
+
 ### `extism_log_custom`
 
 Enable a custom log handler, this will buffer logs until `extism_log_drain`
@@ -115,6 +168,8 @@ is called Log level should be one of: info, error, trace, debug, warn
 bool extism_log_custom(const char *log_level);
 ```
 
+---
+
 ### `extism_log_drain`
 
 Calls the provided callback function for each buffered log line.
@@ -124,6 +179,8 @@ This is only needed when `extism_log_custom` is used.
 void extism_log_drain(void (*handler)(const char *, uintptr_t));
 ```
 
+---
+
 ### `extism_version`
 
 Get the Extism version string.
@@ -132,6 +189,8 @@ Get the Extism version string.
 const char *extism_version(void);
 ```
 
+---
+
 ### `extism_current_plugin_memory`
 
 Returns a pointer to the memory of the currently running plugin
@@ -140,6 +199,19 @@ Returns a pointer to the memory of the currently running plugin
 uint8_t *extism_current_plugin_memory(ExtismCurrentPlugin *plugin);
 ```
 
+---
+
+### `extism_current_plugin_host_context`
+
+Get access to the host context, passed in using `extism_plugin_call_with_host_context`
+
+```c
+void *extism_current_plugin_host_context(ExtismCurrentPlugin *plugin);
+```
+
+---
+
+
 ### `extism_current_plugin_memory_alloc`
 
 Allocate a memory block in the currently running plugin
@@ -148,6 +220,8 @@ Allocate a memory block in the currently running plugin
 uint64_t extism_current_plugin_memory_alloc(ExtismCurrentPlugin *plugin, ExtismSize n);
 ```
 
+---
+
 ### `extism_current_plugin_memory_length`
 
 Get the length of an allocated block
@@ -156,6 +230,8 @@ Get the length of an allocated block
 ExtismSize extism_current_plugin_memory_length(ExtismCurrentPlugin *plugin, ExtismSize n);
 ```
 
+---
+
 ### `extism_current_plugin_memory_free`
 
 Free an allocated memory block
@@ -164,6 +240,8 @@ Free an allocated memory block
 void extism_current_plugin_memory_free(ExtismCurrentPlugin *plugin, uint64_t ptr);
 ```
 
+---
+
 ### `extism_function_new`
 Create a new host function
 - `name`: function name, this should be valid UTF-8
@@ -190,6 +268,8 @@ ExtismFunction *extism_function_new(const char *name,
                                     void (*free_user_data)(void *_));
 ```
 
+---
+
 ### `extism_function_set_namespace`
 
 Set the namespace of an `ExtismFunction`
@@ -198,6 +278,8 @@ Set the namespace of an `ExtismFunction`
 void extism_function_set_namespace(ExtismFunction *ptr, const char *namespace_);
 ```
 
+---
+
 ### `extism_function_free`
 
 Free an `ExtismFunction`
@@ -206,6 +288,8 @@ Free an `ExtismFunction`
 void extism_function_free(ExtismFunction *ptr);
 ```
 
+---
+
 ### `extism_plugin_cancel_handle`
 
 Get handle for plugin cancellation
@@ -214,6 +298,8 @@ Get handle for plugin cancellation
 const ExtismCancelHandle *extism_plugin_cancel_handle(const ExtismPlugin *plugin);
 ```
 
+---
+
 ### `extism_plugin_cancel`
 
 Cancel a running plugin from another thread
@@ -222,12 +308,14 @@ Cancel a running plugin from another thread
 bool extism_plugin_cancel(const ExtismCancelHandle *handle);
 ```
 
+---
+
 ## Type definitions:
 
 ### `ExtismPlugin`
 
 ```c
-typedef int32_t ExtismPlugin;
+typedef struct ExtismPlugin ExtismPlugin;
 ```
 
 ### `ExtismSize`
@@ -259,3 +347,5 @@ typedef struct ExtismCurrentPlugin ExtismCurrentPlugin;
 ```c
 typedef struct ExtismCancelHandle ExtismCancelHandle;
 ```
+
+

libextism/Makefile

@@ -4,7 +4,7 @@ build:
 
 .PHONY: static
 static:
-	$(CC) -g -o example example.c -l:libextism.a -lm
+	$(CC) -g -o example example.c -l:libextism.a -lm -lpthread
 
 # if needed, set PKG_CONFIG_PATH= to the directory with extism*.pc installed
 LDFLAGS=`pkg-config --libs extism`

libextism/README.md

@@ -56,7 +56,6 @@ Since you may not have an Extism plug-in on hand to test, let's load a demo plug
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
 
 void print_plugin_output(ExtismPlugin *plugin, int32_t rc){
   if (rc != EXTISM_SUCCESS) {
@@ -64,9 +63,9 @@ void print_plugin_output(ExtismPlugin *plugin, int32_t rc){
     return;
   }
 
-  size_t outlen = extism_plugin_output_length(plugin);
+  ExtismSize outlen = extism_plugin_output_length(plugin);
   const uint8_t *out = extism_plugin_output_data(plugin);
-  write(STDOUT_FILENO, out, outlen);
+  fwrite(out, 1, outlen, stdout);
 }
 
 int main(void) {
@@ -106,9 +105,9 @@ if (rc != EXTISM_SUCCESS) {
   exit(2);
 }
 
-size_t outlen = extism_plugin_output_length(plugin);
+ExtismSize outlen = extism_plugin_output_length(plugin);
 const uint8_t *out = extism_plugin_output_data(plugin);
-write(STDOUT_FILENO, out, outlen);
+fwrite(out, 1, outlen, stdout);
 ```
 
 Will print
@@ -171,7 +170,6 @@ We want to expose two functions to our plugin, `kv_write(key: String, value: Byt
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
 
 // A stubbed out KV store
 typedef struct KVStore KVStore;
@@ -184,14 +182,14 @@ extern const uint32_t fake_kv_store_get(KVStore *kv, const char *key,
 
 // Our host functions to access the fake KV store
 void kv_get(ExtismCurrentPlugin *plugin, const ExtismVal *inputs,
-            size_t ninputs, ExtismVal *outputs, size_t noutputs,
+            ExtismSize ninputs, ExtismVal *outputs, ExtismSize noutputs,
             void *userdata) {
   // Cast the userdata pointer
   KVStore *kv = (KVStore *)userdata;
 
   // Get the offset to the key in the plugin memory
   uint64_t offs = inputs[0].v.i64;
-  size_t keylen = extism_current_plugin_memory_length(plugin, offs);
+  ExtismSize keylen = extism_current_plugin_memory_length(plugin, offs);
 
   // Allocate a new block to return
   uint64_t outoffs =
@@ -205,23 +203,23 @@ void kv_get(ExtismCurrentPlugin *plugin, const ExtismVal *inputs,
   *(uint64_t *)(extism_current_plugin_memory(plugin) + outoffs) = value;
 
   // Return the offset to our allocated block
-  outputs[0].t = PTR;
+  outputs[0].t = EXTISM_PTR;
   outputs[0].v.i64 = outoffs;
 }
 
 void kv_set(ExtismCurrentPlugin *plugin, const ExtismVal *inputs,
-            size_t ninputs, ExtismVal *outputs, size_t noutputs,
+            ExtismSize ninputs, ExtismVal *outputs, ExtismSize noutputs,
             void *userdata) {
   // Cast the userdata pointer
   KVStore *kv = (KVStore *)userdata;
 
   // Get the offset to the key in the plugin memory
   uint64_t keyoffs = inputs[0].v.i64;
-  size_t keylen = extism_current_plugin_memory_length(plugin, keyoffs);
+  ExtismSize keylen = extism_current_plugin_memory_length(plugin, keyoffs);
 
   // Get the offset to the value in the plugin memory
   uint64_t valueoffs = inputs[1].v.i64;
-  size_t valuelen = extism_current_plugin_memory_length(plugin, valueoffs);
+  ExtismSize valuelen = extism_current_plugin_memory_length(plugin, valueoffs);
 
   // Set key => value
   fake_kv_store_set(
@@ -234,13 +232,13 @@ int main(void) {
   const char *manifest = "{\"wasm\": [{\"url\": "
                          "\"https://github.com/extism/plugins/releases/latest/"
                          "download/count_vowels_kvstore.wasm\"}]}";
-  const ExtismValType kv_get_inputs[] = {PTR};
-  const ExtismValType kv_get_outputs[] = {PTR};
+  const ExtismValType kv_get_inputs[] = {EXTISM_PTR};
+  const ExtismValType kv_get_outputs[] = {EXTISM_PTR};
   ExtismFunction *kv_get_fn = extism_function_new(
       "kv_get", kv_get_inputs, 1, kv_get_outputs, 1, kv_get, kv, NULL);
 
-  const ExtismValType kv_set_inputs[] = {PTR};
-  const ExtismValType kv_set_outputs[] = {PTR};
+  const ExtismValType kv_set_inputs[] = {EXTISM_PTR};
+  const ExtismValType kv_set_outputs[] = {EXTISM_PTR};
   ExtismFunction *kv_set_fn = extism_function_new(
       "kv_set", kv_set_inputs, 1, kv_set_outputs, 1, kv_set, kv, NULL);
   const ExtismFunction *functions[] = {kv_get_fn};
@@ -288,5 +286,3 @@ print_plugin_output(plugin, extism_plugin_call(plugin, "count_vowels",
 # => Writing value=6 from key=count-vowels"
 # => {"count": 3, "total": 6, "vowels": "aeiouAEIOU"}
 ```
-
-

libextism/example.c

@@ -9,7 +9,7 @@
 #include <sys/stat.h>
 #include <unistd.h>
 
-void log_handler(const char *line, uintptr_t length) {
+void log_handler(const char *line, ExtismSize length) {
   fwrite(line, length, 1, stderr);
 }
 
@@ -63,8 +63,8 @@ int main(int argc, char *argv[]) {
 
   size_t len = 0;
   uint8_t *data = read_file("../wasm/code-functions.wasm", &len);
-  ExtismValType inputs[] = {PTR};
-  ExtismValType outputs[] = {PTR};
+  ExtismValType inputs[] = {EXTISM_PTR};
+  ExtismValType outputs[] = {EXTISM_PTR};
   ExtismFunction *f =
       extism_function_new("hello_world", inputs, 1, outputs, 1, hello_world,
                           "Hello, again!", free_data);

libextism/extism-static.pc.in

@@ -5,6 +5,6 @@ includedir=${prefix}/include
 Version: 1.0.0
 Name: Extism
 Description: The framework for building with WebAssembly (wasm).
-Libs: -L${libdir} -l:libextism.a
-Libs.private: -lm
+Libs: ${libdir}/libextism.a
+Libs.private: -lm -lpthread
 Cflags: -I${includedir}

libextism/extism.pc.in

@@ -6,5 +6,5 @@ Version: 1.0.0
 Name: Extism
 Description: The framework for building with WebAssembly (wasm).
 Libs: -L${libdir} -lextism
-Libs.private: -lm
+Libs.private: -lm -lpthread
 Cflags: -I${includedir}

manifest/src/lib.rs

@@ -10,7 +10,6 @@ pub type ManifestMemory = MemoryOptions;
 #[serde(deny_unknown_fields)]
 pub struct MemoryOptions {
     /// The max number of WebAssembly pages that should be allocated
-    #[serde(alias = "max")]
     pub max_pages: Option<u32>,
 
     /// The maximum number of bytes allowed in an HTTP response
@@ -62,7 +61,6 @@ pub struct HttpRequest {
 
     /// Request headers
     #[serde(default)]
-    #[serde(alias = "header")]
     pub headers: std::collections::BTreeMap<String, String>,
 
     /// Request method

runtime/Cargo.toml

@@ -9,15 +9,15 @@ repository.workspace = true
 version.workspace = true
 
 [dependencies]
-wasmtime = ">= 14.0.0, < 18.0.0"
-wasmtime-wasi = ">= 14.0.0, < 18.0.0"
+wasmtime = ">= 20.0.0, < 22.0.0"
+wasi-common = ">= 20.0.0, < 22.0.0"
 anyhow = "1"
 serde = {version = "1", features = ["derive"]}
 serde_json = "1"
 toml = "0.8"
 sha2 = "0.10"
 tracing = "0.1"
-tracing-subscriber = {version = "0.3", features = ["std", "env-filter", "fmt"]}
+tracing-subscriber = {version = "0.3.18", features = ["std", "env-filter", "fmt"]}
 url = "2"
 glob = "0.3"
 ureq = {version = "2.5", optional=true}

runtime/src/current_plugin.rs

@@ -194,11 +194,11 @@ impl CurrentPlugin {
             anyhow::bail!("unable to locate an extism kernel global: extism_context",)
         };
 
-        let Val::ExternRef(Some(xs)) = xs.get(store) else {
+        let Val::ExternRef(Some(xs)) = xs.get(&mut store) else {
             anyhow::bail!("expected extism_context to be an externref value",)
         };
 
-        match xs.data().downcast_ref::<T>().cloned() {
+        match xs.data(&mut store)?.downcast_ref::<T>().cloned() {
             Some(xs) => Ok(xs.clone()),
             None => anyhow::bail!("could not downcast extism_context",),
         }
@@ -311,31 +311,29 @@ impl CurrentPlugin {
         id: uuid::Uuid,
     ) -> Result<Self, Error> {
         let wasi = if wasi {
-            let auth = wasmtime_wasi::ambient_authority();
-            let mut ctx = wasmtime_wasi::WasiCtxBuilder::new();
-            for (k, v) in manifest.config.iter() {
-                ctx.env(k, v)?;
-            }
+            let auth = wasi_common::sync::ambient_authority();
+            let random = wasi_common::sync::random_ctx();
+            let clocks = wasi_common::sync::clocks_ctx();
+            let sched = wasi_common::sync::sched_ctx();
+            let table = wasi_common::Table::new();
+            let ctx = wasi_common::WasiCtx::new(random, clocks, sched, table);
 
             if let Some(a) = &manifest.allowed_paths {
                 for (k, v) in a.iter() {
-                    let d = wasmtime_wasi::Dir::open_ambient_dir(k, auth).map_err(|err| {
-                        Error::msg(format!(
-                            "Unable to preopen directory \"{}\": {}",
-                            k.display(),
-                            err.kind()
-                        ))
-                    })?;
-                    ctx.preopened_dir(d, v)?;
+                    let file = Box::new(wasi_common::sync::dir::Dir::from_cap_std(
+                        wasi_common::sync::Dir::open_ambient_dir(k, auth)?,
+                    ));
+                    ctx.push_preopened_dir(file, v)?;
                 }
             }
 
             // Enable WASI output, typically used for debugging purposes
             if std::env::var("EXTISM_ENABLE_WASI_OUTPUT").is_ok() {
-                ctx.inherit_stdout().inherit_stderr();
+                ctx.set_stderr(Box::new(wasi_common::sync::stdio::stderr()));
+                ctx.set_stdout(Box::new(wasi_common::sync::stdio::stdout()));
             }
 
-            Some(Wasi { ctx: ctx.build() })
+            Some(Wasi { ctx })
         } else {
             None
         };

runtime/src/function.rs

@@ -38,8 +38,13 @@ impl From<wasmtime::ValType> for ValType {
             F32 => ValType::F32,
             F64 => ValType::F64,
             V128 => ValType::V128,
-            FuncRef => ValType::FuncRef,
-            ExternRef => ValType::ExternRef,
+            Ref(t) => {
+                if t.heap_type().is_func() {
+                    ValType::FuncRef
+                } else {
+                    ValType::ExternRef
+                }
+            }
         }
     }
 }
@@ -53,8 +58,8 @@ impl From<ValType> for wasmtime::ValType {
             F32 => wasmtime::ValType::F32,
             F64 => wasmtime::ValType::F64,
             V128 => wasmtime::ValType::V128,
-            FuncRef => wasmtime::ValType::FuncRef,
-            ExternRef => wasmtime::ValType::ExternRef,
+            FuncRef => wasmtime::ValType::FUNCREF,
+            ExternRef => wasmtime::ValType::EXTERNREF,
         }
     }
 }
@@ -171,8 +176,8 @@ pub struct Function {
     /// Module name
     pub(crate) namespace: Option<String>,
 
-    /// Function type
-    pub(crate) ty: wasmtime::FuncType,
+    pub(crate) params: Vec<ValType>,
+    pub(crate) results: Vec<ValType>,
 
     /// Function handle
     pub(crate) f: Arc<FunctionInner>,
@@ -185,8 +190,8 @@ impl Function {
     /// Create a new host function
     pub fn new<T: 'static, F>(
         name: impl Into<String>,
-        args: impl IntoIterator<Item = ValType>,
-        returns: impl IntoIterator<Item = ValType>,
+        params: impl IntoIterator<Item = ValType>,
+        results: impl IntoIterator<Item = ValType>,
         user_data: UserData<T>,
         f: F,
     ) -> Function
@@ -198,13 +203,13 @@ impl Function {
     {
         let data = user_data.clone();
         let name = name.into();
-        let args = args.into_iter().map(wasmtime::ValType::from);
-        let returns = returns.into_iter().map(wasmtime::ValType::from);
-        let ty = wasmtime::FuncType::new(args, returns);
-        trace!("Creating function {name}: type={ty:?}");
+        let params = params.into_iter().collect();
+        let results = results.into_iter().collect();
+        trace!("Creating function {name}: params={params:?}, results={results:?}");
         Function {
             name,
-            ty,
+            params,
+            results,
             f: Arc::new(
                 move |mut caller: Caller<_>, inp: &[Val], outp: &mut [Val]| {
                     let x = data.clone();
@@ -219,6 +224,22 @@ impl Function {
         }
     }
 
+    pub(crate) fn ty(&self, engine: &wasmtime::Engine) -> wasmtime::FuncType {
+        wasmtime::FuncType::new(
+            engine,
+            self.params
+                .iter()
+                .cloned()
+                .map(wasmtime::ValType::from)
+                .collect::<Vec<_>>(),
+            self.results
+                .iter()
+                .cloned()
+                .map(wasmtime::ValType::from)
+                .collect::<Vec<_>>(),
+        )
+    }
+
     /// Host function name
     pub fn name(&self) -> &str {
         &self.name
@@ -242,9 +263,14 @@ impl Function {
         self
     }
 
-    /// Get function type
-    pub fn ty(&self) -> &wasmtime::FuncType {
-        &self.ty
+    /// Get param types
+    pub fn params(&self) -> &[ValType] {
+        &self.params
+    }
+
+    /// Get result types
+    pub fn results(&self) -> &[ValType] {
+        &self.results
     }
 }
 

runtime/src/internal.rs

@@ -3,7 +3,7 @@ use crate::*;
 /// WASI context
 pub struct Wasi {
     /// wasi
-    pub ctx: wasmtime_wasi::WasiCtx,
+    pub ctx: wasi_common::WasiCtx,
 }
 
 /// InternalExt provides a unified way of acessing `memory`, `store` and `internal` values

runtime/src/plugin.rs

@@ -212,6 +212,73 @@ fn add_module<T: 'static>(
     Ok(())
 }
 
+fn relink(
+    engine: &Engine,
+    mut store: &mut Store<CurrentPlugin>,
+    imports: &[Function],
+    modules: &BTreeMap<String, Module>,
+    with_wasi: bool,
+) -> Result<(InstancePre<CurrentPlugin>, Linker<CurrentPlugin>), Error> {
+    let mut linker = Linker::new(engine);
+    // Define PDK functions
+    macro_rules! add_funcs {
+            ($($name:ident($($args:expr),*) $(-> $($r:expr),*)?);* $(;)?) => {
+                $(
+                    let t = FuncType::new(&engine, [$($args),*], [$($($r),*)?]);
+                    linker.func_new(EXTISM_ENV_MODULE, stringify!($name), t, pdk::$name)?;
+                )*
+            };
+        }
+
+    // Add builtins
+    use wasmtime::ValType::*;
+    add_funcs!(
+        config_get(I64) -> I64;
+        var_get(I64) -> I64;
+        var_set(I64, I64);
+        http_request(I64, I64) -> I64;
+        http_status_code() -> I32;
+        log_warn(I64);
+        log_info(I64);
+        log_debug(I64);
+        log_error(I64);
+    );
+
+    let mut linked = BTreeSet::new();
+    linker.module(&mut store, EXTISM_ENV_MODULE, &modules[EXTISM_ENV_MODULE])?;
+    linked.insert(EXTISM_ENV_MODULE.to_string());
+
+    // If wasi is enabled then add it to the linker
+    if with_wasi {
+        wasi_common::sync::add_to_linker(&mut linker, |x: &mut CurrentPlugin| {
+            &mut x.wasi.as_mut().unwrap().ctx
+        })?;
+    }
+
+    for f in imports {
+        let name = f.name();
+        let ns = f.namespace().unwrap_or(EXTISM_USER_MODULE);
+        unsafe {
+            linker.func_new(ns, name, f.ty(engine).clone(), &*(f.f.as_ref() as *const _))?;
+        }
+    }
+
+    for (name, module) in modules.iter() {
+        add_module(
+            store,
+            &mut linker,
+            &mut linked,
+            modules,
+            name.clone(),
+            module,
+        )?;
+    }
+
+    let main = &modules[MAIN_KEY];
+    let instance_pre = linker.instantiate_pre(main)?;
+    Ok((instance_pre, linker))
+}
+
 impl Plugin {
     /// Create a new plugin from a Manifest or WebAssembly module, and host functions. The `with_wasi`
     /// parameter determines whether or not the module should be executed with WASI enabled.
@@ -238,7 +305,8 @@ impl Plugin {
             .coredump_on_trap(debug_options.coredump.is_some())
             .profiler(debug_options.profiling_strategy)
             .wasm_tail_call(true)
-            .wasm_function_references(true);
+            .wasm_function_references(true)
+            .wasm_gc(true);
 
         match cache_dir {
             Some(None) => (),
@@ -274,64 +342,9 @@ impl Plugin {
         );
         store.set_epoch_deadline(1);
 
-        let mut linker = Linker::new(&engine);
-        let mut imports: Vec<_> = imports.into_iter().collect();
-        // Define PDK functions
-        macro_rules! add_funcs {
-            ($($name:ident($($args:expr),*) $(-> $($r:expr),*)?);* $(;)?) => {
-                $(
-                    let t = FuncType::new([$($args),*], [$($($r),*)?]);
-                    linker.func_new(EXTISM_ENV_MODULE, stringify!($name), t, pdk::$name)?;
-                )*
-            };
-        }
+        let imports: Vec<Function> = imports.into_iter().collect();
+        let (instance_pre, linker) = relink(&engine, &mut store, &imports, &modules, with_wasi)?;
 
-        // Add builtins
-        use wasmtime::ValType::*;
-        add_funcs!(
-            config_get(I64) -> I64;
-            var_get(I64) -> I64;
-            var_set(I64, I64);
-            http_request(I64, I64) -> I64;
-            http_status_code() -> I32;
-            log_warn(I64);
-            log_info(I64);
-            log_debug(I64);
-            log_error(I64);
-        );
-
-        let mut linked = BTreeSet::new();
-        linker.module(&mut store, EXTISM_ENV_MODULE, &modules[EXTISM_ENV_MODULE])?;
-        linked.insert(EXTISM_ENV_MODULE.to_string());
-
-        // If wasi is enabled then add it to the linker
-        if with_wasi {
-            wasmtime_wasi::add_to_linker(&mut linker, |x: &mut CurrentPlugin| {
-                &mut x.wasi.as_mut().unwrap().ctx
-            })?;
-        }
-
-        for f in &mut imports {
-            let name = f.name();
-            let ns = f.namespace().unwrap_or(EXTISM_USER_MODULE);
-            unsafe {
-                linker.func_new(ns, name, f.ty().clone(), &*(f.f.as_ref() as *const _))?;
-            }
-        }
-
-        for (name, module) in modules.iter() {
-            add_module(
-                &mut store,
-                &mut linker,
-                &mut linked,
-                &modules,
-                name.clone(),
-                module,
-            )?;
-        }
-
-        let main = &modules[MAIN_KEY];
-        let instance_pre = linker.instantiate_pre(main)?;
         let timer_tx = Timer::tx();
         let mut plugin = Plugin {
             modules,
@@ -369,6 +382,7 @@ impl Plugin {
         if self.store_needs_reset {
             let engine = self.store.engine().clone();
             let internal = self.current_plugin_mut();
+            let with_wasi = internal.wasi.is_some();
             self.store = Store::new(
                 &engine,
                 CurrentPlugin::new(
@@ -379,6 +393,16 @@ impl Plugin {
                 )?,
             );
             self.store.set_epoch_deadline(1);
+
+            let (instance_pre, linker) = relink(
+                &engine,
+                &mut self.store,
+                &self._functions,
+                &self.modules,
+                with_wasi,
+            )?;
+            self.linker = linker;
+            self.instance_pre = instance_pre;
             let store = &mut self.store as *mut _;
             let linker = &mut self.linker as *mut _;
             let current_plugin = self.current_plugin_mut();
@@ -389,14 +413,7 @@ impl Plugin {
                     .limiter(|internal| internal.memory_limiter.as_mut().unwrap());
             }
 
-            let main = &self.modules[MAIN_KEY];
-            for (name, module) in self.modules.iter() {
-                if name != MAIN_KEY {
-                    self.linker.module(&mut self.store, name, module)?;
-                }
-            }
             self.instantiations = 0;
-            self.instance_pre = self.linker.instantiate_pre(main)?;
             **instance_lock = None;
             self.store_needs_reset = false;
         }
@@ -449,7 +466,7 @@ impl Plugin {
                 if let Some(f) = x.func() {
                     let (params, mut results) = (f.params(), f.results());
                     match (params.len(), results.len()) {
-                        (0, 1) => results.next() == Some(wasmtime::ValType::I32),
+                        (0, 1) => matches!(results.next(), Some(wasmtime::ValType::I32)),
                         (0, 0) => true,
                         _ => false,
                     }
@@ -465,7 +482,7 @@ impl Plugin {
         &mut self,
         input: *const u8,
         mut len: usize,
-        host_context: Option<ExternRef>,
+        host_context: Option<Rooted<ExternRef>>,
     ) -> Result<(), Error> {
         self.output = Output::default();
         self.clear_error()?;
@@ -599,7 +616,7 @@ impl Plugin {
                     if let Some(reactor_init) = reactor_init {
                         reactor_init.call(&mut store, &[], &mut [])?;
                     }
-                    let mut results = vec![Val::null(); init.ty(&store).results().len()];
+                    let mut results = vec![Val::I32(0); init.ty(&store).results().len()];
                     init.call(
                         &mut store,
                         &[Val::I32(0), Val::I32(0)],
@@ -684,7 +701,7 @@ impl Plugin {
         lock: &mut std::sync::MutexGuard<Option<Instance>>,
         name: impl AsRef<str>,
         input: impl AsRef<[u8]>,
-        host_context: Option<ExternRef>,
+        host_context: Option<Rooted<ExternRef>>,
     ) -> Result<i32, (Error, i32)> {
         let name = name.as_ref();
         let input = input.as_ref();
@@ -732,7 +749,7 @@ impl Plugin {
         self.current_plugin_mut().start_time = std::time::Instant::now();
 
         // Call the function
-        let mut results = vec![wasmtime::Val::null(); n_results];
+        let mut results = vec![wasmtime::Val::I32(0); n_results];
         let mut res = func.call(self.store_mut(), &[], results.as_mut_slice());
 
         // Stop timer
@@ -817,13 +834,7 @@ impl Plugin {
                     }
                 }
 
-                let wasi_exit_code = e
-                    .downcast_ref::<wasmtime_wasi::I32Exit>()
-                    .map(|e| e.0)
-                    .or_else(|| {
-                        e.downcast_ref::<wasmtime_wasi::preview2::I32Exit>()
-                            .map(|e| e.0)
-                    });
+                let wasi_exit_code = e.downcast_ref::<wasi_common::I32Exit>().map(|e| e.0);
                 if let Some(exit_code) = wasi_exit_code {
                     debug!(
                         plugin = self.id.to_string(),
@@ -888,7 +899,13 @@ impl Plugin {
         let data = input.to_bytes()?;
         self.raw_call(&mut lock, name, data, None)
             .map_err(|e| e.0)
-            .and_then(move |_| self.output())
+            .and_then(move |rc| {
+                if rc != 0 {
+                    Err(Error::msg(format!("Returned non-zero exit code: {rc}")))
+                } else {
+                    self.output()
+                }
+            })
     }
 
     pub fn call_with_host_context<'a, 'b, T, U, C>(
@@ -905,7 +922,8 @@ impl Plugin {
         let lock = self.instance.clone();
         let mut lock = lock.lock().unwrap();
         let data = input.to_bytes()?;
-        self.raw_call(&mut lock, name, data, Some(ExternRef::new(host_context)))
+        let ctx = ExternRef::new(&mut self.store, host_context)?;
+        self.raw_call(&mut lock, name, data, Some(ctx))
             .map_err(|e| e.0)
             .and_then(move |_| self.output())
     }

runtime/src/sdk.rs

@@ -41,9 +41,9 @@ pub type ExtismFunctionType = extern "C" fn(
 /// Log drain callback
 pub type ExtismLogDrainFunctionType = extern "C" fn(data: *const std::ffi::c_char, size: Size);
 
-impl From<&wasmtime::Val> for ExtismVal {
-    fn from(value: &wasmtime::Val) -> Self {
-        match value.ty() {
+impl ExtismVal {
+    fn from_val(value: &wasmtime::Val, ctx: impl AsContext) -> Self {
+        match value.ty(ctx) {
             wasmtime::ValType::I32 => ExtismVal {
                 t: ValType::I32,
                 v: ValUnion {
@@ -218,7 +218,11 @@ pub unsafe extern "C" fn extism_function_new(
         output_types.clone(),
         user_data,
         move |plugin, inputs, outputs, user_data| {
-            let inputs: Vec<_> = inputs.iter().map(ExtismVal::from).collect();
+            let store = &*plugin.store;
+            let inputs: Vec<_> = inputs
+                .iter()
+                .map(|x| ExtismVal::from_val(x, store))
+                .collect();
             let mut output_tmp: Vec<_> = output_types
                 .iter()
                 .map(|t| ExtismVal {
@@ -407,20 +411,6 @@ pub unsafe extern "C" fn extism_plugin_config(
             }
         };
 
-    let wasi = &mut plugin.current_plugin_mut().wasi;
-    if let Some(Wasi { ctx, .. }) = wasi {
-        for (k, v) in json.iter() {
-            match v {
-                Some(v) => {
-                    let _ = ctx.push_env(k, v);
-                }
-                None => {
-                    let _ = ctx.push_env(k, "");
-                }
-            }
-        }
-    }
-
     let id = plugin.id;
     let config = &mut plugin.current_plugin_mut().manifest.config;
     for (k, v) in json.into_iter() {
@@ -528,13 +518,11 @@ pub unsafe extern "C" fn extism_plugin_call_with_host_context(
         name
     );
     let input = std::slice::from_raw_parts(data, data_len as usize);
-    let res = plugin.raw_call(
-        &mut lock,
-        name,
-        input,
-        Some(ExternRef::new(CVoidContainer(host_context))),
-    );
-
+    let r = match ExternRef::new(&mut plugin.store, CVoidContainer(host_context)) {
+        Err(e) => return plugin.return_error(&mut lock, e, -1),
+        Ok(x) => x,
+    };
+    let res = plugin.raw_call(&mut lock, name, input, Some(r));
     match res {
         Err((e, rc)) => plugin.return_error(&mut lock, e, rc),
         Ok(x) => x,