comparison: libpurple/stringref.c
libpurple/stringref.c
- changeset 16238
- 33bf2fd32108
- parent 8072
- 32392daf7a95
- parent 15884
- 4de1981757fc
equal
deleted
inserted
replaced
| 13071:b98e72d4089a | 16238:33bf2fd32108 |
|---|---|
| 1 /** | |
| 2 * @file stringref.c Reference-counted immutable strings | |
| 3 * @ingroup core | |
| 4 * | |
| 5 * purple | |
| 6 * | |
| 7 * Purple is the legal property of its developers, whose names are too numerous | |
| 8 * to list here. Please refer to the COPYRIGHT file distributed with this | |
| 9 * source distribution. | |
| 10 * | |
| 11 * This program is free software; you can redistribute it and/or modify | |
| 12 * it under the terms of the GNU General Public License as published by | |
| 13 * the Free Software Foundation; either version 2 of the License, or | |
| 14 * (at your option) any later version. | |
| 15 * | |
| 16 * This program 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 | |
| 19 * GNU General Public License for more details. | |
| 20 * | |
| 21 * You should have received a copy of the GNU General Public License | |
| 22 * along with this program; if not, write to the Free Software | |
| 23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
| 24 * | |
| 25 */ | |
| 26 | |
| 27 #include "internal.h" | |
| 28 | |
| 29 #include <string.h> | |
| 30 #include <stdarg.h> | |
| 31 | |
| 32 #include "debug.h" | |
| 33 #include "stringref.h" | |
| 34 | |
| 35 /** | |
| 36 * The internal representation of a stringref. | |
| 37 * | |
| 38 * @note For this structure to be useful, the string contained within | |
| 39 * it must be immutable -- for this reason, do _not_ access it | |
| 40 * directly! | |
| 41 */ | |
| 42 struct _PurpleStringref { | |
| 43 guint32 ref; /**< The reference count of this string. | |
| 44 * Note that reference counts are only | |
| 45 * 31 bits, and the high-order bit | |
| 46 * indicates whether this string is up | |
| 47 * for GC at the next idle handler... | |
| 48 * But you aren't going to touch this | |
| 49 * anyway, right? */ | |
| 50 char value[1]; /**< The string contained in this ref. | |
| 51 * Notice that it is simply "hanging | |
| 52 * off the end" of the ref ... this | |
| 53 * is to save an allocation. */ | |
| 54 }; | |
| 55 | |
| 56 #define REFCOUNT(x) ((x) & 0x7fffffff) | |
| 57 | |
| 58 static GList *gclist = NULL; | |
| 59 | |
| 60 static void stringref_free(PurpleStringref *stringref); | |
| 61 static gboolean gs_idle_cb(gpointer data); | |
| 62 | |
| 63 PurpleStringref *purple_stringref_new(const char *value) | |
| 64 { | |
| 65 PurpleStringref *newref; | |
| 66 | |
| 67 if (value == NULL) | |
| 68 return NULL; | |
| 69 | |
| 70 newref = g_malloc(sizeof(PurpleStringref) + strlen(value)); | |
| 71 strcpy(newref->value, value); | |
| 72 newref->ref = 1; | |
| 73 | |
| 74 return newref; | |
| 75 } | |
| 76 | |
| 77 PurpleStringref *purple_stringref_new_noref(const char *value) | |
| 78 { | |
| 79 PurpleStringref *newref; | |
| 80 | |
| 81 if (value == NULL) | |
| 82 return NULL; | |
| 83 | |
| 84 newref = g_malloc(sizeof(PurpleStringref) + strlen(value)); | |
| 85 strcpy(newref->value, value); | |
| 86 newref->ref = 0x80000000; | |
| 87 | |
| 88 if (gclist == NULL) | |
| 89 g_idle_add(gs_idle_cb, NULL); | |
| 90 gclist = g_list_prepend(gclist, newref); | |
| 91 | |
| 92 return newref; | |
| 93 } | |
| 94 | |
| 95 PurpleStringref *purple_stringref_printf(const char *format, ...) | |
| 96 { | |
| 97 PurpleStringref *newref; | |
| 98 va_list ap; | |
| 99 | |
| 100 if (format == NULL) | |
| 101 return NULL; | |
| 102 | |
| 103 va_start(ap, format); | |
| 104 newref = g_malloc(sizeof(PurpleStringref) + g_printf_string_upper_bound(format, ap)); | |
| 105 vsprintf(newref->value, format, ap); | |
| 106 va_end(ap); | |
| 107 newref->ref = 1; | |
| 108 | |
| 109 return newref; | |
| 110 } | |
| 111 | |
| 112 PurpleStringref *purple_stringref_ref(PurpleStringref *stringref) | |
| 113 { | |
| 114 if (stringref == NULL) | |
| 115 return NULL; | |
| 116 stringref->ref++; | |
| 117 return stringref; | |
| 118 } | |
| 119 | |
| 120 void purple_stringref_unref(PurpleStringref *stringref) | |
| 121 { | |
| 122 if (stringref == NULL) | |
| 123 return; | |
| 124 if (REFCOUNT(--(stringref->ref)) == 0) { | |
| 125 if (stringref->ref & 0x80000000) | |
| 126 gclist = g_list_remove(gclist, stringref); | |
| 127 stringref_free(stringref); | |
| 128 } | |
| 129 } | |
| 130 | |
| 131 const char *purple_stringref_value(const PurpleStringref *stringref) | |
| 132 { | |
| 133 return (stringref == NULL ? NULL : stringref->value); | |
| 134 } | |
| 135 | |
| 136 int purple_stringref_cmp(const PurpleStringref *s1, const PurpleStringref *s2) | |
| 137 { | |
| 138 return (s1 == s2 ? 0 : strcmp(purple_stringref_value(s1), purple_stringref_value(s2))); | |
| 139 } | |
| 140 | |
| 141 size_t purple_stringref_len(const PurpleStringref *stringref) | |
| 142 { | |
| 143 return strlen(purple_stringref_value(stringref)); | |
| 144 } | |
| 145 | |
| 146 static void stringref_free(PurpleStringref *stringref) | |
| 147 { | |
| 148 #ifdef DEBUG | |
| 149 if (REFCOUNT(stringref->ref) != 0) { | |
| 150 purple_debug(PURPLE_DEBUG_ERROR, "stringref", "Free of nonzero (%d) ref stringref!\n", REFCOUNT(stringref->ref)); | |
| 151 return; | |
| 152 } | |
| 153 #endif /* DEBUG */ | |
| 154 g_free(stringref); | |
| 155 } | |
| 156 | |
| 157 static gboolean gs_idle_cb(gpointer data) | |
| 158 { | |
| 159 PurpleStringref *ref; | |
| 160 GList *del; | |
| 161 | |
| 162 while (gclist != NULL) { | |
| 163 ref = gclist->data; | |
| 164 if (REFCOUNT(ref->ref) == 0) { | |
| 165 stringref_free(ref); | |
| 166 } | |
| 167 del = gclist; | |
| 168 gclist = gclist->next; | |
| 169 g_list_free_1(del); | |
| 170 } | |
| 171 | |
| 172 return FALSE; | |
| 173 } |
