X-Git-Url: https://scm.lunaixsky.com/lunaix-os.git/blobdiff_plain/7515e526342f6ee07cbe92f5a458f1c2c4a1fcaf..f69a7227ff3ad84af3651fe36162e131d4f2b323:/lunaix-os/kernel/demos/iotest.c

diff --git a/lunaix-os/kernel/demos/iotest.c b/lunaix-os/kernel/demos/iotest.c
index 2ddeb1a..643452c 100644
--- a/lunaix-os/kernel/demos/iotest.c
+++ b/lunaix-os/kernel/demos/iotest.c
@@ -1,9 +1,8 @@
 #include <lunaix/fctrl.h>
 #include <lunaix/foptions.h>
+#include <lunaix/lunistd.h>
 #include <lunaix/proc.h>
-#include <lunaix/syslog.h>
-
-LOG_MODULE("IOTEST")
+#include <ulibc/stdio.h>
 
 void
 _iotest_main()
@@ -11,28 +10,56 @@ _iotest_main()
     char test_sequence[] = "Once upon a time, in a magical land of Equestria. "
                            "There were two regal sisters who ruled together "
                            "and created harmony for all the land.";
+    char read_out[256];
+
+    // 切换工作目录至 /dev
+    int errno = chdir("/dev");
+    if (errno) {
+        write(stdout, "fail to chdir", 15);
+        return;
+    }
+
+    if (getcwd(read_out, sizeof(read_out))) {
+        printf("current working dir: %s\n", read_out);
+    }
 
-    int fd = open("/dev/sda", 0);  // bd0 设备 - 硬盘
-    int tty = open("/dev/tty", 0); // tty 设备 - 控制台
+    // sda 设备 - 硬盘
+    //  sda设备属于容积设备（Volumetric Device），
+    //  Lunaix会尽可能缓存任何对此设备的上层读写，并使用延迟写入策略。（FO_DIRECT可用于屏蔽该功能）
+    int fd = open("./sda", 0);
 
-    if (fd < 0 || tty < 0) {
-        kprintf(KERROR "fail to open (%d)\n", geterrno());
+    if (fd < 0) {
+        printf("fail to open (%d)\n", geterrno());
         return;
     }
 
-    // 移动指针至第二个逻辑扇区（LBA=1），并写入
-    lseek(fd, 1, FSEEK_SET);
+    // 移动指针至512字节，在大多数情况下，这是第二个逻辑扇区的起始处
+    lseek(fd, 512, FSEEK_SET);
+
+    // 总共写入 64 * 136 字节，会产生3个页作为缓存
+    for (size_t i = 0; i < 64; i++) {
+        write(fd, test_sequence, sizeof(test_sequence));
+    }
+
+    // 随机读写测试
+    lseek(fd, 4 * 4096, FSEEK_SET);
     write(fd, test_sequence, sizeof(test_sequence));
 
+    printf("input: ");
+    int size = read(stdin, read_out, 256);
+
+    printf("your said: %s\n", read_out);
+
+    write(fd, read_out, size);
+
     // 读出我们写的内容
-    char read_out[256];
-    lseek(fd, -1, FSEEK_CUR);
+    lseek(fd, 512, FSEEK_SET);
     read(fd, read_out, sizeof(read_out));
 
-    write(tty, read_out, sizeof(read_out));
+    // 将读出的内容直接写入tty设备
+    write(stdout, read_out, sizeof(read_out));
+    write(stdout, "\n", 1);
 
+    // 关闭文件，这同时会将页缓存中的数据下发到底层驱动
     close(fd);
-    close(tty);
-
-    kprint_hex(read_out, sizeof(read_out));
 }
\ No newline at end of file