bfd/
[binutils.git] / bfd / elfcore.h
blobb1cf42d79fabe233863d6466d3820e4cb717d156
1 /* ELF core file support for BFD.
2 Copyright 1995, 1996, 1997, 1998, 2000, 2001, 2002, 2003, 2005
3 Free Software Foundation, Inc.
5 This file is part of BFD, the Binary File Descriptor library.
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 2 of the License, or
10 (at your option) any later version.
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.
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, MA 02110-1301, USA. */
21 char*
22 elf_core_file_failing_command (bfd *abfd)
24 return elf_tdata (abfd)->core_command;
27 int
28 elf_core_file_failing_signal (bfd *abfd)
30 return elf_tdata (abfd)->core_signal;
33 bfd_boolean
34 elf_core_file_matches_executable_p (bfd *core_bfd, bfd *exec_bfd)
36 char* corename;
38 /* xvecs must match if both are ELF files for the same target. */
40 if (core_bfd->xvec != exec_bfd->xvec)
42 bfd_set_error (bfd_error_system_call);
43 return FALSE;
46 /* See if the name in the corefile matches the executable name. */
47 corename = elf_tdata (core_bfd)->core_program;
48 if (corename != NULL)
50 const char* execname = strrchr (exec_bfd->filename, '/');
52 execname = execname ? execname + 1 : exec_bfd->filename;
54 if (strcmp (execname, corename) != 0)
55 return FALSE;
58 return TRUE;
61 /* Core files are simply standard ELF formatted files that partition
62 the file using the execution view of the file (program header table)
63 rather than the linking view. In fact, there is no section header
64 table in a core file.
66 The process status information (including the contents of the general
67 register set) and the floating point register set are stored in a
68 segment of type PT_NOTE. We handcraft a couple of extra bfd sections
69 that allow standard bfd access to the general registers (.reg) and the
70 floating point registers (.reg2). */
72 const bfd_target *
73 elf_core_file_p (bfd *abfd)
75 Elf_External_Ehdr x_ehdr; /* Elf file header, external form. */
76 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form. */
77 Elf_Internal_Phdr *i_phdrp; /* Elf program header, internal form. */
78 unsigned int phindex;
79 const struct elf_backend_data *ebd;
80 struct bfd_preserve preserve;
81 bfd_size_type amt;
83 preserve.marker = NULL;
85 /* Read in the ELF header in external format. */
86 if (bfd_bread (&x_ehdr, sizeof (x_ehdr), abfd) != sizeof (x_ehdr))
88 if (bfd_get_error () != bfd_error_system_call)
89 goto wrong;
90 else
91 goto fail;
94 /* Check the magic number. */
95 if (! elf_file_p (&x_ehdr))
96 goto wrong;
98 /* FIXME: Check EI_VERSION here ! */
100 /* Check the address size ("class"). */
101 if (x_ehdr.e_ident[EI_CLASS] != ELFCLASS)
102 goto wrong;
104 /* Check the byteorder. */
105 switch (x_ehdr.e_ident[EI_DATA])
107 case ELFDATA2MSB: /* Big-endian. */
108 if (! bfd_big_endian (abfd))
109 goto wrong;
110 break;
111 case ELFDATA2LSB: /* Little-endian. */
112 if (! bfd_little_endian (abfd))
113 goto wrong;
114 break;
115 default:
116 goto wrong;
119 if (!bfd_preserve_save (abfd, &preserve))
120 goto fail;
122 /* Give abfd an elf_obj_tdata. */
123 if (! (*abfd->xvec->_bfd_set_format[bfd_core]) (abfd))
124 goto fail;
125 preserve.marker = elf_tdata (abfd);
127 /* Swap in the rest of the header, now that we have the byte order. */
128 i_ehdrp = elf_elfheader (abfd);
129 elf_swap_ehdr_in (abfd, &x_ehdr, i_ehdrp);
131 #if DEBUG & 1
132 elf_debug_file (i_ehdrp);
133 #endif
135 ebd = get_elf_backend_data (abfd);
137 /* Check that the ELF e_machine field matches what this particular
138 BFD format expects. */
140 if (ebd->elf_machine_code != i_ehdrp->e_machine
141 && (ebd->elf_machine_alt1 == 0
142 || i_ehdrp->e_machine != ebd->elf_machine_alt1)
143 && (ebd->elf_machine_alt2 == 0
144 || i_ehdrp->e_machine != ebd->elf_machine_alt2))
146 const bfd_target * const *target_ptr;
148 if (ebd->elf_machine_code != EM_NONE)
149 goto wrong;
151 /* This is the generic ELF target. Let it match any ELF target
152 for which we do not have a specific backend. */
154 for (target_ptr = bfd_target_vector; *target_ptr != NULL; target_ptr++)
156 const struct elf_backend_data *back;
158 if ((*target_ptr)->flavour != bfd_target_elf_flavour)
159 continue;
160 back = (const struct elf_backend_data *) (*target_ptr)->backend_data;
161 if (back->elf_machine_code == i_ehdrp->e_machine
162 || (back->elf_machine_alt1 != 0
163 && i_ehdrp->e_machine == back->elf_machine_alt1)
164 || (back->elf_machine_alt2 != 0
165 && i_ehdrp->e_machine == back->elf_machine_alt2))
167 /* target_ptr is an ELF backend which matches this
168 object file, so reject the generic ELF target. */
169 goto wrong;
174 /* If there is no program header, or the type is not a core file, then
175 we are hosed. */
176 if (i_ehdrp->e_phoff == 0 || i_ehdrp->e_type != ET_CORE)
177 goto wrong;
179 /* Does BFD's idea of the phdr size match the size
180 recorded in the file? */
181 if (i_ehdrp->e_phentsize != sizeof (Elf_External_Phdr))
182 goto wrong;
184 /* Move to the start of the program headers. */
185 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_phoff, SEEK_SET) != 0)
186 goto wrong;
188 /* Allocate space for the program headers. */
189 amt = sizeof (*i_phdrp) * i_ehdrp->e_phnum;
190 i_phdrp = bfd_alloc (abfd, amt);
191 if (!i_phdrp)
192 goto fail;
194 elf_tdata (abfd)->phdr = i_phdrp;
196 /* Read and convert to internal form. */
197 for (phindex = 0; phindex < i_ehdrp->e_phnum; ++phindex)
199 Elf_External_Phdr x_phdr;
201 if (bfd_bread (&x_phdr, sizeof (x_phdr), abfd) != sizeof (x_phdr))
202 goto fail;
204 elf_swap_phdr_in (abfd, &x_phdr, i_phdrp + phindex);
207 /* Set the machine architecture. Do this before processing the
208 program headers since we need to know the architecture type
209 when processing the notes of some systems' core files. */
210 if (! bfd_default_set_arch_mach (abfd, ebd->arch, 0)
211 /* It's OK if this fails for the generic target. */
212 && ebd->elf_machine_code != EM_NONE)
213 goto fail;
215 /* Let the backend double check the format and override global
216 information. We do this before processing the program headers
217 to allow the correct machine (as opposed to just the default
218 machine) to be set, making it possible for grok_prstatus and
219 grok_psinfo to rely on the mach setting. */
220 if (ebd->elf_backend_object_p != NULL
221 && ! ebd->elf_backend_object_p (abfd))
222 goto wrong;
224 /* Process each program header. */
225 for (phindex = 0; phindex < i_ehdrp->e_phnum; ++phindex)
226 if (! bfd_section_from_phdr (abfd, i_phdrp + phindex, (int) phindex))
227 goto fail;
229 /* Save the entry point from the ELF header. */
230 bfd_get_start_address (abfd) = i_ehdrp->e_entry;
232 bfd_preserve_finish (abfd, &preserve);
233 return abfd->xvec;
235 wrong:
236 /* There is way too much undoing of half-known state here. The caller,
237 bfd_check_format_matches, really shouldn't iterate on live bfd's to
238 check match/no-match like it does. We have to rely on that a call to
239 bfd_default_set_arch_mach with the previously known mach, undoes what
240 was done by the first bfd_default_set_arch_mach (with mach 0) here.
241 For this to work, only elf-data and the mach may be changed by the
242 target-specific elf_backend_object_p function. Note that saving the
243 whole bfd here and restoring it would be even worse; the first thing
244 you notice is that the cached bfd file position gets out of sync. */
245 bfd_set_error (bfd_error_wrong_format);
247 fail:
248 if (preserve.marker != NULL)
249 bfd_preserve_restore (abfd, &preserve);
250 return NULL;