const size_t maxCommandNumber = 50;
const size_t maxCommandSize = 3 * maxCommandNumber; // if commands fit on 2 characters and a comma, this is enough for maxCommandNumber commands
char receivedChars[maxCommandSize + 1]; // +1 for trailing null char required by cStrings
const char endMarker = '\n';
void func_L(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_Lp(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_L2(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_R(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_Rp(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_R2(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_D(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_Dp(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_D2(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_B(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_Bp(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_B2(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_U(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_Up(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_U2(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_F(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_Fp(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_F2(const char* s) {Serial.print(F("in Function ")); Serial.println(s);}
void func_unknown(const char* s) {Serial.print(F("Unknown commmand: ")); Serial.println(s);}
struct {
const char* label;
void (*func)(const char*);
} keys[] = {
{"L", func_L},
{"L'", func_Lp},
{"L2", func_L2},
{"R", func_R},
{"R'", func_Rp},
{"R2", func_R2},
{"D", func_D},
{"D'", func_Dp},
{"D2", func_D2},
{"B", func_B},
{"B'", func_Bp},
{"B2", func_B2},
{"U", func_U},
{"U'", func_Up},
{"U2", func_U2},
{"F", func_F},
{"F'", func_Fp},
{"F2", func_F2},
};
const size_t nbKeys = sizeof keys / sizeof keys[0];
bool findAndExecute(const char* s)
{
bool success = false;
for (size_t i = 0; i < nbKeys; i++)
if (!strcmp(s, keys[i].label)) {
keys[i].func(s);
success = true;
break;
}
if (!success) func_unknown(s);
return success;
}
bool commandAvailable()
{
static size_t commandIndex = 0;
static bool awaitEndMarkerError = false;
int incomingByte = Serial.read();
bool commandComplete = false;
if (incomingByte != -1) { // read returns -1 if there is nothing to read (faster than using available)
if (awaitEndMarkerError) {
if (incomingByte == endMarker) {
awaitEndMarkerError = false;
commandIndex = 0;
receivedChars[0] = '\0'; // discard what was there
commandComplete = true; // if we want to still notify the parser we got a command (here will be empty)
}
} else {
char incomingCharacter = incomingByte; // grab LSB as a char
if (incomingByte != endMarker) {
if (commandIndex < maxCommandSize) {
if (!isspace(incomingCharacter)) { // discard all spaces. could also add a test to only keep A-Z and ' and 2, whatever is legit in the command language
receivedChars[commandIndex++] = incomingCharacter;
receivedChars[commandIndex] = '\0'; // always maintain a correct cString
}
} else {
Serial.println(F("ERROR: Command line too big. Discarded.\n\t-> increase maxCommandNumber or send shorter command lines."));
awaitEndMarkerError = true;
}
} else {
commandIndex = 0;
commandComplete = true;
}
}
}
return commandComplete;
}
bool handleCommand()
{
bool success = true;
const char* separators = ",";
Serial.print(F("\nparsing : ")); Serial.println(receivedChars);
char* ptr = strtok(receivedChars, separators);
if (*ptr == '\0') Serial.println(F("Error: empty command"));
else
while (ptr) {
success &= findAndExecute(ptr);
ptr = strtok(NULL, separators);
}
return success;
}
void setup() {
Serial.begin(115200);
}
void loop() {
if (commandAvailable())
if (! handleCommand())
Serial.println(F("Some commands were not recognized"));
}
