static foreign_t
turtle_read_relative_uri(term_t C0, term_t Stream, term_t C, term_t Value)
{ int c;
charbuf b;
IOSTREAM *in;
if ( !PL_get_integer(C0, &c) )
return type_error(C0, "code");
if ( c != '<' )
return FALSE;
if ( !PL_get_stream_handle(Stream, &in) )
return FALSE;
init_charbuf(&b);
c = Sgetcode(in);
for(; ; c = Sgetcode(in))
{ if ( c == '>' )
{ int rc;
c = Sgetcode(in);
rc = (PL_unify_integer(C, c) &&
PL_unify_wchars(Value, PL_ATOM, b.here-b.base, b.base));
PL_release_stream(in);
free_charbuf(&b);
return rc;
} else if ( c == '\\' )
{ int esc;
c = Sgetcode(in);
if ( c == '>' )
{ add_charbuf(&b, c);
} else if ( string_escape(in, c, &esc) )
{ add_charbuf(&b, esc);
} else
{ free_charbuf(&b);
PL_release_stream(in);
return FALSE;
}
} else if ( c == -1 )
{ free_charbuf(&b);
PL_release_stream(in);
return syntax_error("eof_in_uri", in);
} else
{ add_charbuf(&b, c);
}
}
}
static foreign_t
turtle_read_name(term_t C0, term_t Stream, term_t C, term_t Name)
{ int c;
charbuf b;
IOSTREAM *in;
if ( !PL_get_integer(C0, &c) )
return type_error(C0, "code");
if ( !wcis_name_start_char(c) )
return FALSE;
if ( !PL_get_stream_handle(Stream, &in) )
return FALSE;
init_charbuf(&b);
add_charbuf(&b, c);
for(;;)
{ int c = Sgetcode(in);
if ( wcis_name_char(c) )
{ add_charbuf(&b, c);
} else
{ int rc = ( PL_unify_integer(C, c) &&
PL_unify_wchars(Name, PL_ATOM, b.here-b.base, b.base) );
free_charbuf(&b);
PL_release_stream(in);
return rc;
}
}
}
static int
read_hN(IOSTREAM *in, int digits, int *value)
{ int d = digits;
int v = 0;
while ( d-- > 0 )
{ int c = Sgetcode(in);
if ( c >= '0' && c <= '9' )
v = (v<<4) + c - '0';
else if ( c >= 'A' && c <= 'F' )
v = (v<<4) + c + 10 - 'A';
else if ( c >= 'a' && c <= 'f' )
v = (v<<4) + c + 10 - 'a';
else
{ if ( digits == 4 )
return syntax_error("Illegal \\uNNNN in string", in);
else
return syntax_error("Illegal \\UNNNNNNNN in string", in);
}
}
*value = v;
return TRUE;
}
static int
syntax_error(IOSTREAM *in, const char *msg)
{ term_t ex = PL_new_term_refs(2);
IOPOS *pos;
if ( !PL_unify_term(ex+0, PL_FUNCTOR, FUNCTOR_syntax_error1,
PL_CHARS, msg) )
return FALSE;
if ( (pos=in->position) )
{ term_t stream;
if ( !(stream = PL_new_term_ref()) ||
!PL_unify_stream(stream, in) ||
!PL_unify_term(ex+1,
PL_FUNCTOR, FUNCTOR_stream4,
PL_TERM, stream,
PL_INT, (int)pos->lineno,
PL_INT, (int)(pos->linepos-1), /* one too late */
PL_INT64, (int64_t)(pos->charno-1)) )
return FALSE;
}
if ( PL_cons_functor_v(ex, FUNCTOR_error2, ex) )
{ int c;
do
{ c = Sgetcode(in);
} while(c != '\n' && c != -1);
return PL_raise_exception(ex);
}
return FALSE;
}
static foreign_t
turtle_read_string(term_t C0, term_t Stream, term_t C, term_t Value)
{ int c;
charbuf b;
IOSTREAM *in;
int endlen = 1;
if ( !PL_get_integer(C0, &c) )
return type_error(C0, "code");
if ( c != '"' )
return FALSE;
if ( !PL_get_stream_handle(Stream, &in) )
return FALSE;
init_charbuf(&b);
c = Sgetcode(in);
if ( c == '"' )
{ c = Sgetcode(in);
if ( c == '"' ) /* """...""" */
{ endlen = 3;
c = Sgetcode(in);
} else
{ PL_release_stream(in);
return (PL_unify_integer(C, c) &&
PL_unify_atom(Value, ATOM_));
}
}
for(;;c = Sgetcode(in))
{ if ( c == -1 )
{ free_charbuf(&b);
PL_release_stream(in);
return syntax_error("eof_in_string", in);
} else if ( c == '"' )
{ int count = 1;
for(count=1; count<endlen; )
{ if ( (c=Sgetcode(in)) == '"' )
count++;
else
break;
}
if ( count == endlen )
{ int rc;
c = Sgetcode(in);
rc = (PL_unify_integer(C, c) &&
PL_unify_wchars(Value, PL_ATOM, b.here-b.base, b.base));
free_charbuf(&b);
PL_release_stream(in);
return rc;
}
while(count-- > 0)
add_charbuf(&b, '"');
add_charbuf(&b, c);
} else if ( c == '\\' )
{ int esc;
c = Sgetcode(in);
if ( !string_escape(in, c, &esc) )
{ free_charbuf(&b);
PL_release_stream(in);
return FALSE;
}
add_charbuf(&b, esc);
} else
{ add_charbuf(&b, c);
}
}
}
