add IT support

Author: mikevoronov

.gitignore

@@ -4,3 +4,6 @@
 # Wasm files
 *.wasm
 *.wat
+
+# REPL history
+.repl_history

Config.toml

@@ -0,0 +1,6 @@
+modules_dir = "./"
+
+[[module]]
+    name = "sqlite3"
+    mem_pages_count = 100
+    logger_enabled = true

Makefile

@@ -7,9 +7,11 @@ LDFLAGS = -Wl,--no-entry,--demangle,--allow-undefined
 EXPORT_FUNCS = \
 	--export=allocate,$\
 	--export=deallocate,$\
-	--export=invoke,$\
-	--export=load,$\
-	--export=store
+	--export=set_result_size,$\
+	--export=set_result_ptr,$\
+	--export=get_result_size,$\
+	--export=get_result_ptr,$\
+	--export=invoke
 SQLITE_SRC = \
 	src/alter.c\
 	src/analyze.c\

sdk/logger.h

@@ -2,7 +2,7 @@
 #define FLUENCE_C_SDK_LOGGER_H
 
 #define __LOGGER_IMPORT(name) \
-    __attribute__((__import_module__("logger"), __import_name__(#name)))
+    __attribute__((__import_module__("host"), __import_name__(#name)))
 
 /**
  * Writes provided utf8 string to Wasm VM logger.

sqlite3.wit

@@ -0,0 +1,44 @@
+;; Fluence SQLite fork Wasm Interface Types
+
+;; allocate
+(@interface type (func (param i32) (result i32)))       ;; 0
+
+;; deallocate
+(@interface type (func (param i32 i32)))                ;; 1
+
+;; invoke
+(@interface type (func (param string) (result string))) ;; 2
+
+;; get_result_ptr/get_result_size
+(@interface type (func (result i32)))                   ;; 3
+
+;; set_result_ptr/set_result_size
+(@interface type (func (param i32)))                    ;; 4
+
+
+(@interface export "allocate" (func  0))               ;; 0
+(@interface export "deallocate" (func 1))              ;; 1
+(@interface export "invoke" (func 2))                  ;; 2
+(@interface export "get_result_size" (func 3))         ;; 3
+(@interface export "get_result_ptr" (func 3))          ;; 4
+(@interface export "set_result_size" (func 4))         ;; 5
+(@interface export "set_result_ptr" (func 4))          ;; 6
+
+;; adapter for export invoke function
+(@interface func (type 2)
+    arg.get 0
+    string.size
+    call-core 0             ;; call allocate
+    arg.get 0
+    string.lower_memory
+    call-core 2             ;; call invoke
+    call-core 4             ;; call get_result_size
+    call-core 3             ;; call get_result_ptr
+    string.lift_memory
+    call-core 4             ;; call get_result_size
+    call-core 3             ;; call get_result_ptr
+    call-core 1             ;; call deallocate
+)
+
+;; Implementations
+(@interface implement (func 2) (func 2))

src/wrapper.c

@@ -3,6 +3,8 @@
 #include "sqliteInt.h"
 
 sqlite3 *state;
+char *RESULT_PTR;
+int RESULT_SIZE;
 
 int init() {
   const int rc = sqlite3_initialize();
@@ -15,14 +17,6 @@ int init() {
 
 int g_isInited = 0;
 
-void store(char *ptr, unsigned char byte) {
-  *ptr = byte;
-}
-
-unsigned char load(const unsigned char *ptr) {
-  return *ptr;
-}
-
 void* allocate(size_t size) {
   return malloc(size + 1);
 }
@@ -31,15 +25,20 @@ void deallocate(void *ptr, int size) {
   free(ptr);
 }
 
-char *write_response(char *response, int response_size) {
-  char *result_response = allocate(response_size + 4);
+void set_result_ptr(char *ptr) {
+  RESULT_PTR = ptr;
+}
 
-  for(int i = 0; i < 4; ++i) {
-    result_response[i] = (response_size >> 8*i) & 0xFF;
-  }
+void set_result_size(int size) {
+  RESULT_SIZE = size;
+}
+
+int get_result_size(void) {
+  return RESULT_SIZE;
+}
 
-  memcpy(result_response + 4, response, response_size);
-  return result_response;
+char *get_result_ptr() {
+  return RESULT_PTR;
 }
 
 typedef struct ShellText ShellText;
@@ -114,7 +113,7 @@ static int captureOutputCallback(void *pArg, int nArg, char **azArg, char **az){
   return 0;
 }
 
-const char *invoke(char *request, int request_size) {
+void invoke(char *request, int request_size) {
   if(g_isInited == 0) {
     // TODO: check the return code
     init();
@@ -141,19 +140,17 @@ const char *invoke(char *request, int request_size) {
 
   char *response = 0;
   if(rc || errorMessage) {
-    response = write_response(errorMessage, strlen(errorMessage));
+    RESULT_PTR = errorMessage;
+    RESULT_SIZE = strlen(errorMessage);
   }
   else {
     if(str.n != 0) {
-      response = write_response(str.z, str.n);
+      RESULT_PTR = str.z;
+      RESULT_SIZE = str.n;
     } else {
       // if a request was successfull, sqlite doesn't return anything as the result string
-      const char success_result[] = "OK";
-      response = write_response((char *)success_result, strlen(success_result));
+      RESULT_PTR = strdup("OK");
+      RESULT_SIZE = 2;
     }
   }
-
-  freeText(&str);
-
-  return response;
 }