John Gilmore's version of the automaton.

diff --git a/src/softmagic.c b/src/softmagic.c
index 6cb7d9145d11453e8b4db1504e5809a8091b7f43..b6e45a050d703e14631c43f3a5d6841da93e88d3 100644 (file)
--- a/src/softmagic.c
+++ b/src/softmagic.c
@@ -86,13 +86,14 @@ char *s;
        }
 }
 
+int
 mcheck(s, m)
 char   *s;
 struct magic *m;
 {
-       register char reln = m->reln;
        register union VALUETYPE *p = (union VALUETYPE *)(s+m->offset);
        register long l = m->value.l;
+       register long v;
 
        if (debug) {
                (void) printf("mcheck: %10.10s ", s);
@@ -100,49 +101,42 @@ struct magic *m;
        }
        switch (m->type) {
        case BYTE:
-               if (reln == '>')
-                       return p->b > l;
-               if (reln == '&')
-                       return l & p->b;
-               if (reln == '=')
-                       return l == p->b;
-               warning("mcheck: can't happen: invalid BYTE reln %d", reln);
-               return 0;
+               v = p->b; break;
        case SHORT:
-               if (reln == '=')
-                       return l == p->h;
-               if (reln == '>')
-                       return p->h > l;
-               if (reln == '&')
-                       return l & p->h;
-               warning("mcheck: can't happen: invalid SHORT reln %d", reln);
-               return 0;
+               v = p->h; break;
        case LONG:
-               if (reln == '=')
-                       return l == p->l;
-               if (reln == '>')
-                       return p->l > l;
-               if (reln == '&')
-                       return l & p->l;
-               warning("mcheck: can't happen: invalid LONG reln %d", reln);
-               return 0;
+               v = p->l; break;
        case STRING:
-               if (reln == '=')
-                       return strncmp(m->value.s, p->s,
-                               strlen(m->value.s)) == 0;
-               if (reln == '>')
-                       if (strcmp(m->value.s, "0") == 0) /* special case! */
-                               return *s > '\0';
-                       else
-                               return strncmp(m->value.s, p->s,
-                                       strlen(m->value.s)) > 0;
-               warning("mcheck: can't happen: invalid STRING reln %c(0%o)",
-                       reln, reln);
-               return 0;
+               l = 0;
+               /* What we want here is:
+                * v = strncmp(m->value.s, p->s, m->vallen);
+                * but ignoring any nulls.  bcmp doesn't give -/+/0.
+                */
+               {
+                       register unsigned char *a = (unsigned char*)m->value.s;
+                       register unsigned char *b = (unsigned char*)p->s;
+                       register int len = m->vallen;
+
+                       while (--len >= 0)
+                               if (0 != (v = *b++ - *a++)) break;
+               }
+               break;
        default:
                warning("invalid type %d in mcheck()", m->type);
                return 0;
        }
-}
-
 
+       switch (m->reln) {
+       case '=':
+               return v == l;
+       case '>':
+               return v > l;
+       case '<':
+               return v < l;
+       case '&':
+               return v & l;
+       default:
+               warning("mcheck: can't happen: invalid relation %d", m->reln);
+               return 0;
+       }
+}