btree的key支持msgpack格式，用于排序

bdb/bdb.c

@@ -1,9 +1,13 @@
 #include <errno.h>
 #include <stdlib.h>
 #include <string.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
 #include <db.h>
 #include "rep_common.h"
 #include "bdb.h"
+#include "cmp.h"
 
 void
 log_error(const char *file, const char *function, int line, const char *msg, int err) {
@@ -159,7 +163,105 @@ db_put(DB *dbp, DB_TXN *txn, char *_key, unsigned int keylen, char *_data, unsig
  return ret;
 }
 
-int
+struct msgpack_reader_ctx {
+ char *buf;
+ int pos;
+ int len;
+};
+
+static bool
+msgpack_reader(cmp_ctx_t *ctx, void *data, size_t limit) {
+ struct msgpack_reader_ctx *reader = (struct msgpack_reader_ctx*)ctx->buf;
+ if (reader->pos + limit > reader->len) {
+ return false;
+ }
+ memcpy(data, reader->buf + reader->pos, limit);
+ reader->pos += limit;
+ return true;
+}
+
+static int
+msgpack_compare(cmp_ctx_t *cmp1, cmp_ctx_t *cmp2);
+
+static int
+msgpack_compare_array(cmp_ctx_t *cmp1, cmp_ctx_t *cmp2, int c) {
+ int i;
+ int r;
+
+ for (i = 0; i < c; ++i) {
+ r = msgpack_compare(cmp1, cmp2);
+ if (r != 0) {
+ return r;
+ }
+ }
+ return 0;
+}
+
+static int
+msgpack_compare(cmp_ctx_t *cmp1, cmp_ctx_t *cmp2) {
+ cmp_object_t obj1, obj2;
+ int64_t r;
+ char buf1[512], buf2[512];
+
+ if (!cmp_read_object(cmp1, &obj1)) {
+ Error("cmp1_read_object");
+ return 0;
+ }
+ if (!cmp_read_object(cmp2, &obj2)) {
+ Error("cmp2_read_object");
+ return 0;
+ }
+ if (obj1.type != obj2.type) {
+ Error("cmp_type_diff");
+ return 0;
+ }
+ switch (obj1.type) {
+ case CMP_TYPE_FIXARRAY:
+ case CMP_TYPE_ARRAY16:
+ case CMP_TYPE_ARRAY32:
+ return msgpack_compare_array(cmp1, cmp2, obj1.as.array_size);
+ case CMP_TYPE_SINT64:
+ return obj1.as.s64 - obj1.as.s64;
+ case CMP_TYPE_FIXSTR:
+ case CMP_TYPE_STR8:
+ case CMP_TYPE_STR16:
+ case CMP_TYPE_STR32:
+ if (obj1.as.str_size >= sizeof buf1 || obj2.as.str_size >= sizeof buf2) {
+ Error("cmp_str_too_long");
+ return 0;
+ }
+ msgpack_reader(cmp1, buf1, obj1.as.str_size);
+ buf1[obj1.as.str_size] = 0;
+ msgpack_reader(cmp2, buf2, obj2.as.str_size);
+ buf2[obj2.as.str_size] = 0;
+ return strcmp(buf1, buf2);
+ default:
+ Error("cmp|obj.type");
+ return 0;
+ }
+}
+
+static int
+btree_key_compare(DB *db, const DBT *a, const DBT *b, size_t *locp) {
+ int64_t r;
+ struct msgpack_reader_ctx reader1, reader2;
+ cmp_ctx_t cmp1, cmp2;
+
+ reader1.buf = a->data;
+ reader1.pos = 0;
+ reader1.len = a->size;
+
+ reader2.buf = b->data;
+ reader2.pos = 0;
+ reader2.len = b->size;
+
+ cmp_init(&cmp1, &reader1, msgpack_reader, NULL);
+ cmp_init(&cmp2, &reader2, msgpack_reader, NULL);
+
+ return msgpack_compare(&cmp1, &cmp2);
+}
+
+static int
 expire_key_compare(DB *db, const DBT *a, const DBT *b, size_t *locp) {
  struct expire_key *ai, *bi;
  int64_t r;

bdb/bdb.h

@@ -41,7 +41,6 @@ int get_db(DB_ENV *dbenv, SHARED_DATA *shared_data, const char *name, int dbtype
 int is_finished(SHARED_DATA *shared_data);
 
 void split_key(char *_key, int keylen, char **table, int *tablelen, char **name, int *namelen);
-int expire_key_compare(DB *db, const DBT *a, const DBT *b, size_t *locp);
 
 int txn_begin(DB_ENV *dbenv, DB_TXN **txn, unsigned int flags);
 int txn_abort(DB_TXN *txn);