Don't #include inside extern "C" blocks.

lib/cli/src/c_gen/object_file_header.rs

@@ -76,7 +76,10 @@ pub fn generate_header_file(
 ) -> String {
     let mut c_statements = vec![];
     c_statements.push(CStatement::LiteralConstant {
-        value: "#include <stdlib.h>\n\n".to_string(),
+        value: "#include <stdlib.h>\n#include <string.h>\n\n".to_string(),
+    });
+    c_statements.push(CStatement::LiteralConstant {
+        value: "#ifdef __cplusplus\nextern \"C\" {\n#endif\n\n".to_string(),
     });
     c_statements.push(CStatement::Declaration {
         name: "module_bytes_len".to_string(),
@@ -285,11 +288,9 @@ pub fn generate_header_file(
         value: HELPER_FUNCTIONS.to_string(),
     });
 
-    let inner_c = generate_c(&c_statements);
+    c_statements.push(CStatement::LiteralConstant {
+        value: "\n#ifdef __cplusplus\n}\n#endif\n\n".to_string(),
+    });
 
-    // we wrap the inner C to work with C++ too
-    format!(
-        "#ifdef __cplusplus\nextern \"C\" {{\n#endif\n\n{}\n\n#ifdef __cplusplus\n}}\n#endif\n",
-        inner_c
-    )
+    generate_c(&c_statements)
 }

lib/cli/src/commands/wasmer_create_exe_main.c

@@ -1,63 +1,42 @@
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 #include "wasmer_wasm.h"
 #include "wasm.h"
 #include "my_wasm.h"
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 
 #define own
 
 // TODO: make this define templated so that the Rust code can toggle it on/off
 #define WASI
 
-#ifdef __cplusplus
-}
-#endif
-
-void print_wasmer_error()
-{
+static void print_wasmer_error() {
   int error_len = wasmer_last_error_length();
   printf("Error len: `%d`\n", error_len);
-  char* error_str = (char*) malloc(error_len);
+  char *error_str = (char *)malloc(error_len);
   wasmer_last_error_message(error_str, error_len);
   printf("%s\n", error_str);
+  free(error_str);
 }
 
 #ifdef WASI
-int find_colon(char* string) {
-  int colon_location = 0;
-  for (int j = 0; j < strlen(string); ++j) {
-    if (string[j] == ':') {
-      colon_location = j;
-      break;
-    }
-  }
-  return colon_location;
-}
-
-void pass_mapdir_arg(wasi_config_t* wasi_config, char* mapdir) {
-  int colon_location = find_colon(mapdir);
+static void pass_mapdir_arg(wasi_config_t *wasi_config, char *mapdir) {
+  int colon_location = strchr(mapdir, ':') - mapdir;
   if (colon_location == 0) {
     // error malformed argument
     fprintf(stderr, "Expected mapdir argument of the form alias:directory\n");
     exit(-1);
   }
+
+  char *alias = (char *)malloc(colon_location + 1);
+  memcpy(alias, mapdir, colon_location);
+  alias[colon_location] = '\0';
+
   int dir_len = strlen(mapdir) - colon_location;
-  char* alias = (char*)malloc(colon_location + 1);
-  char* dir = (char*)malloc(dir_len + 1);
-  int j = 0;
-  for (j = 0; j < colon_location; ++j) {
-    alias[j] = mapdir[j];
-  }
-  alias[j] = 0;
-  for (j = 0; j < dir_len; ++j) {
-    dir[j] = mapdir[j + colon_location + 1];
-  }
-  dir[j] = 0;
+  char *dir = (char *)malloc(dir_len + 1);
+  memcpy(dir, &mapdir[colon_location + 1], dir_len);
+  dir[dir_len] = '\0';
 
   wasi_config_mapdir(wasi_config, alias, dir);
   free(alias);
@@ -66,82 +45,84 @@ void pass_mapdir_arg(wasi_config_t* wasi_config, char* mapdir) {
 
 // We try to parse out `--dir` and `--mapdir` ahead of time and process those
 // specially. All other arguments are passed to the guest program.
-void handle_arguments(wasi_config_t* wasi_config, int argc, char* argv[]) {
+static void handle_arguments(wasi_config_t *wasi_config, int argc,
+                             char *argv[]) {
   for (int i = 1; i < argc; ++i) {
-    // We probably want special args like `--dir` and `--mapdir` to not be passed directly
+    // We probably want special args like `--dir` and `--mapdir` to not be
+    // passed directly
     if (strcmp(argv[i], "--dir") == 0) {
       // next arg is a preopen directory
-      if ((i + 1) < argc ) {
+      if ((i + 1) < argc) {
         i++;
         wasi_config_preopen_dir(wasi_config, argv[i]);
       } else {
-        fprintf(stderr, "--dir expects a following argument specifying which directory to preopen\n");
+        fprintf(stderr, "--dir expects a following argument specifying which "
+                        "directory to preopen\n");
         exit(-1);
       }
-    }
-    else if (strcmp(argv[i], "--mapdir") == 0) {
+    } else if (strcmp(argv[i], "--mapdir") == 0) {
       // next arg is a mapdir
-      if ((i + 1) < argc ) {
+      if ((i + 1) < argc) {
         i++;
         pass_mapdir_arg(wasi_config, argv[i]);
       } else {
-        fprintf(stderr, "--mapdir expects a following argument specifying which directory to preopen in the form alias:directory\n");
+        fprintf(stderr,
+                "--mapdir expects a following argument specifying which "
+                "directory to preopen in the form alias:directory\n");
         exit(-1);
       }
-    }
-    else if (strncmp(argv[i], "--dir=", strlen("--dir=")) == 0 ) {
+    } else if (strncmp(argv[i], "--dir=", strlen("--dir=")) == 0) {
       // this arg is a preopen dir
-      char* dir = argv[i] + strlen("--dir=");
+      char *dir = argv[i] + strlen("--dir=");
       wasi_config_preopen_dir(wasi_config, dir);
-    }
-    else if (strncmp(argv[i], "--mapdir=", strlen("--mapdir=")) == 0 ) {
+    } else if (strncmp(argv[i], "--mapdir=", strlen("--mapdir=")) == 0) {
       // this arg is a mapdir
-      char* mapdir = argv[i] + strlen("--mapdir=");
+      char *mapdir = argv[i] + strlen("--mapdir=");
       pass_mapdir_arg(wasi_config, mapdir);
-    }
-    else {
+    } else {
       // guest argument
       wasi_config_arg(wasi_config, argv[i]);
     }
   }
 }
 #endif
 
-int main(int argc, char* argv[]) {
-  wasm_config_t* config = wasm_config_new();
+int main(int argc, char *argv[]) {
+  wasm_config_t *config = wasm_config_new();
   wasm_config_set_engine(config, OBJECT_FILE);
-  wasm_engine_t* engine = wasm_engine_new_with_config(config);
-  wasm_store_t* store = wasm_store_new(engine);
-  
-  wasm_module_t* module = wasmer_object_file_engine_new(store, argv[0]);
-  if (! module) {
+  wasm_engine_t *engine = wasm_engine_new_with_config(config);
+  wasm_store_t *store = wasm_store_new(engine);
+
+  wasm_module_t *module = wasmer_object_file_engine_new(store, argv[0]);
+  if (!module) {
     fprintf(stderr, "Failed to create module\n");
     print_wasmer_error();
     return -1;
   }
 
-  // We have now finished the memory buffer book keeping and we have a valid Module.
-
-  #ifdef WASI
-  wasi_config_t* wasi_config = wasi_config_new(argv[0]);
+  // We have now finished the memory buffer book keeping and we have a valid
+  // Module.
+
+#ifdef WASI
+  wasi_config_t *wasi_config = wasi_config_new(argv[0]);
   handle_arguments(wasi_config, argc, argv);
 
-  wasi_env_t* wasi_env = wasi_env_new(wasi_config);
+  wasi_env_t *wasi_env = wasi_env_new(wasi_config);
   if (!wasi_env) {
     fprintf(stderr, "Error building WASI env!\n");
     print_wasmer_error();
     return 1;
   }
-  #endif
-  
+#endif
+
   wasm_importtype_vec_t import_types;
   wasm_module_imports(module, &import_types);
 
   wasm_extern_vec_t imports;
   wasm_extern_vec_new_uninitialized(&imports, import_types.size);
   wasm_importtype_vec_delete(&import_types);
-  
-  #ifdef WASI
+
+#ifdef WASI
   bool get_imports_result = wasi_get_imports(store, module, wasi_env, &imports);
   wasi_env_delete(wasi_env);
 
@@ -151,18 +132,18 @@ int main(int argc, char* argv[]) {
 
     return 1;
   }
-  #endif
-  
-  wasm_instance_t* instance = wasm_instance_new(store, module, &imports, NULL);
+#endif
+
+  wasm_instance_t *instance = wasm_instance_new(store, module, &imports, NULL);
 
   if (!instance) {
     fprintf(stderr, "Failed to create instance\n");
     print_wasmer_error();
     return -1;
   }
-  
-  #ifdef WASI
-  own wasm_func_t* start_function = wasi_get_start_function(instance);
+
+#ifdef WASI
+  own wasm_func_t *start_function = wasi_get_start_function(instance);
   if (!start_function) {
     fprintf(stderr, "`_start` function not found\n");
     print_wasmer_error();
@@ -171,15 +152,15 @@ int main(int argc, char* argv[]) {
 
   wasm_val_vec_t args = WASM_EMPTY_VEC;
   wasm_val_vec_t results = WASM_EMPTY_VEC;
-  own wasm_trap_t* trap = wasm_func_call(start_function, &args, &results);
+  own wasm_trap_t *trap = wasm_func_call(start_function, &args, &results);
   if (trap) {
     fprintf(stderr, "Trap is not NULL: TODO:\n");
     return -1;
   }
-  #endif
+#endif
 
   // TODO: handle non-WASI start (maybe with invoke?)
-  
+
   wasm_instance_delete(instance);
   wasm_module_delete(module);
   wasm_store_delete(store);

lib/engine-object-file/README.md

@@ -25,10 +25,6 @@ Target: x86_64-apple-darwin
 Now lets create a program to link with this object file.
 
 ```C
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 #include "wasmer_wasm.h"
 #include "wasm.h"
 #include "my_wasm.h"
@@ -38,17 +34,14 @@ extern "C" {
 
 #define own
 
-#ifdef __cplusplus
-}
-#endif
-
-void print_wasmer_error()
+static void print_wasmer_error()
 {
     int error_len = wasmer_last_error_length();
     printf("Error len: `%d`\n", error_len);
     char* error_str = (char*) malloc(error_len);
     wasmer_last_error_message(error_str, error_len);
     printf("Error str: `%s`\n", error_str);
+    free(error_str);
 }
 
 int main() {
@@ -59,7 +52,7 @@ int main() {
         wasm_store_t* store = wasm_store_new(engine);
 
         wasm_module_t* module = wasmer_object_file_engine_new(store, "qjs.wasm");
-        if (! module) {
+        if (!module) {
                 printf("Failed to create module\n");
                 print_wasmer_error();
                 return -1;