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yap-6.3/os/readutil.c
Vitor Santos Costa b1067dcc34 error handling
2017-08-27 22:22:34 +01:00

302 lines
8.5 KiB
C

/*************************************************************************
* *
* YAP Prolog *
* *
* Yap Prolog was developed at NCCUP - Universidade do Porto *
* *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
* *
**************************************************************************
* *
* File: readutil.c *
* Last rev: 2/8/06 *
* mods: *
* comments: readutil library support *
* *
*************************************************************************/
#ifdef SCCS
static char SccsId[] = "%W% %G%";
#endif
#include "Yap.h"
#include "YapHeap.h"
#include "YapText.h"
#include "Yatom.h"
#include "encoding.h"
#include "iopreds.h"
#include "yapio.h"
/// @addtogroup readutil
static Int rl_to_codes(Term TEnd, int do_as_binary, int arity USES_REGS) {
int sno = Yap_CheckStream(ARG1, Input_Stream_f, "read_line_to_codes/2");
StreamDesc *st = GLOBAL_Stream + sno;
Int status;
UInt max_inp, buf_sz, sz;
unsigned char *buf;
bool binary_stream;
int ch;
if (sno < 0)
return false;
status = GLOBAL_Stream[sno].status;
binary_stream = GLOBAL_Stream[sno].status & Binary_Stream_f;
if (status & Eof_Stream_f) {
UNLOCK(GLOBAL_Stream[sno].streamlock);
return Yap_unify_constant(ARG2, MkAtomTerm(AtomEof));
}
max_inp = (ASP - HR) / 2 - 1024;
buf = (unsigned char *)TR;
buf_sz = (unsigned char *)LOCAL_TrailTop - buf;
while (true) {
if (buf_sz > max_inp) {
buf_sz = max_inp;
}
if (do_as_binary && !binary_stream) {
GLOBAL_Stream[sno].status |= Binary_Stream_f;
}
if (st->status & Binary_Stream_f) {
char *b = (char *)TR;
sz = fread(b, 1, buf_sz, GLOBAL_Stream[sno].file);
} else {
unsigned char *pt = buf;
do {
ch = st->stream_wgetc_for_read(sno);
if (ch < 127) {
if (ch < 0) {
break;
}
*pt++ = ch;
} else {
pt += get_utf8(pt, 4, &ch);
if (pt + 4 == buf + buf_sz)
break;
}
} while (ch != '\n');
sz = pt - buf;
}
if (do_as_binary && !binary_stream)
GLOBAL_Stream[sno].status &= ~Binary_Stream_f;
if (sz == -1 || sz == 0) {
if (GLOBAL_Stream[sno].status & Eof_Stream_f) {
UNLOCK(GLOBAL_Stream[sno].streamlock);
return Yap_unify_constant(ARG2, MkAtomTerm(AtomEof));
}
UNLOCK(GLOBAL_Stream[sno].streamlock);
}
if (GLOBAL_Stream[sno].status & Eof_Stream_f || buf[sz - 1] == 10) {
/* we're done */
Term end;
if (!(do_as_binary || GLOBAL_Stream[sno].status & Eof_Stream_f)) {
UNLOCK(GLOBAL_Stream[sno].streamlock);
/* handle CR before NL */
if ((Int)sz - 2 >= 0 && buf[sz - 2] == 13)
buf[sz - 2] = '\0';
else
buf[sz - 1] = '\0';
} else {
UNLOCK(GLOBAL_Stream[sno].streamlock);
}
if (arity == 2)
end = TermNil;
else
end = Deref(XREGS[arity]);
return Yap_unify(
ARG2, Yap_UTF8ToDiffListOfCodes((const char *)TR, end PASS_REGS));
}
buf += (buf_sz - 1);
max_inp -= (buf_sz - 1);
if (max_inp <= 0) {
UNLOCK(GLOBAL_Stream[sno].streamlock);
PlIOError(RESOURCE_ERROR_STACK, ARG1, "read_line_to_codes/%d", arity);
return FALSE;
}
}
}
static Int read_line_to_codes(USES_REGS1) {
return rl_to_codes(TermNil, FALSE, 2 PASS_REGS);
}
static Int read_line_to_codes2(USES_REGS1) {
return rl_to_codes(TermNil, TRUE, 3 PASS_REGS);
}
static Int read_line_to_string(USES_REGS1) {
int sno = Yap_CheckStream(ARG1, Input_Stream_f, "read_line_to_codes/2");
Int status;
UInt max_inp, buf_sz;
unsigned char *buf;
size_t sz;
StreamDesc *st = GLOBAL_Stream + sno;
int ch;
if (sno < 0)
return false;
status = GLOBAL_Stream[sno].status;
if (status & Eof_Stream_f) {
UNLOCK(GLOBAL_Stream[sno].streamlock);
return Yap_unify_constant(ARG2, MkAtomTerm(AtomEof));
}
max_inp = (ASP - HR) / 2 - 1024;
buf = (unsigned char *)TR;
buf_sz = (unsigned char *)LOCAL_TrailTop - buf;
if (buf_sz > max_inp) {
buf_sz = max_inp;
}
if (st->status & Binary_Stream_f) {
char *b = (char *)TR;
sz = fread(b, 1, buf_sz, GLOBAL_Stream[sno].file);
} else {
unsigned char *pt = buf;
do {
ch = st->stream_wgetc_for_read(sno);
if (ch < 127) {
if (ch < 0) {
break;
}
*pt++ = ch;
} else {
pt += get_utf8(pt, 4, &ch);
if (pt + 4 == buf + buf_sz)
break;
}
} while (ch != '\n');
sz = pt - buf;
}
if (sz == -1 || sz == 0) {
if (GLOBAL_Stream[sno].status & Eof_Stream_f) {
UNLOCK(GLOBAL_Stream[sno].streamlock);
return Yap_unify_constant(ARG2, MkAtomTerm(AtomEof));
}
UNLOCK(GLOBAL_Stream[sno].streamlock);
return false;
}
if (GLOBAL_Stream[sno].status & Eof_Stream_f || buf[sz - 1] == 10) {
/* we're done */
if (!(GLOBAL_Stream[sno].status & Eof_Stream_f)) {
UNLOCK(GLOBAL_Stream[sno].streamlock);
/* handle CR before NL */
if ((Int)sz - 2 >= 0 && buf[sz - 2] == 13)
buf[sz - 2] = '\0';
else {
buf[sz - 1] = '\0';
}
} else {
UNLOCK(GLOBAL_Stream[sno].streamlock);
}
}
if (GLOBAL_Stream[sno].encoding == ENC_ISO_UTF8) {
return Yap_unify(ARG2, Yap_UTF8ToString((const char *)TR PASS_REGS));
} else if (GLOBAL_Stream[sno].encoding == ENC_WCHAR) {
return Yap_unify(ARG2, Yap_WCharsToString((const wchar_t *)TR PASS_REGS));
} else {
return Yap_unify(
ARG2, Yap_CharsToString((const char *)TR, ENC_ISO_LATIN1 PASS_REGS));
}
buf += (buf_sz - 1);
max_inp -= (buf_sz - 1);
if (max_inp <= 0) {
UNLOCK(GLOBAL_Stream[sno].streamlock);
Yap_Error(RESOURCE_ERROR_STACK, ARG1, NULL);
return FALSE;
}
}
static Int read_stream_to_codes(USES_REGS1) {
int sno = Yap_CheckStream(ARG1, Input_Stream_f,
"reaMkAtomTerm (AtomEofd_line_to_codes/2");
CELL *HBASE = HR;
CELL *h0 = &ARG4;
if (sno < 0)
return FALSE;
while (!(GLOBAL_Stream[sno].status & Eof_Stream_f)) {
/* skip errors */
Int ch = GLOBAL_Stream[sno].stream_getc(sno);
Term t;
if (ch == EOFCHAR)
break;
t = MkIntegerTerm(ch);
h0[0] = AbsPair(HR);
*HR = t;
HR += 2;
h0 = HR - 1;
yhandle_t news, news1, st = Yap_StartSlots();
if (HR >= ASP - 1024) {
RESET_VARIABLE(h0);
news = Yap_InitSlot(AbsPair(HBASE));
news1 = Yap_InitSlot((CELL)(h0));
if (!Yap_gcl((ASP - HBASE) * sizeof(CELL), 3, ENV, Yap_gcP())) {
Yap_Error(RESOURCE_ERROR_STACK, ARG1, "read_stream_to_codes/3");
return false;
}
/* build a legal term again */
h0 = (CELL *)(Yap_GetFromSlot(news1));
HBASE = RepPair(Yap_GetFromSlot(news));
}
Yap_CloseSlots(st);
}
UNLOCK(GLOBAL_Stream[sno].streamlock);
if (HR == HBASE)
return Yap_unify(ARG2, ARG3);
RESET_VARIABLE(HR - 1);
Yap_unify(HR[-1], ARG3);
return Yap_unify(AbsPair(HBASE), ARG2);
}
static Int read_stream_to_terms(USES_REGS1) {
int sno = Yap_CheckStream(ARG1, Input_Stream_f, "read_line_to_codes/2");
Term t, hd;
yhandle_t tails, news;
if (sno < 0)
return FALSE;
t = AbsPair(HR);
RESET_VARIABLE(HR);
Yap_InitSlot((CELL)(HR));
tails = Yap_InitSlot((CELL)(HR));
news = Yap_InitSlot((CELL)(HR));
HR++;
while (!(GLOBAL_Stream[sno].status & Eof_Stream_f)) {
RESET_VARIABLE(HR);
RESET_VARIABLE(HR + 1);
hd = (CELL)HR;
Yap_PutInSlot(news, (CELL)(HR + 1));
HR += 2;
while ((hd = Yap_read_term(sno, TermNil, 2)) == 0L)
;
// just ignore failure
CELL *pt = VarOfTerm(Yap_GetFromSlot(tails));
if (Deref(hd) == TermEOfCode) {
*pt = Deref(ARG3);
break;
} else {
CELL *newpt = (CELL *)Yap_GetFromSlot(news);
*pt = AbsPair(newpt - 1);
Yap_PutInSlot(tails, (CELL)newpt);
}
}
UNLOCK(GLOBAL_Stream[sno].streamlock);
return Yap_unify(t, ARG2);
}
void Yap_InitReadUtil(void) {
CACHE_REGS
Term cm = CurrentModule;
CurrentModule = READUTIL_MODULE;
Yap_InitCPred("read_line_to_string", 2, read_line_to_string, SyncPredFlag);
Yap_InitCPred("read_line_to_codes", 2, read_line_to_codes, SyncPredFlag);
Yap_InitCPred("read_line_to_codes", 3, read_line_to_codes2, SyncPredFlag);
Yap_InitCPred("read_stream_to_codes", 3, read_stream_to_codes, SyncPredFlag);
Yap_InitCPred("read_stream_to_terms", 3, read_stream_to_terms, SyncPredFlag);
CurrentModule = cm;
}