core headers: Add C++ linker compatibility

core/include/esp/hwrand.h

@@ -13,10 +13,18 @@
 #include <stdint.h>
 #include <sys/types.h>
 
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
 /* Return a random 32-bit number */
 uint32_t hwrand(void);
 
 /* Fill a variable size buffer with data from the Hardware RNG */
 void hwrand_fill(uint8_t *buf, size_t len);
 
+#ifdef	__cplusplus
+}
+#endif
+
 #endif

core/include/esp/iomux.h

@@ -11,6 +11,10 @@
 #include "esp/types.h"
 #include "esp/iomux_regs.h"
 
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
 /**
  * Convert a GPIO pin number to an iomux register index.
  *
@@ -64,4 +68,8 @@ inline static void iomux_set_gpio_function(const uint8_t gpio_number, const uint
    declared above */
 #include "esp/iomux_private.h"
 
+#ifdef	__cplusplus
+}
+#endif
+
 #endif

core/include/esp/rom.h

@@ -5,9 +5,12 @@
  */
 #ifndef _ESP_ROM_H
 #define _ESP_ROM_H
-
 #include <stdint.h>
 
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
 void Cache_Read_Disable(void);
 
 /* http://esp8266-re.foogod.com/wiki/Cache_Read_Enable
@@ -18,4 +21,8 @@ void Cache_Read_Disable(void);
  */
 void Cache_Read_Enable(uint32_t odd_even, uint32_t mb_count, uint32_t no_idea);
 
+#ifdef	__cplusplus
+}
+#endif
+
 #endif

core/include/esp/timer.h

@@ -14,6 +14,10 @@
 #include "esp/timer_regs.h"
 #include "esp/cpu.h"
 
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
 typedef enum {
     FRC1 = 0,
     FRC2 = 1,
@@ -129,4 +133,8 @@ INLINED bool timer_set_timeout(const timer_frc_t frc, uint32_t us);
 
 #include "timer_private.h"
 
+#ifdef	__cplusplus
+}
+#endif
+
 #endif

core/include/esp/timer_private.h

@@ -7,6 +7,10 @@
 #ifndef _ESP_TIMER_PRIVATE_H
 #define _ESP_TIMER_PRIVATE_H
 
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
 #include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -255,6 +259,8 @@ INLINED bool timer_set_timeout(const timer_frc_t frc, uint32_t us)
         return _timer_set_timeout_runtime(frc, us);
 }
 
-
+#ifdef	__cplusplus
+}
+#endif
 
 #endif