Data commit

Task/Call-a-function-in-a-shared-library/Wren/call-a-function-in-a-shared-library-1.wren

@@ -0,0 +1,26 @@
+/* call_shared_library_function.wren */
+
+var RTLD_LAZY = 1
+
+foreign class DL {
+    construct open(file, mode) {}
+
+    foreign call(symbol, arg)
+
+    foreign close()
+}
+
+class My {
+    static openimage(s) {
+        System.print("internal openimage opens %(s)...")
+        if (!__handle) __handle = 0
+        __handle = __handle + 1
+        return __handle - 1
+    }
+}
+
+var file = "fake.img"
+var imglib = DL.open("./fakeimglib.so", RTLD_LAZY)
+var imghandle = (imglib != null) ? imglib.call("openimage", file) : My.openimage(file)
+System.print("opened with handle %(imghandle)")
+if (imglib != null) imglib.close()

Task/Call-a-function-in-a-shared-library/Wren/call-a-function-in-a-shared-library-2.wren

@@ -0,0 +1,11 @@
+/*
+    gcc -c -fpic fakeimglib.c
+    gcc -shared fakeimglib.o -o fakeimglib.so
+*/
+#include <stdio.h>
+
+int openimage(const char *s) {
+    static int handle = 100;
+    fprintf(stderr, "opening %s\n", s);
+    return handle++;
+}

Task/Call-a-function-in-a-shared-library/Wren/call-a-function-in-a-shared-library-3.wren

@@ -0,0 +1,116 @@
+/* gcc call_shared_library_function.c -o call_shared_library_function -ldl -lwren -lm */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <dlfcn.h>
+#include "wren.h"
+
+/* C <=> Wren interface functions */
+
+void C_dlAllocate(WrenVM* vm) {
+    const char *file = wrenGetSlotString(vm, 1);
+    int mode = (int)wrenGetSlotDouble(vm, 2);
+    void *imglib = dlopen(file, mode);
+    if (imglib == NULL) wrenSetSlotNull(vm, 0);
+    void** pimglib = (void**)wrenSetSlotNewForeign(vm, 0, 0, sizeof(void*));
+    *pimglib = imglib;
+}
+
+void C_call(WrenVM* vm) {
+    void *imglib = *(void**)wrenGetSlotForeign(vm, 0);
+    const char *symbol = wrenGetSlotString(vm, 1);
+    const char *arg = wrenGetSlotString(vm, 2);
+    int (*extopenimage)(const char *);
+    extopenimage = dlsym(imglib, symbol);
+    int imghandle = extopenimage(arg);
+    wrenSetSlotDouble(vm, 0, (double)imghandle);
+}
+
+void C_close(WrenVM* vm) {
+    void *imglib = *(void**)wrenGetSlotForeign(vm, 0);
+    dlclose(imglib);
+}
+
+WrenForeignClassMethods bindForeignClass(WrenVM* vm, const char* module, const char* className) {
+    WrenForeignClassMethods methods;
+    methods.finalize = NULL;
+    if (strcmp(module, "main") == 0) {
+        if (strcmp(className, "DL") == 0) {
+            methods.allocate = C_dlAllocate;
+        }
+    }
+    return methods;
+}
+
+WrenForeignMethodFn bindForeignMethod(
+    WrenVM* vm,
+    const char* module,
+    const char* className,
+    bool isStatic,
+    const char* signature) {
+    if (strcmp(module, "main") == 0) {
+        if (strcmp(className, "DL") == 0) {
+            if (!isStatic && strcmp(signature, "call(_,_)") == 0) return C_call;
+            if (!isStatic && strcmp(signature, "close()") == 0)   return C_close;
+        }
+    }
+    return NULL;
+}
+
+static void writeFn(WrenVM* vm, const char* text) {
+    printf("%s", text);
+}
+
+void errorFn(WrenVM* vm, WrenErrorType errorType, const char* module, const int line, const char* msg) {
+    switch (errorType) {
+        case WREN_ERROR_COMPILE:
+            printf("[%s line %d] [Error] %s\n", module, line, msg);
+            break;
+        case WREN_ERROR_STACK_TRACE:
+            printf("[%s line %d] in %s\n", module, line, msg);
+            break;
+        case WREN_ERROR_RUNTIME:
+            printf("[Runtime Error] %s\n", msg);
+            break;
+    }
+}
+
+char *readFile(const char *fileName) {
+    FILE *f = fopen(fileName, "r");
+    fseek(f, 0, SEEK_END);
+    long fsize = ftell(f);
+    rewind(f);
+    char *script = malloc(fsize + 1);
+    fread(script, 1, fsize, f);
+    fclose(f);
+    script[fsize] = 0;
+    return script;
+}
+
+int main(int argc, char **argv) {
+    WrenConfiguration config;
+    wrenInitConfiguration(&config);
+    config.writeFn = &writeFn;
+    config.errorFn = &errorFn;
+    config.bindForeignClassFn = &bindForeignClass;
+    config.bindForeignMethodFn = &bindForeignMethod;
+    WrenVM* vm = wrenNewVM(&config);
+    const char* module = "main";
+    const char* fileName = "call_shared_library_function.wren";
+    char *script = readFile(fileName);
+    WrenInterpretResult result = wrenInterpret(vm, module, script);
+    switch (result) {
+        case WREN_RESULT_COMPILE_ERROR:
+            printf("Compile Error!\n");
+            break;
+        case WREN_RESULT_RUNTIME_ERROR:
+            printf("Runtime Error!\n");
+            break;
+        case WREN_RESULT_SUCCESS:
+            break;
+    }
+    wrenFreeVM(vm);
+    free(script);
+    return 0;
+}