Add multimemory example.

Add an example that deals with multiple memories in a single Wasm module.

examples/multimemory.c

@@ -0,0 +1,327 @@
+/*
+An example of how to interact with multiple memories.
+
+You can compile and run this example on Linux with:
+
+   cargo build --release -p wasmtime-c-api
+   cc examples/multimemory.c \
+       -I crates/c-api/include \
+       -I crates/c-api/wasm-c-api/include \
+       target/release/libwasmtime.a \
+       -lpthread -ldl -lm \
+       -o multimemory
+   ./multimemory
+
+Note that on Windows and macOS the command will be similar, but you'll need
+to tweak the `-lpthread` and such annotations.
+*/
+
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <wasm.h>
+#include <wasmtime.h>
+
+static void exit_with_error(const char *message, wasmtime_error_t *error, wasm_trap_t *trap);
+
+void check(bool success) {
+  if (!success) {
+    printf("> Error, expected success\n");
+    exit(1);
+  }
+}
+
+void check_call(wasmtime_context_t *store,
+                wasmtime_func_t *func,
+                const wasmtime_val_t* args,
+                size_t nargs,
+                int32_t expected) {
+  wasmtime_val_t results[1];
+  wasm_trap_t *trap = NULL;
+  wasmtime_error_t *error = wasmtime_func_call(
+      store, func, args, nargs, results, 1, &trap
+  );
+  if (error != NULL || trap != NULL)
+    exit_with_error("failed to call function", error, trap);
+  if (results[0].of.i32 != expected) {
+    printf("> Error on result\n");
+    exit(1);
+  }
+}
+
+void check_call0(wasmtime_context_t *store, wasmtime_func_t *func, int32_t expected) {
+  check_call(store, func, NULL, 0, expected);
+}
+
+void check_call1(wasmtime_context_t *store, wasmtime_func_t *func, int32_t arg, int32_t expected) {
+  wasmtime_val_t args[1];
+  args[0].kind = WASMTIME_I32;
+  args[0].of.i32 = arg;
+  check_call(store, func, args, 1, expected);
+}
+
+void check_call2(wasmtime_context_t *store, wasmtime_func_t *func, int32_t arg1, int32_t arg2, int32_t expected) {
+  wasmtime_val_t args[2];
+  args[0].kind = WASMTIME_I32;
+  args[0].of.i32 = arg1;
+  args[1].kind = WASMTIME_I32;
+  args[1].of.i32 = arg2;
+  check_call(store, func, args, 2, expected);
+}
+
+void check_ok(wasmtime_context_t *store, wasmtime_func_t *func, const wasmtime_val_t* args, size_t nargs) {
+  wasm_trap_t *trap = NULL;
+  wasmtime_error_t *error = wasmtime_func_call(store, func, args, nargs, NULL, 0, &trap);
+  if (error != NULL || trap != NULL)
+    exit_with_error("failed to call function", error, trap);
+}
+
+void check_ok2(wasmtime_context_t *store, wasmtime_func_t *func, int32_t arg1, int32_t arg2) {
+  wasmtime_val_t args[2];
+  args[0].kind = WASMTIME_I32;
+  args[0].of.i32 = arg1;
+  args[1].kind = WASMTIME_I32;
+  args[1].of.i32 = arg2;
+  check_ok(store, func, args, 2);
+}
+
+void check_trap(wasmtime_context_t *store,
+                wasmtime_func_t *func,
+                const wasmtime_val_t *args,
+                size_t nargs,
+                size_t num_results) {
+  assert(num_results <= 1);
+  wasmtime_val_t results[1];
+  wasm_trap_t *trap = NULL;
+  wasmtime_error_t *error = wasmtime_func_call(store, func, args, nargs, results, num_results, &trap);
+  if (error != NULL)
+    exit_with_error("failed to call function", error, NULL);
+  if (trap == NULL) {
+    printf("> Error on result, expected trap\n");
+    exit(1);
+  }
+  wasm_trap_delete(trap);
+}
+
+void check_trap1(wasmtime_context_t *store, wasmtime_func_t *func, int32_t arg) {
+  wasmtime_val_t args[1];
+  args[0].kind = WASMTIME_I32;
+  args[0].of.i32 = arg;
+  check_trap(store, func, args, 1, 1);
+}
+
+void check_trap2(wasmtime_context_t *store, wasmtime_func_t *func, int32_t arg1, int32_t arg2) {
+  wasmtime_val_t args[2];
+  args[0].kind = WASMTIME_I32;
+  args[0].of.i32 = arg1;
+  args[1].kind = WASMTIME_I32;
+  args[1].of.i32 = arg2;
+  check_trap(store, func, args, 2, 0);
+}
+
+int main(int argc, const char* argv[]) {
+  // Initialize.
+  printf("Initializing...\n");
+
+  wasm_config_t *config = wasm_config_new();
+  assert(config != NULL);
+  wasmtime_config_wasm_multi_memory_set(config, true);
+
+  wasm_engine_t *engine = wasm_engine_new_with_config(config);
+  assert(engine != NULL);
+
+  wasmtime_store_t* store = wasmtime_store_new(engine, NULL, NULL);
+  wasmtime_context_t *context = wasmtime_store_context(store);
+
+  // Load our input file to parse it next
+  FILE* file = fopen("examples/multimemory.wat", "r");
+  if (!file) {
+    printf("> Error loading file!\n");
+    return 1;
+  }
+  fseek(file, 0L, SEEK_END);
+  size_t file_size = ftell(file);
+  fseek(file, 0L, SEEK_SET);
+  wasm_byte_vec_t wat;
+  wasm_byte_vec_new_uninitialized(&wat, file_size);
+  if (fread(wat.data, file_size, 1, file) != 1) {
+    printf("> Error loading module!\n");
+    return 1;
+  }
+  fclose(file);
+
+  // Parse the wat into the binary wasm format
+  wasm_byte_vec_t binary;
+  wasmtime_error_t *error = wasmtime_wat2wasm(wat.data, wat.size, &binary);
+  if (error != NULL)
+    exit_with_error("failed to parse wat", error, NULL);
+  wasm_byte_vec_delete(&wat);
+
+  // Compile.
+  printf("Compiling module...\n");
+  wasmtime_module_t* module = NULL;
+  error = wasmtime_module_new(engine, (uint8_t*) binary.data, binary.size, &module);
+  if (error)
+    exit_with_error("failed to compile module", error, NULL);
+  wasm_byte_vec_delete(&binary);
+
+  // Instantiate.
+  printf("Instantiating module...\n");
+  wasmtime_instance_t instance;
+  wasm_trap_t *trap = NULL;
+  error = wasmtime_instance_new(context, module, NULL, 0, &instance, &trap);
+  if (error != NULL || trap != NULL)
+    exit_with_error("failed to instantiate", error, trap);
+  wasmtime_module_delete(module);
+
+  // Extract export.
+  printf("Extracting exports...\n");
+  wasmtime_memory_t memory0, memory1;
+  wasmtime_func_t size0, load0, store0, size1, load1, store1;
+  wasmtime_extern_t item;
+  bool ok;
+  ok = wasmtime_instance_export_get(context, &instance, "memory0", strlen("memory0"), &item);
+  assert(ok && item.kind == WASMTIME_EXTERN_MEMORY);
+  memory0 = item.of.memory;
+  ok = wasmtime_instance_export_get(context, &instance, "size0", strlen("size0"), &item);
+  assert(ok && item.kind == WASMTIME_EXTERN_FUNC);
+  size0 = item.of.func;
+  ok = wasmtime_instance_export_get(context, &instance, "load0", strlen("load0"), &item);
+  assert(ok && item.kind == WASMTIME_EXTERN_FUNC);
+  load0 = item.of.func;
+  ok = wasmtime_instance_export_get(context, &instance, "store0", strlen("store0"), &item);
+  assert(ok && item.kind == WASMTIME_EXTERN_FUNC);
+  store0 = item.of.func;
+  ok = wasmtime_instance_export_get(context, &instance, "memory1", strlen("memory1"), &item);
+  assert(ok && item.kind == WASMTIME_EXTERN_MEMORY);
+  memory1 = item.of.memory;
+  ok = wasmtime_instance_export_get(context, &instance, "size1", strlen("size1"), &item);
+  assert(ok && item.kind == WASMTIME_EXTERN_FUNC);
+  size1 = item.of.func;
+  ok = wasmtime_instance_export_get(context, &instance, "load1", strlen("load1"), &item);
+  assert(ok && item.kind == WASMTIME_EXTERN_FUNC);
+  load1 = item.of.func;
+  ok = wasmtime_instance_export_get(context, &instance, "store1", strlen("store1"), &item);
+  assert(ok && item.kind == WASMTIME_EXTERN_FUNC);
+  store1 = item.of.func;
+
+  // Check initial memory.
+  printf("Checking memory...\n");
+  check(wasmtime_memory_size(context, &memory0) == 2);
+  check(wasmtime_memory_data_size(context, &memory0) == 0x20000);
+  check(wasmtime_memory_data(context, &memory0)[0] == 0);
+  check(wasmtime_memory_data(context, &memory0)[0x1000] == 1);
+  check(wasmtime_memory_data(context, &memory0)[0x1001] == 2);
+  check(wasmtime_memory_data(context, &memory0)[0x1002] == 3);
+  check(wasmtime_memory_data(context, &memory0)[0x1003] == 4);
+
+  check_call0(context, &size0, 2);
+  check_call1(context, &load0, 0, 0);
+  check_call1(context, &load0, 0x1000, 1);
+  check_call1(context, &load0, 0x1001, 2);
+  check_call1(context, &load0, 0x1002, 3);
+  check_call1(context, &load0, 0x1003, 4);
+  check_call1(context, &load0, 0x1ffff, 0);
+  check_trap1(context, &load0, 0x20000);
+
+  check(wasmtime_memory_size(context, &memory1) == 2);
+  check(wasmtime_memory_data_size(context, &memory1) == 0x20000);
+  check(wasmtime_memory_data(context, &memory1)[0] == 0);
+  check(wasmtime_memory_data(context, &memory1)[0x1000] == 4);
+  check(wasmtime_memory_data(context, &memory1)[0x1001] == 3);
+  check(wasmtime_memory_data(context, &memory1)[0x1002] == 2);
+  check(wasmtime_memory_data(context, &memory1)[0x1003] == 1);
+
+  check_call0(context, &size1, 2);
+  check_call1(context, &load1, 0, 0);
+  check_call1(context, &load1, 0x1000, 4);
+  check_call1(context, &load1, 0x1001, 3);
+  check_call1(context, &load1, 0x1002, 2);
+  check_call1(context, &load1, 0x1003, 1);
+  check_call1(context, &load1, 0x1ffff, 0);
+  check_trap1(context, &load1, 0x20000);
+
+  // Mutate memory.
+  printf("Mutating memory...\n");
+  wasmtime_memory_data(context, &memory0)[0x1003] = 5;
+  check_ok2(context, &store0, 0x1002, 6);
+  check_trap2(context, &store0, 0x20000, 0);
+
+  check(wasmtime_memory_data(context, &memory0)[0x1002] == 6);
+  check(wasmtime_memory_data(context, &memory0)[0x1003] == 5);
+  check_call1(context, &load0, 0x1002, 6);
+  check_call1(context, &load0, 0x1003, 5);
+
+  wasmtime_memory_data(context, &memory1)[0x1003] = 7;
+  check_ok2(context, &store1, 0x1002, 8);
+  check_trap2(context, &store1, 0x20000, 0);
+
+  check(wasmtime_memory_data(context, &memory1)[0x1002] == 8);
+  check(wasmtime_memory_data(context, &memory1)[0x1003] == 7);
+  check_call1(context, &load1, 0x1002, 8);
+  check_call1(context, &load1, 0x1003, 7);
+
+  // Grow memory.
+  printf("Growing memory...\n");
+  uint32_t old_size;
+  error = wasmtime_memory_grow(context, &memory0, 1, &old_size);
+  if (error != NULL)
+    exit_with_error("failed to grow memory", error, trap);
+  check(wasmtime_memory_size(context, &memory0) == 3);
+  check(wasmtime_memory_data_size(context, &memory0) == 0x30000);
+
+  check_call1(context, &load0, 0x20000, 0);
+  check_ok2(context, &store0, 0x20000, 0);
+  check_trap1(context, &load0, 0x30000);
+  check_trap2(context, &store0, 0x30000, 0);
+
+  error = wasmtime_memory_grow(context, &memory0, 1, &old_size);
+  assert(error != NULL);
+  wasmtime_error_delete(error);
+  error = wasmtime_memory_grow(context, &memory0, 0, &old_size);
+  if (error != NULL)
+    exit_with_error("failed to grow memory", error, trap);
+
+  error = wasmtime_memory_grow(context, &memory1, 2, &old_size);
+  if (error != NULL)
+    exit_with_error("failed to grow memory", error, trap);
+  check(wasmtime_memory_size(context, &memory1) == 4);
+  check(wasmtime_memory_data_size(context, &memory1) == 0x40000);
+
+  check_call1(context, &load1, 0x30000, 0);
+  check_ok2(context, &store1, 0x30000, 0);
+  check_trap1(context, &load1, 0x40000);
+  check_trap2(context, &store1, 0x40000, 0);
+
+  error = wasmtime_memory_grow(context, &memory1, 1, &old_size);
+  assert(error != NULL);
+  wasmtime_error_delete(error);
+  error = wasmtime_memory_grow(context, &memory1, 0, &old_size);
+  if (error != NULL)
+    exit_with_error("failed to grow memory", error, trap);
+
+  // Shut down.
+  printf("Shutting down...\n");
+  wasmtime_store_delete(store);
+  wasm_engine_delete(engine);
+
+  // All done.
+  printf("Done.\n");
+  return 0;
+}
+
+static void exit_with_error(const char *message, wasmtime_error_t *error, wasm_trap_t *trap) {
+  fprintf(stderr, "error: %s\n", message);
+  wasm_byte_vec_t error_message;
+  if (error != NULL) {
+    wasmtime_error_message(error, &error_message);
+    wasmtime_error_delete(error);
+  } else {
+    wasm_trap_message(trap, &error_message);
+    wasm_trap_delete(trap);
+  }
+  fprintf(stderr, "%.*s\n", (int) error_message.size, error_message.data);
+  wasm_byte_vec_delete(&error_message);
+  exit(1);
+}

examples/multimemory.rs

@@ -0,0 +1,121 @@
+//! An example of how to interact with multiple memories.
+//!
+//! Here a small wasm module with multiple memories is used to show how memory
+//! is initialized, how to read and write memory through the `Memory` object,
+//! and how wasm functions can trap when dealing with out-of-bounds addresses.
+
+// You can execute this example with `cargo run --example example`
+
+use anyhow::Result;
+use wasmtime::*;
+
+fn main() -> Result<()> {
+    // Enable the multi-memory feature.
+    let mut config = Config::new();
+    config.wasm_multi_memory(true);
+
+    let engine = Engine::new(&config)?;
+
+    // Create our `store_fn` context and then compile a module and create an
+    // instance from the compiled module all in one go.
+    let mut store = Store::new(&engine, ());
+    let module = Module::from_file(store.engine(), "examples/multimemory.wat")?;
+    let instance = Instance::new(&mut store, &module, &[])?;
+
+    let memory0 = instance
+        .get_memory(&mut store, "memory0")
+        .ok_or(anyhow::format_err!("failed to find `memory0` export"))?;
+    let size0 = instance.get_typed_func::<(), i32, _>(&mut store, "size0")?;
+    let load0 = instance.get_typed_func::<i32, i32, _>(&mut store, "load0")?;
+    let store0 = instance.get_typed_func::<(i32, i32), (), _>(&mut store, "store0")?;
+
+    let memory1 = instance
+        .get_memory(&mut store, "memory1")
+        .ok_or(anyhow::format_err!("failed to find `memory1` export"))?;
+    let size1 = instance.get_typed_func::<(), i32, _>(&mut store, "size1")?;
+    let load1 = instance.get_typed_func::<i32, i32, _>(&mut store, "load1")?;
+    let store1 = instance.get_typed_func::<(i32, i32), (), _>(&mut store, "store1")?;
+
+    println!("Checking memory...");
+    assert_eq!(memory0.size(&store), 2);
+    assert_eq!(memory0.data_size(&store), 0x20000);
+    assert_eq!(memory0.data_mut(&mut store)[0], 0);
+    assert_eq!(memory0.data_mut(&mut store)[0x1000], 1);
+    assert_eq!(memory0.data_mut(&mut store)[0x1001], 2);
+    assert_eq!(memory0.data_mut(&mut store)[0x1002], 3);
+    assert_eq!(memory0.data_mut(&mut store)[0x1003], 4);
+
+    assert_eq!(size0.call(&mut store, ())?, 2);
+    assert_eq!(load0.call(&mut store, 0)?, 0);
+    assert_eq!(load0.call(&mut store, 0x1000)?, 1);
+    assert_eq!(load0.call(&mut store, 0x1001)?, 2);
+    assert_eq!(load0.call(&mut store, 0x1002)?, 3);
+    assert_eq!(load0.call(&mut store, 0x1003)?, 4);
+    assert_eq!(load0.call(&mut store, 0x1ffff)?, 0);
+    assert!(load0.call(&mut store, 0x20000).is_err()); // out of bounds trap
+
+    assert_eq!(memory1.size(&store), 2);
+    assert_eq!(memory1.data_size(&store), 0x20000);
+    assert_eq!(memory1.data_mut(&mut store)[0], 0);
+    assert_eq!(memory1.data_mut(&mut store)[0x1000], 4);
+    assert_eq!(memory1.data_mut(&mut store)[0x1001], 3);
+    assert_eq!(memory1.data_mut(&mut store)[0x1002], 2);
+    assert_eq!(memory1.data_mut(&mut store)[0x1003], 1);
+
+    assert_eq!(size1.call(&mut store, ())?, 2);
+    assert_eq!(load1.call(&mut store, 0)?, 0);
+    assert_eq!(load1.call(&mut store, 0x1000)?, 4);
+    assert_eq!(load1.call(&mut store, 0x1001)?, 3);
+    assert_eq!(load1.call(&mut store, 0x1002)?, 2);
+    assert_eq!(load1.call(&mut store, 0x1003)?, 1);
+    assert_eq!(load1.call(&mut store, 0x1ffff)?, 0);
+    assert!(load0.call(&mut store, 0x20000).is_err()); // out of bounds trap
+
+    println!("Mutating memory...");
+    memory0.data_mut(&mut store)[0x1003] = 5;
+
+    store0.call(&mut store, (0x1002, 6))?;
+    assert!(store0.call(&mut store, (0x20000, 0)).is_err()); // out of bounds trap
+
+    assert_eq!(memory0.data(&store)[0x1002], 6);
+    assert_eq!(memory0.data(&store)[0x1003], 5);
+    assert_eq!(load0.call(&mut store, 0x1002)?, 6);
+    assert_eq!(load0.call(&mut store, 0x1003)?, 5);
+
+    memory1.data_mut(&mut store)[0x1003] = 7;
+
+    store1.call(&mut store, (0x1002, 8))?;
+    assert!(store1.call(&mut store, (0x20000, 0)).is_err()); // out of bounds trap
+
+    assert_eq!(memory1.data(&store)[0x1002], 8);
+    assert_eq!(memory1.data(&store)[0x1003], 7);
+    assert_eq!(load1.call(&mut store, 0x1002)?, 8);
+    assert_eq!(load1.call(&mut store, 0x1003)?, 7);
+
+    println!("Growing memory...");
+    memory0.grow(&mut store, 1)?;
+    assert_eq!(memory0.size(&store), 3);
+    assert_eq!(memory0.data_size(&store), 0x30000);
+
+    assert_eq!(load0.call(&mut store, 0x20000)?, 0);
+    store0.call(&mut store, (0x20000, 0))?;
+    assert!(load0.call(&mut store, 0x30000).is_err());
+    assert!(store0.call(&mut store, (0x30000, 0)).is_err());
+
+    assert!(memory0.grow(&mut store, 1).is_err());
+    assert!(memory0.grow(&mut store, 0).is_ok());
+
+    memory1.grow(&mut store, 2)?;
+    assert_eq!(memory1.size(&store), 4);
+    assert_eq!(memory1.data_size(&store), 0x40000);
+
+    assert_eq!(load1.call(&mut store, 0x30000)?, 0);
+    store1.call(&mut store, (0x30000, 0))?;
+    assert!(load1.call(&mut store, 0x40000).is_err());
+    assert!(store1.call(&mut store, (0x40000, 0)).is_err());
+
+    assert!(memory1.grow(&mut store, 1).is_err());
+    assert!(memory1.grow(&mut store, 0).is_ok());
+
+    Ok(())
+}

examples/multimemory.wat

@@ -0,0 +1,28 @@
+(module
+  (memory (export "memory0") 2 3)
+  (memory (export "memory1") 2 4)
+
+  (func (export "size0") (result i32) (memory.size 0))
+  (func (export "load0") (param i32) (result i32)
+    local.get 0
+    i32.load8_s (memory 0)
+  )
+  (func (export "store0") (param i32 i32)
+    local.get 0
+    local.get 1
+    i32.store8 (memory 0)
+  )
+  (func (export "size1") (result i32) (memory.size 1))
+  (func (export "load1") (param i32) (result i32)
+    local.get 0
+    i32.load8_s (memory 1)
+  )
+  (func (export "store1") (param i32 i32)
+    local.get 0
+    local.get 1
+    i32.store8 (memory 1)
+  )
+
+  (data (memory 0) (i32.const 0x1000) "\01\02\03\04")
+  (data (memory 1) (i32.const 0x1000) "\04\03\02\01")
+)