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yap-6.3/CXX/yapq.hh
Vítor Santos Costa a6e578090c C-interface
2018-09-18 19:27:10 +01:00

384 lines
11 KiB
C++

/**
* @file yapq.hh
*
* @defgroup yap-cplus-query-handling Query Handling in the YAP interface.
* @brief Engine and Query Management
*
* @ingroup yap-cplus-interface
*
* @{
*
* These classes wrap engine and query. An engine is an environment where we
* can rum Prolog, that is, where we can run queries.
*
* Also, supports callbacks and engine configuration.
*
*/
#ifndef YAPQ_HH
#define YAPQ_HH 1
class X_API YAPPredicate;
/**
Queries and engines
*/
#if __ANDROID__
#endif
/**
* @brief Queries
*
* interface to a YAP Query;
* uses an SWI-like status info internally.
*/
class X_API YAPQuery : public YAPPredicate {
bool q_open;
int q_state;
yhandle_t q_handles;
struct yami *q_p, *q_cp;
int q_flags;
YAP_dogoalinfo q_h;
YAPPairTerm names;
Term goal;
CELL *nts;
// temporaries
YAPError *e;
inline void setNext() { // oq = LOCAL_execution;
// LOCAL_execution = this;
q_open = true;
q_state = 0;
q_flags = true; // PL_Q_PASS_EXCEPTION;
q_p = P;
q_cp = CP;
// make sure this is safe
q_handles = LOCAL_CurSlot;
};
void openQuery();
PredEntry *rewriteUndefQuery();
public:
YAPQuery() {
goal = TermTrue;
openQuery();
};
inline ~YAPQuery() { close(); }
/// main constructor, uses a predicate and an array of terms
///
/// It is given a YAPPredicate _p_ , and an array of terms that must have at
/// least
/// the same arity as the functor.
YAPQuery(YAPPredicate p, YAPTerm t[]);
/// full constructor,
///
///
/// It is given a functor, module, and an array of terms that must have at
/// least
/// the same arity as the functor.
YAPQuery(YAPFunctor f, YAPTerm mod, YAPTerm t[]);
/// functor/term constructor,
///
/// It is given a functor, and an array of terms that must have at least
/// the same arity as the functor. Works within the current module.
// YAPQuery(YAPFunctor f, YAPTerm t[]);
/// string constructor without varnames
///
/// It is given a string, calls the parser and obtains a Prolog term that
/// should be a callable
/// goal.
inline YAPQuery(const char *s) : YAPPredicate(s, goal, names, (nts = &ARG1)) {
__android_log_print(ANDROID_LOG_INFO, "YAPDroid", "got game %ld",
LOCAL_CurSlot);
openQuery();
};
// inline YAPQuery() : YAPPredicate(s, tgoal, tnames)
// {
// __android_log_print(ANDROID_LOG_INFO, "YAPDroid", "got game %ld",
// if (!ap)
// return;
// __android_log_print(ANDROID_LOG_INFO, "YAPDroid", "%s", vnames.text());
// goal = YAPTerm(tgoal);
// names = YAPPairTerm(tnames);
// openQuery(tgoal);
// };
/// string constructor with just an atom
///
/// It i;
///};
/// build a query from a term
YAPQuery(YAPTerm t) : YAPPredicate((goal = t.term()), (nts = &ARG1)) {
BACKUP_MACHINE_REGS();
openQuery();
names = YAPPairTerm(TermNil);
RECOVER_MACHINE_REGS();
}
/// set flags for query execution, currently only for exception handling
void setFlag(int flag) { q_flags |= flag; }
/// reset flags for query execution, currently only for exception handling
void resetFlag(int flag) { q_flags &= ~flag; }
/// first query
///
/// actually implemented by calling the next();
inline bool first() { return next(); }
/// ask for the next solution of the current query
/// same call for every solution
bool next();
/// does this query have open choice-points?
/// or is it deterministic?
bool deterministic();
/// represent the top-goal
const char *text();
/// remove alternatives in the current search space, and finish the current
/// query
/// finish the current query: undo all bindings.
void close();
/// query variables.
void cut();
Term namedVars() { return names.term(); };
YAPPairTerm namedVarTerms() { return names; };
/// query variables, but copied out
std::vector<Term> namedVarsVector() { return names.listToArray(); };
/// convert a ref to a binding.
YAPTerm getTerm(yhandle_t t);
/// simple YAP Query;
/// just calls YAP and reports success or failure, Useful when we just
/// want things done, eg YAPCommand("load_files(library(lists), )")
inline bool command() {
bool rc = next();
close();
return rc;
};
};
// Java support
/// This class implements a callback Prolog-side. It will be inherited by the
/// Java or Python
/// class that actually implements the callback.
class X_API YAPCallback {
public:
virtual ~YAPCallback() {}
virtual void run() { LOG("callback"); }
virtual void run(char *s) {}
};
/// @brief Setup all arguments to a new engine
struct X_API YAPEngineArgs : YAP_init_args {
public:
YAPEngineArgs() {
// const std::string *s = new std::string("startup.yss");
Embedded = true;
install = false;
Yap_InitDefaults(this, nullptr, 0, nullptr);
#if YAP_PYTHON
Embedded = true;
python_in_python = Py_IsInitialized();
#endif
#if __ANDROID__
#endif
};
inline void setEmbedded(bool fl) { Embedded = fl; };
inline bool getEmbedded() { return Embedded; };
inline void setStackSize(bool fl) { StackSize = fl; };
inline bool getStackSize() { return StackSize; };
inline void setTrailSize(bool fl) { TrailSize = fl; };
inline bool getTrailSize() { return TrailSize; };
inline bool getMStackSize() { return StackSize; };
inline void setMaxTrailSize(bool fl) { MaxTrailSize = fl; };
inline bool getMaxTrailSize() { return MaxTrailSize; };
inline void createSavedState(bool fl) { install = fl; };
inline bool creatingSavedState() { return install; };
inline void setPLDIR(const char *fl) {
LIBDIR = (const char *)malloc(strlen(fl) + 1);
strcpy((char *)LIBDIR, fl);
};
inline const char *getPLDIR() { return PLDIR; };
inline void setINPUT_STARTUP(const char *fl) {
INPUT_STARTUP = (const char *)malloc(strlen(fl) + 1);
strcpy((char *)INPUT_STARTUP, fl);
};
inline const char *getINPUT_STARTUP() { return INPUT_STARTUP; };
inline void setOUTPUT_RESTORE(const char *fl) {
OUTPUT_STARTUP = (const char *)malloc(strlen(fl) + 1);
strcpy((char *)OUTPUT_STARTUP, fl);
};
inline const char *getOUTPUT_STARTUP() { return OUTPUT_STARTUP; };
inline void setBOOTFILE(const char *fl) {
BOOTFILE = (const char *)malloc(strlen(fl) + 1);
strcpy((char *)BOOTFILE, fl);
};
inline const char *getBOOTFILE() { return BOOTFILE; };
inline void setPrologBOOTSTRAP(const char *fl) {
BOOTSTRAP = (const char *)malloc(strlen(fl) + 1);
strcpy((char *)BOOTSTRAP, fl);
};
inline const char *getBOOTSTRAP() { return BOOTSTRAP; };
inline void setPrologGoal(const char *fl) { PrologGoal = fl; };
inline const char *getPrologGoal() { return PrologGoal; };
inline void setPrologTopLevelGoal(const char *fl) {
PrologTopLevelGoal = fl;
};
inline const char *getPrologTopLevelGoal() { return PrologTopLevelGoal; };
inline void setHaltAfterBoot(bool fl) { HaltAfterBoot = fl; };
inline bool getHaltAfterBoot() { return HaltAfterBoot; };
inline void setFastBoot(bool fl) { FastBoot = fl; };
inline bool getFastBoot() { return FastBoot; };
inline void setArgc(int fl) { Argc = fl; };
inline int getArgc() { return Argc; };
inline void setArgv(char **fl) { Argv = fl; };
inline char **getArgv() { return Argv; };
};
/**
* @brief YAP Engine: takes care of the execution environment
where we can go executing goals.
*
*
*/
class YAPEngine {
private:
YAPEngineArgs *engine_args;
YAPCallback *_callback;
YAPError yerror;
void doInit(YAP_file_type_t BootMode, YAPEngineArgs *cargs);
YAP_dogoalinfo q;
YAPError e;
PredEntry *rewriteUndefEngineQuery(PredEntry *ap, Term &t, Term tmod);
public:
/// construct a new engine; may use a variable number of arguments
YAPEngine(YAPEngineArgs *cargs) {
engine_args = cargs;
// doInit(cargs->boot_file_type);
doInit(YAP_QLY, cargs);
}; /// construct a new engine, including aaccess to callbacks
/// construct a new engine using argc/argv list of arguments
YAPEngine(int argc, char *argv[],
YAPCallback *callback = (YAPCallback *)NULL);
/// kill engine
~YAPEngine() { delYAPCallback(); };
/// remove current callback
void delYAPCallback() { _callback = 0; };
/// set a new callback
void setYAPCallback(YAPCallback *cb) {
delYAPCallback();
_callback = cb;
};
/// execute the callback.
////void run() { if (_callback) _callback.run(); }
/// execute the callback with a text argument.
void run(char *s) {
if (_callback)
_callback->run(s);
}
/// stop yap
void close() { Yap_exit(0); }
/// execute the callback with a text argument.
bool hasError() { return LOCAL_Error_TYPE != YAP_NO_ERROR; }
/// build a query on the engine
YAPQuery *query(const char *s) { return new YAPQuery(s); };
/// build a query from a term
YAPQuery *query(YAPTerm t) { return new YAPQuery(t); };
/// build a query from a Prolog term (internal)
YAPQuery *qt(Term t) { return new YAPQuery(YAPTerm(t)); };
/// current module for the engine
Term Yap_CurrentModule() { return CurrentModule; }
/// given a handle, fetch a term from the engine
inline YAPTerm getTerm(yhandle_t h) { return YAPTerm(h); }
/// current directory for the engine
bool call(YAPPredicate ap, YAPTerm ts[]);
/// current directory for the engine
bool goal(YAPTerm Yt, YAPModule module, bool release = false) {
return mgoal(Yt.term(), module.term(), release);
};
/// ru1n a goal in a module.
///
/// By default, memory will only be fully
/// recovered on backtracking. The release option ensures
/// backtracking is called at the very end.
bool mgoal(Term t, Term tmod, bool release = false);
/// current directory for the engine
bool goal(Term t, bool release = false) {
return mgoal(t, Yap_CurrentModule(), release);
}
/// reset Prolog state
void reSet();
/// assune that there are no stack pointers, just release memory
// for last execution
void release();
const char *currentDir() {
char dir[1024];
std::string s = Yap_getcwd(dir, 1024 - 1);
return s.c_str();
};
/// report YAP version as a string
const char *version() {
std::string s = Yap_version();
return s.c_str();
};
//> call a deterninistic predicate: the user will construct aterm of
//> arity N-1. YAP adds an extra variable which will have the
//> output.
YAPTerm funCall(YAPTerm t) { return YAPTerm(fun(t.term())); };
Term fun(Term t);
//> set a StringFlag, usually a path
//>
bool setStringFlag(std::string arg, std::string path) {
return setYapFlag(MkAtomTerm(Yap_LookupAtom(arg.data())),
MkAtomTerm(Yap_LookupAtom(path.data())));
};
Term top_level(std::string s);
Term next_answer(YAPQuery *&Q);
};
#endif /* YAPQ_HH */
/// @}