jvm.h

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#ifndef JVM_H
#define JVM_H

typedef struct JavaVirtualMachine JavaVirtualMachine;
typedef struct Reference Reference;

#include <stdint.h>
#include "javaclass.h"
#include "opcodes.h"
#include "framestack.h"

enum JVMStatus {
    JVM_STATUS_OK,
    JVM_STATUS_NO_CLASS_LOADED,
    JVM_STATUS_MAIN_CLASS_RESOLUTION_FAILED,
    JVM_STATUS_CLASS_RESOLUTION_FAILED,
    JVM_STATUS_METHOD_RESOLUTION_FAILED,
    JVM_STATUS_FIELD_RESOLUTION_FAILED,
    JVM_STATUS_UNKNOWN_INSTRUCTION,
    JVM_STATUS_OUT_OF_MEMORY,
    JVM_STATUS_MAIN_METHOD_NOT_FOUND,
    JVM_STATUS_INVALID_INSTRUCTION_PARAMETERS
};

typedef struct ClassInstance
{
    JavaClass* c;
    int32_t* data;
} ClassInstance;

typedef struct String
{
    uint8_t* utf8_bytes;
    uint32_t len;
} String;

typedef struct Array
{
    uint32_t length;
    uint8_t* data;
    Opcode_newarray_type type;
} Array;

typedef struct ObjectArray
{
    uint32_t length;
    uint8_t* utf8_className;
    int32_t utf8_len;
    Reference** elements;
} ObjectArray;

typedef enum ReferenceType {
     REFTYPE_ARRAY,
     REFTYPE_CLASSINSTANCE,
     REFTYPE_OBJARRAY,
     REFTYPE_STRING
} ReferenceType;

struct Reference
{
    ReferenceType type;

    union {
        ClassInstance ci;
        Array arr;
        ObjectArray oar;
        String str;
    };
};

typedef struct ReferenceTable
{
    Reference* obj;
    struct ReferenceTable* next;
} ReferenceTable;

typedef struct LoadedClasses
{
    JavaClass* jc;

    uint8_t requiresInit;

    int32_t* staticFieldsData;

    struct LoadedClasses* next;
} LoadedClasses;

struct JavaVirtualMachine
{
    uint8_t status;

    uint8_t simulatingSystemAndStringClasses;

    ReferenceTable* objects;

    FrameStack* frames;

    LoadedClasses* classes;

    char classPath[256];
};

void initJVM(JavaVirtualMachine* jvm);
void deinitJVM(JavaVirtualMachine* jvm);
void executeJVM(JavaVirtualMachine* jvm, LoadedClasses* mainClass);
void setClassPath(JavaVirtualMachine* jvm, const char* path);
uint8_t resolveClass(JavaVirtualMachine* jvm, const uint8_t* className_utf8_bytes, int32_t utf8_len, LoadedClasses** outClass);
uint8_t resolveMethod(JavaVirtualMachine* jvm, JavaClass* jc, cp_info* cp_method, LoadedClasses** outClass);
uint8_t resolveField(JavaVirtualMachine* jvm, JavaClass* jc, cp_info* cp_field, LoadedClasses** outClass);
uint8_t runMethod(JavaVirtualMachine* jvm, JavaClass* jc, method_info* method, uint8_t numberOfParameters);
uint8_t getMethodDescriptorParameterCount(const uint8_t* descriptor_utf8, int32_t utf8_len);

LoadedClasses* addClassToLoadedClasses(JavaVirtualMachine* jvm, JavaClass* jc);
LoadedClasses* isClassLoaded(JavaVirtualMachine* jvm, const uint8_t* utf8_bytes, int32_t utf8_len);
JavaClass* getSuperClass(JavaVirtualMachine* jvm, JavaClass* jc);
uint8_t isClassSuperOf(JavaVirtualMachine* jvm, JavaClass* super, JavaClass* jc);
uint8_t initClass(JavaVirtualMachine* jvm, LoadedClasses* lc);

Reference* newString(JavaVirtualMachine* jvm, const uint8_t* str, int32_t strlen);
Reference* newClassInstance(JavaVirtualMachine* jvm, LoadedClasses* jc);
Reference* newArray(JavaVirtualMachine* jvm, uint32_t length, Opcode_newarray_type type);
Reference* newObjectArray(JavaVirtualMachine* jvm, uint32_t length, const uint8_t* utf8_className, int32_t utf8_len);
Reference* newObjectMultiArray(JavaVirtualMachine* jvm, int32_t* dimensions, uint8_t dimensionsSize,
                               const uint8_t* utf8_className, int32_t utf8_len);

void deleteReference(Reference* obj);

 #define DEBUG_REPORT_INSTRUCTION_ERROR \
    printf("\nAbortion request by instruction at %s:%u.\n", __FILE__, __LINE__); \
    printf("Check at the source file what the cause could be.\n"); \
    printf("It could be an exception that was supposed to be thrown or an unsupported feature.\n"); \
    printf("Execution will proceed, but others instruction will surely request abortion.\n\n");

#endif // JVM_H