/* Read a symbol table in MIPS' format (Third-Eye).
- Copyright 1986, 1987, 1989, 1990, 1991, 1992, 1993 Free Software
- Foundation, Inc.
+ Copyright 1986, 1987, 1989, 1990, 1991, 1992, 1993, 1994
+ 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.
mdebugread.c. */
#include "defs.h"
+#include <string.h>
+#include "bfd.h"
#include "symtab.h"
#include "symfile.h"
#include "objfiles.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"
static void
mipscoff_new_init PARAMS ((struct objfile *));
static struct section_offsets *
mipscoff_symfile_offsets PARAMS ((struct objfile *, CORE_ADDR));
+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). */
process it and define symbols accordingly. */
if (ecoff_slurp_symbolic_info (abfd) == false)
- error ("Error reading symbol table: %s", bfd_errmsg (bfd_error));
+ 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, section_offsets);
+ /* Add the dynamic symbols if we are reading the main symbol table. */
+
+ if (mainline)
+ read_alphacoff_dynamic_symtab (section_offsets, objfile);
+
+ if (!have_partial_symbols ())
+ {
+ wrap_here ("");
+ printf_filtered ("(no debugging symbols found)...");
+ wrap_here ("");
+ }
+
/* Install any minimal symbols that have been collected as the current
minimal symbols for this objfile. */
return section_offsets;
}
+/* 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)
+ {
+ dt_mips_local_gotno = bfd_h_get_32 (abfd,
+ (bfd_byte *) x_dynp->d_un.d_val);
+ }
+ else if (dyn_tag == DT_MIPS_GOTSYM)
+ {
+ 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 (obsavestring (name,
+ strlen (name),
+ &objfile -> symbol_obstack),
+ sym_value,
+ ms_type,
+ objfile);
+ }
+}
+
/* Initialization */
static struct sym_fns ecoff_sym_fns =