localeutil.h

/* stringlib: locale related helpers implementation */

#ifndefSTRINGLIB_LOCALEUTIL_H
#defineSTRINGLIB_LOCALEUTIL_H

#include<locale.h>

#defineMAX(x, y) ((x) < (y) ? (y) : (x))
#defineMIN(x, y) ((x) < (y) ? (x) : (y))

typedefstruct {
constchar*grouping;
charprevious;
Py_ssize_ti; /* Where we're currently pointing in grouping. */
} GroupGenerator;

staticvoid
_GroupGenerator_init(GroupGenerator*self, constchar*grouping)
{
self->grouping=grouping;
self->i=0;
self->previous=0;
}

/* Returns the next grouping, or 0 to signify end. */
staticPy_ssize_t
_GroupGenerator_next(GroupGenerator*self)
{
/* Note that we don't really do much error checking here. If a
 grouping string contains just CHAR_MAX, for example, then just
 terminate the generator. That shouldn't happen, but at least we
 fail gracefully. */
switch (self->grouping[self->i]) {
case0:
returnself->previous;
caseCHAR_MAX:
/* Stop the generator. */
return0;
default: {
charch=self->grouping[self->i];
self->previous=ch;
self->i++;
return (Py_ssize_t)ch;
 }
 }
}

/* Fill in some digits, leading zeros, and thousands separator. All
 are optional, depending on when we're called. */
staticvoid
fill(STRINGLIB_CHAR**digits_end, STRINGLIB_CHAR**buffer_end,
Py_ssize_tn_chars, Py_ssize_tn_zeros, constchar*thousands_sep,
Py_ssize_tthousands_sep_len)
{
#ifSTRINGLIB_IS_UNICODE
Py_ssize_ti;
#endif

if (thousands_sep) {
*buffer_end-=thousands_sep_len;

/* Copy the thousands_sep chars into the buffer. */
#ifSTRINGLIB_IS_UNICODE
/* Convert from the char's of the thousands_sep from
 the locale into unicode. */
for (i=0; i<thousands_sep_len; ++i)
 (*buffer_end)[i] =thousands_sep[i];
#else
/* No conversion, just memcpy the thousands_sep. */
memcpy(*buffer_end, thousands_sep, thousands_sep_len);
#endif
 }

*buffer_end-=n_chars;
*digits_end-=n_chars;
memcpy(*buffer_end, *digits_end, n_chars*sizeof(STRINGLIB_CHAR));

*buffer_end-=n_zeros;
STRINGLIB_FILL(*buffer_end, '0', n_zeros);
}

/**
 * _Py_InsertThousandsGrouping:
 * @buffer: A pointer to the start of a string.
 * @n_buffer: Number of characters in @buffer.
 * @digits: A pointer to the digits we're reading from. If count
 * is non-NULL, this is unused.
 * @n_digits: The number of digits in the string, in which we want
 * to put the grouping chars.
 * @min_width: The minimum width of the digits in the output string.
 * Output will be zero-padded on the left to fill.
 * @grouping: see definition in localeconv().
 * @thousands_sep: see definition in localeconv().
 *
 * There are 2 modes: counting and filling. If @buffer is NULL,
 * we are in counting mode, else filling mode.
 * If counting, the required buffer size is returned.
 * If filling, we know the buffer will be large enough, so we don't
 * need to pass in the buffer size.
 * Inserts thousand grouping characters (as defined by grouping and
 * thousands_sep) into the string between buffer and buffer+n_digits.
 *
 * Return value: 0 on error, else 1. Note that no error can occur if
 * count is non-NULL.
 *
 * This name won't be used, the includer of this file should define
 * it to be the actual function name, based on unicode or string.
 *
 * As closely as possible, this code mimics the logic in decimal.py's
 _insert_thousands_sep().
 **/
Py_ssize_t
_Py_InsertThousandsGrouping(STRINGLIB_CHAR*buffer,
Py_ssize_tn_buffer,
STRINGLIB_CHAR*digits,
Py_ssize_tn_digits,
Py_ssize_tmin_width,
constchar*grouping,
constchar*thousands_sep)
{
Py_ssize_tcount=0;
Py_ssize_tn_zeros;
intloop_broken=0;
intuse_separator=0; /* First time through, don't append the
 separator. They only go between
 groups. */
STRINGLIB_CHAR*buffer_end=NULL;
STRINGLIB_CHAR*digits_end=NULL;
Py_ssize_tl;
Py_ssize_tn_chars;
Py_ssize_tthousands_sep_len=strlen(thousands_sep);
Py_ssize_tremaining=n_digits; /* Number of chars remaining to
 be looked at */
/* A generator that returns all of the grouping widths, until it
 returns 0. */
GroupGeneratorgroupgen;
_GroupGenerator_init(&groupgen, grouping);

if (buffer) {
buffer_end=buffer+n_buffer;
digits_end=digits+n_digits;
 }

while ((l=_GroupGenerator_next(&groupgen)) >0) {
l=MIN(l, MAX(MAX(remaining, min_width), 1));
n_zeros=MAX(0, l-remaining);
n_chars=MAX(0, MIN(remaining, l));

/* Use n_zero zero's and n_chars chars */

/* Count only, don't do anything. */
count+= (use_separator ? thousands_sep_len : 0) +n_zeros+n_chars;

if (buffer) {
/* Copy into the output buffer. */
fill(&digits_end, &buffer_end, n_chars, n_zeros,
use_separator ? thousands_sep : NULL, thousands_sep_len);
 }

/* Use a separator next time. */
use_separator=1;

remaining-=n_chars;
min_width-=l;

if (remaining <= 0&&min_width <= 0) {
loop_broken=1;
break;
 }
min_width-=thousands_sep_len;
 }
if (!loop_broken) {
/* We left the loop without using a break statement. */

l=MAX(MAX(remaining, min_width), 1);
n_zeros=MAX(0, l-remaining);
n_chars=MAX(0, MIN(remaining, l));

/* Use n_zero zero's and n_chars chars */
count+= (use_separator ? thousands_sep_len : 0) +n_zeros+n_chars;
if (buffer) {
/* Copy into the output buffer. */
fill(&digits_end, &buffer_end, n_chars, n_zeros,
use_separator ? thousands_sep : NULL, thousands_sep_len);
 }
 }
returncount;
}

/**
 * _Py_InsertThousandsGroupingLocale:
 * @buffer: A pointer to the start of a string.
 * @n_digits: The number of digits in the string, in which we want
 * to put the grouping chars.
 *
 * Reads thee current locale and calls _Py_InsertThousandsGrouping().
 **/
Py_ssize_t
_Py_InsertThousandsGroupingLocale(STRINGLIB_CHAR*buffer,
Py_ssize_tn_buffer,
STRINGLIB_CHAR*digits,
Py_ssize_tn_digits,
Py_ssize_tmin_width)
{
structlconv*locale_data=localeconv();
constchar*grouping=locale_data->grouping;
constchar*thousands_sep=locale_data->thousands_sep;

return_Py_InsertThousandsGrouping(buffer, n_buffer, digits, n_digits,
min_width, grouping, thousands_sep);
}
#endif/* STRINGLIB_LOCALEUTIL_H */