1 /* Arabic joining group of Unicode characters. 2 Copyright (C) 2011-2021 Free Software Foundation, Inc. 3 Written by Bruno Haible <bruno@clisp.org>, 2011. 4 5 This file is free software. 6 It is dual-licensed under "the GNU LGPLv3+ or the GNU GPLv2+". 7 You can redistribute it and/or modify it under either 8 - the terms of the GNU Lesser General Public License as published 9 by the Free Software Foundation; either version 3, or (at your 10 option) any later version, or 11 - the terms of the GNU General Public License as published by the 12 Free Software Foundation; either version 2, or (at your option) 13 any later version, or 14 - the same dual license "the GNU LGPLv3+ or the GNU GPLv2+". 15 16 This file is distributed in the hope that it will be useful, 17 but WITHOUT ANY WARRANTY; without even the implied warranty of 18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 19 Lesser General Public License and the GNU General Public License 20 for more details. 21 22 You should have received a copy of the GNU Lesser General Public 23 License and of the GNU General Public License along with this 24 program. If not, see <https://www.gnu.org/licenses/>. */ 25 26 #include <config.h> 27 28 /* Specification. */ 29 #include "unictype.h" 30 31 /* Define u_joining_group table. */ 32 #include "joininggroup_of.h" 33 34 int 35 uc_joining_group (ucs4_t uc) /* */ 36 { 37 unsigned int index1 = uc >> joining_group_header_0; 38 if (index1 < joining_group_header_1) 39 { 40 int lookup1 = u_joining_group.level1[index1]; 41 if (lookup1 >= 0) 42 { 43 unsigned int index2 = (uc >> joining_group_header_2) & joining_group_header_3; 44 int lookup2 = u_joining_group.level2[lookup1 + index2]; 45 if (lookup2 >= 0) 46 { 47 unsigned int index3 = ((uc & joining_group_header_4) + lookup2) * 7; 48 /* level3 contains 7-bit values, packed into 16-bit words. */ 49 unsigned int lookup3 = 50 (((unsigned int) u_joining_group.level3[index3>>4] 51 | ((unsigned int) u_joining_group.level3[(index3>>4)+1] << 16)) 52 >> (index3 % 16)) 53 & 0x7f; 54 55 return lookup3; 56 } 57 } 58 } 59 return UC_JOINING_GROUP_NONE; 60 }