添加rtthread相关代码

riscv/rtthread/components/lwp/lwp_itimer.c

@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2006-2023, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2023-11-30     Shell        Add itimer support
+ */
+
+#define _GNU_SOURCE
+#include <sys/time.h>
+#undef _GNU_SOURCE
+
+#define DBG_TAG "lwp.signal"
+#define DBG_LVL DBG_INFO
+#include <rtdbg.h>
+
+#include <rthw.h>
+#include <rtthread.h>
+#include <string.h>
+
+#include "lwp_internal.h"
+#include "sys/signal.h"
+#include "syscall_generic.h"
+
+rt_err_t lwp_signal_setitimer(rt_lwp_t lwp, int which, const struct itimerspec *restrict new, struct itimerspec *restrict old)
+{
+    rt_err_t rc = RT_EOK;
+    timer_t timerid = 0;
+    int flags = 0;
+
+    if (lwp->signal.real_timer == LWP_SIG_INVALID_TIMER)
+    {
+        struct sigevent sevp = {
+            .sigev_signo = SIGALRM,
+            .sigev_notify = SIGEV_SIGNAL,
+        };
+
+        rc = timer_create(CLOCK_REALTIME_ALARM, &sevp, &timerid);
+        if (rc == RT_EOK)
+        {
+            RT_ASSERT(timerid != LWP_SIG_INVALID_TIMER);
+            lwp->signal.real_timer = timerid;
+        }
+        else
+        {
+            /* failed to create timer */
+        }
+    }
+    else
+    {
+        timerid = lwp->signal.real_timer;
+    }
+
+    if (rc == RT_EOK)
+    {
+        switch (which)
+        {
+            case ITIMER_REAL:
+                rc = timer_settime(timerid, flags, new, old);
+                break;
+            default:
+                rc = -ENOSYS;
+                LOG_W("%s() unsupported timer", __func__);
+                break;
+        }
+    }
+
+    return rc;
+}