Add libdtrace support for tracing userland programs.

Summary of changes:
* Implement a compatibility shim between Solaris libproc and our
libproc and remove several ifdefs because of this.
* Port the drti to FreeBSD.
* Implement the missing DOODAD sections
* Link with libproc and librtld_db
* Support for ustack, jstack and uregs (by sson@)
* Misc bugfixing

When writing the SUWN_dof section, we had to resort to building the ELF
file layout by "hand". This is the job of libelf, but our libelf doesn't
support this yet. When libelf is fixed, we can remove the code under
#ifdef BROKEN_LIBELF.

Sponsored by:	The FreeBSD Foundation

1 files changed, 21 insertions, 62 deletions

diff --git a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_pid.c b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_pid.c
index a754d9c..52b0eb9 100644
--- a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_pid.c
+++ b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_pid.c
@@ -40,6 +40,9 @@
 #include <dt_program.h>
 #include <dt_pid.h>
 #include <dt_string.h>
+#if !defined(sun)
+#include <libproc_compat.h>
+#endif
 
 typedef struct dt_pid_probe {
 	dtrace_hdl_t *dpp_dtp;
@@ -142,7 +145,6 @@ dt_pid_per_sym(dt_pid_probe_t *pp, const GElf_Sym *symp, const char *func)
 	    pp->dpp_obj);
 
 	if (!isdash && gmatch("return", pp->dpp_name)) {
-#ifdef DOODAD
 		if (dt_pid_create_return_probe(pp->dpp_pr, dtp, ftp, symp,
 		    pp->dpp_stret) < 0) {
 			return (dt_pid_error(dtp, pcb, dpr, ftp,
@@ -150,20 +152,17 @@ dt_pid_per_sym(dt_pid_probe_t *pp, const GElf_Sym *symp, const char *func)
 			    "for '%s': %s", func,
 			    dtrace_errmsg(dtp, dtrace_errno(dtp))));
 		}
-#endif
 
 		nmatches++;
 	}
 
 	if (!isdash && gmatch("entry", pp->dpp_name)) {
-#ifdef DOODAD
 		if (dt_pid_create_entry_probe(pp->dpp_pr, dtp, ftp, symp) < 0) {
 			return (dt_pid_error(dtp, pcb, dpr, ftp,
 			    D_PROC_CREATEFAIL, "failed to create entry probe "
 			    "for '%s': %s", func,
 			    dtrace_errmsg(dtp, dtrace_errno(dtp))));
 		}
-#endif
 
 		nmatches++;
 	}
@@ -182,10 +181,8 @@ dt_pid_per_sym(dt_pid_probe_t *pp, const GElf_Sym *symp, const char *func)
 			    (u_longlong_t)off, func));
 		}
 
-#ifdef DOODAD
 		err = dt_pid_create_offset_probe(pp->dpp_pr, pp->dpp_dtp, ftp,
 		    symp, off);
-#endif
 
 		if (err == DT_PROC_ERR) {
 			return (dt_pid_error(dtp, pcb, dpr, ftp,
@@ -203,7 +200,6 @@ dt_pid_per_sym(dt_pid_probe_t *pp, const GElf_Sym *symp, const char *func)
 		nmatches++;
 
 	} else if (glob && !isdash) {
-#ifdef DOODAD
 		if (dt_pid_create_glob_offset_probes(pp->dpp_pr,
 		    pp->dpp_dtp, ftp, symp, pp->dpp_name) < 0) {
 			return (dt_pid_error(dtp, pcb, dpr, ftp,
@@ -211,7 +207,6 @@ dt_pid_per_sym(dt_pid_probe_t *pp, const GElf_Sym *symp, const char *func)
 			    "failed to create offset probes in '%s': %s", func,
 			    dtrace_errmsg(dtp, dtrace_errno(dtp))));
 		}
-#endif
 
 		nmatches++;
 	}
@@ -279,7 +274,6 @@ dt_pid_per_mod(void *arg, const prmap_t *pmp, const char *obj)
 		pp->dpp_obj = obj;
 	else
 		pp->dpp_obj++;
-
 #if defined(sun)
 	if (Pxlookup_by_name(pp->dpp_pr, pp->dpp_lmid, obj, ".stret1", &sym,
 	    NULL) == 0)
@@ -305,25 +299,10 @@ dt_pid_per_mod(void *arg, const prmap_t *pmp, const char *obj)
 	else
 		pp->dpp_stret[3] = 0;
 #else
-	if (proc_name2sym(pp->dpp_pr, obj, ".stret1", &sym) == 0)
-		pp->dpp_stret[0] = sym.st_value;
-	else
-		pp->dpp_stret[0] = 0;
-
-	if (proc_name2sym(pp->dpp_pr, obj, ".stret2", &sym) == 0)
-		pp->dpp_stret[1] = sym.st_value;
-	else
-		pp->dpp_stret[1] = 0;
-
-	if (proc_name2sym(pp->dpp_pr, obj, ".stret4", &sym) == 0)
-		pp->dpp_stret[2] = sym.st_value;
-	else
-		pp->dpp_stret[2] = 0;
-
-	if (proc_name2sym(pp->dpp_pr, obj, ".stret8", &sym) == 0)
-		pp->dpp_stret[3] = sym.st_value;
-	else
-		pp->dpp_stret[3] = 0;
+	pp->dpp_stret[0] = 0;
+	pp->dpp_stret[1] = 0;
+	pp->dpp_stret[2] = 0;
+	pp->dpp_stret[3] = 0;
 #endif
 
 	dt_dprintf("%s stret %llx %llx %llx %llx\n", obj,
@@ -345,12 +324,8 @@ dt_pid_per_mod(void *arg, const prmap_t *pmp, const char *obj)
 		 * just fail silently in the hopes that some other object will
 		 * contain the desired symbol.
 		 */
-#if defined(sun)
 		if (Pxlookup_by_name(pp->dpp_pr, pp->dpp_lmid, obj,
 		    pp->dpp_func, &sym, NULL) != 0) {
-#else
-		if (proc_name2sym(pp->dpp_pr, obj, pp->dpp_func, &sym) != 0) {
-#endif
 			if (strcmp("-", pp->dpp_func) == 0) {
 				sym.st_name = 0;
 				sym.st_info =
@@ -390,16 +365,11 @@ dt_pid_per_mod(void *arg, const prmap_t *pmp, const char *obj)
 			return (0);
 #endif
 
-#if defined(sun)
 		(void) Plookup_by_addr(pp->dpp_pr, sym.st_value, pp->dpp_func,
-#else
-		(void) proc_addr2sym(pp->dpp_pr, sym.st_value, pp->dpp_func,
-#endif
 		    DTRACE_FUNCNAMELEN, &sym);
 
 		return (dt_pid_per_sym(pp, &sym, pp->dpp_func));
 	} else {
-#ifdef DOODAD
 		uint_t nmatches = pp->dpp_nmatches;
 
 		if (Psymbol_iter_by_addr(pp->dpp_pr, obj, PR_SYMTAB,
@@ -415,7 +385,6 @@ dt_pid_per_mod(void *arg, const prmap_t *pmp, const char *obj)
 			    BIND_ANY | TYPE_FUNC, dt_pid_sym_filt, pp) == 1)
 				return (1);
 		}
-#endif
 	}
 
 	return (0);
@@ -459,14 +428,16 @@ dt_pid_mod_filt(void *arg, const prmap_t *pmp, const char *obj)
 static const prmap_t *
 dt_pid_fix_mod(dtrace_probedesc_t *pdp, struct ps_prochandle *P)
 {
-#ifdef DOODAD
 	char m[MAXPATHLEN];
+#if defined(sun)
 	Lmid_t lmid = PR_LMID_EVERY;
-	const char *obj;
+#else
+	Lmid_t lmid = 0;
 #endif
+	const char *obj;
 	const prmap_t *pmp;
 
-#ifdef DOODAD
+#if defined(sun)
 	/*
 	 * Pick apart the link map from the library name.
 	 */
@@ -487,10 +458,14 @@ dt_pid_fix_mod(dtrace_probedesc_t *pdp, struct ps_prochandle *P)
 	} else {
 		obj = pdp->dtpd_mod;
 	}
+#else
+	obj = pdp->dtpd_mod;
+#endif
 
 	if ((pmp = Plmid_to_map(P, lmid, obj)) == NULL)
 		return (NULL);
 
+#if defined(sun)
 	(void) Pobjname(P, pmp->pr_vaddr, m, sizeof (m));
 	if ((obj = strrchr(m, '/')) == NULL)
 		obj = &m[0];
@@ -498,11 +473,9 @@ dt_pid_fix_mod(dtrace_probedesc_t *pdp, struct ps_prochandle *P)
 		obj++;
 
 	(void) Plmid(P, pmp->pr_vaddr, &lmid);
+#endif
 
 	dt_pid_objname(pdp->dtpd_mod, sizeof (pdp->dtpd_mod), lmid, obj);
-#else
-pmp = NULL;
-#endif
 
 	return (pmp);
 }
@@ -544,13 +517,8 @@ dt_pid_create_pid_probes(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp,
 			pp.dpp_mod = pdp->dtpd_mod;
 			(void) strcpy(pdp->dtpd_mod, "a.out");
 		} else if (strisglob(pp.dpp_mod) ||
-#if defined(sun)
 		    (aout = Pname_to_map(pp.dpp_pr, "a.out")) == NULL ||
 		    (pmp = Pname_to_map(pp.dpp_pr, pp.dpp_mod)) == NULL ||
-#else
-		    (aout = proc_name2map(pp.dpp_pr, "a.out")) == NULL ||
-		    (pmp = proc_name2map(pp.dpp_pr, pp.dpp_mod)) == NULL ||
-#endif
 		    aout->pr_vaddr != pmp->pr_vaddr) {
 			return (dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_LIB,
 			    "only the a.out module is valid with the "
@@ -569,7 +537,6 @@ dt_pid_create_pid_probes(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp,
 	 * to iterate over each module and compare its name against the
 	 * pattern. An empty module name is treated as '*'.
 	 */
-#ifdef DOODAD
 	if (strisglob(pp.dpp_mod)) {
 		ret = Pobject_iter(pp.dpp_pr, dt_pid_mod_filt, &pp);
 	} else {
@@ -590,7 +557,6 @@ dt_pid_create_pid_probes(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp,
 			ret = dt_pid_per_mod(&pp, pmp, obj);
 		}
 	}
-#endif
 
 	return (ret);
 }
@@ -616,12 +582,8 @@ dt_pid_usdt_mapping(void *data, const prmap_t *pmp, const char *oname)
 	 * run the code to instantiate these providers.
 	 */
 	for (i = 0; i < 2; i++) {
-#if defined(sun)
 		if (Pxlookup_by_name(P, PR_LMID_EVERY, oname, syms[i], &sym,
 		    &sip) != 0) {
-#else
-		if (proc_name2sym(P, oname, syms[i], &sym) != 0) {
-#endif
 			continue;
 		}
 
@@ -632,13 +594,11 @@ dt_pid_usdt_mapping(void *data, const prmap_t *pmp, const char *oname)
 
 		dt_dprintf("lookup of %s succeeded for %s\n", syms[i], mname);
 
-#ifdef DOODAD
 		if (Pread(P, &e_type, sizeof (e_type), pmp->pr_vaddr +
 		    offsetof(Elf64_Ehdr, e_type)) != sizeof (e_type)) {
 			dt_dprintf("read of ELF header failed");
 			continue;
 		}
-#endif
 
 		dh.dofhp_dof = sym.st_value;
 		dh.dofhp_addr = (e_type == ET_EXEC) ? 0 : pmp->pr_vaddr;
@@ -650,7 +610,7 @@ dt_pid_usdt_mapping(void *data, const prmap_t *pmp, const char *oname)
 		    0, mname);
 #endif
 
-#ifdef DOODAD
+#if defined(sun)
 		if (fd == -1 &&
 		    (fd = pr_open(P, "/dev/dtrace/helper", O_RDWR, 0)) < 0) {
 			dt_dprintf("pr_open of helper device failed: %s\n",
@@ -663,7 +623,7 @@ dt_pid_usdt_mapping(void *data, const prmap_t *pmp, const char *oname)
 #endif
 	}
 
-#ifdef DOODAD
+#if defined(sun)
 	if (fd != -1)
 		(void) pr_close(P, fd);
 #endif
@@ -679,9 +639,9 @@ dt_pid_create_usdt_probes(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp,
 	int ret = 0;
 
 	assert(DT_MUTEX_HELD(&dpr->dpr_lock));
-
-#ifdef DOODAD
+#if defined(sun)
 	(void) Pupdate_maps(P);
+#endif
 	if (Pobject_iter(P, dt_pid_usdt_mapping, P) != 0) {
 		ret = -1;
 		(void) dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_USDT,
@@ -692,7 +652,6 @@ dt_pid_create_usdt_probes(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp,
 		    (int)proc_getpid(P), strerror(errno));
 #endif
 	}
-#endif
 
 	/*
 	 * Put the module name in its canonical form.