1 /*
2  * Copyright (c) 2021 Omar Polo <op@omarpolo.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #ifndef SCRIPT_H
18 #define SCRIPT_H
19 
20 #include "compat.h"
21 
22 #include <stdio.h>
23 
24 #include "kamid.h"
25 
26 enum {
27 	/* literals */
28 	V_SYM,
29 	V_STR,
30 	V_NUM,
31 
32 	/* foreign */
33 	V_MSG,
34 	V_QID,
35 
36 	/* casted */
37 	V_U8,
38 	V_U16,
39 	V_U32,
40 };
41 
42 struct value {
43 	int type;
44 	union {
45 		char		*str;
46 		int64_t		 num;
47 		uint8_t		 u8;
48 		uint16_t	 u16;
49 		uint32_t	 u32;
50 		struct {
51 			uint8_t	*msg;
52 			size_t	 len;
53 		} msg;
54 		uint8_t		 qid[QIDSIZE];
55 	} v;
56 };
57 
58 enum {
59 	OP_REST,
60 	OP_ASSIGN,
61 	OP_ASSERT,
62 	OP_FUNCALL,
63 	OP_LITERAL,
64 	OP_VAR,
65 	OP_CAST,
66 	OP_CMP_EQ,
67 	OP_FACCESS,
68 	OP_SFAIL,
69 };
70 
71 struct proc;
72 
73 struct op {
74 	struct op	*next;
75 	int		 type;
76 	union {
77 		struct {
78 			char		*name;
79 			struct op	*expr;
80 		} assign;
81 		struct op		*assert;
82 		struct {
83 			struct proc	*proc;
84 			struct op	*argv;
85 			int		 argc;
86 		} funcall;
87 		struct value literal;
88 		char *var;
89 		struct {
90 			struct op	*expr;
91 			int		 totype;
92 		} cast;
93 		struct {
94 			struct op	*a;
95 			struct op	*b;
96 		} cmp_eq;
97 		struct {
98 			struct op	*expr;
99 			char		*field;
100 		} faccess;
101 		struct {
102 			char		*msg;
103 			struct op	*expr;
104 		} sfail;
105 	} v;
106 };
107 
108 TAILQ_HEAD(bindings, binding);
109 struct binding {
110 	TAILQ_ENTRY(binding)	 entry;
111 	char			*name;
112 	struct value		 val;
113 
114 	/*
115 	 * Hack to support varargs.  We set a special variable named
116 	 * "..." that contains the list of ops that will evaluate to
117 	 * the arguments.
118 	 */
119 	struct op		*raw;
120 };
121 
122 TAILQ_HEAD(envs, env);
123 struct env {
124 	TAILQ_ENTRY(env)	 entry;
125 	struct bindings		 bindings;
126 };
127 
128 TAILQ_HEAD(opstacks, opstack);
129 struct opstack {
130 	TAILQ_ENTRY(opstack)	 entry;
131 	struct op		 base;
132 	struct op		*last;
133 	int			 counter;
134 };
135 
136 TAILQ_HEAD(procs, proc);
137 struct proc {
138 	TAILQ_ENTRY(proc)	 entry;
139 	char			*name;
140 	int			 minargs;
141 	int			 vararg;
142 	char			*args[MAXWELEM];
143 	struct op		*body;
144 	int			(*nativefn)(int);
145 };
146 
147 TAILQ_HEAD(tests, test);
148 struct test {
149 	TAILQ_ENTRY(test)	 entry;
150 	int			 shouldfail;
151 	char			*name;
152 	char			*dir;
153 	struct op		*body;
154 };
155 
156 enum {
157 	EVAL_OK,
158 	EVAL_ERR,
159 	EVAL_SKIP,
160 };
161 
162 int		 global_set(char *, struct op *);
163 
164 struct op	*newop(int);
165 void		 free_op(struct op *);
166 struct op	*op_rest(void);
167 struct op	*op_assign(char *, struct op *);
168 struct op	*op_assert(struct op *);
169 struct op	*op_var(char *);
170 struct op	*op_lit_str(char *);
171 struct op	*op_lit_num(uint64_t);
172 struct op	*op_cmp_eq(struct op *, struct op *);
173 struct op	*op_cast(struct op *, int);
174 struct op	*op_faccess(struct op *, char *);
175 struct op	*op_sfail(struct op *, char *);
176 
177 void		 ppf_val(FILE *, struct value *);
178 void		 pp_val(struct value *);
179 int		 val_trueish(struct value *);
180 int		 val_eq(struct value *, struct value *);
181 int		 val_cast(struct value *, int);
182 int		 val_faccess(struct value *, const char *, struct value *);
183 void		 pp_op(struct op *);
184 void		 pp_block(struct op *);
185 int		 eval(struct op *);
186 
187 /* funcall */
188 void		 prepare_funcall(void);
189 void		 push_arg(struct op *);
190 struct op	*op_funcall(struct proc *);
191 
192 /* proc */
193 void		 add_builtin_proc(const char *name, int (*)(int), int, int);
194 void		 prepare_proc(void);
195 /* push_arg works on procs too */
196 int		 proc_setup_body(void);
197 void		 proc_done(char *name);
198 void		 block_push(struct op *);
199 struct proc	*proc_by_name(const char *);
200 
201 /* testing */
202 void		 prepare_test(void);
203 void		 test_done(int, char *, char *);
204 
205 /* np.y */
206 void		 loadfile(const char *);
207 
208 #endif