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_QIDVEC,
35 	V_QID,
36 
37 	/* casted */
38 	V_U8,
39 	V_U16,
40 	V_U32,
41 };
42 
43 struct value {
44 	int type;
45 	union {
46 		char		*str;
47 		int64_t		 num;
48 		uint8_t		 u8;
49 		uint16_t	 u16;
50 		uint32_t	 u32;
51 		struct {
52 			uint8_t	*msg;
53 			size_t	 len;
54 		} msg;
55 		struct {
56 			uint8_t	*start;
57 			size_t	 len;
58 		} qidvec;
59 		uint8_t		 qid[QIDSIZE];
60 	} v;
61 };
62 
63 enum {
64 	OP_REST,
65 	OP_ASSIGN,
66 	OP_ASSERT,
67 	OP_FUNCALL,
68 	OP_LITERAL,
69 	OP_VAR,
70 	OP_CAST,
71 	OP_CMP_EQ,
72 	OP_CMP_LEQ,
73 	OP_FACCESS,
74 	OP_SFAIL,
75 	OP_VARGS,
76 };
77 
78 struct proc;
79 
80 struct op {
81 	struct op	*next;
82 	int		 type;
83 	union {
84 		struct {
85 			char		*name;
86 			struct op	*expr;
87 		} assign;
88 		struct op		*assert;
89 		struct {
90 			struct proc	*proc;
91 			struct op	*argv;
92 			int		 argc;
93 		} funcall;
94 		struct value literal;
95 		char *var;
96 		struct {
97 			struct op	*expr;
98 			int		 totype;
99 		} cast;
100 		struct {
101 			struct op	*a;
102 			struct op	*b;
103 		} bin_cmp;
104 		struct {
105 			struct op	*expr;
106 			char		*field;
107 		} faccess;
108 		struct {
109 			char		*msg;
110 			struct op	*expr;
111 		} sfail;
112 	} v;
113 };
114 
115 TAILQ_HEAD(bindings, binding);
116 struct binding {
117 	TAILQ_ENTRY(binding)	 entry;
118 	char			*name;
119 	struct value		 val;
120 
121 	/*
122 	 * Hack to support varargs.  We set a special variable named
123 	 * "..." that contains the list of ops that will evaluate to
124 	 * the arguments.
125 	 */
126 	struct op		*raw;
127 };
128 
129 TAILQ_HEAD(envs, env);
130 struct env {
131 	TAILQ_ENTRY(env)	 entry;
132 	struct bindings		 bindings;
133 };
134 
135 TAILQ_HEAD(opstacks, opstack);
136 struct opstack {
137 	TAILQ_ENTRY(opstack)	 entry;
138 	struct op		 base;
139 	struct op		*last;
140 	int			 counter;
141 };
142 
143 TAILQ_HEAD(procs, proc);
144 struct proc {
145 	TAILQ_ENTRY(proc)	 entry;
146 	char			*name;
147 	int			 minargs;
148 	int			 vararg;
149 	char			*args[MAXWELEM];
150 	struct op		*body;
151 	int			(*nativefn)(int);
152 };
153 
154 TAILQ_HEAD(tests, test);
155 struct test {
156 	TAILQ_ENTRY(test)	 entry;
157 	int			 shouldfail;
158 	char			*name;
159 	char			*dir;
160 	struct op		*body;
161 };
162 
163 enum {
164 	EVAL_OK,
165 	EVAL_ERR,
166 	EVAL_SKIP,
167 };
168 
169 int		 global_set(char *, struct op *);
170 
171 struct op	*newop(int);
172 void		 free_op_rec(struct op *);
173 void		 free_op(struct op *);
174 struct op	*op_rest(void);
175 struct op	*op_assign(char *, struct op *);
176 struct op	*op_assert(struct op *);
177 struct op	*op_var(char *);
178 struct op	*op_lit_str(char *);
179 struct op	*op_lit_num(uint64_t);
180 struct op	*op_cmp_eq(struct op *, struct op *);
181 struct op	*op_cmp_leq(struct op *, struct op *);
182 struct op	*op_cast(struct op *, int);
183 struct op	*op_faccess(struct op *, char *);
184 struct op	*op_sfail(struct op *, char *);
185 struct op	*op_vargs(void);
186 
187 void		 ppf_val(FILE *, struct value *);
188 void		 pp_val(struct value *);
189 void		 pp_val(struct value *);
190 const char	*val_type(struct value *);
191 int		 val_trueish(struct value *);
192 int		 val_isnum(struct value *);
193 int64_t		 val_tonum(struct value *);
194 int		 val_eq(struct value *, struct value *);
195 int		 val_leq(struct value *, struct value *);
196 int		 val_cast(struct value *, int);
197 int		 val_faccess(struct value *, const char *, struct value *);
198 void		 pp_op(struct op *);
199 void		 pp_block(struct op *);
200 int		 eval(struct op *);
201 
202 /* funcall */
203 void		 prepare_funcall(void);
204 void		 push_arg(struct op *);
205 struct op	*op_funcall(struct proc *);
206 
207 /* proc */
208 void		 add_builtin_proc(const char *name, int (*)(int), int, int);
209 void		 prepare_proc(void);
210 /* push_arg works on procs too */
211 int		 proc_setup_body(void);
212 void		 proc_done(char *name);
213 void		 block_push(struct op *);
214 struct proc	*proc_by_name(const char *);
215 
216 /* testing */
217 void		 prepare_test(void);
218 void		 test_done(int, char *, char *);
219 
220 /* np.y */
221 void		 loadfile(const char *);
222 
223 #endif