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[] =
58 gdbarch_osabi_name (enum gdb_osabi osabi)
60 if (osabi >= GDB_OSABI_UNKNOWN && osabi < GDB_OSABI_INVALID)
61 return gdb_osabi_names[osabi];
63 return gdb_osabi_names[GDB_OSABI_INVALID];
66 /* Handler for a given architecture/OS ABI pair. There should be only
67 one handler for a given OS ABI each architecture family. */
68 struct gdb_osabi_handler
70 struct gdb_osabi_handler *next;
71 enum bfd_architecture arch;
73 void (*init_osabi)(struct gdbarch_info, struct gdbarch *);
76 static struct gdb_osabi_handler *gdb_osabi_handler_list;
79 gdbarch_register_osabi (enum bfd_architecture arch, enum gdb_osabi osabi,
80 void (*init_osabi)(struct gdbarch_info,
83 struct gdb_osabi_handler **handler_p;
85 /* Registering an OS ABI handler for "unknown" is not allowed. */
86 if (osabi == GDB_OSABI_UNKNOWN)
90 "gdbarch_register_osabi: An attempt to register a handler for "
91 "OS ABI \"%s\" for architecture %s was made. The handler will "
93 gdbarch_osabi_name (osabi),
94 bfd_printable_arch_mach (arch, 0));
98 for (handler_p = &gdb_osabi_handler_list; *handler_p != NULL;
99 handler_p = &(*handler_p)->next)
101 if ((*handler_p)->arch == arch
102 && (*handler_p)->osabi == osabi)
106 "gdbarch_register_osabi: A handler for OS ABI \"%s\" "
107 "has already been registered for architecture %s",
108 gdbarch_osabi_name (osabi),
109 bfd_printable_arch_mach (arch, 0));
110 /* If user wants to continue, override previous definition. */
111 (*handler_p)->init_osabi = init_osabi;
117 = (struct gdb_osabi_handler *) xmalloc (sizeof (struct gdb_osabi_handler));
118 (*handler_p)->next = NULL;
119 (*handler_p)->arch = arch;
120 (*handler_p)->osabi = osabi;
121 (*handler_p)->init_osabi = init_osabi;
125 /* Sniffer to find the OS ABI for a given file's architecture and flavour.
126 It is legal to have multiple sniffers for each arch/flavour pair, to
127 disambiguate one OS's a.out from another, for example. The first sniffer
128 to return something other than GDB_OSABI_UNKNOWN wins, so a sniffer should
129 be careful to claim a file only if it knows for sure what it is. */
130 struct gdb_osabi_sniffer
132 struct gdb_osabi_sniffer *next;
133 enum bfd_architecture arch; /* bfd_arch_unknown == wildcard */
134 enum bfd_flavour flavour;
135 enum gdb_osabi (*sniffer)(bfd *);
138 static struct gdb_osabi_sniffer *gdb_osabi_sniffer_list;
141 gdbarch_register_osabi_sniffer (enum bfd_architecture arch,
142 enum bfd_flavour flavour,
143 enum gdb_osabi (*sniffer_fn)(bfd *))
145 struct gdb_osabi_sniffer *sniffer;
148 (struct gdb_osabi_sniffer *) xmalloc (sizeof (struct gdb_osabi_sniffer));
149 sniffer->arch = arch;
150 sniffer->flavour = flavour;
151 sniffer->sniffer = sniffer_fn;
153 sniffer->next = gdb_osabi_sniffer_list;
154 gdb_osabi_sniffer_list = sniffer;
159 gdbarch_lookup_osabi (bfd *abfd)
161 struct gdb_osabi_sniffer *sniffer;
162 enum gdb_osabi osabi, match;
165 match = GDB_OSABI_UNKNOWN;
168 for (sniffer = gdb_osabi_sniffer_list; sniffer != NULL;
169 sniffer = sniffer->next)
171 if ((sniffer->arch == bfd_arch_unknown /* wildcard */
172 || sniffer->arch == bfd_get_arch (abfd))
173 && sniffer->flavour == bfd_get_flavour (abfd))
175 osabi = (*sniffer->sniffer) (abfd);
176 if (osabi < GDB_OSABI_UNKNOWN || osabi >= GDB_OSABI_INVALID)
180 "gdbarch_lookup_osabi: invalid OS ABI (%d) from sniffer "
181 "for architecture %s flavour %d",
183 bfd_printable_arch_mach (bfd_get_arch (abfd), 0),
184 (int) bfd_get_flavour (abfd));
186 else if (osabi != GDB_OSABI_UNKNOWN)
188 /* A specific sniffer always overrides a generic sniffer.
189 Croak on multiple match if the two matches are of the
190 same class. If the user wishes to continue, we'll use
192 if (match != GDB_OSABI_UNKNOWN)
194 if ((match_specific && sniffer->arch != bfd_arch_unknown)
195 || (!match_specific && sniffer->arch == bfd_arch_unknown))
199 "gdbarch_lookup_osabi: multiple %sspecific OS ABI "
200 "match for architecture %s flavour %d: first "
201 "match \"%s\", second match \"%s\"",
202 match_specific ? "" : "non-",
203 bfd_printable_arch_mach (bfd_get_arch (abfd), 0),
204 (int) bfd_get_flavour (abfd),
205 gdbarch_osabi_name (match),
206 gdbarch_osabi_name (osabi));
208 else if (sniffer->arch != bfd_arch_unknown)
217 if (sniffer->arch != bfd_arch_unknown)
228 gdbarch_init_osabi (struct gdbarch_info info, struct gdbarch *gdbarch,
229 enum gdb_osabi osabi)
231 struct gdb_osabi_handler *handler;
232 bfd *abfd = info.abfd;
233 const struct bfd_arch_info *arch_info = gdbarch_bfd_arch_info (gdbarch);
235 if (osabi == GDB_OSABI_UNKNOWN)
237 /* Don't complain about an unknown OSABI. Assume the user knows
238 what they are doing. */
242 for (handler = gdb_osabi_handler_list; handler != NULL;
243 handler = handler->next)
245 if (handler->arch == bfd_get_arch (abfd)
246 && handler->osabi == osabi)
248 (*handler->init_osabi) (info, gdbarch);
253 /* We assume that if GDB_MULTI_ARCH is less than GDB_MULTI_ARCH_TM
254 that an ABI variant can be supported by overriding definitions in
256 if (GDB_MULTI_ARCH > GDB_MULTI_ARCH_PARTIAL)
259 "A handler for the OS ABI \"%s\" is not built into this "
260 "configuration of GDB. "
261 "Attempting to continue with the default %s settings",
262 gdbarch_osabi_name (osabi),
263 bfd_printable_arch_mach (arch_info->arch, arch_info->mach));
267 /* Generic sniffer for ELF flavoured files. */
270 generic_elf_osabi_sniff_abi_tag_sections (bfd *abfd, asection *sect, void *obj)
272 enum gdb_osabi *os_ident_ptr = obj;
274 unsigned int sectsize;
276 name = bfd_get_section_name (abfd, sect);
277 sectsize = bfd_section_size (abfd, sect);
279 /* .note.ABI-tag notes, used by GNU/Linux and FreeBSD. */
280 if (strcmp (name, ".note.ABI-tag") == 0 && sectsize > 0)
282 unsigned int name_length, data_length, note_type;
285 /* If the section is larger than this, it's probably not what we are
290 note = alloca (sectsize);
292 bfd_get_section_contents (abfd, sect, note,
293 (file_ptr) 0, (bfd_size_type) sectsize);
295 name_length = bfd_h_get_32 (abfd, note);
296 data_length = bfd_h_get_32 (abfd, note + 4);
297 note_type = bfd_h_get_32 (abfd, note + 8);
299 if (name_length == 4 && data_length == 16 && note_type == NT_GNU_ABI_TAG
300 && strcmp (note + 12, "GNU") == 0)
302 int os_number = bfd_h_get_32 (abfd, note + 16);
306 case GNU_ABI_TAG_LINUX:
307 *os_ident_ptr = GDB_OSABI_LINUX;
310 case GNU_ABI_TAG_HURD:
311 *os_ident_ptr = GDB_OSABI_HURD;
314 case GNU_ABI_TAG_SOLARIS:
315 *os_ident_ptr = GDB_OSABI_SOLARIS;
321 "generic_elf_osabi_sniff_abi_tag_sections: unknown OS number %d",
326 else if (name_length == 8 && data_length == 4
327 && note_type == NT_FREEBSD_ABI_TAG
328 && strcmp (note + 12, "FreeBSD") == 0)
330 /* XXX Should we check the version here? Probably not
332 *os_ident_ptr = GDB_OSABI_FREEBSD_ELF;
337 /* .note.netbsd.ident notes, used by NetBSD. */
338 if (strcmp (name, ".note.netbsd.ident") == 0 && sectsize > 0)
340 unsigned int name_length, data_length, note_type;
343 /* If the section is larger than this, it's probably not what we are
348 note = alloca (sectsize);
350 bfd_get_section_contents (abfd, sect, note,
351 (file_ptr) 0, (bfd_size_type) sectsize);
353 name_length = bfd_h_get_32 (abfd, note);
354 data_length = bfd_h_get_32 (abfd, note + 4);
355 note_type = bfd_h_get_32 (abfd, note + 8);
357 if (name_length == 7 && data_length == 4 && note_type == NT_NETBSD_IDENT
358 && strcmp (note + 12, "NetBSD") == 0)
360 /* XXX Should we check the version here? Probably not
362 *os_ident_ptr = GDB_OSABI_NETBSD_ELF;
368 static enum gdb_osabi
369 generic_elf_osabi_sniffer (bfd *abfd)
371 unsigned int elfosabi;
372 enum gdb_osabi osabi = GDB_OSABI_UNKNOWN;
374 elfosabi = elf_elfheader (abfd)->e_ident[EI_OSABI];
379 /* When elfosabi is ELFOSABI_NONE (0), then the ELF structures in the
380 file are conforming to the base specification for that machine
381 (there are no OS-specific extensions). In order to determine the
382 real OS in use we must look for OS notes that have been added. */
383 bfd_map_over_sections (abfd,
384 generic_elf_osabi_sniff_abi_tag_sections,
388 case ELFOSABI_FREEBSD:
389 osabi = GDB_OSABI_FREEBSD_ELF;
392 case ELFOSABI_NETBSD:
393 osabi = GDB_OSABI_NETBSD_ELF;
397 osabi = GDB_OSABI_LINUX;
401 osabi = GDB_OSABI_HURD;
404 case ELFOSABI_SOLARIS:
405 osabi = GDB_OSABI_SOLARIS;
409 if (osabi == GDB_OSABI_UNKNOWN)
411 /* The FreeBSD folks have been naughty; they stored the string
412 "FreeBSD" in the padding of the e_ident field of the ELF
413 header to "brand" their ELF binaries in FreeBSD 3.x. */
414 if (strcmp (&elf_elfheader (abfd)->e_ident[8], "FreeBSD") == 0)
415 osabi = GDB_OSABI_FREEBSD_ELF;
423 _initialize_gdb_osabi (void)
425 if (strcmp (gdb_osabi_names[GDB_OSABI_INVALID], "<invalid>") != 0)
428 "_initialize_gdb_osabi: gdb_osabi_names[] is inconsistent");
430 /* Register a generic sniffer for ELF flavoured files. */
431 gdbarch_register_osabi_sniffer (bfd_arch_unknown,
432 bfd_target_elf_flavour,
433 generic_elf_osabi_sniffer);