ctf_open.c

Sun Solaris 10 中的 DTrace 组件的源代码。请参看: http://www.sun.com/software/solaris/observability.jsp

	}

	ctf_dprintf("%lu total types processed\n", fp->ctf_typemax);
	ctf_dprintf("%u enum names hashed\n", ctf_hash_size(&fp->ctf_enums));
	ctf_dprintf("%u struct names hashed (%d long)\n",
	    ctf_hash_size(&fp->ctf_structs), nlstructs);
	ctf_dprintf("%u union names hashed (%d long)\n",
	    ctf_hash_size(&fp->ctf_unions), nlunions);
	ctf_dprintf("%u base type names hashed\n",
	    ctf_hash_size(&fp->ctf_names));

	/*
	 * Make an additional pass through the pointer table to find pointers
	 * that point to anonymous typedef nodes.  If we find one, modify the
	 * pointer table so that the pointer is also known to point to the
	 * node that is referenced by the anonymous typedef node.
	 */
	for (id = 1; id <= fp->ctf_typemax; id++) {
		if ((dst = fp->ctf_ptrtab[id]) != 0) {
			tp = LCTF_INDEX_TO_TYPEPTR(fp, id);

			if (LCTF_INFO_KIND(fp, tp->ctt_info) == CTF_K_TYPEDEF &&
			    strcmp(ctf_strptr(fp, tp->ctt_name), "") == 0 &&
			    CTF_TYPE_ISCHILD(tp->ctt_type) == child &&
			    CTF_TYPE_TO_INDEX(tp->ctt_type) <= fp->ctf_typemax)
				fp->ctf_ptrtab[
				    CTF_TYPE_TO_INDEX(tp->ctt_type)] = dst;
		}
	}

	return (0);
}

/*
 * Decode the specified CTF buffer and optional symbol table and create a new
 * CTF container representing the symbolic debugging information.  This code
 * can be used directly by the debugger, or it can be used as the engine for
 * ctf_fdopen() or ctf_open(), below.
 */
ctf_file_t *
ctf_bufopen(const ctf_sect_t *ctfsect, const ctf_sect_t *symsect,
    const ctf_sect_t *strsect, int *errp)
{
	const ctf_preamble_t *pp;
	ctf_header_t hp;
	ctf_file_t *fp;
	void *buf, *base;
	size_t size, hdrsz;
	int err;

	if (ctfsect == NULL || ((symsect == NULL) != (strsect == NULL)))
		return (ctf_set_open_errno(errp, EINVAL));

	if (symsect != NULL && symsect->cts_entsize != sizeof (Elf32_Sym) &&
	    symsect->cts_entsize != sizeof (Elf64_Sym))
		return (ctf_set_open_errno(errp, ECTF_SYMTAB));

	if (symsect != NULL && symsect->cts_data == NULL)
		return (ctf_set_open_errno(errp, ECTF_SYMBAD));

	if (strsect != NULL && strsect->cts_data == NULL)
		return (ctf_set_open_errno(errp, ECTF_STRBAD));

	if (ctfsect->cts_size < sizeof (ctf_preamble_t))
		return (ctf_set_open_errno(errp, ECTF_NOCTFBUF));

	pp = (const ctf_preamble_t *)ctfsect->cts_data;

	ctf_dprintf("ctf_bufopen: magic=0x%x version=%u\n",
	    pp->ctp_magic, pp->ctp_version);

	/*
	 * Validate each part of the CTF header (either V1 or V2).
	 * First, we validate the preamble (common to all versions).  At that
	 * point, we know specific header version, and can validate the
	 * version-specific parts including section offsets and alignments.
	 */
	if (pp->ctp_magic != CTF_MAGIC)
		return (ctf_set_open_errno(errp, ECTF_NOCTFBUF));

	if (pp->ctp_version == CTF_VERSION_2) {
		if (ctfsect->cts_size < sizeof (ctf_header_t))
			return (ctf_set_open_errno(errp, ECTF_NOCTFBUF));

		bcopy(ctfsect->cts_data, &hp, sizeof (hp));
		hdrsz = sizeof (ctf_header_t);

	} else if (pp->ctp_version == CTF_VERSION_1) {
		const ctf_header_v1_t *h1p =
		    (const ctf_header_v1_t *)ctfsect->cts_data;

		if (ctfsect->cts_size < sizeof (ctf_header_v1_t))
			return (ctf_set_open_errno(errp, ECTF_NOCTFBUF));

		bzero(&hp, sizeof (hp));
		hp.cth_preamble = h1p->cth_preamble;
		hp.cth_objtoff = h1p->cth_objtoff;
		hp.cth_funcoff = h1p->cth_funcoff;
		hp.cth_typeoff = h1p->cth_typeoff;
		hp.cth_stroff = h1p->cth_stroff;
		hp.cth_strlen = h1p->cth_strlen;

		hdrsz = sizeof (ctf_header_v1_t);
	} else
		return (ctf_set_open_errno(errp, ECTF_CTFVERS));

	size = hp.cth_stroff + hp.cth_strlen;

	ctf_dprintf("ctf_bufopen: uncompressed size=%lu\n", (ulong_t)size);

	if (hp.cth_lbloff > size || hp.cth_objtoff > size ||
	    hp.cth_funcoff > size || hp.cth_typeoff > size ||
	    hp.cth_stroff > size)
		return (ctf_set_open_errno(errp, ECTF_CORRUPT));

	if (hp.cth_lbloff > hp.cth_objtoff ||
	    hp.cth_objtoff > hp.cth_funcoff ||
	    hp.cth_funcoff > hp.cth_typeoff ||
	    hp.cth_typeoff > hp.cth_stroff)
		return (ctf_set_open_errno(errp, ECTF_CORRUPT));

	if ((hp.cth_lbloff & 3) || (hp.cth_objtoff & 1) ||
	    (hp.cth_funcoff & 1) || (hp.cth_typeoff & 3))
		return (ctf_set_open_errno(errp, ECTF_CORRUPT));

	/*
	 * Once everything is determined to be valid, attempt to decompress
	 * the CTF data buffer if it is compressed.  Otherwise we just put
	 * the data section's buffer pointer into ctf_buf, below.
	 */
	if (hp.cth_flags & CTF_F_COMPRESS) {
		size_t srclen, dstlen;
		const void *src;
		int rc = Z_OK;

		if (ctf_zopen(errp) == NULL)
			return (NULL); /* errp is set for us */

		if ((base = ctf_data_alloc(size + hdrsz)) == MAP_FAILED)
			return (ctf_set_open_errno(errp, ECTF_ZALLOC));

		bcopy(ctfsect->cts_data, base, hdrsz);
		((ctf_preamble_t *)base)->ctp_flags &= ~CTF_F_COMPRESS;
		buf = (uchar_t *)base + hdrsz;

		src = (uchar_t *)ctfsect->cts_data + hdrsz;
		srclen = ctfsect->cts_size - hdrsz;
		dstlen = size;

		if ((rc = z_uncompress(buf, &dstlen, src, srclen)) != Z_OK) {
			ctf_dprintf("zlib inflate err: %s\n", z_strerror(rc));
			ctf_data_free(base, size + hdrsz);
			return (ctf_set_open_errno(errp, ECTF_DECOMPRESS));
		}

		if (dstlen != size) {
			ctf_dprintf("zlib inflate short -- got %lu of %lu "
			    "bytes\n", (ulong_t)dstlen, (ulong_t)size);
			ctf_data_free(base, size + hdrsz);
			return (ctf_set_open_errno(errp, ECTF_CORRUPT));
		}

		ctf_data_protect(base, size + hdrsz);

	} else {
		base = (void *)ctfsect->cts_data;
		buf = (uchar_t *)base + hdrsz;
	}

	/*
	 * Once we have uncompressed and validated the CTF data buffer, we can
	 * proceed with allocating a ctf_file_t and initializing it.
	 */
	if ((fp = ctf_alloc(sizeof (ctf_file_t))) == NULL)
		return (ctf_set_open_errno(errp, EAGAIN));

	bzero(fp, sizeof (ctf_file_t));
	fp->ctf_version = hp.cth_version;
	fp->ctf_fileops = &ctf_fileops[hp.cth_version];
	bcopy(ctfsect, &fp->ctf_data, sizeof (ctf_sect_t));

	if (symsect != NULL) {
		bcopy(symsect, &fp->ctf_symtab, sizeof (ctf_sect_t));
		bcopy(strsect, &fp->ctf_strtab, sizeof (ctf_sect_t));
	}

	if (fp->ctf_data.cts_name != NULL)
		fp->ctf_data.cts_name = ctf_strdup(fp->ctf_data.cts_name);
	if (fp->ctf_symtab.cts_name != NULL)
		fp->ctf_symtab.cts_name = ctf_strdup(fp->ctf_symtab.cts_name);
	if (fp->ctf_strtab.cts_name != NULL)
		fp->ctf_strtab.cts_name = ctf_strdup(fp->ctf_strtab.cts_name);

	if (fp->ctf_data.cts_name == NULL)
		fp->ctf_data.cts_name = _CTF_NULLSTR;
	if (fp->ctf_symtab.cts_name == NULL)
		fp->ctf_symtab.cts_name = _CTF_NULLSTR;
	if (fp->ctf_strtab.cts_name == NULL)
		fp->ctf_strtab.cts_name = _CTF_NULLSTR;

	fp->ctf_str[CTF_STRTAB_0].cts_strs = (const char *)buf + hp.cth_stroff;
	fp->ctf_str[CTF_STRTAB_0].cts_len = hp.cth_strlen;

	if (strsect != NULL) {
		fp->ctf_str[CTF_STRTAB_1].cts_strs = strsect->cts_data;
		fp->ctf_str[CTF_STRTAB_1].cts_len = strsect->cts_size;
	}

	fp->ctf_base = base;
	fp->ctf_buf = buf;
	fp->ctf_size = size + hdrsz;

	/*
	 * If we have a parent container name and label, store the relocated
	 * string pointers in the CTF container for easy access later.
	 */
	if (hp.cth_parlabel != 0)
		fp->ctf_parlabel = ctf_strptr(fp, hp.cth_parlabel);
	if (hp.cth_parname != 0)
		fp->ctf_parname = ctf_strptr(fp, hp.cth_parname);

	ctf_dprintf("ctf_bufopen: parent name %s (label %s)\n",
	    fp->ctf_parname ? fp->ctf_parname : "<NULL>",
	    fp->ctf_parlabel ? fp->ctf_parlabel : "<NULL>");

	/*
	 * If we have a symbol table section, allocate and initialize
	 * the symtab translation table, pointed to by ctf_sxlate.
	 */
	if (symsect != NULL) {
		fp->ctf_nsyms = symsect->cts_size / symsect->cts_entsize;
		fp->ctf_sxlate = ctf_alloc(fp->ctf_nsyms * sizeof (uint_t));

		if (fp->ctf_sxlate == NULL) {
			(void) ctf_set_open_errno(errp, EAGAIN);
			goto bad;
		}

		if ((err = init_symtab(fp, &hp, symsect, strsect)) != 0) {
			(void) ctf_set_open_errno(errp, err);
			goto bad;
		}
	}

	if ((err = init_types(fp, &hp)) != 0) {
		(void) ctf_set_open_errno(errp, err);
		goto bad;
	}

	/*
	 * Initialize the ctf_lookup_by_name top-level dictionary.  We keep an
	 * array of type name prefixes and the corresponding ctf_hash to use.
	 * NOTE: This code must be kept in sync with the code in ctf_update().
	 */
	fp->ctf_lookups[0].ctl_prefix = "struct";
	fp->ctf_lookups[0].ctl_len = strlen(fp->ctf_lookups[0].ctl_prefix);
	fp->ctf_lookups[0].ctl_hash = &fp->ctf_structs;
	fp->ctf_lookups[1].ctl_prefix = "union";
	fp->ctf_lookups[1].ctl_len = strlen(fp->ctf_lookups[1].ctl_prefix);
	fp->ctf_lookups[1].ctl_hash = &fp->ctf_unions;
	fp->ctf_lookups[2].ctl_prefix = "enum";
	fp->ctf_lookups[2].ctl_len = strlen(fp->ctf_lookups[2].ctl_prefix);
	fp->ctf_lookups[2].ctl_hash = &fp->ctf_enums;
	fp->ctf_lookups[3].ctl_prefix = _CTF_NULLSTR;
	fp->ctf_lookups[3].ctl_len = strlen(fp->ctf_lookups[3].ctl_prefix);
	fp->ctf_lookups[3].ctl_hash = &fp->ctf_names;
	fp->ctf_lookups[4].ctl_prefix = NULL;
	fp->ctf_lookups[4].ctl_len = 0;
	fp->ctf_lookups[4].ctl_hash = NULL;

	if (symsect != NULL) {
		if (symsect->cts_entsize == sizeof (Elf64_Sym))
			(void) ctf_setmodel(fp, CTF_MODEL_LP64);
		else
			(void) ctf_setmodel(fp, CTF_MODEL_ILP32);
	} else
		(void) ctf_setmodel(fp, CTF_MODEL_NATIVE);

	fp->ctf_refcnt = 1;
	return (fp);

bad:
	ctf_close(fp);
	return (NULL);
}

/*
 * Close the specified CTF container and free associated data structures.  Note
 * that ctf_close() is a reference counted operation: if the specified file is
 * the parent of other active containers, its reference count will be greater
 * than one and it will be freed later when no active children exist.
 */
void
ctf_close(ctf_file_t *fp)
{
	ctf_dtdef_t *dtd, *ntd;
	ctf_dmdef_t *dmd, *nmd;

	if (fp == NULL)
		return; /* allow ctf_close(NULL) to simplify caller code */

	ctf_dprintf("ctf_close(%p) refcnt=%u\n", (void *)fp, fp->ctf_refcnt);

	if (fp->ctf_refcnt > 1) {
		fp->ctf_refcnt--;
		return;
	}

	for (dtd = ctf_list_next(&fp->ctf_dtdefs); dtd != NULL; dtd = ntd) {
		switch (CTF_INFO_KIND(dtd->dtd_data.ctt_info)) {
		case CTF_K_STRUCT:
		case CTF_K_UNION:
		case CTF_K_ENUM:
			for (dmd = ctf_list_next(&dtd->dtd_u.dtu_members);
			    dmd != NULL; dmd = nmd) {
				if (dmd->dmd_name != NULL) {
					ctf_free(dmd->dmd_name,
					    strlen(dmd->dmd_name) + 1);
				}
				nmd = ctf_list_next(dmd);
				ctf_free(dmd, sizeof (ctf_dmdef_t));
			}
			break;
		case CTF_K_FUNCTION:
			ctf_free(dtd->dtd_u.dtu_argv, sizeof (ctf_id_t) *
			    CTF_INFO_VLEN(dtd->dtd_data.ctt_info));
			break;
		}

		if (dtd->dtd_name != NULL)
			ctf_free(dtd->dtd_name, strlen(dtd->dtd_name) + 1);

		ntd = ctf_list_next(dtd);
		ctf_free(dtd, sizeof (ctf_dtdef_t));
	}

	if (fp->ctf_parent != NULL)
		ctf_close(fp->ctf_parent);

	if (fp->ctf_flags & LCTF_MMAP) {
		if (fp->ctf_data.cts_data != NULL)
			ctf_sect_munmap(&fp->ctf_data);
		if (fp->ctf_symtab.cts_data != NULL)
			ctf_sect_munmap(&fp->ctf_symtab);
		if (fp->ctf_strtab.cts_data != NULL)
			ctf_sect_munmap(&fp->ctf_strtab);
	}

	if (fp->ctf_data.cts_name != _CTF_NULLSTR &&
	    fp->ctf_data.cts_name != NULL) {
		ctf_free((char *)fp->ctf_data.cts_name,
		    strlen(fp->ctf_data.cts_name) + 1);
	}

	if (fp->ctf_symtab.cts_name != _CTF_NULLSTR &&
	    fp->ctf_symtab.cts_name != NULL) {
		ctf_free((char *)fp->ctf_symtab.cts_name,
		    strlen(fp->ctf_symtab.cts_name) + 1);
	}

	if (fp->ctf_strtab.cts_name != _CTF_NULLSTR &&
	    fp->ctf_strtab.cts_name != NULL) {
		ctf_free((char *)fp->ctf_strtab.cts_name,
		    strlen(fp->ctf_strtab.cts_name) + 1);
	}

	if (fp->ctf_base != fp->ctf_data.cts_data && fp->ctf_base != NULL)
		ctf_data_free((void *)fp->ctf_base, fp->ctf_size);

	if (fp->ctf_sxlate != NULL)
		ctf_free(fp->ctf_sxlate, sizeof (uint_t) * fp->ctf_nsyms);

	if (fp->ctf_txlate != NULL) {
		ctf_free(fp->ctf_txlate,
		    sizeof (uint_t) * (fp->ctf_typemax + 1));
	}

	if (fp->ctf_ptrtab != NULL) {
		ctf_free(fp->ctf_ptrtab,
		    sizeof (ushort_t) * (fp->ctf_typemax + 1));
	}

	ctf_hash_destroy(&fp->ctf_structs);
	ctf_hash_destroy(&fp->ctf_unions);
	ctf_hash_destroy(&fp->ctf_enums);
	ctf_hash_destroy(&fp->ctf_names);

	ctf_free(fp, sizeof (ctf_file_t));
}

/*
 * Return the CTF handle for the parent CTF container, if one exists.
 * Otherwise return NULL to indicate this container has no imported parent.
 */
ctf_file_t *
ctf_parent_file(ctf_file_t *fp)
{
	return (fp->ctf_parent);
}

/*
 * Return the name of the parent CTF container, if one exists.  Otherwise
 * return NULL to indicate this container is a root container.
 */
const char *
ctf_parent_name(ctf_file_t *fp)
{
	return (fp->ctf_parname);
}

/*
 * Import the types from the specified parent container by storing a pointer
 * to it in ctf_parent and incrementing its reference count.  Only one parent
 * is allowed: if a parent already exists, it is replaced by the new parent.
 */
int
ctf_import(ctf_file_t *fp, ctf_file_t *pfp)
{
	if (fp == NULL || fp == pfp || (pfp != NULL && pfp->ctf_refcnt == 0))
		return (ctf_set_errno(fp, EINVAL));

	if (pfp != NULL && pfp->ctf_dmodel != fp->ctf_dmodel)
		return (ctf_set_errno(fp, ECTF_DMODEL));

	if (fp->ctf_parent != NULL)
		ctf_close(fp->ctf_parent);

	if (pfp != NULL) {
		fp->ctf_flags |= LCTF_CHILD;
		pfp->ctf_refcnt++;
	}

	fp->ctf_parent = pfp;
	return (0);
}

/*
 * Set the data model constant for the CTF container.
 */
int
ctf_setmodel(ctf_file_t *fp, int model)
{
	const ctf_dmodel_t *dp;

	for (dp = _libctf_models; dp->ctd_name != NULL; dp++) {
		if (dp->ctd_code == model) {
			fp->ctf_dmodel = dp;
			return (0);
		}
	}

	return (ctf_set_errno(fp, EINVAL));
}

/*
 * Return the data model constant for the CTF container.
 */
int
ctf_getmodel(ctf_file_t *fp)
{
	return (fp->ctf_dmodel->ctd_code);
}