iincref returns new ref

d80b06a1 · rsc · 35a24c83 · d80b06a1 · d80b06a1 · d80b06a1
--- a/defs.h
+++ b/defs.h
@@ -128,7 +128,7 @@ void ilock(struct inode*);
 void iunlock(struct inode*);
 void itrunc(struct inode*);
 void idecref(struct inode*);
-void iincref(struct inode*);
+struct inode* iincref(struct inode*);
 void iput(struct inode*);
 struct inode* namei(char*, int, uint*, char**, struct inode**);
 void stati(struct inode*, struct stat*);

--- a/fs.c
+++ b/fs.c
@@ -266,8 +266,7 @@ iunlock(struct inode *ip)
 uint
 bmap(struct inode *ip, uint bn)
 {
-  unsigned x;
+  uint *a, x;
-  uint *a;
  struct buf *inbp;
  if(bn >= MAXFILE)
@@ -350,12 +349,14 @@ idecref(struct inode *ip)
 }
 // Increment reference count for ip.
-void
+// Returns ip to enable ip = iincref(ip1) idiom.
+struct inode*
 iincref(struct inode *ip)
 {
  ilock(ip);
  ip->ref++;
  iunlock(ip);
+  return ip;
 }
 // Copy stat information from inode.
@@ -511,8 +512,7 @@ namei(char *path, int mode, uint *ret_off,
  if(*cp == '/')
    dp = iget(rootdev, 1);
  else {
-    dp = p->cwd;
+    dp = iincref(p->cwd);
-    iincref(dp);
    ilock(dp);
  }

--- a/proc.c
+++ b/proc.c
@@ -150,8 +150,7 @@ copyproc(struct proc *p)
      fileincref(np->ofile[i]);
  }
-  np->cwd = p->cwd;
+  np->cwd = iincref(p->cwd);
-  iincref(p->cwd);
  return np;
 }