util: Introduce unquote_first_word_and_warn

It will try to unquot_first_word, but if it runs into escaping problems
it will retry it adding UNQUOTE_CUNESCAPE_RELAX to the flags.  If it
succeeds on the second try, it will log a warning about it.  If it fails
both times, it will log an error.

Add test cases to confirm it behaves as expected.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/basic/util.h b/src/basic/util.h
index 748f22f1a2..a1d1dd15c3 100644
--- a/src/basic/util.h
+++ b/src/basic/util.h
@@ -845,6 +845,7 @@ typedef enum UnquoteFlags {
 } UnquoteFlags;
 
 int unquote_first_word(const char **p, char **ret, UnquoteFlags flags);
+int unquote_first_word_and_warn(const char **p, char **ret, UnquoteFlags flags, const char *unit, const char *filename, unsigned line, const char *rvalue);
 int unquote_many_words(const char **p, UnquoteFlags flags, ...) _sentinel_;
 
 int free_and_strdup(char **p, const char *s);