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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/jffs2/pushpull.h | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/jffs2/pushpull.h')
-rw-r--r-- | fs/jffs2/pushpull.h | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/fs/jffs2/pushpull.h b/fs/jffs2/pushpull.h new file mode 100644 index 0000000..c0c2a91 --- /dev/null +++ b/fs/jffs2/pushpull.h @@ -0,0 +1,72 @@ +/* + * JFFS2 -- Journalling Flash File System, Version 2. + * + * Copyright (C) 2001, 2002 Red Hat, Inc. + * + * Created by David Woodhouse <dwmw2@infradead.org> + * + * For licensing information, see the file 'LICENCE' in this directory. + * + * $Id: pushpull.h,v 1.10 2004/11/16 20:36:11 dwmw2 Exp $ + * + */ + +#ifndef __PUSHPULL_H__ +#define __PUSHPULL_H__ + +#include <linux/errno.h> + +struct pushpull { + unsigned char *buf; + unsigned int buflen; + unsigned int ofs; + unsigned int reserve; +}; + + +static inline void init_pushpull(struct pushpull *pp, char *buf, unsigned buflen, unsigned ofs, unsigned reserve) +{ + pp->buf = buf; + pp->buflen = buflen; + pp->ofs = ofs; + pp->reserve = reserve; +} + +static inline int pushbit(struct pushpull *pp, int bit, int use_reserved) +{ + if (pp->ofs >= pp->buflen - (use_reserved?0:pp->reserve)) { + return -ENOSPC; + } + + if (bit) { + pp->buf[pp->ofs >> 3] |= (1<<(7-(pp->ofs &7))); + } + else { + pp->buf[pp->ofs >> 3] &= ~(1<<(7-(pp->ofs &7))); + } + pp->ofs++; + + return 0; +} + +static inline int pushedbits(struct pushpull *pp) +{ + return pp->ofs; +} + +static inline int pullbit(struct pushpull *pp) +{ + int bit; + + bit = (pp->buf[pp->ofs >> 3] >> (7-(pp->ofs & 7))) & 1; + + pp->ofs++; + return bit; +} + +static inline int pulledbits(struct pushpull *pp) +{ + return pp->ofs; +} + +#endif /* __PUSHPULL_H__ */ |