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. */
22 #include "gdb_string.h"
28 /* This table matches the indices assigned to enum gdb_osabi. Keep
30 static const char * const gdb_osabi_names[] =
57 gdbarch_osabi_name (enum gdb_osabi osabi)
59 if (osabi >= GDB_OSABI_UNKNOWN && osabi < GDB_OSABI_INVALID)
60 return gdb_osabi_names[osabi];
62 return gdb_osabi_names[GDB_OSABI_INVALID];
65 /* Handler for a given architecture/OS ABI pair. There should be only
66 one handler for a given OS ABI each architecture family. */
67 struct gdb_osabi_handler
69 struct gdb_osabi_handler *next;
70 enum bfd_architecture arch;
72 void (*init_osabi)(struct gdbarch_info, struct gdbarch *);
75 static struct gdb_osabi_handler *gdb_osabi_handler_list;
78 gdbarch_register_osabi (enum bfd_architecture arch, enum gdb_osabi osabi,
79 void (*init_osabi)(struct gdbarch_info,
82 struct gdb_osabi_handler **handler_p;
84 /* Registering an OS ABI handler for "unknown" is not allowed. */
85 if (osabi == GDB_OSABI_UNKNOWN)
89 "gdbarch_register_osabi: An attempt to register a handler for "
90 "OS ABI \"%s\" for architecture %s was made. The handler will "
92 gdbarch_osabi_name (osabi),
93 bfd_printable_arch_mach (arch, 0));
97 for (handler_p = &gdb_osabi_handler_list; *handler_p != NULL;
98 handler_p = &(*handler_p)->next)
100 if ((*handler_p)->arch == arch
101 && (*handler_p)->osabi == osabi)
105 "gdbarch_register_osabi: A handler for OS ABI \"%s\" "
106 "has already been registered for architecture %s",
107 gdbarch_osabi_name (osabi),
108 bfd_printable_arch_mach (arch, 0));
109 /* If user wants to continue, override previous definition. */
110 (*handler_p)->init_osabi = init_osabi;
116 = (struct gdb_osabi_handler *) xmalloc (sizeof (struct gdb_osabi_handler));
117 (*handler_p)->next = NULL;
118 (*handler_p)->arch = arch;
119 (*handler_p)->osabi = osabi;
120 (*handler_p)->init_osabi = init_osabi;
124 /* Sniffer to find the OS ABI for a given file's architecture and flavour.
125 It is legal to have multiple sniffers for each arch/flavour pair, to
126 disambiguate one OS's a.out from another, for example. The first sniffer
127 to return something other than GDB_OSABI_UNKNOWN wins, so a sniffer should
128 be careful to claim a file only if it knows for sure what it is. */
129 struct gdb_osabi_sniffer
131 struct gdb_osabi_sniffer *next;
132 enum bfd_architecture arch; /* bfd_arch_unknown == wildcard */
133 enum bfd_flavour flavour;
134 enum gdb_osabi (*sniffer)(bfd *);
137 static struct gdb_osabi_sniffer *gdb_osabi_sniffer_list;
140 gdbarch_register_osabi_sniffer (enum bfd_architecture arch,
141 enum bfd_flavour flavour,
142 enum gdb_osabi (*sniffer_fn)(bfd *))
144 struct gdb_osabi_sniffer *sniffer;
147 (struct gdb_osabi_sniffer *) xmalloc (sizeof (struct gdb_osabi_sniffer));
148 sniffer->arch = arch;
149 sniffer->flavour = flavour;
150 sniffer->sniffer = sniffer_fn;
152 sniffer->next = gdb_osabi_sniffer_list;
153 gdb_osabi_sniffer_list = sniffer;
158 gdbarch_lookup_osabi (bfd *abfd)
160 struct gdb_osabi_sniffer *sniffer;
161 enum gdb_osabi osabi, match;
164 match = GDB_OSABI_UNKNOWN;
167 for (sniffer = gdb_osabi_sniffer_list; sniffer != NULL;
168 sniffer = sniffer->next)
170 if ((sniffer->arch == bfd_arch_unknown /* wildcard */
171 || sniffer->arch == bfd_get_arch (abfd))
172 && sniffer->flavour == bfd_get_flavour (abfd))
174 osabi = (*sniffer->sniffer) (abfd);
175 if (osabi < GDB_OSABI_UNKNOWN || osabi >= GDB_OSABI_INVALID)
179 "gdbarch_lookup_osabi: invalid OS ABI (%d) from sniffer "
180 "for architecture %s flavour %d",
182 bfd_printable_arch_mach (bfd_get_arch (abfd), 0),
183 (int) bfd_get_flavour (abfd));
185 else if (osabi != GDB_OSABI_UNKNOWN)
187 /* A specific sniffer always overrides a generic sniffer.
188 Croak on multiple match if the two matches are of the
189 same class. If the user wishes to continue, we'll use
191 if (match != GDB_OSABI_UNKNOWN)
193 if ((match_specific && sniffer->arch != bfd_arch_unknown)
194 || (!match_specific && sniffer->arch == bfd_arch_unknown))
198 "gdbarch_lookup_osabi: multiple %sspecific OS ABI "
199 "match for architecture %s flavour %d: first "
200 "match \"%s\", second match \"%s\"",
201 match_specific ? "" : "non-",
202 bfd_printable_arch_mach (bfd_get_arch (abfd), 0),
203 (int) bfd_get_flavour (abfd),
204 gdbarch_osabi_name (match),
205 gdbarch_osabi_name (osabi));
207 else if (sniffer->arch != bfd_arch_unknown)
216 if (sniffer->arch != bfd_arch_unknown)
227 gdbarch_init_osabi (struct gdbarch_info info, struct gdbarch *gdbarch,
228 enum gdb_osabi osabi)
230 struct gdb_osabi_handler *handler;
231 bfd *abfd = info.abfd;
232 const struct bfd_arch_info *arch_info = gdbarch_bfd_arch_info (gdbarch);
234 if (osabi == GDB_OSABI_UNKNOWN)
236 /* Don't complain about an unknown OSABI. Assume the user knows
237 what they are doing. */
241 for (handler = gdb_osabi_handler_list; handler != NULL;
242 handler = handler->next)
244 if (handler->arch == bfd_get_arch (abfd)
245 && handler->osabi == osabi)
247 (*handler->init_osabi) (info, gdbarch);
252 /* We assume that if GDB_MULTI_ARCH is less than GDB_MULTI_ARCH_TM
253 that an ABI variant can be supported by overriding definitions in
255 if (GDB_MULTI_ARCH > GDB_MULTI_ARCH_PARTIAL)
258 "A handler for the OS ABI \"%s\" is not built into this "
259 "configuration of GDB. "
260 "Attempting to continue with the default %s settings",
261 gdbarch_osabi_name (osabi),
262 bfd_printable_arch_mach (arch_info->arch, arch_info->mach));
266 /* Generic sniffer for ELF flavoured files. */
269 generic_elf_osabi_sniff_abi_tag_sections (bfd *abfd, asection *sect, void *obj)
271 enum gdb_osabi *os_ident_ptr = obj;
273 unsigned int sectsize;
275 name = bfd_get_section_name (abfd, sect);
276 sectsize = bfd_section_size (abfd, sect);
278 /* .note.ABI-tag notes, used by GNU/Linux and FreeBSD. */
279 if (strcmp (name, ".note.ABI-tag") == 0 && sectsize > 0)
281 unsigned int name_length, data_length, note_type;
284 /* If the section is larger than this, it's probably not what we are
289 note = alloca (sectsize);
291 bfd_get_section_contents (abfd, sect, note,
292 (file_ptr) 0, (bfd_size_type) sectsize);
294 name_length = bfd_h_get_32 (abfd, note);
295 data_length = bfd_h_get_32 (abfd, note + 4);
296 note_type = bfd_h_get_32 (abfd, note + 8);
298 if (name_length == 4 && data_length == 16 && note_type == NT_GNU_ABI_TAG
299 && strcmp (note + 12, "GNU") == 0)
301 int os_number = bfd_h_get_32 (abfd, note + 16);
305 case GNU_ABI_TAG_LINUX:
306 *os_ident_ptr = GDB_OSABI_LINUX;
309 case GNU_ABI_TAG_HURD:
310 *os_ident_ptr = GDB_OSABI_HURD;
313 case GNU_ABI_TAG_SOLARIS:
314 *os_ident_ptr = GDB_OSABI_SOLARIS;
320 "generic_elf_osabi_sniff_abi_tag_sections: unknown OS number %d",
325 else if (name_length == 8 && data_length == 4
326 && note_type == NT_FREEBSD_ABI_TAG
327 && strcmp (note + 12, "FreeBSD") == 0)
329 /* XXX Should we check the version here? Probably not
331 *os_ident_ptr = GDB_OSABI_FREEBSD_ELF;
336 /* .note.netbsd.ident notes, used by NetBSD. */
337 if (strcmp (name, ".note.netbsd.ident") == 0 && sectsize > 0)
339 unsigned int name_length, data_length, note_type;
342 /* If the section is larger than this, it's probably not what we are
347 note = alloca (sectsize);
349 bfd_get_section_contents (abfd, sect, note,
350 (file_ptr) 0, (bfd_size_type) sectsize);
352 name_length = bfd_h_get_32 (abfd, note);
353 data_length = bfd_h_get_32 (abfd, note + 4);
354 note_type = bfd_h_get_32 (abfd, note + 8);
356 if (name_length == 7 && data_length == 4 && note_type == NT_NETBSD_IDENT
357 && strcmp (note + 12, "NetBSD") == 0)
359 /* XXX Should we check the version here? Probably not
361 *os_ident_ptr = GDB_OSABI_NETBSD_ELF;
367 static enum gdb_osabi
368 generic_elf_osabi_sniffer (bfd *abfd)
370 unsigned int elfosabi;
371 enum gdb_osabi osabi = GDB_OSABI_UNKNOWN;
373 elfosabi = elf_elfheader (abfd)->e_ident[EI_OSABI];
378 /* When elfosabi is ELFOSABI_NONE (0), then the ELF structures in the
379 file are conforming to the base specification for that machine
380 (there are no OS-specific extensions). In order to determine the
381 real OS in use we must look for OS notes that have been added. */
382 bfd_map_over_sections (abfd,
383 generic_elf_osabi_sniff_abi_tag_sections,
387 case ELFOSABI_FREEBSD:
388 osabi = GDB_OSABI_FREEBSD_ELF;
391 case ELFOSABI_NETBSD:
392 osabi = GDB_OSABI_NETBSD_ELF;
396 osabi = GDB_OSABI_LINUX;
400 osabi = GDB_OSABI_HURD;
403 case ELFOSABI_SOLARIS:
404 osabi = GDB_OSABI_SOLARIS;
408 if (osabi == GDB_OSABI_UNKNOWN)
410 /* The FreeBSD folks have been naughty; they stored the string
411 "FreeBSD" in the padding of the e_ident field of the ELF
412 header to "brand" their ELF binaries in FreeBSD 3.x. */
413 if (strcmp (&elf_elfheader (abfd)->e_ident[8], "FreeBSD") == 0)
414 osabi = GDB_OSABI_FREEBSD_ELF;
422 _initialize_gdb_osabi (void)
424 if (strcmp (gdb_osabi_names[GDB_OSABI_INVALID], "<invalid>") != 0)
427 "_initialize_gdb_osabi: gdb_osabi_names[] is inconsistent");
429 /* Register a generic sniffer for ELF flavoured files. */
430 gdbarch_register_osabi_sniffer (bfd_arch_unknown,
431 bfd_target_elf_flavour,
432 generic_elf_osabi_sniffer);