]>
code.delx.au - gnu-emacs/blob - src/unexec.c
1 /* Copyright (C) 1985,86,87,88,92,93,94 Free Software Foundation, Inc.
3 This file is part of GNU Emacs.
5 GNU Emacs is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2, or (at your option)
10 GNU Emacs is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNU Emacs; see the file COPYING. If not, write to
17 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
21 * unexec.c - Convert a running program into an a.out file.
23 * Author: Spencer W. Thomas
24 * Computer Science Dept.
26 * Date: Tue Mar 2 1982
27 * Modified heavily since then.
30 * unexec (new_name, a_name, data_start, bss_start, entry_address)
31 * char *new_name, *a_name;
32 * unsigned data_start, bss_start, entry_address;
34 * Takes a snapshot of the program and makes an a.out format file in the
35 * file named by the string argument new_name.
36 * If a_name is non-NULL, the symbol table will be taken from the given file.
37 * On some machines, an existing a_name file is required.
39 * The boundaries within the a.out file may be adjusted with the data_start
40 * and bss_start arguments. Either or both may be given as 0 for defaults.
42 * Data_start gives the boundary between the text segment and the data
43 * segment of the program. The text segment can contain shared, read-only
44 * program code and literal data, while the data segment is always unshared
45 * and unprotected. Data_start gives the lowest unprotected address.
46 * The value you specify may be rounded down to a suitable boundary
47 * as required by the machine you are using.
49 * Specifying zero for data_start means the boundary between text and data
50 * should not be the same as when the program was loaded.
51 * If NO_REMAP is defined, the argument data_start is ignored and the
52 * segment boundaries are never changed.
54 * Bss_start indicates how much of the data segment is to be saved in the
55 * a.out file and restored when the program is executed. It gives the lowest
56 * unsaved address, and is rounded up to a page boundary. The default when 0
57 * is given assumes that the entire data segment is to be stored, including
58 * the previous data and bss as well as any additional storage allocated with
61 * The new file is set up to start at entry_address.
63 * If you make improvements I'd like to get them too.
64 * harpo!utah-cs!thomas, thomas@Utah-20
68 /* Modified to support SysVr3 shared libraries by James Van Artsdalen
69 * of Dell Computer Corporation. james@bigtex.cactus.org.
72 /* There are several compilation parameters affecting unexec:
76 Define this if your system uses COFF for executables.
80 Define this if you are using the GNU coff encapsulated a.out format.
81 This is closer to a.out than COFF. You should *not* define COFF if
82 you define COFF_ENCAPSULATE
84 Otherwise we assume you use Berkeley format.
88 Define this if you do not want to try to save Emacs's pure data areas
89 as part of the text segment.
91 Saving them as text is good because it allows users to share more.
93 However, on machines that locate the text area far from the data area,
94 the boundary cannot feasibly be moved. Such machines require
97 Also, remapping can cause trouble with the built-in startup routine
98 /lib/crt0.o, which defines `environ' as an initialized variable.
99 Dumping `environ' as pure does not work! So, to use remapping,
100 you must write a startup routine for your machine in Emacs's crt0.c.
101 If NO_REMAP is defined, Emacs uses the system's crt0.o.
105 Some machines that use COFF executables require that each section
106 start on a certain boundary *in the COFF file*. Such machines should
107 define SECTION_ALIGNMENT to a mask of the low-order bits that must be
108 zero on such a boundary. This mask is used to control padding between
109 segments in the COFF file.
111 If SECTION_ALIGNMENT is not defined, the segments are written
112 consecutively with no attempt at alignment. This is right for
117 Some machines require that the beginnings and ends of segments
118 *in core* be on certain boundaries. For most machines, a page
119 boundary is sufficient. That is the default. When a larger
120 boundary is needed, define SEGMENT_MASK to a mask of
121 the bits that must be zero on such a boundary.
125 Some machines count the a.out header as part of the size of the text
126 segment (a_text); they may actually load the header into core as the
127 first data in the text segment. Some have additional padding between
128 the header and the real text of the program that is counted in a_text.
130 For these machines, define A_TEXT_OFFSET(HDR) to examine the header
131 structure HDR and return the number of bytes to add to `a_text'
132 before writing it (above and beyond the number of bytes of actual
133 program text). HDR's standard fields are already correct, except that
134 this adjustment to the `a_text' field has not yet been made;
135 thus, the amount of offset can depend on the data in the file.
139 If defined, this macro specifies the number of bytes to seek into the
140 a.out file before starting to write the text segment.a
144 For machines using COFF, this macro, if defined, is a value stored
145 into the magic number field of the output file.
149 This macro can be used to generate statements to adjust or
150 initialize nonstandard fields in the file header
154 Macro to correct an int which is the bit pattern of a pointer to a byte
155 into an int which is the number of a byte.
157 This macro has a default definition which is usually right.
158 This default definition is a no-op on most machines (where a
159 pointer looks like an int) but not on all machines.
164 #define PERROR(arg) perror (arg); return -1
168 #define PERROR(file) report_error (file, new)
171 #ifndef CANNOT_DUMP /* all rest of file! */
173 #ifndef CANNOT_UNEXEC /* most of rest of file */
175 #ifdef COFF_ENCAPSULATE
176 int need_coff_header
= 1;
177 #include <coff-encap/a.out.encap.h> /* The location might be a poor assumption */
181 #define filehdr external_filehdr
182 #define scnhdr external_scnhdr
183 #define syment external_syment
184 #define auxent external_auxent
185 #define n_numaux e_numaux
186 #define n_type e_type
189 unsigned short magic
; /* type of file */
190 unsigned short vstamp
; /* version stamp */
191 unsigned long tsize
; /* text size in bytes, padded to FW bdry*/
192 unsigned long dsize
; /* initialized data " " */
193 unsigned long bsize
; /* uninitialized data " " */
194 unsigned long entry
; /* entry pt. */
195 unsigned long text_start
;/* base of text used for this file */
196 unsigned long data_start
;/* base of data used for this file */
200 #else /* not MSDOS */
202 #endif /* not MSDOS */
205 /* Define getpagesize () if the system does not.
206 Note that this may depend on symbols defined in a.out.h
208 #include "getpagesize.h"
210 #ifndef makedev /* Try to detect types.h already loaded */
211 #include <sys/types.h>
214 #include <sys/stat.h>
217 extern char *start_of_text (); /* Start of text */
218 extern char *start_of_data (); /* Start of initialized data */
221 static long block_copy_start
; /* Old executable start point */
222 static struct filehdr f_hdr
; /* File header */
223 static struct aouthdr f_ohdr
; /* Optional file header (a.out) */
224 long bias
; /* Bias to add for growth */
225 long lnnoptr
; /* Pointer to line-number info within file */
226 #define SYMS_START block_copy_start
228 static long text_scnptr
;
229 static long data_scnptr
;
234 extern void *sbrk ();
237 /* Some systems with __STDC__ compilers still declare this `char *' in some
238 header file, and our declaration conflicts. The return value is always
239 cast, so it should be harmless to leave it undefined. Hopefully
240 machines with different size pointers and ints declare sbrk in a header
243 extern void *sbrk ();
245 extern char *sbrk ();
246 #endif /* __STDC__ */
250 #define SYMS_START ((long) N_SYMOFF (ohdr))
252 /* Some machines override the structure name for an a.out header. */
253 #ifndef EXEC_HDR_TYPE
254 #define EXEC_HDR_TYPE struct exec
259 #define MY_ID HP9000S200_ID
263 #endif /* no HP9000S200_ID */
264 static MAGIC OLDMAGIC
= {MY_ID
, SHARE_MAGIC
};
265 static MAGIC NEWMAGIC
= {MY_ID
, DEMAND_MAGIC
};
266 #define N_TXTOFF(x) TEXT_OFFSET(x)
267 #define N_SYMOFF(x) LESYM_OFFSET(x)
268 static EXEC_HDR_TYPE hdr
, ohdr
;
272 #if defined (USG) && !defined (IBMAIX) && !defined (IRIS) && !defined (COFF_ENCAPSULATE) && !defined (LINUX)
273 static struct bhdr hdr
, ohdr
;
274 #define a_magic fmagic
279 #define a_trsize rtsize
280 #define a_drsize rdsize
281 #define a_entry entry
282 #define N_BADMAG(x) \
283 (((x).fmagic)!=OMAGIC && ((x).fmagic)!=NMAGIC &&\
284 ((x).fmagic)!=FMAGIC && ((x).fmagic)!=IMAGIC)
285 #define NEWMAGIC FMAGIC
286 #else /* IRIS or IBMAIX or not USG */
287 static EXEC_HDR_TYPE hdr
, ohdr
;
288 #define NEWMAGIC ZMAGIC
289 #endif /* IRIS or IBMAIX not USG */
290 #endif /* not HPUX */
292 static int unexec_text_start
;
293 static int unexec_data_start
;
295 #ifdef COFF_ENCAPSULATE
296 /* coffheader is defined in the GNU a.out.encap.h file. */
297 struct coffheader coffheader
;
300 #endif /* not COFF */
304 /* Correct an int which is the bit pattern of a pointer to a byte
305 into an int which is the number of a byte.
306 This is a no-op on ordinary machines, but not on all. */
308 #ifndef ADDR_CORRECT /* Let m-*.h files override this definition */
309 #define ADDR_CORRECT(x) ((char *)(x) - (char*)0)
315 report_error (file
, fd
)
321 error ("Failure operating on %s\n", file
);
325 #define ERROR0(msg) report_error_1 (new, msg, 0, 0); return -1
326 #define ERROR1(msg,x) report_error_1 (new, msg, x, 0); return -1
327 #define ERROR2(msg,x,y) report_error_1 (new, msg, x, y); return -1
330 report_error_1 (fd
, msg
, a1
, a2
)
339 fprintf (stderr
, msg
, a1
, a2
);
340 fprintf (stderr
, "\n");
344 static int make_hdr ();
345 static int copy_text_and_data ();
346 static int copy_sym ();
347 static void mark_x ();
349 /* ****************************************************************
354 unexec (new_name
, a_name
, data_start
, bss_start
, entry_address
)
355 char *new_name
, *a_name
;
356 unsigned data_start
, bss_start
, entry_address
;
360 if (a_name
&& (a_out
= open (a_name
, 0)) < 0)
364 if ((new = creat (new_name
, 0666)) < 0)
369 if (make_hdr (new, a_out
, data_start
, bss_start
, entry_address
, a_name
, new_name
) < 0
370 || copy_text_and_data (new, a_out
) < 0
371 || copy_sym (new, a_out
, a_name
, new_name
) < 0
373 #ifndef COFF_BSD_SYMBOLS
374 || adjust_lnnoptrs (new, a_out
, new_name
) < 0
380 /* unlink (new_name); /* Failed, unlink new a.out */
391 /* ****************************************************************
394 * Make the header in the new a.out from the header in core.
395 * Modify the text and data sizes.
398 make_hdr (new, a_out
, data_start
, bss_start
, entry_address
, a_name
, new_name
)
400 unsigned data_start
, bss_start
, entry_address
;
406 auto struct scnhdr f_thdr
; /* Text section header */
407 auto struct scnhdr f_dhdr
; /* Data section header */
408 auto struct scnhdr f_bhdr
; /* Bss section header */
409 auto struct scnhdr scntemp
; /* Temporary section header */
412 #ifdef USG_SHARED_LIBRARIES
413 extern unsigned int bss_end
;
415 unsigned int bss_end
;
418 pagemask
= getpagesize () - 1;
420 /* Adjust text/data boundary. */
422 data_start
= (int) start_of_data ();
423 #else /* not NO_REMAP */
425 data_start
= (int) start_of_data ();
426 #endif /* not NO_REMAP */
427 data_start
= ADDR_CORRECT (data_start
);
430 data_start
= data_start
& ~SEGMENT_MASK
; /* (Down) to segment boundary. */
432 data_start
= data_start
& ~pagemask
; /* (Down) to page boundary. */
435 bss_end
= ADDR_CORRECT (sbrk (0)) + pagemask
;
436 bss_end
&= ~ pagemask
;
438 /* Adjust data/bss boundary. */
441 bss_start
= (ADDR_CORRECT (bss_start
) + pagemask
);
442 /* (Up) to page bdry. */
443 bss_start
&= ~ pagemask
;
444 if (bss_start
> bss_end
)
446 ERROR1 ("unexec: Specified bss_start (%u) is past end of program",
453 if (data_start
> bss_start
) /* Can't have negative data size. */
455 ERROR2 ("unexec: data_start (%u) can't be greater than bss_start (%u)",
456 data_start
, bss_start
);
460 /* Salvage as much info from the existing file as possible */
463 if (read (a_out
, &f_hdr
, sizeof (f_hdr
)) != sizeof (f_hdr
))
467 block_copy_start
+= sizeof (f_hdr
);
468 if (f_hdr
.f_opthdr
> 0)
470 if (read (a_out
, &f_ohdr
, sizeof (f_ohdr
)) != sizeof (f_ohdr
))
474 block_copy_start
+= sizeof (f_ohdr
);
476 /* Loop through section headers, copying them in */
477 for (scns
= f_hdr
.f_nscns
; scns
> 0; scns
--) {
478 if (read (a_out
, &scntemp
, sizeof (scntemp
)) != sizeof (scntemp
))
482 if (scntemp
.s_scnptr
> 0L)
484 if (block_copy_start
< scntemp
.s_scnptr
+ scntemp
.s_size
)
485 block_copy_start
= scntemp
.s_scnptr
+ scntemp
.s_size
;
487 if (strcmp (scntemp
.s_name
, ".text") == 0)
491 else if (strcmp (scntemp
.s_name
, ".data") == 0)
495 else if (strcmp (scntemp
.s_name
, ".bss") == 0)
503 ERROR0 ("can't build a COFF file from scratch yet");
506 /* Now we alter the contents of all the f_*hdr variables
507 to correspond to what we want to dump. */
509 #ifdef USG_SHARED_LIBRARIES
511 /* The amount of data we're adding to the file is distance from the
512 * end of the original .data space to the current end of the .data
516 bias
= bss_start
- (f_ohdr
.data_start
+ f_dhdr
.s_size
);
520 f_hdr
.f_flags
|= (F_RELFLG
| F_EXEC
);
525 f_ohdr
.magic
= EXEC_MAGIC
;
528 f_ohdr
.text_start
= (long) start_of_text ();
529 f_ohdr
.tsize
= data_start
- f_ohdr
.text_start
;
530 f_ohdr
.data_start
= data_start
;
531 #endif /* NO_REMAP */
532 f_ohdr
.dsize
= bss_start
- f_ohdr
.data_start
;
533 f_ohdr
.bsize
= bss_end
- bss_start
;
534 #ifndef KEEP_OLD_TEXT_SCNPTR
535 /* On some machines, the old values are right.
536 ??? Maybe on all machines with NO_REMAP. */
537 f_thdr
.s_size
= f_ohdr
.tsize
;
538 f_thdr
.s_scnptr
= sizeof (f_hdr
) + sizeof (f_ohdr
);
539 f_thdr
.s_scnptr
+= (f_hdr
.f_nscns
) * (sizeof (f_thdr
));
540 #endif /* KEEP_OLD_TEXT_SCNPTR */
541 #ifdef ADJUST_TEXT_SCNHDR_SIZE
542 /* On some machines, `text size' includes all headers. */
543 f_thdr
.s_size
-= f_thdr
.s_scnptr
;
544 #endif /* ADJUST_TEST_SCNHDR_SIZE */
545 lnnoptr
= f_thdr
.s_lnnoptr
;
546 #ifdef SECTION_ALIGNMENT
547 /* Some systems require special alignment
548 of the sections in the file itself. */
550 = (f_thdr
.s_scnptr
+ SECTION_ALIGNMENT
) & ~SECTION_ALIGNMENT
;
551 #endif /* SECTION_ALIGNMENT */
553 f_thdr
.s_scnptr
= 0xd0;
555 text_scnptr
= f_thdr
.s_scnptr
;
556 #ifdef ADJUST_TEXTBASE
557 text_scnptr
= sizeof (f_hdr
) + sizeof (f_ohdr
) + (f_hdr
.f_nscns
) * (sizeof (f_thdr
));
559 #ifndef KEEP_OLD_PADDR
560 f_dhdr
.s_paddr
= f_ohdr
.data_start
;
561 #endif /* KEEP_OLD_PADDR */
562 f_dhdr
.s_vaddr
= f_ohdr
.data_start
;
563 f_dhdr
.s_size
= f_ohdr
.dsize
;
564 f_dhdr
.s_scnptr
= f_thdr
.s_scnptr
+ f_thdr
.s_size
;
565 #ifdef SECTION_ALIGNMENT
566 /* Some systems require special alignment
567 of the sections in the file itself. */
569 = (f_dhdr
.s_scnptr
+ SECTION_ALIGNMENT
) & ~SECTION_ALIGNMENT
;
570 #endif /* SECTION_ALIGNMENT */
571 #ifdef DATA_SECTION_ALIGNMENT
572 /* Some systems require special alignment
573 of the data section only. */
575 = (f_dhdr
.s_scnptr
+ DATA_SECTION_ALIGNMENT
) & ~DATA_SECTION_ALIGNMENT
;
576 #endif /* DATA_SECTION_ALIGNMENT */
577 data_scnptr
= f_dhdr
.s_scnptr
;
578 #ifndef KEEP_OLD_PADDR
579 f_bhdr
.s_paddr
= f_ohdr
.data_start
+ f_ohdr
.dsize
;
580 #endif /* KEEP_OLD_PADDR */
581 f_bhdr
.s_vaddr
= f_ohdr
.data_start
+ f_ohdr
.dsize
;
582 f_bhdr
.s_size
= f_ohdr
.bsize
;
583 f_bhdr
.s_scnptr
= 0L;
584 #ifndef USG_SHARED_LIBRARIES
585 bias
= f_dhdr
.s_scnptr
+ f_dhdr
.s_size
- block_copy_start
;
588 if (f_hdr
.f_symptr
> 0L)
590 f_hdr
.f_symptr
+= bias
;
593 if (f_thdr
.s_lnnoptr
> 0L)
595 f_thdr
.s_lnnoptr
+= bias
;
598 #ifdef ADJUST_EXEC_HEADER
600 #endif /* ADJUST_EXEC_HEADER */
602 if (write (new, &f_hdr
, sizeof (f_hdr
)) != sizeof (f_hdr
))
607 if (write (new, &f_ohdr
, sizeof (f_ohdr
)) != sizeof (f_ohdr
))
612 #ifndef USG_SHARED_LIBRARIES
614 if (write (new, &f_thdr
, sizeof (f_thdr
)) != sizeof (f_thdr
))
619 if (write (new, &f_dhdr
, sizeof (f_dhdr
)) != sizeof (f_dhdr
))
624 if (write (new, &f_bhdr
, sizeof (f_bhdr
)) != sizeof (f_bhdr
))
629 #else /* USG_SHARED_LIBRARIES */
631 /* The purpose of this code is to write out the new file's section
634 * Scan through the original file's sections. If the encountered
635 * section is one we know (.text, .data or .bss), write out the
636 * correct header. If it is a section we do not know (such as
637 * .lib), adjust the address of where the section data is in the
638 * file, and write out the header.
640 * If any section precedes .text or .data in the file, this code
641 * will not adjust the file pointer for that section correctly.
644 lseek (a_out
, sizeof (f_hdr
) + sizeof (f_ohdr
), 0);
646 for (scns
= f_hdr
.f_nscns
; scns
> 0; scns
--)
648 if (read (a_out
, &scntemp
, sizeof (scntemp
)) != sizeof (scntemp
))
651 if (!strcmp (scntemp
.s_name
, f_thdr
.s_name
)) /* .text */
653 if (write (new, &f_thdr
, sizeof (f_thdr
)) != sizeof (f_thdr
))
656 else if (!strcmp (scntemp
.s_name
, f_dhdr
.s_name
)) /* .data */
658 if (write (new, &f_dhdr
, sizeof (f_dhdr
)) != sizeof (f_dhdr
))
661 else if (!strcmp (scntemp
.s_name
, f_bhdr
.s_name
)) /* .bss */
663 if (write (new, &f_bhdr
, sizeof (f_bhdr
)) != sizeof (f_bhdr
))
668 if (scntemp
.s_scnptr
)
669 scntemp
.s_scnptr
+= bias
;
670 if (write (new, &scntemp
, sizeof (scntemp
)) != sizeof (scntemp
))
674 #endif /* USG_SHARED_LIBRARIES */
678 #else /* if not COFF */
680 /* Get symbol table info from header of a.out file if given one. */
683 #ifdef COFF_ENCAPSULATE
684 if (read (a_out
, &coffheader
, sizeof coffheader
) != sizeof coffheader
)
688 if (coffheader
.f_magic
!= COFF_MAGIC
)
690 ERROR1("%s doesn't have legal coff magic number\n", a_name
);
693 if (read (a_out
, &ohdr
, sizeof hdr
) != sizeof hdr
)
700 ERROR1 ("invalid magic number in %s", a_name
);
706 #ifdef COFF_ENCAPSULATE
707 /* We probably could without too much trouble. The code is in gld
708 * but I don't have that much time or incentive.
710 ERROR0 ("can't build a COFF file from scratch yet");
712 #ifdef MSDOS /* Demacs 1.1.1 91/10/16 HIRANO Satoshi */
713 bzero ((void *)&hdr
, sizeof hdr
);
715 bzero (&hdr
, sizeof hdr
);
720 unexec_text_start
= (long) start_of_text ();
721 unexec_data_start
= data_start
;
723 /* Machine-dependent fixup for header, or maybe for unexec_text_start */
724 #ifdef ADJUST_EXEC_HEADER
726 #endif /* ADJUST_EXEC_HEADER */
730 if (entry_address
!= 0)
731 hdr
.a_entry
= entry_address
;
733 hdr
.a_bss
= bss_end
- bss_start
;
734 hdr
.a_data
= bss_start
- data_start
;
736 hdr
.a_text
= ohdr
.a_text
;
737 #else /* not NO_REMAP */
738 hdr
.a_text
= data_start
- unexec_text_start
;
741 hdr
.a_text
+= A_TEXT_OFFSET (ohdr
);
744 #endif /* not NO_REMAP */
746 #ifdef COFF_ENCAPSULATE
747 /* We are encapsulating BSD format within COFF format. */
749 struct coffscn
*tp
, *dp
, *bp
;
750 tp
= &coffheader
.scns
[0];
751 dp
= &coffheader
.scns
[1];
752 bp
= &coffheader
.scns
[2];
753 tp
->s_size
= hdr
.a_text
+ sizeof(struct exec
);
754 dp
->s_paddr
= data_start
;
755 dp
->s_vaddr
= data_start
;
756 dp
->s_size
= hdr
.a_data
;
757 bp
->s_paddr
= dp
->s_vaddr
+ dp
->s_size
;
758 bp
->s_vaddr
= bp
->s_paddr
;
759 bp
->s_size
= hdr
.a_bss
;
760 coffheader
.tsize
= tp
->s_size
;
761 coffheader
.dsize
= dp
->s_size
;
762 coffheader
.bsize
= bp
->s_size
;
763 coffheader
.text_start
= tp
->s_vaddr
;
764 coffheader
.data_start
= dp
->s_vaddr
;
766 if (write (new, &coffheader
, sizeof coffheader
) != sizeof coffheader
)
770 #endif /* COFF_ENCAPSULATE */
772 if (write (new, &hdr
, sizeof hdr
) != sizeof hdr
)
778 hdr
.a_text
-= A_TEXT_OFFSET (ohdr
);
783 #endif /* not COFF */
786 /* ****************************************************************
789 * Copy the text and data segments from memory to the new a.out
792 copy_text_and_data (new, a_out
)
800 #ifdef USG_SHARED_LIBRARIES
803 struct scnhdr scntemp
; /* Temporary section header */
805 /* The purpose of this code is to write out the new file's section
808 * Step through the section table. If we know the section (.text,
809 * .data) do the appropriate thing. Otherwise, if the section has
810 * no allocated space in the file (.bss), do nothing. Otherwise,
811 * the section has space allocated in the file, and is not a section
812 * we know. So just copy it.
815 lseek (a_out
, sizeof (struct filehdr
) + sizeof (struct aouthdr
), 0);
817 for (scns
= f_hdr
.f_nscns
; scns
> 0; scns
--)
819 if (read (a_out
, &scntemp
, sizeof (scntemp
)) != sizeof (scntemp
))
822 if (!strcmp (scntemp
.s_name
, ".text"))
824 lseek (new, (long) text_scnptr
, 0);
825 ptr
= (char *) f_ohdr
.text_start
;
826 end
= ptr
+ f_ohdr
.tsize
;
827 write_segment (new, ptr
, end
);
829 else if (!strcmp (scntemp
.s_name
, ".data"))
831 lseek (new, (long) data_scnptr
, 0);
832 ptr
= (char *) f_ohdr
.data_start
;
833 end
= ptr
+ f_ohdr
.dsize
;
834 write_segment (new, ptr
, end
);
836 else if (!scntemp
.s_scnptr
)
837 ; /* do nothing - no data for this section */
842 long old_a_out_ptr
= lseek (a_out
, 0, 1);
844 lseek (a_out
, scntemp
.s_scnptr
, 0);
845 for (size
= scntemp
.s_size
; size
> 0; size
-= sizeof (page
))
847 n
= size
> sizeof (page
) ? sizeof (page
) : size
;
848 if (read (a_out
, page
, n
) != n
|| write (new, page
, n
) != n
)
851 lseek (a_out
, old_a_out_ptr
, 0);
855 #else /* COFF, but not USG_SHARED_LIBRARIES */
857 lseek (new, (long) text_scnptr
, 0);
858 ptr
= (char *) f_ohdr
.text_start
;
859 #ifdef HEADER_INCL_IN_TEXT
860 /* For Gould UTX/32, text starts after headers */
861 ptr
= (char *) (ptr
+ text_scnptr
);
862 #endif /* HEADER_INCL_IN_TEXT */
863 end
= ptr
+ f_ohdr
.tsize
;
864 write_segment (new, ptr
, end
);
866 lseek (new, (long) data_scnptr
, 0);
867 ptr
= (char *) f_ohdr
.data_start
;
868 end
= ptr
+ f_ohdr
.dsize
;
869 write_segment (new, ptr
, end
);
871 #endif /* USG_SHARED_LIBRARIES */
873 #else /* if not COFF */
875 /* Some machines count the header as part of the text segment.
876 That is to say, the header appears in core
877 just before the address that start_of_text () returns.
878 For them, N_TXTOFF is the place where the header goes.
879 We must adjust the seek to the place after the header.
880 Note that at this point hdr.a_text does *not* count
881 the extra A_TEXT_OFFSET bytes, only the actual bytes of code. */
884 lseek (new, (long) A_TEXT_SEEK (hdr
), 0);
886 lseek (new, (long) N_TXTOFF (hdr
), 0);
887 #endif /* no A_TEXT_SEEK */
889 ptr
= (char *) unexec_text_start
;
890 end
= ptr
+ hdr
.a_text
;
891 write_segment (new, ptr
, end
);
893 ptr
= (char *) unexec_data_start
;
894 end
= ptr
+ hdr
.a_data
;
895 /* This lseek is certainly incorrect when A_TEXT_OFFSET
896 and I believe it is a no-op otherwise.
897 Let's see if its absence ever fails. */
898 /* lseek (new, (long) N_TXTOFF (hdr) + hdr.a_text, 0); */
899 write_segment (new, ptr
, end
);
901 #endif /* not COFF */
906 write_segment (new, ptr
, end
)
908 register char *ptr
, *end
;
910 register int i
, nwrite
, ret
;
915 bzero (zeros
, sizeof zeros
);
917 for (i
= 0; ptr
< end
;)
919 /* distance to next multiple of 128. */
920 nwrite
= (((int) ptr
+ 128) & -128) - (int) ptr
;
921 /* But not beyond specified end. */
922 if (nwrite
> end
- ptr
) nwrite
= end
- ptr
;
923 ret
= write (new, ptr
, nwrite
);
924 /* If write gets a page fault, it means we reached
925 a gap between the old text segment and the old data segment.
926 This gap has probably been remapped into part of the text segment.
927 So write zeros for it. */
933 write (new, zeros
, nwrite
);
934 else if (nwrite
!= ret
)
937 "unexec write failure: addr 0x%x, fileno %d, size 0x%x, wrote 0x%x, errno %d",
938 ptr
, new, nwrite
, ret
, errno
);
946 /* ****************************************************************
949 * Copy the relocation information and symbol table from the a.out to the new
952 copy_sym (new, a_out
, a_name
, new_name
)
954 char *a_name
, *new_name
;
963 if (SYMS_START
== 0L)
968 if (lnnoptr
) /* if there is line number info */
969 lseek (a_out
, lnnoptr
, 0); /* start copying from there */
972 lseek (a_out
, SYMS_START
, 0); /* Position a.out to symtab. */
974 while ((n
= read (a_out
, page
, sizeof page
)) > 0)
976 if (write (new, page
, n
) != n
)
988 /* ****************************************************************
991 * After successfully building the new a.out, mark it executable
999 int new = 0; /* for PERROR */
1003 if (stat (name
, &sbuf
) == -1)
1007 sbuf
.st_mode
|= 0111 & ~um
;
1008 if (chmod (name
, sbuf
.st_mode
) == -1)
1013 #ifndef COFF_BSD_SYMBOLS
1016 * If the COFF file contains a symbol table and a line number section,
1017 * then any auxiliary entries that have values for x_lnnoptr must
1018 * be adjusted by the amount that the line number section has moved
1019 * in the file (bias computed in make_hdr). The #@$%&* designers of
1020 * the auxiliary entry structures used the absolute file offsets for
1021 * the line number entry rather than an offset from the start of the
1022 * line number section!
1024 * When I figure out how to scan through the symbol table and pick out
1025 * the auxiliary entries that need adjustment, this routine will
1026 * be fixed. As it is now, all such entries are wrong and sdb
1027 * will complain. Fred Fish, UniSoft Systems Inc.
1030 /* This function is probably very slow. Instead of reopening the new
1031 file for input and output it should copy from the old to the new
1032 using the two descriptors already open (WRITEDESC and READDESC).
1033 Instead of reading one small structure at a time it should use
1034 a reasonable size buffer. But I don't have time to work on such
1035 things, so I am installing it as submitted to me. -- RMS. */
1037 adjust_lnnoptrs (writedesc
, readdesc
, new_name
)
1044 #if defined (amdahl_uts) || defined (pfa)
1048 struct syment symentry
;
1049 union auxent auxentry
;
1052 if (!lnnoptr
|| !f_hdr
.f_symptr
)
1056 if ((new = writedesc
) < 0)
1058 if ((new = open (new_name
, 2)) < 0)
1065 lseek (new, f_hdr
.f_symptr
, 0);
1066 for (nsyms
= 0; nsyms
< f_hdr
.f_nsyms
; nsyms
++)
1068 read (new, &symentry
, SYMESZ
);
1069 if (symentry
.n_numaux
)
1071 read (new, &auxentry
, AUXESZ
);
1073 if (ISFCN (symentry
.n_type
) || symentry
.n_type
== 0x2400)
1075 auxentry
.x_sym
.x_fcnary
.x_fcn
.x_lnnoptr
+= bias
;
1076 lseek (new, -AUXESZ
, 1);
1077 write (new, &auxentry
, AUXESZ
);
1087 #endif /* COFF_BSD_SYMBOLS */
1091 #endif /* not CANNOT_UNEXEC */
1093 #endif /* not CANNOT_DUMP */