Assert that some xasprintf calls return non-NULL

"gcc -fanalyzer" notices that xasprintf can return NULL in some
situations (string length > INT_MAX, invalid format string, or multibyte
conversion error), and that we weren't handling this in various cases
where we use the return value in contexts that require non-NULL values.
The situations seem obscure enough for simple asserts to be appropriate.

* lib/pathsearch.c (pathsearch): Assert that xasprintf returns non-NULL.
* lib/tempfile.c (create_tempdir): Likewise.
* lib/util.c (remove_directory): Likewise.
* libdb/db_lookup.c (make_multi_key): Likewise.
* libdb/db_store.c (make_content, dbstore): Likewise.
* src/check_mandirs.c (add_dir_entries, fix_permissions_tree): Likewise.
* src/compression.c (comp_file): Likewise.
* src/globbing.c (look_for_file): Likewise.
* src/man.c (main): Likewise.
* src/mandb.c (mandb, purge_catsubdirs): Likewise.
* src/manp.c (pathappend): Likewise.
* src/ult_src.c (find_include): Likewise.
* src/whatis.c (use_grep): Likewise.
* src/zsoelim.l (zsoelim_open_file): Likewise.

1 files changed, 2 insertions, 0 deletions

diff --git a/src/man.c b/src/man.c
index cb00f9e7..b15c90a1 100644
--- a/src/man.c
+++ b/src/man.c
@@ -4264,6 +4264,7 @@ int main (int argc, char *argv[])
 			if (subpages && first_arg < argc) {
 				char *subname = xasprintf (
 					"%s-%s", nextarg, argv[first_arg]);
+				assert (subname);
 				status = man (subname, &found);
 				free (subname);
 				if (status == OK) {
@@ -4274,6 +4275,7 @@ int main (int argc, char *argv[])
 			if (!found_subpage && subpages && first_arg < argc) {
 				char *subname = xasprintf (
 					"%s_%s", nextarg, argv[first_arg]);
+				assert (subname);
 				status = man (subname, &found);
 				free (subname);
 				if (status == OK) {