Merge branch 'master' of g.csail.mit.edu:xv6-dev

1 files changed, 17 insertions, 11 deletions

diff --git a/syscall.c b/syscall.c
index 9ae7536..ee85261 100644
--- a/syscall.c
+++ b/syscall.c
@@ -17,7 +17,9 @@
 int
 fetchint(uint addr, int *ip)
 {
-  if(addr >= proc->sz || addr+4 > proc->sz)
+  struct proc *curproc = myproc();
+
+  if(addr >= curproc->sz || addr+4 > curproc->sz)
     return -1;
   *ip = *(int*)(addr);
   return 0;
@@ -30,14 +32,16 @@ int
 fetchstr(uint addr, char **pp)
 {
   char *s, *ep;
+  struct proc *curproc = myproc();
 
-  if(addr >= proc->sz)
+  if(addr >= curproc->sz)
     return -1;
   *pp = (char*)addr;
-  ep = (char*)proc->sz;
-  for(s = *pp; s < ep; s++)
+  ep = (char*)curproc->sz;
+  for(s = *pp; s < ep; s++){
     if(*s == 0)
       return s - *pp;
+  }
   return -1;
 }
 
@@ -45,7 +49,7 @@ fetchstr(uint addr, char **pp)
 int
 argint(int n, int *ip)
 {
-  return fetchint(proc->tf->esp + 4 + 4*n, ip);
+  return fetchint((myproc()->tf->esp) + 4 + 4*n, ip);
 }
 
 // Fetch the nth word-sized system call argument as a pointer
@@ -55,10 +59,11 @@ int
 argptr(int n, char **pp, int size)
 {
   int i;
-
+  struct proc *curproc = myproc();
+ 
   if(argint(n, &i) < 0)
     return -1;
-  if(size < 0 || (uint)i >= proc->sz || (uint)i+size > proc->sz)
+  if(size < 0 || (uint)i >= curproc->sz || (uint)i+size > curproc->sz)
     return -1;
   *pp = (char*)i;
   return 0;
@@ -127,13 +132,14 @@ void
 syscall(void)
 {
   int num;
+  struct proc *curproc = myproc();
 
-  num = proc->tf->eax;
+  num = curproc->tf->eax;
   if(num > 0 && num < NELEM(syscalls) && syscalls[num]) {
-    proc->tf->eax = syscalls[num]();
+    curproc->tf->eax = syscalls[num]();
   } else {
     cprintf("%d %s: unknown sys call %d\n",
-            proc->pid, proc->name, num);
-    proc->tf->eax = -1;
+            curproc->pid, curproc->name, num);
+    curproc->tf->eax = -1;
   }
 }