1 files changed, 67 insertions, 0 deletions
diff --git a/bin/bitlex.l b/bin/bitlex.l
new file mode 100644
index 00000000..c6519b39
--- /dev/null
+++ b/bin/bitlex.l
@@ -0,0 +1,67 @@
+/* Copyright (C) 2019  June McEnroe <june@causal.agency>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+%option noinput
+%option nounput
+
+%{
+
+#include <stdint.h>
+
+static uint64_t parseInt(uint64_t base, const char *str) {
+	uint64_t num = 0;
+	for (const char *ch = str; *ch; ++ch) {
+		if (*ch == '_') continue;
+		num *= base;
+		if (*ch >= '0' && *ch <= '9') num += *ch - '0';
+		if (*ch >= 'A' && *ch <= 'F') num += 0xA + *ch - 'A';
+		if (*ch >= 'a' && *ch <= 'f') num += 0xA + *ch - 'a';
+	}
+	return num;
+}
+
+%}
+
+%%
+
+[ \t\n]	;
+
+0b[01_]+ {
+	yylval = parseInt(2, &yytext[2]);
+	return Int;
+}
+0[0-7_]+ {
+	yylval = parseInt(8, &yytext[1]);
+	return Int;
+}
+[0-9][0-9_]* {
+	yylval = parseInt(10, yytext);
+	return Int;
+}
+0x[0-9A-Fa-f_]+ {
+	yylval = parseInt(16, &yytext[2]);
+	return Int;
+}
+'.' {
+	yylval = yytext[1];
+	return Int;
+}
+
+"<<"	return Shl;
+">>"	return Shr;
+"->>"	return Sar;
+
+.	return yytext[0];