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/*
*
* This 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. This 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 this library; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/** @file
* Lexical analysis.
*/
#include "sys_string.h"
#include "lexis.h"
#include <errno.h>
/** Check if a value lies in a (closed) range.
*
* @param x value to test
* @param lo low end of the range
* @param hi high end of the range
* @return 1 if x is in the interval [lo, hi], 0 otherwise
*/
inline static int in_range(int x, int lo, int hi){
return (lo <= x) && (x <= hi);
}
/** Determine if a string is an (unsigned) decimal number.
*
* @param s pointer to characters to test
* @param n length of string
* @return 1 if s is a decimal number, 0 otherwise.
*/
int is_decimal_number(const char *s, int n){
int i;
if(n <= 0)return 0;
for(i = 0; i < n; i++){
if(!in_decimal_digit_class(s[i])) return 0;
}
return 1;
}
/** Determine if a string is a hex number.
* Hex numbers are 0, or start with 0x or 0X followed
* by a non-zero number of hex digits (0-9,a-f,A-F).
*
* @param s pointer to characters to test
* @param n length of string
* @return 1 if s is a hex number, 0 otherwise.
*/
int is_hex_number(const char *s, int n){
int i;
if(n <= 0) return 0;
if(n == 1){
return s[0]=='0';
}
if(n <= 3) return 0;
if(s[0] != '0' || (s[1] != 'x' && s[1] != 'X')) return 0;
for(i = 2; i < n; i++){
if(!in_hex_digit_class(s[i])) return 0;
}
return 1;
}
/** Test if a string matches a keyword.
* The comparison is case-insensitive.
* The comparison fails if either argument is null.
*
* @param s string
* @param k keyword
* @return 1 if they match, 0 otherwise
*/
int is_keyword(const char *s, const char *k){
return s && k && !strcasecmp(s, k);
}
/** Test if a string matches a character.
*
* @param s string
* @param c character (non-null)
* @return 1 if s contains exactly c, 0 otherwise
*/
int is_keychar(const char *s, char c){
return c && (s[0] == c) && !s[1];
}
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