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authorrsc <rsc>2007-08-27 14:31:50 +0000
committerrsc <rsc>2007-08-27 14:31:50 +0000
commit7895178df374a1a89c193e5c83a37a35243aadc2 (patch)
tree9d8600efed523dfd6dc696aab3d62bc92cc0520a
parent6c34f97cb889456c2340a3935d1253f99ec13522 (diff)
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nits
-rw-r--r--fs.c52
1 files changed, 23 insertions, 29 deletions
diff --git a/fs.c b/fs.c
index a6c4732..fb82f91 100644
--- a/fs.c
+++ b/fs.c
@@ -143,7 +143,7 @@ iinit(void)
}
// Find the inode with number inum on device dev
-// and return the in-memory copy. h
+// and return the in-memory copy.
static struct inode*
iget(uint dev, uint inum)
{
@@ -255,6 +255,7 @@ iput(struct inode *ip)
release(&icache.lock);
}
+// Common idiom: unlock, then put.
void
iunlockput(struct inode *ip)
{
@@ -275,7 +276,7 @@ ialloc(uint dev, short type)
readsb(dev, &sb);
for(inum = 1; inum < sb.ninodes; inum++) { // loop over inode blocks
bp = bread(dev, IBLOCK(inum));
- dip = &((struct dinode*)(bp->data))[inum % IPB];
+ dip = (struct dinode*)(bp->data) + inum%IPB;
if(dip->type == 0) { // a free inode
memset(dip, 0, sizeof(*dip));
dip->type = type;
@@ -296,7 +297,7 @@ iupdate(struct inode *ip)
struct dinode *dip;
bp = bread(ip->dev, IBLOCK(ip->inum));
- dip = &((struct dinode*)(bp->data))[ip->inum % IPB];
+ dip = (struct dinode*)(bp->data) + ip->inum%IPB;
dip->type = ip->type;
dip->major = ip->major;
dip->minor = ip->minor;
@@ -312,7 +313,7 @@ iupdate(struct inode *ip)
//
// The contents (data) associated with each inode is stored
// in a sequence of blocks on the disk. The first NDIRECT blocks
-// are stored in ip->addrs[]. The next NINDIRECT blocks are
+// are listed in ip->addrs[]. The next NINDIRECT blocks are
// listed in the block ip->addrs[INDIRECT].
// Return the disk block address of the nth block in inode ip.
@@ -414,7 +415,7 @@ readi(struct inode *ip, char *dst, uint off, uint n)
return devsw[ip->major].read(ip->minor, dst, n);
}
- if(off + n < off)
+ if(off > ip->size || off + n < off)
return -1;
if(off + n > ip->size)
n = ip->size - off;
@@ -486,8 +487,8 @@ dirlookup(struct inode *dp, char *name, uint *poff)
for(off = 0; off < dp->size; off += BSIZE){
bp = bread(dp->dev, bmap(dp, off / BSIZE, 0));
- for(de = (struct dirent*) bp->data;
- de < (struct dirent*) (bp->data + BSIZE);
+ for(de = (struct dirent*)bp->data;
+ de < (struct dirent*)(bp->data + BSIZE);
de++){
if(de->inum == 0)
continue;
@@ -522,7 +523,7 @@ dirlink(struct inode *dp, char *name, uint ino)
// Look for an empty dirent.
for(off = 0; off < dp->size; off += sizeof(de)){
if(readi(dp, (char*)&de, off, sizeof(de)) != sizeof(de))
- panic("dirwrite read");
+ panic("dirlink read");
if(de.inum == 0)
break;
}
@@ -530,7 +531,7 @@ dirlink(struct inode *dp, char *name, uint ino)
strncpy(de.name, name, DIRSIZ);
de.inum = ino;
if(writei(dp, (char*)&de, off, sizeof(de)) != sizeof(de))
- panic("dirwrite");
+ panic("dirlink");
return 0;
}
@@ -546,7 +547,7 @@ dirlink(struct inode *dp, char *name, uint ino)
//
// Examples:
// skipelem("a/bb/c", name) = "bb/c", setting name = "a"
-// skipelem("///a/bb", name) = "bb", setting name="a"
+// skipelem("///a//bb", name) = "bb", setting name = "a"
// skipelem("", name) = skipelem("////", name) = 0
//
static char*
@@ -574,21 +575,6 @@ skipelem(char *path, char *name)
return path;
}
-static struct inode* _namei(char*, int, char*);
-
-struct inode*
-namei(char *path)
-{
- char name[DIRSIZ];
- return _namei(path, 0, name);
-}
-
-struct inode*
-nameiparent(char *path, char *name)
-{
- return _namei(path, 1, name);
-}
-
// Look up and return the inode for a path name.
// If parent is set, return the inode for the parent
// and write the final path element to name, which
@@ -597,7 +583,6 @@ static struct inode*
_namei(char *path, int parent, char *name)
{
struct inode *ip, *next;
- uint off;
if(*path == '/')
ip = iget(ROOTDEV, 1);
@@ -610,14 +595,12 @@ _namei(char *path, int parent, char *name)
iunlockput(ip);
return 0;
}
-
if(parent && *path == '\0'){
// Stop one level early.
iunlock(ip);
return ip;
}
-
- if((next = dirlookup(ip, name, &off)) == 0){
+ if((next = dirlookup(ip, name, 0)) == 0){
iunlockput(ip);
return 0;
}
@@ -631,3 +614,14 @@ _namei(char *path, int parent, char *name)
return ip;
}
+struct inode*
+namei(char *path)
+{
+ char name[DIRSIZ];
+ return _namei(path, 0, name);
+}
+struct inode*
+nameiparent(char *path, char *name)
+{
+ return _namei(path, 1, name);
+}