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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 02:20:36 +0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 02:20:36 +0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/cramfs/uncompress.c | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz |
Linux-2.6.12-rc2v2.6.12-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/cramfs/uncompress.c')
-rw-r--r-- | fs/cramfs/uncompress.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/fs/cramfs/uncompress.c b/fs/cramfs/uncompress.c new file mode 100644 index 000000000000..5034365b06a8 --- /dev/null +++ b/fs/cramfs/uncompress.c @@ -0,0 +1,77 @@ +/* + * uncompress.c + * + * (C) Copyright 1999 Linus Torvalds + * + * cramfs interfaces to the uncompression library. There's really just + * three entrypoints: + * + * - cramfs_uncompress_init() - called to initialize the thing. + * - cramfs_uncompress_exit() - tell me when you're done + * - cramfs_uncompress_block() - uncompress a block. + * + * NOTE NOTE NOTE! The uncompression is entirely single-threaded. We + * only have one stream, and we'll initialize it only once even if it + * then is used by multiple filesystems. + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/vmalloc.h> +#include <linux/zlib.h> + +static z_stream stream; +static int initialized; + +/* Returns length of decompressed data. */ +int cramfs_uncompress_block(void *dst, int dstlen, void *src, int srclen) +{ + int err; + + stream.next_in = src; + stream.avail_in = srclen; + + stream.next_out = dst; + stream.avail_out = dstlen; + + err = zlib_inflateReset(&stream); + if (err != Z_OK) { + printk("zlib_inflateReset error %d\n", err); + zlib_inflateEnd(&stream); + zlib_inflateInit(&stream); + } + + err = zlib_inflate(&stream, Z_FINISH); + if (err != Z_STREAM_END) + goto err; + return stream.total_out; + +err: + printk("Error %d while decompressing!\n", err); + printk("%p(%d)->%p(%d)\n", src, srclen, dst, dstlen); + return 0; +} + +int cramfs_uncompress_init(void) +{ + if (!initialized++) { + stream.workspace = vmalloc(zlib_inflate_workspacesize()); + if ( !stream.workspace ) { + initialized = 0; + return -ENOMEM; + } + stream.next_in = NULL; + stream.avail_in = 0; + zlib_inflateInit(&stream); + } + return 0; +} + +int cramfs_uncompress_exit(void) +{ + if (!--initialized) { + zlib_inflateEnd(&stream); + vfree(stream.workspace); + } + return 0; +} |