add pgn-extract 22.11

pgn-extract/lines.c

@@ -0,0 +1,73 @@
+/*
+ *  This file is part of pgn-extract: a Portable Game Notation (PGN) extractor.
+ *  Copyright (C) 1994-2022 David J. Barnes
+ *
+ *  pgn-extract is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  pgn-extract is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with pgn-extract. If not, see <http://www.gnu.org/licenses/>.
+ *
+ *  David J. Barnes may be contacted as d.j.barnes@kent.ac.uk
+ *  https://www.cs.kent.ac.uk/people/staff/djb/
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include "bool.h"
+#include "mymalloc.h"
+#include "lines.h"
+
+/* Define a character that may be used to comment a line in, e.g.
+ * the variations files.
+ * Use the PGN escape mechanism character, for consistency.
+ */
+#define COMMENT_CHAR '%'
+
+/* Return TRUE if line contains a non-space character, but
+ * is not a comment line.
+ */
+Boolean
+non_blank_line(const char *line)
+{
+    Boolean blank = TRUE;
+
+    if (line != NULL) {
+        if (comment_line(line)) {
+            /* Comment lines count as blanks. */
+        }
+        else {
+            while (blank && (*line != '\0')) {
+                if (!isspace((int) *line)) {
+                    blank = FALSE;
+                }
+                else {
+                    line++;
+                }
+            }
+        }
+    }
+    return !blank;
+}
+
+Boolean
+blank_line(const char *line)
+{
+    return !non_blank_line(line);
+}
+
+/* Should the given line be regarded as a comment line? */
+Boolean
+comment_line(const char *line)
+{
+    return *line == COMMENT_CHAR;
+}