1/* $OpenBSD: sub.c,v 1.18 2016/10/11 06:54:05 martijn Exp $ */ 2/* $NetBSD: sub.c,v 1.4 1995/03/21 09:04:50 cgd Exp $ */ 3 4/* sub.c: This file contains the substitution routines for the ed 5 line editor */ 6/*- 7 * Copyright (c) 1993 Andrew Moore, Talke Studio. 8 * All rights reserved. 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 AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32#include <limits.h> 33#include <regex.h> 34#include <signal.h> 35#include <stdio.h> 36#include <stdlib.h> 37#include <string.h> 38 39#include "ed.h" 40 41static char *extract_subst_template(void); 42static int substitute_matching_text(regex_t *, line_t *, int, int); 43static int apply_subst_template(char *, regmatch_t *, int, int); 44 45static char *rhbuf; /* rhs substitution buffer */ 46static int rhbufsz; /* rhs substitution buffer size */ 47static int rhbufi; /* rhs substitution buffer index */ 48 49/* extract_subst_tail: extract substitution tail from the command buffer */ 50int 51extract_subst_tail(int *flagp, int *np) 52{ 53 char delimiter; 54 55 *flagp = *np = 0; 56 if ((delimiter = *ibufp) == '\n') { 57 rhbufi = 0; 58 *flagp = GPR; 59 return 0; 60 } else if (extract_subst_template() == NULL) 61 return ERR; 62 else if (*ibufp == '\n') { 63 *flagp = GPR; 64 return 0; 65 } else if (*ibufp == delimiter) 66 ibufp++; 67 if ('1' <= *ibufp && *ibufp <= '9') { 68 STRTOI(*np, ibufp); 69 return 0; 70 } else if (*ibufp == 'g') { 71 ibufp++; 72 *flagp = GSG; 73 return 0; 74 } 75 return 0; 76} 77 78 79/* extract_subst_template: return pointer to copy of substitution template 80 in the command buffer */ 81static char * 82extract_subst_template(void) 83{ 84 int n = 0; 85 int i = 0; 86 char c; 87 char delimiter = *ibufp++; 88 89 if (*ibufp == '%' && *(ibufp + 1) == delimiter) { 90 ibufp++; 91 if (!rhbuf) 92 seterrmsg("no previous substitution"); 93 return rhbuf; 94 } 95 while (*ibufp != delimiter) { 96 REALLOC(rhbuf, rhbufsz, i + 2, NULL); 97 if ((c = rhbuf[i++] = *ibufp++) == '\n' && *ibufp == '\0') { 98 i--, ibufp--; 99 break; 100 } else if (c != '\\') 101 ; 102 else if ((rhbuf[i++] = *ibufp++) != '\n') 103 ; 104 else if (!isglobal) { 105 while ((n = get_tty_line()) == 0 || 106 (n > 0 && ibuf[n - 1] != '\n')) 107 clearerr(stdin); 108 if (n < 0) 109 return NULL; 110 } 111 } 112 REALLOC(rhbuf, rhbufsz, i + 1, NULL); 113 rhbuf[rhbufi = i] = '\0'; 114 return rhbuf; 115} 116 117 118static char *rbuf; /* substitute_matching_text buffer */ 119static int rbufsz; /* substitute_matching_text buffer size */ 120 121/* search_and_replace: for each line in a range, change text matching a pattern 122 according to a substitution template; return status */ 123int 124search_and_replace(regex_t *pat, int gflag, int kth) 125{ 126 undo_t *up; 127 char *txt; 128 char *eot; 129 int lc; 130 int xa = current_addr; 131 int nsubs = 0; 132 line_t *lp; 133 int len; 134 135 current_addr = first_addr - 1; 136 for (lc = 0; lc <= second_addr - first_addr; lc++) { 137 lp = get_addressed_line_node(++current_addr); 138 if ((len = substitute_matching_text(pat, lp, gflag, kth)) < 0) 139 return ERR; 140 else if (len) { 141 up = NULL; 142 if (delete_lines(current_addr, current_addr) < 0) 143 return ERR; 144 txt = rbuf; 145 eot = rbuf + len; 146 SPL1(); 147 do { 148 if ((txt = put_sbuf_line(txt)) == NULL) { 149 SPL0(); 150 return ERR; 151 } else if (up) 152 up->t = get_addressed_line_node(current_addr); 153 else if ((up = push_undo_stack(UADD, 154 current_addr, current_addr)) == NULL) { 155 SPL0(); 156 return ERR; 157 } 158 } while (txt != eot); 159 SPL0(); 160 nsubs++; 161 xa = current_addr; 162 } 163 } 164 current_addr = xa; 165 if (nsubs == 0 && !(gflag & GLB)) { 166 seterrmsg("no match"); 167 return ERR; 168 } else if ((gflag & (GPR | GLS | GNP)) && 169 display_lines(current_addr, current_addr, gflag) < 0) 170 return ERR; 171 return 0; 172} 173 174 175/* substitute_matching_text: replace text matched by a pattern according to 176 a substitution template; return length of rbuf if changed, 0 if unchanged, or 177 ERR on error */ 178static int 179substitute_matching_text(regex_t *pat, line_t *lp, int gflag, int kth) 180{ 181 int off = 0; 182 int changed = 0; 183 int matchno = 0; 184 int i = 0; 185 int nempty = -1; 186 regmatch_t rm[SE_MAX]; 187 char *txt; 188 char *eot, *eom; 189 190 if ((eom = txt = get_sbuf_line(lp)) == NULL) 191 return ERR; 192 if (isbinary) 193 NUL_TO_NEWLINE(txt, lp->len); 194 eot = txt + lp->len; 195 if (!regexec(pat, txt, SE_MAX, rm, 0)) { 196 do { 197/* Don't do a 0-length match directly after a non-0-length */ 198 if (rm[0].rm_eo == nempty) { 199 rm[0].rm_so++; 200 rm[0].rm_eo = lp->len; 201 continue; 202 } 203 if (!kth || kth == ++matchno) { 204 changed = 1; 205 i = rm[0].rm_so - (eom - txt); 206 REALLOC(rbuf, rbufsz, off + i, ERR); 207 if (isbinary) 208 NEWLINE_TO_NUL(eom, 209 rm[0].rm_eo - (eom - txt)); 210 memcpy(rbuf + off, eom, i); 211 off += i; 212 if ((off = apply_subst_template(txt, rm, off, 213 pat->re_nsub)) < 0) 214 return ERR; 215 eom = txt + rm[0].rm_eo; 216 if (kth) 217 break; 218 } 219 if (rm[0].rm_so == rm[0].rm_eo) 220 rm[0].rm_so = rm[0].rm_eo + 1; 221 else 222 nempty = rm[0].rm_so = rm[0].rm_eo; 223 rm[0].rm_eo = lp->len; 224 } while (rm[0].rm_so < lp->len && (gflag & GSG || kth) && 225 !regexec(pat, txt, SE_MAX, rm, REG_STARTEND | REG_NOTBOL)); 226 i = eot - eom; 227 REALLOC(rbuf, rbufsz, off + i + 2, ERR); 228 if (isbinary) 229 NEWLINE_TO_NUL(eom, i); 230 memcpy(rbuf + off, eom, i); 231 memcpy(rbuf + off + i, "\n", 2); 232 } 233 return changed ? off + i + 1 : 0; 234} 235 236 237/* apply_subst_template: modify text according to a substitution template; 238 return offset to end of modified text */ 239static int 240apply_subst_template(char *boln, regmatch_t *rm, int off, int re_nsub) 241{ 242 int j = 0; 243 int k = 0; 244 int n; 245 char *sub = rhbuf; 246 247 for (; sub - rhbuf < rhbufi; sub++) 248 if (*sub == '&') { 249 j = rm[0].rm_so; 250 k = rm[0].rm_eo; 251 REALLOC(rbuf, rbufsz, off + k - j, ERR); 252 while (j < k) 253 rbuf[off++] = boln[j++]; 254 } else if (*sub == '\\' && '1' <= *++sub && *sub <= '9' && 255 (n = *sub - '0') <= re_nsub) { 256 j = rm[n].rm_so; 257 k = rm[n].rm_eo; 258 REALLOC(rbuf, rbufsz, off + k - j, ERR); 259 while (j < k) 260 rbuf[off++] = boln[j++]; 261 } else { 262 REALLOC(rbuf, rbufsz, off + 1, ERR); 263 rbuf[off++] = *sub; 264 } 265 REALLOC(rbuf, rbufsz, off + 1, ERR); 266 rbuf[off] = '\0'; 267 return off; 268} 269