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yap-6.3/packages/PLStream/pl-read.c

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2011-02-12 18:42:44 +00:00
#include "pl-incl.h"
#include "pl-ctype.h"
#include "pl-utf8.h"
#include "pl-dtoa.h"
#include "pl-umap.c" /* Unicode map */
typedef unsigned char * ucharp;
typedef const unsigned char * cucharp;
#define utf8_get_uchar(s, chr) (ucharp)utf8_get_char((char *)(s), chr)
#define FASTBUFFERSIZE 256 /* read quickly upto this size */
struct read_buffer
{ int size; /* current size of read buffer */
unsigned char *base; /* base of read buffer */
unsigned char *here; /* current position in read buffer */
unsigned char *end; /* end of the valid buffer */
IOSTREAM *stream; /* stream we are reading from */
unsigned char fast[FASTBUFFERSIZE]; /* Quick internal buffer */
};
2011-02-12 18:42:44 +00:00
typedef struct
{ unsigned char *here; /* current character */
unsigned char *base; /* base of clause */
unsigned char *end; /* end of the clause */
unsigned char *token_start; /* start of most recent read token */
2011-02-12 18:42:44 +00:00
int has_exception; /* exception is raised */
unsigned char *posp; /* position pointer */
size_t posi; /* position number */
unsigned int flags; /* Module syntax flags */
int styleCheck; /* style-checking mask */
bool backquoted_string; /* Read `hello` as string */
2011-02-23 17:46:50 +00:00
int *char_conversion_table; /* active conversion table */
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term_t exception; /* raised exception */
term_t varnames; /* Report variables+names */
int strictness; /* Strictness level */
term_t comments; /* Report comments */
struct read_buffer _rb; /* keep read characters here */
2011-02-12 18:42:44 +00:00
} read_data, *ReadData;
#define rdhere (_PL_rd->here)
#define rdbase (_PL_rd->base)
#define rdend (_PL_rd->end)
#define last_token_start (_PL_rd->token_start)
#define rb (_PL_rd->_rb)
#define DO_CHARESCAPE true(_PL_rd, CHARESCAPE)
extern IOFUNCTIONS Sstringfunctions;
static bool
isStringStream(IOSTREAM *s)
{ return s->functions == &Sstringfunctions;
}
2011-02-12 18:42:44 +00:00
static void
init_read_data(ReadData _PL_rd, IOSTREAM *in ARG_LD)
{ memset(_PL_rd, 0, sizeof(*_PL_rd)); /* optimise! */
2011-02-12 18:42:44 +00:00
_PL_rd->varnames = 0;
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rb.stream = in;
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_PL_rd->has_exception = 0;
_PL_rd->exception = 0;
2011-02-12 18:42:44 +00:00
}
static void
free_read_data(ReadData _PL_rd)
{
}
static int
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read_term(term_t t, ReadData _PL_rd ARG_LD)
2011-02-12 18:42:44 +00:00
{
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int rval;
term_t except;
if (!(rval = Yap_read_term(t, rb.stream, &except, _PL_rd->varnames))) {
if (except) {
_PL_rd->has_exception = TRUE;
_PL_rd->exception = except;
}
}
return rval;
2011-02-12 18:42:44 +00:00
}
static void addUTF8Buffer(Buffer b, int c);
static void
addUTF8Buffer(Buffer b, int c)
{ if ( c >= 0x80 )
{ char buf[6];
char *p, *end;
end = utf8_put_char(buf, c);
for(p=buf; p<end; p++)
{ addBuffer(b, *p&0xff, char);
}
} else
{ addBuffer(b, c, char);
}
}
/*******************************
* UNICODE CLASSIFIERS *
*******************************/
#define CharTypeW(c, t, w) \
((unsigned)(c) <= 0xff ? (_PL_char_types[(unsigned)(c)] t) \
: (uflagsW(c) & w))
#define PlBlankW(c) CharTypeW(c, <= SP, U_SEPARATOR)
#define PlUpperW(c) CharTypeW(c, == UC, U_UPPERCASE)
#define PlIdStartW(c) (c <= 0xff ? (isLower(c)||isUpper(c)||c=='_') \
: uflagsW(c) & U_ID_START)
#define PlIdContW(c) CharTypeW(c, >= UC, U_ID_CONTINUE)
#define PlSymbolW(c) CharTypeW(c, == SY, 0)
#define PlPunctW(c) CharTypeW(c, == PU, 0)
#define PlSoloW(c) CharTypeW(c, == SO, 0)
int
unicode_separator(pl_wchar_t c)
{ return PlBlankW(c);
}
/********************************
* RAW READING *
*********************************/
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Scan the input, give prompts when necessary and return a char * holding
a stripped version of the next term. Contiguous white space is mapped
on a single space, block and % ... \n comment is deleted. Memory is
claimed automatically en enlarged if necessary.
(char *) NULL is returned on a syntax error.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
#define syntaxError(what, rd) { errorWarning(what, 0, rd); fail; }
static term_t
makeErrorTerm(const char *id_str, term_t id_term, ReadData _PL_rd)
{ GET_LD
term_t ex, loc=0; /* keep compiler happy */
unsigned char const *s, *ll = NULL;
int rc = TRUE;
if ( !(ex = PL_new_term_ref()) ||
!(loc = PL_new_term_ref()) )
rc = FALSE;
if ( rc && !id_term )
{ if ( !(id_term=PL_new_term_ref()) ||
!PL_put_atom_chars(id_term, id_str) )
rc = FALSE;
}
if ( rc )
rc = PL_unify_term(ex,
PL_FUNCTOR, FUNCTOR_error2,
PL_FUNCTOR, FUNCTOR_syntax_error1,
PL_TERM, id_term,
PL_TERM, loc);
source_char_no += last_token_start - rdbase;
for(s=rdbase; s<last_token_start; s++)
{ if ( *s == '\n' )
{ source_line_no++;
ll = s+1;
}
}
if ( ll )
{ int lp = 0;
for(s = ll; s<last_token_start; s++)
{ switch(*s)
{ case '\b':
if ( lp > 0 ) lp--;
break;
case '\t':
lp |= 7;
default:
lp++;
}
}
source_line_pos = lp;
}
if ( rc )
{ if ( ReadingSource ) /* reading a file */
{ rc = PL_unify_term(loc,
PL_FUNCTOR, FUNCTOR_file4,
PL_ATOM, source_file_name,
PL_INT, source_line_no,
PL_INT, source_line_pos,
PL_INT64, source_char_no);
} else if ( isStringStream(rb.stream) )
{ size_t pos;
pos = utf8_strlen((char *)rdbase, last_token_start-rdbase);
rc = PL_unify_term(loc,
PL_FUNCTOR, FUNCTOR_string2,
PL_UTF8_STRING, rdbase,
PL_INT, (int)pos);
} else /* any stream */
{ term_t stream;
if ( !(stream=PL_new_term_ref()) ||
!PL_unify_stream_or_alias(stream, rb.stream) ||
!PL_unify_term(loc,
PL_FUNCTOR, FUNCTOR_stream4,
PL_TERM, stream,
PL_INT, source_line_no,
PL_INT, source_line_pos,
PL_INT64, source_char_no) )
rc = FALSE;
}
}
return (rc ? ex : (term_t)0);
}
static bool
errorWarning(const char *id_str, term_t id_term, ReadData _PL_rd)
{ GET_LD
term_t ex;
LD->exception.processing = TRUE; /* allow using spare stack */
ex = makeErrorTerm(id_str, id_term, _PL_rd);
if ( _PL_rd )
{ _PL_rd->has_exception = TRUE;
if ( ex )
PL_put_term(_PL_rd->exception, ex);
else
PL_put_term(_PL_rd->exception, exception_term);
} else
{ if ( ex )
PL_raise_exception(ex);
}
fail;
}
static void
clearBuffer(ReadData _PL_rd)
{ if (rb.size == 0)
{ rb.base = rb.fast;
rb.size = sizeof(rb.fast);
}
rb.end = rb.base + rb.size;
rdbase = rb.here = rb.base;
_PL_rd->posp = rdbase;
_PL_rd->posi = 0;
}
static void
growToBuffer(int c, ReadData _PL_rd)
{ if ( rb.base == rb.fast ) /* intptr_t clause: jump to use malloc() */
{ rb.base = PL_malloc(FASTBUFFERSIZE * 2);
memcpy(rb.base, rb.fast, FASTBUFFERSIZE);
} else
rb.base = PL_realloc(rb.base, rb.size*2);
DEBUG(8, Sdprintf("Reallocated read buffer at %ld\n", (intptr_t) rb.base));
_PL_rd->posp = rdbase = rb.base;
rb.here = rb.base + rb.size;
rb.size *= 2;
rb.end = rb.base + rb.size;
_PL_rd->posi = 0;
*rb.here++ = c;
}
static inline void
addByteToBuffer(int c, ReadData _PL_rd)
{ c &= 0xff;
if ( rb.here >= rb.end )
growToBuffer(c, _PL_rd);
else
*rb.here++ = c;
}
static void
addToBuffer(int c, ReadData _PL_rd)
{ if ( c <= 0x7f )
{ addByteToBuffer(c, _PL_rd);
} else
{ char buf[10];
char *s, *e;
e = utf8_put_char(buf, c);
for(s=buf; s<e; s++)
addByteToBuffer(*s, _PL_rd);
}
}
static void
setCurrentSourceLocation(IOSTREAM *s ARG_LD)
{ atom_t a;
if ( s->position )
{ source_line_no = s->position->lineno;
source_line_pos = s->position->linepos - 1; /* char just read! */
source_char_no = s->position->charno - 1; /* char just read! */
} else
{ source_line_no = -1;
source_line_pos = -1;
source_char_no = 0;
}
if ( (a = fileNameStream(s)) )
source_file_name = a;
else
source_file_name = NULL_ATOM;
}
2011-03-11 19:49:32 +00:00
#if __YAP_PROLOG__
void
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Yap_setCurrentSourceLocation(IOSTREAM **s)
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{
GET_LD
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if (!*s)
*s = Suser_input;
setCurrentSourceLocation(*s PASS_LD);
2011-03-11 19:49:32 +00:00
}
#endif
static inline int
getchr__(ReadData _PL_rd)
{ int c = Sgetcode(rb.stream);
if ( !_PL_rd->char_conversion_table || c < 0 || c >= 256 )
return c;
return _PL_rd->char_conversion_table[c];
}
#define getchr() getchr__(_PL_rd)
#define getchrq() Sgetcode(rb.stream)
#define ensure_space(c) { if ( something_read && \
(c == '\n' || !isBlank(rb.here[-1])) ) \
addToBuffer(c, _PL_rd); \
}
#define set_start_line { if ( !something_read ) \
{ setCurrentSourceLocation(rb.stream PASS_LD); \
something_read++; \
} \
}
#define rawSyntaxError(what) { addToBuffer(EOS, _PL_rd); \
rdbase = rb.base, last_token_start = rb.here-1; \
syntaxError(what, _PL_rd); \
}
static int
raw_read_quoted(int q, ReadData _PL_rd)
{ int newlines = 0;
int c;
addToBuffer(q, _PL_rd);
while((c=getchrq()) != EOF && c != q)
{ if ( c == '\\' && DO_CHARESCAPE )
{ int base;
addToBuffer(c, _PL_rd);
switch( (c=getchrq()) )
{ case EOF:
goto eofinstr;
case 'u': /* \uXXXX */
case 'U': /* \UXXXXXXXX */
addToBuffer(c, _PL_rd);
continue;
case 'x': /* \xNN\ */
addToBuffer(c, _PL_rd);
c = getchrq();
if ( c == EOF )
goto eofinstr;
if ( digitValue(16, c) >= 0 )
{ base = 16;
addToBuffer(c, _PL_rd);
xdigits:
c = getchrq();
while( digitValue(base, c) >= 0 )
{ addToBuffer(c, _PL_rd);
c = getchrq();
}
}
if ( c == EOF )
goto eofinstr;
addToBuffer(c, _PL_rd);
if ( c == q )
return TRUE;
continue;
default:
addToBuffer(c, _PL_rd);
if ( digitValue(8, c) >= 0 ) /* \NNN\ */
{ base = 8;
goto xdigits;
} else if ( c == '\n' ) /* \<newline> */
{ c = getchrq();
if ( c == EOF )
goto eofinstr;
addToBuffer(c, _PL_rd);
if ( c == q )
return TRUE;
}
continue; /* \symbolic-control-char */
}
} else if (c == '\n' &&
newlines++ > MAXNEWLINES &&
(_PL_rd->styleCheck & LONGATOM_CHECK))
{ rawSyntaxError("long_string");
}
addToBuffer(c, _PL_rd);
}
if (c == EOF)
{ eofinstr:
rawSyntaxError("end_of_file_in_string");
}
addToBuffer(c, _PL_rd);
return TRUE;
}
static int
add_comment(Buffer b, IOPOS *pos, ReadData _PL_rd ARG_LD)
{ term_t head = PL_new_term_ref();
assert(_PL_rd->comments);
if ( !PL_unify_list(_PL_rd->comments, head, _PL_rd->comments) )
return FALSE;
if ( pos )
{ if ( !PL_unify_term(head,
PL_FUNCTOR, FUNCTOR_minus2,
PL_FUNCTOR, FUNCTOR_stream_position4,
PL_INT64, pos->charno,
PL_INT, pos->lineno,
PL_INT, pos->linepos,
PL_INT, 0,
PL_UTF8_STRING, baseBuffer(b, char)) )
return FALSE;
} else
{ if ( !PL_unify_term(head,
PL_FUNCTOR, FUNCTOR_minus2,
ATOM_minus,
PL_UTF8_STRING, baseBuffer(b, char)) )
return FALSE;
}
PL_reset_term_refs(head);
return TRUE;
}
static void
setErrorLocation(IOPOS *pos, ReadData _PL_rd)
{ if ( pos )
{ GET_LD
source_char_no = pos->charno;
source_line_pos = pos->linepos;
source_line_no = pos->lineno;
}
rb.here = rb.base+1; /* see rawSyntaxError() */
}
static unsigned char *
raw_read2(ReadData _PL_rd ARG_LD)
{ int c;
bool something_read = FALSE;
bool dotseen = FALSE;
IOPOS pbuf; /* comment start */
IOPOS *pos;
clearBuffer(_PL_rd); /* clear input buffer */
_PL_rd->strictness = truePrologFlag(PLFLAG_ISO);
source_line_no = -1;
for(;;)
{ c = getchr();
handle_c:
switch(c)
{ case EOF:
if ( isStringStream(rb.stream) ) /* do not require '. ' when */
{ addToBuffer(' ', _PL_rd); /* reading from a string */
addToBuffer('.', _PL_rd);
addToBuffer(' ', _PL_rd);
addToBuffer(EOS, _PL_rd);
return rb.base;
}
if (something_read)
{ if ( dotseen ) /* term.<EOF> */
{ if ( rb.here - rb.base == 1 )
rawSyntaxError("end_of_clause");
ensure_space(' ');
addToBuffer(EOS, _PL_rd);
return rb.base;
}
rawSyntaxError("end_of_file");
}
if ( Sfpasteof(rb.stream) )
{ term_t stream;
LD->exception.processing = TRUE;
stream = PL_new_term_ref();
PL_unify_stream_or_alias(stream, rb.stream);
PL_error(NULL, 0, NULL, ERR_PERMISSION,
ATOM_input, ATOM_past_end_of_stream, stream);
return NULL;
}
set_start_line;
strcpy((char *)rb.base, "end_of_file. ");
rb.here = rb.base + 14;
return rb.base;
case '/': if ( rb.stream->position )
{ pbuf = *rb.stream->position;
pbuf.charno--;
pbuf.linepos--;
pos = &pbuf;
} else
pos = NULL;
c = getchr();
if ( c == '*' )
{ int last;
int level = 1;
union {
tmp_buffer ctmpbuf;
buffer tmpbuf;
} u;
Buffer cbuf;
if ( _PL_rd->comments )
{ initBuffer(&u.ctmpbuf);
cbuf = &u.tmpbuf;
addUTF8Buffer(cbuf, '/');
addUTF8Buffer(cbuf, '*');
} else
{ cbuf = NULL;
}
if ((last = getchr()) == EOF)
{ if ( cbuf )
discardBuffer(cbuf);
setErrorLocation(pos, _PL_rd);
rawSyntaxError("end_of_file_in_block_comment");
}
if ( cbuf )
addUTF8Buffer(cbuf, last);
if ( something_read )
{ addToBuffer(' ', _PL_rd); /* positions */
addToBuffer(' ', _PL_rd);
addToBuffer(last == '\n' ? last : ' ', _PL_rd);
}
for(;;)
{ c = getchr();
if ( cbuf )
addUTF8Buffer(cbuf, c);
switch( c )
{ case EOF:
if ( cbuf )
discardBuffer(cbuf);
setErrorLocation(pos, _PL_rd);
rawSyntaxError("end_of_file_in_block_comment");
case '*':
if ( last == '/' )
level++;
break;
case '/':
if ( last == '*' &&
(--level == 0 || _PL_rd->strictness) )
{ if ( cbuf )
{ addUTF8Buffer(cbuf, EOS);
if ( !add_comment(cbuf, pos, _PL_rd PASS_LD) )
{ discardBuffer(cbuf);
return FALSE;
}
discardBuffer(cbuf);
}
c = ' ';
goto handle_c;
}
break;
}
if ( something_read )
addToBuffer(c == '\n' ? c : ' ', _PL_rd);
last = c;
}
} else
{ set_start_line;
addToBuffer('/', _PL_rd);
if ( isSymbolW(c) )
{ while( c != EOF && isSymbolW(c) &&
!(c == '`' && _PL_rd->backquoted_string) )
{ addToBuffer(c, _PL_rd);
c = getchr();
}
}
dotseen = FALSE;
goto handle_c;
}
case '%': if ( something_read )
addToBuffer(' ', _PL_rd);
if ( _PL_rd->comments )
{ union {
tmp_buffer ctmpbuf;
buffer uctmpbuf;
} u;
Buffer cbuf;
if ( rb.stream->position )
{ pbuf = *rb.stream->position;
pbuf.charno--;
pbuf.linepos--;
pos = &pbuf;
} else
pos = NULL;
initBuffer(&u.ctmpbuf);
cbuf = (Buffer)&u.uctmpbuf;
addUTF8Buffer(cbuf, '%');
for(;;)
{ while((c=getchr()) != EOF && c != '\n')
{ addUTF8Buffer(cbuf, c);
if ( something_read ) /* record positions */
addToBuffer(' ', _PL_rd);
}
if ( c == '\n' )
{ int c2 = Speekcode(rb.stream);
if ( c2 == '%' )
{ if ( something_read )
{ addToBuffer(c, _PL_rd);
addToBuffer(' ', _PL_rd);
}
addUTF8Buffer(cbuf, c);
c = Sgetcode(rb.stream);
assert(c==c2);
addUTF8Buffer(cbuf, c);
continue;
}
}
break;
}
addUTF8Buffer(cbuf, EOS);
if ( !add_comment(cbuf, pos, _PL_rd PASS_LD) )
{ discardBuffer(cbuf);
return FALSE;
}
discardBuffer(cbuf);
} else
{ while((c=getchr()) != EOF && c != '\n')
{ if ( something_read ) /* record positions */
addToBuffer(' ', _PL_rd);
}
}
goto handle_c; /* is the newline */
case '\'': if ( rb.here > rb.base && isDigit(rb.here[-1]) )
{ cucharp bs = &rb.here[-1];
if ( bs > rb.base && isDigit(bs[-1]) )
bs--;
if ( bs > rb.base && isSign(bs[-1]) )
bs--;
if ( bs == rb.base || !PlIdContW(bs[-1]) )
{ int base;
if ( isSign(bs[0]) )
bs++;
base = atoi((char*)bs);
if ( base <= 36 )
{ if ( base == 0 ) /* 0'<c> */
{ addToBuffer(c, _PL_rd);
{ if ( (c=getchr()) != EOF )
{ addToBuffer(c, _PL_rd);
if ( c == '\\' ) /* 0'\<c> */
{ if ( (c=getchr()) != EOF )
addToBuffer(c, _PL_rd);
} else if ( c == '\'' ) /* 0'' */
{ if ( (c=getchr()) != EOF )
{ if ( c == '\'' )
addToBuffer(c, _PL_rd);
else
goto handle_c;
}
}
break;
}
rawSyntaxError("end_of_file");
}
} else
{ int c2 = Speekcode(rb.stream);
if ( c2 != EOF )
{ if ( digitValue(base, c2) >= 0 )
{ addToBuffer(c, _PL_rd);
c = Sgetcode(rb.stream);
addToBuffer(c, _PL_rd);
dotseen = FALSE;
break;
}
goto sqatom;
}
rawSyntaxError("end_of_file");
}
}
}
}
sqatom:
set_start_line;
if ( !raw_read_quoted(c, _PL_rd) )
fail;
dotseen = FALSE;
break;
case '"': set_start_line;
if ( !raw_read_quoted(c, _PL_rd) )
fail;
dotseen = FALSE;
break;
case '.': addToBuffer(c, _PL_rd);
set_start_line;
dotseen++;
c = getchr();
if ( isSymbolW(c) )
{ while( c != EOF && isSymbolW(c) &&
!(c == '`' && _PL_rd->backquoted_string) )
{ addToBuffer(c, _PL_rd);
c = getchr();
}
dotseen = FALSE;
}
goto handle_c;
case '`': if ( _PL_rd->backquoted_string )
{ set_start_line;
if ( !raw_read_quoted(c, _PL_rd) )
fail;
dotseen = FALSE;
break;
}
/*FALLTHROUGH*/
default: if ( c < 0xff )
{ switch(_PL_char_types[c])
{ case SP:
case CT:
blank:
if ( dotseen )
{ if ( rb.here - rb.base == 1 )
rawSyntaxError("end_of_clause");
ensure_space(c);
addToBuffer(EOS, _PL_rd);
return rb.base;
}
do
{ if ( something_read ) /* positions, \0 --> ' ' */
addToBuffer(c ? c : ' ', _PL_rd);
else
ensure_space(c);
c = getchr();
} while( c != EOF && PlBlankW(c) );
goto handle_c;
case SY:
set_start_line;
do
{ addToBuffer(c, _PL_rd);
c = getchr();
if ( c == '`' && _PL_rd->backquoted_string )
break;
} while( c != EOF && c <= 0xff && isSymbol(c) );
/* TBD: wide symbols? */
dotseen = FALSE;
goto handle_c;
case LC:
case UC:
set_start_line;
do
{ addToBuffer(c, _PL_rd);
c = getchr();
} while( c != EOF && PlIdContW(c) );
dotseen = FALSE;
goto handle_c;
default:
addToBuffer(c, _PL_rd);
dotseen = FALSE;
set_start_line;
}
} else /* > 255 */
{ if ( PlIdStartW(c) )
{ set_start_line;
do
{ addToBuffer(c, _PL_rd);
c = getchr();
} while( c != EOF && PlIdContW(c) );
dotseen = FALSE;
goto handle_c;
} else if ( PlBlankW(c) )
{ goto blank;
} else
{ addToBuffer(c, _PL_rd);
dotseen = FALSE;
set_start_line;
}
}
}
}
}
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Raw reading returns a string in UTF-8 notation of the a Prolog term.
Comment inside the term is replaced by spaces or newline to ensure
proper reconstruction of source locations. Comment before the term is
skipped.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
static unsigned char *
raw_read(ReadData _PL_rd, unsigned char **endp ARG_LD)
{ unsigned char *s;
if ( (rb.stream->flags & SIO_ISATTY) && Sfileno(rb.stream) >= 0 )
{ ttybuf tab;
PushTty(rb.stream, &tab, TTY_SAVE); /* make sure tty is sane */
PopTty(rb.stream, &ttytab, FALSE);
s = raw_read2(_PL_rd PASS_LD);
PopTty(rb.stream, &tab, TRUE);
} else
{ s = raw_read2(_PL_rd PASS_LD);
}
if ( endp )
*endp = _PL_rd->_rb.here;
return s;
}
/********************************
* PROLOG CONNECTION *
*********************************/
static unsigned char *
backSkipUTF8(unsigned const char *start, unsigned const char *end, int *chr)
{ const unsigned char *s;
for(s=end-1 ; s>start && *s&0x80; s--)
;
utf8_get_char((char*)s, chr);
return (unsigned char *)s;
}
static unsigned char *
backSkipBlanks(const unsigned char *start, const unsigned char *end)
{ const unsigned char *s;
for( ; end > start; end = s)
{ unsigned char *e;
int chr;
for(s=end-1 ; s>start && ISUTF8_CB(*s); s--)
;
e = (unsigned char*)utf8_get_char((char*)s, &chr);
assert(e == end);
if ( !PlBlankW(chr) )
return (unsigned char*)end;
}
return (unsigned char *)start;
}
static inline ucharp
skipSpaces(cucharp in)
{ int chr;
ucharp s;
for( ; *in; in=s)
{ s = utf8_get_uchar(in, &chr);
if ( !PlBlankW(chr) )
return (ucharp)in;
}
return (ucharp)in;
}
word
pl_raw_read2(term_t from, term_t term)
{ GET_LD
unsigned char *s, *e, *t2, *top;
read_data rd;
word rval;
IOSTREAM *in;
int chr;
PL_chars_t txt;
if ( !getInputStream(from, &in) )
fail;
init_read_data(&rd, in PASS_LD);
if ( !(s = raw_read(&rd, &e PASS_LD)) )
{ rval = PL_raise_exception(rd.exception);
goto out;
}
/* strip the input from blanks */
top = backSkipBlanks(s, e-1);
t2 = backSkipUTF8(s, top, &chr);
if ( chr == '.' )
top = backSkipBlanks(s, t2);
/* watch for "0' ." */
if ( top < e && top-2 >= s && top[-1] == '\'' && top[-2] == '0' )
top++;
*top = EOS;
s = skipSpaces(s);
txt.text.t = (char*)s;
txt.length = top-s;
txt.storage = PL_CHARS_HEAP;
txt.encoding = ENC_UTF8;
txt.canonical = FALSE;
rval = PL_unify_text(term, 0, &txt, PL_ATOM);
out:
free_read_data(&rd);
if ( Sferror(in) )
return streamStatus(in);
else
PL_release_stream(in);
return rval;
}
word
pl_raw_read(term_t term)
{ return pl_raw_read2(0, term);
}
2011-02-12 18:42:44 +00:00
/*******************************
* TERM <->ATOM *
*******************************/
static int
atom_to_term(term_t atom, term_t term, term_t bindings)
{ GET_LD
PL_chars_t txt;
if ( !bindings && PL_is_variable(atom) ) /* term_to_atom(+, -) */
{ char buf[1024];
size_t bufsize = sizeof(buf);
int rval;
char *s = buf;
IOSTREAM *stream;
PL_chars_t txt;
stream = Sopenmem(&s, &bufsize, "w");
stream->encoding = ENC_UTF8;
PL_write_term(stream, term, 1200, PL_WRT_QUOTED);
Sflush(stream);
txt.text.t = s;
txt.length = bufsize;
txt.storage = PL_CHARS_HEAP;
txt.encoding = ENC_UTF8;
txt.canonical = FALSE;
rval = PL_unify_text(atom, 0, &txt, PL_ATOM);
Sclose(stream);
if ( s != buf )
Sfree(s);
return rval;
}
if ( PL_get_text(atom, &txt, CVT_ALL|CVT_EXCEPTION) )
{ GET_LD
read_data rd;
int rval;
IOSTREAM *stream;
source_location oldsrc = LD->read_source;
stream = Sopen_text(&txt, "r");
init_read_data(&rd, stream PASS_LD);
if ( bindings && (PL_is_variable(bindings) || PL_is_list(bindings)) )
rd.varnames = bindings;
else if ( bindings )
return PL_error(NULL, 0, NULL, ERR_TYPE, ATOM_list, bindings);
if ( !(rval = read_term(term, &rd PASS_LD)) && rd.has_exception )
rval = PL_raise_exception(rd.exception);
free_read_data(&rd);
Sclose(stream);
LD->read_source = oldsrc;
return rval;
}
fail;
}
static
PRED_IMPL("atom_to_term", 3, atom_to_term, 0)
{ return atom_to_term(A1, A2, A3);
}
static
PRED_IMPL("term_to_atom", 2, term_to_atom, 0)
{ return atom_to_term(A2, A1, 0);
}
int
PL_chars_to_term(const char *s, term_t t)
{ GET_LD
read_data rd;
int rval;
IOSTREAM *stream = Sopen_string(NULL, (char *)s, -1, "r");
source_location oldsrc = LD->read_source;
init_read_data(&rd, stream PASS_LD);
PL_put_variable(t);
if ( !(rval = read_term(t, &rd PASS_LD)) && rd.has_exception )
PL_put_term(t, rd.exception);
free_read_data(&rd);
Sclose(stream);
LD->read_source = oldsrc;
return rval;
}
/*******************************
* PUBLISH PREDICATES *
*******************************/
BeginPredDefs(read)
PRED_DEF("atom_to_term", 3, atom_to_term, 0)
PRED_DEF("term_to_atom", 2, term_to_atom, 0)
EndPredDefs