bin/ed/sub.c

   1 /*      $NetBSD: sub.c,v 1.7 2014/03/23 05:06:42 dholland Exp $ */
   2
   3 /* sub.c: This file contains the substitution routines for the ed
   4    line editor */
   5 /*-
   6  * Copyright (c) 1993 Andrew Moore, Talke Studio.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  28  * SUCH DAMAGE.
  29  */
  30
  31 #include <sys/cdefs.h>
  32 #ifndef lint
  33 #if 0
  34 static char *rcsid = "@(#)sub.c,v 1.1 1994/02/01 00:34:44 alm Exp";
  35 #else
  36 __RCSID("$NetBSD: sub.c,v 1.7 2014/03/23 05:06:42 dholland Exp $");
  37 #endif
  38 #endif /* not lint */
  39
  40 #include "ed.h"
  41
  42
  43 char *rhbuf;                    /* rhs substitution buffer */
  44 int rhbufsz;                    /* rhs substitution buffer size */
  45 int rhbufi;                     /* rhs substitution buffer index */
  46
  47 /* extract_subst_tail: extract substitution tail from the command buffer */
  48 int
  49 extract_subst_tail(int *flagp, long *np)
  50 {
  51         char delimiter;
  52
  53         *flagp = *np = 0;
  54         if ((delimiter = *ibufp) == '\n') {
  55                 rhbufi = 0;
  56                 *flagp = GPR;
  57                 return 0;
  58         } else if (extract_subst_template() == NULL)
  59                 return  ERR;
  60         else if (*ibufp == '\n') {
  61                 *flagp = GPR;
  62                 return 0;
  63         } else if (*ibufp == delimiter)
  64                 ibufp++;
  65         if ('1' <= *ibufp && *ibufp <= '9') {
  66                 STRTOL(*np, ibufp);
  67                 return 0;
  68         } else if (*ibufp == 'g') {
  69                 ibufp++;
  70                 *flagp = GSG;
  71                 return 0;
  72         }
  73         return 0;
  74 }
  75
  76
  77 /* extract_subst_template: return pointer to copy of substitution template
  78    in the command buffer */
  79 char *
  80 extract_subst_template(void)
  81 {
  82         int n = 0;
  83         int i = 0;
  84         char c;
  85         char delimiter = *ibufp++;
  86
  87         if (*ibufp == '%' && *(ibufp + 1) == delimiter) {
  88                 ibufp++;
  89                 if (!rhbuf) {
  90                         seterrmsg("no previous substitution");
  91                 }
  92                 return rhbuf;
  93         }
  94         while (*ibufp != delimiter) {
  95                 REALLOC(rhbuf, rhbufsz, i + 2, NULL);
  96                 if ((c = rhbuf[i++] = *ibufp++) == '\n' && *ibufp == '\0') {
  97                         i--, ibufp--;
  98                         break;
  99                 } else if (c != '\\')
 100                         ;
 101                 else if ((rhbuf[i++] = *ibufp++) != '\n')
 102                         ;
 103                 else if (!isglobal) {
 104                         while ((n = get_tty_line()) == 0 ||
 105                             (n > 0 && ibuf[n - 1] != '\n'))
 106                                 clearerr(stdin);
 107                         if (n < 0)
 108                                 return NULL;
 109                 }
 110         }
 111         REALLOC(rhbuf, rhbufsz, i + 1, NULL);
 112         rhbuf[rhbufi = i] = '\0';
 113         return  rhbuf;
 114 }
 115
 116
 117 char *rbuf;                     /* substitute_matching_text buffer */
 118 int rbufsz;                     /* substitute_matching_text buffer size */
 119
 120 /* search_and_replace: for each line in a range, change text matching a pattern
 121    according to a substitution template; return status  */
 122 int
 123 search_and_replace(pattern_t *pat, int gflag, int kth)
 124 {
 125         undo_t *up;
 126         char *txt;
 127         char *eot;
 128         long lc;
 129         long xa = current_addr;
 130         int nsubs = 0;
 131         line_t *lp;
 132         int len;
 133
 134         current_addr = first_addr - 1;
 135         for (lc = 0; lc <= second_addr - first_addr; lc++) {
 136                 lp = get_addressed_line_node(++current_addr);
 137                 if ((len = substitute_matching_text(pat, lp, gflag, kth)) < 0)
 138                         return ERR;
 139                 else if (len) {
 140                         up = NULL;
 141                         if (delete_lines(current_addr, current_addr) < 0)
 142                                 return ERR;
 143                         txt = rbuf;
 144                         eot = rbuf + len;
 145                         SPL1();
 146                         do {
 147                                 if ((txt = put_sbuf_line(txt)) == NULL) {
 148                                         SPL0();
 149                                         return ERR;
 150                                 } else if (up)
 151                                         up->t = get_addressed_line_node(current_addr);
 152                                 else if ((up = push_undo_stack(UADD,
 153                                     current_addr, current_addr)) == NULL) {
 154                                         SPL0();
 155                                         return ERR;
 156                                 }
 157                         } while (txt != eot);
 158                         SPL0();
 159                         nsubs++;
 160                         xa = current_addr;
 161                 }
 162         }
 163         current_addr = xa;
 164         if  (nsubs == 0 && !(gflag & GLB)) {
 165                 seterrmsg("no match");
 166                 return ERR;
 167         } else if ((gflag & (GPR | GLS | GNP)) &&
 168             display_lines(current_addr, current_addr, gflag) < 0)
 169                 return ERR;
 170         return 0;
 171 }
 172
 173
 174 /* substitute_matching_text: replace text matched by a pattern according to
 175    a substitution template; return pointer to the modified text */
 176 int
 177 substitute_matching_text(pattern_t *pat, line_t *lp, int gflag, int kth)
 178 {
 179         int off = 0;
 180         int changed = 0;
 181         int matchno = 0;
 182         int i = 0;
 183         regmatch_t rm[SE_MAX];
 184         char *txt;
 185         char *eot;
 186
 187         if ((txt = get_sbuf_line(lp)) == NULL)
 188                 return ERR;
 189         if (isbinary)
 190                 NUL_TO_NEWLINE(txt, lp->len);
 191         eot = txt + lp->len;
 192         if (!regexec(pat, txt, SE_MAX, rm, 0)) {
 193                 do {
 194                         if (!kth || kth == ++matchno) {
 195                                 changed++;
 196                                 i = rm[0].rm_so;
 197                                 REALLOC(rbuf, rbufsz, off + i, ERR);
 198                                 if (isbinary)
 199                                         NEWLINE_TO_NUL(txt, rm[0].rm_eo);
 200                                 memcpy(rbuf + off, txt, i);
 201                                 off += i;
 202                                 if ((off = apply_subst_template(txt, rm, off,
 203                                     pat->re_nsub)) < 0)
 204                                         return ERR;
 205                         } else {
 206                                 i = rm[0].rm_eo;
 207                                 REALLOC(rbuf, rbufsz, off + i, ERR);
 208                                 if (isbinary)
 209                                         NEWLINE_TO_NUL(txt, i);
 210                                 memcpy(rbuf + off, txt, i);
 211                                 off += i;
 212                         }
 213                         txt += rm[0].rm_eo;
 214                 } while (*txt && (!changed || ((gflag & GSG) && rm[0].rm_eo))
 215                     && !regexec(pat, txt, SE_MAX, rm, REG_NOTBOL));
 216                 i = eot - txt;
 217                 REALLOC(rbuf, rbufsz, off + i + 2, ERR);
 218                 if (i > 0 && !rm[0].rm_eo && (gflag & GSG)) {
 219                         seterrmsg("infinite substitution loop");
 220                         return  ERR;
 221                 }
 222                 if (isbinary)
 223                         NEWLINE_TO_NUL(txt, i);
 224                 memcpy(rbuf + off, txt, i);
 225                 memcpy(rbuf + off + i, "\n", 2);
 226         }
 227         return changed ? off + i + 1 : 0;
 228 }
 229
 230
 231 /* apply_subst_template: modify text according to a substitution template;
 232    return offset to end of modified text */
 233 int
 234 apply_subst_template(char *boln, regmatch_t *rm, int off, int re_nsub)
 235 {
 236         int j = 0;
 237         int k = 0;
 238         int n;
 239         char *sub = rhbuf;
 240
 241         for (; sub - rhbuf < rhbufi; sub++)
 242                 if (*sub == '&') {
 243                         j = rm[0].rm_so;
 244                         k = rm[0].rm_eo;
 245                         REALLOC(rbuf, rbufsz, off + k - j, ERR);
 246                         while (j < k)
 247                                 rbuf[off++] = boln[j++];
 248                 } else if (*sub == '\\' && '1' <= *++sub && *sub <= '9' &&
 249                     (n = *sub - '0') <= re_nsub) {
 250                         j = rm[n].rm_so;
 251                         k = rm[n].rm_eo;
 252                         REALLOC(rbuf, rbufsz, off + k - j, ERR);
 253                         while (j < k)
 254                                 rbuf[off++] = boln[j++];
 255                 } else {
 256                         REALLOC(rbuf, rbufsz, off + 1, ERR);
 257                         rbuf[off++] = *sub;
 258                 }
 259         REALLOC(rbuf, rbufsz, off + 1, ERR);
 260         rbuf[off] = '\0';
 261         return off;
 262 }