xemacs-beta: src/unexec.c comparison

comparison src/unexec.c @ 0:376386a54a3c r19-14

Import from CVS: tag r19-14

author	cvs
date	Mon, 13 Aug 2007 08:45:50 +0200
parents
children	ac2d302a0011

comparison

equal deleted inserted replaced

--1:000000000000
+:376386a54a3c
+/* Copyright (C) 1985, 1986, 1987, 1988, 1992, 1993, 1994
+Free Software Foundation, Inc.
+This file is part of XEmacs.
+XEmacs is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the
+Free Software Foundation; either version 2, or (at your option) any
+later version.
+XEmacs is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+You should have received a copy of the GNU General Public License
+along with XEmacs; see the file COPYING.  If not, write to
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+/* Synched up with: FSF 19.31. */
+/*
+* 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.
+*
+* Synopsis:
+*	unexec (new_name, a_name, data_start, bss_start, entry_address)
+*	char *new_name, *a_name;
+*	unsigned data_start, bss_start, entry_address;
+*
+* Takes a snapshot of the program and makes an a.out format file in the
+* file named by the string argument new_name.
+* 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.
+*
+* 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
+* 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
+*
+*/
+/* Modified to support SysVr3 shared libraries by James Van Artsdalen
+* of Dell Computer Corporation.  james@bigtex.cactus.org.
+*/
+/* There are several compilation parameters affecting unexec:
+* COFF
+Define this if your system uses COFF for executables.
+* COFF_ENCAPSULATE
+Define this if you are using the GNU coff encapsulated a.out format.
+This is closer to a.out than COFF. You should *not* define COFF if
+you define COFF_ENCAPSULATE
+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.
+* 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.
+*/
+#ifndef emacs
+#define PERROR(arg) perror (arg); return -1
+#else
+#define IN_UNEXEC
+#define DONT_ENCAPSULATE /* we include lisp.h so we want to make sure we
+			    don't get filename conversion.  The caller
+			    of unexec() is assumed to have done this
+			    already (it's easier to do it this way than
+			    to modify all the unexec modules to ensure
+			    that all weirdo functions, such as
+			    elf_write_modified_data(), have proper
+			    filename conversion applied). */
+#include <config.h>
+#define PERROR(file) report_error (file, new)
+#endif
+#if __STDC__ || defined(STDC_HEADERS)
+/* I don't know how correct this attempt to get more prototypes is... */
+# if defined(sun) && defined(_POSIX_SOURCE)
+#  undef _POSIX_SOURCE
+# endif
+# if defined(__lucid) && !defined(__STDC_EXTENDED__)
+#  define __STDC_EXTENDED__ 1
+# endif
+# include <stdlib.h>
+# include <unistd.h>
+# include <string.h>
+# ifdef __lucid
+#  include <sysent.h>
+# endif
+#endif
+/* I don't understand this, but it's necessary to get some slots in struct exec
+from /usr/include/sys/exec.h when running LCC in strict ANSI mode.  We don't
+need this in K&R mode...
+*/
+#if defined(__lucid) && defined(__sparc) && !defined(sun)
+# define sun 1
+#endif
+#ifndef CANNOT_DUMP  /* all rest of file!  */
+#ifdef COFF_ENCAPSULATE
+int need_coff_header = 1;
+#include <coff-encap/a.out.encap.h> /* The location might be a poor assumption */
+#else
+#ifdef MSDOS
+#if __DJGPP__ > 1
+#include <fcntl.h>  /* for O_RDONLY, O_RDWR */
+#endif
+#include <coff.h>
+#define filehdr external_filehdr
+#define scnhdr external_scnhdr
+#define syment external_syment
+#define auxent external_auxent
+#define n_numaux e_numaux
+#define n_type e_type
+struct aouthdr
+{
+unsigned short	magic;	/* type of file				*/
+unsigned short	vstamp;	/* version stamp			*/
+unsigned long		tsize;	/* text size in bytes, padded to FW bdry*/
+unsigned long		dsize;	/* initialized data "  "		*/
+unsigned long		bsize;	/* uninitialized data "   "		*/
+unsigned long		entry;	/* entry pt.				*/
+unsigned long	 	text_start;/* base of text used for this file */
+unsigned long	 	data_start;/* base of data used for this file */
+};
+#else /* not MSDOS */
+#include <a.out.h>
+#endif /* not MSDOS */
+#endif /* not COFF_ENCAPSULATE */
+/* Define getpagesize if the system does not.
+Note that this may depend on symbols defined in a.out.h.  */
+#include "getpagesize.h"
+#ifndef makedev			/* Try to detect types.h already loaded */
+#include <sys/types.h>
+#endif /* makedev */
+#include <stdio.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <sys/file.h>	/* Must be after sys/types.h for USG and BSD4_1*/
+#ifdef USG5
+#include <fcntl.h>
+#endif
+#ifndef O_RDONLY
+#define O_RDONLY 0
+#endif
+#ifndef O_RDWR
+#define O_RDWR 2
+#endif
+extern char *start_of_text ();		/* Start of text */
+extern void *start_of_data ();		/* Start of initialized data */
+#ifdef COFF
+static long block_copy_start;		/* Old executable start point */
+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 */
+#define SYMS_START block_copy_start
+static long text_scnptr;
+static long data_scnptr;
+#else /* not COFF */
+#ifdef __STDC__
+#ifndef __sys_stdtypes_h
+#ifndef _PTRDIFF_T
+typedef long ptrdiff_t;
+#endif
+#endif
+#ifndef HPUX
+/* not sure where this for NetBSD should really go
+and it probably applies to other systems */
+#if !defined(__NetBSD__) && !defined(__bsdi__)
+extern void *sbrk (ptrdiff_t);
+#else
+extern char *sbrk ();
+#endif /* __NetBSD__ */
+#endif /* HPUX */
+#else
+extern void *sbrk ();
+#endif
+#define SYMS_START ((long) N_SYMOFF (ohdr))
+/* Some machines override the structure name for an a.out header.  */
+#ifndef EXEC_HDR_TYPE
+#define EXEC_HDR_TYPE struct exec
+#endif
+#ifdef HPUX
+#ifdef HP9000S200_ID
+#define MY_ID HP9000S200_ID
+#else
+#include <model.h>
+#define MY_ID MYSYS
+#endif /* no HP9000S200_ID */
+static MAGIC OLDMAGIC = {MY_ID, SHARE_MAGIC};
+static MAGIC NEWMAGIC = {MY_ID, DEMAND_MAGIC};
+#define N_TXTOFF(x) TEXT_OFFSET(x)
+#define N_SYMOFF(x) LESYM_OFFSET(x)
+static EXEC_HDR_TYPE hdr, ohdr;
+#else /* not HPUX */
+#if defined (USG) && !defined (IBMAIX) && !defined (IRIS) && !defined (COFF_ENCAPSULATE) && !defined (LINUX)
+static struct bhdr hdr, ohdr;
+#define a_magic fmagic
+#define a_text tsize
+#define a_data dsize
+#define a_bss bsize
+#define a_syms ssize
+#define a_trsize rtsize
+#define a_drsize rdsize
+#define a_entry entry
+#define	N_BADMAG(x) \
+(((x).fmagic)!=OMAGIC && ((x).fmagic)!=NMAGIC &&\
+((x).fmagic)!=FMAGIC && ((x).fmagic)!=IMAGIC)
+#define NEWMAGIC FMAGIC
+#else /* IRIS or IBMAIX or not USG */
+static EXEC_HDR_TYPE hdr, ohdr;
+#define NEWMAGIC ZMAGIC
+#endif /* IRIS or IBMAIX not USG */
+#endif /* not HPUX */
+static int unexec_text_start;
+static int unexec_data_start;
+#ifdef COFF_ENCAPSULATE
+/* coffheader is defined in the GNU a.out.encap.h file.  */
+struct coffheader coffheader;
+#endif
+#endif /* not COFF */
+static int pagemask;
+/* 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 is a no-op on ordinary machines, but not on all.  */
+#ifndef ADDR_CORRECT   /* Let m-*.h files override this definition */
+#define ADDR_CORRECT(x) ((char *)(x) - (char*)0)
+#endif
+#ifdef emacs
+#include "lisp.h"
+static void
+report_error (file, fd)
+CONST char *file;
+int fd;
+{
+if (fd)
+close (fd);
+report_file_error ("Cannot unexec",
+		     Fcons (build_ext_string (file, FORMAT_FILENAME), Qnil));
+}
+#endif /* emacs */
+#define ERROR0(msg) report_error_1 (new, msg, 0, 0); return -1
+#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 void
+report_error_1 (fd, msg, a1, a2)
+int fd;
+CONST char *msg;
+int a1, a2;
+{
+close (fd);
+#ifdef emacs
+error (msg, a1, a2);
+#else
+fprintf (stderr, msg, a1, a2);
+fprintf (stderr, "\n");
+#endif
+}
+static int make_hdr (int new, int a_out, unsigned data_start,
+		     unsigned bss_start, unsigned entry_address,
+		     char *a_name, char *new_name);
+static int copy_text_and_data (int new, int a_out);
+static int copy_sym (int new, int a_out, char *a_name, char *new_name);
+static void mark_x (char *name);
+/* ****************************************************************
+* unexec
+*
+* driving logic.
+*/
+int
+unexec (new_name, a_name, data_start, bss_start, entry_address)
+char *new_name, *a_name;
+unsigned data_start, bss_start, entry_address;
+{
+int new, a_out = -1;
+if (a_name && (a_out = open (a_name, O_RDONLY)) < 0)
+{
+PERROR (a_name);
+}
+if ((new = creat (new_name, 0666)) < 0)
+{
+PERROR (new_name);
+}
+if (make_hdr (new, a_out, data_start, bss_start, entry_address, a_name, new_name) < 0
+|| copy_text_and_data (new, a_out) < 0
+|| copy_sym (new, a_out, a_name, new_name) < 0
+#ifdef COFF
+#ifndef COFF_BSD_SYMBOLS
+|| adjust_lnnoptrs (new, a_out, new_name) < 0
+#endif
+#endif
+)
+{
+close (new);
+/* unlink (new_name);	    	/ * Failed, unlink new a.out */
+return -1;
+}
+close (new);
+if (a_out >= 0)
+close (a_out);
+mark_x (new_name);
+return 0;
+}
+/* ****************************************************************
+* make_hdr
+*
+* Make the header in the new a.out from the header in core.
+* Modify the text and data sizes.
+*/
+static int
+make_hdr (int new, int a_out, unsigned data_start, unsigned bss_start,
+	  unsigned entry_address, char *a_name, char *new_name)
+{
+#ifdef COFF
+auto struct scnhdr f_thdr;		/* Text section header */
+auto struct scnhdr f_dhdr;		/* Data section header */
+auto struct scnhdr f_bhdr;		/* Bss section header */
+auto struct scnhdr scntemp;		/* Temporary section header */
+int scns;
+#endif /* COFF */
+#ifdef USG_SHARED_LIBRARIES
+extern unsigned int bss_end;
+#else
+unsigned int bss_end;
+#endif
+pagemask = getpagesize () - 1;
+/* Adjust text/data boundary. */
+#ifdef NO_REMAP
+data_start = (int) start_of_data ();
+#else /* not NO_REMAP */
+if (!data_start)
+data_start = (int) start_of_data ();
+#endif /* not 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;
+/* Adjust data/bss boundary. */
+if (bss_start != 0)
+{
+bss_start = (ADDR_CORRECT (bss_start) + pagemask);
+/* (Up) to page bdry. */
+bss_start &= ~ pagemask;
+if (bss_start > bss_end)
+	{
+	  ERROR1 ("unexec: Specified bss_start (%u) is past end of program",
+		  bss_start);
+	}
+}
+else
+bss_start = bss_end;
+if (data_start > bss_start)	/* Can't have negative data size. */
+{
+ERROR2 ("unexec: data_start (%u) can't be greater than bss_start (%u)",
+	      data_start, bss_start);
+}
+#ifdef COFF
+/* Salvage as much info from the existing file as possible */
+if (a_out >= 0)
+{
+if (read (a_out, &f_hdr, sizeof (f_hdr)) != sizeof (f_hdr))
+	{
+	  PERROR (a_name);
+	}
+block_copy_start += sizeof (f_hdr);
+if (f_hdr.f_opthdr > 0)
+	{
+	  if (read (a_out, &f_ohdr, sizeof (f_ohdr)) != sizeof (f_ohdr))
+	    {
+	      PERROR (a_name);
+	    }
+	  block_copy_start += sizeof (f_ohdr);
+	}
+/* Loop through section headers, copying them in */
+lseek (a_out, sizeof (f_hdr) + f_hdr.f_opthdr, 0);
+for (scns = f_hdr.f_nscns; scns > 0; scns--) {
+	if (read (a_out, &scntemp, sizeof (scntemp)) != sizeof (scntemp))
+	  {
+	    PERROR (a_name);
+	  }
+	if (scntemp.s_scnptr > 0L)
+	  {
+if (block_copy_start < scntemp.s_scnptr + scntemp.s_size)
+	      block_copy_start = scntemp.s_scnptr + scntemp.s_size;
+	  }
+	if (strcmp (scntemp.s_name, ".text") == 0)
+	  {
+	    f_thdr = scntemp;
+	  }
+	else if (strcmp (scntemp.s_name, ".data") == 0)
+	  {
+	    f_dhdr = scntemp;
+	  }
+	else if (strcmp (scntemp.s_name, ".bss") == 0)
+	  {
+	    f_bhdr = scntemp;
+	  }
+}
+}
+else
+{
+ERROR0 ("can't build a COFF file from scratch yet");
+}
+/* Now we alter the contents of all the f_*hdr variables
+to correspond to what we want to dump.  */
+#ifdef USG_SHARED_LIBRARIES
+/* The amount of data we're adding to the file is distance from the
+* end of the original .data space to the current end of the .data
+* space.
+*/
+bias = bss_start - (f_ohdr.data_start + f_dhdr.s_size);
+#endif
+f_hdr.f_flags |= (F_RELFLG | F_EXEC);
+#ifdef TPIX
+f_hdr.f_nscns = 3;
+#endif
+#ifdef EXEC_MAGIC
+f_ohdr.magic = EXEC_MAGIC;
+#endif
+#ifndef NO_REMAP
+f_ohdr.text_start = (long) start_of_text ();
+f_ohdr.tsize = data_start - f_ohdr.text_start;
+f_ohdr.data_start = data_start;
+#endif /* NO_REMAP */
+f_ohdr.dsize = bss_start - f_ohdr.data_start;
+f_ohdr.bsize = bss_end - bss_start;
+#ifndef KEEP_OLD_TEXT_SCNPTR
+/* On some machines, the old values are right.
+??? Maybe on all machines with NO_REMAP.  */
+f_thdr.s_size = f_ohdr.tsize;
+f_thdr.s_scnptr = sizeof (f_hdr) + sizeof (f_ohdr);
+f_thdr.s_scnptr += (f_hdr.f_nscns) * (sizeof (f_thdr));
+#endif /* KEEP_OLD_TEXT_SCNPTR */
+#ifdef ADJUST_TEXT_SCNHDR_SIZE
+/* On some machines, `text size' includes all headers.  */
+f_thdr.s_size -= f_thdr.s_scnptr;
+#endif /* ADJUST_TEST_SCNHDR_SIZE */
+lnnoptr = f_thdr.s_lnnoptr;
+#ifdef SECTION_ALIGNMENT
+/* Some systems require special alignment
+of the sections in the file itself.  */
+f_thdr.s_scnptr
+= (f_thdr.s_scnptr + SECTION_ALIGNMENT) & ~SECTION_ALIGNMENT;
+#endif /* SECTION_ALIGNMENT */
+#ifdef TPIX
+f_thdr.s_scnptr = 0xd0;
+#endif
+text_scnptr = f_thdr.s_scnptr;
+#ifdef ADJUST_TEXTBASE
+text_scnptr = sizeof (f_hdr) + sizeof (f_ohdr) + (f_hdr.f_nscns) * (sizeof (f_thdr));
+#endif
+#ifndef KEEP_OLD_PADDR
+f_dhdr.s_paddr = f_ohdr.data_start;
+#endif /* KEEP_OLD_PADDR */
+f_dhdr.s_vaddr = f_ohdr.data_start;
+f_dhdr.s_size = f_ohdr.dsize;
+f_dhdr.s_scnptr = f_thdr.s_scnptr + f_thdr.s_size;
+#ifdef SECTION_ALIGNMENT
+/* Some systems require special alignment
+of the sections in the file itself.  */
+f_dhdr.s_scnptr
+= (f_dhdr.s_scnptr + SECTION_ALIGNMENT) & ~SECTION_ALIGNMENT;
+#endif /* SECTION_ALIGNMENT */
+#ifdef DATA_SECTION_ALIGNMENT
+/* Some systems require special alignment
+of the data section only.  */
+f_dhdr.s_scnptr
+= (f_dhdr.s_scnptr + DATA_SECTION_ALIGNMENT) & ~DATA_SECTION_ALIGNMENT;
+#endif /* DATA_SECTION_ALIGNMENT */
+data_scnptr = f_dhdr.s_scnptr;
+#ifndef KEEP_OLD_PADDR
+f_bhdr.s_paddr = f_ohdr.data_start + f_ohdr.dsize;
+#endif /* KEEP_OLD_PADDR */
+f_bhdr.s_vaddr = f_ohdr.data_start + f_ohdr.dsize;
+f_bhdr.s_size = f_ohdr.bsize;
+f_bhdr.s_scnptr = 0L;
+#ifndef USG_SHARED_LIBRARIES
+bias = f_dhdr.s_scnptr + f_dhdr.s_size - block_copy_start;
+#endif
+if (f_hdr.f_symptr > 0L)
+{
+f_hdr.f_symptr += bias;
+}
+if (f_thdr.s_lnnoptr > 0L)
+{
+f_thdr.s_lnnoptr += bias;
+}
+#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);
+}
+if (write (new, &f_ohdr, sizeof (f_ohdr)) != sizeof (f_ohdr))
+{
+PERROR (new_name);
+}
+#ifndef USG_SHARED_LIBRARIES
+if (write (new, &f_thdr, sizeof (f_thdr)) != sizeof (f_thdr))
+{
+PERROR (new_name);
+}
+if (write (new, &f_dhdr, sizeof (f_dhdr)) != sizeof (f_dhdr))
+{
+PERROR (new_name);
+}
+if (write (new, &f_bhdr, sizeof (f_bhdr)) != sizeof (f_bhdr))
+{
+PERROR (new_name);
+}
+#else /* USG_SHARED_LIBRARIES */
+/* The purpose of this code is to write out the new file's section
+* header table.
+*
+* Scan through the original file's sections.  If the encountered
+* section is one we know (.text, .data or .bss), write out the
+* correct header.  If it is a section we do not know (such as
+* .lib), adjust the address of where the section data is in the
+* file, and write out the header.
+*
+* If any section precedes .text or .data in the file, this code
+* will not adjust the file pointer for that section correctly.
+*/
+/* This used to use sizeof (f_ohdr) instead of .f_opthdr.
+.f_opthdr is said to be right when there is no optional header.  */
+lseek (a_out, sizeof (f_hdr) + f_hdr.f_opthdr, 0);
+for (scns = f_hdr.f_nscns; scns > 0; scns--)
+{
+if (read (a_out, &scntemp, sizeof (scntemp)) != sizeof (scntemp))
+	PERROR (a_name);
+if (!strcmp (scntemp.s_name, f_thdr.s_name))	/* .text */
+	{
+	  if (write (new, &f_thdr, sizeof (f_thdr)) != sizeof (f_thdr))
+	    PERROR (new_name);
+	}
+else if (!strcmp (scntemp.s_name, f_dhdr.s_name))	/* .data */
+	{
+	  if (write (new, &f_dhdr, sizeof (f_dhdr)) != sizeof (f_dhdr))
+	    PERROR (new_name);
+	}
+else if (!strcmp (scntemp.s_name, f_bhdr.s_name))	/* .bss */
+	{
+	  if (write (new, &f_bhdr, sizeof (f_bhdr)) != sizeof (f_bhdr))
+	    PERROR (new_name);
+	}
+else
+	{
+	  if (scntemp.s_scnptr)
+	    scntemp.s_scnptr += bias;
+	  if (write (new, &scntemp, sizeof (scntemp)) != sizeof (scntemp))
+	    PERROR (new_name);
+	}
+}
+#endif /* USG_SHARED_LIBRARIES */
+return (0);
+#else /* if not COFF */
+/* Get symbol table info from header of a.out file if given one. */
+if (a_out >= 0)
+{
+#ifdef COFF_ENCAPSULATE
+if (read (a_out, &coffheader, sizeof coffheader) != sizeof coffheader)
+	{
+	  PERROR(a_name);
+	}
+if (coffheader.f_magic != COFF_MAGIC)
+	{
+	  ERROR1("%s doesn't have legal coff magic number\n", a_name);
+	}
+#endif
+if (read (a_out, (char *) &ohdr, sizeof hdr) != sizeof hdr)
+	{
+	  PERROR (a_name);
+	}
+if (N_BADMAG (ohdr))
+	{
+	  ERROR1 ("invalid magic number in %s", a_name);
+	}
+hdr = ohdr;
+}
+else
+{
+#ifdef COFF_ENCAPSULATE
+/* We probably could without too much trouble. The code is in gld
+* but I don't have that much time or incentive.
+*/
+ERROR0 ("can't build a COFF file from scratch yet");
+#else
+memset ((void *)&hdr, 0, sizeof hdr);
+#endif
+}
+unexec_text_start = (long) start_of_text ();
+unexec_data_start = data_start;
+/* Machine-dependent fixup for header, or maybe for unexec_text_start */
+#ifdef ADJUST_EXEC_HEADER
+ADJUST_EXEC_HEADER;
+#endif /* ADJUST_EXEC_HEADER */
+hdr.a_trsize = 0;
+hdr.a_drsize = 0;
+if (entry_address != 0)
+hdr.a_entry = entry_address;
+hdr.a_bss = bss_end - bss_start;
+hdr.a_data = bss_start - data_start;
+#ifdef NO_REMAP
+hdr.a_text = ohdr.a_text;
+#else /* not NO_REMAP */
+hdr.a_text = data_start - unexec_text_start;
+#ifdef A_TEXT_OFFSET
+hdr.a_text += A_TEXT_OFFSET (ohdr);
+#endif
+#endif /* not NO_REMAP */
+#ifdef COFF_ENCAPSULATE
+/* We are encapsulating BSD format within COFF format.  */
+{
+struct coffscn *tp, *dp, *bp;
+tp = &coffheader.scns[0];
+dp = &coffheader.scns[1];
+bp = &coffheader.scns[2];
+tp->s_size = hdr.a_text + sizeof(struct exec);
+dp->s_paddr = data_start;
+dp->s_vaddr = data_start;
+dp->s_size = hdr.a_data;
+bp->s_paddr = dp->s_vaddr + dp->s_size;
+bp->s_vaddr = bp->s_paddr;
+bp->s_size = hdr.a_bss;
+coffheader.tsize = tp->s_size;
+coffheader.dsize = dp->s_size;
+coffheader.bsize = bp->s_size;
+coffheader.text_start = tp->s_vaddr;
+coffheader.data_start = dp->s_vaddr;
+}
+if (write (new, &coffheader, sizeof coffheader) != sizeof coffheader)
+{
+PERROR(new_name);
+}
+#endif /* COFF_ENCAPSULATE */
+if (write (new, (char *) &hdr, sizeof hdr) != sizeof hdr)
+{
+PERROR (new_name);
+}
+#if 0 /* This #ifndef caused a bug on Linux when using QMAGIC.  */
+/* This adjustment was done above only #ifndef NO_REMAP,
+so only undo it now #ifndef NO_REMAP.  */
+/* #ifndef NO_REMAP  */
+#endif
+#ifdef A_TEXT_OFFSET
+hdr.a_text -= A_TEXT_OFFSET (ohdr);
+#endif
+return 0;
+#endif /* not COFF */
+}
+static void write_segment (int, char *, char *);
+/* ****************************************************************
+* copy_text_and_data
+*
+* Copy the text and data segments from memory to the new a.out
+*/
+static int
+copy_text_and_data (int new, int a_out)
+{
+char *end;
+char *ptr;
+#ifdef COFF
+#ifdef USG_SHARED_LIBRARIES
+int scns;
+struct scnhdr scntemp;		/* Temporary section header */
+/* The purpose of this code is to write out the new file's section
+* contents.
+*
+* Step through the section table.  If we know the section (.text,
+* .data) do the appropriate thing.  Otherwise, if the section has
+* no allocated space in the file (.bss), do nothing.  Otherwise,
+* the section has space allocated in the file, and is not a section
+* we know.  So just copy it.
+*/
+lseek (a_out, sizeof (struct filehdr) + sizeof (struct aouthdr), 0);
+for (scns = f_hdr.f_nscns; scns > 0; scns--)
+{
+if (read (a_out, &scntemp, sizeof (scntemp)) != sizeof (scntemp))
+	PERROR ("temacs");
+if (!strcmp (scntemp.s_name, ".text"))
+	{
+	  lseek (new, (long) text_scnptr, 0);
+	  ptr = (char *) f_ohdr.text_start;
+	  end = ptr + f_ohdr.tsize;
+	  write_segment (new, ptr, end);
+	}
+else if (!strcmp (scntemp.s_name, ".data"))
+	{
+	  lseek (new, (long) data_scnptr, 0);
+	  ptr = (char *) f_ohdr.data_start;
+	  end = ptr + f_ohdr.dsize;
+	  write_segment (new, ptr, end);
+	}
+else if (!scntemp.s_scnptr)
+	; /* do nothing - no data for this section */
+else
+	{
+	  char page[BUFSIZ];
+	  int size, n;
+	  long old_a_out_ptr = lseek (a_out, 0, 1);
+	  lseek (a_out, scntemp.s_scnptr, 0);
+	  for (size = scntemp.s_size; size > 0; size -= sizeof (page))
+	    {
+	      n = size > sizeof (page) ? sizeof (page) : size;
+	      if (read (a_out, page, n) != n || write (new, page, n) != n)
+		PERROR ("emacs");
+	    }
+	  lseek (a_out, old_a_out_ptr, 0);
+	}
+}
+#else /* COFF, but not USG_SHARED_LIBRARIES */
+#ifdef MSDOS
+#if __DJGPP__ >= 2
+/* Dump the original table of exception handlers, not the one
+where our exception hooks are registered.  */
+__djgpp_exception_toggle ();
+#endif
+#endif
+lseek (new, (long) text_scnptr, 0);
+ptr = (char *) f_ohdr.text_start;
+#ifdef HEADER_INCL_IN_TEXT
+/* For Gould UTX/32, text starts after headers */
+ptr = (char *) (ptr + text_scnptr);
+#endif /* HEADER_INCL_IN_TEXT */
+end = ptr + f_ohdr.tsize;
+write_segment (new, ptr, end);
+lseek (new, (long) data_scnptr, 0);
+ptr = (char *) f_ohdr.data_start;
+end = ptr + f_ohdr.dsize;
+write_segment (new, ptr, end);
+#ifdef MSDOS
+#if __DJGPP__ >= 2
+/* Restore our exception hooks.  */
+__djgpp_exception_toggle ();
+#endif
+#endif
+#endif /* USG_SHARED_LIBRARIES */
+#else /* if not COFF */
+/* Some machines count the header as part of the text segment.
+That is to say, the header appears in core
+just before the address that start_of_text returns.
+For them, N_TXTOFF is the place where the header goes.
+We must adjust the seek to the place after the header.
+Note that at this point hdr.a_text does *not* count
+the extra A_TEXT_OFFSET bytes, only the actual bytes of code.  */
+#ifdef A_TEXT_SEEK
+lseek (new, (long) A_TEXT_SEEK (hdr), 0);
+#else
+lseek (new, (long) N_TXTOFF (hdr), 0);
+#endif /* no A_TEXT_SEEK */
+#ifdef RISCiX
+/* Acorn's RISC-iX has a wacky way of initialising the position of the heap.
+* There is a little table in crt0.o that is filled at link time with
+* the min and current brk positions, among other things.  When start
+* runs, it copies the table to where these parameters live during
+* execution.  This data is in text space, so it cannot be modified here
+* before saving the executable, so the data is written manually.  In
+* addition, the table does not have a label, and the nearest accessible
+* label (mcount) is not prefixed with a '_', thus making it inaccessible
+* from within C programs.  To overcome this, emacs's executable is passed
+* through the command 'nm %s | fgrep mcount' into a pipe, and the
+* resultant output is then used to find the address of 'mcount'.  As far as
+* is possible to determine, in RISC-iX releases prior to 1.2, the negative
+* offset of the table from mcount is 0x2c, whereas from 1.2 onwards it is
+* 0x30.  bss_end has been rounded up to page boundary.  This solution is
+* based on suggestions made by Kevin Welton and Steve Hunt of Acorn, and
+* avoids the need for a custom version of crt0.o for emacs which has its
+* table in data space.
+*/
+{
+char command[1024];
+char errbuf[1024];
+char address_text[32];
+int  proforma[4];
+FILE *pfile;
+char *temp_ptr;
+char c;
+int mcount_address, mcount_offset, count;
+extern char *_execname;
+/* The use of _execname is incompatible with RISCiX 1.1 */
+sprintf (command, "nm %s | fgrep mcount", _execname);
+if ( (pfile = popen(command, "r")) == NULL)
+{
+sprintf (errbuf, "Could not open pipe");
+PERROR (errbuf);
+}
+count=0;
+while ( ((c=getc(pfile)) != EOF) && (c != ' ') && (count < 31))
+address_text[count++]=c;
+address_text[count]=0;
+if ((count == 0) || pclose(pfile) != NULL)
+{
+sprintf (errbuf, "Failed to execute the command '%s'\n", command);
+PERROR (errbuf);
+}
+sscanf(address_text, "%x", &mcount_address);
+ptr = (char *) unexec_text_start;
+mcount_offset = (char *)mcount_address - ptr;
+#ifdef RISCiX_1_1
+#define EDATA_OFFSET 0x2c
+#else
+#define EDATA_OFFSET 0x30
+#endif
+end = ptr + mcount_offset - EDATA_OFFSET;
+write_segment (new, ptr, end);
+proforma[0] = bss_end;	/* becomes _edata */
+proforma[1] = bss_end;	/* becomes _end */
+proforma[2] = bss_end;	/* becomes _minbrk */
+proforma[3] = bss_end;	/* becomes _curbrk */
+write (new, proforma, 16);
+temp_ptr = ptr;
+ptr = end + 16;
+end = temp_ptr + hdr.a_text;
+write_segment (new, ptr, end);
+}
+#else /* !RISCiX */
+ptr = (char *) unexec_text_start;
+end = ptr + hdr.a_text;
+write_segment (new, ptr, end);
+#endif /* RISCiX */
+ptr = (char *) unexec_data_start;
+end = ptr + hdr.a_data;
+/*  This lseek is certainly incorrect when A_TEXT_OFFSET
+and I believe it is a no-op otherwise.
+Let's see if its absence ever fails.  */
+/*  lseek (new, (long) N_TXTOFF (hdr) + hdr.a_text, 0); */
+write_segment (new, ptr, end);
+#endif /* not COFF */
+return 0;
+}
+static void
+write_segment (new, ptr, end)
+int new;
+char *ptr, *end;
+{
+int i, nwrite, ret;
+#if 0
+char buf[80];
+#endif
+extern int errno;
+/* This is the normal amount to write at once.
+It is the size of block that NFS uses.  */
+int writesize = 1 << 13;
+int pagesize = getpagesize ();
+char zeros[1 << 13];
+memset (zeros, 0, sizeof (zeros));
+for (i = 0; ptr < end;)
+{
+/* Distance to next multiple of writesize.  */
+nwrite = (((int) ptr + writesize) & -writesize) - (int) ptr;
+/* But not beyond specified end.  */
+if (nwrite > end - ptr) nwrite = end - ptr;
+ret = write (new, ptr, nwrite);
+/* If write gets a page fault, it means we reached
+	 a gap between the old text segment and the old data segment.
+	 This gap has probably been remapped into part of the text segment.
+	 So write zeros for it.  */
+if (ret == -1
+#ifdef EFAULT
+	  && errno == EFAULT
+#endif
+	  )
+	{
+	  /* Write only a page of zeros at once,
+	     so that we we don't overshoot the start
+	     of the valid memory in the old data segment.  */
+	  if (nwrite > pagesize)
+	    nwrite = pagesize;
+	  write (new, zeros, nwrite);
+	}
+#if 0 /* Now that we have can ask `write' to write more than a page,
+	 it is legit for write do less than the whole amount specified.  */
+else if (nwrite != ret)
+	{
+	  sprintf (buf,
+		   "unexec write failure: addr 0x%lx, fileno %d, size 0x%x, wrote 0x%x, errno %d",
+		   (unsigned long) ptr, new, nwrite, ret, errno);
+	  PERROR (buf);
+	}
+#endif
+i += nwrite;
+ptr += nwrite;
+}
+}
+/* ****************************************************************
+* copy_sym
+*
+* Copy the relocation information and symbol table from the a.out to the new
+*/
+static int
+copy_sym (int new, int a_out, char *a_name, char *new_name)
+{
+char page[1024];
+int n;
+if (a_out < 0)
+return 0;
+#ifdef COFF
+if (SYMS_START == 0L)
+return 0;
+#endif  /* COFF */
+#ifdef COFF
+if (lnnoptr)			/* if there is line number info */
+lseek (a_out, lnnoptr, 0);	/* start copying from there */
+else
+#endif /* COFF */
+lseek (a_out, SYMS_START, 0);	/* Position a.out to symtab. */
+while ((n = read (a_out, page, sizeof page)) > 0)
+{
+if (write (new, page, n) != n)
+	{
+	  PERROR (new_name);
+	}
+}
+if (n < 0)
+{
+PERROR (a_name);
+}
+return 0;
+}
+/* ****************************************************************
+* mark_x
+*
+* After successfully building the new a.out, mark it executable
+*/
+static void
+mark_x (char *name)
+{
+struct stat sbuf;
+int um;
+int new = 0;  /* for PERROR */
+um = umask (777);
+umask (um);
+if (stat (name, &sbuf) == -1)
+{
+PERROR (name);
+}
+sbuf.st_mode |= 0111 & ~um;
+if (chmod (name, sbuf.st_mode) == -1)
+PERROR (name);
+}
+#ifdef COFF
+#ifndef COFF_BSD_SYMBOLS
+/*
+*	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.
+*/
+/* 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.  */
+int
+adjust_lnnoptrs (writedesc, readdesc, new_name)
+int writedesc;
+int readdesc;
+char *new_name;
+{
+int nsyms;
+int new;
+#if defined (amdahl_uts) || defined (pfa)
+SYMENT symentry;
+AUXENT auxentry;
+#else
+struct syment symentry;
+union auxent auxentry;
+#endif
+if (!lnnoptr || !f_hdr.f_symptr)
+return 0;
+#ifdef MSDOS
+if ((new = writedesc) < 0)
+#else
+if ((new = open (new_name, O_RDWR)) < 0)
+#endif
+{
+PERROR (new_name);
+return -1;
+}
+lseek (new, f_hdr.f_symptr, 0);
+for (nsyms = 0; nsyms < f_hdr.f_nsyms; nsyms++)
+{
+read (new, &symentry, SYMESZ);
+if (symentry.n_numaux)
+	{
+	  read (new, &auxentry, AUXESZ);
+	  nsyms++;
+	  if (ISFCN (symentry.n_type) || symentry.n_type == 0x2400)
+	    {
+	      auxentry.x_sym.x_fcnary.x_fcn.x_lnnoptr += bias;
+	      lseek (new, -AUXESZ, 1);
+	      write (new, &auxentry, AUXESZ);
+	    }
+	}
+}
+#ifndef MSDOS
+close (new);
+#endif
+return 0;
+}
+#endif /* COFF_BSD_SYMBOLS */
+#endif /* COFF */
+#endif /* not CANNOT_DUMP */

Mercurial > hg > xemacs-beta

comparison src/unexec.c @ 0:376386a54a3c r19-14