gdb/state.h

   1 /* Support for dumping and reloading various pieces of GDB's internal state.
   2    Copyright 1992 Free Software Foundation, Inc.
   3    Contributed by Cygnus Support, using pieces from other GDB modules.
   4
   5 This file is part of GDB.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 /* This file provides definitions used for reading and writing gdb
  22    state files.  State files have a fairly simple form which is intended
  23    to be easily extensible.  See state.c for further documentation. */
  24
  25 #if !defined (_STATE_H)
  26 #define _STATE_H
  27
  28 /* State file-header */
  29
  30 typedef struct {
  31   unsigned char sf_mag0;        /* Magic number byte 0 */
  32   unsigned char sf_mag1;        /* Magic number byte 1 */
  33   unsigned char sf_mag2;        /* Magic number byte 2 */
  34   unsigned char sf_mag3;        /* Magic number byte 3 */
  35   unsigned long sf_ftoff;       /* File offset to start of form-tree */
  36   unsigned long sf_ftsize;      /* Size of the form-tree, in bytes */
  37 } sf_hdr;
  38
  39
  40 #define SF_MAG0 'g'             /* Magic number byte 0 value */
  41 #define SF_MAG1 'd'             /* Magic number byte 1 value */
  42 #define SF_MAG2 'b'             /* Magic number byte 2 value */
  43 #define SF_MAG3 '\000'          /* Magic number byte 3 value */
  44
  45 #define SF_GOOD_MAGIC(asfd) ((asfd) -> hdr.sf_mag0 == SF_MAG0 && \
  46                              (asfd) -> hdr.sf_mag1 == SF_MAG1 && \
  47                              (asfd) -> hdr.sf_mag2 == SF_MAG2 && \
  48                              (asfd) -> hdr.sf_mag3 == SF_MAG3)
  49
  50 /* The internal form-tree is formed from nodes that contain pointers
  51    to the first sibling, the first child, a backpointer to the parent,
  52    and a pointer to the actual data for the node.  This allows all
  53    tree nodes to have the same sized structure, but support variable
  54    numbers of child nodes per parent node.  The backpointer for the
  55    parent is required for simplier tree walks. */
  56
  57 struct formnode
  58 {
  59   struct formnode *sibling;     /* Pointer to first sibling */
  60   struct formnode *child;       /* Pointer to first child */
  61   struct formnode *parent;      /* Backpointer to parent */
  62   char *nodedata;               /* Pointer to the nodes data */
  63   unsigned long treesize;       /* Size of subtree rooted here */
  64 };
  65
  66 /* A state file descriptor is defined by the following structure. */
  67
  68 typedef struct
  69 {
  70   char *filename;               /* Full pathname of the state file */
  71   FILE *fp;                     /* Open file pointer for the state file */
  72   sf_hdr hdr;                   /* Copy of the state file-header */
  73   char *formtree;               /* Pointer to in-memory copy of form-tree */
  74 } sfd;
  75
  76 extern sfd *
  77 sfd_fopen PARAMS ((char *, char *));
  78
  79 extern void
  80 sfd_fclose PARAMS ((sfd *));
  81
  82 extern struct objfile *
  83 objfile_from_statefile PARAMS ((sfd *));
  84
  85 #endif  /* !defined (_STATE_H) */