1 /* sub.c: This file contains the substitution routines for the ed 2 line editor */ 3 /*- 4 * Copyright (c) 1993 Andrew Moore, Talke Studio. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * @(#)sub.c,v 1.1 1994/02/01 00:34:44 alm Exp 29 * $FreeBSD: head/bin/ed/sub.c 241720 2012-10-19 05:43:38Z ed $ 30 */ 31 32 #include "ed.h" 33 34 35 static char *rhbuf; /* rhs substitution buffer */ 36 static int rhbufsz; /* rhs substitution buffer size */ 37 static int rhbufi; /* rhs substitution buffer index */ 38 39 /* extract_subst_tail: extract substitution tail from the command buffer */ 40 int 41 extract_subst_tail(int *flagp, long *np) 42 { 43 char delimiter; 44 45 *flagp = *np = 0; 46 if ((delimiter = *ibufp) == '\n') { 47 rhbufi = 0; 48 *flagp = GPR; 49 return 0; 50 } else if (extract_subst_template() == NULL) 51 return ERR; 52 else if (*ibufp == '\n') { 53 *flagp = GPR; 54 return 0; 55 } else if (*ibufp == delimiter) 56 ibufp++; 57 if ('1' <= *ibufp && *ibufp <= '9') { 58 STRTOL(*np, ibufp); 59 return 0; 60 } else if (*ibufp == 'g') { 61 ibufp++; 62 *flagp = GSG; 63 return 0; 64 } 65 return 0; 66 } 67 68 69 /* extract_subst_template: return pointer to copy of substitution template 70 in the command buffer */ 71 char * 72 extract_subst_template(void) 73 { 74 int n = 0; 75 int i = 0; 76 char c; 77 char delimiter = *ibufp++; 78 79 if (*ibufp == '%' && *(ibufp + 1) == delimiter) { 80 ibufp++; 81 if (!rhbuf) 82 errmsg = "no previous substitution"; 83 return rhbuf; 84 } 85 while (*ibufp != delimiter) { 86 REALLOC(rhbuf, rhbufsz, i + 2, NULL); 87 if ((c = rhbuf[i++] = *ibufp++) == '\n' && *ibufp == '\0') { 88 i--, ibufp--; 89 break; 90 } else if (c != '\\') 91 ; 92 else if ((rhbuf[i++] = *ibufp++) != '\n') 93 ; 94 else if (!isglobal) { 95 while ((n = get_tty_line()) == 0 || 96 (n > 0 && ibuf[n - 1] != '\n')) 97 clearerr(stdin); 98 if (n < 0) 99 return NULL; 100 } 101 } 102 REALLOC(rhbuf, rhbufsz, i + 1, NULL); 103 rhbuf[rhbufi = i] = '\0'; 104 return rhbuf; 105 } 106 107 108 static char *rbuf; /* substitute_matching_text buffer */ 109 static int rbufsz; /* substitute_matching_text buffer size */ 110 111 /* search_and_replace: for each line in a range, change text matching a pattern 112 according to a substitution template; return status */ 113 int 114 search_and_replace(pattern_t *pat, int gflag, int kth) 115 { 116 undo_t *up; 117 const char *txt; 118 const char *eot; 119 long lc; 120 long xa = current_addr; 121 int nsubs = 0; 122 line_t *lp; 123 int len; 124 125 current_addr = first_addr - 1; 126 for (lc = 0; lc <= second_addr - first_addr; lc++) { 127 lp = get_addressed_line_node(++current_addr); 128 if ((len = substitute_matching_text(pat, lp, gflag, kth)) < 0) 129 return ERR; 130 else if (len) { 131 up = NULL; 132 if (delete_lines(current_addr, current_addr) < 0) 133 return ERR; 134 txt = rbuf; 135 eot = rbuf + len; 136 SPL1(); 137 do { 138 if ((txt = put_sbuf_line(txt)) == NULL) { 139 SPL0(); 140 return ERR; 141 } else if (up) 142 up->t = get_addressed_line_node(current_addr); 143 else if ((up = push_undo_stack(UADD, 144 current_addr, current_addr)) == NULL) { 145 SPL0(); 146 return ERR; 147 } 148 } while (txt != eot); 149 SPL0(); 150 nsubs++; 151 xa = current_addr; 152 } 153 } 154 current_addr = xa; 155 if (nsubs == 0 && !(gflag & GLB)) { 156 errmsg = "no match"; 157 return ERR; 158 } else if ((gflag & (GPR | GLS | GNP)) && 159 display_lines(current_addr, current_addr, gflag) < 0) 160 return ERR; 161 return 0; 162 } 163 164 165 /* substitute_matching_text: replace text matched by a pattern according to 166 a substitution template; return pointer to the modified text */ 167 int 168 substitute_matching_text(pattern_t *pat, line_t *lp, int gflag, int kth) 169 { 170 int off = 0; 171 int changed = 0; 172 int matchno = 0; 173 int i = 0; 174 regmatch_t rm[SE_MAX]; 175 char *txt; 176 char *eot; 177 178 if ((txt = get_sbuf_line(lp)) == NULL) 179 return ERR; 180 if (isbinary) 181 NUL_TO_NEWLINE(txt, lp->len); 182 eot = txt + lp->len; 183 if (!regexec(pat, txt, SE_MAX, rm, 0)) { 184 do { 185 if (!kth || kth == ++matchno) { 186 changed++; 187 i = rm[0].rm_so; 188 REALLOC(rbuf, rbufsz, off + i, ERR); 189 if (isbinary) 190 NEWLINE_TO_NUL(txt, rm[0].rm_eo); 191 memcpy(rbuf + off, txt, i); 192 off += i; 193 if ((off = apply_subst_template(txt, rm, off, 194 pat->re_nsub)) < 0) 195 return ERR; 196 } else { 197 i = rm[0].rm_eo; 198 REALLOC(rbuf, rbufsz, off + i, ERR); 199 if (isbinary) 200 NEWLINE_TO_NUL(txt, i); 201 memcpy(rbuf + off, txt, i); 202 off += i; 203 } 204 txt += rm[0].rm_eo; 205 } while (*txt && 206 (!changed || ((gflag & GSG) && rm[0].rm_eo)) && 207 !regexec(pat, txt, SE_MAX, rm, REG_NOTBOL)); 208 i = eot - txt; 209 REALLOC(rbuf, rbufsz, off + i + 2, ERR); 210 if (i > 0 && !rm[0].rm_eo && (gflag & GSG)) { 211 errmsg = "infinite substitution loop"; 212 return ERR; 213 } 214 if (isbinary) 215 NEWLINE_TO_NUL(txt, i); 216 memcpy(rbuf + off, txt, i); 217 memcpy(rbuf + off + i, "\n", 2); 218 } 219 return changed ? off + i + 1 : 0; 220 } 221 222 223 /* apply_subst_template: modify text according to a substitution template; 224 return offset to end of modified text */ 225 int 226 apply_subst_template(const char *boln, regmatch_t *rm, int off, int re_nsub) 227 { 228 int j = 0; 229 int k = 0; 230 int n; 231 char *sub = rhbuf; 232 233 for (; sub - rhbuf < rhbufi; sub++) 234 if (*sub == '&') { 235 j = rm[0].rm_so; 236 k = rm[0].rm_eo; 237 REALLOC(rbuf, rbufsz, off + k - j, ERR); 238 while (j < k) 239 rbuf[off++] = boln[j++]; 240 } else if (*sub == '\\' && '1' <= *++sub && *sub <= '9' && 241 (n = *sub - '0') <= re_nsub) { 242 j = rm[n].rm_so; 243 k = rm[n].rm_eo; 244 REALLOC(rbuf, rbufsz, off + k - j, ERR); 245 while (j < k) 246 rbuf[off++] = boln[j++]; 247 } else { 248 REALLOC(rbuf, rbufsz, off + 1, ERR); 249 rbuf[off++] = *sub; 250 } 251 REALLOC(rbuf, rbufsz, off + 1, ERR); 252 rbuf[off] = '\0'; 253 return off; 254 } 255