5f8f398d83f7ea533ebdcfae19508790eb1ed312
1 /* Work with executable files, for GDB.
2 Copyright (C) 1988, 1989 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program 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 2 of the License, or
9 (at your option) any later version.
11 This program 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 this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
29 #include <sys/types.h>
32 #include <sys/param.h>
41 extern char *getenv();
42 extern void child_create_inferior (), child_attach ();
43 extern void symbol_file_command ();
45 /* The Binary File Descriptor handle for the executable file. */
49 /* Whether to open exec and core files read-only or read-write. */
53 /* Text start and end addresses (KLUDGE) if needed */
55 #if NEED_TEXT_START_END
56 CORE_ADDR text_start
= 0;
57 CORE_ADDR text_end
= 0;
62 extern struct target_ops exec_ops
;
73 if (exec_ops
.sections
) {
74 free (exec_ops
.sections
);
75 exec_ops
.sections
= NULL
;
76 exec_ops
.sections_end
= NULL
;
81 exec_file_command (filename
, from_tty
)
85 target_preopen (from_tty
);
87 /* Remove any previous exec file. */
88 unpush_target (&exec_ops
);
90 /* Now open and digest the file the user requested, if any. */
94 char *scratch_pathname
;
97 filename
= tilde_expand (filename
);
98 make_cleanup (free
, filename
);
100 scratch_chan
= openp (getenv ("PATH"), 1, filename
,
101 write_files
? O_RDWR
: O_RDONLY
, 0,
103 if (scratch_chan
< 0)
104 perror_with_name (filename
);
106 exec_bfd
= bfd_fdopenr (scratch_pathname
, NULL
, scratch_chan
);
108 error ("Could not open `%s' as an executable file: %s",
109 scratch_pathname
, bfd_errmsg (bfd_error
));
110 if (!bfd_check_format (exec_bfd
, bfd_object
))
111 error ("\"%s\": not in executable format: %s.",
112 scratch_pathname
, bfd_errmsg (bfd_error
));
115 /* This code needs to be incorporated into BFD */
116 #ifdef COFF_ENCAPSULATE
117 /* If we have a coff header, it can give us better values for
118 text_start and exec_data_start. This is particularly useful
119 for remote debugging of embedded systems. */
120 if (N_FLAGS(exec_aouthdr
) & N_FLAGS_COFF_ENCAPSULATE
)
122 struct coffheader ch
;
124 val
= lseek (execchan
, -(sizeof (AOUTHDR
) + sizeof (ch
)), 1);
126 perror_with_name (filename
);
127 val
= myread (execchan
, &ch
, sizeof (ch
));
129 perror_with_name (filename
);
130 text_start
= ch
.text_start
;
131 exec_data_start
= ch
.data_start
;
136 IS_OBJECT_FILE (exec_aouthdr
) ? 0 : N_TXTADDR (exec_aouthdr
);
137 exec_data_start
= IS_OBJECT_FILE (exec_aouthdr
)
138 ? exec_aouthdr
.a_text
: N_DATADDR (exec_aouthdr
);
142 if (build_section_table (exec_bfd
, &exec_ops
.sections
,
143 &exec_ops
.sections_end
))
144 error ("Can't find the file sections in `%s': %s",
145 exec_bfd
->filename
, bfd_errmsg (bfd_error
));
147 #if NEED_TEXT_START_END
148 /* This is a KLUDGE (FIXME) because a few places in a few ports
149 (29K springs to mind) need this info for now. */
151 struct section_table
*p
;
152 for (p
= exec_ops
.sections
; p
< exec_ops
.sections_end
; p
++)
153 if (!strcmp (".text", bfd_section_name (p
->bfd
, p
->sec_ptr
))
154 text_start
= p
->addr
;
155 text_end
= p
->endaddr
;
161 push_target (&exec_ops
);
163 /* Tell display code (if any) about the changed file name. */
164 if (exec_file_display_hook
)
165 (*exec_file_display_hook
) (filename
);
168 printf ("No exec file now.\n");
171 /* Set both the exec file and the symbol file, in one command.
172 What a novelty. Why did GDB go through four major releases before this
173 command was added? */
176 file_command (arg
, from_tty
)
180 /* FIXME, if we lose on reading the symbol file, we should revert
181 the exec file, but that's rough. */
182 exec_file_command (arg
, from_tty
);
183 symbol_file_command (arg
, from_tty
);
187 /* Locate all mappable sections of a BFD file.
188 table_pp_char is a char * to get it through bfd_map_over_sections;
189 we cast it back to its proper type. */
192 add_to_section_table (abfd
, asect
, table_pp_char
)
197 struct section_table
**table_pp
= (struct section_table
**)table_pp_char
;
200 aflag
= bfd_get_section_flags (abfd
, asect
);
201 /* FIXME, we need to handle BSS segment here...it alloc's but doesn't load */
202 if (!(aflag
& SEC_LOAD
))
204 (*table_pp
)->bfd
= abfd
;
205 (*table_pp
)->sec_ptr
= asect
;
206 (*table_pp
)->addr
= bfd_section_vma (abfd
, asect
);
207 (*table_pp
)->endaddr
= (*table_pp
)->addr
+ bfd_section_size (abfd
, asect
);
212 build_section_table (some_bfd
, start
, end
)
214 struct section_table
**start
, **end
;
218 count
= bfd_count_sections (some_bfd
);
220 abort(); /* return 1? */
223 *start
= (struct section_table
*) xmalloc (count
* sizeof (**start
));
225 bfd_map_over_sections (some_bfd
, add_to_section_table
, (char *)end
);
226 if (*end
> *start
+ count
)
228 /* We could realloc the table, but it probably loses for most files. */
232 /* Read or write the exec file.
234 Args are address within a BFD file, address within gdb address-space,
235 length, and a flag indicating whether to read or write.
239 0: We cannot handle this address and length.
240 > 0: We have handled N bytes starting at this address.
241 (If N == length, we did it all.) We might be able
242 to handle more bytes beyond this length, but no
244 < 0: We cannot handle this address, but if somebody
245 else handles (-N) bytes, we can start from there.
247 The same routine is used to handle both core and exec files;
248 we just tail-call it with more arguments to select between them. */
251 xfer_memory (memaddr
, myaddr
, len
, write
, target
)
256 struct target_ops
*target
;
259 struct section_table
*p
;
260 CORE_ADDR nextsectaddr
, memend
;
261 boolean (*xfer_fn
) ();
266 memend
= memaddr
+ len
;
267 xfer_fn
= write
? bfd_set_section_contents
: bfd_get_section_contents
;
268 nextsectaddr
= memend
;
270 for (p
= target
->sections
; p
< target
->sections_end
; p
++)
272 if (p
->addr
<= memaddr
)
273 if (p
->endaddr
>= memend
)
275 /* Entire transfer is within this section. */
276 res
= xfer_fn (p
->bfd
, p
->sec_ptr
, myaddr
, memaddr
- p
->addr
, len
);
277 return (res
!= false)? len
: 0;
279 else if (p
->endaddr
<= memaddr
)
281 /* This section ends before the transfer starts. */
286 /* This section overlaps the transfer. Just do half. */
287 len
= p
->endaddr
- memaddr
;
288 res
= xfer_fn (p
->bfd
, p
->sec_ptr
, myaddr
, memaddr
- p
->addr
, len
);
289 return (res
!= false)? len
: 0;
291 else if (p
->addr
< nextsectaddr
)
292 nextsectaddr
= p
->addr
;
295 if (nextsectaddr
>= memend
)
296 return 0; /* We can't help */
298 return - (nextsectaddr
- memaddr
); /* Next boundary where we can help */
302 #ifdef REG_STACK_SEGMENT
304 /* Pyramids and AM29000s have an extra segment in the virtual address space
305 for the (control) stack of register-window frames. The AM29000 folk
306 call it the "register stack" rather than the "memory stack". */
307 else if (memaddr
>= reg_stack_start
&& memaddr
< reg_stack_end
)
309 i
= min (len
, reg_stack_end
- memaddr
);
310 fileptr
= memaddr
- reg_stack_start
+ reg_stack_offset
;
311 wanna_xfer
= coredata
;
313 #endif /* REG_STACK_SEGMENT */
319 struct section_table
*p
;
321 printf ("\tExecutable file `%s'.\n", bfd_get_filename(exec_bfd
));
323 for (p
= exec_ops
.sections
; p
< exec_ops
.sections_end
; p
++)
324 printf("\texecutable from 0x%08x to 0x%08x is %s\n",
326 bfd_section_name (exec_bfd
, p
->sec_ptr
));
330 set_section_command (args
, from_tty
)
334 struct section_table
*p
;
337 unsigned long secaddr
;
342 error ("Must specify section name and its virtual address");
344 /* Parse out section name */
345 for (secname
= args
; !isspace(*args
); args
++) ;
346 seclen
= args
- secname
;
348 /* Parse out new virtual address */
349 secaddr
= parse_and_eval_address (args
);
351 for (p
= exec_ops
.sections
; p
< exec_ops
.sections_end
; p
++) {
352 if (!strncmp (secname
, bfd_section_name (exec_bfd
, p
->sec_ptr
), seclen
)
353 && bfd_section_name (exec_bfd
, p
->sec_ptr
)[seclen
] == '\0') {
354 offset
= secaddr
- p
->addr
;
356 p
->endaddr
+= offset
;
361 if (seclen
>= sizeof (secprint
))
362 seclen
= sizeof (secprint
) - 1;
363 strncpy (secprint
, secname
, seclen
);
364 secprint
[seclen
] = '\0';
365 error ("Section %s not found", secprint
);
368 struct target_ops exec_ops
= {
369 "exec", "Local exec file",
370 "Use an executable file as a target.\n\
371 Specify the filename of the executable file.",
372 exec_file_command
, exec_close
, /* open, close */
373 child_attach
, 0, 0, 0, /* attach, detach, resume, wait, */
374 0, 0, /* fetch_registers, store_registers, */
375 0, 0, 0, /* prepare_to_store, conv_to, conv_from, */
376 xfer_memory
, exec_files_info
,
377 0, 0, /* insert_breakpoint, remove_breakpoint, */
378 0, 0, 0, 0, 0, /* terminal stuff */
379 0, 0, /* kill, load */
380 0, 0, /* call fn, lookup sym */
381 child_create_inferior
,
382 0, /* mourn_inferior */
383 file_stratum
, 0, /* next */
384 0, 1, 0, 0, 0, /* all mem, mem, stack, regs, exec */
385 0, 0, /* section pointers */
386 OPS_MAGIC
, /* Always the last thing */
393 add_com ("file", class_files
, file_command
,
394 "Use FILE as program to be debugged.\n\
395 It is read for its symbols, for getting the contents of pure memory,\n\
396 and it is the program executed when you use the `run' command.\n\
397 If FILE cannot be found as specified, your execution directory path\n\
398 ($PATH) is searched for a command of that name.\n\
399 No arg means to have no executable file and no symbols.");
401 add_com ("exec-file", class_files
, exec_file_command
,
402 "Use FILE as program for getting contents of pure memory.\n\
403 If FILE cannot be found as specified, your execution directory path\n\
404 is searched for a command of that name.\n\
405 No arg means have no executable file.");
407 add_com ("section", class_files
, set_section_command
,
408 "Change the base address of section SECTION of the exec file to ADDR.\n\
409 This can be used if the exec file does not contain section addresses,\n\
410 (such as in the a.out format), or when the addresses specified in the\n\
411 file itself are wrong. Each section must be changed separately. The\n\
412 ``info files'' command lists all the sections and their addresses.");
415 (add_set_cmd ("write", class_support
, var_boolean
, (char *)&write_files
,
416 "Set writing into executable and core files.",
420 add_target (&exec_ops
);