1 /*
2  * gloc.c - gloc implementation
3  *
4  *   Copyright (c) 2000-2020  Shiro Kawai  <shiro@acm.org>
5  *
6  *   Redistribution and use in source and binary forms, with or without
7  *   modification, are permitted provided that the following conditions
8  *   are met:
9  *
10  *   1. Redistributions of source code must retain the above copyright
11  *      notice, this list of conditions and the following disclaimer.
12  *
13  *   2. Redistributions in binary form must reproduce the above copyright
14  *      notice, this list of conditions and the following disclaimer in the
15  *      documentation and/or other materials provided with the distribution.
16  *
17  *   3. Neither the name of the authors nor the names of its contributors
18  *      may be used to endorse or promote products derived from this
19  *      software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
27  *   TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
28  *   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
29  *   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30  *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
31  *   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #define LIBGAUCHE_BODY
35 #include "gauche.h"
36 
37 /*---------------------------------------------------------------
38  * GLOCs
39  */
40 
gloc_print(ScmObj obj,ScmPort * port,ScmWriteContext * ctx SCM_UNUSED)41 static void gloc_print(ScmObj obj, ScmPort *port,
42                        ScmWriteContext *ctx SCM_UNUSED)
43 {
44     ScmGloc *g = SCM_GLOC(obj);
45     Scm_Printf(port, "#<gloc %S#%S%s>", g->module->name,
46                g->name,
47                (Scm_GlocConstP(g)
48                 ? " const"
49                 : (Scm_GlocInlinableP(g)
50                    ? " inlinable"
51                    : (SCM_GLOC_PHANTOM_BINDING_P(g)
52                       ? " phantom"
53                       : ""))));
54 }
55 
56 SCM_DEFINE_BUILTIN_CLASS_SIMPLE(Scm_GlocClass, gloc_print);
57 
Scm_MakeGloc(ScmSymbol * sym,ScmModule * module)58 ScmObj Scm_MakeGloc(ScmSymbol *sym, ScmModule *module)
59 {
60     ScmGloc *g = SCM_NEW(ScmGloc);
61     SCM_SET_CLASS(g, &Scm_GlocClass);
62     g->name = sym;
63     g->module = module;
64     g->value = SCM_UNBOUND;
65     g->hidden = FALSE;
66     g->getter = NULL;
67     g->setter = NULL;
68     return SCM_OBJ(g);
69 }
70 
71 /* special setters for const and inlinable bindings. */
Scm_GlocConstSetter(ScmGloc * gloc,ScmObj val SCM_UNUSED)72 ScmObj Scm_GlocConstSetter(ScmGloc *gloc, ScmObj val SCM_UNUSED)
73 {
74     Scm_Error("cannot change constant value of %S#%S",
75               gloc->module->name, gloc->name);
76     return SCM_UNDEFINED;       /* dummy */
77 }
78 
Scm_GlocInlinableSetter(ScmGloc * gloc,ScmObj val)79 ScmObj Scm_GlocInlinableSetter(ScmGloc *gloc, ScmObj val)
80 {
81     Scm_Warn("altering binding of inlinable procedure: %S#%S",
82              gloc->module->name, gloc->name);
83     return val;
84 }
85 
Scm_GlocConstP(ScmGloc * gloc)86 int Scm_GlocConstP(ScmGloc *gloc)
87 {
88     return ((gloc)->setter == Scm_GlocConstSetter);
89 }
90 
Scm_GlocInlinableP(ScmGloc * gloc)91 int Scm_GlocInlinableP(ScmGloc *gloc)
92 {
93     return ((gloc)->setter == Scm_GlocInlinableSetter);
94 }
95 
96 /* Change binding flags.  Do not use casually. */
Scm_GlocMark(ScmGloc * gloc,int flags)97 void Scm_GlocMark(ScmGloc *gloc, int flags)
98 {
99     if (flags & SCM_BINDING_CONST) {
100         gloc->setter = Scm_GlocConstSetter;
101     } else if (flags & SCM_BINDING_INLINABLE) {
102         gloc->setter = Scm_GlocInlinableSetter;
103     } else {
104         gloc->setter = NULL;
105     }
106 }
107 
108 /* For the backward ABI compatibility */
Scm_GlocMarkConst(ScmGloc * gloc)109 ScmObj Scm_GlocMarkConst(ScmGloc *gloc)
110 {
111     Scm_GlocMark(gloc, SCM_BINDING_CONST);
112     return SCM_OBJ(gloc);
113 }
114 
115 /* For the backward ABI compatibility */
Scm_GlocUnmarkConst(ScmGloc * gloc)116 ScmObj Scm_GlocUnmarkConst(ScmGloc *gloc)
117 {
118     Scm_GlocMark(gloc, 0);
119     return SCM_OBJ(gloc);
120 }
121 
122