regex: Add support for emacs and grep types

1 files changed, 62 insertions, 0 deletions

diff --git a/regex.c b/regex.c
new file mode 100644
index 0000000..f8bd833
--- /dev/null
+++ b/regex.c
@@ -0,0 +1,62 @@
+/****************************************************************************
+ * bfs                                                                      *
+ * Copyright (C) 2022 Tavian Barnes <tavianator@tavianator.com>             *
+ *                                                                          *
+ * Permission to use, copy, modify, and/or distribute this software for any *
+ * purpose with or without fee is hereby granted.                           *
+ *                                                                          *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES *
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF         *
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR  *
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES   *
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN    *
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF  *
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.           *
+ ****************************************************************************/
+
+#include "regex.h"
+#include <stdlib.h>
+
+int bfs_regcomp(regex_t *preg, const char *regex, int cflags, enum bfs_regex_type type) {
+#if BFS_WITH_ONIGURUMA
+	// Oniguruma's POSIX wrapper uses the selected default syntax when REG_EXTENDED is set
+	cflags |= REG_EXTENDED;
+
+	switch (type) {
+	case BFS_REGEX_POSIX_BASIC:
+		onig_set_default_syntax(ONIG_SYNTAX_POSIX_BASIC);
+		break;
+	case BFS_REGEX_POSIX_EXTENDED:
+		onig_set_default_syntax(ONIG_SYNTAX_POSIX_EXTENDED);
+		break;
+	case BFS_REGEX_EMACS:
+		onig_set_default_syntax(ONIG_SYNTAX_EMACS);
+		break;
+	case BFS_REGEX_GREP:
+		onig_set_default_syntax(ONIG_SYNTAX_GREP);
+		break;
+	}
+#else
+	switch (type) {
+	case BFS_REGEX_POSIX_BASIC:
+		cflags &= ~REG_EXTENDED;
+		break;
+	case BFS_REGEX_POSIX_EXTENDED:
+		cflags |= REG_EXTENDED;
+		break;
+	default:
+		return REG_BADPAT;
+	}
+#endif
+
+	return regcomp(preg, regex, cflags);
+}
+
+char *bfs_regerror(int err, const regex_t *regex) {
+	size_t len = regerror(err, regex, NULL, 0);
+	char *str = malloc(len);
+	if (str) {
+		regerror(err, regex, str, len);
+	}
+	return str;
+}