init: Add C++ tokenizer.
Adds a C++ tokenizer along with unit tests.
This tokenizer will replace the current C implementation
which does a poor job of keeping track of pointers.
This CL is a prerequisite for up coming changes to
the parser. This CL does not wire up this tokenizer and
changes no exsiting code. All that builds is the unit tests.
Change-Id: Iec3740bce7153640adc5e5bbdc57e644cedf0038
TEST: Unit tests all pass. No leaks under valgrind
BUG: 22843198
diff --git a/init/parser/tokenizer.cpp b/init/parser/tokenizer.cpp
new file mode 100644
index 0000000..340e0d9
--- /dev/null
+++ b/init/parser/tokenizer.cpp
@@ -0,0 +1,129 @@
+// Copyright (C) 2015 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "tokenizer.h"
+
+namespace init {
+
+Tokenizer::Tokenizer(const std::string& data)
+ : data_(data), eof_(false), pos_(0), tok_start_(0) {
+ current_.type = TOK_START;
+
+ if (data.size() > 0) {
+ cur_char_ = data[0];
+ } else {
+ eof_ = true;
+ cur_char_ = '\0';
+ }
+}
+
+Tokenizer::~Tokenizer() {}
+
+const Tokenizer::Token& Tokenizer::current() {
+ return current_;
+}
+
+bool Tokenizer::Next() {
+ while (!eof_) {
+ AdvWhiteSpace();
+
+ // Check for comments.
+ if (cur_char_ == '#') {
+ AdvChar();
+ // Skip rest of line
+ while (!eof_ && cur_char_ != '\n') {
+ AdvChar();
+ }
+ }
+
+ if (eof_) {
+ break;
+ }
+
+ if (cur_char_ == '\0') {
+ AdvChar();
+ } else if (cur_char_ == '\n') {
+ current_.type = TOK_NEWLINE;
+ current_.text.clear();
+ AdvChar();
+ return true;
+ } else if (cur_char_ == '\\') {
+ AdvChar(); // skip backslash
+ // This is line continuation so
+ // do not generated TOK_NEWLINE at
+ // the next \n.
+ AdvUntil('\n');
+ AdvChar(); // skip \n
+ } else if (cur_char_ == '\"') {
+ AdvChar();
+ StartText();
+ // Grab everything until the next quote.
+ AdvUntil('\"');
+ EndText();
+ AdvChar(); // skip quote.
+ return true;
+ } else {
+ StartText();
+ AdvText();
+ EndText();
+ return true;
+ }
+ }
+ current_.type = TOK_END;
+ current_.text.clear();
+ return false;
+}
+
+void Tokenizer::AdvChar() {
+ pos_++;
+ if (pos_ < data_.size()) {
+ cur_char_ = data_[pos_];
+ } else {
+ eof_ = true;
+ cur_char_ = '\0';
+ }
+}
+
+void Tokenizer::AdvWhiteSpace() {
+ while (cur_char_ == '\t' || cur_char_ == '\r' || cur_char_ == ' ') {
+ AdvChar();
+ }
+}
+
+void Tokenizer::AdvUntil(char x) {
+ while (!eof_ && cur_char_ != x) {
+ AdvChar();
+ }
+}
+
+void Tokenizer::AdvText() {
+ while (cur_char_ != '\t' && cur_char_ != '\r' && cur_char_ != '\0' &&
+ cur_char_ != ' ' && cur_char_ != '\n' && cur_char_ != '#') {
+ AdvChar();
+ }
+}
+
+void Tokenizer::StartText() {
+ current_.text.clear();
+ tok_start_ = pos_;
+ current_.type = TOK_TEXT;
+}
+
+void Tokenizer::EndText() {
+ if (pos_ != tok_start_) {
+ current_.text.append(data_, tok_start_, pos_ - tok_start_);
+ }
+}
+
+} // namespace init
\ No newline at end of file