| 1 | /* |
| 2 | * Mach Operating System |
| 3 | * Copyright (c) 1991,1990 Carnegie Mellon University |
| 4 | * All Rights Reserved. |
| 5 | * |
| 6 | * Permission to use, copy, modify and distribute this software and its |
| 7 | * documentation is hereby granted, provided that both the copyright |
| 8 | * notice and this permission notice appear in all copies of the |
| 9 | * software, derivative works or modified versions, and any portions |
| 10 | * thereof, and that both notices appear in supporting documentation. |
| 11 | * |
| 12 | * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS |
| 13 | * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR |
| 14 | * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. |
| 15 | * |
| 16 | * Carnegie Mellon requests users of this software to return to |
| 17 | * |
| 18 | * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU |
| 19 | * School of Computer Science |
| 20 | * Carnegie Mellon University |
| 21 | * Pittsburgh PA 15213-3890 |
| 22 | * |
| 23 | * any improvements or extensions that they make and grant Carnegie the |
| 24 | * rights to redistribute these changes. |
| 25 | */ |
| 26 | /* |
| 27 | * HISTORY |
| 28 | * $Log: db_lex.c,v $ |
| 29 | * Revision 1.1 1992/03/25 21:45:13 pace |
| 30 | * Initial revision |
| 31 | * |
| 32 | * Revision 2.3 91/02/05 17:06:36 mrt |
| 33 | * Changed to new Mach copyright |
| 34 | * [91/01/31 16:18:20 mrt] |
| 35 | * |
| 36 | * Revision 2.2 90/08/27 21:51:10 dbg |
| 37 | * Add 'dotdot' token. |
| 38 | * [90/08/22 dbg] |
| 39 | * |
| 40 | * Allow backslash to quote any character into an identifier. |
| 41 | * Allow colon in identifier for symbol table qualification. |
| 42 | * [90/08/16 dbg] |
| 43 | * Reduce lint. |
| 44 | * [90/08/07 dbg] |
| 45 | * Created. |
| 46 | * [90/07/25 dbg] |
| 47 | * |
| 48 | */ |
| 49 | /* |
| 50 | * Author: David B. Golub, Carnegie Mellon University |
| 51 | * Date: 7/90 |
| 52 | */ |
| 53 | /* |
| 54 | * Lexical analyzer. |
| 55 | */ |
| 56 | #include <ddb/db_lex.h> |
| 57 | |
| 58 | char db_line[120]; |
| 59 | char * db_lp, *db_endlp; |
| 60 | |
| 61 | int |
| 62 | db_read_line() |
| 63 | { |
| 64 | int i; |
| 65 | |
| 66 | i = db_readline(db_line, sizeof(db_line)); |
| 67 | if (i == 0) |
| 68 | return (0); /* EOI */ |
| 69 | db_lp = db_line; |
| 70 | db_endlp = db_lp + i; |
| 71 | return (i); |
| 72 | } |
| 73 | |
| 74 | void |
| 75 | db_flush_line() |
| 76 | { |
| 77 | db_lp = db_line; |
| 78 | db_endlp = db_line; |
| 79 | } |
| 80 | |
| 81 | int db_look_char = 0; |
| 82 | |
| 83 | int |
| 84 | db_read_char() |
| 85 | { |
| 86 | int c; |
| 87 | |
| 88 | if (db_look_char != 0) { |
| 89 | c = db_look_char; |
| 90 | db_look_char = 0; |
| 91 | } |
| 92 | else if (db_lp >= db_endlp) |
| 93 | c = -1; |
| 94 | else |
| 95 | c = *db_lp++; |
| 96 | return (c); |
| 97 | } |
| 98 | |
| 99 | void |
| 100 | db_unread_char(c) |
| 101 | { |
| 102 | db_look_char = c; |
| 103 | } |
| 104 | |
| 105 | int db_look_token = 0; |
| 106 | |
| 107 | void |
| 108 | db_unread_token(t) |
| 109 | int t; |
| 110 | { |
| 111 | db_look_token = t; |
| 112 | } |
| 113 | |
| 114 | int |
| 115 | db_read_token() |
| 116 | { |
| 117 | int t; |
| 118 | |
| 119 | if (db_look_token) { |
| 120 | t = db_look_token; |
| 121 | db_look_token = 0; |
| 122 | } |
| 123 | else |
| 124 | t = db_lex(); |
| 125 | return (t); |
| 126 | } |
| 127 | |
| 128 | int db_tok_number; |
| 129 | char db_tok_string[TOK_STRING_SIZE]; |
| 130 | |
| 131 | int db_radix = 16; |
| 132 | |
| 133 | void |
| 134 | db_flush_lex() |
| 135 | { |
| 136 | db_flush_line(); |
| 137 | db_look_char = 0; |
| 138 | db_look_token = 0; |
| 139 | } |
| 140 | |
| 141 | int |
| 142 | db_lex() |
| 143 | { |
| 144 | int c; |
| 145 | |
| 146 | c = db_read_char(); |
| 147 | while (c <= ' ' || c > '~') { |
| 148 | if (c == '\n' || c == -1) |
| 149 | return (tEOL); |
| 150 | c = db_read_char(); |
| 151 | } |
| 152 | |
| 153 | if (c >= '0' && c <= '9') { |
| 154 | /* number */ |
| 155 | int r, digit; |
| 156 | |
| 157 | if (c > '0') |
| 158 | r = db_radix; |
| 159 | else { |
| 160 | c = db_read_char(); |
| 161 | if (c == 'O' || c == 'o') |
| 162 | r = 8; |
| 163 | else if (c == 'T' || c == 't') |
| 164 | r = 10; |
| 165 | else if (c == 'X' || c == 'x') |
| 166 | r = 16; |
| 167 | else { |
| 168 | r = db_radix; |
| 169 | db_unread_char(c); |
| 170 | } |
| 171 | c = db_read_char(); |
| 172 | } |
| 173 | db_tok_number = 0; |
| 174 | for (;;) { |
| 175 | if (c >= '0' && c <= ((r == 8) ? '7' : '9')) |
| 176 | digit = c - '0'; |
| 177 | else if (r == 16 && ((c >= 'A' && c <= 'F') || |
| 178 | (c >= 'a' && c <= 'f'))) { |
| 179 | if (c >= 'a') |
| 180 | digit = c - 'a' + 10; |
| 181 | else if (c >= 'A') |
| 182 | digit = c - 'A' + 10; |
| 183 | } |
| 184 | else |
| 185 | break; |
| 186 | db_tok_number = db_tok_number * r + digit; |
| 187 | c = db_read_char(); |
| 188 | } |
| 189 | if ((c >= '0' && c <= '9') || |
| 190 | (c >= 'A' && c <= 'Z') || |
| 191 | (c >= 'a' && c <= 'z') || |
| 192 | (c == '_')) |
| 193 | { |
| 194 | db_error("Bad character in number\n"); |
| 195 | db_flush_lex(); |
| 196 | return (tEOF); |
| 197 | } |
| 198 | db_unread_char(c); |
| 199 | return (tNUMBER); |
| 200 | } |
| 201 | if ((c >= 'A' && c <= 'Z') || |
| 202 | (c >= 'a' && c <= 'z') || |
| 203 | c == '_' || c == '\\') |
| 204 | { |
| 205 | /* string */ |
| 206 | char *cp; |
| 207 | |
| 208 | cp = db_tok_string; |
| 209 | if (c == '\\') { |
| 210 | c = db_read_char(); |
| 211 | if (c == '\n' || c == -1) |
| 212 | db_error("Bad escape\n"); |
| 213 | } |
| 214 | *cp++ = c; |
| 215 | while (1) { |
| 216 | c = db_read_char(); |
| 217 | if ((c >= 'A' && c <= 'Z') || |
| 218 | (c >= 'a' && c <= 'z') || |
| 219 | (c >= '0' && c <= '9') || |
| 220 | c == '_' || c == '\\' || c == ':') |
| 221 | { |
| 222 | if (c == '\\') { |
| 223 | c = db_read_char(); |
| 224 | if (c == '\n' || c == -1) |
| 225 | db_error("Bad escape\n"); |
| 226 | } |
| 227 | *cp++ = c; |
| 228 | if (cp == db_tok_string+sizeof(db_tok_string)) { |
| 229 | db_error("String too long\n"); |
| 230 | db_flush_lex(); |
| 231 | return (tEOF); |
| 232 | } |
| 233 | continue; |
| 234 | } |
| 235 | else { |
| 236 | *cp = '\0'; |
| 237 | break; |
| 238 | } |
| 239 | } |
| 240 | db_unread_char(c); |
| 241 | return (tIDENT); |
| 242 | } |
| 243 | |
| 244 | switch (c) { |
| 245 | case '+': |
| 246 | return (tPLUS); |
| 247 | case '-': |
| 248 | return (tMINUS); |
| 249 | case '.': |
| 250 | c = db_read_char(); |
| 251 | if (c == '.') |
| 252 | return (tDOTDOT); |
| 253 | db_unread_char(c); |
| 254 | return (tDOT); |
| 255 | case '*': |
| 256 | return (tSTAR); |
| 257 | case '/': |
| 258 | return (tSLASH); |
| 259 | case '=': |
| 260 | return (tEQ); |
| 261 | case '%': |
| 262 | return (tPCT); |
| 263 | case '#': |
| 264 | return (tHASH); |
| 265 | case '(': |
| 266 | return (tLPAREN); |
| 267 | case ')': |
| 268 | return (tRPAREN); |
| 269 | case ',': |
| 270 | return (tCOMMA); |
| 271 | case '"': |
| 272 | return (tDITTO); |
| 273 | case '$': |
| 274 | return (tDOLLAR); |
| 275 | case '!': |
| 276 | return (tEXCL); |
| 277 | case '<': |
| 278 | c = db_read_char(); |
| 279 | if (c == '<') |
| 280 | return (tSHIFT_L); |
| 281 | db_unread_char(c); |
| 282 | break; |
| 283 | case '>': |
| 284 | c = db_read_char(); |
| 285 | if (c == '>') |
| 286 | return (tSHIFT_R); |
| 287 | db_unread_char(c); |
| 288 | break; |
| 289 | case -1: |
| 290 | return (tEOF); |
| 291 | } |
| 292 | db_printf("Bad character\n"); |
| 293 | db_flush_lex(); |
| 294 | return (tEOF); |
| 295 | } |