glibc/string/strxfrm_l.c
Siddhesh Poyarekar 30891f35fa Remove "Contributed by" lines
We stopped adding "Contributed by" or similar lines in sources in 2012
in favour of git logs and keeping the Contributors section of the
glibc manual up to date.  Removing these lines makes the license
header a bit more consistent across files and also removes the
possibility of error in attribution when license blocks or files are
copied across since the contributed-by lines don't actually reflect
reality in those cases.

Move all "Contributed by" and similar lines (Written by, Test by,
etc.) into a new file CONTRIBUTED-BY to retain record of these
contributions.  These contributors are also mentioned in
manual/contrib.texi, so we just maintain this additional record as a
courtesy to the earlier developers.

The following scripts were used to filter a list of files to edit in
place and to clean up the CONTRIBUTED-BY file respectively.  These
were not added to the glibc sources because they're not expected to be
of any use in future given that this is a one time task:

https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dc
https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-09-03 22:06:44 +05:30

747 lines
18 KiB
C

/* Copyright (C) 1995-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <assert.h>
#include <langinfo.h>
#include <locale.h>
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <sys/param.h>
#ifndef STRING_TYPE
# define STRING_TYPE char
# define USTRING_TYPE unsigned char
# define STRXFRM __strxfrm_l
# define STRLEN strlen
# define STPNCPY __stpncpy
# define WEIGHT_H "../locale/weight.h"
# define SUFFIX MB
# define L(arg) arg
#endif
#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
/* We need UTF-8 encoding of numbers. */
static int
utf8_encode (char *buf, int val)
{
int retval;
if (val < 0x80)
{
*buf++ = (char) val;
retval = 1;
}
else
{
int step;
for (step = 2; step < 6; ++step)
if ((val & (~(uint32_t)0 << (5 * step + 1))) == 0)
break;
retval = step;
*buf = (unsigned char) (~0xff >> step);
--step;
do
{
buf[step] = 0x80 | (val & 0x3f);
val >>= 6;
}
while (--step > 0);
*buf |= val;
}
return retval;
}
#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++];
}
*weight_idx = idx;
return len;
}
static int
find_position (const USTRING_TYPE *us, const locale_data_t *l_data,
const int pass)
{
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 = 0;
size_t last_needed;
/* Now the passes over the weights. */
for (pass = 0; pass < l_data->nrules; ++pass)
{
size_t backw_len = 0;
last_needed = needed;
const USTRING_TYPE *cur = usrc;
const USTRING_TYPE *backw_start = NULL;
/* 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);
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];
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;
}
needed += backw_len;
backw_start = NULL;
backw_len = 0;
}
/* 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;
}
/* 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)
{
/* Remove the \1 byte. */
if (--needed <= n)
dest[needed - 1] = L('\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. */
for (pass = 0; pass < nrules; ++pass)
{
size_t backw_stop = ~0ul;
int rule = rulesets[rulearr[0] * nrules + pass];
/* We assume that if a rule has defined `position' in one section
this is true for all of them. */
int position = rule & sort_position;
last_needed = needed;
if (position == 0)
{
for (idxcnt = 0; idxcnt < idxmax; ++idxcnt)
{
if ((rule & sort_forward) != 0)
{
size_t len;
if (backw_stop != ~0ul)
{
/* Handle the pushed elements now. */
size_t backw;
for (backw = idxcnt; backw > backw_stop; )
{
--backw;
len = weights[idxarr[backw]++];
if (needed + len < n)
while (len-- > 0)
dest[needed++] = weights[idxarr[backw]++];
else
{
/* No more characters fit into the buffer. */
needed += len;
idxarr[backw] += len;
}
}
backw_stop = ~0ul;
}
/* Now handle the forward element. */
len = weights[idxarr[idxcnt]++];
if (needed + len < n)
while (len-- > 0)
dest[needed++] = weights[idxarr[idxcnt]++];
else
{
/* No more characters fit into the buffer. */
needed += len;
idxarr[idxcnt] += len;
}
}
else
{
/* Remember where the backwards series started. */
if (backw_stop == ~0ul)
backw_stop = idxcnt;
}
rule = rulesets[rulearr[idxcnt + 1] * nrules + pass];
}
if (backw_stop != ~0ul)
{
/* Handle the pushed elements now. */
size_t backw;
backw = idxcnt;
while (backw > backw_stop)
{
size_t len = weights[idxarr[--backw]++];
if (needed + len < n)
while (len-- > 0)
dest[needed++] = weights[idxarr[backw]++];
else
{
/* No more characters fit into the buffer. */
needed += len;
idxarr[backw] += len;
}
}
}
}
else
{
int val = 1;
#ifndef WIDE_CHAR_VERSION
char buf[7];
size_t buflen;
#endif
size_t i;
for (idxcnt = 0; idxcnt < idxmax; ++idxcnt)
{
if ((rule & sort_forward) != 0)
{
size_t len;
if (backw_stop != ~0ul)
{
/* Handle the pushed elements now. */
size_t backw;
for (backw = idxcnt; backw > backw_stop; )
{
--backw;
len = weights[idxarr[backw]++];
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] =
weights[idxarr[backw] + 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] =
weights[idxarr[backw] + i];
}
needed += buflen + len;
#endif
idxarr[backw] += len;
val = 1;
}
else
++val;
}
backw_stop = ~0ul;
}
/* Now handle the forward element. */
len = weights[idxarr[idxcnt]++];
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] =
weights[idxarr[idxcnt] + 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] =
weights[idxarr[idxcnt] + i];
}
needed += buflen + len;
#endif
idxarr[idxcnt] += len;
val = 1;
}
else
/* Note that we don't have to increment `idxarr[idxcnt]'
since the length is zero. */
++val;
}
else
{
/* Remember where the backwards series started. */
if (backw_stop == ~0ul)
backw_stop = idxcnt;
}
rule = rulesets[rulearr[idxcnt + 1] * nrules + pass];
}
if (backw_stop != ~0ul)
{
/* Handle the pushed elements now. */
size_t backw;
backw = idxmax - 1;
while (backw > backw_stop)
{
size_t len = weights[idxarr[--backw]++];
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] =
weights[idxarr[backw] + 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] =
weights[idxarr[backw] + i];
}
needed += buflen + len;
#endif
idxarr[backw] += len;
val = 1;
}
else
++val;
}
}
}
/* Finally store the byte to separate the passes or terminate
the string. */
if (needed < n)
dest[needed] = pass + 1 < nrules ? L('\1') : L('\0');
++needed;
}
/* 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)
{
/* Remove the \1 byte. */
if (--needed <= n)
dest[needed - 1] = L('\0');
}
/* 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 indices. */
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
weak_alias (__strxfrm_l, strxfrm_l)
#endif