1 /* 2 * Copyright (C) 1984-2012 Mark Nudelman 3 * Modified for use with illumos by Garrett D'Amore. 4 * Copyright 2014 Garrett D'Amore <garrett@damore.org> 5 * 6 * You may distribute under the terms of either the GNU General Public 7 * License or the Less License, as specified in the README file. 8 * 9 * For more information, see the README file. 10 */ 11 12 /* 13 * Routines to perform bracket matching functions. 14 */ 15 16 #include "less.h" 17 #include "position.h" 18 19 /* 20 * Try to match the n-th open bracket 21 * which appears in the top displayed line (forwdir), 22 * or the n-th close bracket 23 * which appears in the bottom displayed line (!forwdir). 24 * The characters which serve as "open bracket" and 25 * "close bracket" are given. 26 */ 27 void 28 match_brac(int obrac, int cbrac, int forwdir, int n) 29 { 30 int c; 31 int nest; 32 off_t pos; 33 int (*chget)(void); 34 35 /* 36 * Seek to the line containing the open bracket. 37 * This is either the top or bottom line on the screen, 38 * depending on the type of bracket. 39 */ 40 pos = position((forwdir) ? TOP : BOTTOM); 41 if (pos == -1 || ch_seek(pos)) { 42 if (forwdir) 43 error("Nothing in top line", NULL); 44 else 45 error("Nothing in bottom line", NULL); 46 return; 47 } 48 49 /* 50 * Look thru the line to find the open bracket to match. 51 */ 52 do { 53 if ((c = ch_forw_get()) == '\n' || c == EOI) { 54 if (forwdir) 55 error("No bracket in top line", NULL); 56 else 57 error("No bracket in bottom line", NULL); 58 return; 59 } 60 } while (c != obrac || --n > 0); 61 62 /* 63 * Position the file just "after" the open bracket 64 * (in the direction in which we will be searching). 65 * If searching forward, we are already after the bracket. 66 * If searching backward, skip back over the open bracket. 67 */ 68 if (!forwdir) 69 (void) ch_back_get(); 70 71 /* 72 * Search the file for the matching bracket. 73 */ 74 chget = (forwdir) ? ch_forw_get : ch_back_get; 75 nest = 0; 76 while ((c = (*chget)()) != EOI) { 77 if (c == obrac) { 78 nest++; 79 } else if (c == cbrac && --nest < 0) { 80 /* 81 * Found the matching bracket. 82 * If searching backward, put it on the top line. 83 * If searching forward, put it on the bottom line. 84 */ 85 jump_line_loc(ch_tell(), forwdir ? -1 : 1); 86 return; 87 } 88 } 89 error("No matching bracket", NULL); 90 } 91