Initial revision

1 files changed, 511 insertions, 0 deletions

diff --git a/gdb/corelow.c b/gdb/corelow.c
new file mode 100644
index 00000000000..e635257b2f4
--- /dev/null
+++ b/gdb/corelow.c
@@ -0,0 +1,511 @@
+/* Core dump and executable file functions below target vector, for GDB.
+   Copyright 1986, 87, 89, 91, 92, 93, 94, 95, 96, 97, 1998
+   Free Software Foundation, Inc.
+
+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 "gdb_string.h"
+#include <errno.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include "frame.h"  /* required by inferior.h */
+#include "inferior.h"
+#include "symtab.h"
+#include "command.h"
+#include "bfd.h"
+#include "target.h"
+#include "gdbcore.h"
+#include "gdbthread.h"
+
+/* List of all available core_fns.  On gdb startup, each core file register
+   reader calls add_core_fns() to register information on each core format it
+   is prepared to read. */
+
+static struct core_fns *core_file_fns = NULL;
+
+static void core_files_info PARAMS ((struct target_ops *));
+
+#ifdef SOLIB_ADD
+static int solib_add_stub PARAMS ((PTR));
+#endif
+
+static void core_open PARAMS ((char *, int));
+
+static void core_detach PARAMS ((char *, int));
+
+static void core_close PARAMS ((int));
+
+static void get_core_registers PARAMS ((int));
+
+static void add_to_thread_list PARAMS ((bfd *, asection *, PTR));
+
+static int ignore PARAMS ((CORE_ADDR, char *));
+
+static char *core_file_to_sym_file PARAMS ((char *));
+
+static int core_file_thread_alive PARAMS ((int tid));
+
+static void init_core_ops PARAMS ((void));
+
+void _initialize_corelow PARAMS ((void));
+
+struct target_ops core_ops;
+
+/* Link a new core_fns into the global core_file_fns list.  Called on gdb
+   startup by the _initialize routine in each core file register reader, to
+   register information about each format the the reader is prepared to
+   handle. */
+
+void
+add_core_fns (cf)
+     struct core_fns *cf;
+{
+  cf -> next = core_file_fns;
+  core_file_fns = cf;
+}
+
+
+/* Discard all vestiges of any previous core file and mark data and stack
+   spaces as empty.  */
+
+/* ARGSUSED */
+static void
+core_close (quitting)
+     int quitting;
+{
+  char *name;
+
+  if (core_bfd)
+    {
+      inferior_pid = 0;		/* Avoid confusion from thread stuff */
+
+      name = bfd_get_filename (core_bfd);
+      if (!bfd_close (core_bfd))
+	warning ("cannot close \"%s\": %s",
+		 name, bfd_errmsg (bfd_get_error ()));
+      free (name);
+      core_bfd = NULL;
+#ifdef CLEAR_SOLIB
+      CLEAR_SOLIB ();
+#endif
+      if (core_ops.to_sections)
+	{
+	  free ((PTR)core_ops.to_sections);
+	  core_ops.to_sections = NULL;
+	  core_ops.to_sections_end = NULL;
+	}
+    }
+}
+
+#ifdef SOLIB_ADD
+/* Stub function for catch_errors around shared library hacking.  FROM_TTYP
+   is really an int * which points to from_tty.  */
+
+static int 
+solib_add_stub (from_ttyp)
+     PTR from_ttyp;
+{
+  SOLIB_ADD (NULL, *(int *)from_ttyp, &current_target);
+  re_enable_breakpoints_in_shlibs ();
+  return 0;
+}
+#endif /* SOLIB_ADD */
+
+/* Look for sections whose names start with `.reg/' so that we can extract the
+   list of threads in a core file.  */
+
+static void
+add_to_thread_list (abfd, asect, reg_sect_arg)
+     bfd *abfd;
+     asection *asect;
+     PTR reg_sect_arg;
+{
+  int thread_id;
+  asection *reg_sect = (asection *) reg_sect_arg;
+
+  if (strncmp (bfd_section_name (abfd, asect), ".reg/", 5) != 0)
+    return;
+
+  thread_id = atoi (bfd_section_name (abfd, asect) + 5);
+
+  add_thread (thread_id);
+
+/* Warning, Will Robinson, looking at BFD private data! */
+
+  if (reg_sect != NULL
+      && asect->filepos == reg_sect->filepos) /* Did we find .reg? */
+    inferior_pid = thread_id;	/* Yes, make it current */
+}
+
+/* This routine opens and sets up the core file bfd.  */
+
+static void
+core_open (filename, from_tty)
+     char *filename;
+     int from_tty;
+{
+  const char *p;
+  int siggy;
+  struct cleanup *old_chain;
+  char *temp;
+  bfd *temp_bfd;
+  int ontop;
+  int scratch_chan;
+
+  target_preopen (from_tty);
+  if (!filename)
+    {
+      error (core_bfd ? 
+       "No core file specified.  (Use `detach' to stop debugging a core file.)"
+     : "No core file specified.");
+    }
+
+  filename = tilde_expand (filename);
+  if (filename[0] != '/')
+    {
+      temp = concat (current_directory, "/", filename, NULL);
+      free (filename);
+      filename = temp;
+    }
+
+  old_chain = make_cleanup (free, filename);
+
+  scratch_chan = open (filename, write_files ? O_RDWR : O_RDONLY, 0);
+  if (scratch_chan < 0)
+    perror_with_name (filename);
+
+  temp_bfd = bfd_fdopenr (filename, gnutarget, scratch_chan);
+  if (temp_bfd == NULL)
+    perror_with_name (filename);
+
+  if (!bfd_check_format (temp_bfd, bfd_core))
+    {
+      /* Do it after the err msg */
+      /* FIXME: should be checking for errors from bfd_close (for one thing,
+	 on error it does not free all the storage associated with the
+	 bfd).  */
+      make_cleanup ((make_cleanup_func) bfd_close, temp_bfd);
+      error ("\"%s\" is not a core dump: %s",
+	     filename, bfd_errmsg (bfd_get_error ()));
+    }
+
+  /* Looks semi-reasonable.  Toss the old core file and work on the new.  */
+
+  discard_cleanups (old_chain);		/* Don't free filename any more */
+  unpush_target (&core_ops);
+  core_bfd = temp_bfd;
+  old_chain = make_cleanup ((make_cleanup_func) core_close, core_bfd);
+
+  validate_files ();
+
+  /* Find the data section */
+  if (build_section_table (core_bfd, &core_ops.to_sections,
+			   &core_ops.to_sections_end))
+    error ("\"%s\": Can't find sections: %s",
+	   bfd_get_filename (core_bfd), bfd_errmsg (bfd_get_error ()));
+
+  ontop = !push_target (&core_ops);
+  discard_cleanups (old_chain);
+
+  p = bfd_core_file_failing_command (core_bfd);
+  if (p)
+    printf_filtered ("Core was generated by `%s'.\n", p);
+
+  siggy = bfd_core_file_failing_signal (core_bfd);
+  if (siggy > 0)
+    printf_filtered ("Program terminated with signal %d, %s.\n", siggy,
+		     safe_strsignal (siggy));
+
+  /* Build up thread list from BFD sections. */
+
+  init_thread_list ();
+  bfd_map_over_sections (core_bfd, add_to_thread_list,
+			 bfd_get_section_by_name (core_bfd, ".reg"));
+
+  if (ontop)
+    {
+      /* Fetch all registers from core file.  */
+      target_fetch_registers (-1);
+
+      /* Add symbols and section mappings for any shared libraries.  */
+#ifdef SOLIB_ADD
+      catch_errors (solib_add_stub, &from_tty, (char *)0,
+		    RETURN_MASK_ALL);
+#endif
+
+      /* Now, set up the frame cache, and print the top of stack.  */
+      flush_cached_frames ();
+      select_frame (get_current_frame (), 0);
+      print_stack_frame (selected_frame, selected_frame_level, 1);
+    }
+  else
+    {
+      warning (
+"you won't be able to access this core file until you terminate\n\
+your %s; do ``info files''", target_longname);
+    }
+}
+
+static void
+core_detach (args, from_tty)
+     char *args;
+     int from_tty;
+{
+  if (args)
+    error ("Too many arguments");
+  unpush_target (&core_ops);
+  reinit_frame_cache ();
+  if (from_tty)
+    printf_filtered ("No core file now.\n");
+}
+
+/* Get the registers out of a core file.  This is the machine-
+   independent part.  Fetch_core_registers is the machine-dependent
+   part, typically implemented in the xm-file for each architecture.  */
+
+/* We just get all the registers, so we don't use regno.  */
+
+/* ARGSUSED */
+static void
+get_core_registers (regno)
+     int regno;
+{
+  sec_ptr reg_sec;
+  unsigned size;
+  char *the_regs;
+  char secname[30];
+  enum bfd_flavour our_flavour = bfd_get_flavour (core_bfd);
+  struct core_fns *cf = NULL;
+
+  if (core_file_fns == NULL)
+    {
+      fprintf_filtered (gdb_stderr,
+			"Can't fetch registers from this type of core file\n");
+      return;
+    }
+
+  /* Thread support.  If inferior_pid is non-zero, then we have found a core
+     file with threads (or multiple processes).  In that case, we need to
+     use the appropriate register section, else we just use `.reg'. */
+
+  /* XXX - same thing needs to be done for floating-point (.reg2) sections. */
+
+  if (inferior_pid)
+    sprintf (secname, ".reg/%d", inferior_pid);
+  else
+    strcpy (secname, ".reg");
+
+  reg_sec = bfd_get_section_by_name (core_bfd, secname);
+  if (!reg_sec)
+    goto cant;
+  size = bfd_section_size (core_bfd, reg_sec);
+  the_regs = alloca (size);
+  /* Look for the core functions that match this flavor.  Default to the
+     first one if nothing matches. */
+  for (cf = core_file_fns; cf != NULL; cf = cf -> next)
+    {
+      if (our_flavour == cf -> core_flavour)
+	{
+	  break;
+	}
+    }
+  if (cf == NULL)
+    {
+      cf = core_file_fns;
+    }
+  if (cf != NULL &&
+      bfd_get_section_contents (core_bfd, reg_sec, the_regs, (file_ptr)0, size) &&
+      cf -> core_read_registers != NULL)
+    {
+      (cf -> core_read_registers (the_regs, size, 0,
+				  (unsigned) bfd_section_vma (abfd,reg_sec)));
+    }
+  else
+    {
+cant:
+      fprintf_filtered (gdb_stderr,
+			"Couldn't fetch registers from core file: %s\n",
+			bfd_errmsg (bfd_get_error ()));
+    }
+
+  /* Now do it again for the float registers, if they exist.  */
+  reg_sec = bfd_get_section_by_name (core_bfd, ".reg2");
+  if (reg_sec)
+    {
+      size = bfd_section_size (core_bfd, reg_sec);
+      the_regs = alloca (size);
+      if (cf != NULL &&
+	  bfd_get_section_contents (core_bfd, reg_sec, the_regs, (file_ptr)0, size) &&
+	  cf -> core_read_registers != NULL)
+	{
+	  (cf -> core_read_registers (the_regs, size, 2,
+				      (unsigned) bfd_section_vma (abfd,reg_sec)));
+	}
+      else
+	{
+	  fprintf_filtered (gdb_stderr, 
+			    "Couldn't fetch register set 2 from core file: %s\n",
+			    bfd_errmsg (bfd_get_error ()));
+	}
+    }
+  registers_fetched ();
+}
+
+static char *
+core_file_to_sym_file (core)
+  char *  core;
+{
+  CONST char *  failing_command;
+  char *  p;
+  char *  temp;
+  bfd *  temp_bfd;
+  int  scratch_chan;
+
+  if (! core)
+    error ("No core file specified.");
+
+  core = tilde_expand (core);
+  if (core[0] != '/')
+    {
+      temp = concat (current_directory, "/", core, NULL);
+      core = temp;
+    }
+
+  scratch_chan = open (core, write_files ? O_RDWR : O_RDONLY, 0);
+  if (scratch_chan < 0)
+    perror_with_name (core);
+
+  temp_bfd = bfd_fdopenr (core, gnutarget, scratch_chan);
+  if (temp_bfd == NULL)
+    perror_with_name (core);
+
+  if (!bfd_check_format (temp_bfd, bfd_core))
+    {
+      /* Do it after the err msg */
+      /* FIXME: should be checking for errors from bfd_close (for one thing,
+	 on error it does not free all the storage associated with the
+	 bfd).  */
+      make_cleanup ((make_cleanup_func) bfd_close, temp_bfd);
+      error ("\"%s\" is not a core dump: %s",
+	     core, bfd_errmsg (bfd_get_error ()));
+    }
+
+  /* Find the data section */
+  if (build_section_table (temp_bfd, &core_ops.to_sections,
+			   &core_ops.to_sections_end))
+    error ("\"%s\": Can't find sections: %s",
+	   bfd_get_filename (temp_bfd), bfd_errmsg (bfd_get_error ()));
+
+  failing_command = bfd_core_file_failing_command (temp_bfd);
+
+  bfd_close (temp_bfd);
+
+  /* If we found a filename, remember that it is probably saved
+     relative to the executable that created it.  If working directory
+     isn't there now, we may not be able to find the executable.  Rather
+     than trying to be sauve about finding it, just check if the file
+     exists where we are now.  If not, then punt and tell our client
+     we couldn't find the sym file.
+     */
+  p = (char *) failing_command;
+  if ((p != NULL) && (access (p, F_OK) != 0))
+    p = NULL;
+
+  return p;
+}
+
+static void
+core_files_info (t)
+  struct target_ops *t;
+{
+  print_section_info (t, core_bfd);
+}
+
+/* If mourn is being called in all the right places, this could be say
+   `gdb internal error' (since generic_mourn calls breakpoint_init_inferior).  */
+
+static int
+ignore (addr, contents)
+     CORE_ADDR addr;
+     char *contents;
+{
+  return 0;
+}
+
+
+/* Okay, let's be honest: threads gleaned from a core file aren't
+   exactly lively, are they?  On the other hand, if we don't claim
+   that each & every one is alive, then we don't get any of them
+   to appear in an "info thread" command, which is quite a useful
+   behaviour.
+   */
+static int
+core_file_thread_alive (tid)
+  int  tid;
+{
+  return 1;
+}
+
+/* Fill in core_ops with its defined operations and properties.  */
+
+static void
+init_core_ops ()
+{
+  core_ops.to_shortname = "core";
+  core_ops.to_longname = "Local core dump file";
+  core_ops.to_doc =
+    "Use a core file as a target.  Specify the filename of the core file.";
+  core_ops.to_open = core_open;
+  core_ops.to_close = core_close;
+  core_ops.to_attach = find_default_attach;
+  core_ops.to_require_attach = find_default_require_attach;
+  core_ops.to_detach = core_detach;
+  core_ops.to_require_detach = find_default_require_detach;
+  core_ops.to_fetch_registers = get_core_registers;
+  core_ops.to_xfer_memory = xfer_memory;
+  core_ops.to_files_info = core_files_info;
+  core_ops.to_insert_breakpoint = ignore;
+  core_ops.to_remove_breakpoint = ignore;
+  core_ops.to_create_inferior = find_default_create_inferior;
+  core_ops.to_clone_and_follow_inferior = find_default_clone_and_follow_inferior;
+  core_ops.to_thread_alive = core_file_thread_alive;
+  core_ops.to_core_file_to_sym_file = core_file_to_sym_file;
+  core_ops.to_stratum = core_stratum;
+  core_ops.to_has_memory = 1;
+  core_ops.to_has_stack = 1;
+  core_ops.to_has_registers = 1;
+  core_ops.to_magic = OPS_MAGIC;	
+}
+
+/* non-zero if we should not do the add_target call in
+   _initialize_corelow; not initialized (i.e., bss) so that
+   the target can initialize it (i.e., data) if appropriate.
+   This needs to be set at compile time because we don't know
+   for sure whether the target's initialize routine is called
+   before us or after us. */
+int coreops_suppress_target;
+
+void
+_initialize_corelow ()
+{
+  init_core_ops ();
+
+  if (!coreops_suppress_target)
+    add_target (&core_ops);
+}