/*************************************************************************
* *
* YAP Prolog *
* *
* Yap Prolog was developed at NCCUP - Universidade do Porto *
* *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
* *
**************************************************************************
* *
* File: readline.c *
* Last rev: 5/2/88 *
* mods: *
* comments: Input/Output C implemented predicates *
* *
*************************************************************************/
/**
* @file console.c
* @author VITOR SANTOS COSTA <vsc@VITORs-MBP.lan>
* @date Wed Jan 20 00:56:23 2016
*
* @brief
*
*
*/
/*
* This file includes the interface to the console IO, tty style. Refer also to
the readline library.
* @defgroup console Support for console-based interaction.
* @ingroup InputOutput
*/
#include "sysbits.h"
static Int prompt(USES_REGS1);
static Int prompt1(USES_REGS1);
static int ConsoleGetc(int);
static int ConsolePutc(int, int);
bool Yap_DoPrompt(StreamDesc *s) {
if (s->status & Tty_Stream_f) {
if (GLOBAL_Stream[LOCAL_c_input_stream].status & Tty_Stream_f &&
GLOBAL_Stream[LOCAL_c_error_stream].status & Tty_Stream_f) {
return LOCAL_newline;
}
}
return false;
}
/* check if we read a newline or an EOF */
int console_post_process_read_char(int ch, StreamDesc *s) {
/* the character is also going to be output by the console handler */
console_count_output_char(ch, GLOBAL_Stream + LOCAL_c_error_stream);
if (ch == '\r') {
s->linepos = 0;
LOCAL_newline = true;
} else
if (ch == '\n') {
CACHE_REGS
++s->linecount;
++s->charcount;
s->linepos = 0;
LOCAL_newline = true;
} else {
CACHE_REGS
++s->charcount;
++s->linepos;
LOCAL_newline = false;
}
return ch;
}
bool is_same_tty(FILE *f1, FILE *f2) {
#if HAVE_TTYNAME
return ttyname_r(fileno(f1), LOCAL_FileNameBuf, YAP_FILENAME_MAX - 1) ==
ttyname_r(fileno(f2), LOCAL_FileNameBuf, YAP_FILENAME_MAX - 1);
#endif
// assume a single console, for now
return true;
}
static Int is_same_tty2(USES_REGS1) { /* 'prompt(Atom) */
int sni = Yap_CheckStream(ARG1, Input_Stream_f, "put/2");
int sno = Yap_CheckStream(ARG2, Output_Stream_f, "put/2");
bool out = (GLOBAL_Stream[sni].status & Tty_Stream_f) &&
(GLOBAL_Stream[sno].status & Tty_Stream_f) &&
is_same_tty(GLOBAL_Stream[sno].file, GLOBAL_Stream[sni].file);
UNLOCK(GLOBAL_Stream[sno].streamlock);
UNLOCK(GLOBAL_Stream[sni].streamlock);
return out;
}
void Yap_ConsoleOps(StreamDesc *s) {
/* the putc routine only has to check it is putting out a newline */
s->stream_putc = ConsolePutc;
s->stream_getc = ConsoleGetc;
#if USE_READLINE
/* if a tty have a special routine to call readline */
if ((s->status & Readline_Stream_f) && trueGlobalPrologFlag(READLINE_FLAG)) {
if (Yap_ReadlineOps(s))
return;
}
#endif
}
/* static */
static int ConsolePutc(int sno, int ch) {
StreamDesc *s = &GLOBAL_Stream[sno];
if (ch == 10) {
#if MAC || _WIN32
fputs("\n", s->file);
#else
putc('\n', s->file);
#endif
LOCAL_newline = true;
} else
putc(ch, s->file);
#if MAC || _WIN32
fflush( NULL );
#endif
console_count_output_char(ch, s);
return ((int)ch);
}
/* send a prompt, and use the system for internal buffering. Speed is
not of the essence here !!! */
static int ConsoleGetc(int sno) {
CACHE_REGS
register StreamDesc *s = &GLOBAL_Stream[sno];
int ch;
restart:
/* keep the prompt around, just in case, but don't actually
show it in silent mode */
if (Yap_DoPrompt(s)) {
if (!silentMode()) {
char *cptr = LOCAL_Prompt, ch;
/* use the default routine */
while ((ch = *cptr++) != '\0') {
GLOBAL_Stream[StdErrStream].stream_putc(StdErrStream, ch);
}
}
Yap_clearInput(LOCAL_c_error_stream);
strncpy(LOCAL_Prompt, (char *)RepAtom(LOCAL_AtPrompt)->StrOfAE, MAX_PROMPT);
LOCAL_newline = FALSE;
}
#if HAVE_SIGINTERRUPT
siginterrupt(SIGINT, TRUE);
#endif
LOCAL_PrologMode |= ConsoleGetcMode;
ch = fgetc(s->file);
#if HAVE_SIGINTERRUPT
siginterrupt(SIGINT, FALSE);
#endif
if (LOCAL_PrologMode & InterruptMode) {
Yap_external_signal(0, YAP_INT_SIGNAL);
LOCAL_PrologMode &= ~ConsoleGetcMode;
LOCAL_newline = TRUE;
if (LOCAL_PrologMode & AbortMode) {
Yap_Error(ABORT_EVENT, TermNil, "");
LOCAL_ErrorMessage = "Abort";
return EOF;
}
goto restart;
} else {
LOCAL_PrologMode &= ~ConsoleGetcMode;
}
if (ch == EOF)
return EOF;
return ch;
}
/** @pred prompt1(+ _A__)
Changes YAP input prompt for the .
*/
static Int prompt1(USES_REGS1) { /* prompt1(Atom) */
Term t = Deref(ARG1);
Atom a;
if (IsVarTerm(t) || !IsAtomTerm(t))
return (FALSE);
LOCAL_AtPrompt = a = AtomOfTerm(t);
if (strlen((char *)RepAtom(a)->StrOfAE) > MAX_PROMPT) {
Yap_Error(SYSTEM_ERROR_INTERNAL, t, "prompt %s is too long",
RepAtom(a)->StrOfAE);
return (FALSE);
}
strncpy(LOCAL_Prompt, (char *)RepAtom(a)->StrOfAE, MAX_PROMPT);
return (TRUE);
}
/** @pred prompt(- _A_,+ _B_)
Changes YAP input prompt from _A_ to _B_, active on *next* standard input
interaction.
*/
static Int prompt(USES_REGS1) { /* prompt(Old,New) */
Term t = Deref(ARG2);
Atom a;
if (!Yap_unify_constant(ARG1, MkAtomTerm(LOCAL_AtPrompt)))
return (FALSE);
if (IsVarTerm(t) || !IsAtomTerm(t))
return (FALSE);
a = AtomOfTerm(t);
if (strlen(RepAtom(a)->StrOfAE) > MAX_PROMPT) {
Yap_Error(SYSTEM_ERROR_INTERNAL, t, "prompt %s is too long",
RepAtom(a)->StrOfAE);
return false;
}
strncpy(LOCAL_Prompt, (char *)RepAtom(LOCAL_AtPrompt)->StrOfAE, MAX_PROMPT);
LOCAL_AtPrompt = a;
return (TRUE);
}
/** @pred ensure_prompting
Make sure we have a prompt at this point, even if we have to
introduce a new line.
*/
static Int ensure_prompting(USES_REGS1) { /* prompt(Old,New) */
if (!LOCAL_newline) {
GLOBAL_Stream[2].stream_wputc(2, 10); // hack!
}
return true;
}
int Yap_GetCharForSIGINT(void) {
CACHE_REGS
int ch;
#if USE_READLINE
if (trueGlobalPrologFlag(READLINE_FLAG) ||
(ch = Yap_ReadlineForSIGINT()) == 0)
#endif
{ /* ask for a new line */
fprintf(stderr, "Action (h for help): ");
ch = getc(stdin);
/* first process up to end of line */
while ((fgetc(stdin)) != '\n')
;
}
LOCAL_newline = TRUE;
fflush(NULL);
return ch;
}
void Yap_InitConsole(void) {
CACHE_REGS
LOCAL_newline = true;
Yap_InitCPred("prompt", 1, prompt1, SafePredFlag | SyncPredFlag);
Yap_InitCPred("prompt1", 1, prompt1, SafePredFlag | SyncPredFlag);
Yap_InitCPred("$is_same_tty", 2, is_same_tty2,
SafePredFlag | SyncPredFlag | HiddenPredFlag);
Yap_InitCPred("prompt", 2, prompt, SafePredFlag | SyncPredFlag);
Yap_InitCPred("$ensure_prompting", 0, ensure_prompting,
SafePredFlag | SyncPredFlag);
}