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