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dle encoder doc finished and hopefully correct

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This commit is contained in:
Robin Müller
2020-07-08 12:41:15 +02:00
parent 264914e86a
commit 94f9b1e1ef
2 changed files with 89 additions and 60 deletions
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21
globalfunctions/DleEncoder.h
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@ -14,9 +14,15 @@
* This encoder can be used to achieve a basic transport layer when using
* char based transmission systems.
* The passed source strean is converted into a encoded stream by adding
* a STX marker at the startr of the stream and an ETX marker at the end of
* the stream. Any STX, ETX and DLE occurences in the source stream are escaped
* by a DLE character.
* a STX marker at the start of the stream and an ETX marker at the end of
* the stream. Any STX, ETX, DLE and CR occurences in the source stream are
* escaped by a DLE character. The encoder also replaces escaped control chars
* by another char, so STX, ETX and CR should not appear anywhere in the actual
* encoded data stream.
*
* When using a strictly char based reception of packets enoded with DLE,
* STX can be used to notify a reader that actual data will start to arrive
* while ETX can be used to notify the reader that the data has ended.
*/
class DleEncoder: public HasReturnvaluesIF {
private:
@ -29,12 +35,13 @@ public:
static constexpr ReturnValue_t DECODING_ERROR = MAKE_RETURN_CODE(0x02);
//! Start Of Text character. First character is encoded stream
static const uint8_t STX = 0x02;
static constexpr uint8_t STX = 0x02;
//! End Of Text character. Last character in encoded stream
static const uint8_t ETX = 0x03;
static constexpr uint8_t ETX = 0x03;
//! Data Link Escape character. Used to escape STX, ETX and DLE occurences
//! in the source stream.
static const uint8_t DLE = 0x10;
static constexpr uint8_t DLE = 0x10;
static constexpr uint8_t CARRIAGE_RETURN = 0x0D;
/**
* Encodes the give data stream by preceding it with the STX marker
@ -54,7 +61,7 @@ public:
bool addStxEtx = true);
/**
* Converts an encoded stream back
* Converts an encoded stream back.
* @param sourceStream
* @param sourceStreamLen
* @param readLen