Alexandre Lision | 8af73cb | 2013-12-10 14:11:20 -0500 | [diff] [blame] | 1 | /* $Id$ */ |
| 2 | /* |
| 3 | * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com) |
| 4 | * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 | */ |
| 20 | #include <pj/guid.h> |
| 21 | #include <pj/assert.h> |
| 22 | #include <pj/rand.h> |
| 23 | #include <pj/os.h> |
| 24 | #include <pj/string.h> |
| 25 | |
| 26 | PJ_DEF_DATA(const unsigned) PJ_GUID_STRING_LENGTH=32; |
| 27 | |
| 28 | static char guid_chars[64]; |
| 29 | |
| 30 | PJ_DEF(unsigned) pj_GUID_STRING_LENGTH() |
| 31 | { |
| 32 | return PJ_GUID_STRING_LENGTH; |
| 33 | } |
| 34 | |
| 35 | static void init_guid_chars(void) |
| 36 | { |
| 37 | char *p = guid_chars; |
| 38 | unsigned i; |
| 39 | |
| 40 | for (i=0; i<10; ++i) |
| 41 | *p++ = '0'+i; |
| 42 | |
| 43 | for (i=0; i<26; ++i) { |
| 44 | *p++ = 'a'+i; |
| 45 | *p++ = 'A'+i; |
| 46 | } |
| 47 | |
| 48 | *p++ = '-'; |
| 49 | *p++ = '.'; |
| 50 | } |
| 51 | |
| 52 | PJ_DEF(pj_str_t*) pj_generate_unique_string(pj_str_t *str) |
| 53 | { |
| 54 | char *p, *end; |
| 55 | |
| 56 | PJ_CHECK_STACK(); |
| 57 | |
| 58 | if (guid_chars[0] == '\0') { |
| 59 | pj_enter_critical_section(); |
| 60 | if (guid_chars[0] == '\0') { |
| 61 | init_guid_chars(); |
| 62 | } |
| 63 | pj_leave_critical_section(); |
| 64 | } |
| 65 | |
| 66 | /* This would only work if PJ_GUID_STRING_LENGTH is multiple of 2 bytes */ |
| 67 | pj_assert(PJ_GUID_STRING_LENGTH % 2 == 0); |
| 68 | |
| 69 | for (p=str->ptr, end=p+PJ_GUID_STRING_LENGTH; p<end; ) { |
| 70 | pj_uint32_t rand_val = pj_rand(); |
| 71 | pj_uint32_t rand_idx = RAND_MAX; |
| 72 | |
| 73 | for ( ; rand_idx>0 && p<end; rand_idx>>=8, rand_val>>=8, p++) { |
| 74 | *p = guid_chars[(rand_val & 0xFF) & 63]; |
| 75 | } |
| 76 | } |
| 77 | |
| 78 | str->slen = PJ_GUID_STRING_LENGTH; |
| 79 | return str; |
| 80 | } |
| 81 | |