reftable: make reftable-record.h function signatures const correct

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

reftable/record.c

@@ -72,7 +72,7 @@ int reftable_is_block_type(uint8_t typ)
 	return 0;
 }
 
-uint8_t *reftable_ref_record_val1(struct reftable_ref_record *rec)
+uint8_t *reftable_ref_record_val1(const struct reftable_ref_record *rec)
 {
 	switch (rec->value_type) {
 	case REFTABLE_REF_VAL1:
@@ -84,7 +84,7 @@ uint8_t *reftable_ref_record_val1(struct reftable_ref_record *rec)
 	}
 }
 
-uint8_t *reftable_ref_record_val2(struct reftable_ref_record *rec)
+uint8_t *reftable_ref_record_val2(const struct reftable_ref_record *rec)
 {
 	switch (rec->value_type) {
 	case REFTABLE_REF_VAL2:
@@ -251,7 +251,7 @@ static void hex_format(char *dest, uint8_t *src, int hash_size)
 	}
 }
 
-void reftable_ref_record_print(struct reftable_ref_record *ref,
+void reftable_ref_record_print(const struct reftable_ref_record *ref,
 			       uint32_t hash_id)
 {
 	char hex[GIT_MAX_HEXSZ + 1] = { 0 }; /* BUG */
@@ -881,8 +881,8 @@ static int zero_hash_eq(uint8_t *a, uint8_t *b, int sz)
 	return !memcmp(a, b, sz);
 }
 
-int reftable_log_record_equal(struct reftable_log_record *a,
-			      struct reftable_log_record *b, int hash_size)
+int reftable_log_record_equal(const struct reftable_log_record *a,
+			      const struct reftable_log_record *b, int hash_size)
 {
 	if (!(null_streq(a->refname, b->refname) &&
 	      a->update_index == b->update_index &&
@@ -1150,8 +1150,8 @@ static int hash_equal(uint8_t *a, uint8_t *b, int hash_size)
 	return a == b;
 }
 
-int reftable_ref_record_equal(struct reftable_ref_record *a,
-			      struct reftable_ref_record *b, int hash_size)
+int reftable_ref_record_equal(const struct reftable_ref_record *a,
+			      const struct reftable_ref_record *b, int hash_size)
 {
 	assert(hash_size > 0);
 	if (!null_streq(a->refname, b->refname))

reftable/reftable-record.h

@@ -49,25 +49,25 @@ struct reftable_ref_record {
 
 /* Returns the first hash, or NULL if `rec` is not of type
  * REFTABLE_REF_VAL1 or REFTABLE_REF_VAL2. */
-uint8_t *reftable_ref_record_val1(struct reftable_ref_record *rec);
+uint8_t *reftable_ref_record_val1(const struct reftable_ref_record *rec);
 
 /* Returns the second hash, or NULL if `rec` is not of type
  * REFTABLE_REF_VAL2. */
-uint8_t *reftable_ref_record_val2(struct reftable_ref_record *rec);
+uint8_t *reftable_ref_record_val2(const struct reftable_ref_record *rec);
 
 /* returns whether 'ref' represents a deletion */
 int reftable_ref_record_is_deletion(const struct reftable_ref_record *ref);
 
 /* prints a reftable_ref_record onto stdout. Useful for debugging. */
-void reftable_ref_record_print(struct reftable_ref_record *ref,
+void reftable_ref_record_print(const struct reftable_ref_record *ref,
 			       uint32_t hash_id);
 
 /* frees and nulls all pointer values inside `ref`. */
 void reftable_ref_record_release(struct reftable_ref_record *ref);
 
 /* returns whether two reftable_ref_records are the same. Useful for testing. */
-int reftable_ref_record_equal(struct reftable_ref_record *a,
-			      struct reftable_ref_record *b, int hash_size);
+int reftable_ref_record_equal(const struct reftable_ref_record *a,
+			      const struct reftable_ref_record *b, int hash_size);
 
 /* reftable_log_record holds a reflog entry */
 struct reftable_log_record {
@@ -104,8 +104,8 @@ int reftable_log_record_is_deletion(const struct reftable_log_record *log);
 void reftable_log_record_release(struct reftable_log_record *log);
 
 /* returns whether two records are equal. Useful for testing. */
-int reftable_log_record_equal(struct reftable_log_record *a,
-			      struct reftable_log_record *b, int hash_size);
+int reftable_log_record_equal(const struct reftable_log_record *a,
+			      const struct reftable_log_record *b, int hash_size);
 
 /* dumps a reftable_log_record on stdout, for debugging/testing. */
 void reftable_log_record_print(struct reftable_log_record *log,