1 /* Internal header for parsing printf format strings.
2 Copyright (C) 1995-2021 Free Software Foundation, Inc.
3 This file is part of th GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19 #include <printf.h>
20 #include <stdint.h>
21 #include <stddef.h>
22 #include <string.h>
23 #include <wchar.h>
24
25
26 struct printf_spec
27 {
28 /* Information parsed from the format spec. */
29 struct printf_info info;
30
31 /* Pointers into the format string for the end of this format
32 spec and the next (or to the end of the string if no more). */
33 const UCHAR_T *end_of_fmt, *next_fmt;
34
35 /* Position of arguments for precision and width, or -1 if `info' has
36 the constant value. */
37 int prec_arg, width_arg;
38
39 int data_arg; /* Position of data argument. */
40 int data_arg_type; /* Type of first argument. */
41 /* Number of arguments consumed by this format specifier. */
42 size_t ndata_args;
43 /* Size of the parameter for PA_USER type. */
44 int size;
45 };
46
47
48 /* The various kinds off arguments that can be passed to printf. */
49 union printf_arg
50 {
51 wchar_t pa_wchar;
52 int pa_int;
53 long int pa_long_int;
54 long long int pa_long_long_int;
55 unsigned int pa_u_int;
56 unsigned long int pa_u_long_int;
57 unsigned long long int pa_u_long_long_int;
58 double pa_double;
59 long double pa_long_double;
60 #if __HAVE_FLOAT128_UNLIKE_LDBL
61 _Float128 pa_float128;
62 #endif
63 const char *pa_string;
64 const wchar_t *pa_wstring;
65 void *pa_pointer;
66 void *pa_user;
67 };
68
69
70 #ifndef DONT_NEED_READ_INT
71 /* Read a simple integer from a string and update the string pointer.
72 It is assumed that the first character is a digit. */
73 static int
read_int(const UCHAR_T ** pstr)74 read_int (const UCHAR_T * *pstr)
75 {
76 int retval = **pstr - L_('0');
77
78 while (ISDIGIT (*++(*pstr)))
79 if (retval >= 0)
80 {
81 if (INT_MAX / 10 < retval)
82 retval = -1;
83 else
84 {
85 int digit = **pstr - L_('0');
86
87 retval *= 10;
88 if (INT_MAX - digit < retval)
89 retval = -1;
90 else
91 retval += digit;
92 }
93 }
94
95 return retval;
96 }
97 #endif
98
99
100 /* These are defined in reg-printf.c. */
101 extern printf_arginfo_size_function **__printf_arginfo_table attribute_hidden;
102 extern printf_function **__printf_function_table attribute_hidden;
103 extern printf_va_arg_function **__printf_va_arg_table attribute_hidden;
104
105
106 /* Find the next spec in FORMAT, or the end of the string. Returns
107 a pointer into FORMAT, to a '%' or a '\0'. */
108 __extern_always_inline const unsigned char *
__find_specmb(const unsigned char * format)109 __find_specmb (const unsigned char *format)
110 {
111 return (const unsigned char *) __strchrnul ((const char *) format, '%');
112 }
113
114 __extern_always_inline const unsigned int *
__find_specwc(const unsigned int * format)115 __find_specwc (const unsigned int *format)
116 {
117 return (const unsigned int *) __wcschrnul ((const wchar_t *) format, L'%');
118 }
119
120
121 /* FORMAT must point to a '%' at the beginning of a spec. Fills in *SPEC
122 with the parsed details. POSN is the number of arguments already
123 consumed. At most MAXTYPES - POSN types are filled in TYPES. Return
124 the number of args consumed by this spec; *MAX_REF_ARG is updated so it
125 remains the highest argument index used. */
126 extern size_t __parse_one_specmb (const unsigned char *format, size_t posn,
127 struct printf_spec *spec,
128 size_t *max_ref_arg) attribute_hidden;
129
130 extern size_t __parse_one_specwc (const unsigned int *format, size_t posn,
131 struct printf_spec *spec,
132 size_t *max_ref_arg) attribute_hidden;
133
134
135
136 /* This variable is defined in reg-modifier.c. */
137 struct printf_modifier_record;
138 extern struct printf_modifier_record **__printf_modifier_table
139 attribute_hidden;
140
141 /* Handle registered modifiers. */
142 extern int __handle_registered_modifier_mb (const unsigned char **format,
143 struct printf_info *info)
144 attribute_hidden;
145 extern int __handle_registered_modifier_wc (const unsigned int **format,
146 struct printf_info *info)
147 attribute_hidden;
148