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 BC_SIG_LOCK;
74
75 idx = bc_program_addString(p->prog, p->l.str.v, p->fidx);
76
77 // Push the string info.
78 bc_parse_update(p, BC_INST_STR, p->fidx);
79 bc_parse_pushIndex(p, idx);
80
81 BC_SIG_UNLOCK;
82 }
83
bc_parse_addNum(BcParse * p,const char * string)84 static void bc_parse_addNum(BcParse *p, const char *string) {
85
86 BcVec *consts = &p->func->consts;
87 size_t idx;
88 BcConst *c;
89 BcVec *slabs;
90
91 // Special case 0.
92 if (bc_parse_zero[0] == string[0] && bc_parse_zero[1] == string[1]) {
93 bc_parse_push(p, BC_INST_ZERO);
94 return;
95 }
96
97 // Special case 1.
98 if (bc_parse_one[0] == string[0] && bc_parse_one[1] == string[1]) {
99 bc_parse_push(p, BC_INST_ONE);
100 return;
101 }
102
103 // Get the index.
104 idx = consts->len;
105
106 BC_SIG_LOCK;
107
108 // Get the right slab.
109 slabs = p->fidx == BC_PROG_MAIN || p->fidx == BC_PROG_READ ?
110 &vm.main_const_slab : &vm.other_slabs;
111
112 // Push an empty constant.
113 c = bc_vec_pushEmpty(consts);
114
115 // Set the fields.
116 c->val = bc_slabvec_strdup(slabs, string);
117 c->base = BC_NUM_BIGDIG_MAX;
118
119 // We need this to be able to tell that the number has not been allocated.
120 bc_num_clear(&c->num);
121
122 bc_parse_update(p, BC_INST_NUM, idx);
123
124 BC_SIG_UNLOCK;
125 }
126
bc_parse_number(BcParse * p)127 void bc_parse_number(BcParse *p) {
128
129 #if BC_ENABLE_EXTRA_MATH
130 char *exp = strchr(p->l.str.v, 'e');
131 size_t idx = SIZE_MAX;
132
133 // Do we have a number in scientific notation? If so, add a nul byte where
134 // the e is.
135 if (exp != NULL) {
136 idx = ((size_t) (exp - p->l.str.v));
137 *exp = 0;
138 }
139 #endif // BC_ENABLE_EXTRA_MATH
140
141 bc_parse_addNum(p, p->l.str.v);
142
143 #if BC_ENABLE_EXTRA_MATH
144 // If we have a number in scientific notation...
145 if (exp != NULL) {
146
147 bool neg;
148
149 // Figure out if the exponent is negative.
150 neg = (*((char*) bc_vec_item(&p->l.str, idx + 1)) == BC_LEX_NEG_CHAR);
151
152 // Add the number and instruction.
153 bc_parse_addNum(p, bc_vec_item(&p->l.str, idx + 1 + neg));
154 bc_parse_push(p, BC_INST_LSHIFT + neg);
155 }
156 #endif // BC_ENABLE_EXTRA_MATH
157 }
158
bc_parse_text(BcParse * p,const char * text,bool is_stdin)159 void bc_parse_text(BcParse *p, const char *text, bool is_stdin) {
160
161 // Make sure the pointer isn't invalidated.
162 p->func = bc_vec_item(&p->prog->fns, p->fidx);
163 bc_lex_text(&p->l, text, is_stdin);
164 }
165
bc_parse_reset(BcParse * p)166 void bc_parse_reset(BcParse *p) {
167
168 BC_SIG_ASSERT_LOCKED;
169
170 // Reset the function if it isn't main and switch to main.
171 if (p->fidx != BC_PROG_MAIN) {
172 bc_func_reset(p->func);
173 bc_parse_updateFunc(p, BC_PROG_MAIN);
174 }
175
176 // Reset the lexer.
177 p->l.i = p->l.len;
178 p->l.t = BC_LEX_EOF;
179
180 #if BC_ENABLED
181 if (BC_IS_BC) {
182
183 // Get rid of the bc parser state.
184 p->auto_part = false;
185 bc_vec_npop(&p->flags, p->flags.len - 1);
186 bc_vec_popAll(&p->exits);
187 bc_vec_popAll(&p->conds);
188 bc_vec_popAll(&p->ops);
189 }
190 #endif // BC_ENABLED
191
192 // Reset the program. This might clear the error.
193 bc_program_reset(p->prog);
194
195 // Jump if there is an error.
196 if (BC_ERR(vm.status)) BC_JMP;
197 }
198
199 #ifndef NDEBUG
bc_parse_free(BcParse * p)200 void bc_parse_free(BcParse *p) {
201
202 BC_SIG_ASSERT_LOCKED;
203
204 assert(p != NULL);
205
206 #if BC_ENABLED
207 if (BC_IS_BC) {
208 bc_vec_free(&p->flags);
209 bc_vec_free(&p->exits);
210 bc_vec_free(&p->conds);
211 bc_vec_free(&p->ops);
212 bc_vec_free(&p->buf);
213 }
214 #endif // BC_ENABLED
215
216 bc_lex_free(&p->l);
217 }
218 #endif // NDEBUG
219
bc_parse_init(BcParse * p,BcProgram * prog,size_t func)220 void bc_parse_init(BcParse *p, BcProgram *prog, size_t func) {
221
222 #if BC_ENABLED
223 uint16_t flag = 0;
224 #endif // BC_ENABLED
225
226 BC_SIG_ASSERT_LOCKED;
227
228 assert(p != NULL && prog != NULL);
229
230 #if BC_ENABLED
231 if (BC_IS_BC) {
232
233 // We always want at least one flag set on the flags stack.
234 bc_vec_init(&p->flags, sizeof(uint16_t), BC_DTOR_NONE);
235 bc_vec_push(&p->flags, &flag);
236
237 bc_vec_init(&p->exits, sizeof(BcInstPtr), BC_DTOR_NONE);
238 bc_vec_init(&p->conds, sizeof(size_t), BC_DTOR_NONE);
239 bc_vec_init(&p->ops, sizeof(BcLexType), BC_DTOR_NONE);
240 bc_vec_init(&p->buf, sizeof(char), BC_DTOR_NONE);
241
242 p->auto_part = false;
243 }
244 #endif // BC_ENABLED
245
246 bc_lex_init(&p->l);
247
248 // Set up the function.
249 p->prog = prog;
250 bc_parse_updateFunc(p, func);
251 }
252