Diff: Parser.cpp

Revision:

0:099f76422485

Child:

4:059b8b90e0d9

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Parser.cpp	Thu Jul 03 20:38:04 2014 +0200
@@ -0,0 +1,180 @@
+/*
+ * Parser.cpp
+ *
+ * Created on: Nov 1, 2013
+ * * Authors: Vincent Wochnik <v.wochnik@gmail.com>
+ *
+ * Copyright (c) 2013 Cumulocity GmbH
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include "Parser.h"
+
+#define STATE_BLANK 0
+#define STATE_STRUCTURE 1
+#define STATE_VALUE 2
+#define STATE_INQUOTES 3
+#define STATE_AFTERQUOTE 4
+#define STATE_COMPLETE 5
+#define STATE_ERROR 6
+
+Parser::Parser()
+{
+    reset();
+}
+
+uint8_t Parser::readFrom(AbstractDataSource& source, ParsedRecord& record)
+{
+    uint8_t status; char read;
+
+    reset();
+    record.set(NULL, 0);
+
+    while ((_state < STATE_COMPLETE) &&
+           (((read = source.read()) > 0 ) ||
+            ((status = source.status()) == DS_STATUS_OK)))
+        parse(read);
+
+    if (_state == STATE_COMPLETE)
+        record.set(_buffer, _count);
+
+    if (_state == STATE_COMPLETE)
+        return PARSER_SUCCESS;
+    else if (_state == STATE_BLANK)
+        if (status == DS_STATUS_CLOSED)
+            return PARSER_END_OF_RESPONSE;
+        else
+            return PARSER_TIMEOUT_ERROR;
+    else
+        if (status == DS_STATUS_TIMEOUT)
+            return PARSER_TIMEOUT_ERROR;
+        else
+            return PARSER_PARSE_ERROR;
+}
+
+void Parser::parse(char c)
+{
+    if (_ptr-_buffer >= SMARTREST_PARSER_BUFFER_SIZE) {
+        _state = STATE_ERROR;
+        return;
+    }
+
+    switch (_state) {
+    case STATE_BLANK:
+        _state = STATE_STRUCTURE;
+    case STATE_STRUCTURE:
+        switch (c) {
+        case ' ':
+        case '\t':
+        case '\r':
+            break;
+        case '"':
+            _state = STATE_INQUOTES;
+            break;
+        case ',':
+            close();
+            break;
+        case '\0':
+        case '\n':
+            if ((_count == 0) && (_length == 0)) {
+                _state = STATE_BLANK;
+            } else {
+                close();
+                _state = STATE_COMPLETE;
+            }
+            break;
+        default:
+            if (_length > 0) {
+                _state = STATE_ERROR;
+            } else {
+                _state = STATE_VALUE;
+                parse(c);
+            }
+            break;
+        }
+        break;
+    case STATE_VALUE:
+        switch (c) {
+        case ',':
+        case '\n':
+            _state = STATE_STRUCTURE;
+            parse(c);
+            break;
+        case '"':
+            _state = STATE_ERROR;
+            break;
+        default:
+            if ((c == ' ') || (c == '\t') || (c == '\r'))
+                _trailing++;
+            else
+                _trailing = 0;
+            append(c);
+            break;
+        }
+        break;
+    case STATE_INQUOTES:
+        switch (c) {
+        case '"':
+            _state = STATE_AFTERQUOTE;
+            break;
+        default:
+            append(c);
+            break;
+        }
+        break;
+    case STATE_AFTERQUOTE:
+        switch (c) {
+        case '"':
+            append(c);
+            _state = STATE_INQUOTES;
+            break;
+        default:
+            _state = STATE_STRUCTURE;
+            parse(c);
+            break;
+        }
+        break;
+    }
+}
+
+void Parser::append(char c)
+{
+    *_ptr++ = c;
+    _length++;
+}
+
+void Parser::close()
+{
+    _ptr -= _trailing;
+    *_ptr++ = 0;
+    _trailing = 0;
+    _length = 0;
+    _count++;
+}
+
+void Parser::reset()
+{
+    _state = STATE_BLANK;
+    _ptr = _buffer;
+    _count = 0;
+    _trailing = 0;
+    _length = 0;
+}