1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
|
/*
* 8obj.c - identify and parse a 386 object file
*/
#include <u.h>
#include <libc.h>
#include <bio.h>
#include <mach.h>
#include "8c/8.out.h"
#include "obj.h"
typedef struct Addr Addr;
struct Addr
{
char sym;
char flags;
};
static Addr addr(Biobuf*);
static char type2char(int);
static void skip(Biobuf*, int);
int
_is8(char *t)
{
uchar *s = (uchar*)t;
return s[0] == (ANAME&0xff) /* aslo = ANAME */
&& s[1] == ((ANAME>>8)&0xff)
&& s[2] == D_FILE /* type */
&& s[3] == 1 /* sym */
&& s[4] == '<'; /* name of file */
}
int
_read8(Biobuf *bp, Prog* p)
{
int as, n, c;
Addr a;
as = Bgetc(bp); /* as(low) */
if(as < 0)
return 0;
c = Bgetc(bp); /* as(high) */
if(c < 0)
return 0;
as |= ((c & 0xff) << 8);
p->kind = aNone;
p->sig = 0;
if(as == ANAME || as == ASIGNAME){
if(as == ASIGNAME){
Bread(bp, &p->sig, 4);
p->sig = leswal(p->sig);
}
p->kind = aName;
p->type = type2char(Bgetc(bp)); /* type */
p->sym = Bgetc(bp); /* sym */
n = 0;
for(;;) {
as = Bgetc(bp);
if(as < 0)
return 0;
n++;
if(as == 0)
break;
}
p->id = malloc(n);
if(p->id == 0)
return 0;
Bseek(bp, -n, 1);
if(Bread(bp, p->id, n) != n)
return 0;
return 1;
}
if(as == ATEXT)
p->kind = aText;
if(as == AGLOBL)
p->kind = aData;
skip(bp, 4); /* lineno(4) */
a = addr(bp);
addr(bp);
if(!(a.flags & T_SYM))
p->kind = aNone;
p->sym = a.sym;
return 1;
}
static Addr
addr(Biobuf *bp)
{
Addr a;
int t;
long off;
off = 0;
a.sym = -1;
a.flags = Bgetc(bp); /* flags */
if(a.flags & T_INDEX)
skip(bp, 2);
if(a.flags & T_OFFSET){
off = Bgetc(bp);
off |= Bgetc(bp) << 8;
off |= Bgetc(bp) << 16;
off |= Bgetc(bp) << 24;
if(off < 0)
off = -off;
}
if(a.flags & T_SYM)
a.sym = Bgetc(bp);
if(a.flags & T_FCONST)
skip(bp, 8);
else
if(a.flags & T_SCONST)
skip(bp, NSNAME);
if(a.flags & T_TYPE) {
t = Bgetc(bp);
if(a.sym > 0 && (t==D_PARAM || t==D_AUTO))
_offset(a.sym, off);
}
return a;
}
static char
type2char(int t)
{
switch(t){
case D_EXTERN: return 'U';
case D_STATIC: return 'b';
case D_AUTO: return 'a';
case D_PARAM: return 'p';
default: return UNKNOWN;
}
}
static void
skip(Biobuf *bp, int n)
{
while (n-- > 0)
Bgetc(bp);
}
|
