Go to most recent revision | Details | Last modification | View Log | RSS feed
Rev | Author | Line No. | Line |
---|---|---|---|
5199 | serge | 1 | /* ldctor.c -- constructor support routines |
2 | Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, |
||
3 | 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2011 |
||
4 | Free Software Foundation, Inc. |
||
5 | By Steve Chamberlain |
||
6 | |||
7 | This file is part of the GNU Binutils. |
||
8 | |||
9 | This program is free software; you can redistribute it and/or modify |
||
10 | it under the terms of the GNU General Public License as published by |
||
11 | the Free Software Foundation; either version 3 of the License, or |
||
12 | (at your option) any later version. |
||
13 | |||
14 | This program is distributed in the hope that it will be useful, |
||
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
||
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
||
17 | GNU General Public License for more details. |
||
18 | |||
19 | You should have received a copy of the GNU General Public License |
||
20 | along with this program; if not, write to the Free Software |
||
21 | Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
||
22 | MA 02110-1301, USA. */ |
||
23 | |||
24 | #include "sysdep.h" |
||
25 | #include "bfd.h" |
||
26 | #include "bfdlink.h" |
||
27 | #include "safe-ctype.h" |
||
28 | |||
29 | #include "ld.h" |
||
30 | #include "ldexp.h" |
||
31 | #include "ldlang.h" |
||
32 | #include "ldmisc.h" |
||
33 | #include |
||
34 | #include "ldmain.h" |
||
35 | #include "ldctor.h" |
||
36 | |||
37 | /* The list of statements needed to handle constructors. These are |
||
38 | invoked by the command CONSTRUCTORS in the linker script. */ |
||
39 | lang_statement_list_type constructor_list; |
||
40 | |||
41 | /* Whether the constructors should be sorted. Note that this is |
||
42 | global for the entire link; we assume that there is only a single |
||
43 | CONSTRUCTORS command in the linker script. */ |
||
44 | bfd_boolean constructors_sorted; |
||
45 | |||
46 | /* The sets we have seen. */ |
||
47 | struct set_info *sets; |
||
48 | |||
49 | /* Add an entry to a set. H is the entry in the linker hash table. |
||
50 | RELOC is the relocation to use for an entry in the set. SECTION |
||
51 | and VALUE are the value to add. This is called during the first |
||
52 | phase of the link, when we are still gathering symbols together. |
||
53 | We just record the information now. The ldctor_build_sets |
||
54 | function will construct the sets. */ |
||
55 | |||
56 | void |
||
57 | ldctor_add_set_entry (struct bfd_link_hash_entry *h, |
||
58 | bfd_reloc_code_real_type reloc, |
||
59 | const char *name, |
||
60 | asection *section, |
||
61 | bfd_vma value) |
||
62 | { |
||
63 | struct set_info *p; |
||
64 | struct set_element *e; |
||
65 | struct set_element **epp; |
||
66 | |||
67 | for (p = sets; p != NULL; p = p->next) |
||
68 | if (p->h == h) |
||
69 | break; |
||
70 | |||
71 | if (p == NULL) |
||
72 | { |
||
73 | p = (struct set_info *) xmalloc (sizeof (struct set_info)); |
||
74 | p->next = sets; |
||
75 | sets = p; |
||
76 | p->h = h; |
||
77 | p->reloc = reloc; |
||
78 | p->count = 0; |
||
79 | p->elements = NULL; |
||
80 | } |
||
81 | else |
||
82 | { |
||
83 | if (p->reloc != reloc) |
||
84 | { |
||
85 | einfo (_("%P%X: Different relocs used in set %s\n"), |
||
86 | h->root.string); |
||
87 | return; |
||
88 | } |
||
89 | |||
90 | /* Don't permit a set to be constructed from different object |
||
91 | file formats. The same reloc may have different results. We |
||
92 | actually could sometimes handle this, but the case is |
||
93 | unlikely to ever arise. Sometimes constructor symbols are in |
||
94 | unusual sections, such as the absolute section--this appears |
||
95 | to be the case in Linux a.out--and in such cases we just |
||
96 | assume everything is OK. */ |
||
97 | if (p->elements != NULL |
||
98 | && section->owner != NULL |
||
99 | && p->elements->section->owner != NULL |
||
100 | && strcmp (bfd_get_target (section->owner), |
||
101 | bfd_get_target (p->elements->section->owner)) != 0) |
||
102 | { |
||
103 | einfo (_("%P%X: Different object file formats composing set %s\n"), |
||
104 | h->root.string); |
||
105 | return; |
||
106 | } |
||
107 | } |
||
108 | |||
109 | e = (struct set_element *) xmalloc (sizeof (struct set_element)); |
||
110 | e->next = NULL; |
||
111 | e->name = name; |
||
112 | e->section = section; |
||
113 | e->value = value; |
||
114 | |||
115 | for (epp = &p->elements; *epp != NULL; epp = &(*epp)->next) |
||
116 | ; |
||
117 | *epp = e; |
||
118 | |||
119 | ++p->count; |
||
120 | } |
||
121 | |||
122 | /* Get the priority of a g++ global constructor or destructor from the |
||
123 | symbol name. */ |
||
124 | |||
125 | static int |
||
126 | ctor_prio (const char *name) |
||
127 | { |
||
128 | /* The name will look something like _GLOBAL_$I$65535$test02__Fv. |
||
129 | There might be extra leading underscores, and the $ characters |
||
130 | might be something else. The I might be a D. */ |
||
131 | |||
132 | while (*name == '_') |
||
133 | ++name; |
||
134 | |||
135 | if (! CONST_STRNEQ (name, "GLOBAL_")) |
||
136 | return -1; |
||
137 | |||
138 | name += sizeof "GLOBAL_" - 1; |
||
139 | |||
140 | if (name[0] != name[2]) |
||
141 | return -1; |
||
142 | if (name[1] != 'I' && name[1] != 'D') |
||
143 | return -1; |
||
144 | if (! ISDIGIT (name[3])) |
||
145 | return -1; |
||
146 | |||
147 | return atoi (name + 3); |
||
148 | } |
||
149 | |||
150 | /* This function is used to sort constructor elements by priority. It |
||
151 | is called via qsort. */ |
||
152 | |||
153 | static int |
||
154 | ctor_cmp (const void *p1, const void *p2) |
||
155 | { |
||
156 | const struct set_element * const *pe1 = |
||
157 | (const struct set_element * const *) p1; |
||
158 | const struct set_element * const *pe2 = |
||
159 | (const struct set_element * const *) p2; |
||
160 | const char *n1; |
||
161 | const char *n2; |
||
162 | int prio1; |
||
163 | int prio2; |
||
164 | |||
165 | n1 = (*pe1)->name; |
||
166 | if (n1 == NULL) |
||
167 | n1 = ""; |
||
168 | n2 = (*pe2)->name; |
||
169 | if (n2 == NULL) |
||
170 | n2 = ""; |
||
171 | |||
172 | /* We need to sort in reverse order by priority. When two |
||
173 | constructors have the same priority, we should maintain their |
||
174 | current relative position. */ |
||
175 | |||
176 | prio1 = ctor_prio (n1); |
||
177 | prio2 = ctor_prio (n2); |
||
178 | |||
179 | /* We sort in reverse order because that is what g++ expects. */ |
||
180 | if (prio1 < prio2) |
||
181 | return 1; |
||
182 | else if (prio1 > prio2) |
||
183 | return -1; |
||
184 | |||
185 | /* Force a stable sort. */ |
||
186 | |||
187 | if (pe1 < pe2) |
||
188 | return -1; |
||
189 | else if (pe1 > pe2) |
||
190 | return 1; |
||
191 | else |
||
192 | return 0; |
||
193 | } |
||
194 | |||
195 | /* This function is called after the first phase of the link and |
||
196 | before the second phase. At this point all set information has |
||
197 | been gathered. We now put the statements to build the sets |
||
198 | themselves into constructor_list. */ |
||
199 | |||
200 | void |
||
201 | ldctor_build_sets (void) |
||
202 | { |
||
203 | static bfd_boolean called; |
||
204 | bfd_boolean header_printed; |
||
205 | struct set_info *p; |
||
206 | |||
207 | /* The emulation code may call us directly, but we only want to do |
||
208 | this once. */ |
||
209 | if (called) |
||
210 | return; |
||
211 | called = TRUE; |
||
212 | |||
213 | if (constructors_sorted) |
||
214 | { |
||
215 | for (p = sets; p != NULL; p = p->next) |
||
216 | { |
||
217 | int c, i; |
||
218 | struct set_element *e; |
||
219 | struct set_element **array; |
||
220 | |||
221 | if (p->elements == NULL) |
||
222 | continue; |
||
223 | |||
224 | c = 0; |
||
225 | for (e = p->elements; e != NULL; e = e->next) |
||
226 | ++c; |
||
227 | |||
228 | array = (struct set_element **) xmalloc (c * sizeof *array); |
||
229 | |||
230 | i = 0; |
||
231 | for (e = p->elements; e != NULL; e = e->next) |
||
232 | { |
||
233 | array[i] = e; |
||
234 | ++i; |
||
235 | } |
||
236 | |||
237 | qsort (array, c, sizeof *array, ctor_cmp); |
||
238 | |||
239 | e = array[0]; |
||
240 | p->elements = e; |
||
241 | for (i = 0; i < c - 1; i++) |
||
242 | array[i]->next = array[i + 1]; |
||
243 | array[i]->next = NULL; |
||
244 | |||
245 | free (array); |
||
246 | } |
||
247 | } |
||
248 | |||
249 | lang_list_init (&constructor_list); |
||
250 | push_stat_ptr (&constructor_list); |
||
251 | |||
252 | header_printed = FALSE; |
||
253 | for (p = sets; p != NULL; p = p->next) |
||
254 | { |
||
255 | struct set_element *e; |
||
256 | reloc_howto_type *howto; |
||
257 | int reloc_size, size; |
||
258 | |||
259 | /* If the symbol is defined, we may have been invoked from |
||
260 | collect, and the sets may already have been built, so we do |
||
261 | not do anything. */ |
||
262 | if (p->h->type == bfd_link_hash_defined |
||
263 | || p->h->type == bfd_link_hash_defweak) |
||
264 | continue; |
||
265 | |||
266 | /* For each set we build: |
||
267 | set: |
||
268 | .long number_of_elements |
||
269 | .long element0 |
||
270 | ... |
||
271 | .long elementN |
||
272 | .long 0 |
||
273 | except that we use the right size instead of .long. When |
||
274 | generating relocatable output, we generate relocs instead of |
||
275 | addresses. */ |
||
276 | howto = bfd_reloc_type_lookup (link_info.output_bfd, p->reloc); |
||
277 | if (howto == NULL) |
||
278 | { |
||
279 | if (link_info.relocatable) |
||
280 | { |
||
281 | einfo (_("%P%X: %s does not support reloc %s for set %s\n"), |
||
282 | bfd_get_target (link_info.output_bfd), |
||
283 | bfd_get_reloc_code_name (p->reloc), |
||
284 | p->h->root.string); |
||
285 | continue; |
||
286 | } |
||
287 | |||
288 | /* If this is not a relocatable link, all we need is the |
||
289 | size, which we can get from the input BFD. */ |
||
290 | if (p->elements->section->owner != NULL) |
||
291 | howto = bfd_reloc_type_lookup (p->elements->section->owner, |
||
292 | p->reloc); |
||
293 | if (howto == NULL) |
||
294 | { |
||
295 | einfo (_("%P%X: %s does not support reloc %s for set %s\n"), |
||
296 | bfd_get_target (p->elements->section->owner), |
||
297 | bfd_get_reloc_code_name (p->reloc), |
||
298 | p->h->root.string); |
||
299 | continue; |
||
300 | } |
||
301 | } |
||
302 | |||
303 | reloc_size = bfd_get_reloc_size (howto); |
||
304 | switch (reloc_size) |
||
305 | { |
||
306 | case 1: size = BYTE; break; |
||
307 | case 2: size = SHORT; break; |
||
308 | case 4: size = LONG; break; |
||
309 | case 8: |
||
310 | if (howto->complain_on_overflow == complain_overflow_signed) |
||
311 | size = SQUAD; |
||
312 | else |
||
313 | size = QUAD; |
||
314 | break; |
||
315 | default: |
||
316 | einfo (_("%P%X: Unsupported size %d for set %s\n"), |
||
317 | bfd_get_reloc_size (howto), p->h->root.string); |
||
318 | size = LONG; |
||
319 | break; |
||
320 | } |
||
321 | |||
322 | lang_add_assignment (exp_assign (".", |
||
323 | exp_unop (ALIGN_K, |
||
324 | exp_intop (reloc_size)), |
||
325 | FALSE)); |
||
326 | lang_add_assignment (exp_assign (p->h->root.string, |
||
327 | exp_nameop (NAME, "."), |
||
328 | FALSE)); |
||
329 | lang_add_data (size, exp_intop (p->count)); |
||
330 | |||
331 | for (e = p->elements; e != NULL; e = e->next) |
||
332 | { |
||
333 | if (config.map_file != NULL) |
||
334 | { |
||
335 | int len; |
||
336 | |||
337 | if (! header_printed) |
||
338 | { |
||
339 | minfo (_("\nSet Symbol\n\n")); |
||
340 | header_printed = TRUE; |
||
341 | } |
||
342 | |||
343 | minfo ("%s", p->h->root.string); |
||
344 | len = strlen (p->h->root.string); |
||
345 | |||
346 | if (len >= 19) |
||
347 | { |
||
348 | print_nl (); |
||
349 | len = 0; |
||
350 | } |
||
351 | while (len < 20) |
||
352 | { |
||
353 | print_space (); |
||
354 | ++len; |
||
355 | } |
||
356 | |||
357 | if (e->name != NULL) |
||
358 | minfo ("%T\n", e->name); |
||
359 | else |
||
360 | minfo ("%G\n", e->section->owner, e->section, e->value); |
||
361 | } |
||
362 | |||
363 | /* Need SEC_KEEP for --gc-sections. */ |
||
364 | if (! bfd_is_abs_section (e->section)) |
||
365 | e->section->flags |= SEC_KEEP; |
||
366 | |||
367 | if (link_info.relocatable) |
||
368 | lang_add_reloc (p->reloc, howto, e->section, e->name, |
||
369 | exp_intop (e->value)); |
||
370 | else |
||
371 | lang_add_data (size, exp_relop (e->section, e->value)); |
||
372 | } |
||
373 | |||
374 | lang_add_data (size, exp_intop (0)); |
||
375 | } |
||
376 | |||
377 | pop_stat_ptr (); |
||
378 | }>>>> |