0861c11703ade3d20992e56e78fc5a598e7f0091
1 /* Work with executable files, for GDB.
2 Copyright (C) 1988, 1989 Free Software Foundation, Inc.
4 This file is part of GDB.
6 GDB is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 1, or (at your option)
11 GDB is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GDB; see the file COPYING. If not, write to
18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
28 #include <sys/types.h>
31 #include <sys/param.h>
36 #ifdef STILL_NEEDED_FOR_DECSTATION
37 #include <sys/dir.h> /* For DECstations */
38 #include <sys/user.h> /* After a.out.h */
44 extern char *getenv();
45 extern void child_create_inferior (), child_attach ();
46 extern void add_syms_addr_command ();
47 extern void symbol_file_command ();
49 /* The Binary File Descriptor handle for the executable file. */
53 /* The base and bounds of the table of the exec file's sections. */
55 struct section_table
*exec_sections
, *exec_sections_end
;
59 extern struct target_ops exec_ops
;
72 exec_file_command (filename
, from_tty
)
76 target_preopen (from_tty
);
78 /* Remove any previous exec file. */
79 unpush_target (&exec_ops
);
81 /* Now open and digest the file the user requested, if any. */
85 char *scratch_pathname
;
88 filename
= tilde_expand (filename
);
89 make_cleanup (free
, filename
);
91 /* FIXME, if writeable is set, open for read/write. */
92 scratch_chan
= openp (getenv ("PATH"), 1, filename
, O_RDONLY
, 0,
95 perror_with_name (filename
);
97 exec_bfd
= bfd_fdopenr (scratch_pathname
, NULL
, scratch_chan
);
99 error ("Could not open `%s' as an executable file: %s",
100 scratch_pathname
, bfd_errmsg (bfd_error
));
101 if (!bfd_check_format (exec_bfd
, bfd_object
))
102 error ("\"%s\": not in executable format: %s.",
103 scratch_pathname
, bfd_errmsg (bfd_error
));
106 /* This code needs to be incorporated into BFD */
107 #ifdef COFF_ENCAPSULATE
108 /* If we have a coff header, it can give us better values for
109 text_start and exec_data_start. This is particularly useful
110 for remote debugging of embedded systems. */
111 if (N_FLAGS(exec_aouthdr
) & N_FLAGS_COFF_ENCAPSULATE
)
113 struct coffheader ch
;
115 val
= lseek (execchan
, -(sizeof (AOUTHDR
) + sizeof (ch
)), 1);
117 perror_with_name (filename
);
118 val
= myread (execchan
, &ch
, sizeof (ch
));
120 perror_with_name (filename
);
121 text_start
= ch
.text_start
;
122 exec_data_start
= ch
.data_start
;
127 IS_OBJECT_FILE (exec_aouthdr
) ? 0 : N_TXTADDR (exec_aouthdr
);
128 exec_data_start
= IS_OBJECT_FILE (exec_aouthdr
)
129 ? exec_aouthdr
.a_text
: N_DATADDR (exec_aouthdr
);
133 if (build_section_table (exec_bfd
, &exec_sections
, &exec_sections_end
))
134 error ("Can't find the file sections in `%s': %s",
135 exec_bfd
->filename
, bfd_errmsg (bfd_error
));
139 push_target (&exec_ops
);
141 /* Tell display code (if any) about the changed file name. */
142 if (exec_file_display_hook
)
143 (*exec_file_display_hook
) (filename
);
146 printf ("No exec file now.\n");
149 /* Set both the exec file and the symbol file, in one command.
150 What a novelty. Why did GDB go through four major releases before this
151 command was added? */
154 file_command (arg
, from_tty
)
158 /* FIXME, if we lose on reading the symbol file, we should revert
159 the exec file, but that's rough. */
160 exec_file_command (arg
, from_tty
);
161 symbol_file_command (arg
, from_tty
);
165 /* Locate all mappable sections of a BFD file. */
168 add_to_section_table (abfd
, asect
, table_pp
)
171 struct section_table
**table_pp
;
175 aflag
= bfd_get_section_flags (abfd
, asect
);
176 /* FIXME, we need to handle BSS segment here...it alloc's but doesn't load */
177 if (!(aflag
& SEC_LOAD
))
179 (*table_pp
)->sec_ptr
= asect
;
180 (*table_pp
)->addr
= bfd_section_vma (abfd
, asect
);
181 (*table_pp
)->endaddr
= (*table_pp
)->addr
+ bfd_section_size (abfd
, asect
);
186 build_section_table (some_bfd
, start
, end
)
188 struct section_table
**start
, **end
;
192 count
= bfd_count_sections (some_bfd
);
194 abort(); /* return 1? */
195 *start
= (struct section_table
*) xmalloc (count
* sizeof (**start
));
197 bfd_map_over_sections (some_bfd
, add_to_section_table
, end
);
198 if (*end
> *start
+ count
)
200 /* We could realloc the table, but it probably loses for most files. */
204 /* Read or write the exec file.
206 Args are address within exec file, address within gdb address-space,
207 length, and a flag indicating whether to read or write.
211 0: We cannot handle this address and length.
212 > 0: We have handled N bytes starting at this address.
213 (If N == length, we did it all.) We might be able
214 to handle more bytes beyond this length, but no
216 < 0: We cannot handle this address, but if somebody
217 else handles (-N) bytes, we can start from there.
219 The same routine is used to handle both core and exec files;
220 we just tail-call it with more arguments to select between them. */
223 xfer_memory (memaddr
, myaddr
, len
, write
, abfd
, sections
, sections_end
)
229 struct section_table
*sections
, *sections_end
;
232 struct section_table
*p
;
233 CORE_ADDR nextsectaddr
, memend
;
234 boolean (*xfer_fn
) ();
239 memend
= memaddr
+ len
;
240 xfer_fn
= write
? bfd_set_section_contents
: bfd_get_section_contents
;
241 nextsectaddr
= memend
;
243 for (p
= sections
; p
< sections_end
; p
++)
245 if (p
->addr
<= memaddr
)
246 if (p
->endaddr
>= memend
)
248 /* Entire transfer is within this section. */
249 res
= xfer_fn (abfd
, p
->sec_ptr
, myaddr
, memaddr
- p
->addr
, len
);
250 return (res
!= false)? len
: 0;
252 else if (p
->endaddr
<= memaddr
)
254 /* This section ends before the transfer starts. */
259 /* This section overlaps the transfer. Just do half. */
260 len
= p
->endaddr
- memaddr
;
261 res
= xfer_fn (abfd
, p
->sec_ptr
, myaddr
, memaddr
- p
->addr
, len
);
262 return (res
!= false)? len
: 0;
264 else if (p
->addr
< nextsectaddr
)
265 nextsectaddr
= p
->addr
;
268 if (nextsectaddr
>= memend
)
269 return 0; /* We can't help */
271 return - (nextsectaddr
- memaddr
); /* Next boundary where we can help */
274 /* The function called by target_xfer_memory via our target_ops */
277 exec_xfer_memory (memaddr
, myaddr
, len
, write
)
283 return xfer_memory (memaddr
, myaddr
, len
, write
,
284 exec_bfd
, exec_sections
, exec_sections_end
);
289 #ifdef REG_STACK_SEGMENT
291 /* Pyramids and AM29000s have an extra segment in the virtual address space
292 for the (control) stack of register-window frames. The AM29000 folk
293 call it the "register stack" rather than the "memory stack". */
294 else if (memaddr
>= reg_stack_start
&& memaddr
< reg_stack_end
)
296 i
= min (len
, reg_stack_end
- memaddr
);
297 fileptr
= memaddr
- reg_stack_start
+ reg_stack_offset
;
298 wanna_xfer
= coredata
;
300 #endif /* REG_STACK_SEGMENT */
306 struct section_table
*p
;
308 printf ("\tExecutable file `%s'.\n", bfd_get_filename(exec_bfd
));
310 for (p
= exec_sections
; p
< exec_sections_end
; p
++)
311 printf("\texecutable from 0x%08x to 0x%08x is %s\n",
313 bfd_section_name (exec_bfd
, p
->sec_ptr
));
317 set_section_command (args
, from_tty
)
321 struct section_table
*p
;
324 unsigned long secaddr
;
329 error ("Must specify section name and its virtual address");
331 /* Parse out section name */
332 for (secname
= args
; !isspace(*args
); args
++) ;
333 seclen
= args
- secname
;
335 /* Parse out new virtual address */
336 secaddr
= parse_and_eval_address (args
);
338 for (p
= exec_sections
; p
< exec_sections_end
; p
++) {
339 if (!strncmp (secname
, bfd_section_name (exec_bfd
, p
->sec_ptr
), seclen
)
340 && bfd_section_name (exec_bfd
, p
->sec_ptr
)[seclen
] == '\0') {
341 offset
= secaddr
- p
->addr
;
343 p
->endaddr
+= offset
;
348 if (seclen
>= sizeof (secprint
))
349 seclen
= sizeof (secprint
) - 1;
350 strncpy (secprint
, secname
, seclen
);
351 secprint
[seclen
] = '\0';
352 error ("Section %s not found", secprint
);
355 struct target_ops exec_ops
= {
356 "exec", "Local exec file",
357 "Use an executable file as a target.\n\
358 Specify the filename of the executable file.",
359 exec_file_command
, exec_close
, /* open, close */
360 child_attach
, 0, 0, 0, /* attach, detach, resume, wait, */
361 0, 0, /* fetch_registers, store_registers, */
362 0, 0, 0, /* prepare_to_store, conv_to, conv_from, */
363 exec_xfer_memory
, exec_files_info
,
364 0, 0, /* insert_breakpoint, remove_breakpoint, */
365 0, 0, 0, 0, 0, /* terminal stuff */
366 0, 0, /* kill, load */
367 add_syms_addr_command
,
368 0, 0, /* call fn, lookup sym */
369 child_create_inferior
,
370 0, /* mourn_inferior */
371 file_stratum
, 0, /* next */
372 0, 1, 0, 0, 0, /* all mem, mem, stack, regs, exec */
373 OPS_MAGIC
, /* Always the last thing */
380 add_com ("file", class_files
, file_command
,
381 "Use FILE as program to be debugged.\n\
382 It is read for its symbols, for getting the contents of pure memory,\n\
383 and it is the program executed when you use the `run' command.\n\
384 If FILE cannot be found as specified, your execution directory path\n\
385 ($PATH) is searched for a command of that name.\n\
386 No arg means to have no executable file and no symbols.");
388 add_com ("exec-file", class_files
, exec_file_command
,
389 "Use FILE as program for getting contents of pure memory.\n\
390 If FILE cannot be found as specified, your execution directory path\n\
391 is searched for a command of that name.\n\
392 No arg means have no executable file.");
394 add_com ("section", class_files
, set_section_command
,
395 "Change the base address of section SECTION of the exec file to ADDR.\n\
396 This can be used if the exec file does not contain section addresses,\n\
397 (such as in the a.out format), or when the addresses specified in the\n\
398 file itself are wrong. Each section must be changed separately. The\n\
399 ``info files'' command lists all the sections and their addresses.");
401 add_target (&exec_ops
);