1 /* OS ABI variant handling for GDB.
2 Copyright 2001, 2002 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
27 /* This table matches the indices assigned to enum gdb_osabi. Keep
29 static const char * const gdb_osabi_names[] =
56 gdbarch_osabi_name (enum gdb_osabi osabi)
58 if (osabi >= GDB_OSABI_UNKNOWN && osabi < GDB_OSABI_INVALID)
59 return gdb_osabi_names[osabi];
61 return gdb_osabi_names[GDB_OSABI_INVALID];
64 /* Handler for a given architecture/OS ABI pair. There should be only
65 one handler for a given OS ABI each architecture family. */
66 struct gdb_osabi_handler
68 struct gdb_osabi_handler *next;
69 enum bfd_architecture arch;
71 void (*init_osabi)(struct gdbarch_info, struct gdbarch *);
74 static struct gdb_osabi_handler *gdb_osabi_handler_list;
77 gdbarch_register_osabi (enum bfd_architecture arch, enum gdb_osabi osabi,
78 void (*init_osabi)(struct gdbarch_info,
81 struct gdb_osabi_handler **handler_p;
83 /* Registering an OS ABI handler for "unknown" is not allowed. */
84 if (osabi == GDB_OSABI_UNKNOWN)
88 "gdbarch_register_osabi: An attempt to register a handler for "
89 "OS ABI \"%s\" for architecture %s was made. The handler will "
91 gdbarch_osabi_name (osabi),
92 bfd_printable_arch_mach (arch, 0));
96 for (handler_p = &gdb_osabi_handler_list; *handler_p != NULL;
97 handler_p = &(*handler_p)->next)
99 if ((*handler_p)->arch == arch
100 && (*handler_p)->osabi == osabi)
104 "gdbarch_register_osabi: A handler for OS ABI \"%s\" "
105 "has already been registered for architecture %s",
106 gdbarch_osabi_name (osabi),
107 bfd_printable_arch_mach (arch, 0));
108 /* If user wants to continue, override previous definition. */
109 (*handler_p)->init_osabi = init_osabi;
115 = (struct gdb_osabi_handler *) xmalloc (sizeof (struct gdb_osabi_handler));
116 (*handler_p)->next = NULL;
117 (*handler_p)->arch = arch;
118 (*handler_p)->osabi = osabi;
119 (*handler_p)->init_osabi = init_osabi;
123 /* Sniffer to find the OS ABI for a given file's architecture and flavour.
124 It is legal to have multiple sniffers for each arch/flavour pair, to
125 disambiguate one OS's a.out from another, for example. The first sniffer
126 to return something other than GDB_OSABI_UNKNOWN wins, so a sniffer should
127 be careful to claim a file only if it knows for sure what it is. */
128 struct gdb_osabi_sniffer
130 struct gdb_osabi_sniffer *next;
131 enum bfd_architecture arch; /* bfd_arch_unknown == wildcard */
132 enum bfd_flavour flavour;
133 enum gdb_osabi (*sniffer)(bfd *);
136 static struct gdb_osabi_sniffer *gdb_osabi_sniffer_list;
139 gdbarch_register_osabi_sniffer (enum bfd_architecture arch,
140 enum bfd_flavour flavour,
141 enum gdb_osabi (*sniffer_fn)(bfd *))
143 struct gdb_osabi_sniffer *sniffer;
146 (struct gdb_osabi_sniffer *) xmalloc (sizeof (struct gdb_osabi_sniffer));
147 sniffer->arch = arch;
148 sniffer->flavour = flavour;
149 sniffer->sniffer = sniffer_fn;
151 sniffer->next = gdb_osabi_sniffer_list;
152 gdb_osabi_sniffer_list = sniffer;
157 gdbarch_lookup_osabi (bfd *abfd)
159 struct gdb_osabi_sniffer *sniffer;
160 enum gdb_osabi osabi, match;
163 match = GDB_OSABI_UNKNOWN;
166 for (sniffer = gdb_osabi_sniffer_list; sniffer != NULL;
167 sniffer = sniffer->next)
169 if ((sniffer->arch == bfd_arch_unknown /* wildcard */
170 || sniffer->arch == bfd_get_arch (abfd))
171 && sniffer->flavour == bfd_get_flavour (abfd))
173 osabi = (*sniffer->sniffer) (abfd);
174 if (osabi < GDB_OSABI_UNKNOWN || osabi >= GDB_OSABI_INVALID)
178 "gdbarch_lookup_osabi: invalid OS ABI (%d) from sniffer "
179 "for architecture %s flavour %d",
181 bfd_printable_arch_mach (bfd_get_arch (abfd), 0),
182 (int) bfd_get_flavour (abfd));
184 else if (osabi != GDB_OSABI_UNKNOWN)
186 /* A specific sniffer always overrides a generic sniffer.
187 Croak on multiple match if the two matches are of the
188 same class. If the user wishes to continue, we'll use
190 if (match != GDB_OSABI_UNKNOWN)
192 if ((match_specific && sniffer->arch != bfd_arch_unknown)
193 || (!match_specific && sniffer->arch == bfd_arch_unknown))
197 "gdbarch_lookup_osabi: multiple %sspecific OS ABI "
198 "match for architecture %s flavour %d: first "
199 "match \"%s\", second match \"%s\"",
200 match_specific ? "" : "non-",
201 bfd_printable_arch_mach (bfd_get_arch (abfd), 0),
202 (int) bfd_get_flavour (abfd),
203 gdbarch_osabi_name (match),
204 gdbarch_osabi_name (osabi));
206 else if (sniffer->arch != bfd_arch_unknown)
215 if (sniffer->arch != bfd_arch_unknown)
226 gdbarch_init_osabi (struct gdbarch_info info, struct gdbarch *gdbarch,
227 enum gdb_osabi osabi)
229 struct gdb_osabi_handler *handler;
230 bfd *abfd = info.abfd;
231 const struct bfd_arch_info *arch_info = gdbarch_bfd_arch_info (gdbarch);
233 if (osabi == GDB_OSABI_UNKNOWN)
235 /* Don't complain about not knowing the OS ABI if we don't
239 (gdb_stderr, "GDB doesn't recognize the OS ABI of the inferior. "
240 "Attempting to continue with the default %s settings",
241 bfd_printable_arch_mach (arch_info->arch, arch_info->mach));
245 for (handler = gdb_osabi_handler_list; handler != NULL;
246 handler = handler->next)
248 if (handler->arch == bfd_get_arch (abfd)
249 && handler->osabi == osabi)
251 (*handler->init_osabi) (info, gdbarch);
256 /* We assume that if GDB_MULTI_ARCH is less than GDB_MULTI_ARCH_TM
257 that an ABI variant can be supported by overriding definitions in
259 if (GDB_MULTI_ARCH > GDB_MULTI_ARCH_PARTIAL)
262 "A handler for the OS ABI \"%s\" is not built into this "
263 "configuration of GDB. "
264 "Attempting to continue with the default %s settings",
265 gdbarch_osabi_name (osabi),
266 bfd_printable_arch_mach (arch_info->arch, arch_info->mach));
270 /* Generic sniffer for ELF flavoured files. */
273 generic_elf_osabi_sniff_abi_tag_sections (bfd *abfd, asection *sect, void *obj)
275 enum gdb_osabi *os_ident_ptr = obj;
277 unsigned int sectsize;
279 name = bfd_get_section_name (abfd, sect);
280 sectsize = bfd_section_size (abfd, sect);
282 /* .note.ABI-tag notes, used by GNU/Linux and FreeBSD. */
283 if (strcmp (name, ".note.ABI-tag") == 0 && sectsize > 0)
285 unsigned int name_length, data_length, note_type;
288 /* If the section is larger than this, it's probably not what we are
293 note = alloca (sectsize);
295 bfd_get_section_contents (abfd, sect, note,
296 (file_ptr) 0, (bfd_size_type) sectsize);
298 name_length = bfd_h_get_32 (abfd, note);
299 data_length = bfd_h_get_32 (abfd, note + 4);
300 note_type = bfd_h_get_32 (abfd, note + 8);
302 if (name_length == 4 && data_length == 16 && note_type == NT_GNU_ABI_TAG
303 && strcmp (note + 12, "GNU") == 0)
305 int os_number = bfd_h_get_32 (abfd, note + 16);
309 case GNU_ABI_TAG_LINUX:
310 *os_ident_ptr = GDB_OSABI_LINUX;
313 case GNU_ABI_TAG_HURD:
314 *os_ident_ptr = GDB_OSABI_HURD;
317 case GNU_ABI_TAG_SOLARIS:
318 *os_ident_ptr = GDB_OSABI_SOLARIS;
324 "generic_elf_osabi_sniff_abi_tag_sections: unknown OS number %d",
329 else if (name_length == 8 && data_length == 4
330 && note_type == NT_FREEBSD_ABI_TAG
331 && strcmp (note + 12, "FreeBSD") == 0)
333 /* XXX Should we check the version here? Probably not
335 *os_ident_ptr = GDB_OSABI_FREEBSD_ELF;
340 /* .note.netbsd.ident notes, used by NetBSD. */
341 if (strcmp (name, ".note.netbsd.ident") == 0 && sectsize > 0)
343 unsigned int name_length, data_length, note_type;
346 /* If the section is larger than this, it's probably not what we are
351 note = alloca (sectsize);
353 bfd_get_section_contents (abfd, sect, note,
354 (file_ptr) 0, (bfd_size_type) sectsize);
356 name_length = bfd_h_get_32 (abfd, note);
357 data_length = bfd_h_get_32 (abfd, note + 4);
358 note_type = bfd_h_get_32 (abfd, note + 8);
360 if (name_length == 7 && data_length == 4 && note_type == NT_NETBSD_IDENT
361 && strcmp (note + 12, "NetBSD") == 0)
363 /* XXX Should we check the version here? Probably not
365 *os_ident_ptr = GDB_OSABI_NETBSD_ELF;
371 static enum gdb_osabi
372 generic_elf_osabi_sniffer (bfd *abfd)
374 unsigned int elfosabi;
375 enum gdb_osabi osabi = GDB_OSABI_UNKNOWN;
377 elfosabi = elf_elfheader (abfd)->e_ident[EI_OSABI];
382 /* When elfosabi is ELFOSABI_NONE (0), then the ELF structures in the
383 file are conforming to the base specification for that machine
384 (there are no OS-specific extensions). In order to determine the
385 real OS in use we must look for OS notes that have been added. */
386 bfd_map_over_sections (abfd,
387 generic_elf_osabi_sniff_abi_tag_sections,
391 case ELFOSABI_FREEBSD:
392 osabi = GDB_OSABI_FREEBSD_ELF;
395 case ELFOSABI_NETBSD:
396 osabi = GDB_OSABI_NETBSD_ELF;
400 osabi = GDB_OSABI_LINUX;
404 osabi = GDB_OSABI_HURD;
407 case ELFOSABI_SOLARIS:
408 osabi = GDB_OSABI_SOLARIS;
412 if (osabi == GDB_OSABI_UNKNOWN)
414 /* The FreeBSD folks have been naughty; they stored the string
415 "FreeBSD" in the padding of the e_ident field of the ELF
416 header to "brand" their ELF binaries in FreeBSD 3.x. */
417 if (strcmp (&elf_elfheader (abfd)->e_ident[8], "FreeBSD") == 0)
418 osabi = GDB_OSABI_FREEBSD_ELF;
426 _initialize_gdb_osabi (void)
428 if (strcmp (gdb_osabi_names[GDB_OSABI_INVALID], "<invalid>") != 0)
431 "_initialize_gdb_osabi: gdb_osabi_names[] is inconsistent");
433 /* Register a generic sniffer for ELF flavoured files. */
434 gdbarch_register_osabi_sniffer (bfd_arch_unknown,
435 bfd_target_elf_flavour,
436 generic_elf_osabi_sniffer);