libxbps: performance improvements by caching the most accessed paths.

1- We can cache the result of the first xbps_pkgdb_init() when it fails
   and avoid the malloc/free/access from it.
2- We cache the uname(2) result into a private var in xbps_handle and
   use it in xbps_pkg_arch_match().

This improves performance by ~5% approx and it's close as it was before
introducing the repository index format 1.5.

bin/xbps-bin/check_pkg_requiredby.c

@@ -168,7 +168,7 @@ remove_stale_entries_in_reqby(struct xbps_handle *xhp,
 		}
 		printf("%s: found stale entry in requiredby `%s' (fixed)\n",
 		    crd->pkgver, str);
-		if (xbps_remove_string_from_array(crd->pkgd_reqby, str))
+		if (xbps_remove_string_from_array(xhp, crd->pkgd_reqby, str))
 			needs_update = true;
 	}
 	if (needs_update) {

bin/xbps-bin/list.c

@@ -49,7 +49,7 @@ list_pkgs_in_dict(struct xbps_handle *xhp,
 	(void)loop_done;
 
 	chkarch = prop_dictionary_get_cstring_nocopy(obj, "architecture", &arch);
-	if (chkarch && !xbps_pkg_arch_match(arch, NULL))
+	if (chkarch && !xbps_pkg_arch_match(xhp, arch, NULL))
 		return 0;
 
 	if (lpc->check_state) {

bin/xbps-repo/find-files.c

@@ -39,7 +39,9 @@ struct ffdata {
 };
 
 static void
-match_files_by_pattern(prop_dictionary_t pkg_filesd, struct ffdata *ffd)
+match_files_by_pattern(struct xbps_handle *xhp,
+		       prop_dictionary_t pkg_filesd,
+		       struct ffdata *ffd)
 {
 	prop_array_t array;
 	const char *filestr, *pkgver, *arch;
@@ -47,7 +49,7 @@ match_files_by_pattern(prop_dictionary_t pkg_filesd, struct ffdata *ffd)
 	int x;
 
 	prop_dictionary_get_cstring_nocopy(pkg_filesd, "architecture", &arch);
-	if (!xbps_pkg_arch_match(arch, NULL))
+	if (!xbps_pkg_arch_match(xhp, arch, NULL))
 		return;
 
 	array = prop_dictionary_get(pkg_filesd, "files");
@@ -94,7 +96,7 @@ find_files_in_package(struct xbps_handle *xhp,
 	ffd->repouri = rpi->uri;
 
 	for (i = 0; i < prop_array_count(idxfiles); i++)
-		match_files_by_pattern(prop_array_get(idxfiles, i), ffd);
+		match_files_by_pattern(xhp, prop_array_get(idxfiles, i), ffd);
 
 	prop_object_release(idxfiles);
 	return 0;

bin/xbps-repo/index-files.c

@@ -56,7 +56,7 @@ rmobsoletes_files_cb(struct xbps_handle *xhp,
 
 	prop_dictionary_get_cstring_nocopy(obj, "pkgver", &pkgver);
 	prop_dictionary_get_cstring_nocopy(obj, "architecture", &arch);
-	if (xbps_find_pkg_in_array_by_pkgver(ifd->idx, pkgver, arch)) {
+	if (xbps_find_pkg_in_array_by_pkgver(xhp, ifd->idx, pkgver, arch)) {
 		/* pkg found, do nothing */
 		return 0;
 	}
@@ -95,7 +95,7 @@ genindex_files_cb(struct xbps_handle *xhp,
 	prop_dictionary_get_cstring_nocopy(obj, "pkgver", &pkgver);
 	prop_dictionary_get_cstring_nocopy(obj, "architecture", &arch);
 
-	if (xbps_find_pkg_in_array_by_pkgver(ifd->idxfiles, pkgver, arch))  {
+	if (xbps_find_pkg_in_array_by_pkgver(xhp, ifd->idxfiles, pkgver, arch))  {
 		fprintf(stderr, "index-files: skipping `%s' (%s), "
 		    "already registered.\n", pkgver, arch);
 		return 0;
@@ -278,7 +278,7 @@ repo_genindex_files(struct xbps_handle *xhp, const char *pkgdir)
 			}
 			arch = strchr(p, ',') + 1;
 			if (!xbps_remove_pkg_from_array_by_pkgver(
-			    ifd->idxfiles, pkgver, arch)) {
+			    xhp, ifd->idxfiles, pkgver, arch)) {
 				free(pkgver);
 				rv = EINVAL;
 				goto out;

bin/xbps-repo/index.c

@@ -129,7 +129,8 @@ repoidx_get(struct xbps_handle *xhp, const char *pkgdir)
 }
 
 static int
-add_binpkg_to_index(prop_array_t idx,
+add_binpkg_to_index(struct xbps_handle *xhp,
+		    prop_array_t idx,
 		    const char *filedir,
 		    const char *file)
 {
@@ -165,7 +166,7 @@ add_binpkg_to_index(prop_array_t idx,
 	 * than current registered package, update the index; otherwise
 	 * pass to the next one.
 	 */
-	curpkgd = xbps_find_pkg_in_array_by_name(idx, pkgname, arch);
+	curpkgd = xbps_find_pkg_in_array_by_name(xhp, idx, pkgname, arch);
 	if (curpkgd == NULL) {
 		if (errno && errno != ENOENT) {
 			prop_object_release(newpkgd);
@@ -236,7 +237,8 @@ add_binpkg_to_index(prop_array_t idx,
 			goto out;
 		}
 		free(oldfilepath);
-		if (!xbps_remove_pkg_from_array_by_pkgver(idx, buf, oldarch)) {
+		if (!xbps_remove_pkg_from_array_by_pkgver(xhp, idx,
+		    buf, oldarch)) {
 			xbps_error_printf("failed to remove `%s' "
 			    "from plist index: %s\n", buf, strerror(errno));
 			prop_object_release(newpkgd);
@@ -350,7 +352,7 @@ repo_genindex(struct xbps_handle *xhp, const char *pkgdir)
 				rv = errno;
 				goto out;
 			}
-			rv = add_binpkg_to_index(idx, curdir, binfile);
+			rv = add_binpkg_to_index(xhp, idx, curdir, binfile);
 			free(binfile);
 			if (rv == EEXIST) {
 				rv = 0;

bin/xbps-repo/show.c

@@ -108,7 +108,7 @@ show_pkg_namedesc(struct xbps_handle *xhp,
 	(void)loop_done;
 
 	prop_dictionary_get_cstring_nocopy(obj, "architecture", &arch);
-	if (!xbps_pkg_arch_match(arch, NULL))
+	if (!xbps_pkg_arch_match(xhp, arch, NULL))
 		return 0;
 
 	prop_dictionary_get_cstring_nocopy(obj, "pkgname", &pkgname);