all: Unify header guard usage.

The code conventions suggest using header guards, but do not define how
those should look like and instead point to existing files. However, not
all existing files follow the same scheme, sometimes omitting header guards
altogether, sometimes using non-standard names, making it easy to
accidentally pick a "wrong" example.

This commit ensures that all header files of the MicroPython project (that
were not simply copied from somewhere else) follow the same pattern, that
was already present in the majority of files, especially in the py folder.

The rules are as follows.

Naming convention:
* start with the words MICROPY_INCLUDED
* contain the full path to the file
* replace special characters with _

In addition, there are no empty lines before #ifndef, between #ifndef and
one empty line before #endif. #endif is followed by a comment containing
the name of the guard macro.

py/grammar.h cannot use header guards by design, since it has to be
included multiple times in a single C file. Several other files also do not
need header guards as they are only used internally and guaranteed to be
included only once:
* MICROPY_MPHALPORT_H
* mpconfigboard.h
* mpconfigport.h
* mpthreadport.h
* pin_defs_*.h
* qstrdefs*.h

4 files changed, 11 insertions, 10 deletions

diff --git a/pic16bit/board.h b/pic16bit/board.h
index 0eb022436..f79dd3497 100644
--- a/pic16bit/board.h
+++ b/pic16bit/board.h
@@ -23,8 +23,8 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
-#ifndef __MICROPY_INCLUDED_PIC16BIT_BOARD_H__
-#define __MICROPY_INCLUDED_PIC16BIT_BOARD_H__
+#ifndef MICROPY_INCLUDED_PIC16BIT_BOARD_H
+#define MICROPY_INCLUDED_PIC16BIT_BOARD_H
 
 void cpu_init(void);
 
@@ -40,4 +40,4 @@ int uart_rx_any(void);
 int uart_rx_char(void);
 void uart_tx_char(int chr);
 
-#endif // __MICROPY_INCLUDED_PIC16BIT_BOARD_H__
+#endif // MICROPY_INCLUDED_PIC16BIT_BOARD_H
diff --git a/pic16bit/modpyb.h b/pic16bit/modpyb.h
index 6c68cbdfd..910ec1b6e 100644
--- a/pic16bit/modpyb.h
+++ b/pic16bit/modpyb.h
@@ -23,11 +23,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
-#ifndef __MICROPY_INCLUDED_PIC16BIT_MODPYB_H__
-#define __MICROPY_INCLUDED_PIC16BIT_MODPYB_H__
+#ifndef MICROPY_INCLUDED_PIC16BIT_MODPYB_H
+#define MICROPY_INCLUDED_PIC16BIT_MODPYB_H
 
 extern const mp_obj_type_t pyb_led_type;
 extern const mp_obj_type_t pyb_switch_type;
 extern const mp_obj_module_t pyb_module;
 
-#endif // __MICROPY_INCLUDED_PIC16BIT_MODPYB_H__
+#endif // MICROPY_INCLUDED_PIC16BIT_MODPYB_H
diff --git a/pic16bit/pic16bit_mphal.h b/pic16bit/pic16bit_mphal.h
index a858f7e0f..ffcca41bf 100644
--- a/pic16bit/pic16bit_mphal.h
+++ b/pic16bit/pic16bit_mphal.h
@@ -23,13 +23,9 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
-#ifndef __MICROPY_INCLUDED_PIC16BIT_PIC16BIT_MPHAL_H__
-#define __MICROPY_INCLUDED_PIC16BIT_PIC16BIT_MPHAL_H__
 
 #include "py/mpstate.h"
 
 void mp_hal_init(void);
 
 void mp_hal_set_interrupt_char(int c);
-
-#endif // __MICROPY_INCLUDED_PIC16BIT_PIC16BIT_MPHAL_H__
diff --git a/pic16bit/unistd.h b/pic16bit/unistd.h
index cdd9fe061..5b60c8a62 100644
--- a/pic16bit/unistd.h
+++ b/pic16bit/unistd.h
@@ -1,5 +1,10 @@
+#ifndef MICROPY_INCLUDED_PIC16BIT_UNISTD_H
+#define MICROPY_INCLUDED_PIC16BIT_UNISTD_H
+
 // XC16 compiler doesn't seem to have unistd.h file
 
 #define SEEK_CUR 1
 
 typedef int ssize_t;
+
+#endif // MICROPY_INCLUDED_PIC16BIT_UNISTD_H