1 /* 2 * qobj.c - identify and parse a PowerPC object file 3 * forsyth@terzarima.net 4 */ 5 #include <lib9.h> 6 #include <bio.h> 7 #include "mach.h" 8 #include "qc/q.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 23 _isq(char *s) 24 { 25 return (s[0]&0377) == ANAME /* ANAME */ 26 && (s[1]&0377) == ANAME>>8 27 && s[2] == D_FILE /* type */ 28 && s[3] == 1 /* sym */ 29 && s[4] == '<'; /* name of file */ 30 } 31 32 int 33 _readq(Biobuf *bp, Prog *p) 34 { 35 int as, n, c; 36 Addr a; 37 38 as = Bgetc(bp); /* as(low) */ 39 if(as < 0) 40 return 0; 41 c = Bgetc(bp); /* as(high) */ 42 if(c < 0) 43 return 0; 44 as |= ((c & 0xff) << 8); 45 p->kind = aNone; 46 p->sig = 0; 47 if(as == ANAME || as == ASIGNAME){ 48 if(as == ASIGNAME){ 49 Bread(bp, &p->sig, 4); 50 p->sig = beswal(p->sig); 51 } 52 p->kind = aName; 53 p->type = type2char(Bgetc(bp)); /* type */ 54 p->sym = Bgetc(bp); /* sym */ 55 n = 0; 56 for(;;) { 57 as = Bgetc(bp); 58 if(as < 0) 59 return 0; 60 n++; 61 if(as == 0) 62 break; 63 } 64 p->id = malloc(n); 65 if(p->id == 0) 66 return 0; 67 Bseek(bp, -n, 1); 68 if(Bread(bp, p->id, n) != n) 69 return 0; 70 return 1; 71 } 72 if(as == ATEXT) 73 p->kind = aText; 74 else if(as == AGLOBL) 75 p->kind = aData; 76 n = Bgetc(bp); /* reg and flag */ 77 skip(bp, 4); /* lineno(4) */ 78 a = addr(bp); 79 if(n & 0x40) 80 addr(bp); 81 addr(bp); 82 if(a.type != D_OREG || a.name != D_STATIC && a.name != D_EXTERN) 83 p->kind = aNone; 84 p->sym = a.sym; 85 return 1; 86 } 87 88 static Addr 89 addr(Biobuf *bp) 90 { 91 Addr a; 92 long off; 93 94 a.type = Bgetc(bp); /* a.type */ 95 skip(bp,1); /* reg */ 96 a.sym = Bgetc(bp); /* sym index */ 97 a.name = Bgetc(bp); /* sym type */ 98 switch(a.type){ 99 default: 100 case D_NONE: case D_REG: case D_FREG: case D_CREG: 101 case D_FPSCR: case D_MSR: case D_SREG: 102 break; 103 case D_SPR: 104 case D_OREG: 105 case D_DCR: 106 case D_CONST: 107 case D_BRANCH: 108 off = Bgetc(bp); 109 off |= Bgetc(bp) << 8; 110 off |= Bgetc(bp) << 16; 111 off |= Bgetc(bp) << 24; 112 if(off < 0) 113 off = -off; 114 if(a.sym && (a.name==D_PARAM || a.name==D_AUTO)) 115 _offset(a.sym, off); 116 break; 117 case D_SCONST: 118 skip(bp, NSNAME); 119 break; 120 case D_FCONST: 121 skip(bp, 8); 122 break; 123 } 124 return a; 125 } 126 127 static char 128 type2char(int t) 129 { 130 switch(t){ 131 case D_EXTERN: return 'U'; 132 case D_STATIC: return 'b'; 133 case D_AUTO: return 'a'; 134 case D_PARAM: return 'p'; 135 default: return UNKNOWN; 136 } 137 } 138 139 static void 140 skip(Biobuf *bp, int n) 141 { 142 while (n-- > 0) 143 Bgetc(bp); 144 } 145