sub.c revision 90109
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 29#ifndef lint 30static const char rcsid[] = 31 "$FreeBSD: head/bin/ed/sub.c 90109 2002-02-02 06:36:49Z imp $"; 32#endif /* not lint */ 33 34#include "ed.h" 35 36 37char *rhbuf; /* rhs substitution buffer */ 38int rhbufsz; /* rhs substitution buffer size */ 39int rhbufi; /* rhs substitution buffer index */ 40 41/* extract_subst_tail: extract substitution tail from the command buffer */ 42int 43extract_subst_tail(int *flagp, long *np) 44{ 45 char delimiter; 46 47 *flagp = *np = 0; 48 if ((delimiter = *ibufp) == '\n') { 49 rhbufi = 0; 50 *flagp = GPR; 51 return 0; 52 } else if (extract_subst_template() == NULL) 53 return ERR; 54 else if (*ibufp == '\n') { 55 *flagp = GPR; 56 return 0; 57 } else if (*ibufp == delimiter) 58 ibufp++; 59 if ('1' <= *ibufp && *ibufp <= '9') { 60 STRTOL(*np, ibufp); 61 return 0; 62 } else if (*ibufp == 'g') { 63 ibufp++; 64 *flagp = GSG; 65 return 0; 66 } 67 return 0; 68} 69 70 71/* extract_subst_template: return pointer to copy of substitution template 72 in the command buffer */ 73char * 74extract_subst_template(void) 75{ 76 int n = 0; 77 int i = 0; 78 char c; 79 char delimiter = *ibufp++; 80 81 if (*ibufp == '%' && *(ibufp + 1) == delimiter) { 82 ibufp++; 83 if (!rhbuf) 84 errmsg = "no previous substitution"; 85 return rhbuf; 86 } 87 while (*ibufp != delimiter) { 88 REALLOC(rhbuf, rhbufsz, i + 2, NULL); 89 if ((c = rhbuf[i++] = *ibufp++) == '\n' && *ibufp == '\0') { 90 i--, ibufp--; 91 break; 92 } else if (c != '\\') 93 ; 94 else if ((rhbuf[i++] = *ibufp++) != '\n') 95 ; 96 else if (!isglobal) { 97 while ((n = get_tty_line()) == 0 || 98 (n > 0 && ibuf[n - 1] != '\n')) 99 clearerr(stdin); 100 if (n < 0) 101 return NULL; 102 } 103 } 104 REALLOC(rhbuf, rhbufsz, i + 1, NULL); 105 rhbuf[rhbufi = i] = '\0'; 106 return rhbuf; 107} 108 109 110char *rbuf; /* substitute_matching_text buffer */ 111int rbufsz; /* substitute_matching_text buffer size */ 112 113/* search_and_replace: for each line in a range, change text matching a pattern 114 according to a substitution template; return status */ 115int 116search_and_replace(pattern_t *pat, int gflag, int kth) 117{ 118 undo_t *up; 119 const char *txt; 120 const char *eot; 121 long lc; 122 long xa = current_addr; 123 int nsubs = 0; 124 line_t *lp; 125 int len; 126 127 current_addr = first_addr - 1; 128 for (lc = 0; lc <= second_addr - first_addr; lc++) { 129 lp = get_addressed_line_node(++current_addr); 130 if ((len = substitute_matching_text(pat, lp, gflag, kth)) < 0) 131 return ERR; 132 else if (len) { 133 up = NULL; 134 if (delete_lines(current_addr, current_addr) < 0) 135 return ERR; 136 txt = rbuf; 137 eot = rbuf + len; 138 SPL1(); 139 do { 140 if ((txt = put_sbuf_line(txt)) == NULL) { 141 SPL0(); 142 return ERR; 143 } else if (up) 144 up->t = get_addressed_line_node(current_addr); 145 else if ((up = push_undo_stack(UADD, 146 current_addr, current_addr)) == NULL) { 147 SPL0(); 148 return ERR; 149 } 150 } while (txt != eot); 151 SPL0(); 152 nsubs++; 153 xa = current_addr; 154 } 155 } 156 current_addr = xa; 157 if (nsubs == 0 && !(gflag & GLB)) { 158 errmsg = "no match"; 159 return ERR; 160 } else if ((gflag & (GPR | GLS | GNP)) && 161 display_lines(current_addr, current_addr, gflag) < 0) 162 return ERR; 163 return 0; 164} 165 166 167/* substitute_matching_text: replace text matched by a pattern according to 168 a substitution template; return pointer to the modified text */ 169int 170substitute_matching_text(pattern_t *pat, line_t *lp, int gflag, int kth) 171{ 172 int off = 0; 173 int changed = 0; 174 int matchno = 0; 175 int i = 0; 176 regmatch_t rm[SE_MAX]; 177 char *txt; 178 char *eot; 179 180 if ((txt = get_sbuf_line(lp)) == NULL) 181 return ERR; 182 if (isbinary) 183 NUL_TO_NEWLINE(txt, lp->len); 184 eot = txt + lp->len; 185 if (!regexec(pat, txt, SE_MAX, rm, 0)) { 186 do { 187 if (!kth || kth == ++matchno) { 188 changed++; 189 i = rm[0].rm_so; 190 REALLOC(rbuf, rbufsz, off + i, ERR); 191 if (isbinary) 192 NEWLINE_TO_NUL(txt, rm[0].rm_eo); 193 memcpy(rbuf + off, txt, i); 194 off += i; 195 if ((off = apply_subst_template(txt, rm, off, 196 pat->re_nsub)) < 0) 197 return ERR; 198 } else { 199 i = rm[0].rm_eo; 200 REALLOC(rbuf, rbufsz, off + i, ERR); 201 if (isbinary) 202 NEWLINE_TO_NUL(txt, i); 203 memcpy(rbuf + off, txt, i); 204 off += i; 205 } 206 txt += rm[0].rm_eo; 207 } while (*txt && 208 (!changed || ((gflag & GSG) && rm[0].rm_eo)) && 209 !regexec(pat, txt, SE_MAX, rm, REG_NOTBOL)); 210 i = eot - txt; 211 REALLOC(rbuf, rbufsz, off + i + 2, ERR); 212 if (i > 0 && !rm[0].rm_eo && (gflag & GSG)) { 213 errmsg = "infinite substitution loop"; 214 return ERR; 215 } 216 if (isbinary) 217 NEWLINE_TO_NUL(txt, i); 218 memcpy(rbuf + off, txt, i); 219 memcpy(rbuf + off + i, "\n", 2); 220 } 221 return changed ? off + i + 1 : 0; 222} 223 224 225/* apply_subst_template: modify text according to a substitution template; 226 return offset to end of modified text */ 227int 228apply_subst_template(const char *boln, regmatch_t *rm, int off, int re_nsub) 229{ 230 int j = 0; 231 int k = 0; 232 int n; 233 char *sub = rhbuf; 234 235 for (; sub - rhbuf < rhbufi; sub++) 236 if (*sub == '&') { 237 j = rm[0].rm_so; 238 k = rm[0].rm_eo; 239 REALLOC(rbuf, rbufsz, off + k - j, ERR); 240 while (j < k) 241 rbuf[off++] = boln[j++]; 242 } else if (*sub == '\\' && '1' <= *++sub && *sub <= '9' && 243 (n = *sub - '0') <= re_nsub) { 244 j = rm[n].rm_so; 245 k = rm[n].rm_eo; 246 REALLOC(rbuf, rbufsz, off + k - j, ERR); 247 while (j < k) 248 rbuf[off++] = boln[j++]; 249 } else { 250 REALLOC(rbuf, rbufsz, off + 1, ERR); 251 rbuf[off++] = *sub; 252 } 253 REALLOC(rbuf, rbufsz, off + 1, ERR); 254 rbuf[off] = '\0'; 255 return off; 256} 257