1/* Copyright (C) 2009-2024 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <errno.h>
19#include <limits.h>
20#include <printf.h>
21#include <stdlib.h>
22#include <wchar.h>
23#include <libc-lock.h>
24
25
26struct printf_modifier_record
27{
28 struct printf_modifier_record *next;
29 int bit;
30 wchar_t str[0];
31};
32
33struct printf_modifier_record **__printf_modifier_table attribute_hidden;
34
35__libc_lock_define_initialized (static, lock)
36
37/* Bits to hand out. */
38static int next_bit;
39
40
41int
42__register_printf_modifier (const wchar_t *str)
43{
44 if (str[0] == L'\0')
45 {
46 einval:
47 __set_errno (EINVAL);
48 return -1;
49 }
50
51 const wchar_t *wc = str;
52 while (*wc != L'\0')
53 if (*wc < 0 || *wc > (wchar_t) UCHAR_MAX)
54 goto einval;
55 else
56 ++wc;
57
58 if (next_bit / 8 == sizeof (((struct printf_info *) NULL)->user))
59 {
60 __set_errno (ENOSPC);
61 return -1;
62 }
63
64 int result = -1;
65 __libc_lock_lock (lock);
66
67 if (__printf_modifier_table == NULL)
68 {
69 __printf_modifier_table = calloc (UCHAR_MAX,
70 size: sizeof (*__printf_modifier_table));
71 if (__printf_modifier_table == NULL)
72 goto out;
73 }
74
75 /* Create enough room for the string. But we don't need the first
76 character. */
77 struct printf_modifier_record *newp = malloc (size: sizeof (*newp)
78 + ((wc - str)
79 * sizeof (wchar_t)));
80 if (newp == NULL)
81 goto out;
82
83 newp->next = __printf_modifier_table[(unsigned char) *str];
84 newp->bit = 1 << next_bit++;
85 __wmemcpy (s1: newp->str, s2: str + 1, n: wc - str);
86
87 __printf_modifier_table[(unsigned char) *str] = newp;
88
89 result = newp->bit;
90
91 out:
92 __libc_lock_unlock (lock);
93
94 return result;
95}
96weak_alias (__register_printf_modifier, register_printf_modifier)
97
98
99#include <stdio.h>
100int
101attribute_hidden
102__handle_registered_modifier_mb (const unsigned char **format,
103 struct printf_info *info)
104{
105 struct printf_modifier_record *runp = __printf_modifier_table[**format];
106
107 int best_bit = 0;
108 int best_len = 0;
109 const unsigned char *best_cp = NULL;
110
111 while (runp != NULL)
112 {
113 const unsigned char *cp = *format + 1;
114 wchar_t *fcp = runp->str;
115
116 while (*cp != '\0' && *fcp != L'\0')
117 if (*cp != *fcp)
118 break;
119 else
120 ++cp, ++fcp;
121
122 if (*fcp == L'\0' && cp - *format > best_len)
123 {
124 best_cp = cp;
125 best_len = cp - *format;
126 best_bit = runp->bit;
127 }
128
129 runp = runp->next;
130 }
131
132 if (best_bit != 0)
133 {
134 info->user |= best_bit;
135 *format = best_cp;
136 return 0;
137 }
138
139 return 1;
140}
141
142
143int
144attribute_hidden
145__handle_registered_modifier_wc (const unsigned int **format,
146 struct printf_info *info)
147{
148 struct printf_modifier_record *runp = __printf_modifier_table[**format];
149
150 int best_bit = 0;
151 int best_len = 0;
152 const unsigned int *best_cp = NULL;
153
154 while (runp != NULL)
155 {
156 const unsigned int *cp = *format + 1;
157 wchar_t *fcp = runp->str;
158
159 while (*cp != '\0' && *fcp != L'\0')
160 if (*cp != *fcp)
161 break;
162 else
163 ++cp, ++fcp;
164
165 if (*fcp == L'\0' && cp - *format > best_len)
166 {
167 best_cp = cp;
168 best_len = cp - *format;
169 best_bit = runp->bit;
170 }
171
172 runp = runp->next;
173 }
174
175 if (best_bit != 0)
176 {
177 info->user |= best_bit;
178 *format = best_cp;
179 return 0;
180 }
181
182 return 1;
183}
184
185
186void
187__libc_printf_freemem (void)
188{
189 if (__printf_modifier_table != NULL)
190 {
191 for (int i = 0; i < UCHAR_MAX; ++i)
192 {
193 struct printf_modifier_record *runp = __printf_modifier_table[i];
194 while (runp != NULL)
195 {
196 struct printf_modifier_record *oldp = runp;
197 runp = runp->next;
198 free (ptr: oldp);
199 }
200 }
201 free (ptr: __printf_modifier_table);
202 }
203}
204

source code of glibc/stdio-common/reg-modifier.c