1 files changed, 230 insertions, 0 deletions
diff --git a/contrib/bc/src/lex.c b/contrib/bc/src/lex.c
new file mode 100644
index 000000000000..a229f1964d5c
--- /dev/null
+++ b/contrib/bc/src/lex.c
@@ -0,0 +1,230 @@
+/*
+ * *****************************************************************************
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2018-2021 Gavin D. Howard and contributors.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ * *****************************************************************************
+ *
+ * Common code for the lexers.
+ *
+ */
+
+#include <assert.h>
+#include <ctype.h>
+#include <stdbool.h>
+#include <string.h>
+
+#include <lex.h>
+#include <vm.h>
+#include <bc.h>
+
+void bc_lex_invalidChar(BcLex *l, char c) {
+	l->t = BC_LEX_INVALID;
+	bc_lex_verr(l, BC_ERR_PARSE_CHAR, c);
+}
+
+void bc_lex_lineComment(BcLex *l) {
+	l->t = BC_LEX_WHITESPACE;
+	while (l->i < l->len && l->buf[l->i] != '\n') l->i += 1;
+}
+
+void bc_lex_comment(BcLex *l) {
+
+	size_t i, nlines = 0;
+	const char *buf = l->buf;
+	bool end = false;
+	char c;
+
+	l->i += 1;
+	l->t = BC_LEX_WHITESPACE;
+
+	for (i = l->i; !end; i += !end) {
+
+		for (; (c = buf[i]) && c != '*'; ++i) nlines += (c == '\n');
+
+		if (BC_ERR(!c || buf[i + 1] == '\0')) {
+			l->i = i;
+			bc_lex_err(l, BC_ERR_PARSE_COMMENT);
+		}
+
+		end = buf[i + 1] == '/';
+	}
+
+	l->i = i + 2;
+	l->line += nlines;
+}
+
+void bc_lex_whitespace(BcLex *l) {
+	char c;
+	l->t = BC_LEX_WHITESPACE;
+	for (c = l->buf[l->i]; c != '\n' && isspace(c); c = l->buf[++l->i]);
+}
+
+void bc_lex_commonTokens(BcLex *l, char c) {
+	if (!c) l->t = BC_LEX_EOF;
+	else if (c == '\n') l->t = BC_LEX_NLINE;
+	else bc_lex_whitespace(l);
+}
+
+static size_t bc_lex_num(BcLex *l, char start, bool int_only) {
+
+	const char *buf = l->buf + l->i;
+	size_t i;
+	char c;
+	bool last_pt, pt = (start == '.');
+
+	for (i = 0; (c = buf[i]) && (BC_LEX_NUM_CHAR(c, pt, int_only) ||
+	                             (c == '\\' && buf[i + 1] == '\n')); ++i)
+	{
+		if (c == '\\') {
+
+			if (buf[i + 1] == '\n') {
+
+				i += 2;
+
+				// Make sure to eat whitespace at the beginning of the line.
+				while(isspace(buf[i]) && buf[i] != '\n') i += 1;
+
+				c = buf[i];
+
+				if (!BC_LEX_NUM_CHAR(c, pt, int_only)) break;
+			}
+			else break;
+		}
+
+		last_pt = (c == '.');
+		if (pt && last_pt) break;
+		pt = pt || last_pt;
+
+		bc_vec_push(&l->str, &c);
+	}
+
+	return i;
+}
+
+void bc_lex_number(BcLex *l, char start) {
+
+	l->t = BC_LEX_NUMBER;
+
+	bc_vec_popAll(&l->str);
+	bc_vec_push(&l->str, &start);
+
+	l->i += bc_lex_num(l, start, false);
+
+#if BC_ENABLE_EXTRA_MATH
+	{
+		char c = l->buf[l->i];
+
+		if (c == 'e') {
+
+#if BC_ENABLED
+			if (BC_IS_POSIX) bc_lex_err(l, BC_ERR_POSIX_EXP_NUM);
+#endif // BC_ENABLED
+
+			bc_vec_push(&l->str, &c);
+			l->i += 1;
+			c = l->buf[l->i];
+
+			if (c == BC_LEX_NEG_CHAR) {
+				bc_vec_push(&l->str, &c);
+				l->i += 1;
+				c = l->buf[l->i];
+			}
+
+			if (BC_ERR(!BC_LEX_NUM_CHAR(c, false, true)))
+				bc_lex_verr(l, BC_ERR_PARSE_CHAR, c);
+
+			l->i += bc_lex_num(l, 0, true);
+		}
+	}
+#endif // BC_ENABLE_EXTRA_MATH
+
+	bc_vec_pushByte(&l->str, '\0');
+}
+
+void bc_lex_name(BcLex *l) {
+
+	size_t i = 0;
+	const char *buf = l->buf + l->i - 1;
+	char c = buf[i];
+
+	l->t = BC_LEX_NAME;
+
+	while ((c >= 'a' && c <= 'z') || isdigit(c) || c == '_') c = buf[++i];
+
+	bc_vec_string(&l->str, i, buf);
+
+	// Increment the index. We minus 1 because it has already been incremented.
+	l->i += i - 1;
+}
+
+void bc_lex_init(BcLex *l) {
+	BC_SIG_ASSERT_LOCKED;
+	assert(l != NULL);
+	bc_vec_init(&l->str, sizeof(char), NULL);
+}
+
+void bc_lex_free(BcLex *l) {
+	BC_SIG_ASSERT_LOCKED;
+	assert(l != NULL);
+	bc_vec_free(&l->str);
+}
+
+void bc_lex_file(BcLex *l, const char *file) {
+	assert(l != NULL && file != NULL);
+	l->line = 1;
+	vm.file = file;
+}
+
+void bc_lex_next(BcLex *l) {
+
+	assert(l != NULL);
+
+	l->last = l->t;
+	l->line += (l->i != 0 && l->buf[l->i - 1] == '\n');
+
+	if (BC_ERR(l->last == BC_LEX_EOF)) bc_lex_err(l, BC_ERR_PARSE_EOF);
+
+	l->t = BC_LEX_EOF;
+
+	if (l->i == l->len) return;
+
+	// Loop until failure or we don't have whitespace. This
+	// is so the parser doesn't get inundated with whitespace.
+	do {
+		vm.next(l);
+	} while (l->t == BC_LEX_WHITESPACE);
+}
+
+void bc_lex_text(BcLex *l, const char *text) {
+	assert(l != NULL && text != NULL);
+	l->buf = text;
+	l->i = 0;
+	l->len = strlen(text);
+	l->t = l->last = BC_LEX_INVALID;
+	bc_lex_next(l);
+}