Merge branch 'master' of ssh://git.gag.com/scm/git/fw/altos
[fw/altos] / src / scheme / ao_scheme_cons.c
1 /*
2  * Copyright © 2016 Keith Packard <keithp@keithp.com>
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation, either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12  * General Public License for more details.
13  */
14
15 #include "ao_scheme.h"
16
17 static void cons_mark(void *addr)
18 {
19         struct ao_scheme_cons   *cons = addr;
20
21         for (;;) {
22                 ao_poly cdr = cons->cdr;
23
24                 ao_scheme_poly_mark(cons->car, 1);
25                 if (!cdr)
26                         break;
27                 if (ao_scheme_poly_type(cdr) != AO_SCHEME_CONS) {
28                         ao_scheme_poly_mark(cdr, 1);
29                         break;
30                 }
31                 cons = ao_scheme_poly_cons(cdr);
32                 if (ao_scheme_mark_memory(&ao_scheme_cons_type, cons))
33                         break;
34         }
35 }
36
37 static int cons_size(void *addr)
38 {
39         (void) addr;
40         return sizeof (struct ao_scheme_cons);
41 }
42
43 static void cons_move(void *addr)
44 {
45         struct ao_scheme_cons   *cons = addr;
46
47         if (!cons)
48                 return;
49
50         for (;;) {
51                 ao_poly                 cdr;
52                 struct ao_scheme_cons   *c;
53                 int     ret;
54
55                 MDBG_MOVE("cons_move start %d (%d, %d)\n",
56                           MDBG_OFFSET(cons), MDBG_OFFSET(ao_scheme_ref(cons->car)), MDBG_OFFSET(ao_scheme_ref(cons->cdr)));
57                 (void) ao_scheme_poly_move(&cons->car, 1);
58                 cdr = cons->cdr;
59                 if (!cdr)
60                         break;
61                 if (ao_scheme_poly_base_type(cdr) != AO_SCHEME_CONS) {
62                         (void) ao_scheme_poly_move(&cons->cdr, 0);
63                         break;
64                 }
65                 c = ao_scheme_poly_cons(cdr);
66                 ret = ao_scheme_move_memory(&ao_scheme_cons_type, (void **) &c);
67                 if (c != ao_scheme_poly_cons(cons->cdr))
68                         cons->cdr = ao_scheme_cons_poly(c);
69                 MDBG_MOVE("cons_move end %d (%d, %d)\n",
70                           MDBG_OFFSET(cons), MDBG_OFFSET(ao_scheme_ref(cons->car)), MDBG_OFFSET(ao_scheme_ref(cons->cdr)));
71                 if (ret)
72                         break;
73                 cons = c;
74         }
75 }
76
77 const struct ao_scheme_type ao_scheme_cons_type = {
78         .mark = cons_mark,
79         .size = cons_size,
80         .move = cons_move,
81         .name = "cons",
82 };
83
84 struct ao_scheme_cons *ao_scheme_cons_free_list;
85
86 struct ao_scheme_cons *
87 ao_scheme_cons_cons(ao_poly car, ao_poly cdr)
88 {
89         struct ao_scheme_cons   *cons;
90
91         if (ao_scheme_cons_free_list) {
92                 cons = ao_scheme_cons_free_list;
93                 ao_scheme_cons_free_list = ao_scheme_poly_cons(cons->cdr);
94         } else {
95                 ao_scheme_poly_stash(0, car);
96                 ao_scheme_poly_stash(1, cdr);
97                 cons = ao_scheme_alloc(sizeof (struct ao_scheme_cons));
98                 cdr = ao_scheme_poly_fetch(1);
99                 car = ao_scheme_poly_fetch(0);
100                 if (!cons)
101                         return NULL;
102         }
103         cons->car = car;
104         cons->cdr = cdr;
105         return cons;
106 }
107
108 struct ao_scheme_cons *
109 ao_scheme_cons_cdr(struct ao_scheme_cons *cons)
110 {
111         ao_poly cdr = cons->cdr;
112         if (cdr == AO_SCHEME_NIL)
113                 return NULL;
114         if (ao_scheme_poly_type(cdr) != AO_SCHEME_CONS) {
115                 (void) ao_scheme_error(AO_SCHEME_INVALID, "improper list");
116                 return NULL;
117         }
118         return ao_scheme_poly_cons(cdr);
119 }
120
121 ao_poly
122 ao_scheme__cons(ao_poly car, ao_poly cdr)
123 {
124         return ao_scheme_cons_poly(ao_scheme_cons_cons(car, cdr));
125 }
126
127 void
128 ao_scheme_cons_free(struct ao_scheme_cons *cons)
129 {
130 #if DBG_FREE_CONS
131         ao_scheme_cons_check(cons);
132 #endif
133         while (cons) {
134                 ao_poly cdr = cons->cdr;
135                 cons->cdr = ao_scheme_cons_poly(ao_scheme_cons_free_list);
136                 ao_scheme_cons_free_list = cons;
137                 cons = ao_scheme_poly_cons(cdr);
138         }
139 }
140
141 void
142 ao_scheme_cons_write(ao_poly c)
143 {
144         struct ao_scheme_cons   *cons = ao_scheme_poly_cons(c);
145         ao_poly                 cdr;
146         int                     first = 1;
147
148         printf("(");
149         while (cons) {
150                 if (!first)
151                         printf(" ");
152                 ao_scheme_poly_write(cons->car);
153                 cdr = cons->cdr;
154                 if (cdr == c) {
155                         printf(" ...");
156                         break;
157                 }
158                 if (ao_scheme_poly_type(cdr) == AO_SCHEME_CONS) {
159                         cons = ao_scheme_poly_cons(cdr);
160                         first = 0;
161                 } else {
162                         printf(" . ");
163                         ao_scheme_poly_write(cdr);
164                         cons = NULL;
165                 }
166         }
167         printf(")");
168 }
169
170 void
171 ao_scheme_cons_display(ao_poly c)
172 {
173         struct ao_scheme_cons   *cons = ao_scheme_poly_cons(c);
174         ao_poly                 cdr;
175
176         while (cons) {
177                 ao_scheme_poly_display(cons->car);
178                 cdr = cons->cdr;
179                 if (cdr == c) {
180                         printf("...");
181                         break;
182                 }
183                 if (ao_scheme_poly_type(cdr) == AO_SCHEME_CONS)
184                         cons = ao_scheme_poly_cons(cdr);
185                 else {
186                         ao_scheme_poly_display(cdr);
187                         cons = NULL;
188                 }
189         }
190 }
191
192 int
193 ao_scheme_cons_length(struct ao_scheme_cons *cons)
194 {
195         int     len = 0;
196         while (cons) {
197                 len++;
198                 cons = ao_scheme_poly_cons(cons->cdr);
199         }
200         return len;
201 }