/* Internal header for proving correct grouping in strings of numbers. Copyright (C) 1995,1996,1997,1998,2000,2003 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995. 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, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ #include <limits.h> #include <stddef.h> #include <string.h> #ifndef MAX #define MAX(a,b) ({ typeof(a) _a = (a); typeof(b) _b = (b); \ _a > _b ? _a : _b; }) #endif #ifdef USE_WIDE_CHAR # include <wctype.h> # define L_(Ch) L##Ch # define UCHAR_TYPE wint_t # define STRING_TYPE wchar_t #else # define L_(Ch) Ch # define UCHAR_TYPE unsigned char # define STRING_TYPE char #endif #include "grouping.h" /* Find the maximum prefix of the string between BEGIN and END which satisfies the grouping rules. It is assumed that at least one digit follows BEGIN directly. */ const STRING_TYPE * #ifdef USE_WIDE_CHAR __correctly_grouped_prefixwc (const STRING_TYPE *begin, const STRING_TYPE *end, wchar_t thousands, #else __correctly_grouped_prefixmb (const STRING_TYPE *begin, const STRING_TYPE *end, const char *thousands, #endif const char *grouping) { #ifndef USE_WIDE_CHAR size_t thousands_len; int cnt; #endif if (grouping == NULL) return end; #ifndef USE_WIDE_CHAR thousands_len = strlen (thousands); #endif while (end > begin) { const STRING_TYPE *cp = end - 1; const char *gp = grouping; /* Check first group. */ while (cp >= begin) { #ifdef USE_WIDE_CHAR if (*cp == thousands) break; #else if (cp[thousands_len - 1] == *thousands) { for (cnt = 1; thousands[cnt] != '\0'; ++cnt) if (thousands[cnt] != cp[thousands_len - 1 - cnt]) break; if (thousands[cnt] == '\0') break; } #endif --cp; } /* We allow the representation to contain no grouping at all even if the locale specifies we can have grouping. */ if (cp < begin) return end; if (end - cp == (int) *gp + 1) { /* This group matches the specification. */ const STRING_TYPE *new_end; if (cp < begin) /* There is just one complete group. We are done. */ return end; /* CP points to a thousands separator character. The preceding remainder of the string from BEGIN to NEW_END is the part we will consider if there is a grouping error in this trailing portion from CP to END. */ new_end = cp - 1; /* Loop while the grouping is correct. */ while (1) { /* Get the next grouping rule. */ ++gp; if (*gp == 0) /* If end is reached use last rule. */ --gp; /* Skip the thousands separator. */ --cp; if (*gp == CHAR_MAX #if CHAR_MIN < 0 || *gp < 0 #endif ) { /* No more thousands separators are allowed to follow. */ while (cp >= begin) { #ifdef USE_WIDE_CHAR if (*cp == thousands) break; #else for (cnt = 0; thousands[cnt] != '\0'; ++cnt) if (thousands[cnt] != cp[thousands_len - cnt - 1]) break; if (thousands[cnt] == '\0') break; #endif --cp; } if (cp < begin) /* OK, only digits followed. */ return end; } else { /* Check the next group. */ const STRING_TYPE *group_end = cp; while (cp >= begin) { #ifdef USE_WIDE_CHAR if (*cp == thousands) break; #else for (cnt = 0; thousands[cnt] != '\0'; ++cnt) if (thousands[cnt] != cp[thousands_len - cnt - 1]) break; if (thousands[cnt] == '\0') break; #endif --cp; } if (cp < begin && group_end - cp <= (int) *gp) /* Final group is correct. */ return end; if (cp < begin || group_end - cp != (int) *gp) /* Incorrect group. Punt. */ break; } } /* The trailing portion of the string starting at NEW_END contains a grouping error. So we will look for a correctly grouped number in the preceding portion instead. */ end = new_end; } else { /* Even the first group was wrong; determine maximum shift. */ if (end - cp > (int) *gp + 1) end = cp + (int) *gp + 1; else if (cp < begin) /* This number does not fill the first group, but is correct. */ return end; else /* CP points to a thousands separator character. */ end = cp; } } return MAX (begin, end); }