This is bsd_rsym.c in view mode; [Download] [Up]
/* Use this to build an executable rsym,
which will grab only the external symbols from an object file,
and put them in a simple format: (cf ext_sym.h)
This information will be used for relocation.
to compile use cc -g rsym.c -o rsym -I../h
*/
#define BSD
#include <stdio.h>
#include <a.out.h>
#include "ext_sym.h"
/* our defs */
#define TABLE_SIZE 3
#ifdef DEBUG
int debug =1;
#define dprintf(s,ar) if(debug) { printf(" ( s )",ar) ; fflush(stdout);}
#else
int debug =0;
#define dprintf(s,ar)
#endif
struct exec my_header;
struct syment *my_symbol_table;
char *my_string_table;
char *start_address;
/* this program will get the external symbols from a file writing
them out to a file together with their addresses */
void get_myself();
main(argc,argv)
int argc ;
char *argv[];
{
if (argc!=3) {perror("bad arg count");fflush(stdout);exit(1);}
get_myself(argv[1]);
output_externals(argv[2]);
}
void
get_myself(filename)
char *filename;
{
int i;
LDFILE *ldptr;
extern char *malloc();
ldptr = ldopen(filename, RDONLY);
if (ldptr == NULL) {
fprintf(stderr, "Can't open %s\n", filename);
exit(1);
}
ftell(ldptr);
fread(&my_header,sizeof(struct exec),1,ldptr);
if(N_BADMAG(my_header)){fprintf(stderr,"Bad magic %s",filename);
exit(1);};
if(fseek(ldptr,(int)N_SYMOFF(my_header),0))
{fprintf(stderr,"seek error");
exit(1);}
my_symbol_table
= (struct syment *)malloc(sizeof(struct syment) * NSYMS(my_header));
/*
sizeof(struct syment) and SYMESZ are not always the same.
*/
for (i = 0; i < NSYMS(my_header); i++)
FREAD(&my_symbol_table[i], SYMESZ, 1, ldptr);
/*
If the string table is not empty,
its length is stored after the symbol table,
This is not described in the manual, and may change in the future.
*/
/* fseek(ldptr,N_STROFF(my_header),0);
strings follow symbol table! */
if (FREAD(&i, 4, 1, ldptr) > 0) {
my_string_table = malloc(i);
if(debug)
{printf(" i is %d Fseek %d ",i,FSEEK(ldptr,i-1,1));
printf(" Fseek back %d ",FSEEK(ldptr,1-i,1));};
FSEEK(ldptr, -4, 1);
if(i!=(FREAD(my_string_table, 1, i, ldptr)))
{dprintf( i was %d ,i);
perror("rsym could not read bad string table") ;
exit(1);}
}
else {fprintf(stderr,"Error: There is no string table \n");
exit(1);}
ldclose(ldptr);
}
int
output_externals(outfile)
char *outfile;
{FILE *symout;
char *name;
struct lsymbol_table tab;
char out[4];
char tem[SYMNMLEN+1];
struct syment *p, *end;
tem[SYMNMLEN]=0;
tab.n_symbols=0;tab.tot_leng=0;
symout=fopen(outfile,"w");
if (!symout)
{perror(outfile); exit(1);};
fseek(symout,sizeof(struct lsymbol_table),0);
end = my_symbol_table + NSYMS(my_header);
for (p = my_symbol_table; p < end; p++) {
/*
Is the following check enough?
*/
if EXT_and_TEXT_BSS_DAT(p)
{ name= SYM_NAME(p);
{int i=0;
dprintf(tab.n_symbols %d , tab.n_symbols);
tab.n_symbols++;
fwrite(&(p->n_value),sizeof(int),1,symout);
dprintf( p->n_value %d , p->n_value);
dprintf( name %s , name);
while(tab.tot_leng++,*name)
putc(*name++,symout);
putc(0,symout);
/* fprintf(symout,name);
fprintf(symout," %d ", p->n_value);
*/
};
dprintf( NUM_AUX(p) %d , NUM_AUX(p));
dprintf( index , (int) (p - my_symbol_table) / sizeof(struct syment));
p = p + NUM_AUX(p); }
}
fseek(symout,0,0);
fwrite(&tab,sizeof(tab),1,symout);
fclose(symout);
return 0;
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.