github.com/dreamlayers.netbsd-mopd
1
0
Fork 0
mirror of https://github.com/dreamlayers/netbsd-mopd.git synced 2026-04-07 21:40:16 +00:00
Code Issues Projects Releases Wiki Activity

Clean up CheckAOutFileInfo & GetAOutFileInfo

Browse Source 
- Rework over complicated getMID with its double parameters and
  unnecessary assignments to a simple badMID, modelled on N_BADMAG
- Both CheckAOutFileInfo & GetAOutFileInfo now always rewind the
  fd before reading. They currently both leave the fd pointing
  directly after the in file exec struct header, but that matches
  the behaviour of similar methods
- Consistently handle swapped MID and AOUT magic values

We still have unnecessarily duplicated code here, but what is
here should be cleaner
This commit is contained in:
David Brownlee
2020-10-28 16:30:07 +00:00
committed by Boris Gjenero
parent 9238af826d
commit 2f79266747
1 changed files with 32 additions and 66 deletions
Download Patch File Download Diff File Expand all files Collapse all files

98
common/file.c
View File

@@ -34,6 +34,7 @@ __RCSID("$NetBSD: file.c,v 1.16 2016/06/08 01:11:49 christos Exp $");
#include "file.h"
#include "mopdef.h"
#include <stddef.h>
#include <stdbool.h>
#ifndef NOAOUT
# if defined(__NetBSD__) || defined(__OpenBSD__)
@@ -61,7 +62,7 @@ __RCSID("$NetBSD: file.c,v 1.16 2016/06/08 01:11:49 christos Exp $");
#ifndef NOAOUT
static int getCLBYTES(int);
static int getMID(int, int);
static bool badMID(int);
#endif
const char *
@@ -290,74 +291,59 @@ GetMopFileInfo(struct dllist *dl)
}
#ifndef NOAOUT
static int
getMID(int old_mid, int new_mid)
/* Returns true for unrecognised MID, else false */
static bool
badMID(int mid)
{
int mid;
mid = old_mid;
switch (new_mid) {
switch (mid) {
/* 0 is used by Athena 4.3BSD, Ultrix, and 4.3BSD-Quasijarus0c */
case 0:
mid = 0;
break;
case MID_I386:
mid = MID_I386;
break;
#ifdef MID_M68K
case MID_M68K:
mid = MID_M68K;
break;
#endif
#ifdef MID_M68K4K
case MID_M68K4K:
mid = MID_M68K4K;
break;
#endif
#ifdef MID_NS32532
case MID_NS32532:
mid = MID_NS32532;
break;
#endif
case MID_SPARC:
mid = MID_SPARC;
break;
#ifdef MID_PMAX
case MID_PMAX:
mid = MID_PMAX;
break;
#endif
#ifdef MID_VAX
case MID_VAX:
mid = MID_VAX;
break;
#endif
#ifdef MID_VAX1K
case MID_VAX1K:
mid = MID_VAX1K;
break;
#endif
#ifdef MID_ALPHA
case MID_ALPHA:
mid = MID_ALPHA;
break;
#endif
#ifdef MID_MIPS
case MID_MIPS:
mid = MID_MIPS;
break;
#endif
#ifdef MID_ARM6
case MID_ARM6:
mid = MID_ARM6;
break;
#endif
default:
break;
return true;
}
return(mid);
return false;
}
static int
@@ -638,34 +624,22 @@ CheckAOutFile(int fd)
return(-1);
#else
struct exec ex, ex_swap;
int mid = -1;
(void)lseek(fd, (off_t) 0, SEEK_SET);
if (read(fd, (char *)&ex, sizeof(ex)) != sizeof(ex))
return(-1);
return -1;
(void)lseek(fd, (off_t) 0, SEEK_SET);
if (read(fd, (char *)&ex_swap, sizeof(ex_swap)) != sizeof(ex_swap))
return(-1);
memcpy(&ex_swap, &ex, sizeof(ex));
mopFileSwapX((u_char *)&ex_swap, 0, 4);
(void)lseek(fd, (off_t) 0, SEEK_SET);
/* If mid == 0 is accepted, this is needed to avoid false positives. */
if (N_BADMAG (ex) && N_BADMAG (ex_swap)) {
return(-1);
}
if (N_BADMAG(ex) && N_BADMAG(ex_swap))
return -1;
mid = getMID(mid, N_GETMID (ex));
if (badMID(N_GETMID(ex)) && badMID(N_GETMID(ex_swap)))
return -1;
if (mid == -1) {
mid = getMID(mid, N_GETMID (ex_swap));
}
if (mid != -1) {
return(0);
} else {
return(-1);
}
return 0;
#endif /* NOAOUT */
}
@@ -675,38 +649,30 @@ GetAOutFileInfo(struct dllist *dl)
#ifdef NOAOUT
return(-1);
#else
struct exec ex, ex_swap;
u_int32_t mid = -1;
u_int32_t mid;
u_int32_t magic, clbytes, clofset;
struct exec ex, ex_swap;
(void)lseek(dl->ldfd, (off_t) 0, SEEK_SET);
if (read(dl->ldfd, (char *)&ex, sizeof(ex)) != sizeof(ex))
return(-1);
(void)lseek(dl->ldfd, (off_t) 0, SEEK_SET);
if (read(dl->ldfd, (char *)&ex_swap,
sizeof(ex_swap)) != sizeof(ex_swap))
return(-1);
memcpy(&ex_swap, &ex, sizeof(ex));
mopFileSwapX((u_char *)&ex_swap, 0, 4);
mid = getMID(mid, N_GETMID (ex));
if (mid == (uint32_t)-1) {
mid = getMID(mid, N_GETMID (ex_swap));
if (mid != (uint32_t)-1) {
mopFileSwapX((u_char *)&ex, 0, 4);
}
}
if (mid == (uint32_t)-1) {
return(-1);
}
// XXX Does swapped magic always imply swapped MID?
if (N_BADMAG (ex)) {
return(-1);
if (N_BADMAG (ex_swap))
return -1;
mid = N_GETMID(ex_swap);
} else {
mid = N_GETMID(ex);
}
if (badMID(mid))
return -1;
switch (mid) {
case MID_I386:
#ifdef MID_NS32532