Merge branch 'jk/blame-commit-label' into maint

"git blame HEAD -- missing" failed to correctly say "HEAD" when it
tried to say "No such path 'missing' in HEAD".

* jk/blame-commit-label:
  blame.c: fix garbled error message
  use xstrdup_or_null to replace ternary conditionals
  builtin/commit.c: use xstrdup_or_null instead of envdup
  builtin/apply.c: use xstrdup_or_null instead of null_strdup
  git-compat-util: add xstrdup_or_null helper

diff --cc builtin/apply.c
Simple merge

diff --cc builtin/blame.c
Simple merge

diff --cc builtin/commit.c
Simple merge

diff --cc config.c
Simple merge

diff --cc git-compat-util.h
Simple merge

diff --cc grep.c
Simple merge

diff --cc notes.c
Simple merge

diff --cc refs.c
index ed3b2cb405cc576f16e5b94d83683953b94e1e89,32dce4e41c377cbafbf9ede5f31bd1680a4e20ae..9edf18b04e7e29b12fa3808aab2239efcc404dca
--- 1/refs.c
--- 2/refs.c
+++ b/refs.c
@@@ -1616,10 -1526,10 +1616,9 @@@ const char *resolve_ref_unsafe(const ch
        }
  }
  
 -char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
 +char *resolve_refdup(const char *ref, int resolve_flags, unsigned char *sha1, int *flags)
  {
-       const char *ret = resolve_ref_unsafe(ref, resolve_flags, sha1, flags);
-       return ret ? xstrdup(ret) : NULL;
 -      return xstrdup_or_null(resolve_ref_unsafe(ref, sha1, reading, flag));
++      return xstrdup_or_null(resolve_ref_unsafe(ref, resolve_flags, sha1, flags));
  }
  
  /* The argument to filter_refs */

diff --cc remote.c
Simple merge

diff --cc shallow.c
Simple merge

diff --cc walker.c
Simple merge