1 /*
2 * 7obj.c - identify and parse an alpha object file
3 */
4 #include <u.h>
5 #include <libc.h>
6 #include <bio.h>
7 #include <mach.h>
8 #include "alpha/7.out.h"
9 #include "obj.h"
10
11 typedef struct Addr Addr;
12 struct Addr
13 {
14 char type;
15 char sym;
16 char name;
17 };
18 static Addr addr(Biobuf*);
19 static char type2char(int);
20 static void skip(Biobuf*, int);
21
22 int
_is7(char * s)23 _is7(char *s)
24 {
25 return s[0] == ANAME /* ANAME */
26 && s[1] == D_FILE /* type */
27 && s[2] == 1 /* sym */
28 && s[3] == '<'; /* name of file */
29 }
30
31 int
_read7(Biobuf * bp,Prog * p)32 _read7(Biobuf *bp, Prog *p)
33 {
34 int as, n;
35 Addr a;
36
37 as = Bgetc(bp); /* as */
38 if(as < 0)
39 return 0;
40 p->kind = aNone;
41 p->sig = 0;
42 if(as == ANAME || as == ASIGNAME){
43 if(as == ASIGNAME){
44 Bread(bp, &p->sig, 4);
45 p->sig = leswal(p->sig);
46 }
47 p->kind = aName;
48 p->type = type2char(Bgetc(bp)); /* type */
49 p->sym = Bgetc(bp); /* sym */
50 n = 0;
51 for(;;) {
52 as = Bgetc(bp);
53 if(as < 0)
54 return 0;
55 n++;
56 if(as == 0)
57 break;
58 }
59 p->id = malloc(n);
60 if(p->id == 0)
61 return 0;
62 Bseek(bp, -n, 1);
63 if(Bread(bp, p->id, n) != n)
64 return 0;
65 return 1;
66 }
67 if(as == ATEXT)
68 p->kind = aText;
69 else if(as == AGLOBL)
70 p->kind = aData;
71 skip(bp, 5); /* reg(1), lineno(4) */
72 a = addr(bp);
73 addr(bp);
74 if(a.type != D_OREG || a.name != D_STATIC && a.name != D_EXTERN)
75 p->kind = aNone;
76 p->sym = a.sym;
77 return 1;
78 }
79
80 static Addr
addr(Biobuf * bp)81 addr(Biobuf *bp)
82 {
83 Addr a;
84 vlong off;
85
86 a.type = Bgetc(bp); /* a.type */
87 skip(bp,1); /* reg */
88 a.sym = Bgetc(bp); /* sym index */
89 a.name = Bgetc(bp); /* sym type */
90 switch(a.type){
91 default:
92 case D_NONE: case D_REG: case D_FREG: case D_PREG:
93 case D_FCREG: case D_PCC:
94 break;
95 case D_OREG:
96 case D_CONST:
97 case D_BRANCH:
98 off = (uvlong)Bgetc(bp);
99 off |= (uvlong)Bgetc(bp) << 8;
100 off |= (uvlong)Bgetc(bp) << 16;
101 off |= (uvlong)Bgetc(bp) << 24;
102 off |= (uvlong)Bgetc(bp) << 32;
103 off |= (uvlong)Bgetc(bp) << 40;
104 off |= (uvlong)Bgetc(bp) << 48;
105 off |= (uvlong)Bgetc(bp) << 56;
106 if(off < 0)
107 off = -off;
108 if(a.sym && (a.name==D_PARAM || a.name==D_AUTO))
109 _offset(a.sym, off);
110 break;
111 case D_SCONST:
112 skip(bp, NSNAME);
113 break;
114 case D_FCONST:
115 skip(bp, 8);
116 break;
117 }
118 return a;
119 }
120
121 static char
type2char(int t)122 type2char(int t)
123 {
124 switch(t){
125 case D_EXTERN: return 'U';
126 case D_STATIC: return 'b';
127 case D_AUTO: return 'a';
128 case D_PARAM: return 'p';
129 default: return UNKNOWN;
130 }
131 }
132
133 static void
skip(Biobuf * bp,int n)134 skip(Biobuf *bp, int n)
135 {
136 while (n-- > 0)
137 Bgetc(bp);
138 }
139