/* ScummVM - Graphic Adventure Engine * * ScummVM is the legal property of its developers, whose names * are too numerous to list here. Please refer to the COPYRIGHT * file distributed with this source distribution. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. * * $URL$ * $Id$ * */ #ifndef SCI_ENGINE_VM_H #define SCI_ENGINE_VM_H /* VM and kernel declarations */ #include "common/serializer.h" #include "sci/engine/vm_types.h" // for reg_t #include "common/util.h" namespace Sci { class SegManager; struct EngineState; typedef int sci_version_t; enum MemObjectType { MEM_OBJ_INVALID = 0, MEM_OBJ_SCRIPT = 1, MEM_OBJ_CLONES = 2, MEM_OBJ_LOCALS = 3, MEM_OBJ_STACK = 4, MEM_OBJ_SYS_STRINGS = 5, MEM_OBJ_LISTS = 6, MEM_OBJ_NODES = 7, MEM_OBJ_HUNK = 8, MEM_OBJ_DYNMEM = 9, MEM_OBJ_STRING_FRAG = 10, MEM_OBJ_MAX // For sanity checking }; struct MemObject : public Common::Serializable { MemObjectType _type; int _segmgrId; /**< Internal value used by the seg_manager's hash map */ typedef void (*NoteCallback)(void *param, reg_t addr); // FIXME: Bad choice of name public: static MemObject *createMemObject(MemObjectType type); public: virtual ~MemObject() {} inline MemObjectType getType() const { return _type; } inline int getSegMgrId() const { return _segmgrId; } /** * Dereferences a raw memory pointer. * @param reg reference to dereference * @param size if not NULL, set to the theoretical maximum size of the referenced data block * @return the data block referenced */ virtual byte *dereference(reg_t pointer, int *size); /** * Finds the canonic address associated with sub_reg. * * For each valid address a, there exists a canonic address c(a) such that c(a) = c(c(a)). * This address "governs" a in the sense that deallocating c(a) will deallocate a. * * @param sub_addr base address whose canonic address is to be found */ virtual reg_t findCanonicAddress(SegManager *segmgr, reg_t sub_addr) { return sub_addr; } /** * Deallocates all memory associated with the specified address. * @param sub_addr address (within the given segment) to deallocate */ virtual void freeAtAddress(SegManager *segmgr, reg_t sub_addr) {} /** * Iterates over and reports all addresses within the current segment. * @param note Invoked for each address on which free_at_address() makes sense * @param param parameter passed to 'note' */ virtual void listAllDeallocatable(SegmentId segId, void *param, NoteCallback note) {} /** * Iterates over all references reachable from the specified object. * @param object object (within the current segment) to analyse * @param param parameter passed to 'note' * @param note Invoked for each outgoing reference within the object * Note: This function may also choose to report numbers (segment 0) as adresses */ virtual void listAllOutgoingReferences(EngineState *s, reg_t object, void *param, NoteCallback note) {} }; // TODO: Implement the following class struct StringFrag : public MemObject { virtual void saveLoadWithSerializer(Common::Serializer &ser); }; struct IntMapper; enum { SYS_STRINGS_MAX = 4, SYS_STRING_SAVEDIR = 0, SYS_STRING_PARSER_BASE = 1, MAX_PARSER_BASE = 64 }; struct SystemString { char *name; int max_size; reg_t *value; }; struct SystemStrings : public MemObject { SystemString strings[SYS_STRINGS_MAX]; public: SystemStrings() { memset(strings, 0, sizeof(strings)); } ~SystemStrings() { for (int i = 0; i < SYS_STRINGS_MAX; i++) { SystemString *str = &strings[i]; if (str->name) { free(str->name); str->name = NULL; free(str->value); str->value = NULL; str->max_size = 0; } } } virtual byte *dereference(reg_t pointer, int *size); virtual void saveLoadWithSerializer(Common::Serializer &ser); }; /** Number of bytes to be allocated for the stack */ #define VM_STACK_SIZE 0x1000 /** Maximum number of calls residing on the stack */ #define SCRIPT_MAX_EXEC_STACK 256 /** Maximum number of entries in the class table */ #define SCRIPT_MAX_CLASSTABLE_SIZE 256 /** Maximum number of cloned objects on the heap */ #define SCRIPT_MAX_CLONES 256 /** Object-relative offset of the selector area inside a script */ #define SCRIPT_SELECTOR_OFFSET 8 -8 /** Object-relative offset of the pointer to the underlying script's local variables */ #define SCRIPT_LOCALVARPTR_OFFSET 2 -8 /** Object-relative offset of the selector counter */ #define SCRIPT_SELECTORCTR_OFFSET 6 -8 /** Object-relative offset of the offset of the function area */ #define SCRIPT_FUNCTAREAPTR_OFFSET 4 -8 /** Offset that has to be added to the function area pointer */ #define SCRIPT_FUNCTAREAPTR_MAGIC 8 -8 /** Offset of the name pointer */ #define SCRIPT_NAME_OFFSET (s->version < SCI_VERSION_1_1 ? 14 -8 : 16) #define SCRIPT_NAME_SELECTOR (s->version < SCI_VERSION_1_1 ? 3 : 8) /** Object-relative offset of the -info- selector */ #define SCRIPT_INFO_OFFSET (s->version < SCI_VERSION_1_1 ? 12 -8 : 14) #define SCRIPT_INFO_SELECTOR (s->version < SCI_VERSION_1_1 ? 2 : 7) /** Flag fo the -info- selector */ #define SCRIPT_INFO_CLONE 0x0001 /** Flag for the -info- selector */ #define SCRIPT_INFO_CLASS 0x8000 /** Magical object identifier */ #define SCRIPT_OBJECT_MAGIC_NUMBER 0x1234 /** Offset of this identifier */ #define SCRIPT_OBJECT_MAGIC_OFFSET (s->version < SCI_VERSION_1_1 ? -8 : 0) /** Script-relative offset of the species ID */ #define SCRIPT_SPECIES_OFFSET 8 -8 #define SCRIPT_SUPERCLASS_OFFSET (s->version < SCI_VERSION_1_1 ? 10 -8 : 12) /*---------------------------------*/ /* Script selector index variables */ /*---------------------------------*/ #define SCRIPT_SPECIES_SELECTOR (s->version < SCI_VERSION_1_1 ? 0 : 5) #define SCRIPT_SUPERCLASS_SELECTOR (s->version < SCI_VERSION_1_1 ? 1 : 6) #define SCRIPT_CLASSSCRIPT_SELECTOR 4 /** Magic adjustment value for lofsa and lofss */ #define SCRIPT_LOFS_MAGIC 3 /** Stack pointer value: Use predecessor's value */ #define CALL_SP_CARRY NULL /** Types of selectors as returned by lookup_selector() below. */ enum SelectorType { kSelectorNone = 0, kSelectorVariable, kSelectorMethod }; struct Class { int script; /**< number of the script the class is in, -1 for non-existing */ reg_t reg; /**< offset; script-relative offset, segment: 0 if not instantiated */ }; #define RAW_GET_CLASS_INDEX(scr, reg) ((scr)->obj_indices->checkKey(reg.offset, false)) #define RAW_IS_OBJECT(datablock) (READ_LE_UINT16(((byte *) datablock) + SCRIPT_OBJECT_MAGIC_OFFSET) == SCRIPT_OBJECT_MAGIC_NUMBER) #define IS_CLASS(obj) (obj->_variables[SCRIPT_INFO_SELECTOR].offset & SCRIPT_INFO_CLASS) /** This struct is used to buffer the list of send calls in send_selector() */ struct CallsStruct { union { reg_t func; reg_t *var; } address; StackPtr argp; int argc; Selector selector; StackPtr sp; /**< Stack pointer */ int type; /**< Same as ExecStack.type */ }; struct LocalVariables : public MemObject { int script_id; /**< Script ID this local variable block belongs to */ Common::Array _locals; public: LocalVariables() { script_id = 0; } virtual byte *dereference(reg_t pointer, int *size); virtual reg_t findCanonicAddress(SegManager *segmgr, reg_t sub_addr); virtual void listAllOutgoingReferences(EngineState *s, reg_t object, void *param, NoteCallback note); virtual void saveLoadWithSerializer(Common::Serializer &ser); }; /** Clone has been marked as 'freed' */ #define OBJECT_FLAG_FREED (0x1 << 0) struct Object { int flags; reg_t pos; /**< Object offset within its script; for clones, this is their base */ int variable_names_nr; /**< Number of variable names, may be less than variables_nr */ int methods_nr; byte *base; /**< Points to a buffer all relative references (code, strings) point to */ byte *base_obj; /**< base + object offset within base */ uint16 *base_method; /**< Pointer to the method selector area for this object */ uint16 *base_vars; /**< Pointer to the varselector area for this object */ Common::Array _variables; }; struct CodeBlock { reg_t pos; int size; }; #define VM_OBJECT_GET_VARSELECTOR(obj, i) \ (s->version < SCI_VERSION_1_1 ? \ READ_LE_UINT16(obj->base_obj + obj->_variables.size() * 2 + i*2) : \ *(obj->base_vars + i)) #define VM_OBJECT_READ_PROPERTY(obj, i) (obj->_variables[i]) #define VM_OBJECT_GET_FUNCSELECTOR(obj, i) \ (s->version < SCI_VERSION_1_1 ? \ READ_LE_UINT16((byte *) (obj->base_method + i)) : \ READ_LE_UINT16((byte *) (obj->base_method + i*2 + 1))) #define VM_OBJECT_READ_FUNCTION(obj, i) \ (s->version < SCI_VERSION_1_1 ? \ make_reg(obj->pos.segment, \ READ_LE_UINT16((byte *) (obj->base_method \ + obj->methods_nr + 1 \ + i))) : \ make_reg(obj->pos.segment, \ READ_LE_UINT16((byte *) (obj->base_method \ + i * 2 + 2)))) struct Script : public MemObject { int nr; /**< Script number */ byte *buf; /**< Static data buffer, or NULL if not used */ size_t buf_size; size_t script_size; size_t heap_size; byte *synonyms; /**< Synonyms block or 0 if not present*/ byte *heap_start; /**< Start of heap if SCI1.1, NULL otherwise */ uint16 *export_table; /**< Abs. offset of the export table or 0 if not present */ IntMapper *obj_indices; int exports_nr; /**< Number of entries in the exports table */ int synonyms_nr; /**< Number of entries in the synonyms block */ int lockers; /**< Number of classes and objects that require this script */ /** * Table for objects, contains property variables. * Indexed by the value stored at SCRIPT_LOCALVARPTR_OFFSET, * see VM_OBJECT_[GS]ET_INDEX() */ Common::Array _objects; int locals_offset; int locals_segment; /**< The local variable segment */ LocalVariables *locals_block; Common::Array _codeBlocks; int relocated; bool _markedAsDeleted; public: Script() { nr = 0; buf = NULL; buf_size = 0; script_size = 0; heap_size = 0; synonyms = NULL; heap_start = NULL; export_table = NULL; obj_indices = NULL; locals_offset = 0; locals_segment = 0; locals_block = NULL; relocated = 0; _markedAsDeleted = 0; } ~Script() { freeScript(); } void freeScript(); virtual byte *dereference(reg_t pointer, int *size); virtual reg_t findCanonicAddress(SegManager *segmgr, reg_t sub_addr); virtual void freeAtAddress(SegManager *segmgr, reg_t sub_addr); virtual void listAllDeallocatable(SegmentId segId, void *param, NoteCallback note); virtual void listAllOutgoingReferences(EngineState *s, reg_t object, void *param, NoteCallback note); virtual void saveLoadWithSerializer(Common::Serializer &ser); // script lock operations /** Increments the number of lockers of this script by one. */ void incrementLockers(); /** Decrements the number of lockers of this script by one. */ void decrementLockers(); /** * Retrieves the number of locks held on this script. * @return the number of locks held on the previously identified script */ int getLockers() const; /** Sets the number of locks held on this script. */ void setLockers(int lockers); /** * Retrieves a pointer to the synonyms associated with this script * @return pointer to the synonyms, in non-parsed format. */ byte *getSynonyms() const; /** * Retrieves the number of synonyms associated with this script. * @return the number of synonyms associated with this script */ int getSynonymsNr() const; /** * Sets the script-relative offset of the exports table. * @param offset script-relative exports table offset */ void setExportTableOffset(int offset); /** * Sets the script-relative offset of the synonyms associated with this script. * @param offset script-relative offset of the synonyms block */ void setSynonymsOffset(int offset); /** * Sets the number of synonyms associated with this script, * @param nr number of synonyms, as to be stored within the script */ void setSynonymsNr(int nr); /** * Copies a byte string into a script's heap representation. * @param dst script-relative offset of the destination area * @param src pointer to the data source location * @param n number of bytes to copy */ void mcpyInOut(int dst, const void *src, size_t n); /** * Marks the script as deleted. * This will not actually delete the script. If references remain present on the * heap or the stack, the script will stay in memory in a quasi-deleted state until * either unreachable (resulting in its eventual deletion) or reloaded (resulting * in its data being updated). */ void markDeleted() { _markedAsDeleted = true; } /** * Marks the script as not deleted. */ void unmarkDeleted() { _markedAsDeleted = false; } /** * Determines whether the script is marked as being deleted. */ bool isMarkedAsDeleted() const { return _markedAsDeleted; } /** * Retrieves a 16 bit value from within a script's heap representation. * @param offset offset to read from * @return the value read from the specified location */ int16 getHeap(uint16 offset) const; }; /** Data stack */ struct DataStack : MemObject { int nr; /**< Number of stack entries */ reg_t *entries; public: DataStack() { nr = 0; entries = NULL; } ~DataStack() { free(entries); entries = NULL; } virtual byte *dereference(reg_t pointer, int *size); virtual reg_t findCanonicAddress(SegManager *segmgr, reg_t sub_addr); virtual void listAllOutgoingReferences(EngineState *s, reg_t object, void *param, NoteCallback note); virtual void saveLoadWithSerializer(Common::Serializer &ser); }; #define CLONE_USED -1 #define CLONE_NONE -1 typedef Object Clone; struct Node { reg_t pred; /**< Predecessor node */ reg_t succ; /**< Successor node */ reg_t key; reg_t value; }; /* List nodes */ struct List { reg_t first; reg_t last; }; struct Hunk { void *mem; unsigned int size; const char *type; }; template struct Table : public MemObject { typedef T value_type; struct Entry : public T { int next_free; /* Only used for free entries */ }; enum { HEAPENTRY_INVALID = -1 }; int first_free; /**< Beginning of a singly linked list for entries */ int entries_used; /**< Statistical information */ Common::Array _table; public: Table() { initTable(); } void initTable() { entries_used = 0; first_free = HEAPENTRY_INVALID; _table.clear(); } int allocEntry() { entries_used++; if (first_free != HEAPENTRY_INVALID) { int oldff = first_free; first_free = _table[oldff].next_free; _table[oldff].next_free = oldff; return oldff; } else { uint newIdx = _table.size(); _table.push_back(Entry()); _table[newIdx].next_free = newIdx; // Tag as 'valid' return newIdx; } } bool isValidEntry(int idx) { return idx >= 0 && (uint)idx < _table.size() && _table[idx].next_free == idx; } virtual void freeEntry(int idx) { if (idx < 0 || (uint)idx >= _table.size()) ::error("Table::freeEntry: Attempt to release invalid table index %d", idx); _table[idx].next_free = first_free; first_free = idx; entries_used--; } virtual void listAllDeallocatable(SegmentId segId, void *param, NoteCallback note); }; /* CloneTable */ struct CloneTable : public Table { virtual void freeAtAddress(SegManager *segmgr, reg_t sub_addr); virtual void listAllOutgoingReferences(EngineState *s, reg_t object, void *param, NoteCallback note); virtual void saveLoadWithSerializer(Common::Serializer &ser); }; /* NodeTable */ struct NodeTable : public Table { virtual void freeAtAddress(SegManager *segmgr, reg_t sub_addr); virtual void listAllOutgoingReferences(EngineState *s, reg_t object, void *param, NoteCallback note); virtual void saveLoadWithSerializer(Common::Serializer &ser); }; /* ListTable */ struct ListTable : public Table { virtual void freeAtAddress(SegManager *segmgr, reg_t sub_addr); virtual void listAllOutgoingReferences(EngineState *s, reg_t object, void *param, NoteCallback note); virtual void saveLoadWithSerializer(Common::Serializer &ser); }; /* HunkTable */ struct HunkTable : public Table { virtual void freeEntry(int idx) { Table::freeEntry(idx); free(_table[idx].mem); } virtual void saveLoadWithSerializer(Common::Serializer &ser); }; // Free-style memory struct DynMem : public MemObject { int _size; char *_description; byte *_buf; public: DynMem() : _size(0), _description(0), _buf(0) {} ~DynMem() { free(_description); _description = NULL; free(_buf); _buf = NULL; } virtual byte *dereference(reg_t pointer, int *size); virtual reg_t findCanonicAddress(SegManager *segmgr, reg_t sub_addr); virtual void listAllDeallocatable(SegmentId segId, void *param, NoteCallback note); virtual void saveLoadWithSerializer(Common::Serializer &ser); }; /** Contains selector IDs for a few selected selectors */ struct selector_map_t { Selector init; /**< Init function */ Selector play; /**< Play function (first function to be called) */ Selector replay; /**< Replay function */ Selector x, y, z; /**< Coordinates */ Selector priority; Selector view, loop, cel; /**< Description of a specific image */ Selector brLeft, brRight, brTop, brBottom; /**< Bounding Rectangle */ Selector xStep, yStep; /**< BR adjustments */ Selector nsLeft, nsRight, nsTop, nsBottom; /**< View boundaries ('now seen') */ Selector text, font; /**< Used by controls */ Selector type, state; /**< Used by contols as well */ Selector doit; /**< Called (!) by the Animate() system call */ Selector signal; /**< Used by Animate() to control a view's behaviour */ Selector underBits; /**< Used by the graphics subroutines to store backupped BG pic data */ /* The following selectors are used by the Bresenham syscalls: */ Selector canBeHere; /**< Funcselector: Checks for movement validity */ Selector client; /**< The object that wants to be moved */ Selector cycler; /**< The cycler of the client */ Selector dx, dy; /**< Deltas */ Selector edgeHit; Selector b_movCnt, b_i1, b_i2, b_di, b_xAxis, b_incr; /**< Various Bresenham vars */ Selector completed; Selector illegalBits; /**< Used by CanBeHere */ Selector dispose; Selector prevSignal; /**< Used by DoSound */ Selector message, modifiers; /**< Used by GetEvent */ Selector owner, handle; Selector cue; Selector number; Selector max, cursor; /**< Used by EditControl */ Selector mode; /**< Used by text controls (-> DrawControl()) */ Selector wordFail, syntaxFail, semanticFail; /**< Used by Parse() */ Selector claimed; /**< Used generally by the event mechanism */ Selector elements; /**< Used by SetSynonyms() */ Selector lsTop, lsBottom, lsRight, lsLeft; /**< Used by Animate() subfunctions and scroll list controls */ Selector baseSetter; /**< Alternative baseSetter */ Selector who, distance; /**< Used for 'chasing' movers */ Selector looper, mover, isBlocked, heading; /**< Used in DoAvoider */ Selector caller, moveDone, moveSpeed; /**< Used for DoBresen */ Selector delete_; /**< Called by Animate() to dispose a view object */ Selector vol; Selector pri; Selector min; /**< SMPTE time format */ Selector sec; Selector frame; Selector dataInc; Selector size; Selector palette; Selector cantBeHere; Selector nodePtr; Selector flags; Selector points; /**< Used by AvoidPath() */ Selector syncCue; /**< Used by DoSync() */ Selector syncTime; /**< Used by DoSync() */ }; struct ViewObject { reg_t obj; reg_t *signalp; /* Used only indirectly */ reg_t *underBitsp; /* The same goes for the handle storage */ int underBits; /* Copy of the underbits: Needed for cleanup */ int x, y; int priority; byte *view; int view_nr, loop, cel; /* view_nr is ised for save/restore */ int nsTop, nsLeft, nsRight, nsBottom; int real_y, z, index_nr; /* Used for sorting */ }; enum { VAR_GLOBAL = 0, VAR_LOCAL = 1, VAR_TEMP = 2, VAR_PARAM = 3 }; enum ExecStackType { EXEC_STACK_TYPE_CALL = 0, EXEC_STACK_TYPE_KERNEL = 1, EXEC_STACK_TYPE_VARSELECTOR = 2 }; struct ExecStack { reg_t objp; reg_t sendp; /**< Pointer to the object containing the invoked method */ union { reg_t *varp; /**< Variable pointer for read/write access */ reg_t pc; /**< Not accurate for the TOS element */ } addr; StackPtr fp; /**< Frame pointer */ StackPtr sp; /**< Stack pointer */ int argc; /* former variables[4]: [all other values are derived] */ StackPtr variables_argp; /**< Argument pointer */ SegmentId local_segment; /**< local variables etc. */ Selector selector; /**< The selector which was used to call or -1 if not applicable */ int origin; /**< The stack frame position the call was made from, or -1 if it was the initial call. */ ExecStackType type; }; enum BreakpointType { /** * Break when selector is executed. data contains (char *) selector name * (in the format Object::Method) */ BREAK_SELECTOR = 1, /** * Break when an exported function is called. data contains * script_no << 16 | export_no. */ BREAK_EXPORT = 2 }; struct Breakpoint { BreakpointType type; union { uint32 address; /**< Breakpoints on exports */ char *name; /**< Breakpoints on selector names */ } data; Breakpoint *next; }; /** Set this to 1 to activate script debugging */ extern int script_debug_flag; /** Set to 1 to move pc back to last position, even though action is executed */ extern int script_error_flag; /** Displays the numbers of scripts when they are (un)loaded */ extern int script_checkloads_flag; #define SCRIPT_ABORT_WITH_REPLAY 1025 /** * Set this to 1 to abort script execution immediately. Aborting will leave the * debug exec stack intact. * Set it to SCRIPT_ABORT_WITH_REPLAY to force a replay afterwards. */ extern int script_abort_flag; /** Number of kernel calls in between gcs; should be < 50000 */ #define GC_INTERVAL 32768 /** Initially GC_DELAY, can be set at runtime */ extern int script_gc_interval; /** Number of steps executed */ extern int script_step_counter; extern int _debugstate_valid; extern int _debug_seeking; extern int _debug_step_running; typedef int kernel_function(struct EngineState *s); extern kernel_function* kfuncs[]; extern int max_instance; /** * Executes function pubfunct of the specified script. * Parameters: (EngineState *) s: The state which is to be executed with * (uint16) script: The script which is called * (uint16) pubfunct: The exported script function which is to be called * (StackPtr) sp: Stack pointer position * (reg_t) calling_obj: The heap address of the object which executed the call * (uint16) argc: Number of arguments supplied * (StackPtr) argp: Pointer to the first supplied argument * Returns : (ExecStack *): A pointer to the new exec stack TOS entry */ ExecStack *execute_method(EngineState *s, uint16 script, uint16 pubfunct, StackPtr sp, reg_t calling_obj, uint16 argc, StackPtr argp); /** * Executes a "send" or related operation to a selector. * Parameters: (EngineState *) s: The EngineState to operate on * (reg_t) send_obj: Heap address of the object to send to * (reg_t) work_obj: Heap address of the object initiating the send * (StackPtr) sp: Stack pointer position * (int) framesize: Size of the send as determined by the "send" operation * (StackPtr) argp: Pointer to the beginning of the heap block containing the * data to be sent. This area is a succession of one or more * sequences of [selector_number][argument_counter] and then * "argument_counter" word entries with the parameter values. * Returns : (ExecStack *): A pointer to the new execution stack TOS entry */ ExecStack *send_selector(EngineState *s, reg_t send_obj, reg_t work_obj, StackPtr sp, int framesize, StackPtr argp); #define SCI_XS_CALLEE_LOCALS -1 /** * Adds an entry to the top of the execution stack. * * @param s The state with which to execute * @param pc The initial program counter * @param sp The initial stack pointer * @param objp Pointer to the beginning of the current object * @param argc Number of parameters to call with * @param argp Heap pointer to the first parameter * @param selector The selector by which it was called or * NULL_SELECTOR if n.a. For debugging. * @param sendp Pointer to the object which the message was sent to. * Equal to objp for anything but super. * @param origin Number of the execution stack element this entry was created by * (usually the current TOS number, except for multiple sends). * @param local_segment The segment to use for local variables, * or SCI_XS_CALLEE_LOCALS to use obj's segment. * @return a pointer to the new exec stack TOS entry */ ExecStack *add_exec_stack_entry(EngineState *s, reg_t pc, StackPtr sp, reg_t objp, int argc, StackPtr argp, Selector selector, reg_t sendp, int origin, SegmentId local_segment); /** * Adds one varselector access to the execution stack. * Parameters: (EngineState *) s: The EngineState to use * (reg_t) objp: Pointer to the object owning the selector * (int) argc: 1 for writing, 0 for reading * (StackPtr) argp: Pointer to the address of the data to write -2 * (int) selector: Selector name * (reg_t *) address: Heap address of the selector * (int) origin: Stack frame which the access originated from * Returns : (ExecStack *): Pointer to the new exec-TOS element * This function is called from send_selector only. */ ExecStack *add_exec_stack_varselector(EngineState *s, reg_t objp, int argc, StackPtr argp, Selector selector, reg_t *address, int origin); void run_vm(EngineState *s, int restoring); /* Executes the code on s->heap[pc] until it hits a 'ret' operation while (stack_base == stack_pos) ** Parameters: (EngineState *) s: The state to use ** (int) restoring: 1 if s has just been restored, 0 otherwise ** Returns : (void) ** This function will execute SCI bytecode. It requires s to be set up ** correctly. */ void vm_handle_fatal_error(EngineState *s, int line, const char *file); /* Handles a fatal error condition ** Parameters: (EngineState *) s: The state to recover from ** (int) line: Source code line number the error occured in ** (const char *) file: File the error occured in */ void script_debug(EngineState *s, reg_t *pc, StackPtr *sp, StackPtr *pp, reg_t *objp, int *restadjust, SegmentId *segids, reg_t **variables, reg_t **variables_base, int *variables_nr, int bp); /* Debugger functionality ** Parameters: (EngineState *) s: The state at which debugging should take place ** (reg_t *) pc: Pointer to the program counter ** (StackPtr *) sp: Pointer to the stack pointer ** (StackPtr *) pp: Pointer to the frame pointer ** (reg_t *) objp: Pointer to the object base pointer ** (int *) restadjust: Pointer to the &rest adjustment value ** (SegmentId *) segids: four-element array containing segment IDs for locals etc. ** (reg_t **) variables: four-element array referencing registers for globals etc. ** (reg_t **) variables_base: four-element array referencing ** register bases for temps etc. ** (int *) variables_nr: four-element array giving sizes for params etc. (may be NULL) ** (int) bp: Flag, set to 1 when a breakpoint is triggered ** Returns : (void) */ int script_init_engine(EngineState *s, sci_version_t version); /* Initializes a EngineState block ** Parameters: (EngineState *) s: The state to initialize ** Returns : 0 on success, 1 if vocab.996 (the class table) is missing or corrupted */ void script_set_gamestate_save_dir(EngineState *s, const char *path); /* Sets the gamestate's save_dir to the parameter path ** Parameters: (EngineState *) s: The state to set ** (const char *) path: Path where save_dir will point to ** Returns : (void) */ void script_free_engine(EngineState *s); /* Frees all additional memory associated with a EngineState block ** Parameters: (EngineState *) s: The EngineState whose elements should be cleared ** Returns : (void) */ void script_free_vm_memory(EngineState *s); /* Frees all script memory (heap, hunk, and class tables). ** Parameters: (EngineState *) s: The EngineState to free ** Returns : (void) ** This operation is implicit in script_free_engine(), but is required for restoring ** the game state. */ SelectorType lookup_selector(EngineState *s, reg_t obj, Selector selectorid, reg_t **vptr, reg_t *fptr); /* Looks up a selector and returns its type and value ** Parameters: (EngineState *) s: The EngineState to use ** (reg_t) obj: Address of the object to look the selector up in ** (Selector) selectorid: The selector to look up ** Returns : (SelectorType) kSelectorNone if the selector was not found in the object or its superclasses. ** kSelectorVariable if the selector represents an object-relative variable ** kSelectorMethod if the selector represents a method ** (reg_t *) *vptr: A pointer to the storage space associated with the selector, if ** it is a variable ** (reg_t) *fptr: A reference to the function described by that selector, if it is ** a valid function selector. ** *vptr is written to iff it is non-NULL and the selector indicates a property of the object. ** *fptr is written to iff it is non-NULL and the selector indicates a member function of that object. */ enum { SCRIPT_GET_DONT_LOAD = 0, /**< Fail if not loaded */ SCRIPT_GET_LOAD = 1, /**< Load, if neccessary */ SCRIPT_GET_LOCK = 3 /**< Load, if neccessary, and lock */ }; SegmentId script_get_segment(EngineState *s, int script_id, int load); /* Determines the segment occupied by a certain script ** Parameters: (EngineState *) s: The state to operate on ** (int) script_id: The script in question ** (int) load: One of SCRIPT_GET_* ** Returns : The script's segment, or 0 on failure */ reg_t script_lookup_export(EngineState *s, int script_nr, int export_index); /* Looks up an entry of the exports table of a script ** Parameters: (EngineState *) s: The state to operate on ** (int) script_nr: The script to look up in ** Returns : (int) export_index: index of the export entry to look up */ int script_instantiate(EngineState *s, int script_nr); /* Makes sure that a script and its superclasses get loaded to the heap ** Parameters: (EngineState *) s: The state to operate on ** (int) script_nr: The script number to load ** Returns : (int) The script's segment ID or 0 if out of heap ** If the script already has been loaded, only the number of lockers is increased. ** All scripts containing superclasses of this script aret loaded recursively as well, ** unless 'recursive' is set to zero. ** The complementary function is "script_uninstantiate()" below. */ void script_uninstantiate(EngineState *s, int script_nr); /* Decreases the numer of lockers of a script and unloads it if that number reaches zero ** Parameters: (EngineState *) s: The state to operate on ** (int) script_nr: The script number that is requestet to be unloaded ** Returns : (void) ** This function will recursively unload scripts containing its superclasses, if those ** aren't locked by other scripts as well. */ int game_init(EngineState *s); /* Initializes an SCI game ** Parameters: (EngineState *) s: The state to operate on ** Returns : (int): 0 on success, 1 if an error occured. ** This function must be run before script_run() is executed. ** Graphics data is initialized iff s->gfx_state != NULL. */ int game_init_graphics(EngineState *s); /* Initializes the graphics part of an SCI game ** Parameters: (EngineState *) s: The state to initialize the graphics in ** Returns : (int) 0 on success, 1 if an error occured ** This function may only be called if game_init() did not initialize ** the graphics data. */ int game_init_sound(EngineState *s, int sound_flags); /* Initializes the sound part of an SCI game ** Parameters: (EngineState *) s: The state to initialize the sound in ** (int) sound_flags: Flags to pass to the sound subsystem ** Returns : (int) 0 on success, 1 if an error occured ** This function may only be called if game_init() did not initialize ** the graphics data. */ int game_run(EngineState **s); /* Runs an SCI game ** Parameters: (EngineState **) s: Pointer to the pointer of the state to operate on ** Returns : (int): 0 on success, 1 if an error occured. ** This is the main function for SCI games. It takes a valid state, loads script 0 to it, ** finds the game object, allocates a stack, and runs the init method of the game object. ** In layman's terms, this runs an SCI game. ** By the way, *s may be changed during the game, e.g. if a game state is restored. */ int game_restore(EngineState **s, char *savegame_name); /* Restores an SCI game state and runs the game ** Parameters: (EngineState **) s: Pointer to the pointer of the state to operate on ** (char *) savegame_name: Name of the savegame to restore ** Returns : (int): 0 on success, 1 if an error occured. ** This restores a savegame; otherwise, it behaves just like game_run(). */ int game_exit(EngineState *s); /* Uninitializes an initialized SCI game ** Parameters: (EngineState *) s: The state to operate on ** Returns : (int): 0 on success, 1 if an error occured. ** This function should be run after each script_run() call. */ void quit_vm(); /* Instructs the virtual machine to abort ** Paramteres: (void) ** Returns : (void) */ void script_map_selectors(EngineState *s, selector_map_t *map); /* Maps special selectors ** Parameters: (EngineState *) s: The state from which the selector information should be taken ** (selector_map_t *) map: Pointer to the selector map to map ** Returns : (void) ** Called by script_run(); */ int script_map_kernel(EngineState *s); /* Maps kernel functions ** Parameters: (EngineState *) s: The state which the _kernelNames are retrieved from ** Returns : (void) ** This function reads from and writes to s. It is called by script_run(). */ reg_t kalloc(EngineState *s, const char *type, int space); /* Allocates "kernel" memory and returns a handle suitable to be passed on to SCI scripts ** Parameters: (EngineState *) s: Pointer to the EngineState to operate on ** (const char *) type: A free-form type description string (static) ** (int) space: The space to allocate ** Returns : (reg_t) The handle */ bool has_kernel_function(EngineState *s, const char *kname); /* Detects whether a particular kernel function is required in the game ** Parameters: (EngineState *) s: Pointer to the EngineState to operate on ** (const char *) kname: The name of the desired kernel function ** Returns : (bool) 1 if the kernel function is listed in the kernel table, ** 0 otherwise */ byte *kmem(EngineState *s, reg_t handle); /* Returns a pointer to "kernel" memory based on the handle ** Parameters: (EngineState *) s: Pointer to the EngineState to operate on ** (reg_t) handle: The handle to use ** Returns : (byte *) A pointer to the allocated memory */ int kfree(EngineState *s, reg_t handle); /* Frees all "kernel" memory associated with a handle ** Parameters: (EngineState *) s: Pointer to the EngineState to operate on ** (reg_t) handle: The handle to free ** Returns : (int) 0 on success, 1 otherwise */ const char *obj_get_name(EngineState *s, reg_t pos); /* Determines the name of an object ** Parameters: (EngineState *) s: Pointer to the EngineState to operate on ** (reg_t) pos: Location of the object whose name we want to ** inspect ** Returns : (const char *) A name for that object, or a string describing ** an error that occured while looking it up ** The string is stored in a static buffer and need not be freed (neither ** may it be modified). */ Object *obj_get(EngineState *s, reg_t offset); /* Retrieves an object from the specified location ** Parameters: (EngineState *) s: Pointer to the EngineState to operate on ** (reg_t) offset: The object's offset ** Returns : (Object *) The object in question, or NULL if there is none */ } // End of namespace Sci #endif // SCI_ENGINE_VM_H