aboutsummaryrefslogtreecommitdiff
path: root/lib
AgeCommit message (Collapse)Author
2005-10-30[PATCH] lib/string.c cleanup: whitespace and CodingStyle cleanupsJesper Juhl
Removes some blank lines, removes some trailing whitespace, adds spaces after commas and a few similar changes. Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30[PATCH] CONFIG_IA32Brian Gerst
Add CONFIG_X86_32 for i386. This allows selecting options that only apply to 32-bit systems. (X86 && !X86_64) becomes X86_32 (X86 || X86_64) becomes X86 Signed-off-by: Brian Gerst <bgerst@didntduck.org> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-29[PATCH] ppc64 boot: remove include from lib/zlib_inflate/inflate.cOlaf Hering
There is no need to include module.h in inflate.c Signed-off-by: Olaf Hering <olh@suse.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Anton Blanchard <anton@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-28Merge ../bleed-2.6Greg KH
2005-10-28[PATCH] kobject_uevent.c has a typo in a commentErik Hovland
This patch changes trough to through in a comment in kobject_uevent.c. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-10-28[PATCH] gfp_t: lib/*Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-23[PATCH] inotify/idr leak fixAndrew Morton
Fix a bug which was reported and diagnosed by Stefan Jones <stefan.jones@churchillrandoms.co.uk> IDR trees include a cache of idr_layer objects. There's no way to destroy this cache, so when we discard an overall idr tree we end up leaking some memory. Add and use idr_destroy() for this. v9fs and infiniband also need to use idr_destroy() to avoid leaks. Or, we make the cache global, like radix_tree_preload(). Which is probably better. Later. Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org> Cc: Roland Dreier <rolandd@cisco.com> Cc: Robert Love <rml@novell.com> Cc: John McCutchan <ttb@tentacle.dhs.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-20Update from upstream with manual merge of Yasunori Goto'sTony Luck
changes to swiotlb.c made in commit 281dd25cdc0d6903929b79183816d151ea626341 since this file has been moved from arch/ia64/lib/swiotlb.c to lib/swiotlb.c Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-10-18Add some basic .gitignore filesLinus Torvalds
This still leaves driver and architecture-specific subdirectories alone, but gets rid of the bulk of the "generic" generated files that we should ignore. Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-08[PATCH] gfp flags annotations - part 1Al Viro
- added typedef unsigned int __nocast gfp_t; - replaced __nocast uses for gfp flags with gfp_t - it gives exactly the same warnings as far as sparse is concerned, doesn't change generated code (from gcc point of view we replaced unsigned int with typedef) and documents what's going on far better. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-04[TEXTSEARCH]: fix sparse gfp nocast warningsRandy Dunlap
Fix nocast sparse warnings: include/linux/textsearch.h:165:57: warning: implicit cast to nocast type Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-29[PATCH] Removed remaining PCI specific references from swiotlb.cTony Luck
Matthew Wilcox pointed out that swiotlb.c implements a generic interface that is not tied to just PCI. Remove includes of <linux/pci.h>, <asm/pci.h>. Fix comments and printk() messages to no longer refer to PCI. Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-09-29[PATCH] swiotlb: file header commentsJohn W. Linville
Change comment at top of swiotlb.c to reflect that the code is shared with EM64T (i.e. Intel x86_64). Also add an entry for myself so that if I "broke it", everyone knows who "bought it"... :-) Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-09-29[PATCH] swiotlb: support syncing DMA_BIDIRECTIONAL mappingsJohn W. Linville
The current implementation of sync_single in swiotlb.c chokes on DMA_BIDIRECTIONAL mappings. This patch adds the capability to sync those mappings, and optimizes other syncs by accounting for the sync target (i.e. cpu or device) in addition to the DMA direction of the mapping. Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-09-29[PATCH] swiotlb: support syncing sub-ranges of mappingsJohn W. Linville
This patch implements swiotlb_sync_single_range_for_{cpu,device}. This is intended to support an x86_64 implementation of dma_sync_single_range_for_{cpu,device}. Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-09-29[PATCH] swiotlb: cleanup some code duplication cruftJohn W. Linville
The implementations of swiotlb_sync_single_for_{cpu,device} are identical. Likewise for swiotlb_syng_sg_for_{cpu,device}. This patch move the guts of those functions to two new inline functions, and calls the appropriate one from the bodies of those functions. Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-09-29[PATCH] swiotlb: move from arch/ia64/lib/ to lib/John W. Linville
The swiotlb implementation is shared by both IA-64 and EM64T. However, the source itself lives under arch/ia64. This patch moves swiotlb.c from arch/ia64/lib to lib/ and fixes-up the appropriate Makefile and Kconfig files. No actual changes are made to swiotlb.c. Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-09-14[LIB]: Consolidate _atomic_dec_and_lock()David S. Miller
Several implementations were essentialy a common piece of C code using the cmpxchg() macro. Put the implementation in one spot that everyone can share, and convert sparc64 over to using this. Alpha is the lone arch-specific implementation, which codes up a special fast path for the common case in order to avoid GP reloading which a pure C version would require. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-12[PATCH] x86-64: Allow frame pointer and fix help text.Andi Kleen
Allow frame pointer and fix help text. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10[PATCH] lib/sort.c: small cleanupsAdrian Bunk
This patch contains the following small cleanups: - make two needlessly global functions static - every file should #include the header files containing the prototypes of it's global functions Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10[PATCH] lib/radix-tree: Fix "nocast type" warningsVictor Fusco
Fix the sparse warning "implicit cast to nocast type" Signed-off-by: Victor Fusco <victor@cetuc.puc-rio.br> Signed-off-by: Domen Puncer <domen@coderock.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10[PATCH] spinlock consolidationIngo Molnar
This patch (written by me and also containing many suggestions of Arjan van de Ven) does a major cleanup of the spinlock code. It does the following things: - consolidates and enhances the spinlock/rwlock debugging code - simplifies the asm/spinlock.h files - encapsulates the raw spinlock type and moves generic spinlock features (such as ->break_lock) into the generic code. - cleans up the spinlock code hierarchy to get rid of the spaghetti. Most notably there's now only a single variant of the debugging code, located in lib/spinlock_debug.c. (previously we had one SMP debugging variant per architecture, plus a separate generic one for UP builds) Also, i've enhanced the rwlock debugging facility, it will now track write-owners. There is new spinlock-owner/CPU-tracking on SMP builds too. All locks have lockup detection now, which will work for both soft and hard spin/rwlock lockups. The arch-level include files now only contain the minimally necessary subset of the spinlock code - all the rest that can be generalized now lives in the generic headers: include/asm-i386/spinlock_types.h | 16 include/asm-x86_64/spinlock_types.h | 16 I have also split up the various spinlock variants into separate files, making it easier to see which does what. The new layout is: SMP | UP ----------------------------|----------------------------------- asm/spinlock_types_smp.h | linux/spinlock_types_up.h linux/spinlock_types.h | linux/spinlock_types.h asm/spinlock_smp.h | linux/spinlock_up.h linux/spinlock_api_smp.h | linux/spinlock_api_up.h linux/spinlock.h | linux/spinlock.h /* * here's the role of the various spinlock/rwlock related include files: * * on SMP builds: * * asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the * initializers * * linux/spinlock_types.h: * defines the generic type and initializers * * asm/spinlock.h: contains the __raw_spin_*()/etc. lowlevel * implementations, mostly inline assembly code * * (also included on UP-debug builds:) * * linux/spinlock_api_smp.h: * contains the prototypes for the _spin_*() APIs. * * linux/spinlock.h: builds the final spin_*() APIs. * * on UP builds: * * linux/spinlock_type_up.h: * contains the generic, simplified UP spinlock type. * (which is an empty structure on non-debug builds) * * linux/spinlock_types.h: * defines the generic type and initializers * * linux/spinlock_up.h: * contains the __raw_spin_*()/etc. version of UP * builds. (which are NOPs on non-debug, non-preempt * builds) * * (included on UP-non-debug builds:) * * linux/spinlock_api_up.h: * builds the _spin_*() APIs. * * linux/spinlock.h: builds the final spin_*() APIs. */ All SMP and UP architectures are converted by this patch. arm, i386, ia64, ppc, ppc64, s390/s390x, x64 was build-tested via crosscompilers. m32r, mips, sh, sparc, have not been tested yet, but should be mostly fine. From: Grant Grundler <grundler@parisc-linux.org> Booted and lightly tested on a500-44 (64-bit, SMP kernel, dual CPU). Builds 32-bit SMP kernel (not booted or tested). I did not try to build non-SMP kernels. That should be trivial to fix up later if necessary. I converted bit ops atomic_hash lock to raw_spinlock_t. Doing so avoids some ugly nesting of linux/*.h and asm/*.h files. Those particular locks are well tested and contained entirely inside arch specific code. I do NOT expect any new issues to arise with them. If someone does ever need to use debug/metrics with them, then they will need to unravel this hairball between spinlocks, atomic ops, and bit ops that exist only because parisc has exactly one atomic instruction: LDCW (load and clear word). From: "Luck, Tony" <tony.luck@intel.com> ia64 fix Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjanv@infradead.org> Signed-off-by: Grant Grundler <grundler@parisc-linux.org> Cc: Matthew Wilcox <willy@debian.org> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Mikael Pettersson <mikpe@csd.uu.se> Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-08[PATCH] lib/crc16: added crc16 algorithm.Evgeniy Polyakov
Add the crc16 routines, as used by w1 devices. Signed-off-by: Ben Gardner <bgardner@wabtec.com> Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-07[PATCH] fix klist semantics for lists which have elements removed on traversalJames Bottomley
The problem is that klists claim to provide semantics for safe traversal of lists which are being modified. The failure case is when traversal of a list causes element removal (a fairly common case). The issue is that although the list node is refcounted, if it is embedded in an object (which is universally the case), then the object will be freed regardless of the klist refcount leading to slab corruption because the klist iterator refers to the prior element to get the next. The solution is to make the klist take and release references to the embedding object meaning that the embedding object won't be released until the list relinquishes the reference to it. (akpm: fast-track this because it's needed for the 2.6.13 scsi merge) Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07[PATCH] radix_tag_get(): differentiate between no present node and tag unset ↵Marcelo Tosatti
cases Simple patch to radix_tree_tag_get() to return different values for non present node and tag unset. The function is not used by any in-kernel callers (yet), but this information is definitely useful. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07[PATCH] radix-tree: Remove unnecessary indirections and clean up codeChristoph Lameter
- There is frequent use of indirections in the radix code. This patch removes those indirections, makes the code more readable and allows the compilers to generate better code. - Removing indirections allows the removal of several casts. - Removing indirections allows the reduction of the radix_tree_path size from 3 to 2 words. - Use pathp-> consistently. - Remove unnecessary tmp variable in radix_tree_insert - Separate the upper layer processing from the lowest layer in __lookup() in order to make it easier to understand what is going on and allow compilers to generate better code for the loop. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: James Bottomley <James.Bottomley@steeleye.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07[PATCH] detect soft lockupsIngo Molnar
This patch adds a new kernel debug feature: CONFIG_DETECT_SOFTLOCKUP. When enabled then per-CPU watchdog threads are started, which try to run once per second. If they get delayed for more than 10 seconds then a callback from the timer interrupt detects this condition and prints out a warning message and a stack dump (once per lockup incident). The feature is otherwise non-intrusive, it doesnt try to unlock the box in any way, it only gets the debug info out, automatically, and on all CPUs affected by the lockup. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com> Signed-Off-By: Matthias Urlichs <smurf@smurf.noris.de> Signed-off-by: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05[PATCH] klist: fix klist to have the same klist_add semantics as list_headJames Bottomley
at the moment, the list_head semantics are list_add(node, head) whereas current klist semantics are klist_add(head, node) This is bound to cause confusion, and since klist is the newcomer, it should follow the list_head semantics. I also added missing include guards to klist.h Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05[PATCH] unify x86/x86-64 semaphore codeBenjamin LaHaise
This patch moves the common code in x86 and x86-64's semaphore.c into a single file in lib/semaphore-sleepers.c. The arch specific asm stubs are left in the arch tree (in semaphore.c for i386 and in the asm for x86-64). There should be no changes in code/functionality with this patch. Signed-off-by: Benjamin LaHaise <benjamin.c.lahaise@intel.com> Cc: Andi Kleen <ak@muc.de> Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-29[LIB]: Make TEXTSEARCH_BM plain tristate like the othersDavid S. Miller
And select it when the relevant modules are enabled. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[LIB]: Boyer-Moore extension for textsearch infrastructure strike #2Pablo Neira Ayuso
Attached the implementation of the Boyer-Moore string search algorithm for the new textsearch infrastructure. I've added as well a note about the limitations that this approach presents, as Thomas has remarked. Signed-off-by: Pablo Neira Ayuso <pablo@eurodev.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETLINK]: Add "groups" argument to netlink_kernel_createPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETLINK]: Convert netlink users to use group numbers instead of bitmasksPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETLINK]: Fix missing dst_groups initializations in netlink_broadcast usersPatrick McHardy
netlink_broadcast users must initialize NETLINK_CB(skb).dst_groups to the destination group mask for netlink_recvmsg. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NETLINK]: Add properly module refcounting for kernel netlink sockets.Harald Welte
- Remove bogus code for compiling netlink as module - Add module refcounting support for modules implementing a netlink protocol - Add support for autoloading modules that implement a netlink protocol as soon as someone opens a socket for that protocol Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-26[PATCH] Document idr_get_new_above() semantics, update inotifyJohn McCutchan
There is an off by one problem with idr_get_new_above. The comment and function name suggest that it will return an id > starting_id, but it actually returned an id >= starting_id, and kernel callers other than inotify treated it as such. The patch below fixes the comment, and fixes inotifys usage. The function name still doesn't match the behaviour, but it never did. Signed-off-by: John McCutchan <ttb@tentacle.dhs.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-23[PATCH] %t... in vsnprintfAl Viro
handling of %t... (ptrdiff_t) in vsnprintf Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-17Revert unnecessary zlib_inflate/inftrees.c fixLinus Torvalds
It turns out that empty distance code tables are not an error, and that a compressed block with only literals can validly have an empty table and should not be flagged as a data error. Some old versions of gzip had problems with this case, but it does not affect the zlib code in the kernel. Analysis and explanations thanks to Sergey Vlasov <vsu@altlinux.ru> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-07[PATCH] crc32.c typo fixDominik Hackl
This patch fixes a typo in lib/crc32.c which results in incorrect debug output. Signed-off-by: Dominik Hackl <dominik@hackl.dhs.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-05[PATCH] Update in-kernel zlib routinesTim Yamin
These bugs have been fixed in the standard zlib for a while. See for example a) http://sources.redhat.com/ml/bug-gnu-utils/1999-06/msg00183.html b) http://bugs.gentoo.org/show_bug.cgi?id=94584 Signed-off-by: Tim Yamin <plasmaroo@gentoo.org> Signed-off-by: Tavis Ormandy <taviso@gentoo.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-29[PATCH] DEBUG_FS must depend on SYSFSAdrian Bunk
CONFIG_DEBUG_FS=y and CONFIG_SYSFS=n results in the following compile error: <-- snip --> ... LD vmlinux fs/built-in.o: In function `debugfs_init': inode.c:(.init.text+0x31be): undefined reference to `kernel_subsys' make: *** [vmlinux] Error 1 <-- snip --> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27[PATCH] statically link halfmd4Andrew Morton
For some reason halfmd4 isn't being linked into the kernel any more and modular ext3 wants it. So statically link the halfmd4 code into the kernel. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-07[PATCH] mostly_read data sectionChristoph Lameter
Add a new section called ".data.read_mostly" for data items that are read frequently and rarely written to like cpumaps etc. If these maps are placed in the .data section then these frequenly read items may end up in cachelines with data is is frequently updated. In that case all processors in an SMP system must needlessly reload the cachelines again and again containing elements of those frequently used variables. The ability to share these cachelines will allow each cpu in an SMP system to keep local copies of those shared cachelines thereby optimizing performance. Signed-off-by: Alok N Kataria <alokk@calsoftinc.com> Signed-off-by: Shobhit Dayal <shobhit@calsoftinc.com> Signed-off-by: Christoph Lameter <christoph@scalex86.org> Signed-off-by: Shai Fultheim <shai@scalex86.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] Use ALIGN to remove duplicate codeNick Wilson
This patch makes use of ALIGN() to remove duplicate round-up code. Signed-off-by: Nick Wilson <njw@osdl.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] lib/sha1.c: fix sparse warningDomen Puncer
lib/sha1.c:44:10: warning: cast to restricted type Signed-off-by: Alexey Dobriyan <adobriyan@mail.ru> Signed-off-by: Domen Puncer <domen@coderock.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-24[PKT_SCHED]: Make TEXTSEARCH* options only selected.David S. Miller
Do not present these confusing new options to the user unless he picked some facility that makes use of it, such as NET_EMATCH_TEXT. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23[LIB]: textsearch.o needs to be obj-y not lib-y.David S. Miller
It exports symbols. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23[LIB]: Naive finite state machine based textsearchThomas Graf
A finite state machine consists of n states (struct ts_fsm_token) representing the pattern as a finite automation. The data is read sequentially on a octet basis. Every state token specifies the number of recurrences and the type of value accepted which can be either a specific character or ctype based set of characters. The available type of recurrences include 1, (0|1), [0 n], and [1 n]. The algorithm differs between strict/non-strict mode specyfing whether the pattern has to start at the first octect. Strict mode is enabled by default and can be disabled by inserting TS_FSM_HEAD_IGNORE as the first token in the chain. The runtime performance of the algorithm should be around O(n), however while in strict mode the average runtime can be better. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23[LIB]: Knuth-Morris-Pratt textsearch algorithmThomas Graf
Implements a linear-time string-matching algorithm due to Knuth, Morris, and Pratt [1]. Their algorithm avoids the explicit computation of the transition function DELTA altogether. Its matching time is O(n), for n being length(text), using just an auxiliary function PI[1..m], for m being length(pattern), precomputed from the pattern in time O(m). The array PI allows the transition function DELTA to be computed efficiently "on the fly" as needed. Roughly speaking, for any state "q" = 0,1,...,m and any character "a" in SIGMA, the value PI["q"] contains the information that is independent of "a" and is needed to compute DELTA("q", "a") [2]. Since the array PI has only m entries, whereas DELTA has O(m|SIGMA|) entries, we save a factor of |SIGMA| in the preprocessing time by computing PI rather than DELTA. [1] Cormen, Leiserson, Rivest, Stein Introdcution to Algorithms, 2nd Edition, MIT Press [2] See finite automation theory Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23[LIB]: Textsearch infrastructure.Thomas Graf
The textsearch infrastructure provides text searching facitilies for both linear and non-linear data. Individual search algorithms are implemented in modules and chosen by the user. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>