✨ 064 printf

docs/10 用户程序/064 printf.md

@@ -0,0 +1,10 @@
+# printf
+
+## 系统调用 write
+
+```c++
+int32 write(fd_t fd, char *buf, u32 len);
+```
+
+- kmalloc
+- kfree

src/include/onix/console.h

@@ -5,6 +5,6 @@
 
 void console_init();
 void console_clear();
-void console_write(char *buf, u32 count);
+int32 console_write(char *buf, u32 count);
 
 #endif

src/include/onix/stdio.h

@@ -5,5 +5,6 @@
 
 int vsprintf(char *buf, const char *fmt, va_list args);
 int sprintf(char *buf, const char *fmt, ...);
+int printf(const char *fmt, ...);
 
 #endif

src/include/onix/syscall.h

@@ -6,6 +6,7 @@
 typedef enum syscall_t
 {
     SYS_NR_TEST,
+    SYS_NR_WRITE,
     SYS_NR_SLEEP,
     SYS_NR_YIELD,
 } syscall_t;
@@ -14,4 +15,6 @@ u32 test();
 void yield();
 void sleep(u32 ms);
 
+int32 write(fd_t fd, char *buf, u32 len);
+
 #endif

src/include/onix/types.h

@@ -38,4 +38,12 @@ typedef unsigned long long u64;
 typedef u32 time_t;
 typedef u32 idx_t;
 
+typedef int32 fd_t;
+typedef enum std_fd_t
+{
+    stdin,
+    stdout,
+    stderr,
+} std_fd_t;
+
 #endif

src/kernel/console.c

@@ -155,12 +155,13 @@ static void command_del()
 
 extern void start_beep();
 
-void console_write(char *buf, u32 count)
+int32 console_write(char *buf, u32 count)
 {
     bool intr = interrupt_disable(); // 禁止中断
 
     char ch;
-    while (count--)
+    int32 nr = 0;
+    while (nr++ < count)
     {
         ch = *buf++;
         switch (ch)
@@ -211,6 +212,7 @@ void console_write(char *buf, u32 count)
 
     // 恢复中断
     set_interrupt_state(intr);
+    return nr;
 }
 
 void console_init()

src/kernel/gate.c

@@ -3,6 +3,7 @@
 #include <onix/debug.h>
 #include <onix/syscall.h>
 #include <onix/task.h>
+#include <onix/console.h>
 
 #define LOGK(fmt, args...) DEBUGK(fmt, ##args)
 
@@ -45,6 +46,17 @@ static u32 sys_test()
     return 255;
 }
 
+int32 sys_write(fd_t fd, char *buf, u32 len)
+{
+    if (fd == stdout || fd == stderr)
+    {
+        return console_write(buf, len);
+    }
+    // todo
+    panic("write!!!!");
+    return 0;
+}
+
 void syscall_init()
 {
     for (size_t i = 0; i < SYSCALL_SIZE; i++)
@@ -55,4 +67,6 @@ void syscall_init()
     syscall_table[SYS_NR_TEST] = sys_test;
     syscall_table[SYS_NR_SLEEP] = task_sleep;
     syscall_table[SYS_NR_YIELD] = task_yield;
+
+    syscall_table[SYS_NR_WRITE] = sys_write;
 }

src/kernel/thread.c

@@ -2,6 +2,7 @@
 #include <onix/syscall.h>
 #include <onix/debug.h>
 #include <onix/task.h>
+#include <onix/stdio.h>
 
 #define LOGK(fmt, args...) DEBUGK(fmt, ##args)
 
@@ -31,7 +32,8 @@ static void real_init_thread()
         // asm volatile("in $0x92, %ax\n");
         sleep(100);
         // LOGK("%c\n", ch);
-        // printk("%c", ch);
+        // printk("task is in user mode %d\n", counter++);
+        printf("task is in user mode %d\n", counter++);
     }
 }
 

src/lib/printf.c

@@ -0,0 +1,26 @@
+/* (C) Copyright 2022 Steven;
+* @author: Steven [email protected]
+* @date: 2022-06-28
+*/
+
+#include <onix/stdarg.h>
+#include <onix/stdio.h>
+#include <onix/syscall.h>
+
+static char buf[1024];
+
+int printf(const char *fmt, ...)
+{
+    va_list args;
+    int i;
+
+    va_start(args, fmt);
+
+    i = vsprintf(buf, fmt, args);
+
+    va_end(args);
+
+    write(stdout, buf, i);
+
+    return i;
+}

src/lib/syscall.c

@@ -20,6 +20,26 @@ static _inline u32 _syscall1(u32 nr, u32 arg)
     return ret;
 }
 
+static _inline u32 _syscall2(u32 nr, u32 arg1, u32 arg2)
+{
+    u32 ret;
+    asm volatile(
+        "int $0x80\n"
+        : "=a"(ret)
+        : "a"(nr), "b"(arg1), "c"(arg2));
+    return ret;
+}
+
+static _inline u32 _syscall3(u32 nr, u32 arg1, u32 arg2, u32 arg3)
+{
+    u32 ret;
+    asm volatile(
+        "int $0x80\n"
+        : "=a"(ret)
+        : "a"(nr), "b"(arg1), "c"(arg2), "d"(arg3));
+    return ret;
+}
+
 u32 test()
 {
     return _syscall0(SYS_NR_TEST);
@@ -33,4 +53,9 @@ void yield()
 void sleep(u32 ms)
 {
     _syscall1(SYS_NR_SLEEP, ms);
+}
+
+int32 write(fd_t fd, char *buf, u32 len)
+{
+    return _syscall3(SYS_NR_WRITE, fd, (u32)buf, len);
 }

src/makefile

@@ -62,6 +62,7 @@ $(BUILD)/kernel.bin: \
 	$(BUILD)/lib/vsprintf.o \
 	$(BUILD)/lib/stdlib.o \
 	$(BUILD)/lib/syscall.o \
+	$(BUILD)/lib/printf.o \
 
 	$(shell mkdir -p $(dir $@))
 	ld ${LDFLAGS} $^ -o $@