| 1 | #include <malloc.h> |
| 2 | #include <stdlib.h> |
| 3 | |
| 4 | #include "debug.h" |
| 5 | #include "fdprintf.h" |
| 6 | |
| 7 | #include "parser.h" |
| 8 | |
| 9 | /* compare codes */ |
| 10 | |
| 11 | int codecmp (char *ref, char *str) |
| 12 | { |
| 13 | int sig; |
| 14 | |
| 15 | while (*ref != '\0') { |
| 16 | sig = *str++ - *ref++; |
| 17 | if (sig != 0) { |
| 18 | return (sig > 0) ? 1 : -1; |
| 19 | } |
| 20 | } |
| 21 | |
| 22 | return 0; |
| 23 | } |
| 24 | |
| 25 | /* allocate new element */ |
| 26 | |
| 27 | element_t *newelement (func_t function, int nbops) |
| 28 | { |
| 29 | element_t *new = (element_t *) calloc (1, sizeof (element_t)); |
| 30 | if (new == NULL) { |
| 31 | VERBOSE (ERROR, fdprintf (stdfderr, "can't allocate memory\n")); |
| 32 | return NULL; |
| 33 | } |
| 34 | new->func = function; |
| 35 | new->nbops = nbops; |
| 36 | |
| 37 | return new; |
| 38 | } |
| 39 | |
| 40 | /* functions */ |
| 41 | |
| 42 | #define NB_OPERATORS 7 |
| 43 | |
| 44 | keyword_t operators[NB_OPERATORS] = { |
| 45 | { "+ ", Add, 2, 1 }, |
| 46 | { "+\t", Add, 2, 1 }, |
| 47 | { "- ", Sub, 2, 1 }, |
| 48 | { "- ", Sub, 2, 1 }, |
| 49 | { "*", Mul, 2, 1 }, |
| 50 | { "/", Div, 2, 1 }, |
| 51 | { "^", Pow, 2, 1 } |
| 52 | }; |
| 53 | |
| 54 | #define NB_FUNCTIONS 7 |
| 55 | keyword_t functions[NB_FUNCTIONS] = { |
| 56 | { "sqrt", Sqr, 1, 4 }, |
| 57 | { "pow", Pow, 2, 3 }, |
| 58 | { "cos", Cos, 1, 3 }, |
| 59 | { "sin", Sin, 1, 3 }, |
| 60 | { "atan", Atn, 1, 4 }, |
| 61 | { "exp", Exp, 1, 3 }, |
| 62 | { "log", Log, 1, 3 } |
| 63 | }; |
| 64 | |
| 65 | /* parser function */ |
| 66 | |
| 67 | element_t *parser (char *str, char **next) |
| 68 | { |
| 69 | element_t *root = NULL; |
| 70 | int i, j; |
| 71 | |
| 72 | /* main loop */ |
| 73 | while (*str != '\0') { |
| 74 | int found = 0; |
| 75 | element_t *new = NULL; |
| 76 | VERBOSE (DEBUG, PRINTOUT ("Processing: %s\n", str)); |
| 77 | |
| 78 | /* skip spaces and tabs */ |
| 79 | |
| 80 | if ((*str == ' ') || (*str == '\t')) { |
| 81 | str++; |
| 82 | continue; |
| 83 | } |
| 84 | |
| 85 | /* skip commas */ |
| 86 | |
| 87 | if (*str == ',') { |
| 88 | if (root == NULL) { |
| 89 | return ERROR_OP; |
| 90 | } else if (root->func != Set) { |
| 91 | new = newelement (Set, MAX_OPERANDS); |
| 92 | new->ops[0] = root; |
| 93 | root = new; |
| 94 | } |
| 95 | str++; |
| 96 | continue; |
| 97 | } |
| 98 | |
| 99 | /* check for parent */ |
| 100 | |
| 101 | if (*str == ')') { |
| 102 | if (next != NULL) { |
| 103 | *next = str + 1; |
| 104 | } |
| 105 | return root; |
| 106 | } |
| 107 | if (*str == '(') { |
| 108 | new = parser (str + 1, &str); |
| 109 | if (new == (void *)(-1)) { |
| 110 | return new; |
| 111 | } |
| 112 | if (root) { |
| 113 | for (i = 0, j = 0; i < root->nbops; i++) { |
| 114 | if (root->ops[i] == NULL) { |
| 115 | if (new->func == Set) { |
| 116 | root->ops[i] = new->ops[j++]; |
| 117 | if (new->ops[j] == NULL) { |
| 118 | found = 1; |
| 119 | break; |
| 120 | } |
| 121 | } else { |
| 122 | root->ops[i] = new; |
| 123 | found = 1; |
| 124 | break; |
| 125 | } |
| 126 | } |
| 127 | } |
| 128 | if (!found) { |
| 129 | return ERROR_OP; |
| 130 | } |
| 131 | } else { |
| 132 | return root; |
| 133 | } |
| 134 | } |
| 135 | |
| 136 | /* look for operators */ |
| 137 | |
| 138 | for (i = 0; i < NB_OPERATORS; i++) { |
| 139 | keyword_t *operator = operators + i; |
| 140 | if (codecmp (operator->keyword, str) == 0) { |
| 141 | if ((root) && (root->func == Val)) { |
| 142 | VERBOSE (DEBUG, PRINTOUT ("Oper: %d\n", operator->func)); |
| 143 | new = newelement (operator->func, operator->nbops); |
| 144 | if (new == NULL) { |
| 145 | return ERROR_OP; |
| 146 | } |
| 147 | new->ops[0] = root; |
| 148 | root = new; |
| 149 | } else { |
| 150 | return ERROR_OP; |
| 151 | } |
| 152 | str += operator->offset; |
| 153 | found = 1; |
| 154 | break; |
| 155 | } |
| 156 | } |
| 157 | if (found) { |
| 158 | VERBOSE (DEBUG, PRINTOUT ("stop processing operator\n")); |
| 159 | continue; |
| 160 | } |
| 161 | |
| 162 | /* look for functions */ |
| 163 | |
| 164 | for (i = 0; i < NB_FUNCTIONS; i++) { |
| 165 | keyword_t *function = functions + i; |
| 166 | if (codecmp (function->keyword, str) == 0) { |
| 167 | if (root == NULL) { |
| 168 | VERBOSE (DEBUG, PRINTOUT ("Func: %d\n", function->func)); |
| 169 | new = newelement (function->func, function->nbops); |
| 170 | if (new == NULL) { |
| 171 | return ERROR_OP; |
| 172 | } |
| 173 | root = new; |
| 174 | } else { |
| 175 | return ERROR_OP; |
| 176 | } |
| 177 | str += function->offset; |
| 178 | found = 1; |
| 179 | break; |
| 180 | } |
| 181 | } |
| 182 | if (found) { |
| 183 | VERBOSE (DEBUG, PRINTOUT ("stop processing function\n")); |
| 184 | continue; |
| 185 | } |
| 186 | |
| 187 | /* last attend to detect addition and substraction */ |
| 188 | |
| 189 | if (((*str == '-') || (*str == '+')) && |
| 190 | ((*(str + 1) >= '0') && (*(str + 1) <= '9')) && |
| 191 | ((root) && (root->func == Val))) { |
| 192 | VERBOSE (DEBUG, PRINTOUT ("Oper: %d\n", Add)); |
| 193 | new = newelement (Add, 2); |
| 194 | if (new == NULL) { |
| 195 | return ERROR_OP; |
| 196 | } |
| 197 | new->ops[0] = root; |
| 198 | root = new; |
| 199 | } |
| 200 | |
| 201 | /* look for number */ |
| 202 | |
| 203 | if (((*str >= '0') && (*str <= '9')) || |
| 204 | (*str == '.') || (*str == '-') ||(*str == '+')) { |
| 205 | char *pt; |
| 206 | float value = strtof (str, &pt); |
| 207 | VERBOSE (DEBUG, PRINTOUT ("Value: %f\n", value)); |
| 208 | if (str != pt) { |
| 209 | new = newelement (Val, 1); |
| 210 | new->value = value; |
| 211 | if (new == NULL) { |
| 212 | return ERROR_OP; |
| 213 | } |
| 214 | if (root == NULL) { |
| 215 | root = new; |
| 216 | } else { |
| 217 | if (root->func == Val) { |
| 218 | element_t *set = newelement (Set, MAX_OPERANDS); |
| 219 | if (set == NULL) { |
| 220 | return ERROR_OP; |
| 221 | } |
| 222 | set->ops[0] = root; |
| 223 | root = set; |
| 224 | } |
| 225 | for (i = 0; i < root->nbops; i++) { |
| 226 | if (root->ops[i] == NULL) { |
| 227 | root->ops[i] = new; |
| 228 | found = 1; |
| 229 | break; |
| 230 | } |
| 231 | } |
| 232 | if (!found) { |
| 233 | return ERROR_OP; |
| 234 | } |
| 235 | } |
| 236 | str = pt; |
| 237 | found = 1; |
| 238 | } |
| 239 | } |
| 240 | |
| 241 | /* error */ |
| 242 | |
| 243 | if (!found) { |
| 244 | return ERROR_OP; |
| 245 | } |
| 246 | |
| 247 | } |
| 248 | |
| 249 | return root; |
| 250 | } |
| 251 | |
| 252 | /* print element tree */ |
| 253 | |
| 254 | void print_element (element_t *root, int level) |
| 255 | { |
| 256 | char *func = NULL; |
| 257 | int i; |
| 258 | |
| 259 | if (root == NULL) |
| 260 | return; |
| 261 | |
| 262 | for (i = 0; i < level; i++) { |
| 263 | PRINTOUT (" "); |
| 264 | } |
| 265 | |
| 266 | switch (root->func) { |
| 267 | case Val: func = "Value"; break; |
| 268 | case Set: func = "Set"; break; |
| 269 | case Add: func = "Addition"; break; |
| 270 | case Sub: func = "Subtraction"; break; |
| 271 | case Mul: func = "Multiplication"; break; |
| 272 | case Div: func = "Division"; break; |
| 273 | case Pow: func = "Power"; break; |
| 274 | case Sqr: func = "Square Root"; break; |
| 275 | case Cos: func = "Cosine"; break; |
| 276 | case Sin: func = "Sine"; break; |
| 277 | case Atn: func = "Arc Tangent"; break; |
| 278 | case Log: func = "Logarithm"; break; |
| 279 | case Exp: func = "Exponantial"; break; |
| 280 | } |
| 281 | |
| 282 | PRINTOUT ("Function: %s\n", func); |
| 283 | |
| 284 | if (root->func == Val) { |
| 285 | for (i = 0; i < level; i++) { |
| 286 | PRINTOUT (" "); |
| 287 | } |
| 288 | PRINTOUT ("value: %f\n", root->value); |
| 289 | } else { |
| 290 | for (i = 0; i < root->nbops; i++) { |
| 291 | print_element (root->ops[i], level + 1); |
| 292 | } |
| 293 | } |
| 294 | } |
| 295 | |
| 296 | /* vim: set ts=4 sw=4 et: */ |