1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
/* EINA - EFL data type library
* Copyright (C) 2002-2008 Carsten Haitzler, Jorge Luis Zapata Muga, Cedric Bail
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library;
* if not, see <http://www.gnu.org/licenses/>.
*
* This file incorporates work covered by the following copyright and
* permission notice:
*
* Copyright (C) 2008 Peter Wehrfritz
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies of the Software and its Copyright notices. In addition publicly
* documented acknowledgment must be given that this software has been used if no
* source code of this software is made available publicly. This includes
* acknowledgments in either Copyright notices, Manuals, Publicity and Marketing
* documents or any documentation provided with any product containing this
* software. This License does not apply to any software that links to the
* libraries provided by this software (statically or dynamically), but only to
* the software provided.
*
* Please see the OLD-COPYING.PLAIN for a plain-english explanation of this notice
* and it's intent.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#ifndef EINA_USTRINGSHARE_H_
#define EINA_USTRINGSHARE_H_
#include "eina_types.h"
#include "eina_unicode.h"
/**
* @addtogroup Eina_UStringshare_Group Unicode Stringshare
*
* These functions allow you to store one copy of a string, and use it
* throughout your program.
*
* This is a method to reduce the number of duplicated strings kept in
* memory. It's pretty common for the same strings to be dynamically
* allocated repeatedly between applications and libraries, especially in
* circumstances where you could have multiple copies of a structure that
* allocates the string. So rather than duplicating and freeing these
* strings, you request a read-only pointer to an existing string and
* only incur the overhead of a hash lookup.
*
* It sounds like micro-optimizing, but profiling has shown this can have
* a significant impact as you scale the number of copies up. It improves
* string creation/destruction speed, reduces memory use and decreases
* memory fragmentation, so a win all-around.
*
* For more information, you can look at the @ref tutorial_ustringshare_page.
*/
/**
* @addtogroup Eina_Data_Types_Group Data Types
*
* @{
*/
/**
* @defgroup Eina_UStringshare_Group Unicode Stringshare
*
* @{
*/
/**
* @brief Retrieve an instance of a string for use in a program.
*
* @param str The string to retrieve an instance of.
* @param slen The string size (<= strlen(str)).
* @return A pointer to an instance of the string on success.
* @c NULL on failure.
*
* This function retrieves an instance of @p str. If @p str is
* @c NULL, then @c NULL is returned. If @p str is already stored, it
* is just returned and its reference counter is increased. Otherwise
* it is added to the strings to be searched and a duplicated string
* of @p str is returned.
*
* This function does not check string size, but uses the
* exact given size. This can be used to share_common part of a larger
* buffer or substring.
*
* @see eina_ustringshare_add()
*/
EAPI const Eina_Unicode *eina_ustringshare_add_length(const Eina_Unicode *str, unsigned int slen) EINA_WARN_UNUSED_RESULT;
/**
* @brief Retrieve an instance of a string for use in a program.
*
* @param str The NULL-terminated string to retrieve an instance of.
* @return A pointer to an instance of the string on success.
* @c NULL on failure.
*
* This function retrieves an instance of @p str. If @p str is
* @c NULL, then @c NULL is returned. If @p str is already stored, it
* is just returned and its reference counter is increased. Otherwise
* it is added to the strings to be searched and a duplicated string
* of @p str is returned.
*
* The string @p str must be NULL-terminated ('@\0') and its full
* length will be used. To use part of the string or non-null
* terminated, use eina_stringshare_add_length() instead.
*
* @see eina_ustringshare_add_length()
*/
EAPI const Eina_Unicode *eina_ustringshare_add(const Eina_Unicode *str) EINA_WARN_UNUSED_RESULT;
/**
* Increment references of the given shared string.
*
* @param str The shared string.
* @return A pointer to an instance of the string on success.
* @c NULL on failure.
*
* This is similar to eina_share_common_add(), but it's faster since it will
* avoid lookups if possible, but on the down side it requires the parameter
* to be shared before, in other words, it must be the return of a previous
* eina_ustringshare_add().
*
* There is no unref since this is the work of eina_ustringshare_del().
*/
EAPI const Eina_Unicode *eina_ustringshare_ref(const Eina_Unicode *str);
/**
* @brief Note that the given string has lost an instance.
*
* @param str string The given string.
*
* This function decreases the reference counter associated to @p str
* if it exists. If that counter reaches 0, the memory associated to
* @p str is freed. If @p str is @c NULL, the function returns
* immediately.
*
* Note that if the given pointer is not shared or @c NULL, bad things
* will happen, likely a segmentation fault.
*/
EAPI void eina_ustringshare_del(const Eina_Unicode *str);
/**
* @brief Note that the given string @b must be shared.
*
* @param str the shared string to know the length. It is safe to
* give @c NULL, in that case @c -1 is returned.
*
* This function is a cheap way to known the length of a shared
* string. Note that if the given pointer is not shared, bad
* things will happen, likely a segmentation fault. If in doubt, try
* strlen().
*/
EAPI int eina_ustringshare_strlen(const Eina_Unicode *str) EINA_PURE EINA_WARN_UNUSED_RESULT;
/**
* @brief Dump the contents of the share_common.
*
* This function dumps all strings in the share_common to stdout with a
* DDD: prefix per line and a memory usage summary.
*/
EAPI void eina_ustringshare_dump(void);
static inline Eina_Bool eina_ustringshare_replace(const Eina_Unicode **p_str, const Eina_Unicode *news) EINA_ARG_NONNULL(1);
static inline Eina_Bool eina_ustringshare_replace_length(const Eina_Unicode **p_str, const Eina_Unicode *news, unsigned int slen) EINA_ARG_NONNULL(1);
#include "eina_inline_ustringshare.x"
/**
* @}
*/
/**
* @}
*/
#endif /* EINA_STRINGSHARE_H_ */
|
