Initial revision

1 files changed, 803 insertions, 0 deletions

diff --git a/gdb/somread.c b/gdb/somread.c
new file mode 100644
index 00000000000..c03abd01832
--- /dev/null
+++ b/gdb/somread.c
@@ -0,0 +1,803 @@
+/* Read HP PA/Risc object files for GDB.
+   Copyright 1991, 1992, 1996 Free Software Foundation, Inc.
+   Written by Fred Fish 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.  */
+
+#include "defs.h"
+#include "bfd.h"
+#include <syms.h>
+#include "symtab.h"
+#include "symfile.h"
+#include "objfiles.h"
+#include "buildsym.h"
+#include "stabsread.h"
+#include "gdb-stabs.h"
+#include "complaints.h"
+#include "gdb_string.h"
+#include "demangle.h"
+#include "som.h"
+#include "libhppa.h"
+
+/* Various things we might complain about... */
+
+static void
+som_symfile_init PARAMS ((struct objfile *));
+
+static void
+som_new_init PARAMS ((struct objfile *));
+
+static void
+som_symfile_read PARAMS ((struct objfile *, struct section_offsets *, int));
+
+static void
+som_symfile_finish PARAMS ((struct objfile *));
+
+static void
+som_symtab_read PARAMS ((bfd *, struct objfile *,
+			 struct section_offsets *));
+
+static struct section_offsets *
+som_symfile_offsets PARAMS ((struct objfile *, CORE_ADDR));
+
+/* FIXME: These should really be in a common header somewhere */
+
+extern void
+hpread_build_psymtabs PARAMS ((struct objfile *, struct section_offsets *, int));
+
+extern void
+hpread_symfile_finish PARAMS ((struct objfile *));
+
+extern void
+hpread_symfile_init PARAMS ((struct objfile *));
+
+extern void
+do_pxdb PARAMS ((bfd *));
+
+/*
+
+LOCAL FUNCTION
+
+	som_symtab_read -- read the symbol table of a SOM file
+
+SYNOPSIS
+
+	void som_symtab_read (bfd *abfd, struct objfile *objfile,
+			      struct section_offsets *section_offsets)
+
+DESCRIPTION
+
+	Given an open bfd, a base address to relocate symbols to, and a
+	flag that specifies whether or not this bfd is for an executable
+	or not (may be shared library for example), add all the global
+	function and data symbols to the minimal symbol table.
+*/
+
+static void
+som_symtab_read (abfd, objfile, section_offsets)
+     bfd *abfd;
+     struct objfile *objfile;
+     struct section_offsets *section_offsets;
+{
+  unsigned int number_of_symbols;
+  int val, dynamic;
+  char *stringtab;
+  asection *shlib_info;
+  struct symbol_dictionary_record *buf, *bufp, *endbufp;
+  char *symname;
+  CONST int symsize = sizeof (struct symbol_dictionary_record);
+  CORE_ADDR text_offset, data_offset;
+
+
+  text_offset = ANOFFSET (section_offsets, 0);
+  data_offset = ANOFFSET (section_offsets, 1);
+
+  number_of_symbols = bfd_get_symcount (abfd);
+
+  buf = alloca (symsize * number_of_symbols);
+  bfd_seek (abfd, obj_som_sym_filepos (abfd), SEEK_SET);
+  val = bfd_read (buf, symsize * number_of_symbols, 1, abfd);
+  if (val != symsize * number_of_symbols)
+    error ("Couldn't read symbol dictionary!");
+
+  stringtab = alloca (obj_som_stringtab_size (abfd));
+  bfd_seek (abfd, obj_som_str_filepos (abfd), SEEK_SET);
+  val = bfd_read (stringtab, obj_som_stringtab_size (abfd), 1, abfd);
+  if (val != obj_som_stringtab_size (abfd))
+    error ("Can't read in HP string table.");
+
+  /* We need to determine if objfile is a dynamic executable (so we
+     can do the right thing for ST_ENTRY vs ST_CODE symbols).
+
+     There's nothing in the header which easily allows us to do
+     this.  The only reliable way I know of is to check for the
+     existance of a $SHLIB_INFO$ section with a non-zero size.  */
+  /* The code below is not a reliable way to check whether an
+   * executable is dynamic, so I commented it out - RT
+   * shlib_info = bfd_get_section_by_name (objfile->obfd, "$SHLIB_INFO$");
+   * if (shlib_info)
+   *   dynamic = (bfd_section_size (objfile->obfd, shlib_info) != 0);
+   * else
+   *   dynamic = 0;
+   */
+  /* I replaced the code with a simple check for text offset not being
+   * zero. Still not 100% reliable, but a more reliable way of asking
+   * "is this a dynamic executable?" than the above. RT
+   */
+  dynamic = (text_offset != 0);
+
+  endbufp = buf + number_of_symbols;
+  for (bufp = buf; bufp < endbufp; ++bufp)
+    {
+      enum minimal_symbol_type ms_type;
+
+      QUIT;
+
+      switch (bufp->symbol_scope)
+	{
+	case SS_UNIVERSAL:
+	case SS_EXTERNAL:
+	  switch (bufp->symbol_type)
+	    {
+	    case ST_SYM_EXT:
+	    case ST_ARG_EXT:
+	      continue;
+
+	    case ST_CODE:
+	    case ST_PRI_PROG:
+	    case ST_SEC_PROG:
+	    case ST_MILLICODE:
+	      symname = bufp->name.n_strx + stringtab;
+	      ms_type = mst_text;
+	      bufp->symbol_value += text_offset;
+#ifdef SMASH_TEXT_ADDRESS
+	      SMASH_TEXT_ADDRESS (bufp->symbol_value);
+#endif
+	      break;
+
+	    case ST_ENTRY:
+	      symname = bufp->name.n_strx + stringtab;
+	      /* For a dynamic executable, ST_ENTRY symbols are
+		 the stubs, while the ST_CODE symbol is the real
+		 function.  */
+	      if (dynamic)
+		ms_type = mst_solib_trampoline;
+	      else
+		ms_type = mst_text;
+	      bufp->symbol_value += text_offset;
+#ifdef SMASH_TEXT_ADDRESS
+	      SMASH_TEXT_ADDRESS (bufp->symbol_value);
+#endif
+	      break;
+
+	    case ST_STUB:
+	      symname = bufp->name.n_strx + stringtab;
+	      ms_type = mst_solib_trampoline;
+	      bufp->symbol_value += text_offset;
+#ifdef SMASH_TEXT_ADDRESS
+	      SMASH_TEXT_ADDRESS (bufp->symbol_value);
+#endif
+	      break;
+
+	    case ST_DATA:
+	      symname = bufp->name.n_strx + stringtab;
+	      bufp->symbol_value += data_offset;
+	      ms_type = mst_data;
+	      break;
+	    default:
+	      continue;
+	    }
+	  break;
+
+#if 0
+	  /* SS_GLOBAL and SS_LOCAL are two names for the same thing (!).  */
+	case SS_GLOBAL:
+#endif
+	case SS_LOCAL:
+	  switch (bufp->symbol_type)
+	    {
+	    case ST_SYM_EXT:
+	    case ST_ARG_EXT:
+	      continue;
+
+	    case ST_CODE:
+	      symname = bufp->name.n_strx + stringtab;
+	      ms_type = mst_file_text;
+	      bufp->symbol_value += text_offset;
+#ifdef SMASH_TEXT_ADDRESS
+	      SMASH_TEXT_ADDRESS (bufp->symbol_value);
+#endif
+
+	    check_strange_names:
+	      /* Utah GCC 2.5, FSF GCC 2.6 and later generate correct local
+		 label prefixes for stabs, constant data, etc.  So we need
+		 only filter out L$ symbols which are left in due to
+		 limitations in how GAS generates SOM relocations.
+
+		 When linking in the HPUX C-library the HP linker has
+		 the nasty habit of placing section symbols from the literal
+		 subspaces in the middle of the program's text.  Filter
+		 those out as best we can.  Check for first and last character
+		 being '$'. 
+
+		 And finally, the newer HP compilers emit crud like $PIC_foo$N
+		 in some circumstance (PIC code I guess).  It's also claimed
+		 that they emit D$ symbols too.  What stupidity.  */
+	      if ((symname[0] == 'L' && symname[1] == '$')
+		  || (symname[0] == '$' && symname[strlen(symname) - 1] == '$')
+		  || (symname[0] == 'D' && symname[1] == '$')
+		  || (strncmp (symname, "$PIC", 4) == 0))
+		continue;
+	      break;
+
+	    case ST_PRI_PROG:
+	    case ST_SEC_PROG:
+	    case ST_MILLICODE:
+	      symname = bufp->name.n_strx + stringtab;
+	      ms_type = mst_file_text;
+	      bufp->symbol_value += text_offset;
+#ifdef SMASH_TEXT_ADDRESS
+	      SMASH_TEXT_ADDRESS (bufp->symbol_value);
+#endif
+	      break;
+
+	    case ST_ENTRY:
+	      symname = bufp->name.n_strx + stringtab;
+	      /* For a dynamic executable, ST_ENTRY symbols are
+		 the stubs, while the ST_CODE symbol is the real
+		 function.  */
+	      if (dynamic)
+		ms_type = mst_solib_trampoline;
+	      else
+		ms_type = mst_file_text;
+	      bufp->symbol_value += text_offset;
+#ifdef SMASH_TEXT_ADDRESS
+	      SMASH_TEXT_ADDRESS (bufp->symbol_value);
+#endif
+	      break;
+
+	    case ST_STUB:
+	      symname = bufp->name.n_strx + stringtab;
+	      ms_type = mst_solib_trampoline;
+	      bufp->symbol_value += text_offset;
+#ifdef SMASH_TEXT_ADDRESS
+	      SMASH_TEXT_ADDRESS (bufp->symbol_value);
+#endif
+	      break;
+
+
+	    case ST_DATA:
+	      symname = bufp->name.n_strx + stringtab;
+	      bufp->symbol_value += data_offset;
+	      ms_type = mst_file_data;
+	      goto check_strange_names;
+
+	    default:
+	      continue;
+	    }
+	  break;
+
+	/* This can happen for common symbols when -E is passed to the
+	   final link.  No idea _why_ that would make the linker force
+	   common symbols to have an SS_UNSAT scope, but it does.
+
+	   This also happens for weak symbols, but their type is
+	   ST_DATA.  */
+	case SS_UNSAT:
+	  switch (bufp->symbol_type)
+	    {
+	      case ST_STORAGE:
+	      case ST_DATA:
+		symname = bufp->name.n_strx + stringtab;
+		bufp->symbol_value += data_offset;
+		ms_type = mst_data;
+		break;
+
+	      default:
+		continue;
+	    }
+	  break;
+
+	default:
+	  continue;
+	}
+
+      if (bufp->name.n_strx > obj_som_stringtab_size (abfd))
+	error ("Invalid symbol data; bad HP string table offset: %d",
+	       bufp->name.n_strx);
+
+      prim_record_minimal_symbol (symname, bufp->symbol_value, ms_type, 
+				  objfile);
+    }
+}
+
+/* Scan and build partial symbols for a symbol file.
+   We have been initialized by a call to som_symfile_init, which 
+   currently does nothing.
+
+   SECTION_OFFSETS is a set of offsets to apply to relocate the symbols
+   in each section.  This is ignored, as it isn't needed for SOM.
+
+   MAINLINE is true if we are reading the main symbol
+   table (as opposed to a shared lib or dynamically loaded file).
+
+   This function only does the minimum work necessary for letting the
+   user "name" things symbolically; it does not read the entire symtab.
+   Instead, it reads the external and static symbols and puts them in partial
+   symbol tables.  When more extensive information is requested of a
+   file, the corresponding partial symbol table is mutated into a full
+   fledged symbol table by going back and reading the symbols
+   for real.
+
+   We look for sections with specific names, to tell us what debug
+   format to look for:  FIXME!!!
+
+   somstab_build_psymtabs() handles STABS symbols.
+
+   Note that SOM files have a "minimal" symbol table, which is vaguely
+   reminiscent of a COFF symbol table, but has only the minimal information
+   necessary for linking.  We process this also, and use the information to
+   build gdb's minimal symbol table.  This gives us some minimal debugging
+   capability even for files compiled without -g.  */
+
+static void
+som_symfile_read (objfile, section_offsets, mainline)
+     struct objfile *objfile;
+     struct section_offsets *section_offsets;
+     int mainline;
+{
+  bfd *abfd = objfile->obfd;
+  struct cleanup *back_to;
+
+  do_pxdb (symfile_bfd_open (objfile->name));
+
+  init_minimal_symbol_collection ();
+  back_to = make_cleanup ((make_cleanup_func) discard_minimal_symbols, 0);
+
+  /* Read in the import list and the export list.  Currently
+     the export list isn't used; the import list is used in
+     hp-symtab-read.c to handle static vars declared in other
+     shared libraries. */
+  init_import_symbols (objfile);
+#if 0   /* Export symbols not used today 1997-08-05 */ 
+  init_export_symbols (objfile);
+#else
+  objfile->export_list = NULL;
+  objfile->export_list_size = 0;
+#endif
+
+  /* Process the normal SOM symbol table first. 
+     This reads in the DNTT and string table, but doesn't
+     actually scan the DNTT. It does scan the linker symbol
+     table and thus build up a "minimal symbol table". */
+ 
+  som_symtab_read (abfd, objfile, section_offsets);
+
+  /* Now read information from the stabs debug sections.
+     This is a no-op for SOM.
+     Perhaps it is intended for some kind of mixed STABS/SOM
+     situation? */    
+  stabsect_build_psymtabs (objfile, section_offsets, mainline,
+			   "$GDB_SYMBOLS$", "$GDB_STRINGS$", "$TEXT$");
+
+  /* Now read the native debug information. 
+     This builds the psymtab. This used to be done via a scan of
+     the DNTT, but is now done via the PXDB-built quick-lookup tables
+     together with a scan of the GNTT. See hp-psymtab-read.c. */
+  hpread_build_psymtabs (objfile, section_offsets, mainline);
+
+  /* Install any minimal symbols that have been collected as the current
+     minimal symbols for this objfile. 
+     Further symbol-reading is done incrementally, file-by-file,
+     in a step known as "psymtab-to-symtab" expansion. hp-symtab-read.c
+     contains the code to do the actual DNTT scanning and symtab building. */
+  install_minimal_symbols (objfile);
+
+  /* Force hppa-tdep.c to re-read the unwind descriptors.  */
+  objfile->obj_private = NULL;
+  do_cleanups (back_to);
+}
+
+/* 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).
+
+   We reinitialize buildsym, since we may be reading stabs from a SOM file.  */
+
+static void
+som_new_init (ignore)
+     struct objfile *ignore;
+{
+  stabsread_new_init ();
+  buildsym_new_init ();
+}
+
+/* Perform any local cleanups required when we are done with a particular
+   objfile.  I.E, we are in the process of discarding all symbol information
+   for an objfile, freeing up all memory held for it, and unlinking the
+   objfile struct from the global list of known objfiles. */
+
+static void
+som_symfile_finish (objfile)
+     struct objfile *objfile;
+{
+  if (objfile -> sym_stab_info != NULL)
+    {
+      mfree (objfile -> md, objfile -> sym_stab_info);
+    }
+  hpread_symfile_finish (objfile);
+}
+
+/* SOM specific initialization routine for reading symbols.  */
+
+static void
+som_symfile_init (objfile)
+     struct objfile *objfile;
+{
+  /* SOM objects may be reordered, so set OBJF_REORDERED.  If we
+     find this causes a significant slowdown in gdb then we could
+     set it in the debug symbol readers only when necessary.  */
+  objfile->flags |= OBJF_REORDERED;
+  hpread_symfile_init (objfile);
+}
+
+/* SOM specific parsing routine for section offsets.
+
+   Plain and simple for now.  */
+
+static struct section_offsets *
+som_symfile_offsets (objfile, addr)
+     struct objfile *objfile;
+     CORE_ADDR addr;
+{
+  struct section_offsets *section_offsets;
+  int i;
+
+  objfile->num_sections = SECT_OFF_MAX;
+  section_offsets = (struct section_offsets *)
+    obstack_alloc (&objfile -> psymbol_obstack, SIZEOF_SECTION_OFFSETS);
+
+  /* First see if we're a shared library.  If so, get the section
+     offsets from the library, else get them from addr.  */
+  if (!som_solib_section_offsets (objfile, section_offsets))
+    {
+      for (i = 0; i < SECT_OFF_MAX; i++)
+	ANOFFSET (section_offsets, i) = addr;
+    }
+
+  return section_offsets;
+}
+
+
+
+/* Check if a given symbol NAME is in the import list
+   of OBJFILE.
+   1 => true, 0 => false
+   This is used in hp_symtab_read.c to deal with static variables
+   that are defined in a different shared library than the one
+   whose symbols are being processed. */ 
+
+int is_in_import_list (name, objfile)
+  char * name;
+  struct objfile * objfile;
+{
+  register int i;
+
+  if (!objfile ||
+      !name ||
+      !*name)
+    return 0;
+
+  for (i=0; i < objfile->import_list_size; i++)
+    if (objfile->import_list[i] && STREQ (name, objfile->import_list[i]))
+        return 1;
+  return 0;
+}
+
+
+/* Read in and initialize the SOM import list which is present
+   for all executables and shared libraries.  The import list
+   consists of the symbols that are referenced in OBJFILE but
+   not defined there.  (Variables that are imported are dealt
+   with as "loc_indirect" vars.)
+   Return value = number of import symbols read in. */
+int
+init_import_symbols (objfile)
+  struct objfile * objfile;
+{
+  unsigned int import_list;
+  unsigned int import_list_size;
+  unsigned int string_table;
+  unsigned int string_table_size;
+  char * string_buffer;
+  register int i;
+  register int j;
+  register int k;
+  asection * text_section;      /* section handle */ 
+  unsigned int dl_header[12];   /* SOM executable header */ 
+
+  /* A struct for an entry in the SOM import list */
+  typedef struct {
+    int name;              /* index into the string table */ 
+    short dont_care1;      /* we don't use this */ 
+    unsigned char type;    /* 0 = NULL, 2 = Data, 3 = Code, 7 = Storage, 13 = Plabel */ 
+    unsigned int reserved2 : 8; /* not used */ 
+  } SomImportEntry;
+
+  /* We read 100 entries in at a time from the disk file. */ 
+# define SOM_READ_IMPORTS_NUM         100
+# define SOM_READ_IMPORTS_CHUNK_SIZE  (sizeof (SomImportEntry) * SOM_READ_IMPORTS_NUM)
+  SomImportEntry buffer[SOM_READ_IMPORTS_NUM];
+  
+  /* Initialize in case we error out */
+  objfile->import_list = NULL;
+  objfile->import_list_size = 0;
+
+#if 0  /* DEBUGGING */
+  printf ("Processing import list for %s\n", objfile->name);
+#endif
+
+  /* It doesn't work, for some reason, to read in space $TEXT$;
+     the subspace $SHLIB_INFO$ has to be used.  Some BFD quirk? pai/1997-08-05 */ 
+  text_section = bfd_get_section_by_name (objfile->obfd, "$SHLIB_INFO$");
+  if (!text_section)
+    return 0;
+  /* Get the SOM executable header */ 
+  bfd_get_section_contents (objfile->obfd, text_section, dl_header, 0, 12 * sizeof (int));
+
+  /* Check header version number for 10.x HP-UX */
+  /* Currently we deal only with 10.x systems; on 9.x the version # is 89060912.
+     FIXME: Change for future HP-UX releases and mods to the SOM executable format */ 
+  if (dl_header[0] != 93092112)
+    return 0;
+  
+  import_list = dl_header[4];     
+  import_list_size = dl_header[5];
+  if (!import_list_size)
+    return 0;
+  string_table = dl_header[10];     
+  string_table_size = dl_header[11];
+  if (!string_table_size)
+    return 0;
+
+  /* Suck in SOM string table */ 
+  string_buffer = (char *) xmalloc (string_table_size);
+  bfd_get_section_contents (objfile->obfd, text_section, string_buffer,
+                            string_table, string_table_size);
+
+  /* Allocate import list in the psymbol obstack; this has nothing
+     to do with psymbols, just a matter of convenience.  We want the
+     import list to be freed when the objfile is deallocated */ 
+  objfile->import_list
+    = (ImportEntry *) obstack_alloc (&objfile->psymbol_obstack,
+                                      import_list_size * sizeof (ImportEntry));
+
+  /* Read in the import entries, a bunch at a time */ 
+  for (j=0, k=0;
+       j < (import_list_size / SOM_READ_IMPORTS_NUM);
+       j++)
+    {
+      bfd_get_section_contents (objfile->obfd, text_section, buffer,
+                                import_list + j * SOM_READ_IMPORTS_CHUNK_SIZE,
+                                SOM_READ_IMPORTS_CHUNK_SIZE);
+      for (i=0; i < SOM_READ_IMPORTS_NUM; i++, k++)
+        {
+          if (buffer[i].type != (unsigned char) 0) 
+            {
+              objfile->import_list[k]
+                = (char *) obstack_alloc (&objfile->psymbol_obstack, strlen (string_buffer + buffer[i].name) + 1);
+              strcpy (objfile->import_list[k], string_buffer + buffer[i].name);
+              /* Some day we might want to record the type and other information too */ 
+            }
+          else /* null type */ 
+            objfile->import_list[k] = NULL;
+          
+#if 0 /* DEBUGGING */
+          printf ("Import String %d:%d (%d), type %d is %s\n", j, i, k,
+                  (int) buffer[i].type, objfile->import_list[k]);
+#endif
+        }
+    }
+
+  /* Get the leftovers */ 
+  if (k < import_list_size)
+    bfd_get_section_contents (objfile->obfd, text_section, buffer,
+                              import_list + k * sizeof (SomImportEntry),
+                              (import_list_size - k) * sizeof (SomImportEntry));
+  for (i=0; k < import_list_size; i++, k++)
+    {
+      if (buffer[i].type != (unsigned char) 0)
+        {
+          objfile->import_list[k]
+            = (char *) obstack_alloc (&objfile->psymbol_obstack, strlen (string_buffer + buffer[i].name) + 1);
+          strcpy (objfile->import_list[k], string_buffer + buffer[i].name);
+          /* Some day we might want to record the type and other information too */ 
+        }
+      else
+        objfile->import_list[k] = NULL;
+#if 0 /* DEBUGGING */ 
+      printf ("Import String F:%d (%d), type %d, is %s\n", i, k,
+              (int) buffer[i].type, objfile->import_list[k]);
+#endif
+    }
+
+  objfile->import_list_size = import_list_size;
+  free (string_buffer);
+  return import_list_size;
+}
+
+/* Read in and initialize the SOM export list which is present
+   for all executables and shared libraries.  The import list
+   consists of the symbols that are referenced in OBJFILE but
+   not defined there.  (Variables that are imported are dealt
+   with as "loc_indirect" vars.)
+   Return value = number of import symbols read in. */
+int
+init_export_symbols (objfile)
+  struct objfile * objfile;
+{
+  unsigned int export_list;
+  unsigned int export_list_size;
+  unsigned int string_table;
+  unsigned int string_table_size;
+  char * string_buffer;
+  register int i;
+  register int j;
+  register int k;
+  asection * text_section;    /* section handle */  
+  unsigned int dl_header[12]; /* SOM executable header */ 
+
+  /* A struct for an entry in the SOM export list */
+  typedef struct {
+    int next;    /* for hash table use -- we don't use this */ 
+    int name;    /* index into string table */ 
+    int value;   /* offset or plabel */
+    int dont_care1;     /* not used */ 
+    unsigned char type; /* 0 = NULL, 2 = Data, 3 = Code, 7 = Storage, 13 = Plabel */ 
+    char dont_care2;    /* not used */ 
+    short dont_care3;   /* not used */ 
+  } SomExportEntry;
+
+  /* We read 100 entries in at a time from the disk file. */ 
+# define SOM_READ_EXPORTS_NUM         100  
+# define SOM_READ_EXPORTS_CHUNK_SIZE  (sizeof (SomExportEntry) * SOM_READ_EXPORTS_NUM)
+  SomExportEntry buffer[SOM_READ_EXPORTS_NUM];
+
+  /* Initialize in case we error out */
+  objfile->export_list = NULL;
+  objfile->export_list_size = 0;
+
+#if 0  /* DEBUGGING */
+  printf ("Processing export list for %s\n", objfile->name);
+#endif
+
+  /* It doesn't work, for some reason, to read in space $TEXT$;
+     the subspace $SHLIB_INFO$ has to be used.  Some BFD quirk? pai/1997-08-05 */ 
+  text_section = bfd_get_section_by_name (objfile->obfd, "$SHLIB_INFO$");
+  if (!text_section)
+    return 0;
+  /* Get the SOM executable header */ 
+  bfd_get_section_contents (objfile->obfd, text_section, dl_header, 0, 12 * sizeof (int));
+
+  /* Check header version number for 10.x HP-UX */
+  /* Currently we deal only with 10.x systems; on 9.x the version # is 89060912.
+     FIXME: Change for future HP-UX releases and mods to the SOM executable format */ 
+  if (dl_header[0] != 93092112)
+    return 0;
+  
+  export_list = dl_header[8];      
+  export_list_size = dl_header[9]; 
+  if (!export_list_size)
+    return 0;
+  string_table = dl_header[10];     
+  string_table_size = dl_header[11];
+  if (!string_table_size)
+    return 0;
+
+  /* Suck in SOM string table */ 
+  string_buffer = (char *) xmalloc (string_table_size);
+  bfd_get_section_contents (objfile->obfd, text_section, string_buffer,
+                            string_table, string_table_size);
+
+  /* Allocate export list in the psymbol obstack; this has nothing
+     to do with psymbols, just a matter of convenience.  We want the
+     export list to be freed when the objfile is deallocated */ 
+  objfile->export_list
+    = (ExportEntry *)  obstack_alloc (&objfile->psymbol_obstack,
+                                      export_list_size * sizeof (ExportEntry));
+
+  /* Read in the export entries, a bunch at a time */ 
+  for (j=0, k=0;
+       j < (export_list_size / SOM_READ_EXPORTS_NUM);
+       j++)
+    {
+      bfd_get_section_contents (objfile->obfd, text_section, buffer,
+                                export_list + j * SOM_READ_EXPORTS_CHUNK_SIZE,
+                                SOM_READ_EXPORTS_CHUNK_SIZE);
+      for (i=0; i < SOM_READ_EXPORTS_NUM; i++, k++)
+        {
+          if (buffer[i].type != (unsigned char) 0)
+            {
+              objfile->export_list[k].name
+                = (char *) obstack_alloc (&objfile->psymbol_obstack, strlen (string_buffer + buffer[i].name) + 1);
+              strcpy (objfile->export_list[k].name, string_buffer + buffer[i].name);
+              objfile->export_list[k].address = buffer[i].value;
+              /* Some day we might want to record the type and other information too */ 
+            }
+          else /* null type */ 
+            { 
+              objfile->export_list[k].name = NULL;
+              objfile->export_list[k].address = 0;
+            }
+#if 0 /* DEBUGGING */
+          printf ("Export String %d:%d (%d), type %d is %s\n", j, i, k,
+                  (int) buffer[i].type, objfile->export_list[k].name);
+#endif
+        }
+    }
+
+  /* Get the leftovers */ 
+  if (k < export_list_size)
+    bfd_get_section_contents (objfile->obfd, text_section, buffer,
+                              export_list + k * sizeof (SomExportEntry),
+                              (export_list_size - k) * sizeof (SomExportEntry));
+  for (i=0; k < export_list_size; i++, k++)
+    {
+      if (buffer[i].type != (unsigned char) 0)
+        {
+          objfile->export_list[k].name
+            = (char *) obstack_alloc (&objfile->psymbol_obstack, strlen (string_buffer + buffer[i].name) + 1);
+          strcpy (objfile->export_list[k].name, string_buffer + buffer[i].name);
+          /* Some day we might want to record the type and other information too */ 
+          objfile->export_list[k].address = buffer[i].value;
+        }
+      else
+        {
+          objfile->export_list[k].name = NULL;
+          objfile->export_list[k].address = 0;
+        }
+#if 0 /* DEBUGGING */ 
+      printf ("Export String F:%d (%d), type %d, value %x is %s\n", i, k,
+              (int) buffer[i].type, buffer[i].value, objfile->export_list[k].name);
+#endif
+    }
+
+  objfile->export_list_size = export_list_size;
+  free (string_buffer);
+  return export_list_size;
+}
+
+
+
+/* Register that we are able to handle SOM object file formats.  */
+
+static struct sym_fns som_sym_fns =
+{
+  bfd_target_som_flavour,
+  som_new_init,		/* sym_new_init: init anything gbl to entire symtab */
+  som_symfile_init,	/* sym_init: read initial info, setup for sym_read() */
+  som_symfile_read,	/* sym_read: read a symbol file into symtab */
+  som_symfile_finish,	/* sym_finish: finished with file, cleanup */
+  som_symfile_offsets,	/* sym_offsets:  Translate ext. to int. relocation */
+  NULL			/* next: pointer to next struct sym_fns */
+};
+
+void
+_initialize_somread ()
+{
+  add_symtab_fns (&som_sym_fns);
+}