remove YAP memory (string) streams.

packages/PLStream/pl-file.c

@@ -4723,6 +4723,7 @@ init_yap(void)
   PL_register_extensions(PL_predicates_from_files);
   PL_register_extensions(PL_predicates_from_glob);
   PL_register_extensions(PL_predicates_from_write);
+  PL_register_extensions(PL_predicates_from_read);
   PL_register_extensions(foreigns);
   fileerrors = TRUE;
   SinitStreams();

packages/PLStream/pl-incl.h

@@ -1104,4 +1104,5 @@ extern const PL_extension PL_predicates_from_file[];
 extern const PL_extension PL_predicates_from_files[];
 extern const PL_extension PL_predicates_from_glob[];
 extern const PL_extension PL_predicates_from_write[];
+extern const PL_extension PL_predicates_from_read[];
 

packages/PLStream/pl-read.c

@@ -0,0 +1,134 @@
+
+#include "pl-incl.h"
+
+typedef struct
+{
+  term_t	varnames;		/* Report variables+names */  
+  IOSTREAM *stream;
+  int		has_exception;		/* exception is raised */
+
+  term_t	exception;		/* raised exception */
+} read_data, *ReadData;
+
+static void
+init_read_data(ReadData _PL_rd, IOSTREAM *in ARG_LD)
+{ 
+  _PL_rd->varnames = 0;
+  _PL_rd->stream = in;
+}
+
+static void
+free_read_data(ReadData _PL_rd)
+{ 
+}
+
+static int 
+read_term(term_t t, ReadData rd ARG_LD)
+{
+  return Yap_read_term(t, rd->stream, rd->varnames);
+}
+
+
+		 /*******************************
+		 *	   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

packages/PLStream/pl-yap.h

@@ -29,8 +29,9 @@ typedef YAP_Term	       *Word;		/* Anonymous 4 byte object */
 typedef YAP_Atom		Atom;
 typedef YAP_Term		(*Func)(term_t);	/* foreign functions */
 
-const char *Yap_GetCurrentPredName(void);
-YAP_Int     Yap_GetCurrentPredArity(void);
+extern const char *Yap_GetCurrentPredName(void);
+extern YAP_Int     Yap_GetCurrentPredArity(void);
+extern int Yap_read_term(term_t t, IOSTREAM *st, term_t *vs);
 
 
 extern atom_t codeToAtom(int chrcode);