xref: /titanic_41/usr/src/lib/libdtrace/common/dt_pid.c (revision e11c3f44f531fdff80941ce57c065d2ae861cefc)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #include <assert.h>
28 #include <strings.h>
29 #include <stdlib.h>
30 #include <stdio.h>
31 #include <errno.h>
32 #include <ctype.h>
33 #include <alloca.h>
34 #include <libgen.h>
35 #include <stddef.h>
36 
37 #include <dt_impl.h>
38 #include <dt_program.h>
39 #include <dt_pid.h>
40 #include <dt_string.h>
41 
42 typedef struct dt_pid_probe {
43 	dtrace_hdl_t *dpp_dtp;
44 	dt_pcb_t *dpp_pcb;
45 	dt_proc_t *dpp_dpr;
46 	struct ps_prochandle *dpp_pr;
47 	const char *dpp_mod;
48 	char *dpp_func;
49 	const char *dpp_name;
50 	const char *dpp_obj;
51 	uintptr_t dpp_pc;
52 	size_t dpp_size;
53 	Lmid_t dpp_lmid;
54 	uint_t dpp_nmatches;
55 	uint64_t dpp_stret[4];
56 	GElf_Sym dpp_last;
57 	uint_t dpp_last_taken;
58 } dt_pid_probe_t;
59 
60 /*
61  * Compose the lmid and object name into the canonical representation. We
62  * omit the lmid for the default link map for convenience.
63  */
64 static void
65 dt_pid_objname(char *buf, size_t len, Lmid_t lmid, const char *obj)
66 {
67 	if (lmid == LM_ID_BASE)
68 		(void) strncpy(buf, obj, len);
69 	else
70 		(void) snprintf(buf, len, "LM%lx`%s", lmid, obj);
71 }
72 
73 static int
74 dt_pid_error(dtrace_hdl_t *dtp, dt_pcb_t *pcb, dt_proc_t *dpr,
75     fasttrap_probe_spec_t *ftp, dt_errtag_t tag, const char *fmt, ...)
76 {
77 	va_list ap;
78 	int len;
79 
80 	if (ftp != NULL)
81 		dt_free(dtp, ftp);
82 
83 	va_start(ap, fmt);
84 	if (pcb == NULL) {
85 		assert(dpr != NULL);
86 		len = vsnprintf(dpr->dpr_errmsg, sizeof (dpr->dpr_errmsg),
87 		    fmt, ap);
88 		assert(len >= 2);
89 		if (dpr->dpr_errmsg[len - 2] == '\n')
90 			dpr->dpr_errmsg[len - 2] = '\0';
91 	} else {
92 		dt_set_errmsg(dtp, dt_errtag(tag), pcb->pcb_region,
93 		    pcb->pcb_filetag, pcb->pcb_fileptr ? yylineno : 0, fmt, ap);
94 	}
95 	va_end(ap);
96 
97 	return (1);
98 }
99 
100 static int
101 dt_pid_per_sym(dt_pid_probe_t *pp, const GElf_Sym *symp, const char *func)
102 {
103 	dtrace_hdl_t *dtp = pp->dpp_dtp;
104 	dt_pcb_t *pcb = pp->dpp_pcb;
105 	dt_proc_t *dpr = pp->dpp_dpr;
106 	fasttrap_probe_spec_t *ftp;
107 	uint64_t off;
108 	char *end;
109 	uint_t nmatches = 0;
110 	ulong_t sz;
111 	int glob, err;
112 	int isdash = strcmp("-", func) == 0;
113 	pid_t pid;
114 
115 	pid = Pstatus(pp->dpp_pr)->pr_pid;
116 
117 	dt_dprintf("creating probe pid%d:%s:%s:%s\n", (int)pid, pp->dpp_obj,
118 	    func, pp->dpp_name);
119 
120 	sz = sizeof (fasttrap_probe_spec_t) + (isdash ? 4 :
121 	    (symp->st_size - 1) * sizeof (ftp->ftps_offs[0]));
122 
123 	if ((ftp = dt_alloc(dtp, sz)) == NULL) {
124 		dt_dprintf("proc_per_sym: dt_alloc(%lu) failed\n", sz);
125 		return (1); /* errno is set for us */
126 	}
127 
128 	ftp->ftps_pid = pid;
129 	(void) strncpy(ftp->ftps_func, func, sizeof (ftp->ftps_func));
130 
131 	dt_pid_objname(ftp->ftps_mod, sizeof (ftp->ftps_mod), pp->dpp_lmid,
132 	    pp->dpp_obj);
133 
134 	if (!isdash && gmatch("return", pp->dpp_name)) {
135 		if (dt_pid_create_return_probe(pp->dpp_pr, dtp, ftp, symp,
136 		    pp->dpp_stret) < 0) {
137 			return (dt_pid_error(dtp, pcb, dpr, ftp,
138 			    D_PROC_CREATEFAIL, "failed to create return probe "
139 			    "for '%s': %s", func,
140 			    dtrace_errmsg(dtp, dtrace_errno(dtp))));
141 		}
142 
143 		nmatches++;
144 	}
145 
146 	if (!isdash && gmatch("entry", pp->dpp_name)) {
147 		if (dt_pid_create_entry_probe(pp->dpp_pr, dtp, ftp, symp) < 0) {
148 			return (dt_pid_error(dtp, pcb, dpr, ftp,
149 			    D_PROC_CREATEFAIL, "failed to create entry probe "
150 			    "for '%s': %s", func,
151 			    dtrace_errmsg(dtp, dtrace_errno(dtp))));
152 		}
153 
154 		nmatches++;
155 	}
156 
157 	glob = strisglob(pp->dpp_name);
158 	if (!glob && nmatches == 0) {
159 		off = strtoull(pp->dpp_name, &end, 16);
160 		if (*end != '\0') {
161 			return (dt_pid_error(dtp, pcb, dpr, ftp, D_PROC_NAME,
162 			    "'%s' is an invalid probe name", pp->dpp_name));
163 		}
164 
165 		if (off >= symp->st_size) {
166 			return (dt_pid_error(dtp, pcb, dpr, ftp, D_PROC_OFF,
167 			    "offset 0x%llx outside of function '%s'",
168 			    (u_longlong_t)off, func));
169 		}
170 
171 		err = dt_pid_create_offset_probe(pp->dpp_pr, pp->dpp_dtp, ftp,
172 		    symp, off);
173 
174 		if (err == DT_PROC_ERR) {
175 			return (dt_pid_error(dtp, pcb, dpr, ftp,
176 			    D_PROC_CREATEFAIL, "failed to create probe at "
177 			    "'%s+0x%llx': %s", func, (u_longlong_t)off,
178 			    dtrace_errmsg(dtp, dtrace_errno(dtp))));
179 		}
180 
181 		if (err == DT_PROC_ALIGN) {
182 			return (dt_pid_error(dtp, pcb, dpr, ftp, D_PROC_ALIGN,
183 			    "offset 0x%llx is not aligned on an instruction",
184 			    (u_longlong_t)off));
185 		}
186 
187 		nmatches++;
188 
189 	} else if (glob && !isdash) {
190 		if (dt_pid_create_glob_offset_probes(pp->dpp_pr,
191 		    pp->dpp_dtp, ftp, symp, pp->dpp_name) < 0) {
192 			return (dt_pid_error(dtp, pcb, dpr, ftp,
193 			    D_PROC_CREATEFAIL,
194 			    "failed to create offset probes in '%s': %s", func,
195 			    dtrace_errmsg(dtp, dtrace_errno(dtp))));
196 		}
197 
198 		nmatches++;
199 	}
200 
201 	pp->dpp_nmatches += nmatches;
202 
203 	dt_free(dtp, ftp);
204 
205 	return (0);
206 }
207 
208 static int
209 dt_pid_sym_filt(void *arg, const GElf_Sym *symp, const char *func)
210 {
211 	dt_pid_probe_t *pp = arg;
212 
213 	if (symp->st_shndx == SHN_UNDEF)
214 		return (0);
215 
216 	if (symp->st_size == 0) {
217 		dt_dprintf("st_size of %s is zero\n", func);
218 		return (0);
219 	}
220 
221 	if (pp->dpp_last_taken == 0 ||
222 	    symp->st_value != pp->dpp_last.st_value ||
223 	    symp->st_size != pp->dpp_last.st_size) {
224 		/*
225 		 * Due to 4524008, _init and _fini may have a bloated st_size.
226 		 * While this bug has been fixed for a while, old binaries
227 		 * may exist that still exhibit this problem. As a result, we
228 		 * don't match _init and _fini though we allow users to
229 		 * specify them explicitly.
230 		 */
231 		if (strcmp(func, "_init") == 0 || strcmp(func, "_fini") == 0)
232 			return (0);
233 
234 		if ((pp->dpp_last_taken = gmatch(func, pp->dpp_func)) != 0) {
235 			pp->dpp_last = *symp;
236 			return (dt_pid_per_sym(pp, symp, func));
237 		}
238 	}
239 
240 	return (0);
241 }
242 
243 static int
244 dt_pid_per_mod(void *arg, const prmap_t *pmp, const char *obj)
245 {
246 	dt_pid_probe_t *pp = arg;
247 	dtrace_hdl_t *dtp = pp->dpp_dtp;
248 	dt_pcb_t *pcb = pp->dpp_pcb;
249 	dt_proc_t *dpr = pp->dpp_dpr;
250 	GElf_Sym sym;
251 
252 	if (obj == NULL)
253 		return (0);
254 
255 	(void) Plmid(pp->dpp_pr, pmp->pr_vaddr, &pp->dpp_lmid);
256 
257 	if ((pp->dpp_obj = strrchr(obj, '/')) == NULL)
258 		pp->dpp_obj = obj;
259 	else
260 		pp->dpp_obj++;
261 
262 	if (Pxlookup_by_name(pp->dpp_pr, pp->dpp_lmid, obj, ".stret1", &sym,
263 	    NULL) == 0)
264 		pp->dpp_stret[0] = sym.st_value;
265 	else
266 		pp->dpp_stret[0] = 0;
267 
268 	if (Pxlookup_by_name(pp->dpp_pr, pp->dpp_lmid, obj, ".stret2", &sym,
269 	    NULL) == 0)
270 		pp->dpp_stret[1] = sym.st_value;
271 	else
272 		pp->dpp_stret[1] = 0;
273 
274 	if (Pxlookup_by_name(pp->dpp_pr, pp->dpp_lmid, obj, ".stret4", &sym,
275 	    NULL) == 0)
276 		pp->dpp_stret[2] = sym.st_value;
277 	else
278 		pp->dpp_stret[2] = 0;
279 
280 	if (Pxlookup_by_name(pp->dpp_pr, pp->dpp_lmid, obj, ".stret8", &sym,
281 	    NULL) == 0)
282 		pp->dpp_stret[3] = sym.st_value;
283 	else
284 		pp->dpp_stret[3] = 0;
285 
286 	dt_dprintf("%s stret %llx %llx %llx %llx\n", obj,
287 	    (u_longlong_t)pp->dpp_stret[0], (u_longlong_t)pp->dpp_stret[1],
288 	    (u_longlong_t)pp->dpp_stret[2], (u_longlong_t)pp->dpp_stret[3]);
289 
290 	/*
291 	 * If pp->dpp_func contains any globbing meta-characters, we need
292 	 * to iterate over the symbol table and compare each function name
293 	 * against the pattern.
294 	 */
295 	if (!strisglob(pp->dpp_func)) {
296 		/*
297 		 * If we fail to lookup the symbol, try interpreting the
298 		 * function as the special "-" function that indicates that the
299 		 * probe name should be interpreted as a absolute virtual
300 		 * address. If that fails and we were matching a specific
301 		 * function in a specific module, report the error, otherwise
302 		 * just fail silently in the hopes that some other object will
303 		 * contain the desired symbol.
304 		 */
305 		if (Pxlookup_by_name(pp->dpp_pr, pp->dpp_lmid, obj,
306 		    pp->dpp_func, &sym, NULL) != 0) {
307 			if (strcmp("-", pp->dpp_func) == 0) {
308 				sym.st_name = 0;
309 				sym.st_info =
310 				    GELF_ST_INFO(STB_LOCAL, STT_FUNC);
311 				sym.st_other = 0;
312 				sym.st_value = 0;
313 				sym.st_size = Pstatus(pp->dpp_pr)->pr_dmodel ==
314 				    PR_MODEL_ILP32 ? -1U : -1ULL;
315 
316 			} else if (!strisglob(pp->dpp_mod)) {
317 				return (dt_pid_error(dtp, pcb, dpr, NULL,
318 				    D_PROC_FUNC,
319 				    "failed to lookup '%s' in module '%s'",
320 				    pp->dpp_func, pp->dpp_mod));
321 			} else {
322 				return (0);
323 			}
324 		}
325 
326 		/*
327 		 * Only match defined functions of non-zero size.
328 		 */
329 		if (GELF_ST_TYPE(sym.st_info) != STT_FUNC ||
330 		    sym.st_shndx == SHN_UNDEF || sym.st_size == 0)
331 			return (0);
332 
333 		/*
334 		 * We don't instrument PLTs -- they're dynamically rewritten,
335 		 * and, so, inherently dicey to instrument.
336 		 */
337 		if (Ppltdest(pp->dpp_pr, sym.st_value) != NULL)
338 			return (0);
339 
340 		(void) Plookup_by_addr(pp->dpp_pr, sym.st_value, pp->dpp_func,
341 		    DTRACE_FUNCNAMELEN, &sym);
342 
343 		return (dt_pid_per_sym(pp, &sym, pp->dpp_func));
344 	} else {
345 		uint_t nmatches = pp->dpp_nmatches;
346 
347 		if (Psymbol_iter_by_addr(pp->dpp_pr, obj, PR_SYMTAB,
348 		    BIND_ANY | TYPE_FUNC, dt_pid_sym_filt, pp) == 1)
349 			return (1);
350 
351 		if (nmatches == pp->dpp_nmatches) {
352 			/*
353 			 * If we didn't match anything in the PR_SYMTAB, try
354 			 * the PR_DYNSYM.
355 			 */
356 			if (Psymbol_iter_by_addr(pp->dpp_pr, obj, PR_DYNSYM,
357 			    BIND_ANY | TYPE_FUNC, dt_pid_sym_filt, pp) == 1)
358 				return (1);
359 		}
360 	}
361 
362 	return (0);
363 }
364 
365 static int
366 dt_pid_mod_filt(void *arg, const prmap_t *pmp, const char *obj)
367 {
368 	char name[DTRACE_MODNAMELEN];
369 	dt_pid_probe_t *pp = arg;
370 
371 	if ((pp->dpp_obj = strrchr(obj, '/')) == NULL)
372 		pp->dpp_obj = obj;
373 	else
374 		pp->dpp_obj++;
375 
376 	if (gmatch(pp->dpp_obj, pp->dpp_mod))
377 		return (dt_pid_per_mod(pp, pmp, obj));
378 
379 	(void) Plmid(pp->dpp_pr, pmp->pr_vaddr, &pp->dpp_lmid);
380 
381 	dt_pid_objname(name, sizeof (name), pp->dpp_lmid, pp->dpp_obj);
382 
383 	if (gmatch(name, pp->dpp_mod))
384 		return (dt_pid_per_mod(pp, pmp, obj));
385 
386 	return (0);
387 }
388 
389 static const prmap_t *
390 dt_pid_fix_mod(dtrace_probedesc_t *pdp, struct ps_prochandle *P)
391 {
392 	char m[MAXPATHLEN];
393 	Lmid_t lmid = PR_LMID_EVERY;
394 	const char *obj;
395 	const prmap_t *pmp;
396 
397 	/*
398 	 * Pick apart the link map from the library name.
399 	 */
400 	if (strchr(pdp->dtpd_mod, '`') != NULL) {
401 		char *end;
402 
403 		if (strncmp(pdp->dtpd_mod, "LM", 2) != 0 ||
404 		    !isdigit(pdp->dtpd_mod[2]))
405 			return (NULL);
406 
407 		lmid = strtoul(&pdp->dtpd_mod[2], &end, 16);
408 
409 		obj = end + 1;
410 
411 		if (*end != '`' || strchr(obj, '`') != NULL)
412 			return (NULL);
413 
414 	} else {
415 		obj = pdp->dtpd_mod;
416 	}
417 
418 	if ((pmp = Plmid_to_map(P, lmid, obj)) == NULL)
419 		return (NULL);
420 
421 	(void) Pobjname(P, pmp->pr_vaddr, m, sizeof (m));
422 	if ((obj = strrchr(m, '/')) == NULL)
423 		obj = &m[0];
424 	else
425 		obj++;
426 
427 	(void) Plmid(P, pmp->pr_vaddr, &lmid);
428 	dt_pid_objname(pdp->dtpd_mod, sizeof (pdp->dtpd_mod), lmid, obj);
429 
430 	return (pmp);
431 }
432 
433 
434 static int
435 dt_pid_create_pid_probes(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp,
436     dt_pcb_t *pcb, dt_proc_t *dpr)
437 {
438 	dt_pid_probe_t pp;
439 	int ret = 0;
440 
441 	pp.dpp_dtp = dtp;
442 	pp.dpp_dpr = dpr;
443 	pp.dpp_pr = dpr->dpr_proc;
444 	pp.dpp_pcb = pcb;
445 
446 	/*
447 	 * We can only trace dynamically-linked executables (since we've
448 	 * hidden some magic in ld.so.1 as well as libc.so.1).
449 	 */
450 	if (Pname_to_map(pp.dpp_pr, PR_OBJ_LDSO) == NULL) {
451 		return (dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_DYN,
452 		    "process %s is not a dynamically-linked executable",
453 		    &pdp->dtpd_provider[3]));
454 	}
455 
456 	pp.dpp_mod = pdp->dtpd_mod[0] != '\0' ? pdp->dtpd_mod : "*";
457 	pp.dpp_func = pdp->dtpd_func[0] != '\0' ? pdp->dtpd_func : "*";
458 	pp.dpp_name = pdp->dtpd_name[0] != '\0' ? pdp->dtpd_name : "*";
459 	pp.dpp_last_taken = 0;
460 
461 	if (strcmp(pp.dpp_func, "-") == 0) {
462 		const prmap_t *aout, *pmp;
463 
464 		if (pdp->dtpd_mod[0] == '\0') {
465 			pp.dpp_mod = pdp->dtpd_mod;
466 			(void) strcpy(pdp->dtpd_mod, "a.out");
467 		} else if (strisglob(pp.dpp_mod) ||
468 		    (aout = Pname_to_map(pp.dpp_pr, "a.out")) == NULL ||
469 		    (pmp = Pname_to_map(pp.dpp_pr, pp.dpp_mod)) == NULL ||
470 		    aout->pr_vaddr != pmp->pr_vaddr) {
471 			return (dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_LIB,
472 			    "only the a.out module is valid with the "
473 			    "'-' function"));
474 		}
475 
476 		if (strisglob(pp.dpp_name)) {
477 			return (dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_NAME,
478 			    "only individual addresses may be specified "
479 			    "with the '-' function"));
480 		}
481 	}
482 
483 	/*
484 	 * If pp.dpp_mod contains any globbing meta-characters, we need
485 	 * to iterate over each module and compare its name against the
486 	 * pattern. An empty module name is treated as '*'.
487 	 */
488 	if (strisglob(pp.dpp_mod)) {
489 		ret = Pobject_iter(pp.dpp_pr, dt_pid_mod_filt, &pp);
490 	} else {
491 		const prmap_t *pmp;
492 		char *obj;
493 
494 		/*
495 		 * If we can't find a matching module, don't sweat it -- either
496 		 * we'll fail the enabling because the probes don't exist or
497 		 * we'll wait for that module to come along.
498 		 */
499 		if ((pmp = dt_pid_fix_mod(pdp, pp.dpp_pr)) != NULL) {
500 			if ((obj = strchr(pdp->dtpd_mod, '`')) == NULL)
501 				obj = pdp->dtpd_mod;
502 			else
503 				obj++;
504 
505 			ret = dt_pid_per_mod(&pp, pmp, obj);
506 		}
507 	}
508 
509 	return (ret);
510 }
511 
512 static int
513 dt_pid_usdt_mapping(void *data, const prmap_t *pmp, const char *oname)
514 {
515 	struct ps_prochandle *P = data;
516 	GElf_Sym sym;
517 	prsyminfo_t sip;
518 	dof_helper_t dh;
519 	GElf_Half e_type;
520 	const char *mname;
521 	const char *syms[] = { "___SUNW_dof", "__SUNW_dof" };
522 	int i, fd = -1;
523 
524 	/*
525 	 * The symbol ___SUNW_dof is for lazy-loaded DOF sections, and
526 	 * __SUNW_dof is for actively-loaded DOF sections. We try to force
527 	 * in both types of DOF section since the process may not yet have
528 	 * run the code to instantiate these providers.
529 	 */
530 	for (i = 0; i < 2; i++) {
531 		if (Pxlookup_by_name(P, PR_LMID_EVERY, oname, syms[i], &sym,
532 		    &sip) != 0) {
533 			continue;
534 		}
535 
536 		if ((mname = strrchr(oname, '/')) == NULL)
537 			mname = oname;
538 		else
539 			mname++;
540 
541 		dt_dprintf("lookup of %s succeeded for %s\n", syms[i], mname);
542 
543 		if (Pread(P, &e_type, sizeof (e_type), pmp->pr_vaddr +
544 		    offsetof(Elf64_Ehdr, e_type)) != sizeof (e_type)) {
545 			dt_dprintf("read of ELF header failed");
546 			continue;
547 		}
548 
549 		dh.dofhp_dof = sym.st_value;
550 		dh.dofhp_addr = (e_type == ET_EXEC) ? 0 : pmp->pr_vaddr;
551 
552 		dt_pid_objname(dh.dofhp_mod, sizeof (dh.dofhp_mod),
553 		    sip.prs_lmid, mname);
554 
555 		if (fd == -1 &&
556 		    (fd = pr_open(P, "/dev/dtrace/helper", O_RDWR, 0)) < 0) {
557 			dt_dprintf("pr_open of helper device failed: %s\n",
558 			    strerror(errno));
559 			return (-1); /* errno is set for us */
560 		}
561 
562 		if (pr_ioctl(P, fd, DTRACEHIOC_ADDDOF, &dh, sizeof (dh)) < 0)
563 			dt_dprintf("DOF was rejected for %s\n", dh.dofhp_mod);
564 	}
565 
566 	if (fd != -1)
567 		(void) pr_close(P, fd);
568 
569 	return (0);
570 }
571 
572 static int
573 dt_pid_create_usdt_probes(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp,
574     dt_pcb_t *pcb, dt_proc_t *dpr)
575 {
576 	struct ps_prochandle *P = dpr->dpr_proc;
577 	int ret = 0;
578 
579 	assert(DT_MUTEX_HELD(&dpr->dpr_lock));
580 
581 	(void) Pupdate_maps(P);
582 	if (Pobject_iter(P, dt_pid_usdt_mapping, P) != 0) {
583 		ret = -1;
584 		(void) dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_USDT,
585 		    "failed to instantiate probes for pid %d: %s",
586 		    (int)Pstatus(P)->pr_pid, strerror(errno));
587 	}
588 
589 	/*
590 	 * Put the module name in its canonical form.
591 	 */
592 	(void) dt_pid_fix_mod(pdp, P);
593 
594 	return (ret);
595 }
596 
597 static pid_t
598 dt_pid_get_pid(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp, dt_pcb_t *pcb,
599     dt_proc_t *dpr)
600 {
601 	pid_t pid;
602 	char *c, *last = NULL, *end;
603 
604 	for (c = &pdp->dtpd_provider[0]; *c != '\0'; c++) {
605 		if (!isdigit(*c))
606 			last = c;
607 	}
608 
609 	if (last == NULL || (*(++last) == '\0')) {
610 		(void) dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_BADPROV,
611 		    "'%s' is not a valid provider", pdp->dtpd_provider);
612 		return (-1);
613 	}
614 
615 	errno = 0;
616 	pid = strtol(last, &end, 10);
617 
618 	if (errno != 0 || end == last || end[0] != '\0' || pid <= 0) {
619 		(void) dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_BADPID,
620 		    "'%s' does not contain a valid pid", pdp->dtpd_provider);
621 		return (-1);
622 	}
623 
624 	return (pid);
625 }
626 
627 int
628 dt_pid_create_probes(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp, dt_pcb_t *pcb)
629 {
630 	char provname[DTRACE_PROVNAMELEN];
631 	struct ps_prochandle *P;
632 	dt_proc_t *dpr;
633 	pid_t pid;
634 	int err = 0;
635 
636 	assert(pcb != NULL);
637 
638 	if ((pid = dt_pid_get_pid(pdp, dtp, pcb, NULL)) == -1)
639 		return (-1);
640 
641 	if (dtp->dt_ftfd == -1) {
642 		if (dtp->dt_fterr == ENOENT) {
643 			(void) dt_pid_error(dtp, pcb, NULL, NULL, D_PROC_NODEV,
644 			    "pid provider is not installed on this system");
645 		} else {
646 			(void) dt_pid_error(dtp, pcb, NULL, NULL, D_PROC_NODEV,
647 			    "pid provider is not available: %s",
648 			    strerror(dtp->dt_fterr));
649 		}
650 
651 		return (-1);
652 	}
653 
654 	(void) snprintf(provname, sizeof (provname), "pid%d", (int)pid);
655 
656 	if (gmatch(provname, pdp->dtpd_provider) != 0) {
657 		if ((P = dt_proc_grab(dtp, pid, PGRAB_RDONLY | PGRAB_FORCE,
658 		    0)) == NULL) {
659 			(void) dt_pid_error(dtp, pcb, NULL, NULL, D_PROC_GRAB,
660 			    "failed to grab process %d", (int)pid);
661 			return (-1);
662 		}
663 
664 		dpr = dt_proc_lookup(dtp, P, 0);
665 		assert(dpr != NULL);
666 		(void) pthread_mutex_lock(&dpr->dpr_lock);
667 
668 		if ((err = dt_pid_create_pid_probes(pdp, dtp, pcb, dpr)) == 0) {
669 			/*
670 			 * Alert other retained enablings which may match
671 			 * against the newly created probes.
672 			 */
673 			(void) dt_ioctl(dtp, DTRACEIOC_ENABLE, NULL);
674 		}
675 
676 		(void) pthread_mutex_unlock(&dpr->dpr_lock);
677 		dt_proc_release(dtp, P);
678 	}
679 
680 	/*
681 	 * If it's not strictly a pid provider, we might match a USDT provider.
682 	 */
683 	if (strcmp(provname, pdp->dtpd_provider) != 0) {
684 		if ((P = dt_proc_grab(dtp, pid, 0, 1)) == NULL) {
685 			(void) dt_pid_error(dtp, pcb, NULL, NULL, D_PROC_GRAB,
686 			    "failed to grab process %d", (int)pid);
687 			return (-1);
688 		}
689 
690 		dpr = dt_proc_lookup(dtp, P, 0);
691 		assert(dpr != NULL);
692 		(void) pthread_mutex_lock(&dpr->dpr_lock);
693 
694 		if (!dpr->dpr_usdt) {
695 			err = dt_pid_create_usdt_probes(pdp, dtp, pcb, dpr);
696 			dpr->dpr_usdt = B_TRUE;
697 		}
698 
699 		(void) pthread_mutex_unlock(&dpr->dpr_lock);
700 		dt_proc_release(dtp, P);
701 	}
702 
703 	return (err ? -1 : 0);
704 }
705 
706 int
707 dt_pid_create_probes_module(dtrace_hdl_t *dtp, dt_proc_t *dpr)
708 {
709 	dtrace_prog_t *pgp;
710 	dt_stmt_t *stp;
711 	dtrace_probedesc_t *pdp, pd;
712 	pid_t pid;
713 	int ret = 0, found = B_FALSE;
714 	char provname[DTRACE_PROVNAMELEN];
715 
716 	(void) snprintf(provname, sizeof (provname), "pid%d",
717 	    (int)dpr->dpr_pid);
718 
719 	for (pgp = dt_list_next(&dtp->dt_programs); pgp != NULL;
720 	    pgp = dt_list_next(pgp)) {
721 
722 		for (stp = dt_list_next(&pgp->dp_stmts); stp != NULL;
723 		    stp = dt_list_next(stp)) {
724 
725 			pdp = &stp->ds_desc->dtsd_ecbdesc->dted_probe;
726 			pid = dt_pid_get_pid(pdp, dtp, NULL, dpr);
727 			if (pid != dpr->dpr_pid)
728 				continue;
729 
730 			found = B_TRUE;
731 
732 			pd = *pdp;
733 
734 			if (gmatch(provname, pdp->dtpd_provider) != 0 &&
735 			    dt_pid_create_pid_probes(&pd, dtp, NULL, dpr) != 0)
736 				ret = 1;
737 
738 			/*
739 			 * If it's not strictly a pid provider, we might match
740 			 * a USDT provider.
741 			 */
742 			if (strcmp(provname, pdp->dtpd_provider) != 0 &&
743 			    dt_pid_create_usdt_probes(&pd, dtp, NULL, dpr) != 0)
744 				ret = 1;
745 		}
746 	}
747 
748 	if (found) {
749 		/*
750 		 * Give DTrace a shot to the ribs to get it to check
751 		 * out the newly created probes.
752 		 */
753 		(void) dt_ioctl(dtp, DTRACEIOC_ENABLE, NULL);
754 	}
755 
756 	return (ret);
757 }
758