xemacs-beta: src/unexconvex.c comparison

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

Import from CVS: tag r19-14

author	cvs
date	Mon, 13 Aug 2007 08:45:50 +0200
parents
children	c42ec1d1cded

comparison

equal deleted inserted replaced

--1:000000000000
+:376386a54a3c
+/* Modified version of unexec for convex machines.
+Copyright (C) 1985, 1986, 1988 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. */
+/* modified for C-1 arch by jthomp@convex 871103 */
+/* Corrected to support convex SOFF object file formats and thread specific
+* regions.  streepy@convex 890302
+*/
+/*
+* 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
+*
+*/
+/* 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.
+*/
+#include <config.h>
+#define PERROR(file) report_error (file, new)
+#include <a.out.h>
+/* Define getpagesize () if the system does not.
+Note that this may depend on symbols defined in a.out.h
+*/
+#include "getpagesize.h"
+#include <sys/types.h>
+#include <stdio.h>
+#include <sys/stat.h>
+#include <errno.h>
+extern char *start_of_text ();		/* Start of text */
+extern char *start_of_data ();		/* Start of initialized data */
+#include <machine/filehdr.h>
+#include <machine/opthdr.h>
+#include <machine/scnhdr.h>
+#include <machine/pte.h>
+static long block_copy_start;	/* Old executable start point */
+static struct filehdr f_hdr;	/* File header */
+static struct opthdr f_ohdr;	/* Optional file header (a.out) */
+long bias;			/* Bias to add for growth */
+#define SYMS_START block_copy_start
+static long text_scnptr;
+static long data_scnptr;
+static int pagemask;
+static int pagesz;
+static
+report_error (file, fd)
+char *file;
+int fd;
+{
+if (fd)
+	close (fd);
+error ("Failure operating on %s", file);
+}
+#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
+report_error_1 (fd, msg, a1, a2)
+int fd;
+char *msg;
+int a1, a2;
+{
+close (fd);
+error (msg, a1, a2);
+}
+/* ****************************************************************
+* 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 new, a_out = -1;
+if (a_name && (a_out = open (a_name, 0)) < 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) < 0
+|| copy_sym (new, a_out, a_name, new_name) < 0 ) {
+	close (new);
+	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.
+*/
+struct scnhdr *stbl;		/* Table of all scnhdr's */
+struct scnhdr *f_thdr;		/* Text section header */
+struct scnhdr *f_dhdr;		/* Data section header */
+struct scnhdr *f_tdhdr;	/* Thread Data section header */
+struct scnhdr *f_bhdr;		/* Bss section header */
+struct scnhdr *f_tbhdr;	/* Thread Bss section header */
+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;
+{
+int scns;
+unsigned int bss_end;
+unsigned int eo_data;	/* End of initialized data in new exec file */
+int scntype;		/* Section type */
+int i;			/* Var for sorting by vaddr */
+struct scnhdr scntemp;	/* For swapping entries in sort */
+extern char *start_of_data();
+pagemask = (pagesz = getpagesize()) - 1;
+/* Adjust text/data boundary. */
+if (!data_start)
+	data_start = (unsigned) start_of_data ();
+data_start = data_start & ~pagemask; /* (Down) to page boundary. */
+bss_end = (sbrk(0) + pagemask) & ~pagemask;
+/* Adjust data/bss boundary. */
+if (bss_start != 0) {
+	bss_start = (bss_start + pagemask) & ~pagemask;/* (Up) to page bdry. */
+	if (bss_start > bss_end) {
+	    ERROR1 ("unexec: Specified bss_start (%x) 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 (%x) can't be greater than bss_start (%x)",
+		data_start, bss_start);
+}
+/* Salvage as much info from the existing file as possible */
+if (a_out < 0) {
+	ERROR0 ("can't build a COFF file from scratch yet");
+	/*NOTREACHED*/
+}
+if (read (a_out, &f_hdr, sizeof (f_hdr)) != sizeof (f_hdr)) {
+	PERROR (a_name);
+}
+block_copy_start += sizeof (f_hdr);
+if (f_hdr.h_opthdr > 0) {
+	if (read (a_out, &f_ohdr, sizeof (f_ohdr)) != sizeof (f_ohdr)) {
+	    PERROR (a_name);
+	}
+	block_copy_start += sizeof (f_ohdr);
+}
+/* Allocate room for scn headers */
+stbl = (struct scnhdr *)malloc( sizeof(struct scnhdr) * f_hdr.h_nscns );
+if( stbl == NULL ) {
+	ERROR0( "unexec: malloc of stbl failed" );
+}
+f_tdhdr = f_tbhdr = NULL;
+/* Loop through section headers, copying them in */
+for (scns = 0; scns < f_hdr.h_nscns; scns++) {
+	if( read( a_out, &stbl[scns], sizeof(*stbl)) != sizeof(*stbl)) {
+	    PERROR (a_name);
+	}
+	scntype = stbl[scns].s_flags & S_TYPMASK; /* What type of section */
+	if( stbl[scns].s_scnptr > 0L) {
+	    if( block_copy_start < stbl[scns].s_scnptr + stbl[scns].s_size )
+		block_copy_start = stbl[scns].s_scnptr + stbl[scns].s_size;
+	}
+	if( scntype == S_TEXT) {
+	    f_thdr = &stbl[scns];
+	} else if( scntype == S_DATA) {
+	    f_dhdr = &stbl[scns];
+#ifdef S_TDATA
+	} else if( scntype == S_TDATA ) {
+	    f_tdhdr = &stbl[scns];
+	} else if( scntype == S_TBSS ) {
+	    f_tbhdr = &stbl[scns];
+#endif /* S_TDATA (thread stuff) */
+	} else if( scntype == S_BSS) {
+	    f_bhdr = &stbl[scns];
+	}
+}
+/* We will now convert TEXT and DATA into TEXT, BSS into DATA, and leave
+* all thread stuff alone.
+*/
+/* Now we alter the contents of all the f_*hdr variables
+to correspond to what we want to dump.  */
+f_thdr->s_vaddr = (long) start_of_text ();
+f_thdr->s_size = data_start - f_thdr->s_vaddr;
+f_thdr->s_scnptr = pagesz;
+f_thdr->s_relptr = 0;
+f_thdr->s_nrel = 0;
+eo_data = f_thdr->s_scnptr + f_thdr->s_size;
+if( f_tdhdr ) {		/* Process thread data */
+	f_tdhdr->s_vaddr = data_start;
+	f_tdhdr->s_size += f_dhdr->s_size - (data_start - f_dhdr->s_vaddr);
+	f_tdhdr->s_scnptr = eo_data;
+	f_tdhdr->s_relptr = 0;
+	f_tdhdr->s_nrel = 0;
+	eo_data += f_tdhdr->s_size;
+	/* And now for DATA */
+	f_dhdr->s_vaddr = f_bhdr->s_vaddr; /* Take BSS start address */
+	f_dhdr->s_size = bss_end - f_bhdr->s_vaddr;
+	f_dhdr->s_scnptr = eo_data;
+	f_dhdr->s_relptr = 0;
+	f_dhdr->s_nrel = 0;
+	eo_data += f_dhdr->s_size;
+} else {
+	f_dhdr->s_vaddr = data_start;
+	f_dhdr->s_size = bss_start - data_start;
+	f_dhdr->s_scnptr = eo_data;
+	f_dhdr->s_relptr = 0;
+	f_dhdr->s_nrel = 0;
+	eo_data += f_dhdr->s_size;
+}
+f_bhdr->s_vaddr = bss_start;
+f_bhdr->s_size = bss_end - bss_start + pagesz /* fudge */;
+f_bhdr->s_scnptr = 0;
+f_bhdr->s_relptr = 0;
+f_bhdr->s_nrel = 0;
+text_scnptr = f_thdr->s_scnptr;
+data_scnptr = f_dhdr->s_scnptr;
+bias = eo_data - block_copy_start;
+if (f_ohdr.o_symptr > 0L) {
+	f_ohdr.o_symptr += bias;
+}
+if (f_hdr.h_strptr > 0) {
+	f_hdr.h_strptr += bias;
+}
+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);
+}
+for( scns = 0; scns < f_hdr.h_nscns; scns++ ) {
+	/* This is a cheesy little loop to write out the section headers
+	 * in order of increasing virtual address. Dull but effective.
+	 */
+	for( i = scns+1; i < f_hdr.h_nscns; i++ ) {
+	    if( stbl[i].s_vaddr < stbl[scns].s_vaddr ) { /* Swap */
+		scntemp = stbl[i];
+		stbl[i] = stbl[scns];
+		stbl[scns] = scntemp;
+	    }
+	}
+}
+for( scns = 0; scns < f_hdr.h_nscns; scns++ ) {
+	if( write( new, &stbl[scns], sizeof(*stbl)) != sizeof(*stbl)) {
+	    PERROR (new_name);
+	}
+}
+return (0);
+}
+/* ****************************************************************
+* copy_text_and_data
+*
+* Copy the text and data segments from memory to the new a.out
+*/
+static int
+copy_text_and_data (new)
+int new;
+{
+int scns;
+for( scns = 0; scns < f_hdr.h_nscns; scns++ )
+	write_segment( new, &stbl[scns] );
+return 0;
+}
+write_segment( new, sptr )
+int new;
+struct scnhdr *sptr;
+{
+char *ptr, *end;
+int nwrite, ret;
+char buf[80];
+extern int errno;
+char zeros[128];
+if( sptr->s_scnptr == 0 )
+	return;			/* Nothing to do */
+if( lseek( new, (long) sptr->s_scnptr, 0 ) == -1 )
+	PERROR( "unexecing" );
+bzero (zeros, sizeof zeros);
+ptr = (char *) sptr->s_vaddr;
+end = ptr + sptr->s_size;
+while( ptr < end ) {
+	/* distance to next multiple of 128.  */
+	nwrite = (((int) ptr + 128) & -128) - (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 && errno == EFAULT)
+	    write (new, zeros, nwrite);
+	else if (nwrite != ret) {
+	    sprintf (buf,
+		     "unexec write failure: addr 0x%x, fileno %d, size 0x%x, wrote 0x%x, errno %d",
+		     ptr, new, nwrite, ret, errno);
+	    PERROR (buf);
+	}
+	ptr += nwrite;
+}
+}
+/* ****************************************************************
+* copy_sym
+*
+* 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;
+{
+char page[1024];
+int n;
+if (a_out < 0)
+	return 0;
+if (SYMS_START == 0L)
+	return 0;
+lseek (a_out, SYMS_START, 0);	/* Position a.out to symtab. */
+lseek( new, (long)f_ohdr.o_symptr, 0 );
+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
+mark_x (name)
+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);
+}
+/* Find the first pty letter.  This is usually 'p', as in ptyp0, but
+is sometimes configured down to 'm', 'n', or 'o' for some reason. */
+first_pty_letter ()
+{
+struct stat buf;
+char pty_name[16];
+char c;
+for (c = 'o'; c >= 'a'; c--)
+{
+sprintf (pty_name, "/dev/pty%c0", c);
+if (stat (pty_name, &buf) < 0)
+	return c + 1;
+}
+return 'a';
+}

Mercurial > hg > xemacs-beta

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