AppPkg/Applications/Python/PyMod-2.7.2/Objects/stringlib/localeutil.h

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