first commit

src/VM/VM.c

@@ -0,0 +1,65 @@
+#include "VM.h"
+#include "../instructions/instructions.h"
+
+void VM_init(VM* vm){
+    memset(vm, 0, sizeof(VM));
+    vm->state = VMState_Initialized;
+}
+
+bool VM_loadProgram(VM* vm, u8* data, size_t size){
+    if(data == NULL){
+        VM_setErrorMessage(vm, "[VM_loadProgram] can't load program because data == NULL");
+        return false;
+    }
+    if(size == 0){
+        VM_setErrorMessage(vm, "[VM_loadProgram] can't load program because size == 0");
+        return false;
+    }
+
+    vm->data = data;
+    vm->data_size = size;
+    return true;
+}
+
+i32 VM_executeProgram(VM* vm){
+    if(vm->data == NULL){
+        VM_setErrorMessage(vm, "[VM_executeProgram] data is null");
+        return -1;
+    }
+
+    size_t pos = 0;
+    while (pos < vm->data_size){
+        u8 opcode = vm->data[pos];
+
+        const Instruction* instr = Instruction_getFromOpcode(opcode);
+        if(instr == NULL){
+            
+            return -1;
+        }
+
+        pos++;
+        i32 bytes_read = instr->implementation(vm, pos);
+        if(bytes_read < 0)
+            return -1;
+
+        pos += bytes_read;
+    }
+
+    if(vm->state != VMState_Exited){
+        VM_setErrorMessage(vm, "[%p] unexpected end of program", (void*)pos);
+        return -1;
+    }
+
+    // exit code of the program should be in ax register
+    return vm->ax.i32v;
+}
+
+bool VM_dataRead(VM* vm, void* dst, size_t pos, size_t size){
+    if(pos + size >= vm->data_size){
+        VM_setErrorMessage(vm, "[%p] unexpected end of data", (void*)vm->data_size);
+        return false;
+    }
+
+    memcpy(dst, vm->data + pos, size);
+    return true;
+}