1 %{ 2 /*- 3 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 4 * 5 * Copyright (c) 2011 James Gritton 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include <err.h> 34 #include <stddef.h> 35 #include <stdlib.h> 36 #include <string.h> 37 38 #include "jailp.h" 39 #include "y.tab.h" 40 41 extern int yynerrs; 42 43 static ssize_t text2lval(size_t triml, size_t trimr, int tovar); 44 45 static int instr; 46 static int lineno = 1; 47 48 #define YY_DECL int yylex(void) 49 %} 50 51 %option noyywrap 52 %option noinput 53 %option nounput 54 55 %start _ DQ 56 57 %% 58 59 /* Whitespace or equivalent */ 60 <_>[ \t]+ instr = 0; 61 <_>#.* ; 62 <_>\/\/.* ; 63 <_>\/\*([^*]|(\*+([^*\/])))*\*+\/ { 64 const char *s; 65 66 for (s = yytext; s < yytext + yyleng; s++) 67 if (*s == '\n') 68 lineno++; 69 instr = 0; 70 } 71 <_>\n { 72 lineno++; 73 instr = 0; 74 } 75 76 /* Reserved tokens */ 77 <_>\+= { 78 instr = 0; 79 return PLEQ; 80 } 81 <_>[,;={}] { 82 instr = 0; 83 return yytext[0]; 84 } 85 86 /* Atomic (unquoted) strings */ 87 <_,DQ>[A-Za-z0-9_!%&()\-.:<>?@\[\]^`|~]+ | 88 <_,DQ>\\(.|\n|[0-7]{1,3}|x[0-9A-Fa-f]{1,2}) | 89 <_,DQ>[$*+/\\] { 90 (void)text2lval(0, 0, 0); 91 return instr ? STR1 : (instr = 1, STR); 92 } 93 94 /* Single and double quoted strings */ 95 <_>'([^\'\\]|\\(.|\n))*' { 96 (void)text2lval(1, 1, 0); 97 return instr ? STR1 : (instr = 1, STR); 98 } 99 <_>\"([^"\\]|\\(.|\n))*\" | 100 <DQ>[^\"$\\]([^"\\]|\\(.|\n))*\" { 101 size_t skip; 102 ssize_t atvar; 103 104 skip = yytext[0] == '"' ? 1 : 0; 105 atvar = text2lval(skip, 1, 1); 106 if (atvar < 0) 107 BEGIN _; 108 else { 109 /* 110 * The string has a variable inside it. 111 * Go into DQ mode to get the variable 112 * and then the rest of the string. 113 */ 114 BEGIN DQ; 115 yyless(atvar); 116 } 117 return instr ? STR1 : (instr = 1, STR); 118 } 119 <DQ>\" BEGIN _; 120 121 /* Variables, single-word or bracketed */ 122 <_,DQ>$[A-Za-z_][A-Za-z_0-9]* { 123 (void)text2lval(1, 0, 0); 124 return instr ? VAR1 : (instr = 1, VAR); 125 } 126 <_>$\{([^\n{}]|\\(.|\n))*\} | 127 <DQ>$\{([^\n\"{}]|\\(.|\n))*\} { 128 (void)text2lval(2, 1, 0); 129 return instr ? VAR1 : (instr = 1, VAR); 130 } 131 132 /* Partially formed bits worth complaining about */ 133 <_>\/\*([^*]|(\*+([^*\/])))*\** { 134 warnx("%s line %d: unterminated comment", 135 cfname, lineno); 136 yynerrs++; 137 } 138 <_>'([^\n'\\]|\\.)* | 139 <_>\"([^\n\"\\]|\\.)* { 140 warnx("%s line %d: unterminated string", 141 cfname, lineno); 142 yynerrs++; 143 } 144 <_>$\{([^\n{}]|\\.)* | 145 <DQ>$\{([^\n\"{}]|\\.)* { 146 warnx("%s line %d: unterminated variable", 147 cfname, lineno); 148 yynerrs++; 149 } 150 151 /* A hack because "<0>" rules aren't allowed */ 152 <_>. return yytext[0]; 153 .|\n { 154 BEGIN _; 155 yyless(0); 156 } 157 158 %% 159 160 void 161 yyerror(const char *s) 162 { 163 if (!yytext) 164 warnx("%s line %d: %s", cfname, lineno, s); 165 else if (!yytext[0]) 166 warnx("%s: unexpected EOF", cfname); 167 else 168 warnx("%s line %d: %s: %s", cfname, lineno, yytext, s); 169 } 170 171 /* 172 * Copy string from yytext to yylval, handling backslash escapes, 173 * and optionally stopping at the beginning of a variable. 174 */ 175 static ssize_t 176 text2lval(size_t triml, size_t trimr, int tovar) 177 { 178 char *d; 179 const char *s, *se; 180 181 yylval.cs = d = emalloc(yyleng - trimr - triml + 1); 182 se = yytext + (yyleng - trimr); 183 for (s = yytext + triml; s < se; s++, d++) { 184 if (*s != '\\') { 185 if (tovar && *s == '$') { 186 *d = '\0'; 187 return s - yytext; 188 } 189 if (*s == '\n') 190 lineno++; 191 *d = *s; 192 continue; 193 } 194 s++; 195 if (*s >= '0' && *s <= '7') { 196 *d = *s - '0'; 197 if (s + 1 < se && s[1] >= '0' && s[1] <= '7') { 198 *d = 010 * *d + (*++s - '0'); 199 if (s + 1 < se && s[1] >= '0' && s[1] <= '7') 200 *d = 010 * *d + (*++s - '0'); 201 } 202 continue; 203 } 204 switch (*s) { 205 case 'a': *d = '\a'; break; 206 case 'b': *d = '\b'; break; 207 case 'f': *d = '\f'; break; 208 case 'n': *d = '\n'; break; 209 case 'r': *d = '\r'; break; 210 case 't': *d = '\t'; break; 211 case 'v': *d = '\v'; break; 212 case '\n': d--; lineno++; break; 213 default: *d = *s; break; 214 case 'x': 215 *d = 0; 216 if (s + 1 >= se) 217 break; 218 if (s[1] >= '0' && s[1] <= '9') 219 *d = *++s - '0'; 220 else if (s[1] >= 'A' && s[1] <= 'F') 221 *d = *++s + (0xA - 'A'); 222 else if (s[1] >= 'a' && s[1] <= 'f') 223 *d = *++s + (0xa - 'a'); 224 else 225 break; 226 if (s + 1 >= se) 227 break; 228 if (s[1] >= '0' && s[1] <= '9') 229 *d = *d * 0x10 + (*++s - '0'); 230 else if (s[1] >= 'A' && s[1] <= 'F') 231 *d = *d * 0x10 + (*++s + (0xA - 'A')); 232 else if (s[1] >= 'a' && s[1] <= 'f') 233 *d = *d * 0x10 + (*++s + (0xa - 'a')); 234 } 235 } 236 *d = '\0'; 237 return -1; 238 } 239