/* Conversion UCS-4 to UTF-8. Copyright (C) 2002, 2006-2007, 2009-2018 Free Software Foundation, Inc. Written by Bruno Haible , 2002. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . */ #include /* Specification. */ #include "unistr.h" #ifndef FALLTHROUGH # if __GNUC__ < 7 # define FALLTHROUGH ((void) 0) # else # define FALLTHROUGH __attribute__ ((__fallthrough__)) # endif #endif int u8_uctomb_aux (uint8_t *s, ucs4_t uc, int n) { int count; if (uc < 0x80) /* The case n >= 1 is already handled by the caller. */ return -2; else if (uc < 0x800) count = 2; else if (uc < 0x10000) { if (uc < 0xd800 || uc >= 0xe000) count = 3; else return -1; } else if (uc < 0x110000) count = 4; else return -1; if (n < count) return -2; switch (count) /* note: code falls through cases! */ { case 4: s[3] = 0x80 | (uc & 0x3f); uc = uc >> 6; uc |= 0x10000; FALLTHROUGH; case 3: s[2] = 0x80 | (uc & 0x3f); uc = uc >> 6; uc |= 0x800; FALLTHROUGH; case 2: s[1] = 0x80 | (uc & 0x3f); uc = uc >> 6; uc |= 0xc0; /*case 1:*/ s[0] = uc; } return count; }