1 /* BFD back-end for Intel 386 COFF files (DJGPP variant).
2 Copyright (C) 1990-2021 Free Software Foundation, Inc.
3 Written by DJ Delorie.
4
5 This file is part of BFD, the Binary File Descriptor library.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
20 MA 02110-1301, USA. */
21
22 #define TARGET_SYM i386_coff_go32_vec
23 #define TARGET_NAME "coff-go32"
24 #define TARGET_UNDERSCORE '_'
25 #define COFF_GO32
26 #define COFF_LONG_SECTION_NAMES
27 #define COFF_SUPPORT_GNU_LINKONCE
28 #define COFF_LONG_FILENAMES
29
30 #define COFF_SECTION_ALIGNMENT_ENTRIES \
31 { COFF_SECTION_NAME_EXACT_MATCH (".data"), \
32 COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \
33 { COFF_SECTION_NAME_EXACT_MATCH (".text"), \
34 COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \
35 { COFF_SECTION_NAME_PARTIAL_MATCH (".gnu.linkonce.d"), \
36 COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \
37 { COFF_SECTION_NAME_PARTIAL_MATCH (".gnu.linkonce.t"), \
38 COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \
39 { COFF_SECTION_NAME_PARTIAL_MATCH (".gnu.linkonce.r"), \
40 COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \
41 { COFF_SECTION_NAME_PARTIAL_MATCH (".debug"), \
42 COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 0 }, \
43 { COFF_SECTION_NAME_PARTIAL_MATCH (".gnu.linkonce.wi"), \
44 COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 0 }
45
46 /* Section contains extended relocations. */
47 #define IMAGE_SCN_LNK_NRELOC_OVFL (0x01000000)
48
49 #include "sysdep.h"
50 #include "bfd.h"
51
52 /* The following functions are not static, because they are also
53 used for coff-go32-exe (coff-stgo32.c). */
54 bool _bfd_go32_mkobject (bfd *);
55 void _bfd_go32_swap_scnhdr_in (bfd *, void *, void *);
56 unsigned int _bfd_go32_swap_scnhdr_out (bfd *, void *, void *);
57
58 #define coff_mkobject _bfd_go32_mkobject
59 #define coff_SWAP_scnhdr_in _bfd_go32_swap_scnhdr_in
60 #define coff_SWAP_scnhdr_out _bfd_go32_swap_scnhdr_out
61
62 #include "coff-i386.c"
63
64 bool
_bfd_go32_mkobject(bfd * abfd)65 _bfd_go32_mkobject (bfd * abfd)
66 {
67 const bfd_size_type amt = sizeof (coff_data_type);
68
69 abfd->tdata.coff_obj_data = bfd_zalloc (abfd, amt);
70 if (abfd->tdata.coff_obj_data == NULL)
71 return false;
72
73 coff_data (abfd)->go32 = true;
74
75 return true;
76 }
77
78 void
_bfd_go32_swap_scnhdr_in(bfd * abfd,void * ext,void * in)79 _bfd_go32_swap_scnhdr_in (bfd * abfd, void * ext, void * in)
80 {
81 SCNHDR *scnhdr_ext = (SCNHDR *) ext;
82 struct internal_scnhdr *scnhdr_int = (struct internal_scnhdr *) in;
83
84 memcpy (scnhdr_int->s_name, scnhdr_ext->s_name, sizeof (scnhdr_int->s_name));
85
86 scnhdr_int->s_vaddr = GET_SCNHDR_VADDR (abfd, scnhdr_ext->s_vaddr);
87 scnhdr_int->s_paddr = GET_SCNHDR_PADDR (abfd, scnhdr_ext->s_paddr);
88 scnhdr_int->s_size = GET_SCNHDR_SIZE (abfd, scnhdr_ext->s_size);
89
90 scnhdr_int->s_scnptr = GET_SCNHDR_SCNPTR (abfd, scnhdr_ext->s_scnptr);
91 scnhdr_int->s_relptr = GET_SCNHDR_RELPTR (abfd, scnhdr_ext->s_relptr);
92 scnhdr_int->s_lnnoptr = GET_SCNHDR_LNNOPTR (abfd, scnhdr_ext->s_lnnoptr);
93 scnhdr_int->s_flags = GET_SCNHDR_FLAGS (abfd, scnhdr_ext->s_flags);
94 scnhdr_int->s_nreloc = GET_SCNHDR_NRELOC (abfd, scnhdr_ext->s_nreloc);
95 scnhdr_int->s_nlnno = GET_SCNHDR_NLNNO (abfd, scnhdr_ext->s_nlnno);
96
97 /* DJGPP follows the same strategy as PE COFF.
98 Iff the file is an executable then the higher 16 bits
99 of the line number have been stored in the relocation
100 counter field. */
101 if (abfd->flags & EXEC_P && (strcmp (scnhdr_ext->s_name, ".text") == 0))
102 {
103 scnhdr_int->s_nlnno
104 = (GET_SCNHDR_NRELOC (abfd, scnhdr_ext->s_nreloc) << 16)
105 + GET_SCNHDR_NLNNO (abfd, scnhdr_ext->s_nlnno);
106 scnhdr_int->s_nreloc = 0;
107 }
108 }
109
110 unsigned int
_bfd_go32_swap_scnhdr_out(bfd * abfd,void * in,void * out)111 _bfd_go32_swap_scnhdr_out (bfd * abfd, void * in, void * out)
112 {
113 struct internal_scnhdr *scnhdr_int = (struct internal_scnhdr *) in;
114 SCNHDR *scnhdr_ext = (SCNHDR *) out;
115 unsigned int ret = bfd_coff_scnhsz (abfd);
116
117 memcpy (scnhdr_ext->s_name, scnhdr_int->s_name, sizeof (scnhdr_int->s_name));
118
119 PUT_SCNHDR_VADDR (abfd, scnhdr_int->s_vaddr, scnhdr_ext->s_vaddr);
120 PUT_SCNHDR_PADDR (abfd, scnhdr_int->s_paddr, scnhdr_ext->s_paddr);
121 PUT_SCNHDR_SIZE (abfd, scnhdr_int->s_size, scnhdr_ext->s_size);
122 PUT_SCNHDR_SCNPTR (abfd, scnhdr_int->s_scnptr, scnhdr_ext->s_scnptr);
123 PUT_SCNHDR_RELPTR (abfd, scnhdr_int->s_relptr, scnhdr_ext->s_relptr);
124 PUT_SCNHDR_LNNOPTR (abfd, scnhdr_int->s_lnnoptr, scnhdr_ext->s_lnnoptr);
125 PUT_SCNHDR_FLAGS (abfd, scnhdr_int->s_flags, scnhdr_ext->s_flags);
126
127 if (abfd->flags & EXEC_P && (strcmp (scnhdr_int->s_name, ".text") == 0))
128 {
129 /* DJGPP follows the same strategy as PE COFF.
130 By inference from looking at MS output, the 32 bit field
131 which is the combination of the number_of_relocs and
132 number_of_linenos is used for the line number count in
133 executables. A 16-bit field won't do for cc1. The MS
134 document says that the number of relocs is zero for
135 executables, but the 17-th bit has been observed to be there.
136 Overflow is not an issue: a 4G-line program will overflow a
137 bunch of other fields long before this! */
138 PUT_SCNHDR_NLNNO (abfd, (scnhdr_int->s_nlnno & 0xffff),
139 scnhdr_ext->s_nlnno);
140 PUT_SCNHDR_NRELOC (abfd, (scnhdr_int->s_nlnno >> 16),
141 scnhdr_ext->s_nreloc);
142 }
143 else
144 {
145 /* DJGPP follows the same strategy as PE COFF. */
146 if (scnhdr_int->s_nlnno <= MAX_SCNHDR_NLNNO)
147 PUT_SCNHDR_NLNNO (abfd, scnhdr_int->s_nlnno, scnhdr_ext->s_nlnno);
148 else
149 {
150 char buf[sizeof (scnhdr_int->s_name) + 1];
151
152 memcpy (buf, scnhdr_int->s_name, sizeof (scnhdr_int->s_name));
153 buf[sizeof (scnhdr_int->s_name)] = '\0';
154 _bfd_error_handler
155 /* xgettext:c-format */
156 (_("%pB: warning: %s: line number overflow: 0x%lx > 0xffff"),
157 abfd, buf, scnhdr_int->s_nlnno);
158 bfd_set_error (bfd_error_file_truncated);
159 PUT_SCNHDR_NLNNO (abfd, 0xffff, scnhdr_ext->s_nlnno);
160 ret = 0;
161 }
162
163 /* Although we could encode 0xffff relocs here, we do not, to be
164 consistent with other parts of bfd. Also it lets us warn, as
165 we should never see 0xffff here w/o having the overflow flag
166 set. */
167 if (scnhdr_int->s_nreloc < MAX_SCNHDR_NRELOC)
168 PUT_SCNHDR_NRELOC (abfd, scnhdr_int->s_nreloc, scnhdr_ext->s_nreloc);
169 else
170 {
171 /* DJGPP can deal with large #s of relocs, but not here. */
172 PUT_SCNHDR_NRELOC (abfd, 0xffff, scnhdr_ext->s_nreloc);
173 scnhdr_int->s_flags |= IMAGE_SCN_LNK_NRELOC_OVFL;
174 PUT_SCNHDR_FLAGS (abfd, scnhdr_int->s_flags, scnhdr_ext->s_flags);
175 }
176 }
177
178 return ret;
179 }
180