1 /*
2 * obj.c
3 * routines universal to all object files
4 */
5 #include <lib9.h>
6 #include <ctype.h>
7 #include <bio.h>
8 #include <ar.h>
9 #include "mach.h"
10 #include "obj.h"
11
12 #define islocal(t) ((t)=='a' || (t)=='p')
13
14 enum
15 {
16 NNAMES = 50,
17 MAXIS = 8, /* max length to determine if a file is a .? file */
18 MAXOFF = 0x7fffffff, /* larger than any possible local offset */
19 NHASH = 1024, /* must be power of two */
20 HASHMUL = 79L,
21 };
22
23 /* in [$OS].c */
24 int _is5(char*),
25 _is6(char*),
26 _is8(char*),
27 _is9(char*),
28 _isk(char*),
29 _isq(char*),
30 _isv(char*),
31 _isi(char*),
32 _read5(Biobuf*, Prog*),
33 _read6(Biobuf*, Prog*),
34 _read8(Biobuf*, Prog*),
35 _read9(Biobuf*, Prog*),
36 _readk(Biobuf*, Prog*),
37 _readq(Biobuf*, Prog*),
38 _readv(Biobuf*, Prog*),
39 _readi(Biobuf*, Prog*);
40
41 typedef struct Obj Obj;
42 typedef struct Symtab Symtab;
43
44 struct Obj /* functions to handle each intermediate (.$O) file */
45 {
46 char *name; /* name of each $O file */
47 int (*is)(char*); /* test for each type of $O file */
48 int (*read)(Biobuf*, Prog*); /* read for each type of $O file*/
49 };
50
51 static Obj obj[] =
52 { /* functions to identify and parse each type of obj */
53 /*[Obj68020]*/ {0, 0,},
54 /*[ObjSparc]*/ "sparc .k", _isk, _readk,
55 /*[ObjMips]*/ "mips .v", _isv, _readv,
56 /*[Obj386]*/ "386 .8", _is8, _read8,
57 /*[Obj960]*/ {0, 0,},
58 /*[Obj3210]*/ {0, 0,},
59 /*[ObjMips2]*/ {0, 0,},
60 /*[Obj29000]*/ {0, 0,},
61 /*[ObjArm]*/ "arm .5", _is5, _read5,
62 /*[ObjPower]*/ "power .q", _isq, _readq,
63 /*[ObjMips2le]*/ {0, 0,},
64 /*[ObjAlpha]*/ {0, 0,},
65 /*[ObjSparc64]*/ {0, 0,},
66 /*[ObjAmd64]*/ "amd64 .6", _is6, _read6,
67 /*[ObjSpim]*/ {0, 0,},
68 /*[ObjPower64]*/ "power64 .9", _is9, _read9,
69 /*[ObjRiscv]*/ "riscv .i", _isi, _readi,
70 /*[ObjRiscv64]*/ "riscv64 .j", _isi, _readi,
71 /*[Maxobjtype]*/ 0, 0
72 };
73
74 struct Symtab
75 {
76 struct Sym s;
77 struct Symtab *next;
78 };
79
80 static Symtab *hash[NHASH];
81 static Sym *names[NNAMES]; /* working set of active names */
82
83 static int processprog(Prog*,int); /* decode each symbol reference */
84 static void objreset(void);
85 static void objlookup(int, char *, int, uint);
86 static void objupdate(int, int);
87
88 int
objtype(Biobuf * bp,char ** name)89 objtype(Biobuf *bp, char **name)
90 {
91 int i;
92 char buf[MAXIS];
93
94 if(Bread(bp, buf, MAXIS) < MAXIS)
95 return -1;
96 Bseek(bp, -MAXIS, 1);
97 for (i = 0; i < Maxobjtype; i++) {
98 if (obj[i].is && (*obj[i].is)(buf)) {
99 if (name)
100 *name = obj[i].name;
101 return i;
102 }
103 }
104 return -1;
105 }
106
107 int
isar(Biobuf * bp)108 isar(Biobuf *bp)
109 {
110 int n;
111 char magbuf[SARMAG];
112
113 n = Bread(bp, magbuf, SARMAG);
114 if(n == SARMAG && strncmp(magbuf, ARMAG, SARMAG) == 0)
115 return 1;
116 return 0;
117 }
118
119 /*
120 * determine what kind of object file this is and process it.
121 * return whether or not this was a recognized intermediate file.
122 */
123 int
readobj(Biobuf * bp,int objtype)124 readobj(Biobuf *bp, int objtype)
125 {
126 Prog p;
127
128 if (objtype < 0 || objtype >= Maxobjtype || obj[objtype].is == 0)
129 return 1;
130 objreset();
131 while ((*obj[objtype].read)(bp, &p))
132 if (!processprog(&p, 1))
133 return 0;
134 return 1;
135 }
136
137 int
readar(Biobuf * bp,int objtype,vlong end,int doautos)138 readar(Biobuf *bp, int objtype, vlong end, int doautos)
139 {
140 Prog p;
141
142 if (objtype < 0 || objtype >= Maxobjtype || obj[objtype].is == 0)
143 return 1;
144 objreset();
145 while ((*obj[objtype].read)(bp, &p) && Boffset(bp) < end)
146 if (!processprog(&p, doautos))
147 return 0;
148 return 1;
149 }
150
151 /*
152 * decode a symbol reference or definition
153 */
154 static int
processprog(Prog * p,int doautos)155 processprog(Prog *p, int doautos)
156 {
157 if(p->kind == aNone)
158 return 1;
159 if(p->sym < 0 || p->sym >= NNAMES)
160 return 0;
161 switch(p->kind)
162 {
163 case aName:
164 if (!doautos)
165 if(p->type != 'U' && p->type != 'b')
166 break;
167 objlookup(p->sym, p->id, p->type, p->sig);
168 break;
169 case aText:
170 objupdate(p->sym, 'T');
171 break;
172 case aData:
173 objupdate(p->sym, 'D');
174 break;
175 default:
176 break;
177 }
178 return 1;
179 }
180
181 /*
182 * find the entry for s in the symbol array.
183 * make a new entry if it is not already there.
184 */
185 static void
objlookup(int id,char * name,int type,uint sig)186 objlookup(int id, char *name, int type, uint sig)
187 {
188 long h;
189 char *cp;
190 Sym *s;
191 Symtab *sp;
192
193 s = names[id];
194 if(s && strcmp(s->name, name) == 0) {
195 s->type = type;
196 s->sig = sig;
197 return;
198 }
199
200 h = *name;
201 for(cp = name+1; *cp; h += *cp++)
202 h *= HASHMUL;
203 if(h < 0)
204 h = ~h;
205 h &= (NHASH-1);
206 if (type == 'U' || type == 'b' || islocal(type)) {
207 for(sp = hash[h]; sp; sp = sp->next)
208 if(strcmp(sp->s.name, name) == 0) {
209 switch(sp->s.type) {
210 case 'T':
211 case 'D':
212 case 'U':
213 if (type == 'U') {
214 names[id] = &sp->s;
215 return;
216 }
217 break;
218 case 't':
219 case 'd':
220 case 'b':
221 if (type == 'b') {
222 names[id] = &sp->s;
223 return;
224 }
225 break;
226 case 'a':
227 case 'p':
228 if (islocal(type)) {
229 names[id] = &sp->s;
230 return;
231 }
232 break;
233 default:
234 break;
235 }
236 }
237 }
238 sp = malloc(sizeof(Symtab));
239 sp->s.name = name;
240 sp->s.type = type;
241 sp->s.sig = sig;
242 sp->s.value = islocal(type) ? MAXOFF : 0;
243 names[id] = &sp->s;
244 sp->next = hash[h];
245 hash[h] = sp;
246 return;
247 }
248 /*
249 * traverse the symbol lists
250 */
251 void
objtraverse(void (* fn)(Sym *,void *),void * pointer)252 objtraverse(void (*fn)(Sym*, void*), void *pointer)
253 {
254 int i;
255 Symtab *s;
256
257 for(i = 0; i < NHASH; i++)
258 for(s = hash[i]; s; s = s->next)
259 (*fn)(&s->s, pointer);
260 }
261
262 /*
263 * update the offset information for a 'a' or 'p' symbol in an intermediate file
264 */
265 void
_offset(int id,vlong off)266 _offset(int id, vlong off)
267 {
268 Sym *s;
269
270 s = names[id];
271 if (s && s->name[0] && islocal(s->type) && s->value > off)
272 s->value = off;
273 }
274
275 /*
276 * update the type of a global text or data symbol
277 */
278 static void
objupdate(int id,int type)279 objupdate(int id, int type)
280 {
281 Sym *s;
282
283 s = names[id];
284 if (s && s->name[0])
285 if (s->type == 'U')
286 s->type = type;
287 else if (s->type == 'b')
288 s->type = tolower(type);
289 }
290
291 /*
292 * look for the next file in an archive
293 */
294 int
nextar(Biobuf * bp,int offset,char * buf)295 nextar(Biobuf *bp, int offset, char *buf)
296 {
297 struct ar_hdr a;
298 int i, r;
299 long arsize;
300
301 if (offset&01)
302 offset++;
303 Bseek(bp, offset, 0);
304 r = Bread(bp, &a, SAR_HDR);
305 if(r != SAR_HDR)
306 return 0;
307 if(strncmp(a.fmag, ARFMAG, sizeof(a.fmag)))
308 return -1;
309 for(i=0; i<sizeof(a.name) && i<SARNAME && a.name[i] != ' '; i++)
310 buf[i] = a.name[i];
311 buf[i] = 0;
312 arsize = strtol(a.size, 0, 0);
313 if (arsize&1)
314 arsize++;
315 return arsize + SAR_HDR;
316 }
317
318 static void
objreset(void)319 objreset(void)
320 {
321 int i;
322 Symtab *s, *n;
323
324 for(i = 0; i < NHASH; i++) {
325 for(s = hash[i]; s; s = n) {
326 n = s->next;
327 free(s->s.name);
328 free(s);
329 }
330 hash[i] = 0;
331 }
332 memset(names, 0, sizeof names);
333 }
334