Commit | Line | Data |
---|---|---|
505bf312 | 1 | /*- |
2839532b KB |
2 | * Copyright (c) 1980, 1993 |
3 | * The Regents of the University of California. All rights reserved. | |
505bf312 KB |
4 | * |
5 | * %sccs.include.redist.c% | |
f644bb55 | 6 | */ |
fa1f8751 | 7 | |
f644bb55 | 8 | #ifndef lint |
2839532b | 9 | static char sccsid[] = "@(#)ptrace.c 8.1 (Berkeley) %G%"; |
505bf312 | 10 | #endif /* not lint */ |
7838db54 ML |
11 | |
12 | /* | |
13 | * routines for tracing the execution of a process | |
14 | * | |
15 | * The system call "ptrace" does all the work, these | |
16 | * routines just try to interface easily to it. | |
17 | */ | |
18 | ||
19 | #include "defs.h" | |
20 | #include <signal.h> | |
21 | #include <sys/param.h> | |
f3338386 | 22 | #include <machine/reg.h> |
7838db54 ML |
23 | #include "process.h" |
24 | #include "object.h" | |
25 | #include "process.rep" | |
26 | ||
f9e6f1f3 | 27 | # include "pxinfo.h" |
7838db54 | 28 | |
82d3cd01 | 29 | #ifdef mc68000 |
fa1f8751 ML |
30 | # define U_PAGE 0x2400 |
31 | # define U_AR0 (14*sizeof(int)) | |
32 | LOCAL int ar0val = -1; | |
33 | #endif | |
34 | ||
7838db54 ML |
35 | /* |
36 | * This magic macro enables us to look at the process' registers | |
37 | * in its user structure. Very gross. | |
38 | */ | |
39 | ||
82d3cd01 | 40 | #if defined(vax) || defined(tahoe) |
fa1f8751 ML |
41 | # define regloc(reg) (ctob(UPAGES) + ( sizeof(int) * (reg) )) |
42 | #else | |
43 | # define regloc(reg) (ar0val + ( sizeof(int) * (reg) )) | |
44 | #endif | |
7838db54 | 45 | |
f9e6f1f3 ML |
46 | #define WMASK (~(sizeof(WORD) - 1)) |
47 | #define cachehash(addr) ((unsigned) ((addr >> 2) % CSIZE)) | |
7838db54 | 48 | |
f9e6f1f3 ML |
49 | #define ischild(pid) ((pid) == 0) |
50 | #define traceme() ptrace(0, 0, 0, 0) | |
51 | #define setrep(n) (1 << ((n)-1)) | |
52 | #define istraced(p) (p->sigset&setrep(p->signo)) | |
7838db54 ML |
53 | |
54 | /* | |
55 | * ptrace options (specified in first argument) | |
56 | */ | |
57 | ||
f9e6f1f3 ML |
58 | #define UREAD 3 /* read from process's user structure */ |
59 | #define UWRITE 6 /* write to process's user structure */ | |
60 | #define IREAD 1 /* read from process's instruction space */ | |
61 | #define IWRITE 4 /* write to process's instruction space */ | |
62 | #define DREAD 2 /* read from process's data space */ | |
63 | #define DWRITE 5 /* write to process's data space */ | |
64 | #define CONT 7 /* continue stopped process */ | |
65 | #define SSTEP 9 /* continue for approximately one instruction */ | |
66 | #define PKILL 8 /* terminate the process */ | |
7838db54 ML |
67 | |
68 | /* | |
69 | * Start up a new process by forking and exec-ing the | |
70 | * given argument list, returning when the process is loaded | |
71 | * and ready to execute. The PROCESS information (pointed to | |
72 | * by the first argument) is appropriately filled. | |
73 | * | |
74 | * If the given PROCESS structure is associated with an already running | |
75 | * process, we terminate it. | |
76 | */ | |
77 | ||
78 | /* VARARGS2 */ | |
33ece7d5 | 79 | pstart(p, cmd, argv, infile, outfile) |
7838db54 | 80 | PROCESS *p; |
33ece7d5 | 81 | char *cmd; |
7838db54 ML |
82 | char **argv; |
83 | char *infile; | |
84 | char *outfile; | |
85 | { | |
f9e6f1f3 ML |
86 | int status; |
87 | FILE *in, *out; | |
88 | ||
89 | if (p->pid != 0) { /* child already running? */ | |
90 | ptrace(PKILL, p->pid, 0, 0); /* ... kill it! */ | |
91 | } | |
85c677b9 | 92 | #ifdef tahoe |
82d3cd01 | 93 | INTFP = (ADDRESS)0; |
85c677b9 | 94 | #endif tahoe |
f9e6f1f3 ML |
95 | psigtrace(p, SIGTRAP, TRUE); |
96 | if ((p->pid = fork()) == -1) { | |
97 | panic("can't fork"); | |
98 | } | |
99 | if (ischild(p->pid)) { | |
100 | traceme(); | |
101 | if (infile != NIL) { | |
102 | if ((in = fopen(infile, "r")) == NIL) { | |
103 | printf("can't read %s\n", infile); | |
104 | exit(1); | |
105 | } | |
106 | fswap(0, fileno(in)); | |
7838db54 | 107 | } |
f9e6f1f3 ML |
108 | if (outfile != NIL) { |
109 | if ((out = fopen(outfile, "w")) == NIL) { | |
110 | printf("can't write %s\n", outfile); | |
111 | exit(1); | |
112 | } | |
113 | fswap(1, fileno(out)); | |
7838db54 | 114 | } |
f9e6f1f3 ML |
115 | execvp(cmd, argv); |
116 | panic("can't exec %s", argv[0]); | |
117 | } | |
118 | pwait(p->pid, &status); | |
119 | getinfo(p, status); | |
7838db54 ML |
120 | } |
121 | ||
122 | /* | |
123 | * Continue a stopped process. The argument points to a PROCESS structure. | |
124 | * Before the process is restarted it's user area is modified according to | |
125 | * the values in the structure. When this routine finishes, | |
126 | * the structure has the new values from the process's user area. | |
127 | * | |
128 | * Pcont terminates when the process stops with a signal pending that | |
129 | * is being traced (via psigtrace), or when the process terminates. | |
130 | */ | |
131 | ||
132 | pcont(p) | |
133 | PROCESS *p; | |
134 | { | |
f9e6f1f3 | 135 | int status; |
7838db54 | 136 | |
f9e6f1f3 ML |
137 | if (p->pid == 0) { |
138 | error("program not active"); | |
139 | } | |
140 | do { | |
141 | setinfo(p); | |
142 | sigs_off(); | |
143 | if (ptrace(CONT, p->pid, p->pc, p->signo) < 0) { | |
144 | panic("can't continue process"); | |
7838db54 | 145 | } |
f9e6f1f3 ML |
146 | pwait(p->pid, &status); |
147 | sigs_on(); | |
148 | getinfo(p, status); | |
149 | } while (p->status == STOPPED && !istraced(p)); | |
7838db54 ML |
150 | } |
151 | ||
152 | /* | |
153 | * single step as best ptrace can | |
154 | */ | |
155 | ||
156 | pstep(p) | |
157 | PROCESS *p; | |
158 | { | |
f9e6f1f3 ML |
159 | int status; |
160 | ||
161 | setinfo(p); | |
162 | sigs_off(); | |
163 | ptrace(SSTEP, p->pid, p->pc, p->signo); | |
164 | pwait(p->pid, &status); | |
165 | sigs_on(); | |
166 | getinfo(p, status); | |
7838db54 ML |
167 | } |
168 | ||
169 | /* | |
170 | * Return from execution when the given signal is pending. | |
171 | */ | |
172 | ||
173 | psigtrace(p, sig, sw) | |
174 | PROCESS *p; | |
175 | int sig; | |
176 | int sw; | |
177 | { | |
f9e6f1f3 ML |
178 | if (sw) { |
179 | p->sigset |= setrep(sig); | |
180 | } else { | |
181 | p->sigset &= ~setrep(sig); | |
182 | } | |
7838db54 ML |
183 | } |
184 | ||
185 | /* | |
186 | * Don't catch any signals. | |
187 | * Particularly useful when letting a process finish uninhibited (i.e. px). | |
188 | */ | |
189 | ||
190 | unsetsigtraces(p) | |
191 | PROCESS *p; | |
192 | { | |
f9e6f1f3 | 193 | p->sigset = 0; |
7838db54 ML |
194 | } |
195 | ||
196 | /* | |
197 | * turn off attention to signals not being caught | |
198 | */ | |
199 | ||
8e41b0ae | 200 | LOCAL void *onintr, *onquit; |
7838db54 ML |
201 | |
202 | LOCAL sigs_off() | |
203 | { | |
82d3cd01 KM |
204 | onintr = signal(SIGINT, SIG_IGN); |
205 | onquit = signal(SIGQUIT, SIG_IGN); | |
7838db54 ML |
206 | } |
207 | ||
208 | /* | |
209 | * turn back on attention to signals | |
210 | */ | |
211 | ||
212 | LOCAL sigs_on() | |
213 | { | |
82d3cd01 KM |
214 | (void) signal(SIGINT, onintr); |
215 | (void) signal(SIGQUIT, onquit); | |
7838db54 ML |
216 | } |
217 | ||
218 | /* | |
219 | * get PROCESS information from process's user area | |
220 | */ | |
221 | ||
fa1f8751 ML |
222 | #if vax |
223 | LOCAL int rloc[] ={ | |
224 | R0, R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, | |
225 | }; | |
82d3cd01 KM |
226 | #endif |
227 | #if tahoe | |
228 | LOCAL int rloc[] ={ | |
229 | R0, R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, | |
230 | }; | |
231 | #endif | |
232 | #if mc68000 | |
fa1f8751 ML |
233 | LOCAL int rloc[] ={ |
234 | R0, R1, R2, R3, R4, R5, R6, R7, AR0, AR1, AR2, AR3, AR4, AR5, | |
235 | }; | |
236 | #endif | |
7838db54 ML |
237 | |
238 | LOCAL getinfo(p, status) | |
239 | register PROCESS *p; | |
240 | register int status; | |
241 | { | |
f9e6f1f3 ML |
242 | register int i; |
243 | ||
244 | p->signo = (status&0177); | |
245 | p->exitval = ((status >> 8)&0377); | |
246 | if (p->signo == STOPPED) { | |
247 | p->status = p->signo; | |
248 | p->signo = p->exitval; | |
249 | p->exitval = 0; | |
250 | } else { | |
251 | p->status = FINISHED; | |
252 | return; | |
253 | } | |
82d3cd01 | 254 | #if !defined(vax) && !defined(tahoe) |
fa1f8751 ML |
255 | if (ar0val < 0){ |
256 | ar0val = ptrace(UREAD, p->pid, U_AR0, 0); | |
257 | ar0val -= U_PAGE; | |
258 | } | |
259 | #endif | |
f9e6f1f3 ML |
260 | for (i = 0; i < NREG; i++) { |
261 | p->reg[i] = ptrace(UREAD, p->pid, regloc(rloc[i]), 0); | |
262 | p->oreg[i] = p->reg[i]; | |
263 | } | |
82d3cd01 | 264 | #if defined(vax) || defined(tahoe) |
f9e6f1f3 | 265 | p->fp = p->ofp = ptrace(UREAD, p->pid, regloc(FP), 0); |
f9e6f1f3 ML |
266 | p->sp = p->osp = ptrace(UREAD, p->pid, regloc(SP), 0); |
267 | p->pc = p->opc = ptrace(UREAD, p->pid, regloc(PC), 0); | |
82d3cd01 KM |
268 | #endif |
269 | #ifdef vax | |
270 | p->ap = p->oap = ptrace(UREAD, p->pid, regloc(AP), 0); | |
271 | #endif | |
272 | #ifdef mc68000 | |
fa1f8751 ML |
273 | p->fp = p->ofp = ptrace(UREAD, p->pid, regloc(AR6), 0); |
274 | p->ap = p->oap = p->fp; | |
275 | p->sp = p->osp = ptrace(UREAD, p->pid, regloc(SP), 0); | |
276 | p->pc = p->opc = ptrace(UREAD, p->pid, regloc(PC), 0); | |
277 | #endif | |
7838db54 ML |
278 | } |
279 | ||
280 | /* | |
281 | * set process's user area information from given PROCESS structure | |
282 | */ | |
283 | ||
284 | LOCAL setinfo(p) | |
285 | register PROCESS *p; | |
286 | { | |
f9e6f1f3 ML |
287 | register int i; |
288 | register int r; | |
289 | ||
290 | if (istraced(p)) { | |
291 | p->signo = 0; | |
292 | } | |
293 | for (i = 0; i < NREG; i++) { | |
294 | if ((r = p->reg[i]) != p->oreg[i]) { | |
295 | ptrace(UWRITE, p->pid, regloc(rloc[i]), r); | |
7838db54 | 296 | } |
f9e6f1f3 | 297 | } |
82d3cd01 | 298 | #if vax || tahoe |
f9e6f1f3 ML |
299 | if ((r = p->fp) != p->ofp) { |
300 | ptrace(UWRITE, p->pid, regloc(FP), r); | |
301 | } | |
82d3cd01 KM |
302 | #endif |
303 | #if vax | |
f9e6f1f3 ML |
304 | if ((r = p->ap) != p->oap) { |
305 | ptrace(UWRITE, p->pid, regloc(AP), r); | |
306 | } | |
82d3cd01 KM |
307 | #endif |
308 | #if mc68000 | |
fa1f8751 ML |
309 | if ((r = p->fp) != p->ofp) { |
310 | ptrace(UWRITE, p->pid, regloc(AR6), r); | |
311 | } | |
82d3cd01 | 312 | #endif |
fa1f8751 ML |
313 | if ((r = p->sp) != p->osp) { |
314 | ptrace(UWRITE, p->pid, regloc(SP), r); | |
315 | } | |
f9e6f1f3 ML |
316 | if ((r = p->pc) != p->opc) { |
317 | ptrace(UWRITE, p->pid, regloc(PC), r); | |
318 | } | |
7838db54 ML |
319 | } |
320 | ||
321 | /* | |
322 | * Structure for reading and writing by words, but dealing with bytes. | |
323 | */ | |
324 | ||
325 | typedef union { | |
f9e6f1f3 ML |
326 | WORD pword; |
327 | BYTE pbyte[sizeof(WORD)]; | |
7838db54 ML |
328 | } PWORD; |
329 | ||
330 | /* | |
331 | * Read (write) from (to) the process' address space. | |
332 | * We must deal with ptrace's inability to look anywhere other | |
333 | * than at a word boundary. | |
334 | */ | |
335 | ||
336 | LOCAL WORD fetch(); | |
337 | LOCAL store(); | |
338 | ||
339 | pio(p, op, seg, buff, addr, nbytes) | |
340 | PROCESS *p; | |
341 | PIO_OP op; | |
342 | PIO_SEG seg; | |
343 | char *buff; | |
344 | ADDRESS addr; | |
345 | int nbytes; | |
346 | { | |
82d3cd01 | 347 | register int i, k; |
f9e6f1f3 ML |
348 | register ADDRESS newaddr; |
349 | register char *cp; | |
350 | char *bufend; | |
351 | PWORD w; | |
352 | ADDRESS wordaddr; | |
353 | int byteoff; | |
354 | ||
355 | if (p->status != STOPPED) { | |
356 | error("program is not active"); | |
357 | } | |
358 | cp = buff; | |
359 | newaddr = addr; | |
360 | wordaddr = (newaddr&WMASK); | |
361 | if (wordaddr != newaddr) { | |
362 | w.pword = fetch(p, seg, wordaddr); | |
363 | for (i = newaddr - wordaddr; i<sizeof(WORD) && nbytes>0; i++) { | |
364 | if (op == PREAD) { | |
365 | *cp++ = w.pbyte[i]; | |
366 | } else { | |
367 | w.pbyte[i] = *cp++; | |
368 | } | |
369 | nbytes--; | |
7838db54 | 370 | } |
f9e6f1f3 ML |
371 | if (op == PWRITE) { |
372 | store(p, seg, wordaddr, w.pword); | |
7838db54 | 373 | } |
f9e6f1f3 ML |
374 | newaddr = wordaddr + sizeof(WORD); |
375 | } | |
376 | byteoff = (nbytes&(~WMASK)); | |
377 | nbytes -= byteoff; | |
378 | bufend = cp + nbytes; | |
379 | while (cp < bufend) { | |
380 | if (op == PREAD) { | |
82d3cd01 KM |
381 | w.pword = fetch(p, seg, newaddr); |
382 | for (k = 0; k < sizeof(WORD); k++) { | |
383 | *cp++ = w.pbyte[k]; | |
384 | } | |
f9e6f1f3 | 385 | } else { |
82d3cd01 KM |
386 | for (k = 0; k < sizeof(WORD); k++) { |
387 | w.pbyte[k] = *cp++; | |
388 | } | |
389 | store(p, seg, newaddr, w.pword); | |
7838db54 | 390 | } |
f9e6f1f3 ML |
391 | newaddr += sizeof(WORD); |
392 | } | |
393 | if (byteoff > 0) { | |
394 | w.pword = fetch(p, seg, newaddr); | |
395 | for (i = 0; i < byteoff; i++) { | |
396 | if (op == PREAD) { | |
397 | *cp++ = w.pbyte[i]; | |
398 | } else { | |
399 | w.pbyte[i] = *cp++; | |
400 | } | |
7838db54 | 401 | } |
f9e6f1f3 ML |
402 | if (op == PWRITE) { |
403 | store(p, seg, newaddr, w.pword); | |
404 | } | |
405 | } | |
7838db54 ML |
406 | } |
407 | ||
408 | /* | |
409 | * Get a word from a process at the given address. | |
410 | * The address is assumed to be on a word boundary. | |
411 | * | |
412 | * We use a simple cache scheme to avoid redundant references to | |
413 | * the instruction space (which is assumed to be pure). In the | |
414 | * case of px, the "instruction" space lies between ENDOFF and | |
415 | * ENDOFF + objsize. | |
416 | * | |
417 | * It is necessary to use a write-through scheme so that | |
418 | * breakpoints right next to each other don't interfere. | |
419 | */ | |
420 | ||
421 | LOCAL WORD fetch(p, seg, addr) | |
422 | PROCESS *p; | |
423 | PIO_SEG seg; | |
424 | register int addr; | |
425 | { | |
f9e6f1f3 ML |
426 | register CACHEWORD *wp; |
427 | register WORD w; | |
428 | ||
429 | switch (seg) { | |
430 | case TEXTSEG: | |
82d3cd01 KM |
431 | panic("tried to fetch from px i-space"); |
432 | /* NOTREACHED */ | |
433 | ||
434 | case DATASEG: | |
435 | if (addr >= ENDOFF && addr < ENDOFF + objsize) { | |
f9e6f1f3 ML |
436 | wp = &p->word[cachehash(addr)]; |
437 | if (addr == 0 || wp->addr != addr) { | |
82d3cd01 | 438 | w = ptrace(DREAD, p->pid, addr, 0); |
f9e6f1f3 ML |
439 | wp->addr = addr; |
440 | wp->val = w; | |
441 | } else { | |
442 | w = wp->val; | |
443 | } | |
82d3cd01 | 444 | } else { |
f9e6f1f3 | 445 | w = ptrace(DREAD, p->pid, addr, 0); |
82d3cd01 | 446 | } |
f9e6f1f3 ML |
447 | break; |
448 | ||
449 | default: | |
450 | panic("fetch: bad seg %d", seg); | |
451 | /* NOTREACHED */ | |
452 | } | |
453 | return(w); | |
7838db54 ML |
454 | } |
455 | ||
456 | /* | |
457 | * Put a word into the process' address space at the given address. | |
458 | * The address is assumed to be on a word boundary. | |
459 | */ | |
460 | ||
461 | LOCAL store(p, seg, addr, data) | |
462 | PROCESS *p; | |
463 | PIO_SEG seg; | |
464 | int addr; | |
465 | WORD data; | |
466 | { | |
f9e6f1f3 ML |
467 | register CACHEWORD *wp; |
468 | ||
469 | switch (seg) { | |
470 | case TEXTSEG: | |
471 | wp = &p->word[cachehash(addr)]; | |
472 | wp->addr = addr; | |
473 | wp->val = data; | |
474 | ptrace(IWRITE, p->pid, addr, data); | |
475 | break; | |
476 | ||
477 | case DATASEG: | |
82d3cd01 KM |
478 | if (addr >= ENDOFF && addr < ENDOFF + objsize) { |
479 | wp = &p->word[cachehash(addr)]; | |
480 | wp->addr = addr; | |
481 | wp->val = data; | |
482 | } | |
f9e6f1f3 ML |
483 | ptrace(DWRITE, p->pid, addr, data); |
484 | break; | |
485 | ||
486 | default: | |
487 | panic("store: bad seg %d", seg); | |
488 | /*NOTREACHED*/ | |
489 | } | |
490 | } | |
7838db54 | 491 | |
f9e6f1f3 ML |
492 | /* |
493 | * Initialize the instruction cache for a process. | |
494 | * This is particularly necessary after the program has been remade. | |
495 | */ | |
496 | ||
497 | initcache(process) | |
498 | PROCESS *process; | |
499 | { | |
500 | register int i; | |
501 | ||
502 | for (i = 0; i < CSIZE; i++) { | |
503 | process->word[i].addr = 0; | |
504 | } | |
7838db54 ML |
505 | } |
506 | ||
507 | /* | |
508 | * Swap file numbers so as to redirect standard input and output. | |
509 | */ | |
510 | ||
511 | LOCAL fswap(oldfd, newfd) | |
512 | int oldfd; | |
513 | int newfd; | |
514 | { | |
f9e6f1f3 ML |
515 | if (oldfd != newfd) { |
516 | close(oldfd); | |
517 | dup(newfd); | |
518 | close(newfd); | |
519 | } | |
7838db54 | 520 | } |
82d3cd01 KM |
521 | |
522 | #ifdef tahoe | |
523 | BOOLEAN didret; | |
524 | ||
525 | void | |
526 | chkret(p, status) | |
527 | PROCESS *p; | |
528 | int status; | |
529 | { | |
530 | if (((status == (SIGILL << 8) | STOPPED) || | |
531 | (status == (SIGTRAP << 8) | STOPPED))) { | |
532 | didret = FALSE; | |
533 | } else { | |
534 | didret = TRUE; | |
535 | } | |
536 | } | |
537 | ||
538 | void | |
539 | doret(p) | |
540 | PROCESS *p; | |
541 | { | |
542 | register count = 0; | |
543 | ||
544 | if (!didret) { | |
545 | do { | |
546 | if (++count > 5) { | |
547 | panic("px would not return to interpreter"); | |
548 | } | |
549 | p->pc = RETLOC; | |
550 | pstep(p); | |
551 | } while(INTFP && p->fp != INTFP); | |
552 | didret = TRUE; | |
553 | } | |
554 | } | |
555 | #endif |