1 /* Copyright (C) 1985, 1986, 1987, 1988 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 1, 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 */
182 /* Define getpagesize () if the system does not.
183 Note that this may depend on symbols defined in a.out.h
185 #include "getpagesize.h"
187 #ifndef makedev /* Try to detect types.h already loaded */
188 #include <sys/types.h>
191 #include <sys/stat.h>
194 extern char *start_of_text (); /* Start of text */
195 extern char *start_of_data (); /* Start of initialized data */
198 static long block_copy_start
; /* Old executable start point */
199 static struct filehdr f_hdr
; /* File header */
200 static struct aouthdr f_ohdr
; /* Optional file header (a.out) */
201 long bias
; /* Bias to add for growth */
202 long lnnoptr
; /* Pointer to line-number info within file */
203 #define SYMS_START block_copy_start
205 static long text_scnptr
;
206 static long data_scnptr
;
210 extern char *sbrk ();
212 #define SYMS_START ((long) N_SYMOFF (ohdr))
214 /* Some machines override the structure name for an a.out header. */
215 #ifndef EXEC_HDR_TYPE
216 #define EXEC_HDR_TYPE struct exec
221 #define MY_ID HP9000S200_ID
225 #endif /* no HP9000S200_ID */
226 static MAGIC OLDMAGIC
= {MY_ID
, SHARE_MAGIC
};
227 static MAGIC NEWMAGIC
= {MY_ID
, DEMAND_MAGIC
};
228 #define N_TXTOFF(x) TEXT_OFFSET(x)
229 #define N_SYMOFF(x) LESYM_OFFSET(x)
230 static EXEC_HDR_TYPE hdr
, ohdr
;
234 #if defined (USG) && !defined (IBMAIX) && !defined (IRIS) && !defined (COFF_ENCAPSULATE)
235 static struct bhdr hdr
, ohdr
;
236 #define a_magic fmagic
241 #define a_trsize rtsize
242 #define a_drsize rdsize
243 #define a_entry entry
244 #define N_BADMAG(x) \
245 (((x).fmagic)!=OMAGIC && ((x).fmagic)!=NMAGIC &&\
246 ((x).fmagic)!=FMAGIC && ((x).fmagic)!=IMAGIC)
247 #define NEWMAGIC FMAGIC
248 #else /* IRIS or IBMAIX or not USG */
249 static EXEC_HDR_TYPE hdr
, ohdr
;
250 #define NEWMAGIC ZMAGIC
251 #endif /* IRIS or IBMAIX not USG */
252 #endif /* not HPUX */
254 static int unexec_text_start
;
255 static int unexec_data_start
;
257 #ifdef COFF_ENCAPSULATE
258 /* coffheader is defined in the GNU a.out.encap.h file. */
259 struct coffheader coffheader
;
262 #endif /* not COFF */
266 /* Correct an int which is the bit pattern of a pointer to a byte
267 into an int which is the number of a byte.
268 This is a no-op on ordinary machines, but not on all. */
270 #ifndef ADDR_CORRECT /* Let m-*.h files override this definition */
271 #define ADDR_CORRECT(x) ((char *)(x) - (char*)0)
277 report_error (file
, fd
)
283 error ("Failure operating on %s\n", file
);
287 #define ERROR0(msg) report_error_1 (new, msg, 0, 0); return -1
288 #define ERROR1(msg,x) report_error_1 (new, msg, x, 0); return -1
289 #define ERROR2(msg,x,y) report_error_1 (new, msg, x, y); return -1
292 report_error_1 (fd
, msg
, a1
, a2
)
301 fprintf (stderr
, msg
, a1
, a2
);
302 fprintf (stderr
, "\n");
306 static int make_hdr ();
307 static int copy_text_and_data ();
308 static int copy_sym ();
309 static void mark_x ();
311 /* ****************************************************************
316 unexec (new_name
, a_name
, data_start
, bss_start
, entry_address
)
317 char *new_name
, *a_name
;
318 unsigned data_start
, bss_start
, entry_address
;
322 if (a_name
&& (a_out
= open (a_name
, 0)) < 0)
326 if ((new = creat (new_name
, 0666)) < 0)
331 if (make_hdr (new, a_out
, data_start
, bss_start
, entry_address
, a_name
, new_name
) < 0
332 || copy_text_and_data (new, a_out
) < 0
333 || copy_sym (new, a_out
, a_name
, new_name
) < 0
335 #ifndef COFF_BSD_SYMBOLS
336 || adjust_lnnoptrs (new, a_out
, new_name
) < 0
342 /* unlink (new_name); /* Failed, unlink new a.out */
353 /* ****************************************************************
356 * Make the header in the new a.out from the header in core.
357 * Modify the text and data sizes.
360 make_hdr (new, a_out
, data_start
, bss_start
, entry_address
, a_name
, new_name
)
362 unsigned data_start
, bss_start
, entry_address
;
368 auto struct scnhdr f_thdr
; /* Text section header */
369 auto struct scnhdr f_dhdr
; /* Data section header */
370 auto struct scnhdr f_bhdr
; /* Bss section header */
371 auto struct scnhdr scntemp
; /* Temporary section header */
374 #ifdef USG_SHARED_LIBRARIES
375 extern unsigned int bss_end
;
377 unsigned int bss_end
;
380 pagemask
= getpagesize () - 1;
382 /* Adjust text/data boundary. */
384 data_start
= (int) start_of_data ();
385 #else /* not NO_REMAP */
387 data_start
= (int) start_of_data ();
388 #endif /* not NO_REMAP */
389 data_start
= ADDR_CORRECT (data_start
);
392 data_start
= data_start
& ~SEGMENT_MASK
; /* (Down) to segment boundary. */
394 data_start
= data_start
& ~pagemask
; /* (Down) to page boundary. */
397 bss_end
= ADDR_CORRECT (sbrk (0)) + pagemask
;
398 bss_end
&= ~ pagemask
;
400 /* Adjust data/bss boundary. */
403 bss_start
= (ADDR_CORRECT (bss_start
) + pagemask
);
404 /* (Up) to page bdry. */
405 bss_start
&= ~ pagemask
;
406 if (bss_start
> bss_end
)
408 ERROR1 ("unexec: Specified bss_start (%u) is past end of program",
415 if (data_start
> bss_start
) /* Can't have negative data size. */
417 ERROR2 ("unexec: data_start (%u) can't be greater than bss_start (%u)",
418 data_start
, bss_start
);
422 /* Salvage as much info from the existing file as possible */
425 if (read (a_out
, &f_hdr
, sizeof (f_hdr
)) != sizeof (f_hdr
))
429 block_copy_start
+= sizeof (f_hdr
);
430 if (f_hdr
.f_opthdr
> 0)
432 if (read (a_out
, &f_ohdr
, sizeof (f_ohdr
)) != sizeof (f_ohdr
))
436 block_copy_start
+= sizeof (f_ohdr
);
438 /* Loop through section headers, copying them in */
439 for (scns
= f_hdr
.f_nscns
; scns
> 0; scns
--) {
440 if (read (a_out
, &scntemp
, sizeof (scntemp
)) != sizeof (scntemp
))
444 if (scntemp
.s_scnptr
> 0L)
446 if (block_copy_start
< scntemp
.s_scnptr
+ scntemp
.s_size
)
447 block_copy_start
= scntemp
.s_scnptr
+ scntemp
.s_size
;
449 if (strcmp (scntemp
.s_name
, ".text") == 0)
453 else if (strcmp (scntemp
.s_name
, ".data") == 0)
457 else if (strcmp (scntemp
.s_name
, ".bss") == 0)
465 ERROR0 ("can't build a COFF file from scratch yet");
468 /* Now we alter the contents of all the f_*hdr variables
469 to correspond to what we want to dump. */
471 #ifdef USG_SHARED_LIBRARIES
473 /* The amount of data we're adding to the file is distance from the
474 * end of the original .data space to the current end of the .data
478 bias
= bss_end
- (f_ohdr
.data_start
+ f_dhdr
.s_size
);
482 f_hdr
.f_flags
|= (F_RELFLG
| F_EXEC
);
487 f_ohdr
.magic
= EXEC_MAGIC
;
490 f_ohdr
.text_start
= (long) start_of_text ();
491 f_ohdr
.tsize
= data_start
- f_ohdr
.text_start
;
492 f_ohdr
.data_start
= data_start
;
493 #endif /* NO_REMAP */
494 f_ohdr
.dsize
= bss_start
- f_ohdr
.data_start
;
495 f_ohdr
.bsize
= bss_end
- bss_start
;
496 #ifndef KEEP_OLD_TEXT_SCNPTR
497 /* On some machines, the old values are right.
498 ??? Maybe on all machines with NO_REMAP. */
499 f_thdr
.s_size
= f_ohdr
.tsize
;
500 f_thdr
.s_scnptr
= sizeof (f_hdr
) + sizeof (f_ohdr
);
501 f_thdr
.s_scnptr
+= (f_hdr
.f_nscns
) * (sizeof (f_thdr
));
502 #endif /* KEEP_OLD_TEXT_SCNPTR */
503 #ifdef ADJUST_TEXT_SCNHDR_SIZE
504 /* On some machines, `text size' includes all headers. */
505 f_thdr
.s_size
-= f_thdr
.s_scnptr
;
506 #endif /* ADJUST_TEST_SCNHDR_SIZE */
507 lnnoptr
= f_thdr
.s_lnnoptr
;
508 #ifdef SECTION_ALIGNMENT
509 /* Some systems require special alignment
510 of the sections in the file itself. */
512 = (f_thdr
.s_scnptr
+ SECTION_ALIGNMENT
) & ~SECTION_ALIGNMENT
;
513 #endif /* SECTION_ALIGNMENT */
515 f_thdr
.s_scnptr
= 0xd0;
517 text_scnptr
= f_thdr
.s_scnptr
;
518 #ifdef ADJUST_TEXTBASE
519 text_scnptr
= sizeof (f_hdr
) + sizeof (f_ohdr
) + (f_hdr
.f_nscns
) * (sizeof (f_thdr
));
521 #ifndef KEEP_OLD_PADDR
522 f_dhdr
.s_paddr
= f_ohdr
.data_start
;
523 #endif /* KEEP_OLD_PADDR */
524 f_dhdr
.s_vaddr
= f_ohdr
.data_start
;
525 f_dhdr
.s_size
= f_ohdr
.dsize
;
526 f_dhdr
.s_scnptr
= f_thdr
.s_scnptr
+ f_thdr
.s_size
;
527 #ifdef SECTION_ALIGNMENT
528 /* Some systems require special alignment
529 of the sections in the file itself. */
531 = (f_dhdr
.s_scnptr
+ SECTION_ALIGNMENT
) & ~SECTION_ALIGNMENT
;
532 #endif /* SECTION_ALIGNMENT */
533 #ifdef DATA_SECTION_ALIGNMENT
534 /* Some systems require special alignment
535 of the data section only. */
537 = (f_dhdr
.s_scnptr
+ DATA_SECTION_ALIGNMENT
) & ~DATA_SECTION_ALIGNMENT
;
538 #endif /* DATA_SECTION_ALIGNMENT */
539 data_scnptr
= f_dhdr
.s_scnptr
;
540 #ifndef KEEP_OLD_PADDR
541 f_bhdr
.s_paddr
= f_ohdr
.data_start
+ f_ohdr
.dsize
;
542 #endif /* KEEP_OLD_PADDR */
543 f_bhdr
.s_vaddr
= f_ohdr
.data_start
+ f_ohdr
.dsize
;
544 f_bhdr
.s_size
= f_ohdr
.bsize
;
545 f_bhdr
.s_scnptr
= 0L;
546 #ifndef USG_SHARED_LIBRARIES
547 bias
= f_dhdr
.s_scnptr
+ f_dhdr
.s_size
- block_copy_start
;
550 if (f_hdr
.f_symptr
> 0L)
552 f_hdr
.f_symptr
+= bias
;
555 if (f_thdr
.s_lnnoptr
> 0L)
557 f_thdr
.s_lnnoptr
+= bias
;
560 #ifdef ADJUST_EXEC_HEADER
562 #endif /* ADJUST_EXEC_HEADER */
564 if (write (new, &f_hdr
, sizeof (f_hdr
)) != sizeof (f_hdr
))
569 if (write (new, &f_ohdr
, sizeof (f_ohdr
)) != sizeof (f_ohdr
))
574 #ifndef USG_SHARED_LIBRARIES
576 if (write (new, &f_thdr
, sizeof (f_thdr
)) != sizeof (f_thdr
))
581 if (write (new, &f_dhdr
, sizeof (f_dhdr
)) != sizeof (f_dhdr
))
586 if (write (new, &f_bhdr
, sizeof (f_bhdr
)) != sizeof (f_bhdr
))
591 #else /* USG_SHARED_LIBRARIES */
593 /* The purpose of this code is to write out the new file's section
596 * Scan through the original file's sections. If the encountered
597 * section is one we know (.text, .data or .bss), write out the
598 * correct header. If it is a section we do not know (such as
599 * .lib), adjust the address of where the section data is in the
600 * file, and write out the header.
602 * If any section preceeds .text or .data in the file, this code
603 * will not adjust the file pointer for that section correctly.
606 lseek (a_out
, sizeof (f_hdr
) + sizeof (f_ohdr
), 0);
608 for (scns
= f_hdr
.f_nscns
; scns
> 0; scns
--)
610 if (read (a_out
, &scntemp
, sizeof (scntemp
)) != sizeof (scntemp
))
613 if (!strcmp (scntemp
.s_name
, f_thdr
.s_name
)) /* .text */
615 if (write (new, &f_thdr
, sizeof (f_thdr
)) != sizeof (f_thdr
))
618 else if (!strcmp (scntemp
.s_name
, f_dhdr
.s_name
)) /* .data */
620 if (write (new, &f_dhdr
, sizeof (f_dhdr
)) != sizeof (f_dhdr
))
623 else if (!strcmp (scntemp
.s_name
, f_bhdr
.s_name
)) /* .bss */
625 if (write (new, &f_bhdr
, sizeof (f_bhdr
)) != sizeof (f_bhdr
))
630 if (scntemp
.s_scnptr
)
631 scntemp
.s_scnptr
+= bias
;
632 if (write (new, &scntemp
, sizeof (scntemp
)) != sizeof (scntemp
))
636 #endif /* USG_SHARED_LIBRARIES */
640 #else /* if not COFF */
642 /* Get symbol table info from header of a.out file if given one. */
645 #ifdef COFF_ENCAPSULATE
646 if (read (a_out
, &coffheader
, sizeof coffheader
) != sizeof coffheader
)
650 if (coffheader
.f_magic
!= COFF_MAGIC
)
652 ERROR1("%s doesn't have legal coff magic number\n", a_name
);
655 if (read (a_out
, &ohdr
, sizeof hdr
) != sizeof hdr
)
662 ERROR1 ("invalid magic number in %s", a_name
);
668 #ifdef COFF_ENCAPSULATE
669 /* We probably could without too much trouble. The code is in gld
670 * but I don't have that much time or incentive.
672 ERROR0 ("can't build a COFF file from scratch yet");
674 bzero (hdr
, sizeof hdr
);
678 unexec_text_start
= (long) start_of_text ();
679 unexec_data_start
= data_start
;
681 /* Machine-dependent fixup for header, or maybe for unexec_text_start */
682 #ifdef ADJUST_EXEC_HEADER
684 #endif /* ADJUST_EXEC_HEADER */
688 if (entry_address
!= 0)
689 hdr
.a_entry
= entry_address
;
691 hdr
.a_bss
= bss_end
- bss_start
;
692 hdr
.a_data
= bss_start
- data_start
;
694 hdr
.a_text
= ohdr
.a_text
;
695 #else /* not NO_REMAP */
696 hdr
.a_text
= data_start
- unexec_text_start
;
699 hdr
.a_text
+= A_TEXT_OFFSET (ohdr
);
702 #endif /* not NO_REMAP */
704 #ifdef COFF_ENCAPSULATE
705 /* We are encapsulating BSD format within COFF format. */
707 struct coffscn
*tp
, *dp
, *bp
;
708 tp
= &coffheader
.scns
[0];
709 dp
= &coffheader
.scns
[1];
710 bp
= &coffheader
.scns
[2];
711 tp
->s_size
= hdr
.a_text
+ sizeof(struct exec
);
712 dp
->s_paddr
= data_start
;
713 dp
->s_vaddr
= data_start
;
714 dp
->s_size
= hdr
.a_data
;
715 bp
->s_paddr
= dp
->s_vaddr
+ dp
->s_size
;
716 bp
->s_vaddr
= bp
->s_paddr
;
717 bp
->s_size
= hdr
.a_bss
;
718 coffheader
.tsize
= tp
->s_size
;
719 coffheader
.dsize
= dp
->s_size
;
720 coffheader
.bsize
= bp
->s_size
;
721 coffheader
.text_start
= tp
->s_vaddr
;
722 coffheader
.data_start
= dp
->s_vaddr
;
724 if (write (new, &coffheader
, sizeof coffheader
) != sizeof coffheader
)
728 #endif /* COFF_ENCAPSULATE */
730 if (write (new, &hdr
, sizeof hdr
) != sizeof hdr
)
736 hdr
.a_text
-= A_TEXT_OFFSET (ohdr
);
741 #endif /* not COFF */
744 /* ****************************************************************
747 * Copy the text and data segments from memory to the new a.out
750 copy_text_and_data (new, a_out
)
758 #ifdef USG_SHARED_LIBRARIES
761 struct scnhdr scntemp
; /* Temporary section header */
763 /* The purpose of this code is to write out the new file's section
766 * Step through the section table. If we know the section (.text,
767 * .data) do the appropriate thing. Otherwise, if the section has
768 * no allocated space in the file (.bss), do nothing. Otherwise,
769 * the section has space allocated in the file, and is not a section
770 * we know. So just copy it.
773 lseek (a_out
, sizeof (struct filehdr
) + sizeof (struct aouthdr
), 0);
775 for (scns
= f_hdr
.f_nscns
; scns
> 0; scns
--)
777 if (read (a_out
, &scntemp
, sizeof (scntemp
)) != sizeof (scntemp
))
780 if (!strcmp (scntemp
.s_name
, ".text"))
782 lseek (new, (long) text_scnptr
, 0);
783 ptr
= (char *) f_ohdr
.text_start
;
784 end
= ptr
+ f_ohdr
.tsize
;
785 write_segment (new, ptr
, end
);
787 else if (!strcmp (scntemp
.s_name
, ".data"))
789 lseek (new, (long) data_scnptr
, 0);
790 ptr
= (char *) f_ohdr
.data_start
;
791 end
= ptr
+ f_ohdr
.dsize
;
792 write_segment (new, ptr
, end
);
794 else if (!scntemp
.s_scnptr
)
795 ; /* do nothing - no data for this section */
800 long old_a_out_ptr
= lseek (a_out
, 0, 1);
802 lseek (a_out
, scntemp
.s_scnptr
, 0);
803 for (size
= scntemp
.s_size
; size
> 0; size
-= sizeof (page
))
805 n
= size
> sizeof (page
) ? sizeof (page
) : size
;
806 if (read (a_out
, page
, n
) != n
|| write (new, page
, n
) != n
)
809 lseek (a_out
, old_a_out_ptr
, 0);
813 #else /* COFF, but not USG_SHARED_LIBRARIES */
815 lseek (new, (long) text_scnptr
, 0);
816 ptr
= (char *) f_ohdr
.text_start
;
817 #ifdef HEADER_INCL_IN_TEXT
818 /* For Gould UTX/32, text starts after headers */
819 ptr
= (char *) (ptr
+ text_scnptr
);
820 #endif /* HEADER_INCL_IN_TEXT */
821 end
= ptr
+ f_ohdr
.tsize
;
822 write_segment (new, ptr
, end
);
824 lseek (new, (long) data_scnptr
, 0);
825 ptr
= (char *) f_ohdr
.data_start
;
826 end
= ptr
+ f_ohdr
.dsize
;
827 write_segment (new, ptr
, end
);
829 #endif /* USG_SHARED_LIBRARIES */
831 #else /* if not COFF */
833 /* Some machines count the header as part of the text segment.
834 That is to say, the header appears in core
835 just before the address that start_of_text () returns.
836 For them, N_TXTOFF is the place where the header goes.
837 We must adjust the seek to the place after the header.
838 Note that at this point hdr.a_text does *not* count
839 the extra A_TEXT_OFFSET bytes, only the actual bytes of code. */
842 lseek (new, (long) A_TEXT_SEEK (hdr
), 0);
844 lseek (new, (long) N_TXTOFF (hdr
), 0);
845 #endif /* no A_TEXT_SEEK */
847 ptr
= (char *) unexec_text_start
;
848 end
= ptr
+ hdr
.a_text
;
849 write_segment (new, ptr
, end
);
851 ptr
= (char *) unexec_data_start
;
852 end
= ptr
+ hdr
.a_data
;
853 /* This lseek is certainly incorrect when A_TEXT_OFFSET
854 and I believe it is a no-op otherwise.
855 Let's see if its absence ever fails. */
856 /* lseek (new, (long) N_TXTOFF (hdr) + hdr.a_text, 0); */
857 write_segment (new, ptr
, end
);
859 #endif /* not COFF */
864 write_segment (new, ptr
, end
)
866 register char *ptr
, *end
;
868 register int i
, nwrite
, ret
;
873 bzero (zeros
, sizeof zeros
);
875 for (i
= 0; ptr
< end
;)
877 /* distance to next multiple of 128. */
878 nwrite
= (((int) ptr
+ 128) & -128) - (int) ptr
;
879 /* But not beyond specified end. */
880 if (nwrite
> end
- ptr
) nwrite
= end
- ptr
;
881 ret
= write (new, ptr
, nwrite
);
882 /* If write gets a page fault, it means we reached
883 a gap between the old text segment and the old data segment.
884 This gap has probably been remapped into part of the text segment.
885 So write zeros for it. */
886 if (ret
== -1 && errno
== EFAULT
)
887 write (new, zeros
, nwrite
);
888 else if (nwrite
!= ret
)
891 "unexec write failure: addr 0x%x, fileno %d, size 0x%x, wrote 0x%x, errno %d",
892 ptr
, new, nwrite
, ret
, errno
);
900 /* ****************************************************************
903 * Copy the relocation information and symbol table from the a.out to the new
906 copy_sym (new, a_out
, a_name
, new_name
)
908 char *a_name
, *new_name
;
917 if (SYMS_START
== 0L)
922 if (lnnoptr
) /* if there is line number info */
923 lseek (a_out
, lnnoptr
, 0); /* start copying from there */
926 lseek (a_out
, SYMS_START
, 0); /* Position a.out to symtab. */
928 while ((n
= read (a_out
, page
, sizeof page
)) > 0)
930 if (write (new, page
, n
) != n
)
942 /* ****************************************************************
945 * After succesfully building the new a.out, mark it executable
953 int new = 0; /* for PERROR */
957 if (stat (name
, &sbuf
) == -1)
961 sbuf
.st_mode
|= 0111 & ~um
;
962 if (chmod (name
, sbuf
.st_mode
) == -1)
967 #ifndef COFF_BSD_SYMBOLS
970 * If the COFF file contains a symbol table and a line number section,
971 * then any auxiliary entries that have values for x_lnnoptr must
972 * be adjusted by the amount that the line number section has moved
973 * in the file (bias computed in make_hdr). The #@$%&* designers of
974 * the auxiliary entry structures used the absolute file offsets for
975 * the line number entry rather than an offset from the start of the
976 * line number section!
978 * When I figure out how to scan through the symbol table and pick out
979 * the auxiliary entries that need adjustment, this routine will
980 * be fixed. As it is now, all such entries are wrong and sdb
981 * will complain. Fred Fish, UniSoft Systems Inc.
984 /* This function is probably very slow. Instead of reopening the new
985 file for input and output it should copy from the old to the new
986 using the two descriptors already open (WRITEDESC and READDESC).
987 Instead of reading one small structure at a time it should use
988 a reasonable size buffer. But I don't have time to work on such
989 things, so I am installing it as submitted to me. -- RMS. */
991 adjust_lnnoptrs (writedesc
, readdesc
, new_name
)
1002 struct syment symentry
;
1003 union auxent auxentry
;
1006 if (!lnnoptr
|| !f_hdr
.f_symptr
)
1009 if ((new = open (new_name
, 2)) < 0)
1015 lseek (new, f_hdr
.f_symptr
, 0);
1016 for (nsyms
= 0; nsyms
< f_hdr
.f_nsyms
; nsyms
++)
1018 read (new, &symentry
, SYMESZ
);
1019 if (symentry
.n_numaux
)
1021 read (new, &auxentry
, AUXESZ
);
1023 if (ISFCN (symentry
.n_type
)) {
1024 auxentry
.x_sym
.x_fcnary
.x_fcn
.x_lnnoptr
+= bias
;
1025 lseek (new, -AUXESZ
, 1);
1026 write (new, &auxentry
, AUXESZ
);
1033 #endif /* COFF_BSD_SYMBOLS */
1037 #endif /* not CANNOT_UNEXEC */
1039 #endif /* not CANNOT_DUMP */