| /* Read a symbol table in MIPS' format (Third-Eye). |
| Copyright 1986, 87, 89, 90, 91, 92, 93, 94, 95, 96, 1998 |
| Free Software Foundation, Inc. |
| Contributed by Alessandro Forin (af@cs.cmu.edu) at CMU. Major work |
| by Per Bothner, John Gilmore and Ian Lance Taylor at Cygnus Support. |
| |
| This file is part of GDB. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place - Suite 330, |
| Boston, MA 02111-1307, USA. */ |
| |
| /* Read symbols from an ECOFF file. Most of the work is done in |
| mdebugread.c. */ |
| |
| #include "defs.h" |
| #include "gdb_string.h" |
| #include "bfd.h" |
| #include "symtab.h" |
| #include "symfile.h" |
| #include "objfiles.h" |
| #include "buildsym.h" |
| #include "stabsread.h" |
| #include "gdb-stabs.h" |
| |
| #include "coff/sym.h" |
| #include "coff/internal.h" |
| #include "coff/ecoff.h" |
| #include "libcoff.h" /* Private BFD COFF information. */ |
| #include "libecoff.h" /* Private BFD ECOFF information. */ |
| #include "elf/common.h" |
| #include "elf/mips.h" |
| |
| extern void _initialize_mipsread PARAMS ((void)); |
| |
| static void |
| mipscoff_new_init PARAMS ((struct objfile *)); |
| |
| static void |
| mipscoff_symfile_init PARAMS ((struct objfile *)); |
| |
| static void |
| mipscoff_symfile_read PARAMS ((struct objfile *, int)); |
| |
| static void |
| mipscoff_symfile_finish PARAMS ((struct objfile *)); |
| |
| static void |
| read_alphacoff_dynamic_symtab PARAMS ((struct section_offsets *, |
| struct objfile * objfile)); |
| |
| /* Initialize anything that needs initializing when a completely new |
| symbol file is specified (not just adding some symbols from another |
| file, e.g. a shared library). */ |
| |
| extern CORE_ADDR sigtramp_address; |
| |
| static void |
| mipscoff_new_init (ignore) |
| struct objfile *ignore; |
| { |
| sigtramp_address = 0; |
| stabsread_new_init (); |
| buildsym_new_init (); |
| } |
| |
| /* Initialize to read a symbol file (nothing to do). */ |
| |
| static void |
| mipscoff_symfile_init (objfile) |
| struct objfile *objfile; |
| { |
| } |
| |
| /* Read a symbol file from a file. */ |
| |
| static void |
| mipscoff_symfile_read (objfile, mainline) |
| struct objfile *objfile; |
| int mainline; |
| { |
| bfd *abfd = objfile->obfd; |
| struct cleanup *back_to; |
| |
| init_minimal_symbol_collection (); |
| back_to = make_cleanup ((make_cleanup_func) discard_minimal_symbols, 0); |
| |
| /* Now that the executable file is positioned at symbol table, |
| process it and define symbols accordingly. */ |
| |
| if (!((*ecoff_backend (abfd)->debug_swap.read_debug_info) |
| (abfd, (asection *) NULL, &ecoff_data (abfd)->debug_info))) |
| error ("Error reading symbol table: %s", bfd_errmsg (bfd_get_error ())); |
| |
| mdebug_build_psymtabs (objfile, &ecoff_backend (abfd)->debug_swap, |
| &ecoff_data (abfd)->debug_info); |
| |
| /* Add alpha coff dynamic symbols. */ |
| |
| read_alphacoff_dynamic_symtab (objfile->section_offsets, objfile); |
| |
| /* Install any minimal symbols that have been collected as the current |
| minimal symbols for this objfile. */ |
| |
| install_minimal_symbols (objfile); |
| |
| /* If the entry_file bounds are still unknown after processing the |
| partial symbols, then try to set them from the minimal symbols |
| surrounding the entry_point. */ |
| |
| if (mainline |
| && objfile->ei.entry_point != INVALID_ENTRY_POINT |
| && objfile->ei.entry_file_lowpc == INVALID_ENTRY_LOWPC) |
| { |
| struct minimal_symbol *m; |
| |
| m = lookup_minimal_symbol_by_pc (objfile->ei.entry_point); |
| if (m && SYMBOL_NAME (m + 1)) |
| { |
| objfile->ei.entry_file_lowpc = SYMBOL_VALUE_ADDRESS (m); |
| objfile->ei.entry_file_highpc = SYMBOL_VALUE_ADDRESS (m + 1); |
| } |
| } |
| |
| do_cleanups (back_to); |
| } |
| |
| /* Perform any local cleanups required when we are done with a |
| particular objfile. */ |
| |
| static void |
| mipscoff_symfile_finish (objfile) |
| struct objfile *objfile; |
| { |
| } |
| |
| /* Alpha OSF/1 encapsulates the dynamic symbols in ELF format in a |
| standard coff section. The ELF format for the symbols differs from |
| the format defined in elf/external.h. It seems that a normal ELF 32 bit |
| format is used, and the representation only changes because longs are |
| 64 bit on the alpha. In addition, the handling of text/data section |
| indices for symbols is different from the ELF ABI. |
| As the BFD linker currently does not support dynamic linking on the alpha, |
| there seems to be no reason to pollute BFD with another mixture of object |
| file formats for now. */ |
| |
| /* Format of an alpha external ELF symbol. */ |
| |
| typedef struct |
| { |
| unsigned char st_name[4]; /* Symbol name, index in string tbl */ |
| unsigned char st_pad[4]; /* Pad to long word boundary */ |
| unsigned char st_value[8]; /* Value of the symbol */ |
| unsigned char st_size[4]; /* Associated symbol size */ |
| unsigned char st_info[1]; /* Type and binding attributes */ |
| unsigned char st_other[1]; /* No defined meaning, 0 */ |
| unsigned char st_shndx[2]; /* Associated section index */ |
| } |
| Elfalpha_External_Sym; |
| |
| /* Format of an alpha external ELF dynamic info structure. */ |
| |
| typedef struct |
| { |
| unsigned char d_tag[4]; /* Tag */ |
| unsigned char d_pad[4]; /* Pad to long word boundary */ |
| union |
| { |
| unsigned char d_ptr[8]; /* Pointer value */ |
| unsigned char d_val[4]; /* Integer value */ |
| } |
| d_un; |
| } |
| Elfalpha_External_Dyn; |
| |
| /* Struct to obtain the section pointers for alpha dynamic symbol info. */ |
| |
| struct alphacoff_dynsecinfo |
| { |
| asection *sym_sect; /* Section pointer for .dynsym section */ |
| asection *str_sect; /* Section pointer for .dynstr section */ |
| asection *dyninfo_sect; /* Section pointer for .dynamic section */ |
| asection *got_sect; /* Section pointer for .got section */ |
| }; |
| |
| static void |
| alphacoff_locate_sections PARAMS ((bfd *, asection *, void *)); |
| |
| /* We are called once per section from read_alphacoff_dynamic_symtab. |
| We need to examine each section we are passed, check to see |
| if it is something we are interested in processing, and |
| if so, stash away some access information for the section. */ |
| |
| static void |
| alphacoff_locate_sections (ignore_abfd, sectp, sip) |
| bfd *ignore_abfd; |
| asection *sectp; |
| PTR sip; |
| { |
| register struct alphacoff_dynsecinfo *si; |
| |
| si = (struct alphacoff_dynsecinfo *) sip; |
| |
| if (STREQ (sectp->name, ".dynsym")) |
| { |
| si->sym_sect = sectp; |
| } |
| else if (STREQ (sectp->name, ".dynstr")) |
| { |
| si->str_sect = sectp; |
| } |
| else if (STREQ (sectp->name, ".dynamic")) |
| { |
| si->dyninfo_sect = sectp; |
| } |
| else if (STREQ (sectp->name, ".got")) |
| { |
| si->got_sect = sectp; |
| } |
| } |
| |
| /* Scan an alpha dynamic symbol table for symbols of interest and |
| add them to the minimal symbol table. */ |
| |
| static void |
| read_alphacoff_dynamic_symtab (section_offsets, objfile) |
| struct section_offsets *section_offsets; |
| struct objfile *objfile; |
| { |
| bfd *abfd = objfile->obfd; |
| struct alphacoff_dynsecinfo si; |
| char *sym_secptr; |
| char *str_secptr; |
| char *dyninfo_secptr; |
| char *got_secptr; |
| bfd_size_type sym_secsize; |
| bfd_size_type str_secsize; |
| bfd_size_type dyninfo_secsize; |
| bfd_size_type got_secsize; |
| int sym_count; |
| int i; |
| int stripped; |
| Elfalpha_External_Sym *x_symp; |
| char *dyninfo_p; |
| char *dyninfo_end; |
| int got_entry_size = 8; |
| int dt_mips_local_gotno = -1; |
| int dt_mips_gotsym = -1; |
| |
| |
| /* We currently only know how to handle alpha dynamic symbols. */ |
| if (bfd_get_arch (abfd) != bfd_arch_alpha) |
| return; |
| |
| /* Locate the dynamic symbols sections and read them in. */ |
| memset ((char *) &si, 0, sizeof (si)); |
| bfd_map_over_sections (abfd, alphacoff_locate_sections, (PTR) & si); |
| if (si.sym_sect == NULL |
| || si.str_sect == NULL |
| || si.dyninfo_sect == NULL |
| || si.got_sect == NULL) |
| return; |
| |
| sym_secsize = bfd_get_section_size_before_reloc (si.sym_sect); |
| str_secsize = bfd_get_section_size_before_reloc (si.str_sect); |
| dyninfo_secsize = bfd_get_section_size_before_reloc (si.dyninfo_sect); |
| got_secsize = bfd_get_section_size_before_reloc (si.got_sect); |
| sym_secptr = alloca (sym_secsize); |
| str_secptr = alloca (str_secsize); |
| dyninfo_secptr = alloca (dyninfo_secsize); |
| got_secptr = alloca (got_secsize); |
| |
| if (!bfd_get_section_contents (abfd, si.sym_sect, sym_secptr, |
| (file_ptr) 0, sym_secsize)) |
| return; |
| if (!bfd_get_section_contents (abfd, si.str_sect, str_secptr, |
| (file_ptr) 0, str_secsize)) |
| return; |
| if (!bfd_get_section_contents (abfd, si.dyninfo_sect, dyninfo_secptr, |
| (file_ptr) 0, dyninfo_secsize)) |
| return; |
| if (!bfd_get_section_contents (abfd, si.got_sect, got_secptr, |
| (file_ptr) 0, got_secsize)) |
| return; |
| |
| /* Find the number of local GOT entries and the index for the |
| the first dynamic symbol in the GOT. */ |
| for (dyninfo_p = dyninfo_secptr, dyninfo_end = dyninfo_p + dyninfo_secsize; |
| dyninfo_p < dyninfo_end; |
| dyninfo_p += sizeof (Elfalpha_External_Dyn)) |
| { |
| Elfalpha_External_Dyn *x_dynp = (Elfalpha_External_Dyn *) dyninfo_p; |
| long dyn_tag; |
| |
| dyn_tag = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp->d_tag); |
| if (dyn_tag == DT_NULL) |
| break; |
| else if (dyn_tag == DT_MIPS_LOCAL_GOTNO) |
| { |
| if (dt_mips_local_gotno < 0) |
| dt_mips_local_gotno |
| = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp->d_un.d_val); |
| } |
| else if (dyn_tag == DT_MIPS_GOTSYM) |
| { |
| if (dt_mips_gotsym < 0) |
| dt_mips_gotsym |
| = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp->d_un.d_val); |
| } |
| } |
| if (dt_mips_local_gotno < 0 || dt_mips_gotsym < 0) |
| return; |
| |
| /* Scan all dynamic symbols and enter them into the minimal symbol table |
| if appropriate. */ |
| sym_count = sym_secsize / sizeof (Elfalpha_External_Sym); |
| stripped = (bfd_get_symcount (abfd) == 0); |
| |
| /* Skip first symbol, which is a null dummy. */ |
| for (i = 1, x_symp = (Elfalpha_External_Sym *) sym_secptr + 1; |
| i < sym_count; |
| i++, x_symp++) |
| { |
| unsigned long strx; |
| char *name; |
| bfd_vma sym_value; |
| unsigned char sym_info; |
| unsigned int sym_shndx; |
| int isglobal; |
| enum minimal_symbol_type ms_type; |
| |
| strx = bfd_h_get_32 (abfd, (bfd_byte *) x_symp->st_name); |
| if (strx >= str_secsize) |
| continue; |
| name = str_secptr + strx; |
| if (*name == '\0' || *name == '.') |
| continue; |
| |
| sym_value = bfd_h_get_64 (abfd, (bfd_byte *) x_symp->st_value); |
| sym_info = bfd_h_get_8 (abfd, (bfd_byte *) x_symp->st_info); |
| sym_shndx = bfd_h_get_16 (abfd, (bfd_byte *) x_symp->st_shndx); |
| isglobal = (ELF_ST_BIND (sym_info) == STB_GLOBAL); |
| |
| if (sym_shndx == SHN_UNDEF) |
| { |
| /* Handle undefined functions which are defined in a shared |
| library. */ |
| if (ELF_ST_TYPE (sym_info) != STT_FUNC |
| || ELF_ST_BIND (sym_info) != STB_GLOBAL) |
| continue; |
| |
| ms_type = mst_solib_trampoline; |
| |
| /* If sym_value is nonzero, it points to the shared library |
| trampoline entry, which is what we are looking for. |
| |
| If sym_value is zero, then we have to get the GOT entry |
| for the symbol. |
| If the GOT entry is nonzero, it represents the quickstart |
| address of the function and we use that as the symbol value. |
| |
| If the GOT entry is zero, the function address has to be resolved |
| by the runtime loader before the executable is started. |
| We are unable to find any meaningful address for these |
| functions in the executable file, so we skip them. */ |
| if (sym_value == 0) |
| { |
| int got_entry_offset = |
| (i - dt_mips_gotsym + dt_mips_local_gotno) * got_entry_size; |
| |
| if (got_entry_offset < 0 || got_entry_offset >= got_secsize) |
| continue; |
| sym_value = |
| bfd_h_get_64 (abfd, |
| (bfd_byte *) (got_secptr + got_entry_offset)); |
| if (sym_value == 0) |
| continue; |
| } |
| } |
| else |
| { |
| /* Symbols defined in the executable itself. We only care about |
| them if this is a stripped executable, otherwise they have |
| been retrieved from the normal symbol table already. */ |
| if (!stripped) |
| continue; |
| |
| if (sym_shndx == SHN_MIPS_TEXT) |
| { |
| if (isglobal) |
| ms_type = mst_text; |
| else |
| ms_type = mst_file_text; |
| sym_value += ANOFFSET (section_offsets, SECT_OFF_TEXT); |
| } |
| else if (sym_shndx == SHN_MIPS_DATA) |
| { |
| if (isglobal) |
| ms_type = mst_data; |
| else |
| ms_type = mst_file_data; |
| sym_value += ANOFFSET (section_offsets, SECT_OFF_DATA); |
| } |
| else if (sym_shndx == SHN_MIPS_ACOMMON) |
| { |
| if (isglobal) |
| ms_type = mst_bss; |
| else |
| ms_type = mst_file_bss; |
| sym_value += ANOFFSET (section_offsets, SECT_OFF_BSS); |
| } |
| else if (sym_shndx == SHN_ABS) |
| { |
| ms_type = mst_abs; |
| } |
| else |
| { |
| continue; |
| } |
| } |
| |
| prim_record_minimal_symbol (name, sym_value, ms_type, objfile); |
| } |
| } |
| |
| /* Initialization */ |
| |
| static struct sym_fns ecoff_sym_fns = |
| { |
| bfd_target_ecoff_flavour, |
| mipscoff_new_init, /* sym_new_init: init anything gbl to entire symtab */ |
| mipscoff_symfile_init, /* sym_init: read initial info, setup for sym_read() */ |
| mipscoff_symfile_read, /* sym_read: read a symbol file into symtab */ |
| mipscoff_symfile_finish, /* sym_finish: finished with file, cleanup */ |
| default_symfile_offsets, /* sym_offsets: dummy FIXME til implem sym reloc */ |
| NULL /* next: pointer to next struct sym_fns */ |
| }; |
| |
| void |
| _initialize_mipsread () |
| { |
| add_symtab_fns (&ecoff_sym_fns); |
| } |