StreamOutput.h

00001 /*
00002       This file is part of Smoothie (http://smoothieware.org/). The motion control part is heavily based on Grbl (https://github.com/simen/grbl).
00003       Smoothie is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
00004       Smoothie is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
00005       You should have received a copy of the GNU General Public License along with Smoothie. If not, see <http://www.gnu.org/licenses/>.
00006 */
00007 
00008 #ifndef STREAMOUTPUT_H
00009 #define STREAMOUTPUT_H
00010 
00011 #include <stdarg.h>
00012 #include <string.h>
00013 #include <stdio.h>
00014 
00015 // This is a base class for all StreamOutput objects.
00016 // StreamOutputs are basically "things you can sent strings to". They are passed along with gcodes for example so modules can answer to those gcodes.
00017 // They are usually associated with a command source, but can also be a NullStreamOutput if we just want to ignore whatever is sent
00018 
00019 class NullStreamOutput;
00020 
00021 class StreamOutput {
00022     public:
00023         StreamOutput(){}
00024         virtual ~StreamOutput(){}
00025 
00026         virtual int printf(const char* format, ...) __attribute__ ((format(printf, 2, 3))) {
00027             char b[64];
00028             char *buffer;
00029             // Make the message
00030             va_list args;
00031             va_start(args, format);
00032 
00033             int size = vsnprintf(b, 64, format, args)
00034                 + 1; // we add one to take into account space for the terminating \0
00035 
00036             if (size < 64)
00037                 buffer = b;
00038             else
00039             {
00040                 buffer = new char[size];
00041                 vsnprintf(buffer, size, format, args);
00042             }
00043             va_end(args);
00044 
00045             puts(buffer);
00046 
00047             if (buffer != b)
00048                 delete[] buffer;
00049 
00050             return size - 1;
00051         }
00052         virtual int _putc(int c) { return 1; }
00053         virtual int _getc(void) { return 0; }
00054         virtual int puts(const char* str) = 0;
00055 
00056         static NullStreamOutput NullStream;
00057 };
00058 
00059 class NullStreamOutput : public StreamOutput {
00060     public:
00061         int puts(const char* str) { return strlen(str); }
00062 };
00063 
00064 #endif