add: start sysinfo for lab two

Makefile

@@ -149,7 +149,8 @@ UPROGS=\
 	$U/_grind\
 	$U/_wc\
 	$U/_zombie\
-	$U/_trace
+	$U/_trace\
+	$U/_sysinfotest
 
 
 

kernel/syscall.c

@@ -105,6 +105,7 @@ extern uint64 sys_wait(void);
 extern uint64 sys_write(void);
 extern uint64 sys_uptime(void);
 extern uint64 sys_trace(void);
+extern uint64 sys_sysinfo(void);
 
 static uint64 (*syscalls[])(void) = {
 [SYS_fork]    sys_fork,
@@ -129,6 +130,7 @@ static uint64 (*syscalls[])(void) = {
 [SYS_mkdir]   sys_mkdir,
 [SYS_close]   sys_close,
 [SYS_trace]   sys_trace,
+[SYS_sysinfo] sys_sysinfo,
 };
 
 // translate from the above system call function names
@@ -155,6 +157,7 @@ static char *syscalls_name[] = {
 [SYS_mkdir]   "mkdir",
 [SYS_close]   "close",
 [SYS_trace]   "trace",
+[SYS_sysinfo] "sysinfo",
 };
 
 void

kernel/syscall.h

@@ -20,4 +20,5 @@
 #define SYS_link   19
 #define SYS_mkdir  20
 #define SYS_close  21
-#define SYS_trace  22
+#define SYS_trace  22
+#define SYS_sysinfo  23

user/user.h

@@ -1,5 +1,6 @@
 struct stat;
 struct rtcdate;
+struct sysinfo;
 
 // system calls
 int fork(void);
@@ -24,6 +25,7 @@ char* sbrk(int);
 int sleep(int);
 int uptime(void);
 int trace(int);
+int sysinfo(struct sysinfo *);
 
 // ulib.c
 int stat(const char*, struct stat*);

user/usys.pl

@@ -37,3 +37,4 @@ sub entry {
 entry("sleep");
 entry("uptime");
 entry("trace");
+entry("sysinfo");