Pico-Arduino
Stream.h
1 /*
2  Stream.h - base class for character-based streams.
3  Copyright (c) 2010 David A. Mellis. All right reserved.
4 
5  This library is free software; you can redistribute it and/or
6  modify it under the terms of the GNU Lesser General Public
7  License as published by the Free Software Foundation; either
8  version 2.1 of the License, or (at your option) any later version.
9 
10  This library is distributed in the hope that it will be useful,
11  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  Lesser General Public License for more details.
14 
15  You should have received a copy of the GNU Lesser General Public
16  License along with this library; if not, write to the Free Software
17  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 
19  parsing functions based on TextFinder library by Michael Margolis
20 */
21 
22 #pragma once
23 
24 #include <inttypes.h>
25 #include "Print.h"
26 
27 // compatability macros for testing
28 /*
29 #define getInt() parseInt()
30 #define getInt(ignore) parseInt(ignore)
31 #define getFloat() parseFloat()
32 #define getFloat(ignore) parseFloat(ignore)
33 #define getString( pre_string, post_string, buffer, length)
34 readBytesBetween( pre_string, terminator, buffer, length)
35 */
36 
37 namespace arduino {
38 
39 // This enumeration provides the lookahead options for parseInt(), parseFloat()
40 // The rules set out here are used until either the first valid character is found
41 // or a time out occurs due to lack of input.
42 enum LookaheadMode{
43  SKIP_ALL, // All invalid characters are ignored.
44  SKIP_NONE, // Nothing is skipped, and the stream is not touched unless the first waiting character is valid.
45  SKIP_WHITESPACE // Only tabs, spaces, line feeds & carriage returns are skipped.
46 };
47 
48 #define NO_IGNORE_CHAR '\x01' // a char not found in a valid ASCII numeric field
49 
50 class Stream : public Print
51 {
52  protected:
53  unsigned long _timeout; // number of milliseconds to wait for the next char before aborting timed read
54  unsigned long _startMillis; // used for timeout measurement
55  int timedRead(); // private method to read stream with timeout
56  int timedPeek(); // private method to peek stream with timeout
57  int peekNextDigit(LookaheadMode lookahead, bool detectDecimal); // returns the next numeric digit in the stream or -1 if timeout
58 
59  public:
60  virtual int available() = 0;
61  virtual int read() = 0;
62  virtual int peek() = 0;
63 
64  Stream() {_timeout=1000;}
65 
66 // parsing methods
67 
68  void setTimeout(unsigned long timeout); // sets maximum milliseconds to wait for stream data, default is 1 second
69  unsigned long getTimeout(void) { return _timeout; }
70 
71  bool find(const char *target); // reads data from the stream until the target string is found
72  bool find(const uint8_t *target) { return find ((const char *)target); }
73  // returns true if target string is found, false if timed out (see setTimeout)
74 
75  bool find(const char *target, size_t length); // reads data from the stream until the target string of given length is found
76  bool find(const uint8_t *target, size_t length) { return find ((const char *)target, length); }
77  // returns true if target string is found, false if timed out
78 
79  bool find(char target) { return find (&target, 1); }
80 
81  bool findUntil(const char *target, const char *terminator); // as find but search ends if the terminator string is found
82  bool findUntil(const uint8_t *target, const char *terminator) { return findUntil((const char *)target, terminator); }
83 
84  bool findUntil(const char *target, size_t targetLen, const char *terminate, size_t termLen); // as above but search ends if the terminate string is found
85  bool findUntil(const uint8_t *target, size_t targetLen, const char *terminate, size_t termLen) {return findUntil((const char *)target, targetLen, terminate, termLen); }
86 
87  long parseInt(LookaheadMode lookahead = SKIP_ALL, char ignore = NO_IGNORE_CHAR);
88  // returns the first valid (long) integer value from the current position.
89  // lookahead determines how parseInt looks ahead in the stream.
90  // See LookaheadMode enumeration at the top of the file.
91  // Lookahead is terminated by the first character that is not a valid part of an integer.
92  // Once parsing commences, 'ignore' will be skipped in the stream.
93 
94  float parseFloat(LookaheadMode lookahead = SKIP_ALL, char ignore = NO_IGNORE_CHAR);
95  // float version of parseInt
96 
97  size_t readBytes( char *buffer, size_t length); // read chars from stream into buffer
98  size_t readBytes( uint8_t *buffer, size_t length) { return readBytes((char *)buffer, length); }
99  // terminates if length characters have been read or timeout (see setTimeout)
100  // returns the number of characters placed in the buffer (0 means no valid data found)
101 
102  size_t readBytesUntil( char terminator, char *buffer, size_t length); // as readBytes with terminator character
103  size_t readBytesUntil( char terminator, uint8_t *buffer, size_t length) { return readBytesUntil(terminator, (char *)buffer, length); }
104  // terminates if length characters have been read, timeout, or if the terminator character detected
105  // returns the number of characters placed in the buffer (0 means no valid data found)
106 
107  // Arduino String functions to be added here
108  String readString();
109  String readStringUntil(char terminator);
110 
111  protected:
112  long parseInt(char ignore) { return parseInt(SKIP_ALL, ignore); }
113  float parseFloat(char ignore) { return parseFloat(SKIP_ALL, ignore); }
114  // These overload exists for compatibility with any class that has derived
115  // Stream and used parseFloat/Int with a custom ignore character. To keep
116  // the public API simple, these overload remains protected.
117 
118  struct MultiTarget {
119  const char *str; // string you're searching for
120  size_t len; // length of string you're searching for
121  size_t index; // index used by the search routine.
122  };
123 
124  // This allows you to search for an arbitrary number of strings.
125  // Returns index of the target that is found first or -1 if timeout occurs.
126  int findMulti(struct MultiTarget *targets, int tCount);
127 };
128 
129 #undef NO_IGNORE_CHAR
130 
131 }
Definition: Print.h:35
Definition: Stream.h:51
Definition: Stream.h:118