1 | /* Miscellaneous support functions for dynamic linker |
2 | Copyright (C) 1997-2017 Free Software Foundation, Inc. |
3 | This file is part of the 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 | <http://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <assert.h> |
20 | #include <fcntl.h> |
21 | #include <ldsodefs.h> |
22 | #include <limits.h> |
23 | #include <link.h> |
24 | #include <stdarg.h> |
25 | #include <stdlib.h> |
26 | #include <string.h> |
27 | #include <unistd.h> |
28 | #include <stdint.h> |
29 | #include <sys/mman.h> |
30 | #include <sys/param.h> |
31 | #include <sys/stat.h> |
32 | #include <sys/uio.h> |
33 | #include <sysdep.h> |
34 | #include <_itoa.h> |
35 | #include <dl-writev.h> |
36 | |
37 | |
38 | /* Read the whole contents of FILE into new mmap'd space with given |
39 | protections. *SIZEP gets the size of the file. On error MAP_FAILED |
40 | is returned. */ |
41 | |
42 | void * |
43 | internal_function |
44 | _dl_sysdep_read_whole_file (const char *file, size_t *sizep, int prot) |
45 | { |
46 | void *result = MAP_FAILED; |
47 | struct stat64 st; |
48 | int flags = O_RDONLY; |
49 | #ifdef O_CLOEXEC |
50 | flags |= O_CLOEXEC; |
51 | #endif |
52 | int fd = __open (file, flags); |
53 | if (fd >= 0) |
54 | { |
55 | if (__fxstat64 (_STAT_VER, fd, &st) >= 0) |
56 | { |
57 | *sizep = st.st_size; |
58 | |
59 | /* No need to map the file if it is empty. */ |
60 | if (*sizep != 0) |
61 | /* Map a copy of the file contents. */ |
62 | result = __mmap (NULL, *sizep, prot, |
63 | #ifdef MAP_COPY |
64 | MAP_COPY |
65 | #else |
66 | MAP_PRIVATE |
67 | #endif |
68 | #ifdef MAP_FILE |
69 | | MAP_FILE |
70 | #endif |
71 | , fd, 0); |
72 | } |
73 | __close (fd); |
74 | } |
75 | return result; |
76 | } |
77 | |
78 | |
79 | /* Bare-bones printf implementation. This function only knows about |
80 | the formats and flags needed and can handle only up to 64 stripes in |
81 | the output. */ |
82 | static void |
83 | _dl_debug_vdprintf (int fd, int tag_p, const char *fmt, va_list arg) |
84 | { |
85 | # define NIOVMAX 64 |
86 | struct iovec iov[NIOVMAX]; |
87 | int niov = 0; |
88 | pid_t pid = 0; |
89 | char pidbuf[12]; |
90 | |
91 | while (*fmt != '\0') |
92 | { |
93 | const char *startp = fmt; |
94 | |
95 | if (tag_p > 0) |
96 | { |
97 | /* Generate the tag line once. It consists of the PID and a |
98 | colon followed by a tab. */ |
99 | if (pid == 0) |
100 | { |
101 | char *p; |
102 | pid = __getpid (); |
103 | assert (pid >= 0 && sizeof (pid_t) <= 4); |
104 | p = _itoa (pid, &pidbuf[10], 10, 0); |
105 | while (p > pidbuf) |
106 | *--p = ' '; |
107 | pidbuf[10] = ':'; |
108 | pidbuf[11] = '\t'; |
109 | } |
110 | |
111 | /* Append to the output. */ |
112 | assert (niov < NIOVMAX); |
113 | iov[niov].iov_len = 12; |
114 | iov[niov++].iov_base = pidbuf; |
115 | |
116 | /* No more tags until we see the next newline. */ |
117 | tag_p = -1; |
118 | } |
119 | |
120 | /* Skip everything except % and \n (if tags are needed). */ |
121 | while (*fmt != '\0' && *fmt != '%' && (! tag_p || *fmt != '\n')) |
122 | ++fmt; |
123 | |
124 | /* Append constant string. */ |
125 | assert (niov < NIOVMAX); |
126 | if ((iov[niov].iov_len = fmt - startp) != 0) |
127 | iov[niov++].iov_base = (char *) startp; |
128 | |
129 | if (*fmt == '%') |
130 | { |
131 | /* It is a format specifier. */ |
132 | char fill = ' '; |
133 | int width = -1; |
134 | int prec = -1; |
135 | #if LONG_MAX != INT_MAX |
136 | int long_mod = 0; |
137 | #endif |
138 | |
139 | /* Recognize zero-digit fill flag. */ |
140 | if (*++fmt == '0') |
141 | { |
142 | fill = '0'; |
143 | ++fmt; |
144 | } |
145 | |
146 | /* See whether with comes from a parameter. Note that no other |
147 | way to specify the width is implemented. */ |
148 | if (*fmt == '*') |
149 | { |
150 | width = va_arg (arg, int); |
151 | ++fmt; |
152 | } |
153 | |
154 | /* Handle precision. */ |
155 | if (*fmt == '.' && fmt[1] == '*') |
156 | { |
157 | prec = va_arg (arg, int); |
158 | fmt += 2; |
159 | } |
160 | |
161 | /* Recognize the l modifier. It is only important on some |
162 | platforms where long and int have a different size. We |
163 | can use the same code for size_t. */ |
164 | if (*fmt == 'l' || *fmt == 'Z') |
165 | { |
166 | #if LONG_MAX != INT_MAX |
167 | long_mod = 1; |
168 | #endif |
169 | ++fmt; |
170 | } |
171 | |
172 | switch (*fmt) |
173 | { |
174 | /* Integer formatting. */ |
175 | case 'u': |
176 | case 'x': |
177 | { |
178 | /* We have to make a difference if long and int have a |
179 | different size. */ |
180 | #if LONG_MAX != INT_MAX |
181 | unsigned long int num = (long_mod |
182 | ? va_arg (arg, unsigned long int) |
183 | : va_arg (arg, unsigned int)); |
184 | #else |
185 | unsigned long int num = va_arg (arg, unsigned int); |
186 | #endif |
187 | /* We use alloca() to allocate the buffer with the most |
188 | pessimistic guess for the size. Using alloca() allows |
189 | having more than one integer formatting in a call. */ |
190 | char *buf = (char *) alloca (3 * sizeof (unsigned long int)); |
191 | char *endp = &buf[3 * sizeof (unsigned long int)]; |
192 | char *cp = _itoa (num, endp, *fmt == 'x' ? 16 : 10, 0); |
193 | |
194 | /* Pad to the width the user specified. */ |
195 | if (width != -1) |
196 | while (endp - cp < width) |
197 | *--cp = fill; |
198 | |
199 | iov[niov].iov_base = cp; |
200 | iov[niov].iov_len = endp - cp; |
201 | ++niov; |
202 | } |
203 | break; |
204 | |
205 | case 's': |
206 | /* Get the string argument. */ |
207 | iov[niov].iov_base = va_arg (arg, char *); |
208 | iov[niov].iov_len = strlen (iov[niov].iov_base); |
209 | if (prec != -1) |
210 | iov[niov].iov_len = MIN ((size_t) prec, iov[niov].iov_len); |
211 | ++niov; |
212 | break; |
213 | |
214 | case '%': |
215 | iov[niov].iov_base = (void *) fmt; |
216 | iov[niov].iov_len = 1; |
217 | ++niov; |
218 | break; |
219 | |
220 | default: |
221 | assert (! "invalid format specifier" ); |
222 | } |
223 | ++fmt; |
224 | } |
225 | else if (*fmt == '\n') |
226 | { |
227 | /* See whether we have to print a single newline character. */ |
228 | if (fmt == startp) |
229 | { |
230 | iov[niov].iov_base = (char *) startp; |
231 | iov[niov++].iov_len = 1; |
232 | } |
233 | else |
234 | /* No, just add it to the rest of the string. */ |
235 | ++iov[niov - 1].iov_len; |
236 | |
237 | /* Next line, print a tag again. */ |
238 | tag_p = 1; |
239 | ++fmt; |
240 | } |
241 | } |
242 | |
243 | /* Finally write the result. */ |
244 | _dl_writev (fd, iov, niov); |
245 | } |
246 | |
247 | |
248 | /* Write to debug file. */ |
249 | void |
250 | _dl_debug_printf (const char *fmt, ...) |
251 | { |
252 | va_list arg; |
253 | |
254 | va_start (arg, fmt); |
255 | _dl_debug_vdprintf (GLRO(dl_debug_fd), 1, fmt, arg); |
256 | va_end (arg); |
257 | } |
258 | |
259 | |
260 | /* Write to debug file but don't start with a tag. */ |
261 | void |
262 | _dl_debug_printf_c (const char *fmt, ...) |
263 | { |
264 | va_list arg; |
265 | |
266 | va_start (arg, fmt); |
267 | _dl_debug_vdprintf (GLRO(dl_debug_fd), -1, fmt, arg); |
268 | va_end (arg); |
269 | } |
270 | |
271 | |
272 | /* Write the given file descriptor. */ |
273 | void |
274 | _dl_dprintf (int fd, const char *fmt, ...) |
275 | { |
276 | va_list arg; |
277 | |
278 | va_start (arg, fmt); |
279 | _dl_debug_vdprintf (fd, 0, fmt, arg); |
280 | va_end (arg); |
281 | } |
282 | |
283 | |
284 | /* Test whether given NAME matches any of the names of the given object. */ |
285 | int |
286 | internal_function |
287 | _dl_name_match_p (const char *name, const struct link_map *map) |
288 | { |
289 | if (strcmp (name, map->l_name) == 0) |
290 | return 1; |
291 | |
292 | struct libname_list *runp = map->l_libname; |
293 | |
294 | while (runp != NULL) |
295 | if (strcmp (name, runp->name) == 0) |
296 | return 1; |
297 | else |
298 | runp = runp->next; |
299 | |
300 | return 0; |
301 | } |
302 | |
303 | |
304 | unsigned long int |
305 | internal_function |
306 | _dl_higher_prime_number (unsigned long int n) |
307 | { |
308 | /* These are primes that are near, but slightly smaller than, a |
309 | power of two. */ |
310 | static const uint32_t primes[] = { |
311 | UINT32_C (7), |
312 | UINT32_C (13), |
313 | UINT32_C (31), |
314 | UINT32_C (61), |
315 | UINT32_C (127), |
316 | UINT32_C (251), |
317 | UINT32_C (509), |
318 | UINT32_C (1021), |
319 | UINT32_C (2039), |
320 | UINT32_C (4093), |
321 | UINT32_C (8191), |
322 | UINT32_C (16381), |
323 | UINT32_C (32749), |
324 | UINT32_C (65521), |
325 | UINT32_C (131071), |
326 | UINT32_C (262139), |
327 | UINT32_C (524287), |
328 | UINT32_C (1048573), |
329 | UINT32_C (2097143), |
330 | UINT32_C (4194301), |
331 | UINT32_C (8388593), |
332 | UINT32_C (16777213), |
333 | UINT32_C (33554393), |
334 | UINT32_C (67108859), |
335 | UINT32_C (134217689), |
336 | UINT32_C (268435399), |
337 | UINT32_C (536870909), |
338 | UINT32_C (1073741789), |
339 | UINT32_C (2147483647), |
340 | /* 4294967291L */ |
341 | UINT32_C (2147483647) + UINT32_C (2147483644) |
342 | }; |
343 | |
344 | const uint32_t *low = &primes[0]; |
345 | const uint32_t *high = &primes[sizeof (primes) / sizeof (primes[0])]; |
346 | |
347 | while (low != high) |
348 | { |
349 | const uint32_t *mid = low + (high - low) / 2; |
350 | if (n > *mid) |
351 | low = mid + 1; |
352 | else |
353 | high = mid; |
354 | } |
355 | |
356 | #if 0 |
357 | /* If we've run out of primes, abort. */ |
358 | if (n > *low) |
359 | { |
360 | fprintf (stderr, "Cannot find prime bigger than %lu\n" , n); |
361 | abort (); |
362 | } |
363 | #endif |
364 | |
365 | return *low; |
366 | } |
367 | |