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/* Waiting for papers! */
/*
* Do an unexec() for coff encapsulation. Uses the approach I took
* for AKCL, so don't be surprised if it doesn't look too much like
* the other unexec() routines. Assumes NO_REMAP. Should be easy to
* adapt to the emacs style unexec() if that is desired, but this works
* just fine for me with GCC/GAS/GLD under System V. - Jordan
*/
#include <sys/types.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <stdio.h>
#include "/usr/gnu/lib/gcc/gcc-include/a.out.h"
filecpy(to, from, n)
FILE *to, *from;
register int n;
{
char buffer[BUFSIZ];
for (;;)
if (n > BUFSIZ) {
fread(buffer, BUFSIZ, 1, from);
fwrite(buffer, BUFSIZ, 1, to);
n -= BUFSIZ;
} else if (n > 0) {
fread(buffer, 1, n, from);
fwrite(buffer, 1, n, to);
break;
} else
break;
}
/* ****************************************************************
* 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;
{
struct coffheader header1;
struct coffscn *tp, *dp, *bp;
struct exec header;
int stsize;
char *original_file = a_name;
char *save_file = new_name;
char *data_begin, *data_end;
int original_data;
FILE *original, *save;
register int n;
register char *p;
extern char *sbrk();
char stdin_buf[BUFSIZ], stdout_buf[BUFSIZ];
fclose(stdin);
original = fopen(original_file, "r");
if (stdin != original || original->_file != 0) {
fprintf(stderr, "unexec: Can't open the original file.\n");
exit(1);
}
setbuf(original, stdin_buf);
fclose(stdout);
unlink(save_file);
n = open(save_file, O_CREAT|O_WRONLY, 0777);
if (n != 1 || (save = fdopen(n, "w")) != stdout) {
fprintf(stderr, "unexec: Can't open the save file.\n");
exit(1);
}
setbuf(save, stdout_buf);
fread(&header1, sizeof(header1), 1, original);
tp = &header1.scns[0];
dp = &header1.scns[1];
bp = &header1.scns[2];
fread(&header, sizeof(header), 1, original);
data_begin=(char *)N_DATADDR(header);
data_end = sbrk(0);
original_data = header.a_data;
header.a_data = data_end - data_begin;
header.a_bss = 0;
dp->s_size = header.a_data;
bp->s_paddr = dp->s_vaddr + dp->s_size;
bp->s_vaddr = bp->s_paddr;
bp->s_size = 0;
header1.tsize = tp->s_size;
header1.dsize = dp->s_size;
header1.bsize = bp->s_size;
fwrite(&header1, sizeof(header1), 1, save);
fwrite(&header, sizeof(header), 1, save);
filecpy(save, original, header.a_text);
for (n = header.a_data, p = data_begin; ; n -= BUFSIZ, p += BUFSIZ)
if (n > BUFSIZ)
fwrite(p, BUFSIZ, 1, save);
else if (n > 0) {
fwrite(p, 1, n, save);
break;
} else
break;
fseek(original, original_data, 1);
filecpy(save, original, header.a_syms+header.a_trsize+header.a_drsize);
fread(&stsize, sizeof(stsize), 1, original);
fwrite(&stsize, sizeof(stsize), 1, save);
filecpy(save, original, stsize - sizeof(stsize));
fclose(original);
fclose(save);
}
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