2009-06-12 Tristan Gingold <gingold@adacore.com>
[binutils.git] / bfd / elfcore.h
blobf9d578860ecb1536dc845abeae2f570393e57ea2
1 /* ELF core file support for BFD.
2 Copyright 1995, 1996, 1997, 1998, 2000, 2001, 2002, 2003, 2005, 2007,
3 2008 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 3 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,
20 MA 02110-1301, USA. */
22 char*
23 elf_core_file_failing_command (bfd *abfd)
25 return elf_tdata (abfd)->core_command;
28 int
29 elf_core_file_failing_signal (bfd *abfd)
31 return elf_tdata (abfd)->core_signal;
34 bfd_boolean
35 elf_core_file_matches_executable_p (bfd *core_bfd, bfd *exec_bfd)
37 char* corename;
39 /* xvecs must match if both are ELF files for the same target. */
41 if (core_bfd->xvec != exec_bfd->xvec)
43 bfd_set_error (bfd_error_system_call);
44 return FALSE;
47 /* See if the name in the corefile matches the executable name. */
48 corename = elf_tdata (core_bfd)->core_program;
49 if (corename != NULL)
51 const char* execname = strrchr (exec_bfd->filename, '/');
53 execname = execname ? execname + 1 : exec_bfd->filename;
55 if (strcmp (execname, corename) != 0)
56 return FALSE;
59 return TRUE;
62 /* Core files are simply standard ELF formatted files that partition
63 the file using the execution view of the file (program header table)
64 rather than the linking view. In fact, there is no section header
65 table in a core file.
67 The process status information (including the contents of the general
68 register set) and the floating point register set are stored in a
69 segment of type PT_NOTE. We handcraft a couple of extra bfd sections
70 that allow standard bfd access to the general registers (.reg) and the
71 floating point registers (.reg2). */
73 const bfd_target *
74 elf_core_file_p (bfd *abfd)
76 Elf_External_Ehdr x_ehdr; /* Elf file header, external form. */
77 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form. */
78 Elf_Internal_Phdr *i_phdrp; /* Elf program header, internal form. */
79 unsigned int phindex;
80 const struct elf_backend_data *ebd;
81 struct bfd_preserve preserve;
82 bfd_size_type amt;
84 preserve.marker = NULL;
86 /* Read in the ELF header in external format. */
87 if (bfd_bread (&x_ehdr, sizeof (x_ehdr), abfd) != sizeof (x_ehdr))
89 if (bfd_get_error () != bfd_error_system_call)
90 goto wrong;
91 else
92 goto fail;
95 /* Check the magic number. */
96 if (! elf_file_p (&x_ehdr))
97 goto wrong;
99 /* FIXME: Check EI_VERSION here ! */
101 /* Check the address size ("class"). */
102 if (x_ehdr.e_ident[EI_CLASS] != ELFCLASS)
103 goto wrong;
105 /* Check the byteorder. */
106 switch (x_ehdr.e_ident[EI_DATA])
108 case ELFDATA2MSB: /* Big-endian. */
109 if (! bfd_big_endian (abfd))
110 goto wrong;
111 break;
112 case ELFDATA2LSB: /* Little-endian. */
113 if (! bfd_little_endian (abfd))
114 goto wrong;
115 break;
116 default:
117 goto wrong;
120 if (!bfd_preserve_save (abfd, &preserve))
121 goto fail;
123 /* Give abfd an elf_obj_tdata. */
124 if (! (*abfd->xvec->_bfd_set_format[bfd_core]) (abfd))
125 goto fail;
126 preserve.marker = elf_tdata (abfd);
128 /* Swap in the rest of the header, now that we have the byte order. */
129 i_ehdrp = elf_elfheader (abfd);
130 elf_swap_ehdr_in (abfd, &x_ehdr, i_ehdrp);
132 #if DEBUG & 1
133 elf_debug_file (i_ehdrp);
134 #endif
136 ebd = get_elf_backend_data (abfd);
138 /* Check that the ELF e_machine field matches what this particular
139 BFD format expects. */
141 if (ebd->elf_machine_code != i_ehdrp->e_machine
142 && (ebd->elf_machine_alt1 == 0
143 || i_ehdrp->e_machine != ebd->elf_machine_alt1)
144 && (ebd->elf_machine_alt2 == 0
145 || i_ehdrp->e_machine != ebd->elf_machine_alt2))
147 const bfd_target * const *target_ptr;
149 if (ebd->elf_machine_code != EM_NONE)
150 goto wrong;
152 /* This is the generic ELF target. Let it match any ELF target
153 for which we do not have a specific backend. */
155 for (target_ptr = bfd_target_vector; *target_ptr != NULL; target_ptr++)
157 const struct elf_backend_data *back;
159 if ((*target_ptr)->flavour != bfd_target_elf_flavour)
160 continue;
161 back = xvec_get_elf_backend_data (*target_ptr);
162 if (back->s->arch_size != ARCH_SIZE)
163 continue;
164 if (back->elf_machine_code == i_ehdrp->e_machine
165 || (back->elf_machine_alt1 != 0
166 && i_ehdrp->e_machine == back->elf_machine_alt1)
167 || (back->elf_machine_alt2 != 0
168 && i_ehdrp->e_machine == back->elf_machine_alt2))
170 /* target_ptr is an ELF backend which matches this
171 object file, so reject the generic ELF target. */
172 goto wrong;
177 /* If there is no program header, or the type is not a core file, then
178 we are hosed. */
179 if (i_ehdrp->e_phoff == 0 || i_ehdrp->e_type != ET_CORE)
180 goto wrong;
182 /* Does BFD's idea of the phdr size match the size
183 recorded in the file? */
184 if (i_ehdrp->e_phentsize != sizeof (Elf_External_Phdr))
185 goto wrong;
187 /* Move to the start of the program headers. */
188 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_phoff, SEEK_SET) != 0)
189 goto wrong;
191 /* Allocate space for the program headers. */
192 amt = sizeof (*i_phdrp) * i_ehdrp->e_phnum;
193 i_phdrp = bfd_alloc (abfd, amt);
194 if (!i_phdrp)
195 goto fail;
197 elf_tdata (abfd)->phdr = i_phdrp;
199 /* Read and convert to internal form. */
200 for (phindex = 0; phindex < i_ehdrp->e_phnum; ++phindex)
202 Elf_External_Phdr x_phdr;
204 if (bfd_bread (&x_phdr, sizeof (x_phdr), abfd) != sizeof (x_phdr))
205 goto fail;
207 elf_swap_phdr_in (abfd, &x_phdr, i_phdrp + phindex);
210 /* Set the machine architecture. Do this before processing the
211 program headers since we need to know the architecture type
212 when processing the notes of some systems' core files. */
213 if (! bfd_default_set_arch_mach (abfd, ebd->arch, 0)
214 /* It's OK if this fails for the generic target. */
215 && ebd->elf_machine_code != EM_NONE)
216 goto fail;
218 /* Let the backend double check the format and override global
219 information. We do this before processing the program headers
220 to allow the correct machine (as opposed to just the default
221 machine) to be set, making it possible for grok_prstatus and
222 grok_psinfo to rely on the mach setting. */
223 if (ebd->elf_backend_object_p != NULL
224 && ! ebd->elf_backend_object_p (abfd))
225 goto wrong;
227 /* Process each program header. */
228 for (phindex = 0; phindex < i_ehdrp->e_phnum; ++phindex)
229 if (! bfd_section_from_phdr (abfd, i_phdrp + phindex, (int) phindex))
230 goto fail;
232 /* Check for core truncation. */
234 bfd_size_type high = 0;
235 struct stat statbuf;
236 for (phindex = 0; phindex < i_ehdrp->e_phnum; ++phindex)
238 Elf_Internal_Phdr *p = i_phdrp + phindex;
239 if (p->p_filesz)
241 bfd_size_type current = p->p_offset + p->p_filesz;
242 if (high < current)
243 high = current;
246 if (bfd_stat (abfd, &statbuf) == 0)
248 if ((bfd_size_type) statbuf.st_size < high)
250 (*_bfd_error_handler)
251 (_("Warning: %B is truncated: expected core file "
252 "size >= %lu, found: %lu."),
253 abfd, (unsigned long) high, (unsigned long) statbuf.st_size);
258 /* Save the entry point from the ELF header. */
259 bfd_get_start_address (abfd) = i_ehdrp->e_entry;
261 bfd_preserve_finish (abfd, &preserve);
262 return abfd->xvec;
264 wrong:
265 /* There is way too much undoing of half-known state here. The caller,
266 bfd_check_format_matches, really shouldn't iterate on live bfd's to
267 check match/no-match like it does. We have to rely on that a call to
268 bfd_default_set_arch_mach with the previously known mach, undoes what
269 was done by the first bfd_default_set_arch_mach (with mach 0) here.
270 For this to work, only elf-data and the mach may be changed by the
271 target-specific elf_backend_object_p function. Note that saving the
272 whole bfd here and restoring it would be even worse; the first thing
273 you notice is that the cached bfd file position gets out of sync. */
274 bfd_set_error (bfd_error_wrong_format);
276 fail:
277 if (preserve.marker != NULL)
278 bfd_preserve_restore (abfd, &preserve);
279 return NULL;