AppPkg/Applications/Python/Python-2.7.10/PyMod-2.7.10/Objects/stringlib/localeutil.h

   1 /** @file
   2     stringlib: locale related helpers implementation.
   3
   4     Copyright (c) 2011, Intel Corporation. All rights reserved.<BR>
   5     This program and the accompanying materials are licensed and made available under
   6     the terms and conditions of the BSD License that accompanies this distribution.
   7     The full text of the license may be found at
   8     http://opensource.org/licenses/bsd-license.
   9
  10     THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11     WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12 **/
  13
  14 #ifndef STRINGLIB_LOCALEUTIL_H
  15 #define STRINGLIB_LOCALEUTIL_H
  16
  17 #include <locale.h>
  18
  19 // Prevent conflicts with EFI
  20 #undef  MAX
  21 #undef  MIN
  22
  23 #define MAX(x, y) ((x) < (y) ? (y) : (x))
  24 #define MIN(x, y) ((x) < (y) ? (x) : (y))
  25
  26 typedef struct {
  27     const char *grouping;
  28     char previous;
  29     Py_ssize_t i; /* Where we're currently pointing in grouping. */
  30 } GroupGenerator;
  31
  32 static void
  33 _GroupGenerator_init(GroupGenerator *self, const char *grouping)
  34 {
  35     self->grouping = grouping;
  36     self->i = 0;
  37     self->previous = 0;
  38 }
  39
  40 /* Returns the next grouping, or 0 to signify end. */
  41 static Py_ssize_t
  42 _GroupGenerator_next(GroupGenerator *self)
  43 {
  44     /* Note that we don't really do much error checking here. If a
  45        grouping string contains just CHAR_MAX, for example, then just
  46        terminate the generator. That shouldn't happen, but at least we
  47        fail gracefully. */
  48     switch (self->grouping[self->i]) {
  49     case 0:
  50         return self->previous;
  51     case CHAR_MAX:
  52         /* Stop the generator. */
  53         return 0;
  54     default: {
  55         char ch = self->grouping[self->i];
  56         self->previous = ch;
  57         self->i++;
  58         return (Py_ssize_t)ch;
  59     }
  60     }
  61 }
  62
  63 /* Fill in some digits, leading zeros, and thousands separator. All
  64    are optional, depending on when we're called. */
  65 static void
  66 fill(STRINGLIB_CHAR **digits_end, STRINGLIB_CHAR **buffer_end,
  67      Py_ssize_t n_chars, Py_ssize_t n_zeros, const char* thousands_sep,
  68      Py_ssize_t thousands_sep_len)
  69 {
  70 #if STRINGLIB_IS_UNICODE
  71     Py_ssize_t i;
  72 #endif
  73
  74     if (thousands_sep) {
  75         *buffer_end -= thousands_sep_len;
  76
  77         /* Copy the thousands_sep chars into the buffer. */
  78 #if STRINGLIB_IS_UNICODE
  79         /* Convert from the char's of the thousands_sep from
  80            the locale into unicode. */
  81         for (i = 0; i < thousands_sep_len; ++i)
  82             (*buffer_end)[i] = thousands_sep[i];
  83 #else
  84         /* No conversion, just memcpy the thousands_sep. */
  85         memcpy(*buffer_end, thousands_sep, thousands_sep_len);
  86 #endif
  87     }
  88
  89     *buffer_end -= n_chars;
  90     *digits_end -= n_chars;
  91     memcpy(*buffer_end, *digits_end, n_chars * sizeof(STRINGLIB_CHAR));
  92
  93     *buffer_end -= n_zeros;
  94     STRINGLIB_FILL(*buffer_end, '0', n_zeros);
  95 }
  96
  97 /**
  98  * _Py_InsertThousandsGrouping:
  99  * @buffer: A pointer to the start of a string.
 100  * @n_buffer: Number of characters in @buffer.
 101  * @digits: A pointer to the digits we're reading from. If count
 102  *          is non-NULL, this is unused.
 103  * @n_digits: The number of digits in the string, in which we want
 104  *            to put the grouping chars.
 105  * @min_width: The minimum width of the digits in the output string.
 106  *             Output will be zero-padded on the left to fill.
 107  * @grouping: see definition in localeconv().
 108  * @thousands_sep: see definition in localeconv().
 109  *
 110  * There are 2 modes: counting and filling. If @buffer is NULL,
 111  *  we are in counting mode, else filling mode.
 112  * If counting, the required buffer size is returned.
 113  * If filling, we know the buffer will be large enough, so we don't
 114  *  need to pass in the buffer size.
 115  * Inserts thousand grouping characters (as defined by grouping and
 116  *  thousands_sep) into the string between buffer and buffer+n_digits.
 117  *
 118  * Return value: 0 on error, else 1.  Note that no error can occur if
 119  *  count is non-NULL.
 120  *
 121  * This name won't be used, the includer of this file should define
 122  *  it to be the actual function name, based on unicode or string.
 123  *
 124  * As closely as possible, this code mimics the logic in decimal.py's
 125     _insert_thousands_sep().
 126  **/
 127 Py_ssize_t
 128 _Py_InsertThousandsGrouping(STRINGLIB_CHAR *buffer,
 129                             Py_ssize_t n_buffer,
 130                             STRINGLIB_CHAR *digits,
 131                             Py_ssize_t n_digits,
 132                             Py_ssize_t min_width,
 133                             const char *grouping,
 134                             const char *thousands_sep)
 135 {
 136     Py_ssize_t count = 0;
 137     Py_ssize_t n_zeros;
 138     int loop_broken = 0;
 139     int use_separator = 0; /* First time through, don't append the
 140                               separator. They only go between
 141                               groups. */
 142     STRINGLIB_CHAR *buffer_end = NULL;
 143     STRINGLIB_CHAR *digits_end = NULL;
 144     Py_ssize_t l;
 145     Py_ssize_t n_chars;
 146     Py_ssize_t thousands_sep_len = strlen(thousands_sep);
 147     Py_ssize_t remaining = n_digits; /* Number of chars remaining to
 148                                         be looked at */
 149     /* A generator that returns all of the grouping widths, until it
 150        returns 0. */
 151     GroupGenerator groupgen;
 152     _GroupGenerator_init(&groupgen, grouping);
 153
 154     if (buffer) {
 155         buffer_end = buffer + n_buffer;
 156         digits_end = digits + n_digits;
 157     }
 158
 159     while ((l = _GroupGenerator_next(&groupgen)) > 0) {
 160         l = MIN(l, MAX(MAX(remaining, min_width), 1));
 161         n_zeros = MAX(0, l - remaining);
 162         n_chars = MAX(0, MIN(remaining, l));
 163
 164         /* Use n_zero zero's and n_chars chars */
 165
 166         /* Count only, don't do anything. */
 167         count += (use_separator ? thousands_sep_len : 0) + n_zeros + n_chars;
 168
 169         if (buffer) {
 170             /* Copy into the output buffer. */
 171             fill(&digits_end, &buffer_end, n_chars, n_zeros,
 172                  use_separator ? thousands_sep : NULL, thousands_sep_len);
 173         }
 174
 175         /* Use a separator next time. */
 176         use_separator = 1;
 177
 178         remaining -= n_chars;
 179         min_width -= l;
 180
 181         if (remaining <= 0 && min_width <= 0) {
 182             loop_broken = 1;
 183             break;
 184         }
 185         min_width -= thousands_sep_len;
 186     }
 187     if (!loop_broken) {
 188         /* We left the loop without using a break statement. */
 189
 190         l = MAX(MAX(remaining, min_width), 1);
 191         n_zeros = MAX(0, l - remaining);
 192         n_chars = MAX(0, MIN(remaining, l));
 193
 194         /* Use n_zero zero's and n_chars chars */
 195         count += (use_separator ? thousands_sep_len : 0) + n_zeros + n_chars;
 196         if (buffer) {
 197             /* Copy into the output buffer. */
 198             fill(&digits_end, &buffer_end, n_chars, n_zeros,
 199                  use_separator ? thousands_sep : NULL, thousands_sep_len);
 200         }
 201     }
 202     return count;
 203 }
 204
 205 /**
 206  * _Py_InsertThousandsGroupingLocale:
 207  * @buffer: A pointer to the start of a string.
 208  * @n_digits: The number of digits in the string, in which we want
 209  *            to put the grouping chars.
 210  *
 211  * Reads thee current locale and calls _Py_InsertThousandsGrouping().
 212  **/
 213 Py_ssize_t
 214 _Py_InsertThousandsGroupingLocale(STRINGLIB_CHAR *buffer,
 215                                   Py_ssize_t n_buffer,
 216                                   STRINGLIB_CHAR *digits,
 217                                   Py_ssize_t n_digits,
 218                                   Py_ssize_t min_width)
 219 {
 220         struct lconv *locale_data = localeconv();
 221         const char *grouping = locale_data->grouping;
 222         const char *thousands_sep = locale_data->thousands_sep;
 223
 224         return _Py_InsertThousandsGrouping(buffer, n_buffer, digits, n_digits,
 225                                            min_width, grouping, thousands_sep);
 226 }
 227 #endif /* STRINGLIB_LOCALEUTIL_H */