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formatting, cleanup

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rsc 2007-08-14 19:41:56 +00:00
parent cce27ba9fb
commit 2186f88c21
1 changed files with 55 additions and 57 deletions
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110
file.c
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@ -41,75 +41,55 @@ filealloc(void)
return 0;
}
// Write to file f. Addr is kernel address.
int
filewrite(struct file *f, char *addr, int n)
// Increment ref count for file f.
void
fileincref(struct file *f)
{
if(f->writable == 0)
return -1;
if(f->type == FD_PIPE){
return pipe_write(f->pipe, addr, n);
} else if(f->type == FD_FILE) {
ilock(f->ip);
int r = writei(f->ip, addr, f->off, n);
if(r > 0) {
f->off += r;
}
iunlock(f->ip);
return r;
} else {
panic("filewrite");
return -1;
}
acquire(&file_table_lock);
if(f->ref < 1 || f->type == FD_CLOSED)
panic("fileincref");
f->ref++;
release(&file_table_lock);
}
// Read from file f. Addr is kernel address.
int
fileread(struct file *f, char *addr, int n)
{
int r;
if(f->readable == 0)
return -1;
if(f->type == FD_PIPE){
if(f->type == FD_PIPE)
return pipe_read(f->pipe, addr, n);
} else if(f->type == FD_FILE){
if(f->type == FD_FILE){
ilock(f->ip);
int cc = readi(f->ip, addr, f->off, n);
if(cc > 0)
f->off += cc;
if((r = readi(f->ip, addr, f->off, n)) > 0)
f->off += r;
iunlock(f->ip);
return cc;
} else {
return r;
}
panic("fileread");
return -1;
}
}
// Close file f. (Decrement ref count, close when reaches 0.)
void
fileclose(struct file *f)
// Write to file f. Addr is kernel address.
int
filewrite(struct file *f, char *addr, int n)
{
acquire(&file_table_lock);
int r;
if(f->ref < 1 || f->type == FD_CLOSED)
panic("fileclose");
if(--f->ref == 0){
struct file dummy = *f;
f->ref = 0;
f->type = FD_CLOSED;
release(&file_table_lock);
if(dummy.type == FD_PIPE){
pipe_close(dummy.pipe, dummy.writable);
} else if(dummy.type == FD_FILE){
idecref(dummy.ip);
} else {
panic("fileclose");
}
} else {
release(&file_table_lock);
if(f->writable == 0)
return -1;
if(f->type == FD_PIPE)
return pipe_write(f->pipe, addr, n);
if(f->type == FD_FILE){
ilock(f->ip);
if((r = writei(f->ip, addr, f->off, n)) > 0)
f->off += r;
iunlock(f->ip);
return r;
}
panic("filewrite");
}
// Get metadata about file f.
@ -121,17 +101,35 @@ filestat(struct file *f, struct stat *st)
stati(f->ip, st);
iunlock(f->ip);
return 0;
} else
}
return -1;
}
// Increment ref count for file f.
// Close file f. (Decrement ref count, close when reaches 0.)
void
fileincref(struct file *f)
fileclose(struct file *f)
{
struct file ff;
acquire(&file_table_lock);
if(f->ref < 1 || f->type == FD_CLOSED)
panic("fileincref");
f->ref++;
panic("fileclose");
if(--f->ref > 0){
release(&file_table_lock);
return;
}
ff = *f;
f->ref = 0;
f->type = FD_CLOSED;
release(&file_table_lock);
if(ff.type == FD_PIPE)
pipe_close(ff.pipe, ff.writable);
else if(ff.type == FD_FILE)
idecref(ff.ip);
else
panic("fileclose");
}