dt_open.c

来自「Sun Solaris 10 中的 DTrace 组件的源代码。请参看: htt」· C语言 代码 · 共 1,315 行 · 第 1/4 页

    const dtrace_vector_t *vector, void *arg)
{
	dtrace_hdl_t *dtp = NULL;
	int dtfd = -1, ftfd = -1, fterr = 0;
	dtrace_prog_t *pgp;
	dt_module_t *dmp;
	dt_provmod_t *provmod = NULL;
	int i, err;

	const dt_intrinsic_t *dinp;
	const dt_typedef_t *dtyp;
	const dt_ident_t *idp;

	dtrace_typeinfo_t dtt;
	ctf_funcinfo_t ctc;
	ctf_arinfo_t ctr;

	dt_fdlist_t df = { NULL, 0, 0 };
	char *p, *q, *path = NULL;
	const char *isadir = NULL;
	int pathlen;

	char isadef[32], utsdef[32];
	char s1[64], s2[64];

	if (version <= 0)
		return (set_open_errno(dtp, errp, EINVAL));

	if (version > DTRACE_VERSION)
		return (set_open_errno(dtp, errp, EDT_VERSION));

	if (flags & ~DTRACE_O_MASK)
		return (set_open_errno(dtp, errp, EINVAL));

	if ((flags & DTRACE_O_LP64) && (flags & DTRACE_O_ILP32))
		return (set_open_errno(dtp, errp, EINVAL));

	if (vector == NULL && arg != NULL)
		return (set_open_errno(dtp, errp, EINVAL));

	if (elf_version(EV_CURRENT) == EV_NONE)
		return (set_open_errno(dtp, errp, EDT_ELFVERSION));

	if (vector != NULL || (flags & DTRACE_O_NODEV))
		goto alloc; /* do not attempt to open dtrace device */

	/*
	 * For each directory in the kernel's module path, build the name of
	 * the corresponding dtrace provider subdirectory and attempt to open a
	 * pseudo-driver whose name matches the name of each provider therein.
	 * We hold them open in the df.df_fds list until we open the DTrace
	 * driver itself, allowing us to see all of the probes provided on this
	 * system.  Once we have the DTrace driver open, we can safely close
	 * all the providers now that they have registered with the framework.
	 */
	if (sysinfo(SI_ISALIST, isadef, sizeof (isadef)) > 0) {
		if (strstr(isadef, "sparcv9") != NULL)
			isadir = "sparcv9";
		else if (strstr(isadef, "amd64") != NULL)
			isadir = "amd64";
	}

	if (modctl(MODGETPATHLEN, NULL, &pathlen) == 0 &&
	    (path = malloc(pathlen + 1)) != NULL &&
	    modctl(MODGETPATH, NULL, path) == 0) {
		for (p = path; *p != '\0'; p = q) {
			if ((q = strchr(p, ' ')) != NULL)
				*q++ = '\0';
			else
				q = p + strlen(p);
			dt_provmod_open(&provmod, &df, p,
			    _dtrace_moddir, isadir);
		}
	}

	dtfd = open("/devices/pseudo/dtrace@0:dtrace", O_RDWR);
	err = errno; /* save errno from opening dtfd */

	ftfd = open("/devices/pseudo/fasttrap@0:fasttrap", O_RDWR);
	fterr = ftfd == -1 ? errno : 0; /* save errno from open ftfd */

	while (df.df_ents-- != 0)
		(void) close(df.df_fds[df.df_ents]);

	free(df.df_fds);
	free(path);

	/*
	 * If we failed to open the dtrace device, fail dtrace_open().
	 * We convert some kernel errnos to custom libdtrace errnos to
	 * improve the resulting message from the usual strerror().
	 */
	if (dtfd == -1) {
		dt_provmod_destroy(&provmod);
		switch (err) {
		case ENOENT:
			if (getzoneid() != GLOBAL_ZONEID)
				err = EDT_ZNOENT;
			else
				err = EDT_GNOENT;
			break;
		case EBUSY:
			err = EDT_BUSY;
			break;
		case EACCES:
			err = EDT_ACCESS;
			break;
		}
		return (set_open_errno(dtp, errp, err));
	}

	(void) fcntl(dtfd, F_SETFD, FD_CLOEXEC);
	(void) fcntl(ftfd, F_SETFD, FD_CLOEXEC);

alloc:
	if ((dtp = malloc(sizeof (dtrace_hdl_t))) == NULL)
		return (set_open_errno(dtp, errp, EDT_NOMEM));

	bzero(dtp, sizeof (dtrace_hdl_t));
	dtp->dt_oflags = flags;
	dtp->dt_prcmode = DT_PROC_STOP_PREINIT;
	dtp->dt_linkmode = DT_LINK_KERNEL;
	dtp->dt_stdcmode = DT_STDC_XA;
	dtp->dt_version = version;
	dtp->dt_fd = dtfd;
	dtp->dt_ftfd = ftfd;
	dtp->dt_fterr = fterr;
	dtp->dt_cdefs_fd = -1;
	dtp->dt_ddefs_fd = -1;
	dtp->dt_modbuckets = _dtrace_strbuckets;
	dtp->dt_mods = calloc(dtp->dt_modbuckets, sizeof (dt_module_t *));
	dtp->dt_provbuckets = _dtrace_strbuckets;
	dtp->dt_provs = calloc(dtp->dt_provbuckets, sizeof (dt_provider_t *));
	dt_proc_hash_create(dtp);
	dtp->dt_vmax = DT_VERS_LATEST;
	dtp->dt_cpp_path = strdup(_dtrace_defcpp);
	dtp->dt_cpp_argv = malloc(sizeof (char *));
	dtp->dt_cpp_argc = 1;
	dtp->dt_cpp_args = 1;
	dtp->dt_ld_path = strdup(_dtrace_defld);
	dtp->dt_provmod = provmod;
	dtp->dt_vector = vector;
	dtp->dt_varg = arg;

	if (dtp->dt_mods == NULL || dtp->dt_provs == NULL ||
	    dtp->dt_procs == NULL || dtp->dt_ld_path == NULL ||
	    dtp->dt_cpp_path == NULL || dtp->dt_cpp_argv == NULL)
		return (set_open_errno(dtp, errp, EDT_NOMEM));

	for (i = 0; i < DTRACEOPT_MAX; i++)
		dtp->dt_options[i] = DTRACEOPT_UNSET;

	dtp->dt_cpp_argv[0] = (char *)strbasename(dtp->dt_cpp_path);

	(void) snprintf(isadef, sizeof (isadef), "-D__SUNW_D_%u",
	    (uint_t)(sizeof (void *) * NBBY));

	(void) snprintf(utsdef, sizeof (utsdef), "-D__%s_%s",
	    dt_get_sysinfo(SI_SYSNAME, s1, sizeof (s1)),
	    dt_get_sysinfo(SI_RELEASE, s2, sizeof (s2)));

	if (dt_cpp_add_arg(dtp, "-D__sun") == NULL ||
	    dt_cpp_add_arg(dtp, "-D__unix") == NULL ||
	    dt_cpp_add_arg(dtp, "-D__SVR4") == NULL ||
	    dt_cpp_add_arg(dtp, "-D__SUNW_D=1") == NULL ||
	    dt_cpp_add_arg(dtp, isadef) == NULL ||
	    dt_cpp_add_arg(dtp, utsdef) == NULL)
		return (set_open_errno(dtp, errp, EDT_NOMEM));

	if (flags & DTRACE_O_NODEV)
		bcopy(&_dtrace_conf, &dtp->dt_conf, sizeof (_dtrace_conf));
	else if (dt_ioctl(dtp, DTRACEIOC_CONF, &dtp->dt_conf) != 0)
		return (set_open_errno(dtp, errp, errno));

	if (flags & DTRACE_O_LP64)
		dtp->dt_conf.dtc_ctfmodel = CTF_MODEL_LP64;
	else if (flags & DTRACE_O_ILP32)
		dtp->dt_conf.dtc_ctfmodel = CTF_MODEL_ILP32;

#ifdef __sparc
	/*
	 * On SPARC systems, __sparc is always defined for <sys/isa_defs.h>
	 * and __sparcv9 is defined if we are doing a 64-bit compile.
	 */
	if (dt_cpp_add_arg(dtp, "-D__sparc") == NULL)
		return (set_open_errno(dtp, errp, EDT_NOMEM));

	if (dtp->dt_conf.dtc_ctfmodel == CTF_MODEL_LP64 &&
	    dt_cpp_add_arg(dtp, "-D__sparcv9") == NULL)
		return (set_open_errno(dtp, errp, EDT_NOMEM));
#endif

#ifdef __x86
	/*
	 * On x86 systems, __i386 is defined for <sys/isa_defs.h> for 32-bit
	 * compiles and __amd64 is defined for 64-bit compiles.  Unlike SPARC,
	 * they are defined exclusive of one another (see PSARC 2004/619).
	 */
	if (dtp->dt_conf.dtc_ctfmodel == CTF_MODEL_LP64)
		p = dt_cpp_add_arg(dtp, "-D__amd64");
	else
		p = dt_cpp_add_arg(dtp, "-D__i386");

	if (p == NULL)
		return (set_open_errno(dtp, errp, EDT_NOMEM));
#endif

	if (dtp->dt_conf.dtc_difversion < DIF_VERSION)
		return (set_open_errno(dtp, errp, EDT_DIFVERS));

	if (dtp->dt_conf.dtc_ctfmodel == CTF_MODEL_ILP32)
		bcopy(_dtrace_ints_32, dtp->dt_ints, sizeof (_dtrace_ints_32));
	else
		bcopy(_dtrace_ints_64, dtp->dt_ints, sizeof (_dtrace_ints_64));

	dtp->dt_macros = dt_idhash_create("macro", NULL, 0, UINT_MAX);
	dtp->dt_aggs = dt_idhash_create("aggregation", NULL, 0, UINT_MAX);

	dtp->dt_globals = dt_idhash_create("global", _dtrace_globals,
	    DIF_VAR_OTHER_UBASE, DIF_VAR_OTHER_MAX);

	dtp->dt_tls = dt_idhash_create("thread local", NULL,
	    DIF_VAR_OTHER_UBASE, DIF_VAR_OTHER_MAX);

	if (dtp->dt_macros == NULL || dtp->dt_aggs == NULL ||
	    dtp->dt_globals == NULL || dtp->dt_tls == NULL)
		return (set_open_errno(dtp, errp, EDT_NOMEM));

	/*
	 * Populate the dt_macros identifier hash table by hand: we can't use
	 * the dt_idhash_populate() mechanism because we're not yet compiling
	 * and dtrace_update() needs to immediately reference these idents.
	 */
	for (idp = _dtrace_macros; idp->di_name != NULL; idp++) {
		if (dt_idhash_insert(dtp->dt_macros, idp->di_name,
		    idp->di_kind, idp->di_flags, idp->di_id, idp->di_attr,
		    idp->di_vers, idp->di_ops ? idp->di_ops : &dt_idops_thaw,
		    idp->di_iarg, 0) == NULL)
			return (set_open_errno(dtp, errp, EDT_NOMEM));
	}

	/*
	 * Update the module list using /system/object and load the values for
	 * the macro variable definitions according to the current process.
	 */
	dtrace_update(dtp);

	/*
	 * Select the intrinsics and typedefs we want based on the data model.
	 * The intrinsics are under "C".  The typedefs are added under "D".
	 */
	if (dtp->dt_conf.dtc_ctfmodel == CTF_MODEL_ILP32) {
		dinp = _dtrace_intrinsics_32;
		dtyp = _dtrace_typedefs_32;
	} else {
		dinp = _dtrace_intrinsics_64;
		dtyp = _dtrace_typedefs_64;
	}

	/*
	 * Create a dynamic CTF container under the "C" scope for intrinsic
	 * types and types defined in ANSI-C header files that are included.
	 */
	if ((dmp = dtp->dt_cdefs = dt_module_create(dtp, "C")) == NULL)
		return (set_open_errno(dtp, errp, EDT_NOMEM));

	if ((dmp->dm_ctfp = ctf_create(&dtp->dt_ctferr)) == NULL)
		return (set_open_errno(dtp, errp, EDT_CTF));

	dt_dprintf("created CTF container for %s (%p)\n",
	    dmp->dm_name, (void *)dmp->dm_ctfp);

	(void) ctf_setmodel(dmp->dm_ctfp, dtp->dt_conf.dtc_ctfmodel);

	dmp->dm_flags = DT_DM_LOADED; /* fake up loaded bit */
	dmp->dm_modid = -1; /* no module ID */

	/*
	 * Fill the dynamic "C" CTF container with all of the intrinsic
	 * integer and floating-point types appropriate for this data model.
	 */
	for (; dinp->din_name != NULL; dinp++) {
		if (dinp->din_kind == CTF_K_INTEGER) {
			err = ctf_add_integer(dmp->dm_ctfp, CTF_ADD_ROOT,
			    dinp->din_name, &dinp->din_data);
		} else {
			err = ctf_add_float(dmp->dm_ctfp, CTF_ADD_ROOT,
			    dinp->din_name, &dinp->din_data);
		}

		if (err == CTF_ERR) {
			dt_dprintf("failed to add %s to C container: %s\n",
			    dinp->din_name, ctf_errmsg(
			    ctf_errno(dmp->dm_ctfp)));
			return (set_open_errno(dtp, errp, EDT_CTF));
		}
	}

	if (ctf_update(dmp->dm_ctfp) != 0) {
		dt_dprintf("failed to update C container: %s\n",
		    ctf_errmsg(ctf_errno(dmp->dm_ctfp)));
		return (set_open_errno(dtp, errp, EDT_CTF));
	}

	/*
	 * Add intrinsic pointer types that are needed to initialize printf
	 * format dictionary types (see table in dt_printf.c).
	 */
	(void) ctf_add_pointer(dmp->dm_ctfp, CTF_ADD_ROOT,
	    ctf_lookup_by_name(dmp->dm_ctfp, "void"));

	(void) ctf_add_pointer(dmp->dm_ctfp, CTF_ADD_ROOT,
	    ctf_lookup_by_name(dmp->dm_ctfp, "char"));

	(void) ctf_add_pointer(dmp->dm_ctfp, CTF_ADD_ROOT,
	    ctf_lookup_by_name(dmp->dm_ctfp, "int"));

	if (ctf_update(dmp->dm_ctfp) != 0) {
		dt_dprintf("failed to update C container: %s\n",
		    ctf_errmsg(ctf_errno(dmp->dm_ctfp)));
		return (set_open_errno(dtp, errp, EDT_CTF));
	}

	/*
	 * Create a dynamic CTF container under the "D" scope for types that
	 * are defined by the D program itself or on-the-fly by the D compiler.
	 * The "D" CTF container is a child of the "C" CTF container.
	 */
	if ((dmp = dtp->dt_ddefs = dt_module_create(dtp, "D")) == NULL)