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authorLorry Tar Creator <lorry-tar-importer@baserock.org>2012-07-21 20:40:00 +0000
committerLorry <lorry@roadtrain.codethink.co.uk>2012-09-24 16:52:48 +0000
commit09a405d8f652b56944c93ebf5c673cdfe5319b04 (patch)
tree9cc4518b0a21096735b20ac3204a6fa032f1c566 /brac.c
downloadless-master.tar.gz
Imported from /srv/lorry/lorry-area/less/less-451.tar.gz.HEADless-451masterbaserock/morph
Diffstat (limited to 'brac.c')
-rwxr-xr-xbrac.c100
1 files changed, 100 insertions, 0 deletions
diff --git a/brac.c b/brac.c
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+/*
+ * Copyright (C) 1984-2012 Mark Nudelman
+ *
+ * You may distribute under the terms of either the GNU General Public
+ * License or the Less License, as specified in the README file.
+ *
+ * For more information, see the README file.
+ */
+
+
+/*
+ * Routines to perform bracket matching functions.
+ */
+
+#include "less.h"
+#include "position.h"
+
+/*
+ * Try to match the n-th open bracket
+ * which appears in the top displayed line (forwdir),
+ * or the n-th close bracket
+ * which appears in the bottom displayed line (!forwdir).
+ * The characters which serve as "open bracket" and
+ * "close bracket" are given.
+ */
+ public void
+match_brac(obrac, cbrac, forwdir, n)
+ register int obrac;
+ register int cbrac;
+ int forwdir;
+ int n;
+{
+ register int c;
+ register int nest;
+ POSITION pos;
+ int (*chget)();
+
+ extern int ch_forw_get(), ch_back_get();
+
+ /*
+ * Seek to the line containing the open bracket.
+ * This is either the top or bottom line on the screen,
+ * depending on the type of bracket.
+ */
+ pos = position((forwdir) ? TOP : BOTTOM);
+ if (pos == NULL_POSITION || ch_seek(pos))
+ {
+ if (forwdir)
+ error("Nothing in top line", NULL_PARG);
+ else
+ error("Nothing in bottom line", NULL_PARG);
+ return;
+ }
+
+ /*
+ * Look thru the line to find the open bracket to match.
+ */
+ do
+ {
+ if ((c = ch_forw_get()) == '\n' || c == EOI)
+ {
+ if (forwdir)
+ error("No bracket in top line", NULL_PARG);
+ else
+ error("No bracket in bottom line", NULL_PARG);
+ return;
+ }
+ } while (c != obrac || --n > 0);
+
+ /*
+ * Position the file just "after" the open bracket
+ * (in the direction in which we will be searching).
+ * If searching forward, we are already after the bracket.
+ * If searching backward, skip back over the open bracket.
+ */
+ if (!forwdir)
+ (void) ch_back_get();
+
+ /*
+ * Search the file for the matching bracket.
+ */
+ chget = (forwdir) ? ch_forw_get : ch_back_get;
+ nest = 0;
+ while ((c = (*chget)()) != EOI)
+ {
+ if (c == obrac)
+ nest++;
+ else if (c == cbrac && --nest < 0)
+ {
+ /*
+ * Found the matching bracket.
+ * If searching backward, put it on the top line.
+ * If searching forward, put it on the bottom line.
+ */
+ jump_line_loc(ch_tell(), forwdir ? -1 : 1);
+ return;
+ }
+ }
+ error("No matching bracket", NULL_PARG);
+}