1 /* $OpenBSD: db_lex.c,v 1.15 2020/10/15 03:14:00 deraadt Exp $ */ 2 /* $NetBSD: db_lex.c,v 1.8 1996/02/05 01:57:05 christos Exp $ */ 3 4 /* 5 * Mach Operating System 6 * Copyright (c) 1993,1992,1991,1990 Carnegie Mellon University 7 * All Rights Reserved. 8 * 9 * Permission to use, copy, modify and distribute this software and its 10 * documentation is hereby granted, provided that both the copyright 11 * notice and this permission notice appear in all copies of the 12 * software, derivative works or modified versions, and any portions 13 * thereof, and that both notices appear in supporting documentation. 14 * 15 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 16 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 17 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 18 * 19 * Carnegie Mellon requests users of this software to return to 20 * 21 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 22 * School of Computer Science 23 * Carnegie Mellon University 24 * Pittsburgh PA 15213-3890 25 * 26 * any improvements or extensions that they make and grant Carnegie Mellon 27 * the rights to redistribute these changes. 28 * 29 * Author: David B. Golub, Carnegie Mellon University 30 * Date: 7/90 31 */ 32 33 /* 34 * Lexical analyzer. 35 */ 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 39 #include <machine/db_machdep.h> 40 41 #include <ddb/db_lex.h> 42 #include <ddb/db_output.h> 43 #include <ddb/db_command.h> 44 #include <ddb/db_extern.h> 45 #include <ddb/db_var.h> 46 47 char db_line[120]; 48 char * db_lp, *db_endlp; 49 50 db_expr_t db_tok_number; 51 char db_tok_string[TOK_STRING_SIZE]; 52 53 void db_flush_line(void); 54 int db_read_char(void); 55 void db_unread_char(int); 56 57 int 58 db_read_line(void) 59 { 60 int i; 61 62 i = db_readline(db_line, sizeof(db_line)); 63 if (i == 0) 64 return (0); /* EOI */ 65 db_lp = db_line; 66 db_endlp = db_lp + i; 67 return (i); 68 } 69 70 void 71 db_flush_line(void) 72 { 73 db_lp = db_line; 74 db_endlp = db_line; 75 } 76 77 int db_look_char = 0; 78 79 int 80 db_read_char(void) 81 { 82 int c; 83 84 if (db_look_char != 0) { 85 c = db_look_char; 86 db_look_char = 0; 87 } else if (db_lp >= db_endlp) 88 c = -1; 89 else 90 c = *db_lp++; 91 return (c); 92 } 93 94 void 95 db_unread_char(int c) 96 { 97 db_look_char = c; 98 } 99 100 int db_look_token = 0; 101 102 void 103 db_unread_token(int t) 104 { 105 db_look_token = t; 106 } 107 108 int 109 db_read_token(void) 110 { 111 int t; 112 113 if (db_look_token) { 114 t = db_look_token; 115 db_look_token = 0; 116 } else 117 t = db_lex(); 118 return (t); 119 } 120 121 void 122 db_flush_lex(void) 123 { 124 db_flush_line(); 125 db_look_char = 0; 126 db_look_token = 0; 127 } 128 129 int 130 db_lex(void) 131 { 132 int c; 133 134 c = db_read_char(); 135 while (c <= ' ' || c > '~') { 136 if (c == '\n' || c == -1) 137 return (tEOL); 138 c = db_read_char(); 139 } 140 141 if (c >= '0' && c <= '9') { 142 /* number */ 143 int r, digit = 0; 144 145 if (c > '0') 146 r = db_radix; 147 else { 148 c = db_read_char(); 149 if (c == 'O' || c == 'o') 150 r = 8; 151 else if (c == 'T' || c == 't') 152 r = 10; 153 else if (c == 'X' || c == 'x') 154 r = 16; 155 else { 156 r = db_radix; 157 db_unread_char(c); 158 } 159 c = db_read_char(); 160 } 161 db_tok_number = 0; 162 for (;;) { 163 if (c >= '0' && c <= ((r == 8) ? '7' : '9')) 164 digit = c - '0'; 165 else if (r == 16 && ((c >= 'A' && c <= 'F') || 166 (c >= 'a' && c <= 'f'))) { 167 if (c >= 'a') 168 digit = c - 'a' + 10; 169 else if (c >= 'A') 170 digit = c - 'A' + 10; 171 } else 172 break; 173 db_tok_number = db_tok_number * r + digit; 174 c = db_read_char(); 175 } 176 if ((c >= '0' && c <= '9') || 177 (c >= 'A' && c <= 'Z') || 178 (c >= 'a' && c <= 'z') || 179 (c == '_')) { 180 db_error("Bad character in number\n"); 181 /*NOTREACHED*/ 182 } 183 db_unread_char(c); 184 return (tNUMBER); 185 } 186 if ((c >= 'A' && c <= 'Z') || 187 (c >= 'a' && c <= 'z') || 188 c == '_' || c == '\\') { 189 /* string */ 190 char *cp; 191 192 cp = db_tok_string; 193 if (c == '\\') { 194 c = db_read_char(); 195 if (c == '\n' || c == -1) { 196 db_error("Bad escape\n"); 197 /*NOTREACHED*/ 198 } 199 } 200 *cp++ = c; 201 while (1) { 202 c = db_read_char(); 203 if ((c >= 'A' && c <= 'Z') || 204 (c >= 'a' && c <= 'z') || 205 (c >= '0' && c <= '9') || 206 c == '_' || c == '\\' || c == ':') { 207 if (c == '\\') { 208 c = db_read_char(); 209 if (c == '\n' || c == -1) { 210 db_error("Bad escape\n"); 211 /*NOTREACHED*/ 212 } 213 } 214 *cp++ = c; 215 if (cp == db_tok_string+sizeof(db_tok_string)) { 216 db_error("String too long\n"); 217 /*NOTREACHED*/ 218 } 219 continue; 220 } else { 221 *cp = '\0'; 222 break; 223 } 224 } 225 db_unread_char(c); 226 return (tIDENT); 227 } 228 229 switch (c) { 230 case '+': 231 return (tPLUS); 232 case '-': 233 return (tMINUS); 234 case '.': 235 c = db_read_char(); 236 if (c == '.') 237 return (tDOTDOT); 238 db_unread_char(c); 239 return (tDOT); 240 case '*': 241 return (tSTAR); 242 case '/': 243 return (tSLASH); 244 case '=': 245 return (tEQ); 246 case '%': 247 return (tPCT); 248 case '#': 249 return (tHASH); 250 case '(': 251 return (tLPAREN); 252 case ')': 253 return (tRPAREN); 254 case ',': 255 return (tCOMMA); 256 case '"': 257 return (tDITTO); 258 case '$': 259 return (tDOLLAR); 260 case '!': 261 return (tEXCL); 262 case '<': 263 c = db_read_char(); 264 if (c == '<') 265 return (tSHIFT_L); 266 db_unread_char(c); 267 break; 268 case '>': 269 c = db_read_char(); 270 if (c == '>') 271 return (tSHIFT_R); 272 db_unread_char(c); 273 break; 274 case -1: 275 return (tEOF); 276 } 277 db_printf("Bad character\n"); 278 db_flush_lex(); 279 return (tEOF); 280 } 281