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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-06-24 00:31:46 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-06-24 00:31:46 -0700
commit59a49e38711a146dc0bef4837c825b5422335460 (patch)
tree7e6e3d1850159f94e5b05d1c5775bd3cc87c3690 /lib
parent52c1da39534fb382c061de58b65f678ad74b59f5 (diff)
parentf2d368fa3ef90f2159d9e542303901ebf68144dd (diff)
Merge rsync://rsync.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
Diffstat (limited to 'lib')
-rw-r--r--lib/Kconfig29
-rw-r--r--lib/Makefile4
-rw-r--r--lib/textsearch.c317
-rw-r--r--lib/ts_fsm.c338
-rw-r--r--lib/ts_kmp.c145
5 files changed, 832 insertions, 1 deletions
diff --git a/lib/Kconfig b/lib/Kconfig
index 2d4d4e3bc4a..455833a9e31 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -63,5 +63,32 @@ config REED_SOLOMON_ENC16
config REED_SOLOMON_DEC16
boolean
-endmenu
+config TEXTSEARCH
+ boolean "Textsearch infrastructure"
+ default y
+ help
+ Say Y here if you want to provide a textsearch infrastructure
+ to other subsystems.
+
+config TEXTSEARCH_KMP
+ depends on TEXTSEARCH
+ tristate "Knuth-Morris-Pratt"
+ help
+ Say Y here if you want to be able to search text using the
+ Knuth-Morris-Pratt textsearch algorithm.
+ To compile this code as a module, choose M here: the
+ module will be called ts_kmp.
+
+config TEXTSEARCH_FSM
+ depends on TEXTSEARCH
+ tristate "Finite state machine"
+ help
+ Say Y here if you want to be able to search text using a
+ naive finite state machine approach implementing a subset
+ of regular expressions.
+
+ To compile this code as a module, choose M here: the
+ module will be called ts_fsm.
+
+endmenu
diff --git a/lib/Makefile b/lib/Makefile
index dcb4231916e..beed1585294 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -36,6 +36,10 @@ obj-$(CONFIG_ZLIB_INFLATE) += zlib_inflate/
obj-$(CONFIG_ZLIB_DEFLATE) += zlib_deflate/
obj-$(CONFIG_REED_SOLOMON) += reed_solomon/
+obj-$(CONFIG_TEXTSEARCH) += textsearch.o
+obj-$(CONFIG_TEXTSEARCH_KMP) += ts_kmp.o
+obj-$(CONFIG_TEXTSEARCH_FSM) += ts_fsm.o
+
hostprogs-y := gen_crc32table
clean-files := crc32table.h
diff --git a/lib/textsearch.c b/lib/textsearch.c
new file mode 100644
index 00000000000..1e934c196f0
--- /dev/null
+++ b/lib/textsearch.c
@@ -0,0 +1,317 @@
+/*
+ * lib/textsearch.c Generic text search interface
+ *
+ * This program 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.
+ *
+ * Authors: Thomas Graf <tgraf@suug.ch>
+ * Pablo Neira Ayuso <pablo@eurodev.net>
+ *
+ * ==========================================================================
+ *
+ * INTRODUCTION
+ *
+ * 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.
+ *
+ * ARCHITECTURE
+ *
+ * User
+ * +----------------+
+ * | finish()|<--------------(6)-----------------+
+ * |get_next_block()|<--------------(5)---------------+ |
+ * | | Algorithm | |
+ * | | +------------------------------+
+ * | | | init() find() destroy() |
+ * | | +------------------------------+
+ * | | Core API ^ ^ ^
+ * | | +---------------+ (2) (4) (8)
+ * | (1)|----->| prepare() |---+ | |
+ * | (3)|----->| find()/next() |-----------+ |
+ * | (7)|----->| destroy() |----------------------+
+ * +----------------+ +---------------+
+ *
+ * (1) User configures a search by calling _prepare() specifying the
+ * search parameters such as the pattern and algorithm name.
+ * (2) Core requests the algorithm to allocate and initialize a search
+ * configuration according to the specified parameters.
+ * (3) User starts the search(es) by calling _find() or _next() to
+ * fetch subsequent occurrences. A state variable is provided
+ * to the algorihtm to store persistant variables.
+ * (4) Core eventually resets the search offset and forwards the find()
+ * request to the algorithm.
+ * (5) Algorithm calls get_next_block() provided by the user continously
+ * to fetch the data to be searched in block by block.
+ * (6) Algorithm invokes finish() after the last call to get_next_block
+ * to clean up any leftovers from get_next_block. (Optional)
+ * (7) User destroys the configuration by calling _destroy().
+ * (8) Core notifies the algorithm to destroy algorithm specific
+ * allocations. (Optional)
+ *
+ * USAGE
+ *
+ * Before a search can be performed, a configuration must be created
+ * by calling textsearch_prepare() specyfing the searching algorithm and
+ * the pattern to look for. The returned configuration may then be used
+ * for an arbitary amount of times and even in parallel as long as a
+ * separate struct ts_state variable is provided to every instance.
+ *
+ * The actual search is performed by either calling textsearch_find_-
+ * continuous() for linear data or by providing an own get_next_block()
+ * implementation and calling textsearch_find(). Both functions return
+ * the position of the first occurrence of the patern or UINT_MAX if
+ * no match was found. Subsequent occurences can be found by calling
+ * textsearch_next() regardless of the linearity of the data.
+ *
+ * Once you're done using a configuration it must be given back via
+ * textsearch_destroy.
+ *
+ * EXAMPLE
+ *
+ * int pos;
+ * struct ts_config *conf;
+ * struct ts_state state;
+ * const char *pattern = "chicken";
+ * const char *example = "We dance the funky chicken";
+ *
+ * conf = textsearch_prepare("kmp", pattern, strlen(pattern),
+ * GFP_KERNEL, TS_AUTOLOAD);
+ * if (IS_ERR(conf)) {
+ * err = PTR_ERR(conf);
+ * goto errout;
+ * }
+ *
+ * pos = textsearch_find_continuous(conf, &state, example, strlen(example));
+ * if (pos != UINT_MAX)
+ * panic("Oh my god, dancing chickens at %d\n", pos);
+ *
+ * textsearch_destroy(conf);
+ *
+ * ==========================================================================
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/rcupdate.h>
+#include <linux/err.h>
+#include <linux/textsearch.h>
+
+static LIST_HEAD(ts_ops);
+static DEFINE_SPINLOCK(ts_mod_lock);
+
+static inline struct ts_ops *lookup_ts_algo(const char *name)
+{
+ struct ts_ops *o;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(o, &ts_ops, list) {
+ if (!strcmp(name, o->name)) {
+ if (!try_module_get(o->owner))
+ o = NULL;
+ rcu_read_unlock();
+ return o;
+ }
+ }
+ rcu_read_unlock();
+
+ return NULL;
+}
+
+/**
+ * textsearch_register - register a textsearch module
+ * @ops: operations lookup table
+ *
+ * This function must be called by textsearch modules to announce
+ * their presence. The specified &@ops must have %name set to a
+ * unique identifier and the callbacks find(), init(), get_pattern(),
+ * and get_pattern_len() must be implemented.
+ *
+ * Returns 0 or -EEXISTS if another module has already registered
+ * with same name.
+ */
+int textsearch_register(struct ts_ops *ops)
+{
+ int err = -EEXIST;
+ struct ts_ops *o;
+
+ if (ops->name == NULL || ops->find == NULL || ops->init == NULL ||
+ ops->get_pattern == NULL || ops->get_pattern_len == NULL)
+ return -EINVAL;
+
+ spin_lock(&ts_mod_lock);
+ list_for_each_entry(o, &ts_ops, list) {
+ if (!strcmp(ops->name, o->name))
+ goto errout;
+ }
+
+ list_add_tail_rcu(&ops->list, &ts_ops);
+ err = 0;
+errout:
+ spin_unlock(&ts_mod_lock);
+ return err;
+}
+
+/**
+ * textsearch_unregister - unregister a textsearch module
+ * @ops: operations lookup table
+ *
+ * This function must be called by textsearch modules to announce
+ * their disappearance for examples when the module gets unloaded.
+ * The &ops parameter must be the same as the one during the
+ * registration.
+ *
+ * Returns 0 on success or -ENOENT if no matching textsearch
+ * registration was found.
+ */
+int textsearch_unregister(struct ts_ops *ops)
+{
+ int err = 0;
+ struct ts_ops *o;
+
+ spin_lock(&ts_mod_lock);
+ list_for_each_entry(o, &ts_ops, list) {
+ if (o == ops) {
+ list_del_rcu(&o->list);
+ goto out;
+ }
+ }
+
+ err = -ENOENT;
+out:
+ spin_unlock(&ts_mod_lock);
+ return err;
+}
+
+struct ts_linear_state
+{
+ unsigned int len;
+ const void *data;
+};
+
+static unsigned int get_linear_data(unsigned int consumed, const u8 **dst,
+ struct ts_config *conf,
+ struct ts_state *state)
+{
+ struct ts_linear_state *st = (struct ts_linear_state *) state->cb;
+
+ if (likely(consumed < st->len)) {
+ *dst = st->data + consumed;
+ return st->len - consumed;
+ }
+
+ return 0;
+}
+
+/**
+ * textsearch_find_continuous - search a pattern in continuous/linear data
+ * @conf: search configuration
+ * @state: search state
+ * @data: data to search in
+ * @len: length of data
+ *
+ * A simplified version of textsearch_find() for continuous/linear data.
+ * Call textsearch_next() to retrieve subsequent matches.
+ *
+ * Returns the position of first occurrence of the pattern or
+ * UINT_MAX if no occurrence was found.
+ */
+unsigned int textsearch_find_continuous(struct ts_config *conf,
+ struct ts_state *state,
+ const void *data, unsigned int len)
+{
+ struct ts_linear_state *st = (struct ts_linear_state *) state->cb;
+
+ conf->get_next_block = get_linear_data;
+ st->data = data;
+ st->len = len;
+
+ return textsearch_find(conf, state);
+}
+
+/**
+ * textsearch_prepare - Prepare a search
+ * @algo: name of search algorithm
+ * @pattern: pattern data
+ * @len: length of pattern
+ * @gfp_mask: allocation mask
+ * @flags: search flags
+ *
+ * Looks up the search algorithm module and creates a new textsearch
+ * configuration for the specified pattern. Upon completion all
+ * necessary refcnts are held and the configuration must be put back
+ * using textsearch_put() after usage.
+ *
+ * Note: The format of the pattern may not be compatible between
+ * the various search algorithms.
+ *
+ * Returns a new textsearch configuration according to the specified
+ * parameters or a ERR_PTR().
+ */
+struct ts_config *textsearch_prepare(const char *algo, const void *pattern,
+ unsigned int len, int gfp_mask, int flags)
+{
+ int err = -ENOENT;
+ struct ts_config *conf;
+ struct ts_ops *ops;
+
+ ops = lookup_ts_algo(algo);
+#ifdef CONFIG_KMOD
+ /*
+ * Why not always autoload you may ask. Some users are
+ * in a situation where requesting a module may deadlock,
+ * especially when the module is located on a NFS mount.
+ */
+ if (ops == NULL && flags & TS_AUTOLOAD) {
+ request_module("ts_%s", algo);
+ ops = lookup_ts_algo(algo);
+ }
+#endif
+
+ if (ops == NULL)
+ goto errout;
+
+ conf = ops->init(pattern, len, gfp_mask);
+ if (IS_ERR(conf)) {
+ err = PTR_ERR(conf);
+ goto errout;
+ }
+
+ conf->ops = ops;
+ return conf;
+
+errout:
+ if (ops)
+ module_put(ops->owner);
+
+ return ERR_PTR(err);
+}
+
+/**
+ * textsearch_destroy - destroy a search configuration
+ * @conf: search configuration
+ *
+ * Releases all references of the configuration and frees
+ * up the memory.
+ */
+void textsearch_destroy(struct ts_config *conf)
+{
+ if (conf->ops) {
+ if (conf->ops->destroy)
+ conf->ops->destroy(conf);
+ module_put(conf->ops->owner);
+ }
+
+ kfree(conf);
+}
+
+EXPORT_SYMBOL(textsearch_register);
+EXPORT_SYMBOL(textsearch_unregister);
+EXPORT_SYMBOL(textsearch_prepare);
+EXPORT_SYMBOL(textsearch_find_continuous);
+EXPORT_SYMBOL(textsearch_destroy);
diff --git a/lib/ts_fsm.c b/lib/ts_fsm.c
new file mode 100644
index 00000000000..d27c0a07294
--- /dev/null
+++ b/lib/ts_fsm.c
@@ -0,0 +1,338 @@
+/*
+ * lib/ts_fsm.c A naive finite state machine text search approach
+ *
+ * This program 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.
+ *
+ * Authors: Thomas Graf <tgraf@suug.ch>
+ *
+ * ==========================================================================
+ *
+ * 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.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/textsearch.h>
+#include <linux/textsearch_fsm.h>
+
+struct ts_fsm
+{
+ unsigned int ntokens;
+ struct ts_fsm_token tokens[0];
+};
+
+/* other values derived from ctype.h */
+#define _A 0x100 /* ascii */
+#define _W 0x200 /* wildcard */
+
+/* Map to _ctype flags and some magic numbers */
+static u16 token_map[TS_FSM_TYPE_MAX+1] = {
+ [TS_FSM_SPECIFIC] = 0,
+ [TS_FSM_WILDCARD] = _W,
+ [TS_FSM_CNTRL] = _C,
+ [TS_FSM_LOWER] = _L,
+ [TS_FSM_UPPER] = _U,
+ [TS_FSM_PUNCT] = _P,
+ [TS_FSM_SPACE] = _S,
+ [TS_FSM_DIGIT] = _D,
+ [TS_FSM_XDIGIT] = _D | _X,
+ [TS_FSM_ALPHA] = _U | _L,
+ [TS_FSM_ALNUM] = _U | _L | _D,
+ [TS_FSM_PRINT] = _P | _U | _L | _D | _SP,
+ [TS_FSM_GRAPH] = _P | _U | _L | _D,
+ [TS_FSM_ASCII] = _A,
+};
+
+static u16 token_lookup_tbl[256] = {
+_W|_A|_C, _W|_A|_C, _W|_A|_C, _W|_A|_C, /* 0- 3 */
+_W|_A|_C, _W|_A|_C, _W|_A|_C, _W|_A|_C, /* 4- 7 */
+_W|_A|_C, _W|_A|_C|_S, _W|_A|_C|_S, _W|_A|_C|_S, /* 8- 11 */
+_W|_A|_C|_S, _W|_A|_C|_S, _W|_A|_C, _W|_A|_C, /* 12- 15 */
+_W|_A|_C, _W|_A|_C, _W|_A|_C, _W|_A|_C, /* 16- 19 */
+_W|_A|_C, _W|_A|_C, _W|_A|_C, _W|_A|_C, /* 20- 23 */
+_W|_A|_C, _W|_A|_C, _W|_A|_C, _W|_A|_C, /* 24- 27 */
+_W|_A|_C, _W|_A|_C, _W|_A|_C, _W|_A|_C, /* 28- 31 */
+_W|_A|_S|_SP, _W|_A|_P, _W|_A|_P, _W|_A|_P, /* 32- 35 */
+_W|_A|_P, _W|_A|_P, _W|_A|_P, _W|_A|_P, /* 36- 39 */
+_W|_A|_P, _W|_A|_P, _W|_A|_P, _W|_A|_P, /* 40- 43 */
+_W|_A|_P, _W|_A|_P, _W|_A|_P, _W|_A|_P, /* 44- 47 */
+_W|_A|_D, _W|_A|_D, _W|_A|_D, _W|_A|_D, /* 48- 51 */
+_W|_A|_D, _W|_A|_D, _W|_A|_D, _W|_A|_D, /* 52- 55 */
+_W|_A|_D, _W|_A|_D, _W|_A|_P, _W|_A|_P, /* 56- 59 */
+_W|_A|_P, _W|_A|_P, _W|_A|_P, _W|_A|_P, /* 60- 63 */
+_W|_A|_P, _W|_A|_U|_X, _W|_A|_U|_X, _W|_A|_U|_X, /* 64- 67 */
+_W|_A|_U|_X, _W|_A|_U|_X, _W|_A|_U|_X, _W|_A|_U, /* 68- 71 */
+_W|_A|_U, _W|_A|_U, _W|_A|_U, _W|_A|_U, /* 72- 75 */
+_W|_A|_U, _W|_A|_U, _W|_A|_U, _W|_A|_U, /* 76- 79 */
+_W|_A|_U, _W|_A|_U, _W|_A|_U, _W|_A|_U, /* 80- 83 */
+_W|_A|_U, _W|_A|_U, _W|_A|_U, _W|_A|_U, /* 84- 87 */
+_W|_A|_U, _W|_A|_U, _W|_A|_U, _W|_A|_P, /* 88- 91 */
+_W|_A|_P, _W|_A|_P, _W|_A|_P, _W|_A|_P, /* 92- 95 */
+_W|_A|_P, _W|_A|_L|_X, _W|_A|_L|_X, _W|_A|_L|_X, /* 96- 99 */
+_W|_A|_L|_X, _W|_A|_L|_X, _W|_A|_L|_X, _W|_A|_L, /* 100-103 */
+_W|_A|_L, _W|_A|_L, _W|_A|_L, _W|_A|_L, /* 104-107 */
+_W|_A|_L, _W|_A|_L, _W|_A|_L, _W|_A|_L, /* 108-111 */
+_W|_A|_L, _W|_A|_L, _W|_A|_L, _W|_A|_L, /* 112-115 */
+_W|_A|_L, _W|_A|_L, _W|_A|_L, _W|_A|_L, /* 116-119 */
+_W|_A|_L, _W|_A|_L, _W|_A|_L, _W|_A|_P, /* 120-123 */
+_W|_A|_P, _W|_A|_P, _W|_A|_P, _W|_A|_C, /* 124-127 */
+_W, _W, _W, _W, /* 128-131 */
+_W, _W, _W, _W, /* 132-135 */
+_W, _W, _W, _W, /* 136-139 */
+_W, _W, _W, _W, /* 140-143 */
+_W, _W, _W, _W, /* 144-147 */
+_W, _W, _W, _W, /* 148-151 */
+_W, _W, _W, _W, /* 152-155 */
+_W, _W, _W, _W, /* 156-159 */
+_W|_S|_SP, _W|_P, _W|_P, _W|_P, /* 160-163 */
+_W|_P, _W|_P, _W|_P, _W|_P, /* 164-167 */
+_W|_P, _W|_P, _W|_P, _W|_P, /* 168-171 */
+_W|_P, _W|_P, _W|_P, _W|_P, /* 172-175 */
+_W|_P, _W|_P, _W|_P, _W|_P, /* 176-179 */
+_W|_P, _W|_P, _W|_P, _W|_P, /* 180-183 */
+_W|_P, _W|_P, _W|_P, _W|_P, /* 184-187 */
+_W|_P, _W|_P, _W|_P, _W|_P, /* 188-191 */
+_W|_U, _W|_U, _W|_U, _W|_U, /* 192-195 */
+_W|_U, _W|_U, _W|_U, _W|_U, /* 196-199 */
+_W|_U, _W|_U, _W|_U, _W|_U, /* 200-203 */
+_W|_U, _W|_U, _W|_U, _W|_U, /* 204-207 */
+_W|_U, _W|_U, _W|_U, _W|_U, /* 208-211 */
+_W|_U, _W|_U, _W|_U, _W|_P, /* 212-215 */
+_W|_U, _W|_U, _W|_U, _W|_U, /* 216-219 */
+_W|_U, _W|_U, _W|_U, _W|_L, /* 220-223 */
+_W|_L, _W|_L, _W|_L, _W|_L, /* 224-227 */
+_W|_L, _W|_L, _W|_L, _W|_L, /* 228-231 */
+_W|_L, _W|_L, _W|_L, _W|_L, /* 232-235 */
+_W|_L, _W|_L, _W|_L, _W|_L, /* 236-239 */
+_W|_L, _W|_L, _W|_L, _W|_L, /* 240-243 */
+_W|_L, _W|_L, _W|_L, _W|_P, /* 244-247 */
+_W|_L, _W|_L, _W|_L, _W|_L, /* 248-251 */
+_W|_L, _W|_L, _W|_L, _W|_L}; /* 252-255 */
+
+static inline int match_token(struct ts_fsm_token *t, u8 d)
+{
+ if (t->type)
+ return (token_lookup_tbl[d] & t->type) != 0;
+ else
+ return t->value == d;
+}
+
+static unsigned int fsm_find(struct ts_config *conf, struct ts_state *state)
+{
+ struct ts_fsm *fsm = ts_config_priv(conf);
+ struct ts_fsm_token *cur = NULL, *next;
+ unsigned int match_start, block_idx = 0, tok_idx;
+ unsigned block_len = 0, strict, consumed = state->offset;
+ const u8 *data;
+
+#define GET_NEXT_BLOCK() \
+({ consumed += block_idx; \
+ block_idx = 0; \
+ block_len = conf->get_next_block(consumed, &data, conf, state); })
+
+#define TOKEN_MISMATCH() \
+ do { \
+ if (strict) \
+ goto no_match; \
+ block_idx++; \
+ goto startover; \
+ } while(0)
+
+#define end_of_data() unlikely(block_idx >= block_len && !GET_NEXT_BLOCK())
+
+ if (end_of_data())
+ goto no_match;
+
+ strict = fsm->tokens[0].recur != TS_FSM_HEAD_IGNORE;
+
+startover:
+ match_start = consumed + block_idx;
+
+ for (tok_idx = 0; tok_idx < fsm->ntokens; tok_idx++) {
+ cur = &fsm->tokens[tok_idx];
+
+ if (likely(tok_idx < (fsm->ntokens - 1)))
+ next = &fsm->tokens[tok_idx + 1];
+ else
+ next = NULL;
+
+ switch (cur->recur) {
+ case TS_FSM_SINGLE:
+ if (end_of_data())
+ goto no_match;
+
+ if (!match_token(cur, data[block_idx]))
+ TOKEN_MISMATCH();
+ break;
+
+ case TS_FSM_PERHAPS:
+ if (end_of_data() ||
+ !match_token(cur, data[block_idx]))
+ continue;
+ break;
+
+ case TS_FSM_MULTI:
+ if (end_of_data())
+ goto no_match;
+
+ if (!match_token(cur, data[block_idx]))
+ TOKEN_MISMATCH();
+
+ block_idx++;
+ /* fall through */
+
+ case TS_FSM_ANY:
+ if (next == NULL)
+ goto found_match;
+
+ if (end_of_data())
+ continue;
+
+ while (!match_token(next, data[block_idx])) {
+ if (!match_token(cur, data[block_idx]))
+ TOKEN_MISMATCH();
+ block_idx++;
+ if (end_of_data())
+ goto no_match;
+ }
+ continue;
+
+ /*
+ * Optimization: Prefer small local loop over jumping
+ * back and forth until garbage at head is munched.
+ */
+ case TS_FSM_HEAD_IGNORE:
+ if (end_of_data())
+ continue;
+
+ while (!match_token(next, data[block_idx])) {
+ /*
+ * Special case, don't start over upon
+ * a mismatch, give the user the
+ * chance to specify the type of data
+ * allowed to be ignored.
+ */
+ if (!match_token(cur, data[block_idx]))
+ goto no_match;
+
+ block_idx++;
+ if (end_of_data())
+ goto no_match;
+ }
+
+ match_start = consumed + block_idx;
+ continue;
+ }
+
+ block_idx++;
+ }
+
+ if (end_of_data())
+ goto found_match;
+
+no_match:
+ return UINT_MAX;
+
+found_match:
+ state->offset = consumed + block_idx;
+ return match_start;
+}
+
+static struct ts_config *fsm_init(const void *pattern, unsigned int len,
+ int gfp_mask)
+{
+ int i, err = -EINVAL;
+ struct ts_config *conf;
+ struct ts_fsm *fsm;
+ struct ts_fsm_token *tokens = (struct ts_fsm_token *) pattern;
+ unsigned int ntokens = len / sizeof(*tokens);
+ size_t priv_size = sizeof(*fsm) + len;
+
+ if (len % sizeof(struct ts_fsm_token) || ntokens < 1)
+ goto errout;
+
+ for (i = 0; i < ntokens; i++) {
+ struct ts_fsm_token *t = &tokens[i];
+
+ if (t->type > TS_FSM_TYPE_MAX || t->recur > TS_FSM_RECUR_MAX)
+ goto errout;
+
+ if (t->recur == TS_FSM_HEAD_IGNORE &&
+ (i != 0 || i == (ntokens - 1)))
+ goto errout;
+ }
+
+ conf = alloc_ts_config(priv_size, gfp_mask);
+ if (IS_ERR(conf))
+ return conf;
+
+ fsm = ts_config_priv(conf);
+ fsm->ntokens = ntokens;
+ memcpy(fsm->tokens, pattern, len);
+
+ for (i = 0; i < fsm->ntokens; i++) {
+ struct ts_fsm_token *t = &fsm->tokens[i];
+ t->type = token_map[t->type];
+ }
+
+ return conf;
+
+errout:
+ return ERR_PTR(err);
+}
+
+static void *fsm_get_pattern(struct ts_config *conf)
+{
+ struct ts_fsm *fsm = ts_config_priv(conf);
+ return fsm->tokens;
+}
+
+static unsigned int fsm_get_pattern_len(struct ts_config *conf)
+{
+ struct ts_fsm *fsm = ts_config_priv(conf);
+ return fsm->ntokens * sizeof(struct ts_fsm_token);
+}
+
+static struct ts_ops fsm_ops = {
+ .name = "fsm",
+ .find = fsm_find,
+ .init = fsm_init,
+ .get_pattern = fsm_get_pattern,
+ .get_pattern_len = fsm_get_pattern_len,
+ .owner = THIS_MODULE,
+ .list = LIST_HEAD_INIT(fsm_ops.list)
+};
+
+static int __init init_fsm(void)
+{
+ return textsearch_register(&fsm_ops);
+}
+
+static void __exit exit_fsm(void)
+{
+ textsearch_unregister(&fsm_ops);
+}
+
+MODULE_LICENSE("GPL");
+
+module_init(init_fsm);
+module_exit(exit_fsm);
diff --git a/lib/ts_kmp.c b/lib/ts_kmp.c
new file mode 100644
index 00000000000..73266b97558
--- /dev/null
+++ b/lib/ts_kmp.c
@@ -0,0 +1,145 @@
+/*
+ * lib/ts_kmp.c Knuth-Morris-Pratt text search implementation
+ *
+ * This program 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.
+ *
+ * Authors: Thomas Graf <tgraf@suug.ch>
+ *
+ * ==========================================================================
+ *
+ * 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
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/textsearch.h>
+
+struct ts_kmp
+{
+ u8 * pattern;
+ unsigned int pattern_len;
+ unsigned int prefix_tbl[0];
+};
+
+static unsigned int kmp_find(struct ts_config *conf, struct ts_state *state)
+{
+ struct ts_kmp *kmp = ts_config_priv(conf);
+ unsigned int i, q = 0, text_len, consumed = state->offset;
+ const u8 *text;
+
+ for (;;) {
+ text_len = conf->get_next_block(consumed, &text, conf, state);
+
+ if (unlikely(text_len == 0))
+ break;
+
+ for (i = 0; i < text_len; i++) {
+ while (q > 0 && kmp->pattern[q] != text[i])
+ q = kmp->prefix_tbl[q - 1];
+ if (kmp->pattern[q] == text[i])
+ q++;
+ if (unlikely(q == kmp->pattern_len)) {
+ state->offset = consumed + i + 1;
+ return state->offset - kmp->pattern_len;
+ }
+ }
+
+ consumed += text_len;
+ }
+
+ return UINT_MAX;
+}
+
+static inline void compute_prefix_tbl(const u8 *pattern, unsigned int len,
+ unsigned int *prefix_tbl)
+{
+ unsigned int k, q;
+
+ for (k = 0, q = 1; q < len; q++) {
+ while (k > 0 && pattern[k] != pattern[q])
+ k = prefix_tbl[k-1];
+ if (pattern[k] == pattern[q])
+ k++;
+ prefix_tbl[q] = k;
+ }
+}
+
+static struct ts_config *kmp_init(const void *pattern, unsigned int len,
+ int gfp_mask)
+{
+ struct ts_config *conf;
+ struct ts_kmp *kmp;
+ unsigned int prefix_tbl_len = len * sizeof(unsigned int);
+ size_t priv_size = sizeof(*kmp) + len + prefix_tbl_len;
+
+ conf = alloc_ts_config(priv_size, gfp_mask);
+ if (IS_ERR(conf))
+ return conf;
+
+ kmp = ts_config_priv(conf);
+ kmp->pattern_len = len;
+ compute_prefix_tbl(pattern, len, kmp->prefix_tbl);
+ kmp->pattern = (u8 *) kmp->prefix_tbl + prefix_tbl_len;
+ memcpy(kmp->pattern, pattern, len);
+
+ return conf;
+}
+
+static void *kmp_get_pattern(struct ts_config *conf)
+{
+ struct ts_kmp *kmp = ts_config_priv(conf);
+ return kmp->pattern;
+}
+
+static unsigned int kmp_get_pattern_len(struct ts_config *conf)
+{
+ struct ts_kmp *kmp = ts_config_priv(conf);
+ return kmp->pattern_len;
+}
+
+static struct ts_ops kmp_ops = {
+ .name = "kmp",
+ .find = kmp_find,
+ .init = kmp_init,
+ .get_pattern = kmp_get_pattern,
+ .get_pattern_len = kmp_get_pattern_len,
+ .owner = THIS_MODULE,
+ .list = LIST_HEAD_INIT(kmp_ops.list)
+};
+
+static int __init init_kmp(void)
+{
+ return textsearch_register(&kmp_ops);
+}
+
+static void __exit exit_kmp(void)
+{
+ textsearch_unregister(&kmp_ops);
+}
+
+MODULE_LICENSE("GPL");
+
+module_init(init_kmp);
+module_exit(exit_kmp);