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authorLeonhard Holz <leonhard.holz@web.de>2015-01-13 11:33:56 +0530
committerMike Frysinger <vapier@gentoo.org>2015-02-16 05:23:17 -0500
commitf9e0f439b72e0b2fb035be1bc60aaceeed7f6ed0 (patch)
tree87ec52e7a403d4632387e7cd9c9d0fd340b7f1d2
parentb0694b9e98ee64cb25490de0921ce307f3872749 (diff)
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Fix memory handling in strxfrm_l [BZ #16009]
[Modified from the original email by Siddhesh Poyarekar] This patch solves bug #16009 by implementing an additional path in strxfrm that does not depend on caching the weight and rule indices. In detail the following changed: * The old main loop was factored out of strxfrm_l into the function do_xfrm_cached to be able to alternativly use the non-caching version do_xfrm. * strxfrm_l allocates a a fixed size array on the stack. If this is not sufficiant to store the weight and rule indices, the non-caching path is taken. As the cache size is not dependent on the input there can be no problems with integer overflows or stack allocations greater than __MAX_ALLOCA_CUTOFF. Note that malloc-ing is not possible because the definition of strxfrm does not allow an oom errorhandling. * The uncached path determines the weight and rule index for every char and for every pass again. * Passing all the locale data array by array resulted in very long parameter lists, so I introduced a structure that holds them. * Checking for zero src string has been moved a bit upwards, it is before the locale data initialization now. * To verify that the non-caching path works correct I added a test run to localedata/sort-test.sh & localedata/xfrm-test.c where all strings are patched up with spaces so that they are too large for the caching path. (cherry picked from commit 0f9e585480edcdf1e30dc3d79e24b84aeee516fa) Conflicts: ChangeLog NEWS
-rw-r--r--ChangeLog16
-rw-r--r--NEWS2
-rw-r--r--localedata/sort-test.sh7
-rw-r--r--localedata/xfrm-test.c52
-rw-r--r--string/strxfrm_l.c488
5 files changed, 464 insertions, 101 deletions
diff --git a/ChangeLog b/ChangeLog
index dbf7e86950f..7a2e6c98841 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,19 @@
+2015-02-16 Leonhard Holz <leonhard.holz@web.de>
+
+ [BZ #16009]
+ * string/strxfrm_l.c (STRXFRM): Allocate fixed size cache for
+ weights and rules. Use do_xfrm_cached if data fits in cache,
+ do_xfrm otherwise. Moved former main loop to...
+ * (do_xfrm_cached): New function.
+ * (do_xfrm): Non-caching version of do_xfrm_cached. Uses
+ find_idx, find_position and stack_push.
+ * (find_idx): New function.
+ * (find_position): Likewise.
+ * localedata/sort-test.sh: Added test run for do_xfrm.
+ * localedata/xfrm-test.c (main): Added command line option
+ -nocache to run the test with strings that are too large for
+ the STRXFRM cache.
+
2015-02-16 Kostya Serebryany <konstantin.s.serebryany@gmail.com>
Roland McGrath <roland@hack.frob.com>
diff --git a/NEWS b/NEWS
index 9bc835c4d17..f5788058bd1 100644
--- a/NEWS
+++ b/NEWS
@@ -9,7 +9,7 @@ Version 2.20.1
* The following bugs are resolved with this release:
- 16617, 17266, 17370, 17371, 17460, 17485, 17555, 17625, 17630.
+ 16009, 16617, 17266, 17370, 17371, 17460, 17485, 17555, 17625, 17630.
* CVE-2104-7817 The wordexp function could ignore the WRDE_NOCMD flag
under certain input conditions resulting in the execution of a shell for
diff --git a/localedata/sort-test.sh b/localedata/sort-test.sh
index e37129a032d..3cb57fb45c3 100644
--- a/localedata/sort-test.sh
+++ b/localedata/sort-test.sh
@@ -53,11 +53,18 @@ for l in $lang; do
${common_objpfx}localedata/xfrm-test $id < $cns.in \
> ${common_objpfx}localedata/$cns.xout || here=1
cmp -s $cns.in ${common_objpfx}localedata/$cns.xout || here=1
+ ${test_program_prefix_before_env} \
+ ${run_program_env} \
+ LC_ALL=$l ${test_program_prefix_after_env} \
+ ${common_objpfx}localedata/xfrm-test $id -nocache < $cns.in \
+ > ${common_objpfx}localedata/$cns.nocache.xout || here=1
+ cmp -s $cns.in ${common_objpfx}localedata/$cns.nocache.xout || here=1
if test $here -eq 0; then
echo "$l xfrm-test OK"
else
echo "$l xfrm-test FAIL"
diff -u $cns.in ${common_objpfx}localedata/$cns.xout | sed 's/^/ /'
+ diff -u $cns.in ${common_objpfx}localedata/$cns.nocache.xout | sed 's/^/ /'
status=1
fi
done
diff --git a/localedata/xfrm-test.c b/localedata/xfrm-test.c
index d2aba7d26e5..5cf29f60c9b 100644
--- a/localedata/xfrm-test.c
+++ b/localedata/xfrm-test.c
@@ -23,7 +23,10 @@
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <stdbool.h>
+/* Keep in sync with string/strxfrm_l.c. */
+#define SMALL_STR_SIZE 4095
struct lines
{
@@ -37,6 +40,7 @@ int
main (int argc, char *argv[])
{
int result = 0;
+ bool nocache = false;
size_t nstrings, nstrings_max;
struct lines *strings;
char *line = NULL;
@@ -44,7 +48,18 @@ main (int argc, char *argv[])
size_t n;
if (argc < 2)
- error (1, 0, "usage: %s <random seed>", argv[0]);
+ error (1, 0, "usage: %s <random seed> [-nocache]", argv[0]);
+
+ if (argc == 3)
+ {
+ if (strcmp (argv[2], "-nocache") == 0)
+ nocache = true;
+ else
+ {
+ printf ("Unknown option %s!\n", argv[2]);
+ exit (1);
+ }
+ }
setlocale (LC_ALL, "");
@@ -59,9 +74,9 @@ main (int argc, char *argv[])
while (1)
{
- char saved, *newp;
- int needed;
- int l;
+ char saved, *word, *newp;
+ size_t l, line_len, needed;
+
if (getline (&line, &len, stdin) < 0)
break;
@@ -83,10 +98,35 @@ main (int argc, char *argv[])
saved = line[l];
line[l] = '\0';
- needed = strxfrm (NULL, line, 0);
+
+ if (nocache)
+ {
+ line_len = strlen (line);
+ word = malloc (line_len + SMALL_STR_SIZE + 1);
+ if (word == NULL)
+ {
+ printf ("malloc failed: %m\n");
+ exit (1);
+ }
+ memset (word, ' ', SMALL_STR_SIZE);
+ memcpy (word + SMALL_STR_SIZE, line, line_len);
+ word[line_len + SMALL_STR_SIZE] = '\0';
+ }
+ else
+ word = line;
+
+ needed = strxfrm (NULL, word, 0);
newp = malloc (needed + 1);
- strxfrm (newp, line, needed + 1);
+ if (newp == NULL)
+ {
+ printf ("malloc failed: %m\n");
+ exit (1);
+ }
+ strxfrm (newp, word, needed + 1);
strings[nstrings].xfrm = newp;
+
+ if (nocache)
+ free (word);
line[l] = saved;
++nstrings;
}
diff --git a/string/strxfrm_l.c b/string/strxfrm_l.c
index 2d3f1bd5fc7..95ffd6fdf1d 100644
--- a/string/strxfrm_l.c
+++ b/string/strxfrm_l.c
@@ -40,9 +40,24 @@
#define CONCAT(a,b) CONCAT1(a,b)
#define CONCAT1(a,b) a##b
+/* Maximum string size that is calculated with cached indices. Right now this
+ is an arbitrary value open to optimizations. SMALL_STR_SIZE * 4 has to be
+ lower than __MAX_ALLOCA_CUTOFF. Keep localedata/xfrm-test.c in sync. */
+#define SMALL_STR_SIZE 4095
+
#include "../locale/localeinfo.h"
#include WEIGHT_H
+/* Group locale data for shorter parameter lists. */
+typedef struct
+{
+ uint_fast32_t nrules;
+ unsigned char *rulesets;
+ USTRING_TYPE *weights;
+ int32_t *table;
+ USTRING_TYPE *extra;
+ int32_t *indirect;
+} locale_data_t;
#ifndef WIDE_CHAR_VERSION
@@ -81,113 +96,325 @@ utf8_encode (char *buf, int val)
}
#endif
+/* Find next weight and rule index. Inlined since called for every char. */
+static __always_inline size_t
+find_idx (const USTRING_TYPE **us, int32_t *weight_idx,
+ unsigned char *rule_idx, const locale_data_t *l_data, const int pass)
+{
+ int32_t tmp = findidx (l_data->table, l_data->indirect, l_data->extra, us,
+ -1);
+ *rule_idx = tmp >> 24;
+ int32_t idx = tmp & 0xffffff;
+ size_t len = l_data->weights[idx++];
+
+ /* Skip over indices of previous levels. */
+ for (int i = 0; i < pass; i++)
+ {
+ idx += len;
+ len = l_data->weights[idx++];
+ }
-size_t
-STRXFRM (STRING_TYPE *dest, const STRING_TYPE *src, size_t n, __locale_t l)
+ *weight_idx = idx;
+ return len;
+}
+
+static int
+find_position (const USTRING_TYPE *us, const locale_data_t *l_data,
+ const int pass)
{
- struct __locale_data *current = l->__locales[LC_COLLATE];
- uint_fast32_t nrules = current->values[_NL_ITEM_INDEX (_NL_COLLATE_NRULES)].word;
- /* We don't assign the following values right away since it might be
- unnecessary in case there are no rules. */
- const unsigned char *rulesets;
- const int32_t *table;
- const USTRING_TYPE *weights;
- const USTRING_TYPE *extra;
- const int32_t *indirect;
+ int32_t weight_idx;
+ unsigned char rule_idx;
+ const USTRING_TYPE *usrc = us;
+
+ find_idx (&usrc, &weight_idx, &rule_idx, l_data, pass);
+ return l_data->rulesets[rule_idx * l_data->nrules + pass] & sort_position;
+}
+
+/* Do the transformation. */
+static size_t
+do_xfrm (const USTRING_TYPE *usrc, STRING_TYPE *dest, size_t n,
+ const locale_data_t *l_data)
+{
+ int32_t weight_idx;
+ unsigned char rule_idx;
uint_fast32_t pass;
- size_t needed;
+ size_t needed = 0;
size_t last_needed;
- const USTRING_TYPE *usrc;
- size_t srclen = STRLEN (src);
- int32_t *idxarr;
- unsigned char *rulearr;
- size_t idxmax;
- size_t idxcnt;
- int use_malloc;
- if (nrules == 0)
+ /* Now the passes over the weights. */
+ for (pass = 0; pass < l_data->nrules; ++pass)
{
- if (n != 0)
- STPNCPY (dest, src, MIN (srclen + 1, n));
+ size_t backw_len = 0;
+ last_needed = needed;
+ const USTRING_TYPE *cur = usrc;
+ const USTRING_TYPE *backw_start = NULL;
- return srclen;
- }
+ /* We assume that if a rule has defined `position' in one section
+ this is true for all of them. */
+ int position = find_position (cur, l_data, pass);
- rulesets = (const unsigned char *)
- current->values[_NL_ITEM_INDEX (_NL_COLLATE_RULESETS)].string;
- table = (const int32_t *)
- current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_TABLE,SUFFIX))].string;
- weights = (const USTRING_TYPE *)
- current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_WEIGHT,SUFFIX))].string;
- extra = (const USTRING_TYPE *)
- current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_EXTRA,SUFFIX))].string;
- indirect = (const int32_t *)
- current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_INDIRECT,SUFFIX))].string;
- use_malloc = 0;
+ if (position == 0)
+ {
+ while (*cur != L('\0'))
+ {
+ const USTRING_TYPE *pos = cur;
+ size_t len = find_idx (&cur, &weight_idx, &rule_idx, l_data,
+ pass);
+ int rule = l_data->rulesets[rule_idx * l_data->nrules + pass];
- assert (((uintptr_t) table) % __alignof__ (table[0]) == 0);
- assert (((uintptr_t) weights) % __alignof__ (weights[0]) == 0);
- assert (((uintptr_t) extra) % __alignof__ (extra[0]) == 0);
- assert (((uintptr_t) indirect) % __alignof__ (indirect[0]) == 0);
+ if ((rule & sort_forward) != 0)
+ {
+ /* Handle the pushed backward sequence. */
+ if (backw_start != NULL)
+ {
+ for (size_t i = backw_len; i > 0; )
+ {
+ int32_t weight_idx;
+ unsigned char rule_idx;
+ size_t len = find_idx (&backw_start, &weight_idx,
+ &rule_idx, l_data, pass);
+ if (needed + i < n)
+ for (size_t j = len; j > 0; j--)
+ dest[needed + i - j] =
+ l_data->weights[weight_idx++];
+
+ i -= len;
+ }
- /* Handle an empty string as a special case. */
- if (srclen == 0)
- {
- if (n != 0)
- *dest = L('\0');
- return 0;
- }
+ needed += backw_len;
+ backw_start = NULL;
+ backw_len = 0;
+ }
- /* We need the elements of the string as unsigned values since they
- are used as indeces. */
- usrc = (const USTRING_TYPE *) src;
-
- /* Perform the first pass over the string and while doing this find
- and store the weights for each character. Since we want this to
- be as fast as possible we are using `alloca' to store the temporary
- values. But since there is no limit on the length of the string
- we have to use `malloc' if the string is too long. We should be
- very conservative here. */
- if (! __libc_use_alloca ((srclen + 1) * (sizeof (int32_t) + 1)))
- {
- idxarr = (int32_t *) malloc ((srclen + 1) * (sizeof (int32_t) + 1));
- rulearr = (unsigned char *) &idxarr[srclen];
-
- if (idxarr == NULL)
- /* No memory. Well, go with the stack then.
-
- XXX Once this implementation is stable we will handle this
- differently. Instead of precomputing the indeces we will
- do this in time. This means, though, that this happens for
- every pass again. */
- goto try_stack;
- use_malloc = 1;
- }
- else
- {
- try_stack:
- idxarr = (int32_t *) alloca (srclen * sizeof (int32_t));
- rulearr = (unsigned char *) alloca (srclen + 1);
+ /* Now handle the forward element. */
+ if (needed + len < n)
+ while (len-- > 0)
+ dest[needed++] = l_data->weights[weight_idx++];
+ else
+ /* No more characters fit into the buffer. */
+ needed += len;
+ }
+ else
+ {
+ /* Remember start of the backward sequence & track length. */
+ if (backw_start == NULL)
+ backw_start = pos;
+ backw_len += len;
+ }
+ }
+
+
+ /* Handle the pushed backward sequence. */
+ if (backw_start != NULL)
+ {
+ for (size_t i = backw_len; i > 0; )
+ {
+ size_t len = find_idx (&backw_start, &weight_idx, &rule_idx,
+ l_data, pass);
+ if (needed + i < n)
+ for (size_t j = len; j > 0; j--)
+ dest[needed + i - j] =
+ l_data->weights[weight_idx++];
+
+ i -= len;
+ }
+
+ needed += backw_len;
+ }
+ }
+ else
+ {
+ int val = 1;
+#ifndef WIDE_CHAR_VERSION
+ char buf[7];
+ size_t buflen;
+#endif
+ size_t i;
+
+ while (*cur != L('\0'))
+ {
+ const USTRING_TYPE *pos = cur;
+ size_t len = find_idx (&cur, &weight_idx, &rule_idx, l_data,
+ pass);
+ int rule = l_data->rulesets[rule_idx * l_data->nrules + pass];
+
+ if ((rule & sort_forward) != 0)
+ {
+ /* Handle the pushed backward sequence. */
+ if (backw_start != NULL)
+ {
+ for (size_t p = backw_len; p > 0; p--)
+ {
+ size_t len;
+ int32_t weight_idx;
+ unsigned char rule_idx;
+ const USTRING_TYPE *backw_cur = backw_start;
+
+ /* To prevent a warning init the used vars. */
+ len = find_idx (&backw_cur, &weight_idx,
+ &rule_idx, l_data, pass);
+
+ for (i = 1; i < p; i++)
+ len = find_idx (&backw_cur, &weight_idx,
+ &rule_idx, l_data, pass);
+
+ if (len != 0)
+ {
+#ifdef WIDE_CHAR_VERSION
+ if (needed + 1 + len < n)
+ {
+ dest[needed] = val;
+ for (i = 0; i < len; ++i)
+ dest[needed + 1 + i] =
+ l_data->weights[weight_idx + i];
+ }
+ needed += 1 + len;
+#else
+ buflen = utf8_encode (buf, val);
+ if (needed + buflen + len < n)
+ {
+ for (i = 0; i < buflen; ++i)
+ dest[needed + i] = buf[i];
+ for (i = 0; i < len; ++i)
+ dest[needed + buflen + i] =
+ l_data->weights[weight_idx + i];
+ }
+ needed += buflen + len;
+#endif
+ val = 1;
+ }
+ else
+ ++val;
+ }
+
+ backw_start = NULL;
+ backw_len = 0;
+ }
+
+ /* Now handle the forward element. */
+ if (len != 0)
+ {
+#ifdef WIDE_CHAR_VERSION
+ if (needed + 1 + len < n)
+ {
+ dest[needed] = val;
+ for (i = 0; i < len; ++i)
+ dest[needed + 1 + i] =
+ l_data->weights[weight_idx + i];
+ }
+ needed += 1 + len;
+#else
+ buflen = utf8_encode (buf, val);
+ if (needed + buflen + len < n)
+ {
+ for (i = 0; i < buflen; ++i)
+ dest[needed + i] = buf[i];
+ for (i = 0; i < len; ++i)
+ dest[needed + buflen + i] =
+ l_data->weights[weight_idx + i];
+ }
+ needed += buflen + len;
+#endif
+ val = 1;
+ }
+ else
+ ++val;
+ }
+ else
+ {
+ /* Remember start of the backward sequence & track length. */
+ if (backw_start == NULL)
+ backw_start = pos;
+ backw_len++;
+ }
+ }
+
+ /* Handle the pushed backward sequence. */
+ if (backw_start != NULL)
+ {
+ for (size_t p = backw_len; p > 0; p--)
+ {
+ size_t len;
+ int32_t weight_idx;
+ unsigned char rule_idx;
+ const USTRING_TYPE *backw_cur = backw_start;
+
+ /* To prevent a warning init the used vars. */
+ len = find_idx (&backw_cur, &weight_idx,
+ &rule_idx, l_data, pass);
+
+ for (i = 1; i < p; i++)
+ len = find_idx (&backw_cur, &weight_idx,
+ &rule_idx, l_data, pass);
+
+ if (len != 0)
+ {
+#ifdef WIDE_CHAR_VERSION
+ if (needed + 1 + len < n)
+ {
+ dest[needed] = val;
+ for (i = 0; i < len; ++i)
+ dest[needed + 1 + i] =
+ l_data->weights[weight_idx + i];
+ }
+ needed += 1 + len;
+#else
+ buflen = utf8_encode (buf, val);
+ if (needed + buflen + len < n)
+ {
+ for (i = 0; i < buflen; ++i)
+ dest[needed + i] = buf[i];
+ for (i = 0; i < len; ++i)
+ dest[needed + buflen + i] =
+ l_data->weights[weight_idx + i];
+ }
+ needed += buflen + len;
+#endif
+ val = 1;
+ }
+ else
+ ++val;
+ }
+ }
+ }
+
+ /* Finally store the byte to separate the passes or terminate
+ the string. */
+ if (needed < n)
+ dest[needed] = pass + 1 < l_data->nrules ? L('\1') : L('\0');
+ ++needed;
}
- idxmax = 0;
- do
+ /* This is a little optimization: many collation specifications have
+ a `position' rule at the end and if no non-ignored character
+ is found the last \1 byte is immediately followed by a \0 byte
+ signalling this. We can avoid the \1 byte(s). */
+ if (needed > 2 && needed == last_needed + 1)
{
- int32_t tmp = findidx (table, indirect, extra, &usrc, -1);
- rulearr[idxmax] = tmp >> 24;
- idxarr[idxmax] = tmp & 0xffffff;
-
- ++idxmax;
+ /* Remove the \1 byte. */
+ if (--needed <= n)
+ dest[needed - 1] = L('\0');
}
- while (*usrc != L('\0'));
- /* This element is only read, the value never used but to determine
- another value which then is ignored. */
- rulearr[idxmax] = '\0';
+ /* Return the number of bytes/words we need, but don't count the NUL
+ byte/word at the end. */
+ return needed - 1;
+}
+
+/* Do the transformation using weight-index and rule cache. */
+static size_t
+do_xfrm_cached (STRING_TYPE *dest, size_t n, const locale_data_t *l_data,
+ size_t idxmax, int32_t *idxarr, const unsigned char *rulearr)
+{
+ uint_fast32_t nrules = l_data->nrules;
+ unsigned char *rulesets = l_data->rulesets;
+ USTRING_TYPE *weights = l_data->weights;
+ uint_fast32_t pass;
+ size_t needed = 0;
+ size_t last_needed;
+ size_t idxcnt;
- /* Now the passes over the weights. We now use the indeces we found
- before. */
- needed = 0;
+ /* Now the passes over the weights. */
for (pass = 0; pass < nrules; ++pass)
{
size_t backw_stop = ~0ul;
@@ -433,14 +660,87 @@ STRXFRM (STRING_TYPE *dest, const STRING_TYPE *src, size_t n, __locale_t l)
dest[needed - 1] = L('\0');
}
- /* Free the memory if needed. */
- if (use_malloc)
- free (idxarr);
-
/* Return the number of bytes/words we need, but don't count the NUL
byte/word at the end. */
return needed - 1;
}
+
+size_t
+STRXFRM (STRING_TYPE *dest, const STRING_TYPE *src, size_t n, __locale_t l)
+{
+ locale_data_t l_data;
+ struct __locale_data *current = l->__locales[LC_COLLATE];
+ l_data.nrules = current->values[_NL_ITEM_INDEX (_NL_COLLATE_NRULES)].word;
+
+ /* Handle byte comparison case. */
+ if (l_data.nrules == 0)
+ {
+ size_t srclen = STRLEN (src);
+
+ if (n != 0)
+ STPNCPY (dest, src, MIN (srclen + 1, n));
+
+ return srclen;
+ }
+
+ /* Handle an empty string, code hereafter relies on strlen (src) > 0. */
+ if (*src == L('\0'))
+ {
+ if (n != 0)
+ *dest = L('\0');
+ return 0;
+ }
+
+ /* Get the locale data. */
+ l_data.rulesets = (unsigned char *)
+ current->values[_NL_ITEM_INDEX (_NL_COLLATE_RULESETS)].string;
+ l_data.table = (int32_t *)
+ current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_TABLE,SUFFIX))].string;
+ l_data.weights = (USTRING_TYPE *)
+ current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_WEIGHT,SUFFIX))].string;
+ l_data.extra = (USTRING_TYPE *)
+ current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_EXTRA,SUFFIX))].string;
+ l_data.indirect = (int32_t *)
+ current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_INDIRECT,SUFFIX))].string;
+
+ assert (((uintptr_t) l_data.table) % __alignof__ (l_data.table[0]) == 0);
+ assert (((uintptr_t) l_data.weights) % __alignof__ (l_data.weights[0]) == 0);
+ assert (((uintptr_t) l_data.extra) % __alignof__ (l_data.extra[0]) == 0);
+ assert (((uintptr_t) l_data.indirect) % __alignof__ (l_data.indirect[0]) == 0);
+
+ /* We need the elements of the string as unsigned values since they
+ are used as indeces. */
+ const USTRING_TYPE *usrc = (const USTRING_TYPE *) src;
+
+ /* Allocate cache for small strings on the stack and fill it with weight and
+ rule indices. If the cache size is not sufficient, continue with the
+ uncached xfrm version. */
+ size_t idxmax = 0;
+ const USTRING_TYPE *cur = usrc;
+ int32_t *idxarr = alloca (SMALL_STR_SIZE * sizeof (int32_t));
+ unsigned char *rulearr = alloca (SMALL_STR_SIZE + 1);
+
+ do
+ {
+ int32_t tmp = findidx (l_data.table, l_data.indirect, l_data.extra, &cur,
+ -1);
+ rulearr[idxmax] = tmp >> 24;
+ idxarr[idxmax] = tmp & 0xffffff;
+
+ ++idxmax;
+ }
+ while (*cur != L('\0') && idxmax < SMALL_STR_SIZE);
+
+ /* This element is only read, the value never used but to determine
+ another value which then is ignored. */
+ rulearr[idxmax] = '\0';
+
+ /* Do the transformation. */
+ if (*cur == L('\0'))
+ return do_xfrm_cached (dest, n, &l_data, idxmax, idxarr, rulearr);
+ else
+ return do_xfrm (usrc, dest, n, &l_data);
+}
libc_hidden_def (STRXFRM)
#ifndef WIDE_CHAR_VERSION