First class data visualization and communication library with embedded devices. Code is maintained at github.com/Overdrivr/Telemetry
Dependents: telemetry_car_demo telemetry_demo_FRDM-TFC telemetry_example_01 telemetry_indexed_data_demo ... more
c_api/framing.cpp@6:f5e1b079bffd, 2016-03-09 (annotated)
- Committer:
- Overdrivr
- Date:
- Wed Mar 09 13:41:27 2016 +0000
- Revision:
- 6:f5e1b079bffd
- Parent:
- c_api/framing.c@5:cd94bb58e096
Fixed build.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
Overdrivr | 3:37d2d127bc83 | 1 | #include "framing.h" |
Overdrivr | 3:37d2d127bc83 | 2 | |
Overdrivr | 3:37d2d127bc83 | 3 | typedef enum _state |
Overdrivr | 3:37d2d127bc83 | 4 | { |
Overdrivr | 3:37d2d127bc83 | 5 | IDLE, // No incoming frame is in process |
Overdrivr | 3:37d2d127bc83 | 6 | ESCAPING, // incoming frame in process, next character to be escaped |
Overdrivr | 3:37d2d127bc83 | 7 | ACTIVE // frame in process |
Overdrivr | 3:37d2d127bc83 | 8 | } _state ; |
Overdrivr | 3:37d2d127bc83 | 9 | |
Overdrivr | 3:37d2d127bc83 | 10 | typedef struct storage storage; |
Overdrivr | 3:37d2d127bc83 | 11 | struct storage |
Overdrivr | 3:37d2d127bc83 | 12 | { |
Overdrivr | 3:37d2d127bc83 | 13 | uint8_t * ptr; |
Overdrivr | 3:37d2d127bc83 | 14 | uint32_t size; |
Overdrivr | 3:37d2d127bc83 | 15 | uint32_t cursor; |
Overdrivr | 3:37d2d127bc83 | 16 | |
Overdrivr | 3:37d2d127bc83 | 17 | }; |
Overdrivr | 3:37d2d127bc83 | 18 | |
Overdrivr | 3:37d2d127bc83 | 19 | static storage incomingStorage; |
Overdrivr | 3:37d2d127bc83 | 20 | static storage outgoingStorage; |
Overdrivr | 3:37d2d127bc83 | 21 | |
Overdrivr | 3:37d2d127bc83 | 22 | int8_t safe_append(storage * s, uint8_t byte); |
Overdrivr | 3:37d2d127bc83 | 23 | |
Overdrivr | 3:37d2d127bc83 | 24 | static uint8_t SOF_; |
Overdrivr | 3:37d2d127bc83 | 25 | static uint8_t EOF_; |
Overdrivr | 3:37d2d127bc83 | 26 | static uint8_t ESC_; |
Overdrivr | 3:37d2d127bc83 | 27 | |
Overdrivr | 3:37d2d127bc83 | 28 | static _state incoming_state; |
Overdrivr | 3:37d2d127bc83 | 29 | |
Overdrivr | 3:37d2d127bc83 | 30 | void (*on_incoming_frame_cb)(uint8_t * storage, uint32_t occupiedSize); |
Overdrivr | 3:37d2d127bc83 | 31 | void (*on_error_cb)(int32_t errCode); |
Overdrivr | 3:37d2d127bc83 | 32 | |
Overdrivr | 3:37d2d127bc83 | 33 | void initialize_framing() |
Overdrivr | 3:37d2d127bc83 | 34 | { |
Overdrivr | 3:37d2d127bc83 | 35 | incomingStorage.ptr = NULL; |
Overdrivr | 3:37d2d127bc83 | 36 | outgoingStorage.ptr = NULL; |
Overdrivr | 3:37d2d127bc83 | 37 | |
Overdrivr | 3:37d2d127bc83 | 38 | incomingStorage.size = 0; |
Overdrivr | 3:37d2d127bc83 | 39 | outgoingStorage.size = 0; |
Overdrivr | 3:37d2d127bc83 | 40 | |
Overdrivr | 3:37d2d127bc83 | 41 | incomingStorage.cursor = 0; |
Overdrivr | 3:37d2d127bc83 | 42 | incomingStorage.cursor = 0; |
Overdrivr | 3:37d2d127bc83 | 43 | |
Overdrivr | 3:37d2d127bc83 | 44 | SOF_ = 0xF7; |
Overdrivr | 3:37d2d127bc83 | 45 | EOF_ = 0x7F; |
Overdrivr | 3:37d2d127bc83 | 46 | ESC_ = 0x7D; |
Overdrivr | 3:37d2d127bc83 | 47 | |
Overdrivr | 3:37d2d127bc83 | 48 | incoming_state = IDLE; |
Overdrivr | 3:37d2d127bc83 | 49 | } |
Overdrivr | 3:37d2d127bc83 | 50 | |
Overdrivr | 3:37d2d127bc83 | 51 | void outgoing_storage(uint8_t * buf, uint32_t bufSize) |
Overdrivr | 3:37d2d127bc83 | 52 | { |
Overdrivr | 3:37d2d127bc83 | 53 | outgoingStorage.ptr = buf; |
Overdrivr | 3:37d2d127bc83 | 54 | outgoingStorage.size = bufSize; |
Overdrivr | 3:37d2d127bc83 | 55 | } |
Overdrivr | 3:37d2d127bc83 | 56 | |
Overdrivr | 3:37d2d127bc83 | 57 | void begin() |
Overdrivr | 3:37d2d127bc83 | 58 | { |
Overdrivr | 3:37d2d127bc83 | 59 | if(outgoingStorage.size == 0 || outgoingStorage.ptr == NULL) |
Overdrivr | 3:37d2d127bc83 | 60 | return; |
Overdrivr | 3:37d2d127bc83 | 61 | |
Overdrivr | 3:37d2d127bc83 | 62 | outgoingStorage.cursor = 0; |
Overdrivr | 3:37d2d127bc83 | 63 | |
Overdrivr | 3:37d2d127bc83 | 64 | // Should not fail |
Overdrivr | 3:37d2d127bc83 | 65 | safe_append(&outgoingStorage,SOF_); |
Overdrivr | 3:37d2d127bc83 | 66 | } |
Overdrivr | 3:37d2d127bc83 | 67 | |
Overdrivr | 3:37d2d127bc83 | 68 | void append(uint8_t byte) |
Overdrivr | 3:37d2d127bc83 | 69 | { |
Overdrivr | 3:37d2d127bc83 | 70 | if(outgoingStorage.size == 0 || outgoingStorage.ptr == NULL) |
Overdrivr | 3:37d2d127bc83 | 71 | return; |
Overdrivr | 3:37d2d127bc83 | 72 | |
Overdrivr | 3:37d2d127bc83 | 73 | // byte == to flag, need to escape it |
Overdrivr | 3:37d2d127bc83 | 74 | if(byte == SOF_ || byte == EOF_ || byte == ESC_) |
Overdrivr | 3:37d2d127bc83 | 75 | { |
Overdrivr | 3:37d2d127bc83 | 76 | if(!safe_append(&outgoingStorage,ESC_)) |
Overdrivr | 3:37d2d127bc83 | 77 | return; |
Overdrivr | 3:37d2d127bc83 | 78 | } |
Overdrivr | 3:37d2d127bc83 | 79 | |
Overdrivr | 3:37d2d127bc83 | 80 | if(!safe_append(&outgoingStorage,byte)) |
Overdrivr | 3:37d2d127bc83 | 81 | return; |
Overdrivr | 3:37d2d127bc83 | 82 | } |
Overdrivr | 3:37d2d127bc83 | 83 | |
Overdrivr | 3:37d2d127bc83 | 84 | void append2(uint16_t twobytes) |
Overdrivr | 3:37d2d127bc83 | 85 | { |
Overdrivr | 3:37d2d127bc83 | 86 | uint8_t * ptr = (uint8_t*)(&twobytes); |
Overdrivr | 3:37d2d127bc83 | 87 | append(ptr[0]); |
Overdrivr | 3:37d2d127bc83 | 88 | append(ptr[1]); |
Overdrivr | 3:37d2d127bc83 | 89 | } |
Overdrivr | 3:37d2d127bc83 | 90 | |
Overdrivr | 3:37d2d127bc83 | 91 | void append4(uint32_t fourbytes) |
Overdrivr | 3:37d2d127bc83 | 92 | { |
Overdrivr | 3:37d2d127bc83 | 93 | uint8_t * ptr = (uint8_t*)(&fourbytes); |
Overdrivr | 3:37d2d127bc83 | 94 | append(ptr[0]); |
Overdrivr | 3:37d2d127bc83 | 95 | append(ptr[1]); |
Overdrivr | 3:37d2d127bc83 | 96 | append(ptr[2]); |
Overdrivr | 3:37d2d127bc83 | 97 | append(ptr[3]); |
Overdrivr | 3:37d2d127bc83 | 98 | } |
Overdrivr | 3:37d2d127bc83 | 99 | |
Overdrivr | 3:37d2d127bc83 | 100 | uint32_t end() |
Overdrivr | 3:37d2d127bc83 | 101 | { |
Overdrivr | 3:37d2d127bc83 | 102 | if(outgoingStorage.size == 0 || outgoingStorage.ptr == NULL) |
Overdrivr | 3:37d2d127bc83 | 103 | return 0; |
Overdrivr | 3:37d2d127bc83 | 104 | |
Overdrivr | 3:37d2d127bc83 | 105 | if(!safe_append(&outgoingStorage,EOF_)) |
Overdrivr | 3:37d2d127bc83 | 106 | return 0; |
Overdrivr | 3:37d2d127bc83 | 107 | |
Overdrivr | 3:37d2d127bc83 | 108 | return outgoingStorage.cursor; |
Overdrivr | 3:37d2d127bc83 | 109 | } |
Overdrivr | 3:37d2d127bc83 | 110 | |
Overdrivr | 3:37d2d127bc83 | 111 | void incoming_storage(uint8_t * buf, uint32_t bufSize) |
Overdrivr | 3:37d2d127bc83 | 112 | { |
Overdrivr | 3:37d2d127bc83 | 113 | incomingStorage.ptr = buf; |
Overdrivr | 3:37d2d127bc83 | 114 | incomingStorage.size = bufSize; |
Overdrivr | 3:37d2d127bc83 | 115 | } |
Overdrivr | 3:37d2d127bc83 | 116 | |
Overdrivr | 3:37d2d127bc83 | 117 | void set_on_incoming_frame(void (*callback)(uint8_t * storage, uint32_t occupiedSize)) |
Overdrivr | 3:37d2d127bc83 | 118 | { |
Overdrivr | 3:37d2d127bc83 | 119 | on_incoming_frame_cb = callback; |
Overdrivr | 3:37d2d127bc83 | 120 | } |
Overdrivr | 3:37d2d127bc83 | 121 | |
Overdrivr | 3:37d2d127bc83 | 122 | void set_on_incoming_error(void (*callback)(int32_t errCode)) |
Overdrivr | 3:37d2d127bc83 | 123 | { |
Overdrivr | 3:37d2d127bc83 | 124 | on_error_cb = callback; |
Overdrivr | 3:37d2d127bc83 | 125 | } |
Overdrivr | 3:37d2d127bc83 | 126 | |
Overdrivr | 3:37d2d127bc83 | 127 | void feed(uint8_t byte) |
Overdrivr | 3:37d2d127bc83 | 128 | { |
Overdrivr | 3:37d2d127bc83 | 129 | if(incomingStorage.size == 0 || incomingStorage.ptr == NULL) |
Overdrivr | 3:37d2d127bc83 | 130 | return; |
Overdrivr | 3:37d2d127bc83 | 131 | |
Overdrivr | 3:37d2d127bc83 | 132 | if(incoming_state == ESCAPING) |
Overdrivr | 3:37d2d127bc83 | 133 | { |
Overdrivr | 3:37d2d127bc83 | 134 | if(!safe_append(&incomingStorage,byte)) |
Overdrivr | 3:37d2d127bc83 | 135 | { |
Overdrivr | 3:37d2d127bc83 | 136 | incoming_state = IDLE; |
Overdrivr | 3:37d2d127bc83 | 137 | return; |
Overdrivr | 3:37d2d127bc83 | 138 | } |
Overdrivr | 3:37d2d127bc83 | 139 | incoming_state = ACTIVE; |
Overdrivr | 3:37d2d127bc83 | 140 | return; |
Overdrivr | 3:37d2d127bc83 | 141 | } |
Overdrivr | 3:37d2d127bc83 | 142 | |
Overdrivr | 3:37d2d127bc83 | 143 | if(byte == SOF_) |
Overdrivr | 3:37d2d127bc83 | 144 | { |
Overdrivr | 3:37d2d127bc83 | 145 | incoming_state = ACTIVE; |
Overdrivr | 3:37d2d127bc83 | 146 | incomingStorage.cursor = 0; |
Overdrivr | 3:37d2d127bc83 | 147 | return; |
Overdrivr | 3:37d2d127bc83 | 148 | } |
Overdrivr | 3:37d2d127bc83 | 149 | |
Overdrivr | 3:37d2d127bc83 | 150 | if(incoming_state == ACTIVE) |
Overdrivr | 3:37d2d127bc83 | 151 | { |
Overdrivr | 3:37d2d127bc83 | 152 | if(byte == EOF_) |
Overdrivr | 3:37d2d127bc83 | 153 | { |
Overdrivr | 3:37d2d127bc83 | 154 | incoming_state = IDLE; |
Overdrivr | 3:37d2d127bc83 | 155 | on_incoming_frame_cb(incomingStorage.ptr, incomingStorage.cursor); |
Overdrivr | 3:37d2d127bc83 | 156 | } |
Overdrivr | 3:37d2d127bc83 | 157 | // Escape next character |
Overdrivr | 3:37d2d127bc83 | 158 | else if(byte == ESC_) |
Overdrivr | 3:37d2d127bc83 | 159 | { |
Overdrivr | 3:37d2d127bc83 | 160 | incoming_state = ESCAPING; |
Overdrivr | 3:37d2d127bc83 | 161 | } |
Overdrivr | 3:37d2d127bc83 | 162 | else |
Overdrivr | 3:37d2d127bc83 | 163 | { |
Overdrivr | 3:37d2d127bc83 | 164 | if(!safe_append(&incomingStorage,byte)) |
Overdrivr | 3:37d2d127bc83 | 165 | { |
Overdrivr | 3:37d2d127bc83 | 166 | incoming_state = IDLE; |
Overdrivr | 3:37d2d127bc83 | 167 | return; |
Overdrivr | 3:37d2d127bc83 | 168 | } |
Overdrivr | 3:37d2d127bc83 | 169 | incoming_state = ACTIVE; |
Overdrivr | 3:37d2d127bc83 | 170 | } |
Overdrivr | 3:37d2d127bc83 | 171 | } |
Overdrivr | 3:37d2d127bc83 | 172 | } |
Overdrivr | 3:37d2d127bc83 | 173 | |
Overdrivr | 3:37d2d127bc83 | 174 | int8_t safe_append(storage * s, uint8_t byte) |
Overdrivr | 3:37d2d127bc83 | 175 | { |
Overdrivr | 3:37d2d127bc83 | 176 | // Not enough space for 1 more character |
Overdrivr | 3:37d2d127bc83 | 177 | if(s->cursor + 1 >= s->size) |
Overdrivr | 3:37d2d127bc83 | 178 | return 0; |
Overdrivr | 3:37d2d127bc83 | 179 | |
Overdrivr | 3:37d2d127bc83 | 180 | s->ptr[s->cursor++] = byte; |
Overdrivr | 3:37d2d127bc83 | 181 | |
Overdrivr | 3:37d2d127bc83 | 182 | return 1; |
Overdrivr | 3:37d2d127bc83 | 183 | } |