freebsd-nq/usr.sbin/dbsym/dbsym.c
1993-06-12 14:49:13 +00:00

193 lines
3.8 KiB
C

/* Written by Pace Willisson (pace@blitz.com)
* and placed in the public domain.
*/
#include <stdio.h>
#include <a.out.h>
char *malloc ();
#define FILE_OFFSET(vadr) (((vadr) & ~0xff000000)-N_DATADDR(hdr)+N_DATOFF(hdr))
struct nlist *old_syms;
int num_old_syms;
char *old_strtab;
int old_strtab_size;
struct nlist *new_syms;
int num_new_syms;
int new_syms_bytes;
char *new_strtab;
int new_strtab_size;
int db_symtabsize_adr;
int db_symtab_adr;
int avail;
usage ()
{
fprintf (stderr, "usage: dbsym file\n");
exit (1);
}
struct exec hdr;
main (argc, argv)
char **argv;
{
FILE *f;
char *name;
extern int optind;
int c, i;
int need;
char *buf, *p;
struct nlist *nsp, *sp;
int len;
while ((c = getopt (argc, argv, "")) != EOF) {
switch (c) {
default:
usage ();
}
}
if (optind >= argc)
usage ();
name = argv[optind++];
if (optind != argc)
usage ();
if ((f = fopen (name, "r+")) == NULL) {
fprintf (stderr, "can't open %s\n", name);
exit (1);
}
if (fread ((char *)&hdr, sizeof hdr, 1, f) != 1) {
fprintf (stderr, "can't read header\n");
exit (1);
}
if (N_BADMAG (hdr)) {
fprintf (stderr, "bad magic number\n");
exit (1);
}
if (hdr.a_syms == 0) {
fprintf (stderr, "no symbols\n");
exit (1);
}
fseek (f, N_STROFF (hdr), 0);
if (fread ((char *)&old_strtab_size, sizeof (int), 1, f) != 1) {
fprintf (stderr, "can't read old strtab size\n");
exit (1);
}
if ((old_syms = (struct nlist *)malloc (hdr.a_syms)) == NULL
|| ((old_strtab = malloc (old_strtab_size)) == NULL)
|| ((new_syms = (struct nlist *)malloc (hdr.a_syms)) == NULL)
|| ((new_strtab = malloc (old_strtab_size)) == NULL)) {
fprintf (stderr, "out of memory\n");
exit (1);
}
fseek (f, N_SYMOFF (hdr), 0);
if (fread ((char *)old_syms, hdr.a_syms, 1, f) != 1) {
fprintf (stderr, "can't read symbols\n");
exit (1);
}
fseek (f, N_STROFF (hdr), 0);
if (fread ((char *)old_strtab, old_strtab_size, 1, f) != 1) {
fprintf (stderr, "can't read string table\n");
exit (1);
}
num_old_syms = hdr.a_syms / sizeof (struct nlist);
new_strtab_size = 4;
nsp = new_syms;
for (i = 0, sp = old_syms; i < num_old_syms; i++, sp++) {
if (sp->n_type & N_STAB)
continue;
if (sp->n_un.n_strx == 0)
continue;
if (sp->n_value < 0xfe000000)
continue;
if (sp->n_value >= 0xff000000)
continue;
name = old_strtab + sp->n_un.n_strx;
len = strlen (name);
if (len == 0)
continue;
if (len >= 2 && name[len - 2] == '.' && name[len - 1] == 'o')
continue;
if (strcmp (name, "gcc_compiled.") == 0)
continue;
*nsp = *sp;
nsp->n_un.n_strx = new_strtab_size;
strcpy (new_strtab + new_strtab_size, name);
new_strtab_size += len + 1;
nsp++;
if (strcmp (name, "_db_symtab") == 0)
db_symtab_adr = sp->n_value;
if (strcmp (name, "_db_symtabsize") == 0)
db_symtabsize_adr = sp->n_value;
}
if (db_symtab_adr == 0 || db_symtabsize_adr == 0) {
fprintf (stderr, "couldn't find db_symtab symbols\n");
exit (1);
}
*(int *)new_strtab = new_strtab_size;
num_new_syms = nsp - new_syms;
new_syms_bytes = num_new_syms * sizeof (struct nlist);
need = sizeof (int)
+ num_new_syms * sizeof (struct nlist)
+ new_strtab_size;
fseek (f, FILE_OFFSET (db_symtabsize_adr), 0);
if (fread ((char *)&avail, sizeof (int), 1, f) != 1) {
fprintf (stderr, "can't read symtabsize\n");
exit (1);
}
printf ("dbsym: need %d; avail %d\n", need, avail);
if (need > avail) {
fprintf (stderr, "not enough room in db_symtab array\n");
exit (1);
}
fseek (f, FILE_OFFSET (db_symtab_adr), 0);
fwrite ((char *)&new_syms_bytes, sizeof (int), 1, f);
fwrite ((char *)new_syms, new_syms_bytes, 1, f);
fwrite (new_strtab, new_strtab_size, 1, f);
fflush (f);
if (feof (f) || ferror (f)) {
fprintf (stderr, "write error\n");
exit (1);
}
exit (0);
}