1/* vi: set sw=4 ts=4: */ 2/* 3 * Utility routines. 4 * 5 * Copyright (C) Manuel Nova III <mnovoa3@bellsouth.net> 6 * and Vladimir Oleynik <vodz@usa.net> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 21 * 22 * 23 */ 24 25#include <stdio.h> 26#include <limits.h> 27#include "libbb.h" 28 29 30 31char process_escape_sequence(const char **ptr) 32{ 33 static const char charmap[] = { 34 'a', 'b', 'f', 'n', 'r', 't', 'v', '\\', 0, 35 '\a', '\b', '\f', '\n', '\r', '\t', '\v', '\\', '\\' }; 36 37 const char *p; 38 const char *q; 39 int num_digits; 40 unsigned int n; 41 42 n = 0; 43 q = *ptr; 44 45 for ( num_digits = 0 ; num_digits < 3 ; ++num_digits) { 46 if ((*q < '0') || (*q > '7')) { /* not a digit? */ 47 break; 48 } 49 n = n * 8 + (*q++ - '0'); 50 } 51 52 if (num_digits == 0) { /* mnemonic escape sequence? */ 53 for (p=charmap ; *p ; p++) { 54 if (*p == *q) { 55 q++; 56 break; 57 } 58 } 59 n = *(p+(sizeof(charmap)/2)); 60 } 61 62 /* doesn't hurt to fall through to here from mnemonic case */ 63 if (n > UCHAR_MAX) { /* is octal code too big for a char? */ 64 n /= 8; /* adjust value and */ 65 --q; /* back up one char */ 66 } 67 68 *ptr = q; 69 return (char) n; 70} 71 72 73/* END CODE */ 74/* 75Local Variables: 76c-file-style: "linux" 77c-basic-offset: 4 78tab-width: 4 79End: 80*/ 81