1 /* Internal header for parsing printf format strings.
2 Copyright (C) 1995-2022 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 #ifndef DONT_NEED_READ_INT
48 /* Read a simple integer from a string and update the string pointer.
49 It is assumed that the first character is a digit. */
50 static int
read_int(const UCHAR_T ** pstr)51 read_int (const UCHAR_T * *pstr)
52 {
53 int retval = **pstr - L_('0');
54
55 while (ISDIGIT (*++(*pstr)))
56 if (retval >= 0)
57 {
58 if (INT_MAX / 10 < retval)
59 retval = -1;
60 else
61 {
62 int digit = **pstr - L_('0');
63
64 retval *= 10;
65 if (INT_MAX - digit < retval)
66 retval = -1;
67 else
68 retval += digit;
69 }
70 }
71
72 return retval;
73 }
74 #endif
75
76
77 /* Find the next spec in FORMAT, or the end of the string. Returns
78 a pointer into FORMAT, to a '%' or a '\0'. */
79 __extern_always_inline const unsigned char *
__find_specmb(const unsigned char * format)80 __find_specmb (const unsigned char *format)
81 {
82 return (const unsigned char *) __strchrnul ((const char *) format, '%');
83 }
84
85 __extern_always_inline const unsigned int *
__find_specwc(const unsigned int * format)86 __find_specwc (const unsigned int *format)
87 {
88 return (const unsigned int *) __wcschrnul ((const wchar_t *) format, L'%');
89 }
90
91
92 /* FORMAT must point to a '%' at the beginning of a spec. Fills in *SPEC
93 with the parsed details. POSN is the number of arguments already
94 consumed. At most MAXTYPES - POSN types are filled in TYPES. Return
95 the number of args consumed by this spec; *MAX_REF_ARG is updated so it
96 remains the highest argument index used. */
97 extern size_t __parse_one_specmb (const unsigned char *format, size_t posn,
98 struct printf_spec *spec,
99 size_t *max_ref_arg) attribute_hidden;
100
101 extern size_t __parse_one_specwc (const unsigned int *format, size_t posn,
102 struct printf_spec *spec,
103 size_t *max_ref_arg) attribute_hidden;
104
105
106
107 /* This variable is defined in reg-modifier.c. */
108 struct printf_modifier_record;
109 extern struct printf_modifier_record **__printf_modifier_table
110 attribute_hidden;
111
112 /* Handle registered modifiers. */
113 extern int __handle_registered_modifier_mb (const unsigned char **format,
114 struct printf_info *info)
115 attribute_hidden;
116 extern int __handle_registered_modifier_wc (const unsigned int **format,
117 struct printf_info *info)
118 attribute_hidden;
119