1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
|
// target-select.cc -- select a target for an object file
// Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012
// Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
// MA 02110-1301, USA.
#include "gold.h"
#include <cstdio>
#include <cstring>
#include "elfcpp.h"
#include "options.h"
#include "parameters.h"
#include "target-select.h"
namespace
{
// The start of the list of target selectors.
gold::Target_selector* target_selectors;
} // End anonymous namespace.
namespace gold
{
// Class Set_target_once.
void
Set_target_once::do_run_once(void*)
{
this->target_selector_->set_target();
}
// Construct a Target_selector, which means adding it to the linked
// list. This runs at global constructor time, so we want it to be
// fast.
Target_selector::Target_selector(int machine, int size, bool is_big_endian,
const char* bfd_name, const char* emulation)
: machine_(machine), size_(size), is_big_endian_(is_big_endian),
bfd_name_(bfd_name), emulation_(emulation), instantiated_target_(NULL),
set_target_once_(this)
{
this->next_ = target_selectors;
target_selectors = this;
}
// Instantiate the target and return it. Use SET_TARGET_ONCE_ to
// avoid instantiating two instances of the same target.
Target*
Target_selector::instantiate_target()
{
this->set_target_once_.run_once(NULL);
return this->instantiated_target_;
}
// Instantiate the target. This is called at most once.
void
Target_selector::set_target()
{
gold_assert(this->instantiated_target_ == NULL);
this->instantiated_target_ = this->do_instantiate_target();
}
// If we instantiated TARGET, return the corresponding BFD name.
const char*
Target_selector::do_target_bfd_name(const Target* target)
{
if (!this->is_our_target(target))
return NULL;
const char* my_bfd_name = this->bfd_name();
gold_assert(my_bfd_name != NULL);
return my_bfd_name;
}
// Find the target for an ELF file.
Target*
select_target(Input_file* input_file, off_t offset,
int machine, int size, bool is_big_endian,
int osabi, int abiversion)
{
for (Target_selector* p = target_selectors; p != NULL; p = p->next())
{
int pmach = p->machine();
if ((pmach == machine || pmach == elfcpp::EM_NONE)
&& p->get_size() == size
&& (p->is_big_endian() ? is_big_endian : !is_big_endian))
{
Target* ret = p->recognize(input_file, offset,
machine, osabi, abiversion);
if (ret != NULL)
return ret;
}
}
return NULL;
}
// Find a target using a BFD name. This is used to support the
// --oformat option.
Target*
select_target_by_bfd_name(const char* name)
{
for (Target_selector* p = target_selectors; p != NULL; p = p->next())
{
const char* pname = p->bfd_name();
if (pname == NULL || strcmp(pname, name) == 0)
{
Target* ret = p->recognize_by_bfd_name(name);
if (ret != NULL)
return ret;
}
}
return NULL;
}
// Find a target using a GNU linker emulation. This is used to
// support the -m option.
Target*
select_target_by_emulation(const char* name)
{
for (Target_selector* p = target_selectors; p != NULL; p = p->next())
{
const char* pname = p->emulation();
if (pname == NULL || strcmp(pname, name) == 0)
{
Target* ret = p->recognize_by_emulation(name);
if (ret != NULL)
return ret;
}
}
return NULL;
}
// Push all the supported BFD names onto a vector.
void
supported_target_names(std::vector<const char*>* names)
{
for (Target_selector* p = target_selectors; p != NULL; p = p->next())
p->supported_bfd_names(names);
}
// Push all the supported emulations onto a vector.
void
supported_emulation_names(std::vector<const char*>* names)
{
for (Target_selector* p = target_selectors; p != NULL; p = p->next())
p->supported_emulations(names);
}
// Implement the --print-output-format option.
void
print_output_format()
{
if (!parameters->target_valid())
{
// This case arises when --print-output-format is used with no
// input files. We need to come up with the right string to
// print based on the other options. If the user specified the
// format using a --oformat option, use that. That saves each
// target from having to remember the name that was used to
// select it. In other cases, we will just have to ask the
// target.
if (parameters->options().user_set_oformat())
{
const char* bfd_name = parameters->options().oformat();
Target* target = select_target_by_bfd_name(bfd_name);
if (target != NULL)
printf("%s\n", bfd_name);
else
gold_error(_("unrecognized output format %s"), bfd_name);
return;
}
parameters_force_valid_target();
}
const Target* target = ¶meters->target();
for (Target_selector* p = target_selectors; p != NULL; p = p->next())
{
const char* bfd_name = p->target_bfd_name(target);
if (bfd_name != NULL)
{
printf("%s\n", bfd_name);
return;
}
}
gold_unreachable();
}
} // End namespace gold.
|
