Revise system headers / enforce c11 (#1695)

!!! Breaking Change !!!
----
All Sming based applications used to have a user_config.h file inside of the application `include/` directory. If your application user_config.h is the same as the one coming from the Sming then make sure to delete it .

If you don't want to delete it most probably the compilation will break with similar error message:
```
include/user_config.h:26:40: fatal error: espinc/c_types_compatible.h: No such file or directory
  #include <espinc/c_types_compatible.h>
```

Replace ` #include <espinc/c_types_compatible.h>` with `include <c_types.h>` to fix this issue.
-----

This PR includes the following changes:
* Standardise data types
* Use `uint32_t` in preference to `uint32`, etc.
* Arduino libraries use a mixture so still need to maintain definitions for those
* Build `C` files within modules to c11 standard (previously defaulted to `gnu90`)
* Move `espinc\c_types_compatible.h` -> `c_types.h`
* Simplify and tidy Esp8266 system headers
* Rename `espinc/c_types_compatible.h` as `c_types.h`, revise to use `stdint` and `stdbool` definitions
* Place location for `c_types.h` and `mem.h` ahead of SDK version in makefiles
* Move system definitions from `user_config.h` into `esp_systemapi.h` (exclude LWIP)
* Don't #include `user_config.h` from `esp_systemapi.h`
* Move missing memory API definitions out of `esp_systemapi.h` and into `mem.h`
* Simplify other headers
* Fix samples - use <esp_systemapi.h> to ensure correct c_types.h gets used
* Move attribute definitions and macros out of ctypes.h
* Add `WEAK_ATTR` macro to allow selective weak symbol support
* Not a C/C++ standard feature and not consistently applied on all platforms, so avoid where possible.

Sming/Arch/Esp8266/Components/axtls-8266/axtls-8266.patch

@@ -1,7 +1,7 @@
 diff -Nuar a/replacements/libc.c b/replacements/libc.c
 --- a/replacements/libc.c   1970-01-01 01:00:00.000000000 +0100
 +++ b/replacements/libc.c   2016-11-21 11:03:47.152184514 +0100
-@@ -0,0 +1,29 @@
+@@ -0,0 +1,28 @@
 +/*
 + libc_replacements.c - replaces libc functions with functions
 + from Espressif SDK
@@ -21,8 +21,7 @@ diff -Nuar a/replacements/libc.c b/replacements/libc.c
 + Modified 03 April 2015 by Markus Sattler
 + */
 +
-+#include <stdint.h>
-+#include "espinc/c_types_compatible.h"
++#include <c_types.h>
 +#include <stdarg.h>
 +
 +extern int ets_putc(int);

Sming/Arch/Esp8266/Components/esp8266/crash_handler.c

@@ -31,7 +31,7 @@ extern void __custom_crash_callback( struct rst_info * rst_info, uint32_t stack,
 extern void custom_crash_callback( struct rst_info * rst_info, uint32_t stack, uint32_t stack_end ) __attribute__ ((weak, alias("__custom_crash_callback")));
 
 void __wrap_system_restart_local() {
-    register uint32_t sp_reg asm("a1");
+    register uint32_t sp_reg __asm__("a1");
     uint32_t sp = sp_reg;
 
     struct rst_info rst_info = {0};

Sming/Arch/Esp8266/Components/esp8266/esp_cplusplus.cpp

@@ -2,6 +2,9 @@
 #include "include/esp_cplusplus.h"
 #include <stdlib.h>
 
+extern void (*__init_array_start)();
+extern void (*__init_array_end)();
+
 ////////////////////////////////////////////////////////////////////////
 
 // Just do it! :)

Sming/Arch/Esp8266/Components/esp8266/include/c_types.h

@@ -0,0 +1,40 @@
+/*
+ *  Copyright (c) 2010 - 2011 Espressif System
+ *
+ */
+
+// Overrides c_types.h for all SDK versions
+
+#ifndef _C_TYPES_H_
+#define _C_TYPES_H_
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdbool.h>
+
+#define BOOL bool
+#define TRUE true
+#define FALSE false
+
+typedef uint8_t         uint8;
+typedef uint8_t         u8;
+typedef int8_t          sint8;
+typedef int8_t          int8;
+typedef int8_t          s8;
+typedef uint16_t        uint16;
+typedef uint16_t        u16;
+typedef int16_t         sint16;
+typedef int16_t         s16;
+typedef uint32_t        uint32;
+typedef unsigned int    u_int;
+typedef uint32_t        u32;
+typedef int32_t         sint32;
+typedef int32_t         s32;
+typedef int32_t         int32;
+typedef int64_t         sint64;
+typedef uint64_t        uint64;
+typedef uint64_t        u64;
+typedef float           real32;
+typedef double          real64;
+
+#endif /* _C_TYPES_H_ */

Sming/Arch/Esp8266/Components/esp8266/include/esp_attr.h

@@ -0,0 +1,25 @@
+// ESP8266 attribute definitions (previously in c_types.h)
+#pragma once
+
+#define IRAM_ATTR __attribute__((section(".iram.text")))
+#define STORE_TYPEDEF_ATTR __attribute__((aligned(4),packed))
+#define STORE_ATTR __attribute__((aligned(4)))
+
+#define DMEM_ATTR __attribute__((section(".bss")))
+#define SHMEM_ATTR
+
+#ifdef ICACHE_FLASH
+#define ICACHE_FLASH_ATTR __attribute__((section(".irom0.text")))
+#define ICACHE_RODATA_ATTR __attribute__((section(".irom.text")))
+#else
+#define ICACHE_FLASH_ATTR
+#define ICACHE_RODATA_ATTR
+#endif
+
+#define STORE_ATTR __attribute__((aligned(4)))
+
+#ifdef ENABLE_GDB
+	#define GDB_IRAM_ATTR IRAM_ATTR
+#else
+	#define GDB_IRAM_ATTR
+#endif

Sming/Arch/Esp8266/Components/esp8266/include/esp_cplusplus.h

@@ -10,15 +10,4 @@
 
 #pragma once
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-	#include "esp_systemapi.h"
-#ifdef __cplusplus
-}
-#endif
-
-extern void (*__init_array_start)(void);
-extern void (*__init_array_end)(void);
-
 void cpp_core_initialize();

Sming/Arch/Esp8266/Components/esp8266/include/esp_systemapi.h

@@ -12,45 +12,52 @@
 
 #pragma once
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// ESP SDK config
+#define LWIP_OPEN_SRC
+#define USE_US_TIMER
+
+// Default types
+#define __CORRECT_ISO_CPP_STDLIB_H_PROTO
+#include <limits.h>
+#include "c_types.h"
+
+// Remove buggy espconn
+#define _NO_ESPCON_
+
+/* Omitted from early SDK versions, in c_types.h in later versions (note: we don't use the SDK c_types.h) */
+typedef enum {
+    OK = 0,
+    FAIL,
+    PENDING,
+    BUSY,
+    CANCEL,
+} STATUS;
+
+#include <sming_attr.h>
+#include "esp_attr.h"
 #include <ets_sys.h>
 #include <osapi.h>
 #include <gpio.h>
 #include <os_type.h>
 #include <user_interface.h>
-#include <spi_flash.h>
 #include <espconn.h>
-#include "espinc/spi_register.h"
-
-#include <stdarg.h>
-
-#include <user_config.h>
 
 #include "m_printf.h"
 #include "debug_progmem.h"
 #include "stringutil.h"
 
 #define __ESP8266_EX__ // System definition ESP8266 SOC
 
-#define IRAM_ATTR __attribute__((section(".iram.text")))
-#define __forceinline __attribute__((always_inline)) inline
-#define STORE_TYPEDEF_ATTR __attribute__((aligned(4),packed))
-#define STORE_ATTR __attribute__((aligned(4)))
-
-/*
- * Use this definition in the cases where a function or a variable is meant to be possibly unused. GCC will not produce a warning for it.
- */
-#define SMING_UNUSED  __attribute__((unused))
+#define LOCAL           static
 
-/*
- * Flags a compiler warning when Sming framework methods, functions or types are changed
- */
-#define SMING_DEPRECATED __attribute__((deprecated))
+#define BIT(nr)         (1UL << (nr))
 
-#ifdef ENABLE_GDB
-	#define GDB_IRAM_ATTR IRAM_ATTR
-#else
-	#define GDB_IRAM_ATTR
-#endif
+#define REG_SET_BIT(_r, _b)  (*(volatile uint32_t*)(_r) |= (_b))
+#define REG_CLR_BIT(_r, _b)  (*(volatile uint32_t*)(_r) &= ~(_b))
 
 #undef assert
 #ifdef SMING_RELEASE
@@ -100,12 +107,6 @@ extern int os_printf_plus(const char *format, ...)  __attribute__ ((format (prin
 extern int os_snprintf(char *str, size_t size, const char *format, ...) __attribute__ ((format (printf, 3, 4)));
 extern int ets_vsnprintf(char * s, size_t n, const char * format, va_list arg) __attribute__ ((format (printf, 3, 0)));
 
-extern void *pvPortMalloc(size_t xWantedSize, const char *file, uint32 line);
-extern void *pvPortZalloc(size_t xWantedSize, const char *file, uint32 line);
-extern void pvPortFree(void *ptr);
-extern void vPortFree(void *ptr, const char *file, uint32 line);
-extern void *vPortMalloc(size_t xWantedSize);
-
 extern void ets_intr_lock();
 extern void ets_intr_unlock();
 
@@ -123,3 +124,7 @@ extern void xt_enable_interrupts();
 
 extern void ets_isr_mask(unsigned intr);
 extern void ets_isr_unmask(unsigned intr);
+
+#ifdef __cplusplus
+}
+#endif

Sming/Arch/Esp8266/Components/esp8266/include/mem.h

@@ -0,0 +1,23 @@
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef SDK_INTERNAL
+
+// Missing from early SDK versions
+extern void *pvPortMalloc(size_t xWantedSize, const char *file, uint32 line);
+extern void *pvPortZalloc(size_t xWantedSize, const char *file, uint32 line);
+extern void pvPortFree(void *ptr);
+extern void vPortFree(void *ptr, const char *file, uint32 line);
+extern void *vPortMalloc(size_t xWantedSize);
+
+#endif
+
+#include_next <mem.h>
+
+#ifdef __cplusplus
+}
+#endif
+

Sming/Arch/Esp8266/Components/esp8266/startup.cpp

@@ -12,10 +12,11 @@
 #include "Platform/System.h"
 #include <driver/uart.h>
 #include <gdb/gdb_hooks.h>
+#include <esp_cplusplus.h>
 
 extern void init();
 
-extern "C" void  __attribute__((weak)) user_init(void)
+extern "C" void  WEAK_ATTR user_init(void)
 {
 	// We want high resolution timing - see HardwareTimer class
 	system_timer_reinit();
@@ -40,7 +41,7 @@ extern "C" void  __attribute__((weak)) user_init(void)
 }
 
 // For compatibility with SDK v1.1
-extern "C" void __attribute__((weak)) user_rf_pre_init(void)
+extern "C" void WEAK_ATTR user_rf_pre_init(void)
 {
 	// RTC startup fix, author pvvx
     volatile uint32 * ptr_reg_rtc_ram = (volatile uint32 *)0x60001000;
@@ -50,7 +51,7 @@ extern "C" void __attribute__((weak)) user_rf_pre_init(void)
     }
 }
 
-extern "C" uint32 ICACHE_FLASH_ATTR  __attribute__((weak)) user_rf_cal_sector_set(void)
+extern "C" uint32 ICACHE_FLASH_ATTR  WEAK_ATTR user_rf_cal_sector_set(void)
 {
     enum flash_size_map size_map = system_get_flash_size_map();
     uint32 rf_cal_sec = 0;
@@ -88,7 +89,7 @@ extern "C" uint32 ICACHE_FLASH_ATTR  __attribute__((weak)) user_rf_cal_sector_se
 
 #if defined(ESP_SDK_VERSION_MAJOR) and ESP_SDK_VERSION_MAJOR>=3
 
-extern "C" void ICACHE_FLASH_ATTR  __attribute__((weak)) user_pre_init(void)
+extern "C" void ICACHE_FLASH_ATTR WEAK_ATTR user_pre_init(void)
 {
 	const uint32_t MAX_PROGRAM_SECTORS = 0x100000 / SPI_FLASH_SEC_SIZE; // 1MB addressable
 
@@ -128,7 +129,7 @@ extern "C" void ICACHE_FLASH_ATTR  __attribute__((weak)) user_pre_init(void)
 #endif /* defined(ESP_SDK_VERSION_MAJOR) and ESP_SDK_VERSION_MAJOR>=3 */
 
 namespace std {
-    void __attribute__((weak)) __throw_bad_function_call()
+    void WEAK_ATTR __throw_bad_function_call()
     {
         while(1);
     };