Merge pull request #19 from mysterywolf/master

增加rt_mb_urgent()例程

zh/mailbox_urgent_sample.c

@@ -0,0 +1,128 @@
+/*
+ * Copyright (c) 2006-2018, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2018-08-24     yangjie      the first version
+ * 2021-01-03     Meco Man     add the demo of rt_mb_urgent()
+ */
+
+/*
+ * 程序清单：邮箱例程
+ *
+ * 这个程序会创建2个动态线程，一个静态的邮箱对象，其中一个线程往邮箱中发送邮件，
+ * 一个线程往邮箱中收取邮件。
+ * 本例程也会展示紧急邮件和正常邮件的区别。
+ */
+#include <rtthread.h>
+
+#define THREAD_PRIORITY      10
+#define THREAD_TIMESLICE     5
+
+/* 邮箱控制块 */
+static struct rt_mailbox mb;
+/* 用于放邮件的内存池 */
+static char mb_pool[128];
+
+static char mb_urgent[] = "I'm a urgent mail!";
+static char mb_normal[] = "I'm a normal mail!";
+static char mb_str3[] = "over";
+
+ALIGN(RT_ALIGN_SIZE)
+static char thread1_stack[1024];
+static struct rt_thread thread1;
+
+/* 线程1入口 */
+static void thread1_entry(void *parameter)
+{
+    char *str;
+
+    while (1)
+    {
+        rt_kprintf("thread1: try to recv a mail\n");
+
+        /* 从邮箱中收取邮件 */
+        if (rt_mb_recv(&mb, (rt_ubase_t *)&str, RT_WAITING_FOREVER) == RT_EOK)
+        {
+            rt_kprintf("thread1: get a mail from mailbox, the content:%s\n", str);
+            if (str == mb_str3)
+                break;
+
+            /* 延时100ms */
+            rt_thread_mdelay(100);
+        }
+    }
+    /* 执行邮箱对象脱离 */
+    rt_mb_detach(&mb);
+}
+
+ALIGN(RT_ALIGN_SIZE)
+static char thread2_stack[1024];
+static struct rt_thread thread2;
+
+/* 线程2入口 */
+static void thread2_entry(void *parameter)
+{
+    rt_uint8_t count;
+
+    count = 0;
+    while (count < 10)
+    {
+        count ++;
+        
+        /* 分别发送正常邮件和紧急邮件到邮箱中 */
+        /* 关调度器是为了同时给线程1两封邮件，观察线程1如何处理紧急邮件和正常邮件 */
+        rt_enter_critical();
+        rt_mb_send(&mb, (rt_uint32_t)&mb_normal);
+        rt_mb_urgent(&mb, (rt_uint32_t)&mb_urgent);
+        rt_exit_critical();
+        /* 可以看到虽然正常邮件和紧急优先同时发送，但是邮箱选择优先处理紧急邮件 */
+
+        /* 延时200ms */
+        rt_thread_mdelay(200);
+    }
+
+    /* 发送邮件告诉线程1，线程2已经运行结束 */
+    rt_mb_send(&mb, (rt_uint32_t)&mb_str3);
+}
+
+int mailbox_urgent_sample(void)
+{
+    rt_err_t result;
+
+    /* 初始化一个mailbox */
+    result = rt_mb_init(&mb,
+                        "mbt",                      /* 名称是mbt */
+                        &mb_pool[0],                /* 邮箱用到的内存池是mb_pool */
+                        sizeof(mb_pool) / sizeof(rt_ubase_t), /* 邮箱中的邮件数目,sizeof(rt_ubase_t)表示指针大小 */
+                        RT_IPC_FLAG_FIFO);          /* 采用FIFO方式进行线程等待 */
+    if (result != RT_EOK)
+    {
+        rt_kprintf("init mailbox failed.\n");
+        return -1;
+    }
+
+    rt_thread_init(&thread1,
+                   "thread1",
+                   thread1_entry,
+                   RT_NULL,
+                   &thread1_stack[0],
+                   sizeof(thread1_stack),
+                   THREAD_PRIORITY, THREAD_TIMESLICE);
+    rt_thread_startup(&thread1);
+
+    rt_thread_init(&thread2,
+                   "thread2",
+                   thread2_entry,
+                   RT_NULL,
+                   &thread2_stack[0],
+                   sizeof(thread2_stack),
+                   THREAD_PRIORITY, THREAD_TIMESLICE);
+    rt_thread_startup(&thread2);
+    return 0;
+}
+
+/* 导出到 msh 命令列表中 */
+MSH_CMD_EXPORT(mailbox_urgent_sample, mailbox urgent sample);