1 /*
2 * *****************************************************************************
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 *
6 * Copyright (c) 2018-2021 Gavin D. Howard and contributors.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * * Redistributions of source code must retain the above copyright notice, this
12 * list of conditions and the following disclaimer.
13 *
14 * * Redistributions in binary form must reproduce the above copyright notice,
15 * this list of conditions and the following disclaimer in the documentation
16 * and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 *
30 * *****************************************************************************
31 *
32 * Code common to the parsers.
33 *
34 */
35
36 #include <assert.h>
37 #include <stddef.h>
38 #include <stdlib.h>
39 #include <string.h>
40
41 #include <limits.h>
42
43 #include <parse.h>
44 #include <program.h>
45 #include <vm.h>
46
bc_parse_updateFunc(BcParse * p,size_t fidx)47 void bc_parse_updateFunc(BcParse *p, size_t fidx) {
48 p->fidx = fidx;
49 p->func = bc_vec_item(&p->prog->fns, fidx);
50 }
51
bc_parse_pushName(const BcParse * p,char * name,bool var)52 inline void bc_parse_pushName(const BcParse *p, char *name, bool var) {
53 bc_parse_pushIndex(p, bc_program_search(p->prog, name, var));
54 }
55
56 /**
57 * Updates the function, then pushes the instruction and the index. This is a
58 * convenience function.
59 * @param p The parser.
60 * @param inst The instruction to push.
61 * @param idx The index to push.
62 */
bc_parse_update(BcParse * p,uchar inst,size_t idx)63 static void bc_parse_update(BcParse *p, uchar inst, size_t idx) {
64 bc_parse_updateFunc(p, p->fidx);
65 bc_parse_push(p, inst);
66 bc_parse_pushIndex(p, idx);
67 }
68
bc_parse_addString(BcParse * p)69 void bc_parse_addString(BcParse *p) {
70
71 size_t idx;
72
73 idx = bc_program_addString(p->prog, p->l.str.v, p->fidx);
74
75 // Push the string info.
76 bc_parse_update(p, BC_INST_STR, p->fidx);
77 bc_parse_pushIndex(p, idx);
78 }
79
bc_parse_addNum(BcParse * p,const char * string)80 static void bc_parse_addNum(BcParse *p, const char *string) {
81
82 BcVec *consts = &p->func->consts;
83 size_t idx;
84 BcConst *c;
85 BcVec *slabs;
86
87 BC_SIG_ASSERT_LOCKED;
88
89 // Special case 0.
90 if (bc_parse_zero[0] == string[0] && bc_parse_zero[1] == string[1]) {
91 bc_parse_push(p, BC_INST_ZERO);
92 return;
93 }
94
95 // Special case 1.
96 if (bc_parse_one[0] == string[0] && bc_parse_one[1] == string[1]) {
97 bc_parse_push(p, BC_INST_ONE);
98 return;
99 }
100
101 // Get the index.
102 idx = consts->len;
103
104 // Get the right slab.
105 slabs = p->fidx == BC_PROG_MAIN || p->fidx == BC_PROG_READ ?
106 &vm.main_const_slab : &vm.other_slabs;
107
108 // Push an empty constant.
109 c = bc_vec_pushEmpty(consts);
110
111 // Set the fields.
112 c->val = bc_slabvec_strdup(slabs, string);
113 c->base = BC_NUM_BIGDIG_MAX;
114
115 // We need this to be able to tell that the number has not been allocated.
116 bc_num_clear(&c->num);
117
118 bc_parse_update(p, BC_INST_NUM, idx);
119 }
120
bc_parse_number(BcParse * p)121 void bc_parse_number(BcParse *p) {
122
123 #if BC_ENABLE_EXTRA_MATH
124 char *exp = strchr(p->l.str.v, 'e');
125 size_t idx = SIZE_MAX;
126
127 // Do we have a number in scientific notation? If so, add a nul byte where
128 // the e is.
129 if (exp != NULL) {
130 idx = ((size_t) (exp - p->l.str.v));
131 *exp = 0;
132 }
133 #endif // BC_ENABLE_EXTRA_MATH
134
135 bc_parse_addNum(p, p->l.str.v);
136
137 #if BC_ENABLE_EXTRA_MATH
138 // If we have a number in scientific notation...
139 if (exp != NULL) {
140
141 bool neg;
142
143 // Figure out if the exponent is negative.
144 neg = (*((char*) bc_vec_item(&p->l.str, idx + 1)) == BC_LEX_NEG_CHAR);
145
146 // Add the number and instruction.
147 bc_parse_addNum(p, bc_vec_item(&p->l.str, idx + 1 + neg));
148 bc_parse_push(p, BC_INST_LSHIFT + neg);
149 }
150 #endif // BC_ENABLE_EXTRA_MATH
151 }
152
bc_parse_text(BcParse * p,const char * text,bool is_stdin)153 void bc_parse_text(BcParse *p, const char *text, bool is_stdin) {
154
155 BC_SIG_LOCK;
156
157 // Make sure the pointer isn't invalidated.
158 p->func = bc_vec_item(&p->prog->fns, p->fidx);
159 bc_lex_text(&p->l, text, is_stdin);
160
161 BC_SIG_UNLOCK;
162 }
163
bc_parse_reset(BcParse * p)164 void bc_parse_reset(BcParse *p) {
165
166 BC_SIG_ASSERT_LOCKED;
167
168 // Reset the function if it isn't main and switch to main.
169 if (p->fidx != BC_PROG_MAIN) {
170 bc_func_reset(p->func);
171 bc_parse_updateFunc(p, BC_PROG_MAIN);
172 }
173
174 // Reset the lexer.
175 p->l.i = p->l.len;
176 p->l.t = BC_LEX_EOF;
177
178 #if BC_ENABLED
179 if (BC_IS_BC) {
180
181 // Get rid of the bc parser state.
182 p->auto_part = false;
183 bc_vec_npop(&p->flags, p->flags.len - 1);
184 bc_vec_popAll(&p->exits);
185 bc_vec_popAll(&p->conds);
186 bc_vec_popAll(&p->ops);
187 }
188 #endif // BC_ENABLED
189
190 // Reset the program. This might clear the error.
191 bc_program_reset(p->prog);
192
193 // Jump if there is an error.
194 if (BC_ERR(vm.status)) BC_JMP;
195 }
196
197 #ifndef NDEBUG
bc_parse_free(BcParse * p)198 void bc_parse_free(BcParse *p) {
199
200 BC_SIG_ASSERT_LOCKED;
201
202 assert(p != NULL);
203
204 #if BC_ENABLED
205 if (BC_IS_BC) {
206 bc_vec_free(&p->flags);
207 bc_vec_free(&p->exits);
208 bc_vec_free(&p->conds);
209 bc_vec_free(&p->ops);
210 bc_vec_free(&p->buf);
211 }
212 #endif // BC_ENABLED
213
214 bc_lex_free(&p->l);
215 }
216 #endif // NDEBUG
217
bc_parse_init(BcParse * p,BcProgram * prog,size_t func)218 void bc_parse_init(BcParse *p, BcProgram *prog, size_t func) {
219
220 #if BC_ENABLED
221 uint16_t flag = 0;
222 #endif // BC_ENABLED
223
224 BC_SIG_ASSERT_LOCKED;
225
226 assert(p != NULL && prog != NULL);
227
228 #if BC_ENABLED
229 if (BC_IS_BC) {
230
231 // We always want at least one flag set on the flags stack.
232 bc_vec_init(&p->flags, sizeof(uint16_t), BC_DTOR_NONE);
233 bc_vec_push(&p->flags, &flag);
234
235 bc_vec_init(&p->exits, sizeof(BcInstPtr), BC_DTOR_NONE);
236 bc_vec_init(&p->conds, sizeof(size_t), BC_DTOR_NONE);
237 bc_vec_init(&p->ops, sizeof(BcLexType), BC_DTOR_NONE);
238 bc_vec_init(&p->buf, sizeof(char), BC_DTOR_NONE);
239
240 p->auto_part = false;
241 }
242 #endif // BC_ENABLED
243
244 bc_lex_init(&p->l);
245
246 // Set up the function.
247 p->prog = prog;
248 bc_parse_updateFunc(p, func);
249 }
250