/Objects/stringlib/localeutil.h
http://unladen-swallow.googlecode.com/ · C Header · 130 lines · 65 code · 13 blank · 52 comment · 15 complexity · 1d87a92ba0baf6c9d21ba00b17fe9f24 MD5 · raw file
- /* stringlib: locale related helpers implementation */
- #ifndef STRINGLIB_LOCALEUTIL_H
- #define STRINGLIB_LOCALEUTIL_H
- #include <locale.h>
- /**
- * _Py_InsertThousandsGrouping:
- * @buffer: A pointer to the start of a string.
- * @n_buffer: The length of the string.
- * @n_digits: The number of digits in the string, in which we want
- * to put the grouping chars.
- * @buf_size: The maximum size of the buffer pointed to by buffer.
- * @count: If non-NULL, points to a variable that will receive the
- * number of characters we need to insert (and no formatting
- * will actually occur).
- * @append_zero_char: If non-zero, put a trailing zero at the end of
- * of the resulting string, if and only if we modified the
- * string.
- *
- * Inserts thousand grouping characters (as defined in the current
- * locale) into the string between buffer and buffer+n_digits. If
- * count is non-NULL, don't do any formatting, just count the number
- * of characters to insert. This is used by the caller to
- * appropriately resize the buffer, if needed. If count is non-NULL,
- * buffer can be NULL (it is not dereferenced at all in that case).
- *
- * 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.
- **/
- int
- _Py_InsertThousandsGrouping(STRINGLIB_CHAR *buffer,
- Py_ssize_t n_buffer,
- Py_ssize_t n_digits,
- Py_ssize_t buf_size,
- Py_ssize_t *count,
- int append_zero_char)
- {
- struct lconv *locale_data = localeconv();
- const char *grouping = locale_data->grouping;
- const char *thousands_sep = locale_data->thousands_sep;
- Py_ssize_t thousands_sep_len = strlen(thousands_sep);
- STRINGLIB_CHAR *pend = NULL; /* current end of buffer */
- STRINGLIB_CHAR *pmax = NULL; /* max of buffer */
- char current_grouping;
- Py_ssize_t remaining = n_digits; /* Number of chars remaining to
- be looked at */
- /* Initialize the character count, if we're just counting. */
- if (count)
- *count = 0;
- else {
- /* We're not just counting, we're modifying buffer */
- pend = buffer + n_buffer;
- pmax = buffer + buf_size;
- }
- /* Starting at the end and working right-to-left, keep track of
- what grouping needs to be added and insert that. */
- current_grouping = *grouping++;
- /* If the first character is 0, perform no grouping at all. */
- if (current_grouping == 0)
- return 1;
- while (remaining > current_grouping) {
- /* Always leave buffer and pend valid at the end of this
- loop, since we might leave with a return statement. */
- remaining -= current_grouping;
- if (count) {
- /* We're only counting, not touching the memory. */
- *count += thousands_sep_len;
- }
- else {
- /* Do the formatting. */
- STRINGLIB_CHAR *plast = buffer + remaining;
- /* Is there room to insert thousands_sep_len chars? */
- if (pmax - pend < thousands_sep_len)
- /* No room. */
- return 0;
- /* Move the rest of the string down. */
- memmove(plast + thousands_sep_len,
- plast,
- (pend - plast) * sizeof(STRINGLIB_CHAR));
- /* Copy the thousands_sep chars into the buffer. */
- #if STRINGLIB_IS_UNICODE
- /* Convert from the char's of the thousands_sep from
- the locale into unicode. */
- {
- Py_ssize_t i;
- for (i = 0; i < thousands_sep_len; ++i)
- plast[i] = thousands_sep[i];
- }
- #else
- /* No conversion, just memcpy the thousands_sep. */
- memcpy(plast, thousands_sep, thousands_sep_len);
- #endif
- }
- /* Adjust end pointer. */
- pend += thousands_sep_len;
- /* Move to the next grouping character, unless we're
- repeating (which is designated by a grouping of 0). */
- if (*grouping != 0) {
- current_grouping = *grouping++;
- if (current_grouping == CHAR_MAX)
- /* We're done. */
- break;
- }
- }
- if (append_zero_char) {
- /* Append a zero character to mark the end of the string,
- if there's room. */
- if (pend - (buffer + remaining) < 1)
- /* No room, error. */
- return 0;
- *pend = 0;
- }
- return 1;
- }
- #endif /* STRINGLIB_LOCALEUTIL_H */