1 /* printf implementation for the dynamic loader.
2 Copyright (C) 1997-2023 Free Software Foundation, Inc.
3 Copyright The GNU Toolchain Authors.
4 This file is part of the GNU C Library.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <https://www.gnu.org/licenses/>. */
22 #include <dl-writev.h>
33 /* Bare-bones printf implementation. This function only knows about
34 the formats and flags needed and can handle only up to 64 stripes in
37 _dl_debug_vdprintf (int fd
, int tag_p
, const char *fmt
, va_list arg
)
40 struct iovec iov
[NIOVMAX
];
41 /* Maximum size for 'd', 'u', and 'x' including padding. */
42 enum { IFMTSIZE
= INT_STRLEN_BOUND(void *) };
43 char ifmtbuf
[NIOVMAX
][IFMTSIZE
];
50 const char *startp
= fmt
;
54 /* Generate the tag line once. It consists of the PID and a
55 colon followed by a tab. */
60 assert (pid
>= 0 && sizeof (pid_t
) <= 4);
61 p
= _itoa (pid
, &pidbuf
[10], 10, 0);
68 /* Append to the output. */
69 assert (niov
< NIOVMAX
);
70 iov
[niov
].iov_len
= 12;
71 iov
[niov
++].iov_base
= pidbuf
;
73 /* No more tags until we see the next newline. */
77 /* Skip everything except % and \n (if tags are needed). */
78 while (*fmt
!= '\0' && *fmt
!= '%' && (! tag_p
|| *fmt
!= '\n'))
81 /* Append constant string. */
82 assert (niov
< NIOVMAX
);
83 if ((iov
[niov
].iov_len
= fmt
- startp
) != 0)
84 iov
[niov
++].iov_base
= (char *) startp
;
88 /* It is a format specifier. */
92 #if LONG_MAX != INT_MAX
96 /* Recognize zero-digit fill flag. */
103 /* See whether with comes from a parameter. Note that no other
104 way to specify the width is implemented. */
107 width
= va_arg (arg
, int);
108 /* The maximum padding accepted is up to pointer size. */
109 assert (width
< IFMTSIZE
);
113 /* Handle precision. */
114 if (*fmt
== '.' && fmt
[1] == '*')
116 prec
= va_arg (arg
, int);
120 /* Recognize the l modifier. It is only important on some
121 platforms where long and int have a different size. We
122 can use the same code for size_t. */
123 if (*fmt
== 'l' || *fmt
== 'z')
125 #if LONG_MAX != INT_MAX
133 /* Integer formatting. */
138 /* We have to make a difference if long and int have a
140 #if LONG_MAX != INT_MAX
141 unsigned long int num
= (long_mod
142 ? va_arg (arg
, unsigned long int)
143 : va_arg (arg
, unsigned int));
145 unsigned long int num
= va_arg (arg
, unsigned int);
147 bool negative
= false;
150 #if LONG_MAX != INT_MAX
153 if ((long int) num
< 0)
163 num
= -(unsigned int) num
;
176 char *endp
= &ifmtbuf
[niov
][IFMTSIZE
];
177 char *cp
= _itoa (num
, endp
, *fmt
== 'x' ? 16 : 10, 0);
179 /* Pad to the width the user specified. */
181 while (endp
- cp
< width
)
187 iov
[niov
].iov_base
= cp
;
188 iov
[niov
].iov_len
= endp
- cp
;
194 /* Get the string argument. */
195 iov
[niov
].iov_base
= va_arg (arg
, char *);
196 iov
[niov
].iov_len
= strlen (iov
[niov
].iov_base
);
198 iov
[niov
].iov_len
= MIN ((size_t) prec
, iov
[niov
].iov_len
);
203 iov
[niov
].iov_base
= (void *) fmt
;
204 iov
[niov
].iov_len
= 1;
209 assert (! "invalid format specifier");
213 else if (*fmt
== '\n')
215 /* See whether we have to print a single newline character. */
218 iov
[niov
].iov_base
= (char *) startp
;
219 iov
[niov
++].iov_len
= 1;
222 /* No, just add it to the rest of the string. */
223 ++iov
[niov
- 1].iov_len
;
225 /* Next line, print a tag again. */
231 /* Finally write the result. */
232 _dl_writev (fd
, iov
, niov
);
236 /* Write to debug file. */
238 _dl_debug_printf (const char *fmt
, ...)
243 _dl_debug_vdprintf (GLRO(dl_debug_fd
), 1, fmt
, arg
);
248 /* Write to debug file but don't start with a tag. */
250 _dl_debug_printf_c (const char *fmt
, ...)
255 _dl_debug_vdprintf (GLRO(dl_debug_fd
), -1, fmt
, arg
);
260 /* Write the given file descriptor. */
262 _dl_dprintf (int fd
, const char *fmt
, ...)
267 _dl_debug_vdprintf (fd
, 0, fmt
, arg
);
272 _dl_printf (const char *fmt
, ...)
277 _dl_debug_vdprintf (STDOUT_FILENO
, 0, fmt
, arg
);
282 _dl_error_printf (const char *fmt
, ...)
287 _dl_debug_vdprintf (STDERR_FILENO
, 0, fmt
, arg
);
292 _dl_fatal_printf (const char *fmt
, ...)
297 _dl_debug_vdprintf (STDERR_FILENO
, 0, fmt
, arg
);
301 rtld_hidden_def (_dl_fatal_printf
)