jaillex.l revision 223190
1%{ 2/*- 3 * Copyright (c) 2011 James Gritton 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28#include <sys/cdefs.h> 29__FBSDID("$FreeBSD: projects/jailconf/usr.sbin/jail/jaillex.l 223190 2011-06-17 16:21:03Z jamie $"); 30 31#include <err.h> 32#include <stddef.h> 33#include <stdlib.h> 34#include <string.h> 35 36#include "jailp.h" 37#include "y.tab.h" 38 39#define YY_NO_UNPUT 40 41extern int yynerrs; 42 43static ssize_t text2lval(size_t triml, size_t trimr, int tovar); 44 45static int instr; 46static int lineno = 1; 47%} 48 49%start _ DQ 50 51%% 52 53 /* Whitespace or equivalent */ 54<_>[ \t]+ instr = 0; 55<_>#.* ; 56<_>\/\/.* ; 57<_>\/\*([^*]|(\*+([^*\/])))*\*+\/ { 58 const char *s; 59 60 for (s = yytext; s < yytext + yyleng; s++) 61 if (*s == '\n') 62 lineno++; 63 instr = 0; 64 } 65<_>\n { 66 lineno++; 67 instr = 0; 68 } 69 70 /* Reserved tokens */ 71<_>\+= { 72 instr = 0; 73 return PLEQ; 74 } 75<_>[,;={}] { 76 instr = 0; 77 return yytext[0]; 78 } 79 80 /* Atomic (unquoted) strings */ 81<_,DQ>[A-Za-z0-9_!%&()\-.:<>?@\[\]^`|~]+ | 82<_,DQ>\\(.|\n|[0-7]{1,3}|x[0-9A-Fa-f]{1,2}) | 83<_,DQ>[$*+/\\] { 84 (void)text2lval(0, 0, 0); 85 return instr ? STR1 : (instr = 1, STR); 86 } 87 88 /* Single and double quoted strings */ 89<_>'([^\'\\]|\\(.|\n))*' { 90 (void)text2lval(1, 1, 0); 91 return instr ? STR1 : (instr = 1, STR); 92 } 93<_>\"([^"\\]|\\(.|\n))*\" | 94<DQ>[^\"$\\]([^"\\]|\\(.|\n))*\" { 95 size_t skip; 96 ssize_t atvar; 97 98 skip = yytext[0] == '"' ? 1 : 0; 99 atvar = text2lval(skip, 1, 1); 100 if (atvar < 0) 101 BEGIN _; 102 else { 103 /* 104 * The string has a variable inside it. 105 * Go into DQ mode to get the variable 106 * and then the rest of the string. 107 */ 108 BEGIN DQ; 109 yyless(atvar); 110 } 111 return instr ? STR1 : (instr = 1, STR); 112 } 113<DQ>\" BEGIN _; 114 115 /* Variables, single-word or bracketed */ 116<_,DQ>$[A-Za-z_][A-Za-z_0-9]* { 117 (void)text2lval(1, 0, 0); 118 return instr ? VAR1 : (instr = 1, VAR); 119 } 120<_>$\{([^\n{}]|\\(.|\n))*\} | 121<DQ>$\{([^\n\"{}]|\\(.|\n))*\} { 122 (void)text2lval(2, 1, 0); 123 return instr ? VAR1 : (instr = 1, VAR); 124 } 125 126 /* Partially formed bits worth complaining about */ 127<_>\/\*([^*]|(\*+([^*\/])))*\** { 128 warnx("%s line %d: unterminated comment", 129 cfname, lineno); 130 yynerrs++; 131 } 132<_>'([^\n'\\]|\\.)* | 133<_>\"([^\n\"\\]|\\.)* { 134 warnx("%s line %d: unterminated string", 135 cfname, lineno); 136 yynerrs++; 137 } 138<_>$\{([^\n{}]|\\.)* | 139<DQ>$\{([^\n\"{}]|\\.)* { 140 warnx("%s line %d: unterminated variable", 141 cfname, lineno); 142 yynerrs++; 143 } 144 145 /* A hack because "<0>" rules aren't allowed */ 146<_>. return yytext[0]; 147.|\n { 148 BEGIN _; 149 yyless(0); 150 } 151 152%% 153 154void 155yyerror(const char *s) 156{ 157 if (!yytext) 158 warnx("%s line %d: %s", cfname, lineno, s); 159 else if (!yytext[0]) 160 warnx("%s: unexpected EOF", cfname); 161 else 162 warnx("%s line %d: %s: %s", cfname, lineno, yytext, s); 163} 164 165/* 166 * Copy string from yytext to yylval, handling backslash escapes, 167 * and optionally stopping at the beginning of a variable. 168 */ 169static ssize_t 170text2lval(size_t triml, size_t trimr, int tovar) 171{ 172 char *d; 173 const char *s, *se; 174 175 yylval.cs = d = emalloc(yyleng - trimr - triml + 1); 176 se = yytext + (yyleng - trimr); 177 for (s = yytext + triml; s < se; s++, d++) { 178 if (*s != '\\') { 179 if (tovar && *s == '$') { 180 *d = '\0'; 181 return s - yytext; 182 } 183 if (*s == '\n') 184 lineno++; 185 *d = *s; 186 continue; 187 } 188 s++; 189 if (*s >= '0' && *s <= '7') { 190 *d = *s - '0'; 191 if (s + 1 < se && s[1] >= '0' && s[1] <= '7') { 192 *d = 010 * *d + (*++s - '0'); 193 if (s + 1 < se && s[1] >= '0' && s[1] <= '7') 194 *d = 010 * *d + (*++s - '0'); 195 } 196 continue; 197 } 198 switch (*s) { 199 case 'a': *d = '\a'; break; 200 case 'b': *d = '\b'; break; 201 case 'f': *d = '\f'; break; 202 case 'n': *d = '\n'; break; 203 case 'r': *d = '\r'; break; 204 case 't': *d = '\t'; break; 205 case 'v': *d = '\v'; break; 206 case '\n': d--; lineno++; break; 207 default: *d = *s; break; 208 case 'x': 209 *d = 0; 210 if (s + 1 >= se) 211 break; 212 if (s[1] >= '0' && s[1] <= '9') 213 *d = *++s - '0'; 214 else if (s[1] >= 'A' && s[1] <= 'F') 215 *d = *++s + (0xA - 'A'); 216 else if (s[1] >= 'a' && s[1] <= 'a') 217 *d = *++s + (0xa - 'a'); 218 else 219 break; 220 if (s + 1 >= se) 221 break; 222 if (s[1] >= '0' && s[1] <= '9') 223 *d = *d * 0x10 + (*++s - '0'); 224 else if (s[1] >= 'A' && s[1] <= 'F') 225 *d = *d * 0x10 + (*++s + (0xA - 'A')); 226 else if (s[1] >= 'a' && s[1] <= 'a') 227 *d = *d * 0x10 + (*++s + (0xa - 'a')); 228 } 229 } 230 *d = '\0'; 231 return -1; 232} 233