| /* $Id$ */ |
| /* |
| * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com) |
| * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org> |
| * |
| * 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 2 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, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| #include <pj/guid.h> |
| #include <pj/assert.h> |
| #include <pj/rand.h> |
| #include <pj/os.h> |
| #include <pj/string.h> |
| |
| PJ_DEF_DATA(const unsigned) PJ_GUID_STRING_LENGTH=32; |
| |
| static char guid_chars[64]; |
| |
| PJ_DEF(unsigned) pj_GUID_STRING_LENGTH() |
| { |
| return PJ_GUID_STRING_LENGTH; |
| } |
| |
| static void init_guid_chars(void) |
| { |
| char *p = guid_chars; |
| unsigned i; |
| |
| for (i=0; i<10; ++i) |
| *p++ = '0'+i; |
| |
| for (i=0; i<26; ++i) { |
| *p++ = 'a'+i; |
| *p++ = 'A'+i; |
| } |
| |
| *p++ = '-'; |
| *p++ = '.'; |
| } |
| |
| PJ_DEF(pj_str_t*) pj_generate_unique_string(pj_str_t *str) |
| { |
| char *p, *end; |
| |
| PJ_CHECK_STACK(); |
| |
| if (guid_chars[0] == '\0') { |
| pj_enter_critical_section(); |
| if (guid_chars[0] == '\0') { |
| init_guid_chars(); |
| } |
| pj_leave_critical_section(); |
| } |
| |
| /* This would only work if PJ_GUID_STRING_LENGTH is multiple of 2 bytes */ |
| pj_assert(PJ_GUID_STRING_LENGTH % 2 == 0); |
| |
| for (p=str->ptr, end=p+PJ_GUID_STRING_LENGTH; p<end; ) { |
| pj_uint32_t rand_val = pj_rand(); |
| pj_uint32_t rand_idx = RAND_MAX; |
| |
| for ( ; rand_idx>0 && p<end; rand_idx>>=8, rand_val>>=8, p++) { |
| *p = guid_chars[(rand_val & 0xFF) & 63]; |
| } |
| } |
| |
| str->slen = PJ_GUID_STRING_LENGTH; |
| return str; |
| } |
| |