blob: 1dfec7379172493580bae14a7c48ab4cc1495ba5 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
|
#include "kernel/syscall.h"
#include "common/types.h"
#include "kernel/proc.h"
#include "kernel/riscv.h"
#include "drivers/uart.h"
#include "kernel/timer.h"
#include "kernel/mm.h"
#include "kernel/trap.h"
extern "C++" int fork();
namespace ProcManager
{
void exit(int status);
int wait(uint64_t addr);
}
static uint64_t argraw(int n)
{
Proc *p = myproc();
switch (n)
{
case 0:
return p->tf->a0;
case 1:
return p->tf->a1;
case 2:
return p->tf->a2;
case 3:
return p->tf->a3;
case 4:
return p->tf->a4;
case 5:
return p->tf->a5;
default:
return static_cast<uint64_t>(-1);
}
}
static int argint(int n, int *ip)
{
*ip = static_cast<int>(argraw(n));
return 0;
}
static uint64_t sys_exit()
{
int n;
if (argint(0, &n) < 0)
return static_cast<uint64_t>(-1);
ProcManager::exit(n);
return 0;
}
static uint64_t sys_fork()
{
return static_cast<uint64_t>(fork());
}
static uint64_t sys_wait()
{
uint64_t p = argraw(0);
return static_cast<uint64_t>(ProcManager::wait(p));
}
static uint64_t sys_getpid()
{
return static_cast<uint64_t>(myproc()->pid);
}
static uint64_t sys_putc()
{
char c = static_cast<char>(argraw(0));
Drivers::uart_putc(c);
return 0;
}
static uint64_t sys_write()
{
int fd;
int n;
uint64_t p;
if (argint(0, &fd) < 0 || argint(2, &n) < 0)
return static_cast<uint64_t>(-1);
p = argraw(1);
// Drivers::uart_puts("DEBUG: sys_write fd=");
// Drivers::uart_put_int(fd);
// Drivers::uart_puts(" len=");
// Drivers::uart_put_int(n);
// Drivers::uart_puts("\n");
if (fd == 1) // stdout
{
Proc *proc = myproc();
constexpr int MAX_WRITE_BUF = 128;
char buf[MAX_WRITE_BUF];
int i = 0;
while (i < n)
{
int len = n - i;
if (len > MAX_WRITE_BUF)
len = MAX_WRITE_BUF;
if (VM::copyin(proc->pagetable, buf, p + i, static_cast<uint64_t>(len)) < 0)
{
Drivers::uart_puts("sys_write: copyin failed\n");
return static_cast<uint64_t>(-1);
}
for (int j = 0; j < len; j++)
{
Drivers::uart_putc(buf[j]);
}
i += len;
}
return static_cast<uint64_t>(n);
}
return static_cast<uint64_t>(-1);
}
void syscall()
{
Proc *p = myproc();
int num = p->tf->a7;
uint64_t ret = static_cast<uint64_t>(-1);
Drivers::uart_puts("Syscall: ");
Drivers::print_hex(num);
Drivers::uart_puts("\n");
switch (num)
{
case SYS_write:
ret = sys_write();
break;
case SYS_putc:
ret = sys_putc();
break;
case SYS_fork:
ret = sys_fork();
break;
case SYS_exit:
ret = sys_exit();
break;
case SYS_wait:
ret = sys_wait();
break;
case SYS_getpid:
ret = sys_getpid();
break;
default:
Drivers::uart_puts("Unknown Syscall ID: ");
Drivers::print_hex(num);
Drivers::uart_puts("\n");
ret = static_cast<uint64_t>(-1);
break;
}
p->tf->a0 = ret;
}
|
