diff options
| -rw-r--r-- | cores/arduino/Stream.cpp | 66 | ||||
| -rw-r--r-- | cores/arduino/Stream.h | 42 |
2 files changed, 62 insertions, 46 deletions
diff --git a/cores/arduino/Stream.cpp b/cores/arduino/Stream.cpp index b31942f..f665465 100644 --- a/cores/arduino/Stream.cpp +++ b/cores/arduino/Stream.cpp @@ -26,7 +26,6 @@ #include "Stream.h" #define PARSE_TIMEOUT 1000 // default number of milli-seconds to wait -#define NO_SKIP_CHAR 1 // a magic char not found in a valid ASCII numeric field // private method to read stream with timeout int Stream::timedRead() @@ -54,14 +53,30 @@ int Stream::timedPeek() // returns peek of the next digit in the stream or -1 if timeout // discards non-numeric characters -int Stream::peekNextDigit() +int Stream::peekNextDigit(LookaheadMode lookahead, bool detectDecimal) { int c; while (1) { c = timedPeek(); - if (c < 0) return c; // timeout - if (c == '-') return c; - if (c >= '0' && c <= '9') return c; + + if( c < 0 || + c == '-' || + (c >= '0' && c <= '9') || + (detectDecimal && c == '.')) return c; + + switch( lookahead ){ + case SKIP_NONE: return -1; // Fail code. + case SKIP_WHITESPACE: + switch( c ){ + case ' ': + case '\t': + case '\r': + case '\n': break; + default: return -1; // Fail code. + } + case SKIP_ALL: + break; + } read(); // discard non-numeric } } @@ -107,31 +122,25 @@ bool Stream::findUntil(char *target, size_t targetLen, char *terminator, size_t } } - // returns the first valid (long) integer value from the current position. -// initial characters that are not digits (or the minus sign) are skipped -// function is terminated by the first character that is not a digit. -long Stream::parseInt() -{ - return parseInt(NO_SKIP_CHAR); // terminate on first non-digit character (or timeout) -} - -// as above but a given skipChar is ignored -// this allows format characters (typically commas) in values to be ignored -long Stream::parseInt(char skipChar) +// lookahead determines how parseInt looks ahead in the stream. +// See LookaheadMode enumeration at the top of the file. +// Lookahead is terminated by the first character that is not a valid part of an integer. +// Once parsing commences, 'ignore' will be skipped in the stream. +long Stream::parseInt(LookaheadMode lookahead, char ignore) { bool isNegative = false; long value = 0; int c; - c = peekNextDigit(); + c = peekNextDigit(lookahead, false); // ignore non numeric leading characters if(c < 0) return 0; // zero returned if timeout do{ - if(c == skipChar) - ; // ignore this charactor + if(c == ignore) + ; // ignore this character else if(c == '-') isNegative = true; else if(c >= '0' && c <= '9') // is c a digit? @@ -139,36 +148,29 @@ long Stream::parseInt(char skipChar) read(); // consume the character we got with peek c = timedPeek(); } - while( (c >= '0' && c <= '9') || c == skipChar ); + while( (c >= '0' && c <= '9') || c == ignore ); if(isNegative) value = -value; return value; } - // as parseInt but returns a floating point value -float Stream::parseFloat() +float Stream::parseFloat(LookaheadMode lookahead, char ignore) { - return parseFloat(NO_SKIP_CHAR); -} - -// as above but the given skipChar is ignored -// this allows format characters (typically commas) in values to be ignored -float Stream::parseFloat(char skipChar){ bool isNegative = false; bool isFraction = false; long value = 0; - char c; + int c; float fraction = 1.0; - c = peekNextDigit(); + c = peekNextDigit(lookahead, true); // ignore non numeric leading characters if(c < 0) return 0; // zero returned if timeout do{ - if(c == skipChar) + if(c == ignore) ; // ignore else if(c == '-') isNegative = true; @@ -182,7 +184,7 @@ float Stream::parseFloat(char skipChar){ read(); // consume the character we got with peek c = timedPeek(); } - while( (c >= '0' && c <= '9') || c == '.' || c == skipChar ); + while( (c >= '0' && c <= '9') || (c == '.' && !isFraction) || c == ignore ); if(isNegative) value = -value; diff --git a/cores/arduino/Stream.h b/cores/arduino/Stream.h index 15f6761..db71bb6 100644 --- a/cores/arduino/Stream.h +++ b/cores/arduino/Stream.h @@ -28,13 +28,24 @@ // compatability macros for testing /* #define getInt() parseInt() -#define getInt(skipChar) parseInt(skipchar) +#define getInt(ignore) parseInt(ignore) #define getFloat() parseFloat() -#define getFloat(skipChar) parseFloat(skipChar) +#define getFloat(ignore) parseFloat(ignore) #define getString( pre_string, post_string, buffer, length) readBytesBetween( pre_string, terminator, buffer, length) */ +// This enumeration provides the lookahead options for parseInt(), parseFloat() +// The rules set out here are used until either the first valid character is found +// or a time out occurs due to lack of input. +enum LookaheadMode{ + SKIP_ALL, // All invalid characters are ignored. + SKIP_NONE, // Nothing is skipped, and the stream is not touched unless the first waiting character is valid. + SKIP_WHITESPACE // Only tabs, spaces, line feeds & carriage returns are skipped. +}; + +#define NO_IGNORE_CHAR '\x01' // a char not found in a valid ASCII numeric field + class Stream : public Print { protected: @@ -42,7 +53,7 @@ class Stream : public Print unsigned long _startMillis; // used for timeout measurement int timedRead(); // private method to read stream with timeout int timedPeek(); // private method to peek stream with timeout - int peekNextDigit(); // returns the next numeric digit in the stream or -1 if timeout + int peekNextDigit(LookaheadMode lookahead, bool detectDecimal); // returns the next numeric digit in the stream or -1 if timeout public: virtual int available() = 0; @@ -72,12 +83,15 @@ class Stream : public Print bool findUntil(char *target, size_t targetLen, char *terminate, size_t termLen); // as above but search ends if the terminate string is found bool findUntil(uint8_t *target, size_t targetLen, char *terminate, size_t termLen) {return findUntil((char *)target, targetLen, terminate, termLen); } + long parseInt(LookaheadMode lookahead = SKIP_ALL, char ignore = NO_IGNORE_CHAR); + // returns the first valid (long) integer value from the current position. + // lookahead determines how parseInt looks ahead in the stream. + // See LookaheadMode enumeration at the top of the file. + // Lookahead is terminated by the first character that is not a valid part of an integer. + // Once parsing commences, 'ignore' will be skipped in the stream. - long parseInt(); // returns the first valid (long) integer value from the current position. - // initial characters that are not digits (or the minus sign) are skipped - // integer is terminated by the first character that is not a digit. - - float parseFloat(); // float version of parseInt + float parseFloat(LookaheadMode lookahead = SKIP_ALL, char ignore = NO_IGNORE_CHAR); + // float version of parseInt size_t readBytes( char *buffer, size_t length); // read chars from stream into buffer size_t readBytes( uint8_t *buffer, size_t length) { return readBytes((char *)buffer, length); } @@ -94,11 +108,11 @@ class Stream : public Print String readStringUntil(char terminator); protected: - long parseInt(char skipChar); // as above but the given skipChar is ignored - // as above but the given skipChar is ignored - // this allows format characters (typically commas) in values to be ignored - - float parseFloat(char skipChar); // as above but the given skipChar is ignored + long parseInt(char ignore) { return parseInt(SKIP_ALL, ignore); } + float parseFloat(char ignore) { return parseFloat(SKIP_ALL, ignore); } + // These overload exists for compatibility with any class that has derived + // Stream and used parseFloat/Int with a custom ignore character. To keep + // the public API simple, these overload remains protected. struct MultiTarget { const char *str; // string you're searching for @@ -111,5 +125,5 @@ class Stream : public Print int findMulti(struct MultiTarget *targets, int tCount); }; - +#undef NO_IGNORE_CHAR #endif |