feat(printf): added PRINTF_OVERRIDE_LIBC support

Fixes #16

1 files changed, 24 insertions, 1 deletions

diff --git a/printf.h b/printf.h
index b82e70f..69245cb 100644
--- a/printf.h
+++ b/printf.h
@@ -25,7 +25,7 @@
 // \brief Tiny printf, sprintf and snprintf implementation, optimized for speed on

 //        embedded systems with a very limited resources.

 //        Use this instead of bloated standard/newlib printf.

-//        These routines are thread safe and reentrant!

+//        These routines are thread safe and reentrant.

 //

 ///////////////////////////////////////////////////////////////////////////////

 

@@ -56,6 +56,12 @@ extern "C" {
 void _putchar(char character);

 

 

+// if PRINTF_OVERRIDE_LIBC is is defined, the regular printf() API is overridden by macro defines

+// and internal underscore-appended functions like printf_() are used to avoid conflicts with

+// LIBC defined printf() functions.

+// default: undefined

+#ifndef PRINTF_OVERRIDE_LIBC

+

 /**

  * Tiny printf implementation

  * You have to implement _putchar if you use printf()

@@ -97,6 +103,23 @@ int vsnprintf(char* buffer, size_t count, const char* format, va_list va);
  */

 int fctprintf(void (*out)(char character, void* arg), void* arg, const char* format, ...);

 

+#else   // PRINTF_OVERRIDE_LIBC

+

+// override the LIBC defined function names

+#define printf    printf_

+#define sprintf   sprintf_

+#define snprintf  snprintf_

+#define vsnprintf vsnprintf_

+#define fctprintf fctprintf_

+

+int printf_(const char* format, ...);

+int sprintf_(char* buffer, const char* format, ...);

+int snprintf_(char* buffer, size_t count, const char* format, ...);

+int vsnprintf_(char* buffer, size_t count, const char* format, va_list va);

+int fctprintf_(void (*out)(char character, void* arg), void* arg, const char* format, ...);

+

+#endif  // PRINTF_OVERRIDE_LIBC

+

 

 #ifdef __cplusplus

 }