1 /* 2 * vobj.c - identify and parse a mips object file 3 */ 4 #include <lib9.h> 5 #include <bio.h> 6 #include "mach.h" 7 #include "vc/v.out.h" 8 #include "obj.h" 9 10 typedef struct Addr Addr; 11 struct Addr 12 { 13 char type; 14 char sym; 15 char name; 16 }; 17 static Addr addr(Biobuf*); 18 static char type2char(int); 19 static void skip(Biobuf*, int); 20 21 int 22 _isv(char *s) 23 { 24 return s[0] == ANAME /* ANAME */ 25 && s[1] == D_FILE /* type */ 26 && s[2] == 1 /* sym */ 27 && s[3] == '<'; /* name of file */ 28 } 29 30 int 31 _readv(Biobuf *bp, Prog *p) 32 { 33 int as, n; 34 Addr a; 35 36 as = Bgetc(bp); /* as */ 37 if(as < 0) 38 return 0; 39 p->kind = aNone; 40 p->sig = 0; 41 if(as == ANAME || as == ASIGNAME){ 42 if(as == ASIGNAME){ 43 Bread(bp, &p->sig, 4); 44 p->sig = leswal(p->sig); 45 } 46 p->kind = aName; 47 p->type = type2char(Bgetc(bp)); /* type */ 48 p->sym = Bgetc(bp); /* sym */ 49 n = 0; 50 for(;;) { 51 as = Bgetc(bp); 52 if(as < 0) 53 return 0; 54 n++; 55 if(as == 0) 56 break; 57 } 58 p->id = malloc(n); 59 if(p->id == 0) 60 return 0; 61 Bseek(bp, -n, 1); 62 if(Bread(bp, p->id, n) != n) 63 return 0; 64 return 1; 65 } 66 if(as == ATEXT) 67 p->kind = aText; 68 else if(as == AGLOBL) 69 p->kind = aData; 70 skip(bp, 5); /* reg(1), lineno(4) */ 71 a = addr(bp); 72 addr(bp); 73 if(a.type != D_OREG || a.name != D_STATIC && a.name != D_EXTERN) 74 p->kind = aNone; 75 p->sym = a.sym; 76 return 1; 77 } 78 79 static Addr 80 addr(Biobuf *bp) 81 { 82 Addr a; 83 long off; 84 85 a.type = Bgetc(bp); /* a.type */ 86 skip(bp,1); /* reg */ 87 a.sym = Bgetc(bp); /* sym index */ 88 a.name = Bgetc(bp); /* sym type */ 89 switch(a.type){ 90 default: 91 case D_NONE: case D_REG: case D_FREG: case D_MREG: 92 case D_FCREG: case D_LO: case D_HI: 93 break; 94 case D_OREG: 95 case D_CONST: 96 case D_BRANCH: 97 off = Bgetc(bp); 98 off |= Bgetc(bp) << 8; 99 off |= Bgetc(bp) << 16; 100 off |= Bgetc(bp) << 24; 101 if(off < 0) 102 off = -off; 103 if(a.sym && (a.name==D_PARAM || a.name==D_AUTO)) 104 _offset(a.sym, off); 105 break; 106 case D_SCONST: 107 skip(bp, NSNAME); 108 break; 109 case D_FCONST: 110 skip(bp, 8); 111 break; 112 } 113 return a; 114 } 115 116 static char 117 type2char(int t) 118 { 119 switch(t){ 120 case D_EXTERN: return 'U'; 121 case D_STATIC: return 'b'; 122 case D_AUTO: return 'a'; 123 case D_PARAM: return 'p'; 124 default: return UNKNOWN; 125 } 126 } 127 128 static void 129 skip(Biobuf *bp, int n) 130 { 131 while (n-- > 0) 132 Bgetc(bp); 133 } 134