-/* Modified by Andrew.Vignaux@comp.vuw.ac.nz to get it to work :-) */
-
-/* Copyright (C) 1985, 1986, 1987, 1988 Free Software Foundation, Inc.
+/* Dump an executable image.
+ Copyright (C) 1985, 1986, 1987, 1988, 1999 Free Software Foundation, Inc.
This file is part of GNU Emacs.
what you give them. Help stamp out software-hoarding! */
-/*
- * unexec.c - Convert a running program into an a.out file.
- *
- * Author: Spencer W. Thomas
- * Computer Science Dept.
- * University of Utah
- * Date: Tue Mar 2 1982
- * Modified heavily since then.
+/* Originally based on the COFF unexec.c by Spencer W. Thomas.
*
- * Updated for AIX 4.1.3 by Bill_Mann @ PraxisInt.com, Feb 1996
- * As of AIX 4.1, text, data, and bss are pre-relocated by the binder in
- * such a way that the file can be mapped with code in one segment and
- * data/bss in another segment, without reading or copying the file, by
- * the AIX exec loader. Padding sections are omitted, nevertheless
- * small amounts of 'padding' still occurs between sections in the file.
- * As modified, this code handles both 3.2 and 4.1 conventions.
+ * Subsequently hacked on by
+ * Bill Mann <Bill_Man@praxisint.com>
+ * Andrew Vignaux <Andrew.Vignaux@comp.vuw.ac.nz>
+ * Mike Sperber <sperber@informatik.uni-tuebingen.de>
*
* Synopsis:
* unexec (new_name, a_name, data_start, bss_start, entry_address)
* If a_name is non-NULL, the symbol table will be taken from the given file.
* On some machines, an existing a_name file is required.
*
- * The boundaries within the a.out file may be adjusted with the data_start
- * and bss_start arguments. Either or both may be given as 0 for defaults.
- *
- * Data_start gives the boundary between the text segment and the data
- * segment of the program. The text segment can contain shared, read-only
- * program code and literal data, while the data segment is always unshared
- * and unprotected. Data_start gives the lowest unprotected address.
- * The value you specify may be rounded down to a suitable boundary
- * as required by the machine you are using.
+ * data_start and entry_address are ignored.
*
- * Specifying zero for data_start means the boundary between text and data
- * should not be the same as when the program was loaded.
- * If NO_REMAP is defined, the argument data_start is ignored and the
- * segment boundaries are never changed.
- *
- * Bss_start indicates how much of the data segment is to be saved in the
+ * bss_start indicates how much of the data segment is to be saved in the
* a.out file and restored when the program is executed. It gives the lowest
* unsaved address, and is rounded up to a page boundary. The default when 0
* is given assumes that the entire data segment is to be stored, including
* the previous data and bss as well as any additional storage allocated with
- * break (2).
- *
- * The new file is set up to start at entry_address.
- *
- * If you make improvements I'd like to get them too.
- * harpo!utah-cs!thomas, thomas@Utah-20
+ * sbrk(2).
*
*/
-/* There are several compilation parameters affecting unexec:
-
-* COFF
-
-Define this if your system uses COFF for executables.
-Otherwise we assume you use Berkeley format.
-
-* NO_REMAP
-
-Define this if you do not want to try to save Emacs's pure data areas
-as part of the text segment.
-
-Saving them as text is good because it allows users to share more.
-
-However, on machines that locate the text area far from the data area,
-the boundary cannot feasibly be moved. Such machines require
-NO_REMAP.
-
-Also, remapping can cause trouble with the built-in startup routine
-/lib/crt0.o, which defines `environ' as an initialized variable.
-Dumping `environ' as pure does not work! So, to use remapping,
-you must write a startup routine for your machine in Emacs's crt0.c.
-If NO_REMAP is defined, Emacs uses the system's crt0.o.
-
-* SECTION_ALIGNMENT
-
-Some machines that use COFF executables require that each section
-start on a certain boundary *in the COFF file*. Such machines should
-define SECTION_ALIGNMENT to a mask of the low-order bits that must be
-zero on such a boundary. This mask is used to control padding between
-segments in the COFF file.
-
-If SECTION_ALIGNMENT is not defined, the segments are written
-consecutively with no attempt at alignment. This is right for
-unmodified system V.
-
-* SEGMENT_MASK
-
-Some machines require that the beginnings and ends of segments
-*in core* be on certain boundaries. For most machines, a page
-boundary is sufficient. That is the default. When a larger
-boundary is needed, define SEGMENT_MASK to a mask of
-the bits that must be zero on such a boundary.
-
-* A_TEXT_OFFSET(HDR)
-
-Some machines count the a.out header as part of the size of the text
-segment (a_text); they may actually load the header into core as the
-first data in the text segment. Some have additional padding between
-the header and the real text of the program that is counted in a_text.
-
-For these machines, define A_TEXT_OFFSET(HDR) to examine the header
-structure HDR and return the number of bytes to add to `a_text'
-before writing it (above and beyond the number of bytes of actual
-program text). HDR's standard fields are already correct, except that
-this adjustment to the `a_text' field has not yet been made;
-thus, the amount of offset can depend on the data in the file.
-
-* A_TEXT_SEEK(HDR)
-
-If defined, this macro specifies the number of bytes to seek into the
-a.out file before starting to write the text segment.a
-
-* EXEC_MAGIC
-
-For machines using COFF, this macro, if defined, is a value stored
-into the magic number field of the output file.
-
-* ADJUST_EXEC_HEADER
-
-This macro can be used to generate statements to adjust or
-initialize nonstandard fields in the file header
-
-* ADDR_CORRECT(ADDR)
-
-Macro to correct an int which is the bit pattern of a pointer to a byte
-into an int which is the number of a byte.
-
-This macro has a default definition which is usually right.
-This default definition is a no-op on most machines (where a
-pointer looks like an int) but not on all machines.
-
-*/
-
-#define XCOFF
-#define COFF
-#define NO_REMAP
-
#ifndef emacs
#define PERROR(arg) perror (arg); return -1
#else
*/
#include "getpagesize.h"
-#ifndef makedev /* Try to detect types.h already loaded */
#include <sys/types.h>
-#endif
#include <stdio.h>
#include <sys/stat.h>
#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
-extern char *start_of_text (); /* Start of text */
-extern char *start_of_data (); /* Start of initialized data */
+extern char *start_of_text (void); /* Start of text */
+extern char *start_of_data (void); /* Start of initialized data */
extern int _data;
-extern int _edata;
extern int _text;
-extern int _etext;
-extern int _end;
-#ifdef COFF
-#ifndef USG
-#ifndef STRIDE
-#ifndef UMAX
-#ifndef sun386
-/* I have a suspicion that these are turned off on all systems
- and can be deleted. Try it in version 19. */
+
#include <filehdr.h>
#include <aouthdr.h>
#include <scnhdr.h>
#include <syms.h>
-#endif /* not sun386 */
-#endif /* not UMAX */
-#endif /* Not STRIDE */
-#endif /* not USG */
+
static struct filehdr f_hdr; /* File header */
static struct aouthdr f_ohdr; /* Optional file header (a.out) */
-long bias; /* Bias to add for growth */
-long lnnoptr; /* Pointer to line-number info within file */
+static long bias; /* Bias to add for growth */
+static long lnnoptr; /* Pointer to line-number info within file */
static long text_scnptr;
static long data_scnptr;
-#ifdef XCOFF
#define ALIGN(val, pwr) (((val) + ((1L<<(pwr))-1)) & ~((1L<<(pwr))-1))
static long load_scnptr;
static long orig_load_scnptr;
static long orig_data_scnptr;
-#endif
-static ulong data_st; /* start of data area written out */
+static int unrelocate_symbols (int, int, char *, char *);
#ifndef MAX_SECTIONS
#define MAX_SECTIONS 10
#endif
-#endif /* COFF */
+static int adjust_lnnoptrs (int, int, char *);
static int pagemask;
#ifdef emacs
#include "lisp.h"
-static
-report_error (file, fd)
- char *file;
- int fd;
+static void
+report_error (char *file, int fd)
{
if (fd)
close (fd);
#define ERROR1(msg,x) report_error_1 (new, msg, x, 0); return -1
#define ERROR2(msg,x,y) report_error_1 (new, msg, x, y); return -1
-static
-report_error_1 (fd, msg, a1, a2)
- int fd;
- char *msg;
- int a1, a2;
+static void
+report_error_1 (int fd, char *msg, int a1, int a2)
{
close (fd);
#ifdef emacs
#endif
}
-static int make_hdr ();
-static void mark_x ();
-static int copy_text_and_data ();
-static int copy_sym ();
+static int make_hdr (int, int, unsigned, unsigned, unsigned, char *, char *);
+static void mark_x (char *);
+static int copy_text_and_data (int);
+static int copy_sym (int, int, char *, char *);
+static void write_segment (int, char *, char *);
\f
/* ****************************************************************
* unexec
*
* driving logic.
*/
-unexec (new_name, a_name, data_start, bss_start, entry_address)
- char *new_name, *a_name;
- unsigned data_start, bss_start, entry_address;
+int unexec (char *new_name, char *a_name,
+ uintptr_t data_start,
+ uintptr_t bss_start,
+ uintptr_t entry_address)
{
- int new, a_out = -1;
+ int new = -1, a_out = -1;
- if (a_name && (a_out = open (a_name, 0)) < 0)
+ if (a_name && (a_out = open (a_name, O_RDONLY)) < 0)
{
PERROR (a_name);
}
{
PERROR (new_name);
}
- if (make_hdr (new,a_out,data_start,bss_start,entry_address,a_name,new_name) < 0
+ if (make_hdr (new, a_out,
+ data_start, bss_start,
+ entry_address,
+ a_name, new_name) < 0
|| copy_text_and_data (new) < 0
|| copy_sym (new, a_out, a_name, new_name) < 0
-#ifdef COFF
|| adjust_lnnoptrs (new, a_out, new_name) < 0
-#endif
-#ifdef XCOFF
- || unrelocate_symbols (new, a_out, a_name, new_name) < 0
-#endif
- )
+ || unrelocate_symbols (new, a_out, a_name, new_name) < 0)
{
close (new);
- /* unlink (new_name); /* Failed, unlink new a.out */
return -1;
}
* Modify the text and data sizes.
*/
static int
-make_hdr (new, a_out, data_start, bss_start, entry_address, a_name, new_name)
- int new, a_out;
- unsigned data_start, bss_start, entry_address;
- char *a_name;
- char *new_name;
+make_hdr (int new, int a_out,
+ unsigned data_start, unsigned bss_start,
+ unsigned entry_address,
+ char *a_name, char *new_name)
{
- register int scns;
+ int scns;
unsigned int bss_end;
struct scnhdr section[MAX_SECTIONS];
pagemask = getpagesize () - 1;
/* Adjust text/data boundary. */
-#ifdef NO_REMAP
data_start = (long) start_of_data ();
-#endif /* NO_REMAP */
data_start = ADDR_CORRECT (data_start);
-#ifdef SEGMENT_MASK
- data_start = data_start & ~SEGMENT_MASK; /* (Down) to segment boundary. */
-#else
data_start = data_start & ~pagemask; /* (Down) to page boundary. */
-#endif
-
bss_end = ADDR_CORRECT (sbrk (0)) + pagemask;
bss_end &= ~ pagemask;
data_start, bss_start);
}
-#ifdef COFF
/* Salvage as much info from the existing file as possible */
f_thdr = NULL; f_dhdr = NULL; f_bhdr = NULL;
f_lhdr = NULL; f_tchdr = NULL; f_dbhdr = NULL; f_xhdr = NULL;
if (f_thdr == 0)
{
- ERROR1 ("unexec: couldn't find \"%s\" section", _TEXT);
+ ERROR1 ("unexec: couldn't find \"%s\" section", (int) _TEXT);
}
if (f_dhdr == 0)
{
- ERROR1 ("unexec: couldn't find \"%s\" section", _DATA);
+ ERROR1 ("unexec: couldn't find \"%s\" section", (int) _DATA);
}
if (f_bhdr == 0)
{
- ERROR1 ("unexec: couldn't find \"%s\" section", _BSS);
+ ERROR1 ("unexec: couldn't find \"%s\" section", (int) _BSS);
}
}
else
we only update it enough to fake out the exec-time loader. */
f_hdr.f_flags |= (F_RELFLG | F_EXEC);
-#ifdef EXEC_MAGIC
- f_ohdr.magic = EXEC_MAGIC;
-#endif
-#ifndef NO_REMAP
- f_ohdr.tsize = data_start - f_ohdr.text_start;
- f_ohdr.text_start = (long) start_of_text ();
-#endif
- data_st = f_ohdr.data_start ? f_ohdr.data_start : (ulong) &_data;
- f_ohdr.dsize = bss_start - data_st;
+ f_ohdr.dsize = bss_start - f_ohdr.data_start;
f_ohdr.bsize = bss_end - bss_start;
f_dhdr->s_size = f_ohdr.dsize;
data_scnptr = f_dhdr->s_scnptr;
load_scnptr = f_lhdr ? f_lhdr->s_scnptr : 0;
-#ifdef ADJUST_EXEC_HEADER
- ADJUST_EXEC_HEADER
-#endif /* ADJUST_EXEC_HEADER */
-
if (write (new, &f_hdr, sizeof (f_hdr)) != sizeof (f_hdr))
{
PERROR (new_name);
}
return (0);
-
-#endif /* COFF */
}
\f
/* ****************************************************************
* Copy the text and data segments from memory to the new a.out
*/
static int
-copy_text_and_data (new)
- int new;
+copy_text_and_data (int new)
{
- register char *end;
- register char *ptr;
+ char *end;
+ char *ptr;
- lseek (new, (long) text_scnptr, 0);
+ lseek (new, (long) text_scnptr, SEEK_SET);
ptr = start_of_text () + text_scnptr;
end = ptr + f_ohdr.tsize;
write_segment (new, ptr, end);
- lseek (new, (long) data_scnptr, 0);
- ptr = (char *) data_st;
+ lseek (new, (long) data_scnptr, SEEK_SET);
+ ptr = (char *) f_ohdr.data_start;
end = ptr + f_ohdr.dsize;
write_segment (new, ptr, end);
}
#define UnexBlockSz (1<<12) /* read/write block size */
-write_segment (new, ptr, end)
- int new;
- register char *ptr, *end;
+static void
+write_segment (int new, char *ptr, char *end)
{
- register int i, nwrite, ret;
+ int i, nwrite, ret;
char buf[80];
extern int errno;
char zeros[UnexBlockSz];
So write zeros for it. */
if (ret == -1 && errno == EFAULT)
{
- bzero (zeros, nwrite);
+ memset (zeros, 0, nwrite);
write (new, zeros, nwrite);
}
else if (nwrite != ret)
* Copy the relocation information and symbol table from the a.out to the new
*/
static int
-copy_sym (new, a_out, a_name, new_name)
- int new, a_out;
- char *a_name, *new_name;
+copy_sym (int new, int a_out, char *a_name, char *new_name)
{
char page[UnexBlockSz];
int n;
return 0;
if (lnnoptr && lnnoptr < orig_load_scnptr) /* if there is line number info */
- lseek (a_out, lnnoptr, 0); /* start copying from there */
+ lseek (a_out, lnnoptr, SEEK_SET); /* start copying from there */
else
- lseek (a_out, orig_load_scnptr, 0); /* Position a.out to symtab. */
+ lseek (a_out, orig_load_scnptr, SEEK_SET); /* Position a.out to symtab. */
while ((n = read (a_out, page, sizeof page)) > 0)
{
* After successfully building the new a.out, mark it executable
*/
static void
-mark_x (name)
- char *name;
+mark_x (char *name)
{
struct stat sbuf;
int um;
PERROR (name);
}
\f
-/*
- * If the COFF file contains a symbol table and a line number section,
- * then any auxiliary entries that have values for x_lnnoptr must
- * be adjusted by the amount that the line number section has moved
- * in the file (bias computed in make_hdr). The #@$%&* designers of
- * the auxiliary entry structures used the absolute file offsets for
- * the line number entry rather than an offset from the start of the
- * line number section!
- *
- * When I figure out how to scan through the symbol table and pick out
- * the auxiliary entries that need adjustment, this routine will
- * be fixed. As it is now, all such entries are wrong and sdb
- * will complain. Fred Fish, UniSoft Systems Inc.
- *
- * I believe this is now fixed correctly. Bill Mann
- */
-
-#ifdef COFF
-
-/* This function is probably very slow. Instead of reopening the new
- file for input and output it should copy from the old to the new
- using the two descriptors already open (WRITEDESC and READDESC).
- Instead of reading one small structure at a time it should use
- a reasonable size buffer. But I don't have time to work on such
- things, so I am installing it as submitted to me. -- RMS. */
-
-adjust_lnnoptrs (writedesc, readdesc, new_name)
- int writedesc;
- int readdesc;
- char *new_name;
+static int
+adjust_lnnoptrs (int writedesc, int readdesc, char *new_name)
{
- register int nsyms;
- register int naux;
- register int new;
-#ifdef amdahl_uts
- SYMENT symentry;
- AUXENT auxentry;
-#else
+ int nsyms;
+ int naux;
+ int new;
struct syment symentry;
union auxent auxentry;
-#endif
if (!lnnoptr || !f_hdr.f_symptr)
return 0;
- if ((new = open (new_name, 2)) < 0)
+ if ((new = open (new_name, O_RDWR)) < 0)
{
PERROR (new_name);
return -1;
}
- lseek (new, f_hdr.f_symptr, 0);
+ lseek (new, f_hdr.f_symptr, SEEK_SET);
for (nsyms = 0; nsyms < f_hdr.f_nsyms; nsyms++)
{
read (new, &symentry, SYMESZ);
if (symentry.n_sclass == C_BINCL || symentry.n_sclass == C_EINCL)
{
symentry.n_value += bias;
- lseek (new, -SYMESZ, 1);
+ lseek (new, -SYMESZ, SEEK_CUR);
write (new, &symentry, SYMESZ);
}
&& (symentry.n_sclass == C_EXT || symentry.n_sclass == C_HIDEXT))
{
auxentry.x_sym.x_fcnary.x_fcn.x_lnnoptr += bias;
- lseek (new, -AUXESZ, 1);
+ lseek (new, -AUXESZ, SEEK_CUR);
write (new, &auxentry, AUXESZ);
}
}
}
close (new);
-}
-
-#endif /* COFF */
-#ifdef XCOFF
-
-/* It is probably a false economy to optimise this routine (it used to
- read one LDREL and do do two lseeks per iteration) but the wrath of
- RMS (see above :-) would be too much to bear */
+ return 0;
+}
-unrelocate_symbols (new, a_out, a_name, new_name)
- int new, a_out;
- char *a_name, *new_name;
+static int
+unrelocate_symbols (int new, int a_out, char *a_name, char *new_name)
{
- register int i;
- register int l;
- register LDREL *ldrel;
+ int i;
LDHDR ldhdr;
- LDREL ldrel_buf [20];
+ LDREL ldrel;
ulong t_reloc = (ulong) &_text - f_ohdr.text_start;
+#ifndef ALIGN_DATA_RELOC
+ ulong d_reloc = (ulong) &_data - f_ohdr.data_start;
+#else
+ /* This worked (and was needed) before AIX 4.2.
+ I have no idea why. -- Mike */
ulong d_reloc = (ulong) &_data - ALIGN(f_ohdr.data_start, 2);
+#endif
int * p;
if (load_scnptr == 0)
return 0;
- lseek (a_out, orig_load_scnptr, 0);
+ lseek (a_out, orig_load_scnptr, SEEK_SET);
if (read (a_out, &ldhdr, sizeof (ldhdr)) != sizeof (ldhdr))
{
PERROR (new_name);
#define SYMNDX_TEXT 0
#define SYMNDX_DATA 1
#define SYMNDX_BSS 2
- l = 0;
- for (i = 0; i < ldhdr.l_nreloc; i++, l--, ldrel++)
- {
- if (l == 0) {
- lseek (a_out,
- orig_load_scnptr + LDHDRSZ + LDSYMSZ*ldhdr.l_nsyms + LDRELSZ*i,
- 0);
- l = ldhdr.l_nreloc - i;
- if (l > sizeof (ldrel_buf) / LDRELSZ)
- l = sizeof (ldrel_buf) / LDRELSZ;
+ for (i = 0; i < ldhdr.l_nreloc; i++)
+ {
+ lseek (a_out,
+ orig_load_scnptr + LDHDRSZ + LDSYMSZ*ldhdr.l_nsyms + LDRELSZ*i,
+ SEEK_SET);
- if (read (a_out, ldrel_buf, l * LDRELSZ) != l * LDRELSZ)
- {
- PERROR (a_name);
- }
- ldrel = ldrel_buf;
- }
+ if (read (a_out, &ldrel, LDRELSZ) != LDRELSZ)
+ {
+ PERROR (a_name);
+ }
/* move the BSS loader symbols to the DATA segment */
- if (ldrel->l_symndx == SYMNDX_BSS)
+ if (ldrel.l_symndx == SYMNDX_BSS)
{
- ldrel->l_symndx = SYMNDX_DATA;
+ ldrel.l_symndx = SYMNDX_DATA;
lseek (new,
load_scnptr + LDHDRSZ + LDSYMSZ*ldhdr.l_nsyms + LDRELSZ*i,
- 0);
+ SEEK_SET);
- if (write (new, ldrel, LDRELSZ) != LDRELSZ)
+ if (write (new, &ldrel, LDRELSZ) != LDRELSZ)
{
PERROR (new_name);
}
}
- if (ldrel->l_rsecnm == f_ohdr.o_sndata)
+ if (ldrel.l_rsecnm == f_ohdr.o_sndata)
{
int orig_int;
lseek (a_out,
- orig_data_scnptr + (ldrel->l_vaddr - f_ohdr.data_start), 0);
+ orig_data_scnptr + (ldrel.l_vaddr - f_ohdr.data_start),
+ SEEK_SET);
- if (read (a_out, (void *) &orig_int, sizeof (orig_int)) != sizeof (orig_int))
+ if (read (a_out, (void *) &orig_int, sizeof (orig_int))
+ != sizeof (orig_int))
{
PERROR (a_name);
}
- p = (int *) (ldrel->l_vaddr + d_reloc);
+ p = (int *) (ldrel.l_vaddr + d_reloc);
- switch (ldrel->l_symndx) {
+ switch (ldrel.l_symndx) {
case SYMNDX_TEXT:
orig_int = * p - t_reloc;
break;
if (orig_int != * p)
{
lseek (new,
- data_scnptr + (ldrel->l_vaddr - f_ohdr.data_start), 0);
+ data_scnptr + (ldrel.l_vaddr - f_ohdr.data_start),
+ SEEK_SET);
if (write (new, (void *) &orig_int, sizeof (orig_int))
!= sizeof (orig_int))
{
}
}
}
+ return 0;
}
-#endif /* XCOFF */
HCoop / bpt / emacs.git / blobdiff