串口环形缓冲区强化：单独单写及最小临界区修改

Src/uart_ring_buffer.c

@@ -6,12 +6,25 @@
  * @ingroup RingBuffer
  */
 #include "uart_ring_buffer.h"
+#include "gd32e23x.h"
 
 static volatile uint8_t uart_rx_buffer[UART_RX_BUFFER_SIZE];
 static volatile uint8_t write_index = 0;
 static volatile uint8_t read_index = 0;
 static volatile uint32_t dropped_bytes = 0;
 
+static inline uint32_t irq_save(void) {
+    uint32_t primask = __get_PRIMASK();
+    __disable_irq();
+    return primask;
+}
+
+static inline void irq_restore(uint32_t primask) {
+    if (primask == 0U) {
+        __enable_irq();
+    }
+}
+
 /**
  * @brief 重置环形缓冲区状态。
  * @details 将读指针、写指针与丢弃计数清零，不清空数据区内容。
@@ -31,7 +44,9 @@ static void uart_ring_buffer_reset_state(void) {
  * @ingroup RingBuffer
  */
 void uart_ring_buffer_init(void) {
+    uint32_t irq_key = irq_save();
     uart_ring_buffer_reset_state();
+    irq_restore(irq_key);
 }
 
 /**
@@ -90,7 +105,9 @@ bool uart_ring_buffer_put(uint8_t data) {
  * @ingroup RingBuffer
  */
 void uart_ring_buffer_clear(void) {
+    uint32_t irq_key = irq_save();
     uart_ring_buffer_reset_state();
+    irq_restore(irq_key);
 }
 
 /**