1 /* printf implementation for the dynamic loader.
2 Copyright (C) 1997-2024 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 # pragma GCC visibility push(hidden)
26 #include <dl-writev.h>
36 /* The function might be called before the process is self-relocated. */
38 _dl_debug_strlen (const char *s
)
41 for (; *s
!= '\0'; s
++);
45 /* Bare-bones printf implementation. This function only knows about
46 the formats and flags needed and can handle only up to 64 stripes in
49 _dl_debug_vdprintf (int fd
, int tag_p
, const char *fmt
, va_list arg
)
52 struct iovec iov
[NIOVMAX
];
53 /* Maximum size for 'd', 'u', and 'x' including padding. */
54 enum { IFMTSIZE
= INT_STRLEN_BOUND(void *) };
55 char ifmtbuf
[NIOVMAX
][IFMTSIZE
];
62 const char *startp
= fmt
;
66 /* Generate the tag line once. It consists of the PID and a
67 colon followed by a tab. */
72 assert (pid
>= 0 && sizeof (pid_t
) <= 4);
73 p
= _itoa (pid
, &pidbuf
[10], 10, 0);
80 /* Append to the output. */
81 assert (niov
< NIOVMAX
);
82 iov
[niov
].iov_len
= 12;
83 iov
[niov
++].iov_base
= pidbuf
;
85 /* No more tags until we see the next newline. */
89 /* Skip everything except % and \n (if tags are needed). */
90 while (*fmt
!= '\0' && *fmt
!= '%' && (! tag_p
|| *fmt
!= '\n'))
93 /* Append constant string. */
94 assert (niov
< NIOVMAX
);
95 if ((iov
[niov
].iov_len
= fmt
- startp
) != 0)
96 iov
[niov
++].iov_base
= (char *) startp
;
100 /* It is a format specifier. */
104 #if LONG_MAX != INT_MAX
108 /* Recognize zero-digit fill flag. */
115 /* See whether with comes from a parameter. Note that no other
116 way to specify the width is implemented. */
119 width
= va_arg (arg
, int);
120 /* The maximum padding accepted is up to pointer size. */
121 assert (width
< IFMTSIZE
);
125 /* Handle precision. */
126 if (*fmt
== '.' && fmt
[1] == '*')
128 prec
= va_arg (arg
, int);
132 /* Recognize the l modifier. It is only important on some
133 platforms where long and int have a different size. We
134 can use the same code for size_t. */
135 if (*fmt
== 'l' || *fmt
== 'z')
137 #if LONG_MAX != INT_MAX
145 /* Integer formatting. */
150 /* We have to make a difference if long and int have a
152 #if LONG_MAX != INT_MAX
153 unsigned long int num
= (long_mod
154 ? va_arg (arg
, unsigned long int)
155 : va_arg (arg
, unsigned int));
157 unsigned long int num
= va_arg (arg
, unsigned int);
159 bool negative
= false;
162 #if LONG_MAX != INT_MAX
165 if ((long int) num
< 0)
175 num
= -(unsigned int) num
;
188 char *endp
= &ifmtbuf
[niov
][IFMTSIZE
];
189 char *cp
= _itoa (num
, endp
, *fmt
== 'x' ? 16 : 10, 0);
191 /* Pad to the width the user specified. */
193 while (endp
- cp
< width
)
199 iov
[niov
].iov_base
= cp
;
200 iov
[niov
].iov_len
= endp
- cp
;
206 /* Get the string argument. */
207 iov
[niov
].iov_base
= va_arg (arg
, char *);
208 iov
[niov
].iov_len
= _dl_debug_strlen (iov
[niov
].iov_base
);
210 iov
[niov
].iov_len
= MIN ((size_t) prec
, iov
[niov
].iov_len
);
215 iov
[niov
].iov_base
= (void *) fmt
;
216 iov
[niov
].iov_len
= 1;
221 assert (! "invalid format specifier");
225 else if (*fmt
== '\n')
227 /* See whether we have to print a single newline character. */
230 iov
[niov
].iov_base
= (char *) startp
;
231 iov
[niov
++].iov_len
= 1;
234 /* No, just add it to the rest of the string. */
235 ++iov
[niov
- 1].iov_len
;
237 /* Next line, print a tag again. */
243 /* Finally write the result. */
244 _dl_writev (fd
, iov
, niov
);
248 /* Write to debug file. */
250 _dl_debug_printf (const char *fmt
, ...)
255 _dl_debug_vdprintf (GLRO(dl_debug_fd
), 1, fmt
, arg
);
260 /* Write to debug file but don't start with a tag. */
262 _dl_debug_printf_c (const char *fmt
, ...)
267 _dl_debug_vdprintf (GLRO(dl_debug_fd
), -1, fmt
, arg
);
272 /* Write the given file descriptor. */
274 _dl_dprintf (int fd
, const char *fmt
, ...)
279 _dl_debug_vdprintf (fd
, 0, fmt
, arg
);
284 _dl_printf (const char *fmt
, ...)
289 _dl_debug_vdprintf (STDOUT_FILENO
, 0, fmt
, arg
);
294 _dl_error_printf (const char *fmt
, ...)
299 _dl_debug_vdprintf (STDERR_FILENO
, 0, fmt
, arg
);
304 _dl_fatal_printf (const char *fmt
, ...)
309 _dl_debug_vdprintf (STDERR_FILENO
, 0, fmt
, arg
);
313 rtld_hidden_def (_dl_fatal_printf
)