From 90436a4f46dec5ce3cc341e981b9aaf9f4e79605 Mon Sep 17 00:00:00 2001
From: Mathieu Maret <mathieu@mathux.org>
Date: Wed, 14 Feb 2024 18:43:47 +0100
Subject: [PATCH] Add usleep syscall

---
 core/syscall.c             | 12 +++++++++++-
 core/syscall.h             |  1 +
 core/thread.c              | 11 ++++++++---
 core/thread.h              |  1 +
 userspace/kernel/syscall.h |  1 +
 userspace/libc.c           |  5 +++++
 userspace/main_user.c      |  2 ++
 userspace/unistd.h         |  4 ++++
 8 files changed, 33 insertions(+), 4 deletions(-)
 create mode 100644 userspace/unistd.h

diff --git a/core/syscall.c b/core/syscall.c
index 288d5a7..5a5151f 100644
--- a/core/syscall.c
+++ b/core/syscall.c
@@ -11,7 +11,6 @@
 #include "uaddrspace.h"
 #include "zero.h"
 
-
 int syscallExecute(int syscallId, const struct cpu_state *userCtx)
 {
 
@@ -146,6 +145,17 @@ int syscallExecute(int syscallId, const struct cpu_state *userCtx)
 
             break;
         }
+        case SYSCALL_ID_USLEEP: {
+            unsigned int sleep;
+
+            ret = syscallGet1arg(userCtx, &sleep);
+            if (ret)
+                break;
+
+            ret = threadUsleep(sleep);
+
+            break;
+        }
         default:
             printf("Unknon syscall id %d\n", syscallId);
             ret = -ENOENT;
diff --git a/core/syscall.h b/core/syscall.h
index 72ccf9e..53cfa05 100644
--- a/core/syscall.h
+++ b/core/syscall.h
@@ -12,6 +12,7 @@
 #define SYSCALL_ID_MMAP 7
 #define SYSCALL_ID_MUNMAP 8
 #define SYSCALL_ID_NEW_THREAD 9
+#define SYSCALL_ID_USLEEP 10
 
 #ifdef __KERNEL__
 int syscallExecute(int syscallId, const struct cpu_state *user_ctx);
diff --git a/core/thread.c b/core/thread.c
index ae0f293..cbb55af 100644
--- a/core/thread.c
+++ b/core/thread.c
@@ -292,6 +292,11 @@ int threadYield()
 }
 
 int threadMsleep(unsigned long msec)
+{
+    return threadUsleep(msec*1000);
+}
+
+int threadUsleep(unsigned long usec)
 {
     uint32_t flags;
     struct thread *next, *current;
@@ -299,12 +304,12 @@ int threadMsleep(unsigned long msec)
     disable_IRQs(flags);
 
     current = currentThread;
-    assertmsg(current->state == RUNNING, "thread %s is in state %d for %lu\n", current->name,
-              current->state, msec);
+    assertmsg(current->state == RUNNING, "thread %s is in state %d for %lu us\n", current->name,
+              current->state, usec);
 
     current->state              = SLEEPING;
     current->sleepHaveTimeouted = 0;
-    current->jiffiesSleeping    = msecs_to_jiffies(msec);
+    current->jiffiesSleeping    = usecs_to_jiffies(usec);
     next                        = threadSelectNext();
 
     assert(next != current);
diff --git a/core/thread.h b/core/thread.h
index 0997676..6da8cd7 100644
--- a/core/thread.h
+++ b/core/thread.h
@@ -83,6 +83,7 @@ int threadYield();
 int threadWait(struct thread *current, struct thread *next, unsigned long msec);
 int threadUnsched(struct thread *th);
 int threadMsleep(unsigned long msec);
+int threadUsleep(unsigned long usec);
 int threadOnJieffiesTick();
 struct thread *getCurrentThread();
 int threadAddThread(struct thread *th);
diff --git a/userspace/kernel/syscall.h b/userspace/kernel/syscall.h
index 72ccf9e..53cfa05 100644
--- a/userspace/kernel/syscall.h
+++ b/userspace/kernel/syscall.h
@@ -12,6 +12,7 @@
 #define SYSCALL_ID_MMAP 7
 #define SYSCALL_ID_MUNMAP 8
 #define SYSCALL_ID_NEW_THREAD 9
+#define SYSCALL_ID_USLEEP 10
 
 #ifdef __KERNEL__
 int syscallExecute(int syscallId, const struct cpu_state *user_ctx);
diff --git a/userspace/libc.c b/userspace/libc.c
index ff91b25..fa793c2 100644
--- a/userspace/libc.c
+++ b/userspace/libc.c
@@ -5,6 +5,7 @@
 #include "swintr.h"
 #include "sys/mman.h"
 #include "syscall.h"
+#include "unistd.h"
 
 int errno = 0;
 int memcmp(const void *aptr, const void *bptr, size_t size)
@@ -765,3 +766,7 @@ int new_thread(start_routine *func, void *arg, size_t stackSize)
     return syscall4(SYSCALL_ID_NEW_THREAD, (unsigned int)thread_runner, (unsigned int)func,
                     (unsigned int)arg, stackSize);
 }
+
+int usleep(useconds_t usec) {
+    return syscall1(SYSCALL_ID_USLEEP, (unsigned int)usec);
+}
diff --git a/userspace/main_user.c b/userspace/main_user.c
index 7354fdc..88128fd 100644
--- a/userspace/main_user.c
+++ b/userspace/main_user.c
@@ -4,6 +4,7 @@
 #include "stddef.h"
 #include "sys/mman.h"
 #include "tiny.h"
+#include "unistd.h"
 
 int func_help()
 {
@@ -122,6 +123,7 @@ int func_munmap()
 static void *print_hello(void *arg) {
         (void)arg;
         printf("Hello World from thread\n");
+        usleep(100);
 
         return NULL;
 }
diff --git a/userspace/unistd.h b/userspace/unistd.h
new file mode 100644
index 0000000..7d7da70
--- /dev/null
+++ b/userspace/unistd.h
@@ -0,0 +1,4 @@
+#pragma once
+
+typedef unsigned int useconds_t;
+int usleep(useconds_t usec);