libctf, dedup: add deduplicator

This adds the core deduplicator that the ctf_link machinery calls
(possibly repeatedly) to link the CTF sections: it takes an array
of input ctf_file_t's and another array that indicates which entries in
the input array are parents of which other entries, and returns an array
of outputs.  The first output is always the ctf_file_t on which
ctf_link/ctf_dedup/etc was called: the other outputs are child dicts
that have the first output as their parent.

include/
	* ctf-api.h (CTF_LINK_SHARE_DUPLICATED): No longer unimplemented.
libctf/
	* ctf-impl.h (ctf_type_id_key): New, the key in the
	cd_id_to_file_t.
	(ctf_dedup): New, core deduplicator state.
	(ctf_file_t) <ctf_dedup>: New.
	<ctf_dedup_atoms>: New.
	<ctf_dedup_atoms_alloc>: New.
	(ctf_hash_type_id_key): New prototype.
	(ctf_hash_eq_type_id_key): Likewise.
	(ctf_dedup_atoms_init): Likewise.
	* ctf-hash.c (ctf_hash_eq_type_id_key): New.
	(ctf_dedup_atoms_init): Likewise.
	* ctf-create.c (ctf_serialize): Adjusted.
	(ctf_add_encoded): No longer static.
	(ctf_add_reftype): Likewise.
	* ctf-open.c (ctf_file_close): Destroy the
	ctf_dedup_atoms_alloc.
	* ctf-dedup.c: New file.
        * ctf-decls.h [!HAVE_DECL_STPCPY]: Add prototype.
	* configure.ac: Check for stpcpy.
	* Makefile.am: Add it.
	* Makefile.in: Regenerate.
        * config.h.in: Regenerate.
        * configure: Regenerate.

1 files changed, 22 insertions, 0 deletions

diff --git a/libctf/ctf-hash.c b/libctf/ctf-hash.c
index ed06f1f..2975260 100644
--- a/libctf/ctf-hash.c
+++ b/libctf/ctf-hash.c
@@ -117,6 +117,28 @@ ctf_hash_eq_type_key (const void *a, const void *b)
     && (key_a->cltk_idx == key_b->cltk_idx);
 }
 
+/* Hash a type_id_key.  */
+unsigned int
+ctf_hash_type_id_key (const void *ptr)
+{
+  ctf_helem_t *hep = (ctf_helem_t *) ptr;
+  ctf_type_id_key_t *k = (ctf_type_id_key_t *) hep->key;
+
+  return htab_hash_pointer ((void *) (uintptr_t) k->ctii_input_num)
+    + 59 * htab_hash_pointer ((void *) (uintptr_t) k->ctii_type);
+}
+
+int
+ctf_hash_eq_type_id_key (const void *a, const void *b)
+{
+  ctf_helem_t *hep_a = (ctf_helem_t *) a;
+  ctf_helem_t *hep_b = (ctf_helem_t *) b;
+  ctf_type_id_key_t *key_a = (ctf_type_id_key_t *) hep_a->key;
+  ctf_type_id_key_t *key_b = (ctf_type_id_key_t *) hep_b->key;
+
+  return (key_a->ctii_input_num == key_b->ctii_input_num)
+    && (key_a->ctii_type == key_b->ctii_type);
+}
 
 /* Hash and eq functions for the dynset.  Most of these can just use the
    underlying hashtab functions directly.   */