Moving write errors out of return value into separate API methods.

write(), print(), println() now return size_t (and don't use negative values to signal errors).
Print adds writeError() for checking for write errors, clearWriteError() to reset the flag to false, and a protected setWriteError() for signalling errors.

http://code.google.com/p/arduino/issues/detail?id=598

1 files changed, 36 insertions, 30 deletions

diff --git a/cores/arduino/Print.h b/cores/arduino/Print.h
index 3f303f3..fce302e 100755
--- a/cores/arduino/Print.h
+++ b/cores/arduino/Print.h
@@ -23,8 +23,6 @@
 #include <inttypes.h>
 #include <stdio.h> // for size_t
 
-typedef int ssize_t;
-
 #include "WString.h"
 #include "Printable.h"
 
@@ -36,37 +34,45 @@ typedef int ssize_t;
 class Print
 {
   private:
-    ssize_t printNumber(unsigned long, uint8_t);
-    ssize_t printFloat(double, uint8_t);
+    int write_error;
+    size_t printNumber(unsigned long, uint8_t);
+    size_t printFloat(double, uint8_t);
+  protected:
+    void setWriteError(int err = 1) { write_error = err; }
   public:
-    virtual ssize_t write(uint8_t) = 0;
-    virtual ssize_t write(const char *str);
-    virtual ssize_t write(const uint8_t *buffer, size_t size);
+    Print() : write_error(0) {}
+  
+    int writeError() { return write_error; }
+    void clearWriteError() { setWriteError(0); }
+  
+    virtual size_t write(uint8_t) = 0;
+    virtual size_t write(const char *str);
+    virtual size_t write(const uint8_t *buffer, size_t size);
     
-    ssize_t print(const __FlashStringHelper *);
-    ssize_t print(const String &);
-    ssize_t print(const char[]);
-    ssize_t print(char);
-    ssize_t print(unsigned char, int = DEC);
-    ssize_t print(int, int = DEC);
-    ssize_t print(unsigned int, int = DEC);
-    ssize_t print(long, int = DEC);
-    ssize_t print(unsigned long, int = DEC);
-    ssize_t print(double, int = 2);
-    ssize_t print(const Printable&);
+    size_t print(const __FlashStringHelper *);
+    size_t print(const String &);
+    size_t print(const char[]);
+    size_t print(char);
+    size_t print(unsigned char, int = DEC);
+    size_t print(int, int = DEC);
+    size_t print(unsigned int, int = DEC);
+    size_t print(long, int = DEC);
+    size_t print(unsigned long, int = DEC);
+    size_t print(double, int = 2);
+    size_t print(const Printable&);
 
-    ssize_t println(const __FlashStringHelper *);
-    ssize_t println(const String &s);
-    ssize_t println(const char[]);
-    ssize_t println(char);
-    ssize_t println(unsigned char, int = DEC);
-    ssize_t println(int, int = DEC);
-    ssize_t println(unsigned int, int = DEC);
-    ssize_t println(long, int = DEC);
-    ssize_t println(unsigned long, int = DEC);
-    ssize_t println(double, int = 2);
-    ssize_t println(const Printable&);
-    ssize_t println(void);
+    size_t println(const __FlashStringHelper *);
+    size_t println(const String &s);
+    size_t println(const char[]);
+    size_t println(char);
+    size_t println(unsigned char, int = DEC);
+    size_t println(int, int = DEC);
+    size_t println(unsigned int, int = DEC);
+    size_t println(long, int = DEC);
+    size_t println(unsigned long, int = DEC);
+    size_t println(double, int = 2);
+    size_t println(const Printable&);
+    size_t println(void);
 };
 
 #endif