1 /* $OpenPackages$ */ 2 /* $OpenBSD: for.c,v 1.39 2007/09/17 09:28:36 espie Exp $ */ 3 /* $NetBSD: for.c,v 1.4 1996/11/06 17:59:05 christos Exp $ */ 4 5 /* 6 * Copyright (c) 1999 Marc Espie. 7 * 8 * Extensive code modifications for the OpenBSD project. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 22 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OPENBSD 23 * PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 25 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * Copyright (c) 1992, The Regents of the University of California. 34 * All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions 38 * are met: 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 3. Neither the name of the University nor the names of its contributors 45 * may be used to endorse or promote products derived from this software 46 * without specific prior written permission. 47 * 48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 58 * SUCH DAMAGE. 59 */ 60 61 #include <assert.h> 62 #include <ctype.h> 63 #include <stddef.h> 64 #include <stdio.h> 65 #include <stdlib.h> 66 #include <string.h> 67 #include "config.h" 68 #include "defines.h" 69 #include "buf.h" 70 #include "for.h" 71 #include "lst.h" 72 #include "error.h" 73 #include "var.h" 74 #include "lowparse.h" 75 #include "str.h" 76 #include "memory.h" 77 78 /* 79 * For statements are of the form: 80 * 81 * .for <variable> [variable...] in <varlist> 82 * ... 83 * .endfor 84 * 85 * The trick is to look for the matching .end inside .for loops. 86 * To do that, we keep track of the nesting level of .for loops 87 * and matching .endfor statements, accumulating all statements between 88 * the initial .for loop and the matching .endfor, 89 * then we evaluate the .for loop for each variable in the varlist. 90 */ 91 92 /* State of a for loop. */ 93 struct For_ { 94 char *text; /* Unexpanded text */ 95 LIST vars; /* List of variables */ 96 LstNode var; /* Current var */ 97 int nvars; /* Total number of vars */ 98 LIST lst; /* List of items */ 99 size_t guess; /* Estimated expansion size */ 100 BUFFER buf; /* Accumulating text */ 101 unsigned long lineno; /* Line number at start of loop */ 102 unsigned long level; /* Nesting level */ 103 bool freeold; 104 }; 105 106 /* ForExec(value, handle); 107 * Expands next variable in loop sequence described by handle to value. */ 108 static void ForExec(void *, void *); 109 110 /* n = build_words_list(lst, s); 111 * Cuts string into words, pushes words into list, in reverse order, 112 * because Parse_FromString works as a stack. 113 * Returns the number of words. */ 114 static unsigned long build_words_list(Lst, const char *); 115 116 static unsigned long 117 build_words_list(Lst lst, const char *s) 118 { 119 const char *end, *wrd; 120 unsigned long n; 121 122 n = 0; 123 end = s; 124 125 while ((wrd = iterate_words(&end)) != NULL) { 126 Lst_AtFront(lst, escape_dupi(wrd, end, "\"'")); 127 n++; 128 } 129 return n; 130 } 131 132 For * 133 For_Eval(const char *line) 134 { 135 const char *ptr = line; 136 const char *wrd; 137 char *sub; 138 const char *endVar; 139 For *arg; 140 unsigned long n; 141 142 while (isspace(*ptr)) 143 ptr++; 144 145 /* Parse loop. */ 146 147 arg = emalloc(sizeof(*arg)); 148 arg->nvars = 0; 149 Lst_Init(&arg->vars); 150 151 for (;;) { 152 /* Grab the variables. */ 153 for (wrd = ptr; *ptr && !isspace(*ptr); ptr++) 154 continue; 155 if (ptr - wrd == 0) { 156 Parse_Error(PARSE_FATAL, "Syntax error in for"); 157 return 0; 158 } 159 endVar = ptr++; 160 while (isspace(*ptr)) 161 ptr++; 162 /* End of variable list ? */ 163 if (endVar - wrd == 2 && wrd[0] == 'i' && wrd[1] == 'n') 164 break; 165 Lst_AtEnd(&arg->vars, Var_NewLoopVar(wrd, endVar)); 166 arg->nvars++; 167 } 168 if (arg->nvars == 0) { 169 Parse_Error(PARSE_FATAL, "Missing variable in for"); 170 return 0; 171 } 172 173 /* Make a list with the remaining words. */ 174 sub = Var_Subst(ptr, NULL, false); 175 if (DEBUG(FOR)) { 176 LstNode ln; 177 (void)fprintf(stderr, "For: Iterator "); 178 for (ln = Lst_First(&arg->vars); ln != NULL; ln = Lst_Adv(ln)) 179 (void)fprintf(stderr, "%s ", (char *)Lst_Datum(ln)); 180 (void)fprintf(stderr, "List %s\n", sub); 181 } 182 183 Lst_Init(&arg->lst); 184 n = build_words_list(&arg->lst, sub); 185 free(sub); 186 if (arg->nvars != 1 && n % arg->nvars != 0) { 187 Parse_Error(PARSE_FATAL, "Wrong number of items in for loop"); 188 return 0; 189 } 190 arg->lineno = Parse_Getlineno(); 191 arg->level = 1; 192 Buf_Init(&arg->buf, 0); 193 194 return arg; 195 } 196 197 198 bool 199 For_Accumulate(For *arg, const char *line) 200 { 201 const char *ptr = line; 202 203 assert(arg->level > 0); 204 205 if (*ptr == '.') { 206 207 for (ptr++; isspace(*ptr); ptr++) 208 continue; 209 210 if (strncmp(ptr, "endfor", 6) == 0 && 211 (isspace(ptr[6]) || !ptr[6])) { 212 if (DEBUG(FOR)) 213 (void)fprintf(stderr, "For: end for %lu\n", 214 arg->level); 215 /* If matching endfor, don't add line to buffer. */ 216 if (--arg->level == 0) 217 return false; 218 } 219 else if (strncmp(ptr, "for", 3) == 0 && 220 isspace(ptr[3])) { 221 arg->level++; 222 if (DEBUG(FOR)) 223 (void)fprintf(stderr, "For: new loop %lu\n", 224 arg->level); 225 } 226 } 227 Buf_AddString(&arg->buf, line); 228 Buf_AddChar(&arg->buf, '\n'); 229 return true; 230 } 231 232 233 #define GUESS_EXPANSION 32 234 static void 235 ForExec(void *valuep, void *argp) 236 { 237 char *value = (char *)valuep; 238 For *arg = (For *)argp; 239 BUFFER buf; 240 241 /* Parse_FromString pushes stuff back, so we need to go over vars in 242 reverse. */ 243 if (arg->var == NULL) { 244 arg->var = Lst_Last(&arg->vars); 245 arg->text = Buf_Retrieve(&arg->buf); 246 arg->freeold = false; 247 } 248 249 if (DEBUG(FOR)) 250 (void)fprintf(stderr, "--- %s = %s\n", 251 (char *)Lst_Datum(arg->var), value); 252 Buf_Init(&buf, arg->guess); 253 Var_SubstVar(&buf, arg->text, Lst_Datum(arg->var), value); 254 if (arg->freeold) 255 free(arg->text); 256 arg->text = Buf_Retrieve(&buf); 257 arg->freeold = true; 258 arg->var = Lst_Rev(arg->var); 259 if (arg->var == NULL) 260 Parse_FromString(arg->text, arg->lineno); 261 } 262 263 264 void 265 For_Run(For *arg) 266 { 267 arg->text = Buf_Retrieve(&arg->buf); 268 arg->guess = Buf_Size(&arg->buf) + GUESS_EXPANSION; 269 270 arg->var = NULL; 271 Lst_ForEach(&arg->lst, ForExec, arg); 272 Buf_Destroy(&arg->buf); 273 Lst_Destroy(&arg->vars, (SimpleProc)Var_DeleteLoopVar); 274 Lst_Destroy(&arg->lst, (SimpleProc)free); 275 free(arg); 276 } 277