diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/ntfs/collate.c |
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/ntfs/collate.c')
-rw-r--r-- | fs/ntfs/collate.c | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/fs/ntfs/collate.c b/fs/ntfs/collate.c new file mode 100644 index 000000000000..4a28ab3898ef --- /dev/null +++ b/fs/ntfs/collate.c @@ -0,0 +1,124 @@ +/* + * collate.c - NTFS kernel collation handling. Part of the Linux-NTFS project. + * + * Copyright (c) 2004 Anton Altaparmakov + * + * This program/include file is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as published + * by the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program/include file is distributed in the hope that it will be + * useful, but WITHOUT ANY WARRANTY; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program (in the main directory of the Linux-NTFS + * distribution in the file COPYING); if not, write to the Free Software + * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include "collate.h" +#include "debug.h" +#include "ntfs.h" + +static int ntfs_collate_binary(ntfs_volume *vol, + const void *data1, const int data1_len, + const void *data2, const int data2_len) +{ + int rc; + + ntfs_debug("Entering."); + rc = memcmp(data1, data2, min(data1_len, data2_len)); + if (!rc && (data1_len != data2_len)) { + if (data1_len < data2_len) + rc = -1; + else + rc = 1; + } + ntfs_debug("Done, returning %i", rc); + return rc; +} + +static int ntfs_collate_ntofs_ulong(ntfs_volume *vol, + const void *data1, const int data1_len, + const void *data2, const int data2_len) +{ + int rc; + u32 d1, d2; + + ntfs_debug("Entering."); + // FIXME: We don't really want to bug here. + BUG_ON(data1_len != data2_len); + BUG_ON(data1_len != 4); + d1 = le32_to_cpup(data1); + d2 = le32_to_cpup(data2); + if (d1 < d2) + rc = -1; + else { + if (d1 == d2) + rc = 0; + else + rc = 1; + } + ntfs_debug("Done, returning %i", rc); + return rc; +} + +typedef int (*ntfs_collate_func_t)(ntfs_volume *, const void *, const int, + const void *, const int); + +static ntfs_collate_func_t ntfs_do_collate0x0[3] = { + ntfs_collate_binary, + NULL/*ntfs_collate_file_name*/, + NULL/*ntfs_collate_unicode_string*/, +}; + +static ntfs_collate_func_t ntfs_do_collate0x1[4] = { + ntfs_collate_ntofs_ulong, + NULL/*ntfs_collate_ntofs_sid*/, + NULL/*ntfs_collate_ntofs_security_hash*/, + NULL/*ntfs_collate_ntofs_ulongs*/, +}; + +/** + * ntfs_collate - collate two data items using a specified collation rule + * @vol: ntfs volume to which the data items belong + * @cr: collation rule to use when comparing the items + * @data1: first data item to collate + * @data1_len: length in bytes of @data1 + * @data2: second data item to collate + * @data2_len: length in bytes of @data2 + * + * Collate the two data items @data1 and @data2 using the collation rule @cr + * and return -1, 0, ir 1 if @data1 is found, respectively, to collate before, + * to match, or to collate after @data2. + * + * For speed we use the collation rule @cr as an index into two tables of + * function pointers to call the appropriate collation function. + */ +int ntfs_collate(ntfs_volume *vol, COLLATION_RULE cr, + const void *data1, const int data1_len, + const void *data2, const int data2_len) { + int i; + + ntfs_debug("Entering."); + /* + * FIXME: At the moment we only support COLLATION_BINARY and + * COLLATION_NTOFS_ULONG, so we BUG() for everything else for now. + */ + BUG_ON(cr != COLLATION_BINARY && cr != COLLATION_NTOFS_ULONG); + i = le32_to_cpu(cr); + BUG_ON(i < 0); + if (i <= 0x02) + return ntfs_do_collate0x0[i](vol, data1, data1_len, + data2, data2_len); + BUG_ON(i < 0x10); + i -= 0x10; + if (likely(i <= 3)) + return ntfs_do_collate0x1[i](vol, data1, data1_len, + data2, data2_len); + BUG(); + return 0; +} |