/* Jim_Obj related macros */
#define Jim_IncrRefCount(objPtr) \
    ++(objPtr)->refCount
#define Jim_DecrRefCount(interp, objPtr) \
    if (--(objPtr)->refCount <= 0) Jim_FreeObj(interp, objPtr)
#define Jim_IsShared(objPtr) \
    ((objPtr)->refCount > 1)

/* This macro is used when we allocate a new object using
 * Jim_New...Obj(), but for some error we need to destroy it.
 * Instead to use Jim_IncrRefCount() + Jim_DecrRefCount() we
 * can just call Jim_FreeNewObj. To call Jim_Free directly
 * seems too raw, the object handling may change and we want
 * that Jim_FreeNewObj() can be called only against objects
 * that are belived to have refcount == 0. */
#define Jim_FreeNewObj Jim_FreeObj

/* Free the internal representation of the object. */
#define Jim_FreeIntRep(i,o) \
    if ((o)->typePtr && (o)->typePtr->freeIntRepProc) \
        (o)->typePtr->freeIntRepProc(i, o)

/* Get the internal representation pointer */
#define Jim_GetIntRepPtr(o) (o)->internalRep.ptr

/* Set the internal representation pointer */
#define Jim_SetIntRepPtr(o, p) \
    (o)->internalRep.ptr = (p)

/* The object type structure.
 * There are four methods.
 *
 * - FreeIntRep is used to free the internal representation of the object.
 *   Can be NULL if there is nothing to free.
 * - DupIntRep is used to duplicate the internal representation of the object.
 *   If NULL, when an object is duplicated, the internalRep union is
 *   directly copied from an object to another.
 *   Note that it's up to the caller to free the old internal repr of the
 *   object before to call the Dup method.
 * - UpdateString is used to create the string from the internal repr.
 * - setFromAny is used to convert the current object into one of this type.
 */

struct Jim_Interp;

typedef void (Jim_FreeInternalRepProc)(struct Jim_Interp *interp,
        struct Jim_Obj *objPtr);
typedef void (Jim_DupInternalRepProc)(struct Jim_Interp *interp,
        struct Jim_Obj *srcPtr, Jim_Obj *dupPtr);
typedef void (Jim_UpdateStringProc)(struct Jim_Obj *objPtr);
    
typedef struct Jim_ObjType {
    const char *name; /* The name of the type. */
    Jim_FreeInternalRepProc *freeIntRepProc;
    Jim_DupInternalRepProc *dupIntRepProc;
    Jim_UpdateStringProc *updateStringProc;
    int flags;
} Jim_ObjType;

/* Jim_ObjType flags */
#define JIM_TYPE_NONE 0        /* No flags */
#define JIM_TYPE_REFERENCES 1    /* The object may contain referneces. */

/* Starting from 1 << 20 flags are reserved for private uses of
 * different calls. This way the same 'flags' argument may be used
 * to pass both global flags and private flags. */
#define JIM_PRIV_FLAG_SHIFT 20

/* -----------------------------------------------------------------------------
 * Call frame, vars, commands structures
 * ---------------------------------------------------------------------------*/

/* Call frame */
typedef struct Jim_CallFrame {
    unsigned jim_wide id; /* Call Frame ID. Used for caching. */
    struct Jim_HashTable vars; /* Where local vars are stored */
    struct Jim_HashTable *staticVars; /* pointer to procedure static vars */
    struct Jim_CallFrame *parentCallFrame;
    Jim_Obj *const *argv; /* object vector of the current procedure call. */
    int argc; /* number of args of the current procedure call. */
    Jim_Obj *procArgsObjPtr; /* arglist object of the running procedure */
    Jim_Obj *procBodyObjPtr; /* body object of the running procedure */
    struct Jim_CallFrame *nextFramePtr;
} Jim_CallFrame;

/* The var structure. It just holds the pointer of the referenced
 * object. If linkFramePtr is not NULL the variable is a link
 * to a variable of name store on objPtr living on the given callframe
 * (this happens when the [global] or [upvar] command is used).
 * The interp in order to always know how to free the Jim_Obj associated
 * with a given variable because In Jim objects memory managment is
 * bound to interpreters. */
typedef struct Jim_Var {
    Jim_Obj *objPtr;
    struct Jim_CallFrame *linkFramePtr;
} Jim_Var;
    
/* The cmd structure. */
typedef int (*Jim_CmdProc)(struct Jim_Interp *interp, int argc,
    Jim_Obj *const *argv);
typedef void (*Jim_DelCmdProc)(struct Jim_Interp *interp, void *privData);

/* A command is implemented in C if funcPtr is != NULL, otherwise
 * it's a Tcl procedure with the arglist and body represented by the
 * two objects referenced by arglistObjPtr and bodyoObjPtr. */
typedef struct Jim_Cmd {
    Jim_CmdProc cmdProc; /* Not-NULL for a C command. */
    void *privData; /* Only used for C commands. */
    Jim_DelCmdProc delProc; /* Called when the command is deleted if != NULL */
    Jim_Obj *argListObjPtr;
    Jim_Obj *bodyObjPtr;
    Jim_HashTable *staticVars; /* Static vars hash table. NULL if no statics. */
    int arityMin; /* Min number of arguments. */
    int arityMax; /* Max number of arguments. */
} Jim_Cmd;

/* Pseudo Random Number Generator State structure */
typedef struct Jim_PrngState {
    unsigned char sbox[256];
    unsigned int i, j;
} Jim_PrngState;

/* -----------------------------------------------------------------------------
 * Jim interpreter structure.
 * Fields similar to the real Tcl interpreter structure have the same names.
 * ---------------------------------------------------------------------------*/
typedef struct Jim_Interp {
    Jim_Obj *result; /* object returned by the last command called. */
    int errorLine; /* Error line where an error occurred. */
    const char *errorFileName; /* Error file where an error occurred. */
    int numLevels; /* Number of current nested calls. */
    int maxNestingDepth; /* Used for infinite loop detection. */
    int returnCode; /* Completion code to return on JIM_RETURN. */
    int exitCode; /* Code to return to the OS on JIM_EXIT. */
    Jim_CallFrame *framePtr; /* Pointer to the current call frame */
    Jim_CallFrame *topFramePtr; /* toplevel/global frame pointer. */
    struct Jim_HashTable commands; /* Commands hash table */
    unsigned jim_wide procEpoch; /* Incremented every time the result
                of procedures names lookup caching
                may no longer be valid. */
    unsigned jim_wide callFrameEpoch; /* Incremented every time a new
                callframe is created. This id is used for the
                'ID' field contained in the Jim_CallFrame
                structure. */
    Jim_Obj *liveList; /* Linked list of all the live objects. */
    Jim_Obj *freeList; /* Linked list of all the unused objects. */
    const char *scriptFileName; /* File name of the script currently in execution. */
    Jim_Obj *emptyObj; /* Shared empty string object. */
    unsigned jim_wide referenceNextId; /* Next id for reference. */
    struct Jim_HashTable references; /* References hash table. */
    jim_wide lastCollectId; /* reference max Id of the last GC
                execution. It's set to -1 while the collection
                is running as sentinel to avoid to recursive
                calls via the [collect] command inside
                finalizers. */
    time_t lastCollectTime; /* unix time of the last GC execution */
    struct Jim_HashTable sharedStrings; /* Shared Strings hash table */
    Jim_Obj *stackTrace; /* Stack trace object. */
    Jim_Obj *unknown; /* Unknown command cache */
    int errorFlag; /* Set if an error occurred during execution. */
    int evalRetcodeLevel; /* Level where the last return with code JIM_EVAL
                             happened. */
    void *cmdPrivData; /* Used to pass the private data pointer to
                  a command. It is set to what the user specified
                  via Jim_CreateCommand(). */

    struct Jim_HashTable stub; /* Stub hash table to export API */
    /* Jim_GetApi() function pointer, used to bootstrap the STUB table */
    int (*getApiFuncPtr)(struct Jim_Interp *, const char *, void *);
    struct Jim_CallFrame *freeFramesList; /* list of CallFrame structures. */
    struct Jim_HashTable assocData; /* per-interp storage for use by packages */
    Jim_PrngState *prngState; /* per interpreter Random Number Gen. state. */
    struct Jim_HashTable packages; /* Provided packages hash table */
    FILE *stdin; /* input file pointer, 'stdin' by default */
    FILE *stdout; /* output file pointer, 'stdout' by default */
    FILE *stderr; /* errors file pointer, 'stderr' by default */
} Jim_Interp;

/* Currently provided as macro that performs the increment.
 * At some point may be a real function doing more work.
 * The proc epoch is used in order to know when a command lookup
 * cached can no longer considered valid. */
#define Jim_InterpIncrProcEpoch(i) (i)->procEpoch++
#define Jim_SetResultString(i,s,l) Jim_SetResult(i, Jim_NewStringObj(i,s,l))
#define Jim_SetEmptyResult(i) Jim_SetResult(i, (i)->emptyObj)
#define Jim_GetResult(i) ((i)->result)
#define Jim_CmdPrivData(i) ((i)->cmdPrivData)

/* Note that 'o' is expanded only one time inside this macro,
 * so it's safe to use side effects. */
#define Jim_SetResult(i,o) do {     \
    Jim_Obj *_resultObjPtr_ = (o);    \
    Jim_IncrRefCount(_resultObjPtr_); \
    Jim_DecrRefCount(i,(i)->result);  \
    (i)->result = _resultObjPtr_;     \
} while(0)

/* Reference structure. The interpreter pointer is held within privdata member in HashTable */
#define JIM_REFERENCE_TAGLEN 7 /* The tag is fixed-length, because the reference
                                  string representation must be fixed length. */
typedef struct Jim_Reference {
    Jim_Obj *objPtr;
    Jim_Obj *finalizerCmdNamePtr;
    char tag[JIM_REFERENCE_TAGLEN+1];
} Jim_Reference;

/* -----------------------------------------------------------------------------
 * Exported API prototypes.
 * ---------------------------------------------------------------------------*/

/* Macros that are common for extensions and core. */
#define Jim_NewEmptyStringObj(i) Jim_NewStringObj(i, "", 0)

/* The core includes real prototypes, extensions instead
 * include a global function pointer for every function exported.
 * Once the extension calls Jim_InitExtension(), the global
 * functon pointers are set to the value of the STUB table
 * contained in the Jim_Interp structure.
 *
 * This makes Jim able to load extensions even if it is statically
 * linked itself, and to load extensions compiled with different
 * versions of Jim (as long as the API is still compatible.) */

/* Macros are common for core and extensions */
#define Jim_FreeHashTableIterator(iter) Jim_Free(iter)

#ifndef __JIM_CORE__
# if defined JIM_EXTENSION || defined JIM_EMBEDDED
#  define JIM_API(x) (*x)
#  define JIM_STATIC
# else
#  define JIM_API(x) (*x)
#  define JIM_STATIC extern
# endif
#else
# define JIM_API(x) x
# define JIM_STATIC static
#endif /* __JIM_CORE__ */

/* Memory allocation */
JIM_STATIC void * JIM_API(Jim_Alloc) (int size);
JIM_STATIC void JIM_API(Jim_Free) (void *ptr);
JIM_STATIC char * JIM_API(Jim_StrDup) (const char *s);

/* evaluation */
JIM_STATIC int JIM_API(Jim_Eval)(Jim_Interp *interp, const char *script);
JIM_STATIC int JIM_API(Jim_EvalGlobal)(Jim_Interp *interp, const char *script);
JIM_STATIC int JIM_API(Jim_EvalFile)(Jim_Interp *interp, const char *filename);
JIM_STATIC int JIM_API(Jim_EvalObj) (Jim_Interp *interp, Jim_Obj *scriptObjPtr);
JIM_STATIC int JIM_API(Jim_EvalObjBackground) (Jim_Interp *interp,
        Jim_Obj *scriptObjPtr);
JIM_STATIC int JIM_API(Jim_EvalObjVector) (Jim_Interp *interp, int objc,
        Jim_Obj *const *objv);
JIM_STATIC int JIM_API(Jim_SubstObj) (Jim_Interp *interp, Jim_Obj *substObjPtr,
        Jim_Obj **resObjPtrPtr, int flags);

/* stack */
JIM_STATIC void JIM_API(Jim_InitStack)(Jim_Stack *stack);
JIM_STATIC void JIM_API(Jim_FreeStack)(Jim_Stack *stack);
JIM_STATIC int JIM_API(Jim_StackLen)(Jim_Stack *stack);
JIM_STATIC void JIM_API(Jim_StackPush)(Jim_Stack *stack, void *element);
JIM_STATIC void * JIM_API(Jim_StackPop)(Jim_Stack *stack);
JIM_STATIC void * JIM_API(Jim_StackPeek)(Jim_Stack *stack);
JIM_STATIC void JIM_API(Jim_FreeStackElements)(Jim_Stack *stack, void (*freeFunc)(void *ptr));

/* hash table */
JIM_STATIC int JIM_API(Jim_InitHashTable) (Jim_HashTable *ht,
        Jim_HashTableType *type, void *privdata);
JIM_STATIC int JIM_API(Jim_ExpandHashTable) (Jim_HashTable *ht,
        unsigned int size);
JIM_STATIC int JIM_API(Jim_AddHashEntry) (Jim_HashTable *ht, const void *key,
        void *val);
JIM_STATIC int JIM_API(Jim_ReplaceHashEntry) (Jim_HashTable *ht,
        const void *key, void *val);
JIM_STATIC int JIM_API(Jim_DeleteHashEntry) (Jim_HashTable *ht,
        const void *key);
JIM_STATIC int JIM_API(Jim_FreeHashTable) (Jim_HashTable *ht);
JIM_STATIC Jim_HashEntry * JIM_API(Jim_FindHashEntry) (Jim_HashTable *ht,
        const void *key);
JIM_STATIC int JIM_API(Jim_ResizeHashTable) (Jim_HashTable *ht);
JIM_STATIC Jim_HashTableIterator *JIM_API(Jim_GetHashTableIterator)
        (Jim_HashTable *ht);
JIM_STATIC Jim_HashEntry * JIM_API(Jim_NextHashEntry)
        (Jim_HashTableIterator *iter);

/* objects */
JIM_STATIC Jim_Obj * JIM_API(Jim_NewObj) (Jim_Interp *interp);
JIM_STATIC void JIM_API(Jim_FreeObj) (Jim_Interp *interp, Jim_Obj *objPtr);
JIM_STATIC void JIM_API(Jim_InvalidateStringRep) (Jim_Obj *objPtr);
JIM_STATIC void JIM_API(Jim_InitStringRep) (Jim_Obj *objPtr, const char *bytes,
        int length);
JIM_STATIC Jim_Obj * JIM_API(Jim_DuplicateObj) (Jim_Interp *interp,
        Jim_Obj *objPtr);
JIM_STATIC const char * JIM_API(Jim_GetString)(Jim_Obj *objPtr,
        int *lenPtr);
JIM_STATIC int JIM_API(Jim_Length)(Jim_Obj *objPtr);

/* string object */
JIM_STATIC Jim_Obj * JIM_API(Jim_NewStringObj) (Jim_Interp *interp,
        const char *s, int len);
JIM_STATIC Jim_Obj * JIM_API(Jim_NewStringObjNoAlloc) (Jim_Interp *interp,
        char *s, int len);
JIM_STATIC void JIM_API(Jim_AppendString) (Jim_Interp *interp, Jim_Obj *objPtr,
        const char *str, int len);
JIM_STATIC void JIM_API(Jim_AppendObj) (Jim_Interp *interp, Jim_Obj *objPtr,
        Jim_Obj *appendObjPtr);
JIM_STATIC void JIM_API(Jim_AppendStrings) (Jim_Interp *interp,
        Jim_Obj *objPtr, ...);
JIM_STATIC int JIM_API(Jim_StringEqObj) (Jim_Obj *aObjPtr,
        Jim_Obj *bObjPtr, int nocase);
JIM_STATIC int JIM_API(Jim_StringMatchObj) (Jim_Obj *patternObjPtr,
        Jim_Obj *objPtr, int nocase);
JIM_STATIC Jim_Obj * JIM_API(Jim_StringRangeObj) (Jim_Interp *interp,
        Jim_Obj *strObjPtr, Jim_Obj *firstObjPtr,
        Jim_Obj *lastObjPtr);
JIM_STATIC Jim_Obj * JIM_API(Jim_FormatString) (Jim_Interp *interp,
        Jim_Obj *fmtObjPtr, int objc, Jim_Obj *const *objv);
JIM_STATIC Jim_Obj * JIM_API(Jim_ScanString) (Jim_Interp *interp, Jim_Obj *strObjPtr,