initial version of meshless strings, still wrong handling of malloc/free

crates/cpp/helper-types/wit-guest.h

@@ -45,6 +45,10 @@ class string {
   std::string to_string() const {
     return std::string((const char *)data_, length);
   }
+  static string from_view(std::string_view v) {
+    char* addr = (char*)malloc(v.size());
+    return string(addr, v.size());
+  }
 };
 
 /// A vector in linear memory, freed unconditionally using free

crates/cpp/tests/meshless_strings/Makefile

@@ -0,0 +1 @@
+../meshless_resources/Makefile

crates/cpp/tests/meshless_strings/component_a/Makefile

@@ -0,0 +1,12 @@
+CXXFLAGS=-g -O0 -I../../../helper-types
+
+all: component_a
+
+component_a: the_world.cpp main.cpp
+	$(CXX) $(CXXFLAGS) -o $@ $^ -L../component_b -lcomponent_b
+
+bindgen:
+	../../../../../target/debug/wit-bindgen cpp ../wit -w a --wasm64 --format
+
+clean:
+	-rm *~ component_a *.o

crates/cpp/tests/meshless_strings/component_a/main.cpp

@@ -0,0 +1,30 @@
+
+#include "the_world_cpp.h"
+#include <iostream>
+
+void comp_a::exports::foo::foo::strings::A(wit::string &&x) {
+    std::cout << x.get_view() << std::endl;
+}
+wit::string comp_a::exports::foo::foo::strings::B() {
+    wit::string b = wit::string::from_view(std::string_view("hello B"));
+    return b;
+}
+wit::string comp_a::exports::foo::foo::strings::C(wit::string &&a, wit::string &&b) {
+    std::cout << a.get_view() << '|' << b.get_view() << std::endl;
+    wit::string c = wit::string::from_view(std::string_view("hello C"));
+    return c;
+}
+
+int main() {
+    comp_a::foo::foo::strings::A(std::string_view("hello A"));
+
+    {
+        auto b = comp_a::foo::foo::strings::B();
+        std::cout << b.get_view() << std::endl;
+        // make sure that b's result is destructed before calling C
+    }
+
+    auto c = comp_a::foo::foo::strings::C(std::string_view("hello C1"), std::string_view("hello C2"));
+    std::cout << c.get_view() << std::endl;
+    return 0;
+}

crates/cpp/tests/meshless_strings/component_a/the_world.cpp

@@ -0,0 +1,123 @@
+// Generated by `wit-bindgen` 0.3.0. DO NOT EDIT!
+
+// Ensure that the *_component_type.o object is linked in
+#ifdef __wasm32__
+extern void __component_type_object_force_link_the_world(void);
+void __component_type_object_force_link_the_world_public_use_in_this_compilation_unit(
+    void) {
+  __component_type_object_force_link_the_world();
+}
+#endif
+#include "the_world_cpp.h"
+#include <cstdlib> // realloc
+
+extern "C" void *cabi_realloc(void *ptr, size_t old_size, size_t align,
+                              size_t new_size);
+
+__attribute__((__weak__, __export_name__("cabi_realloc"))) void *
+cabi_realloc(void *ptr, size_t old_size, size_t align, size_t new_size) {
+  (void)old_size;
+  if (new_size == 0)
+    return (void *)align;
+  void *ret = realloc(ptr, new_size);
+  if (!ret)
+    abort();
+  return ret;
+}
+
+extern "C" __attribute__((import_module("foo:foo/strings")))
+__attribute__((import_name("a"))) void
+fooX3AfooX2FstringsX00a(uint8_t *, size_t);
+extern "C" __attribute__((import_module("foo:foo/strings")))
+__attribute__((import_name("b"))) void
+fooX3AfooX2FstringsX00b(uint8_t *);
+extern "C" __attribute__((import_module("foo:foo/strings")))
+__attribute__((import_name("c"))) void
+fooX3AfooX2FstringsX00c(uint8_t *, size_t, uint8_t *, size_t, uint8_t *);
+void comp_a::foo::foo::strings::A(std::string_view x) {
+  auto const &vec0 = x;
+  auto ptr0 = (uint8_t *)(vec0.data());
+  auto len0 = (size_t)(vec0.size());
+  fooX3AfooX2FstringsX00a(ptr0, len0);
+}
+wit::string comp_a::foo::foo::strings::B() {
+  size_t ret_area[2];
+  uint8_t *ptr0 = (uint8_t *)(&ret_area);
+  fooX3AfooX2FstringsX00b(ptr0);
+  auto len1 = *((size_t *)(ptr0 + sizeof(size_t)));
+
+  return wit::string((char const *)(*((uint8_t **)(ptr0 + 0))), len1);
+}
+wit::string comp_a::foo::foo::strings::C(std::string_view a, std::string_view b) {
+  auto const &vec0 = a;
+  auto ptr0 = (uint8_t *)(vec0.data());
+  auto len0 = (size_t)(vec0.size());
+  auto const &vec1 = b;
+  auto ptr1 = (uint8_t *)(vec1.data());
+  auto len1 = (size_t)(vec1.size());
+  size_t ret_area[2];
+  uint8_t *ptr2 = (uint8_t *)(&ret_area);
+  fooX3AfooX2FstringsX00c(ptr0, len0, ptr1, len1, ptr2);
+  auto len3 = *((size_t *)(ptr2 + sizeof(size_t)));
+
+  return wit::string((char const *)(*((uint8_t **)(ptr2 + 0))), len3);
+}
+extern "C" __attribute__((__export_name__("foo:foo/strings#a"))) void
+a_fooX3AfooX2FstringsX00a(uint8_t *arg0, size_t arg1) {
+  auto len0 = arg1;
+
+  exports::foo::foo::strings::A(wit::string((char const *)(arg0), len0));
+}
+extern "C" __attribute__((__export_name__("foo:foo/strings#b"))) uint8_t *
+a_fooX3AfooX2FstringsX00b() {
+  auto result0 = exports::foo::foo::strings::B();
+  static size_t ret_area[2];
+  uint8_t *ptr1 = (uint8_t *)(&ret_area);
+  auto const &vec2 = result0;
+  auto ptr2 = (uint8_t *)(vec2.data());
+  auto len2 = (size_t)(vec2.size());
+  result0.leak();
+
+  *((size_t *)(ptr1 + sizeof(size_t))) = len2;
+  *((uint8_t **)(ptr1 + 0)) = ptr2;
+  return ptr1;
+}
+extern "C"
+    __attribute__((__weak__,
+                   __export_name__("cabi_post_fooX3AfooX2FstringsX23b"))) void
+    a_cabi_post_fooX3AfooX2FstringsX00b(uint8_t *arg0) {
+  if ((*((size_t *)(arg0 + sizeof(size_t)))) > 0) {
+    wit::string::drop_raw((void *)(*((uint8_t **)(arg0 + 0))));
+  }
+}
+extern "C" __attribute__((__export_name__("foo:foo/strings#c"))) uint8_t *
+a_fooX3AfooX2FstringsX00c(uint8_t *arg0, size_t arg1, uint8_t *arg2,
+                        size_t arg3) {
+  auto len0 = arg1;
+
+  auto len1 = arg3;
+
+  auto result2 =
+      exports::foo::foo::strings::C(wit::string((char const *)(arg0), len0),
+                                    wit::string((char const *)(arg2), len1));
+  static size_t ret_area[2];
+  uint8_t *ptr3 = (uint8_t *)(&ret_area);
+  auto const &vec4 = result2;
+  auto ptr4 = (uint8_t *)(vec4.data());
+  auto len4 = (size_t)(vec4.size());
+  result2.leak();
+
+  *((size_t *)(ptr3 + sizeof(size_t))) = len4;
+  *((uint8_t **)(ptr3 + 0)) = ptr4;
+  return ptr3;
+}
+extern "C"
+    __attribute__((__weak__,
+                   __export_name__("cabi_post_fooX3AfooX2FstringsX23c"))) void
+    a_cabi_post_fooX3AfooX2FstringsX00c(uint8_t *arg0) {
+  if ((*((size_t *)(arg0 + sizeof(size_t)))) > 0) {
+    wit::string::drop_raw((void *)(*((uint8_t **)(arg0 + 0))));
+  }
+}
+
+// Component Adapters

crates/cpp/tests/meshless_strings/component_a/the_world_cpp.h

@@ -0,0 +1,33 @@
+// Generated by `wit-bindgen` 0.3.0. DO NOT EDIT!
+#ifndef __CPP_GUEST_BINDINGS_THE_WORLD_H
+#define __CPP_GUEST_BINDINGS_THE_WORLD_H
+#include <cstdint>
+#include <string_view>
+#include <utility>
+#include <wit-guest.h>
+namespace comp_a {
+namespace foo {
+namespace foo {
+namespace strings {
+void A(std::string_view x);
+wit::string B();
+wit::string C(std::string_view a, std::string_view b);
+// export_interface Interface(Id { idx: 0 })
+} // namespace strings
+} // namespace foo
+} // namespace foo
+namespace exports {
+namespace foo {
+namespace foo {
+namespace strings {
+void A(wit::string &&x);
+wit::string B();
+wit::string C(wit::string &&a, wit::string &&b);
+} // namespace strings
+} // namespace foo
+} // namespace foo
+} // namespace exports
+}
+using namespace comp_a;
+//using namespace A::foo;
+#endif

crates/cpp/tests/meshless_strings/component_b/Makefile

@@ -0,0 +1,12 @@
+CXXFLAGS=-g -O0 -I../../../helper-types
+
+all: libcomponent_b.a
+
+libcomponent_b.a: the_world.o guest.o
+	ar rcvs $@ $^
+
+bindgen:
+	../../../../../target/debug/wit-bindgen cpp ../wit -w b --wasm64 --format
+
+clean:
+	-rm *~ *.a *.o

crates/cpp/tests/meshless_strings/component_b/guest.cpp

@@ -0,0 +1 @@
+../../native_strings/guest.cpp

crates/cpp/tests/meshless_strings/component_b/the_world.cpp

@@ -0,0 +1,123 @@
+// Generated by `wit-bindgen` 0.3.0. DO NOT EDIT!
+
+// Ensure that the *_component_type.o object is linked in
+#ifdef __wasm32__
+extern void __component_type_object_force_link_the_world(void);
+void __component_type_object_force_link_the_world_public_use_in_this_compilation_unit(
+    void) {
+  __component_type_object_force_link_the_world();
+}
+#endif
+#include "the_world_cpp.h"
+#include <cstdlib> // realloc
+
+extern "C" void *cabi_realloc(void *ptr, size_t old_size, size_t align,
+                              size_t new_size);
+
+__attribute__((__weak__, __export_name__("cabi_realloc"))) void *
+cabi_realloc(void *ptr, size_t old_size, size_t align, size_t new_size) {
+  (void)old_size;
+  if (new_size == 0)
+    return (void *)align;
+  void *ret = realloc(ptr, new_size);
+  if (!ret)
+    abort();
+  return ret;
+}
+
+extern "C" __attribute__((import_module("foo:foo/strings")))
+__attribute__((import_name("a"))) void
+a_fooX3AfooX2FstringsX00a(uint8_t *, size_t);
+extern "C" __attribute__((import_module("foo:foo/strings")))
+__attribute__((import_name("b"))) void
+a_fooX3AfooX2FstringsX00b(uint8_t *);
+extern "C" __attribute__((import_module("foo:foo/strings")))
+__attribute__((import_name("c"))) void
+a_fooX3AfooX2FstringsX00c(uint8_t *, size_t, uint8_t *, size_t, uint8_t *);
+void foo::foo::strings::A(std::string_view x) {
+  auto const &vec0 = x;
+  auto ptr0 = (uint8_t *)(vec0.data());
+  auto len0 = (size_t)(vec0.size());
+  a_fooX3AfooX2FstringsX00a(ptr0, len0);
+}
+wit::string foo::foo::strings::B() {
+  size_t ret_area[2];
+  uint8_t *ptr0 = (uint8_t *)(&ret_area);
+  a_fooX3AfooX2FstringsX00b(ptr0);
+  auto len1 = *((size_t *)(ptr0 + sizeof(size_t)));
+
+  return wit::string((char const *)(*((uint8_t **)(ptr0 + 0))), len1);
+}
+wit::string foo::foo::strings::C(std::string_view a, std::string_view b) {
+  auto const &vec0 = a;
+  auto ptr0 = (uint8_t *)(vec0.data());
+  auto len0 = (size_t)(vec0.size());
+  auto const &vec1 = b;
+  auto ptr1 = (uint8_t *)(vec1.data());
+  auto len1 = (size_t)(vec1.size());
+  size_t ret_area[2];
+  uint8_t *ptr2 = (uint8_t *)(&ret_area);
+  a_fooX3AfooX2FstringsX00c(ptr0, len0, ptr1, len1, ptr2);
+  auto len3 = *((size_t *)(ptr2 + sizeof(size_t)));
+
+  return wit::string((char const *)(*((uint8_t **)(ptr2 + 0))), len3);
+}
+extern "C" __attribute__((__export_name__("foo:foo/strings#a"))) void
+fooX3AfooX2FstringsX00a(uint8_t *arg0, size_t arg1) {
+  auto len0 = arg1;
+
+  exports::foo::foo::strings::A(wit::string((char const *)(arg0), len0));
+}
+extern "C" __attribute__((__export_name__("foo:foo/strings#b"))) uint8_t *
+fooX3AfooX2FstringsX00b() {
+  auto result0 = exports::foo::foo::strings::B();
+  static size_t ret_area[2];
+  uint8_t *ptr1 = (uint8_t *)(&ret_area);
+  auto const &vec2 = result0;
+  auto ptr2 = (uint8_t *)(vec2.data());
+  auto len2 = (size_t)(vec2.size());
+  result0.leak();
+
+  *((size_t *)(ptr1 + sizeof(size_t))) = len2;
+  *((uint8_t **)(ptr1 + 0)) = ptr2;
+  return ptr1;
+}
+extern "C"
+    __attribute__((__weak__,
+                   __export_name__("cabi_post_fooX3AfooX2FstringsX23b"))) void
+    cabi_post_fooX3AfooX2FstringsX00b(uint8_t *arg0) {
+  if ((*((size_t *)(arg0 + sizeof(size_t)))) > 0) {
+    wit::string::drop_raw((void *)(*((uint8_t **)(arg0 + 0))));
+  }
+}
+extern "C" __attribute__((__export_name__("foo:foo/strings#c"))) uint8_t *
+fooX3AfooX2FstringsX00c(uint8_t *arg0, size_t arg1, uint8_t *arg2,
+                        size_t arg3) {
+  auto len0 = arg1;
+
+  auto len1 = arg3;
+
+  auto result2 =
+      exports::foo::foo::strings::C(wit::string((char const *)(arg0), len0),
+                                    wit::string((char const *)(arg2), len1));
+  static size_t ret_area[2];
+  uint8_t *ptr3 = (uint8_t *)(&ret_area);
+  auto const &vec4 = result2;
+  auto ptr4 = (uint8_t *)(vec4.data());
+  auto len4 = (size_t)(vec4.size());
+  result2.leak();
+
+  *((size_t *)(ptr3 + sizeof(size_t))) = len4;
+  *((uint8_t **)(ptr3 + 0)) = ptr4;
+  return ptr3;
+}
+extern "C"
+    __attribute__((__weak__,
+                   __export_name__("cabi_post_fooX3AfooX2FstringsX23c"))) void
+    cabi_post_fooX3AfooX2FstringsX00c(uint8_t *arg0) {
+  if ((*((size_t *)(arg0 + sizeof(size_t)))) > 0) {
+    wit::string::drop_raw((void *)(*((uint8_t **)(arg0 + 0))));
+  }
+}
+
+// Component Adapters

crates/cpp/tests/meshless_strings/component_b/the_world_cpp.h

@@ -0,0 +1 @@
+../../native_strings/the_world_cpp.h