LibPDF: Move consume and match helper functions to the Reader class

Userland/Libraries/LibPDF/Reader.cpp

@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2021, Matthew Olsson <mattco@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibPDF/Reader.h>
+#include <ctype.h>
+
+namespace PDF {
+
+bool Reader::matches_eol() const
+{
+    return matches_any(0xa, 0xd);
+}
+
+bool Reader::matches_whitespace() const
+{
+    return matches_eol() || matches_any(0, 0x9, 0xc, ' ');
+}
+
+bool Reader::matches_number() const
+{
+    if (done())
+        return false;
+    auto ch = peek();
+    return isdigit(ch) || ch == '-' || ch == '+';
+}
+
+bool Reader::matches_delimiter() const
+{
+    return matches_any('(', ')', '<', '>', '[', ']', '{', '}', '/', '%');
+}
+
+bool Reader::matches_regular_character() const
+{
+    return !matches_delimiter() && !matches_whitespace();
+}
+
+bool Reader::consume_eol()
+{
+    if (done()) {
+        return false;
+    }
+    if (matches("\r\n")) {
+        consume(2);
+        return true;
+    }
+    auto consumed = consume();
+    return consumed == 0xd || consumed == 0xa;
+}
+
+bool Reader::consume_whitespace()
+{
+    bool consumed = false;
+    while (matches_whitespace()) {
+        consumed = true;
+        consume();
+    }
+    return consumed;
+}
+
+char Reader::consume()
+{
+    return read();
+}
+
+void Reader::consume(int amount)
+{
+    for (size_t i = 0; i < static_cast<size_t>(amount); i++)
+        consume();
+}
+
+bool Reader::consume(char ch)
+{
+    return consume() == ch;
+}
+
+}