mroe

source/util/src/encode.c

+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "encode.h"
+#include "freelist.h"
+
+#define CODER_NODE_FIELDS \
+  uint8_t* data;          \
+  int32_t  size;          \
+  int32_t  pos;
+
+struct SCoderNode {
+  TD_SLIST_NODE(SCoderNode);
+  CODER_NODE_FIELDS
+};
+
+typedef struct {
+  td_endian_t endian;
+  SFreeList   fl;
+  CODER_NODE_FIELDS
+  TD_SLIST(SCoderNode) stack;
+} SCoder;
+
+bool tDecodeIsEnd(SCoder* pCoder) { return (pCoder->size == pCoder->pos); }
+
+void tCoderInit(SCoder* pCoder, td_endian_t endian, uint8_t* data, int32_t size) {
+  pCoder->endian = endian;
+  pCoder->data = data;
+  pCoder->size = size;
+  pCoder->pos = 0;
+  tFreeListInit(&(pCoder->fl));
+  TD_SLIST_INIT(&(pCoder->stack));
+}
+
+void tCoderClear(SCoder* pCoder) {
+  tFreeListClear(&(pCoder->fl));
+  struct SCoderNode* pNode;
+  for (;;) {
+    pNode = TD_SLIST_HEAD(&(pCoder->stack));
+    if (pNode == NULL) break;
+    TD_SLIST_POP(&(pCoder->stack));
+    free(pNode);
+  }
+}
+
+int tStartEncode(SCoder* pCoder) {
+  if (pCoder->data) {
+    struct SCoderNode* pNode = malloc(sizeof(*pNode));
+    if (pNode == NULL) return -1;
+
+    pNode->data = pCoder->data;
+    pNode->pos = pCoder->pos;
+    pNode->size = pCoder->size;
+
+    pCoder->data = pNode->data + sizeof(int32_t);
+    pCoder->pos = 0;
+    pCoder->size = pNode->size - pNode->pos - sizeof(int32_t);
+
+    TD_SLIST_PUSH(&(pCoder->stack), pNode);
+  } else {
+    pCoder->pos += sizeof(int32_t);
+  }
+  return 0;
+}
+
+void tEndEncode(SCoder* pCoder) {
+  struct SCoderNode* pNode;
+
+  if (pCoder->data) {
+    pNode = TD_SLIST_HEAD(&(pCoder->stack));
+    ASSERT(pNode);
+    TD_SLIST_POP(&(pCoder->stack));
+
+    // TODO: tEncodeI32(pNode, pCoder->pos);
+
+    pCoder->data = pNode->data;
+    pCoder->size = pNode->size;
+    pCoder->pos = pNode->pos + pCoder->pos;
+
+    free(pNode);
+  }
+}
+
+int tStartDecode(SCoder* pCoder) {
+  int32_t            size;
+  struct SCoderNode* pNode;
+
+  pNode = malloc(sizeof(*pNode));
+  if (pNode == NULL) return -1;
+
+  // TODO: tDecodeI32(pCoder, &size);
+
+  pNode->data = pCoder->data;
+  pNode->pos = pCoder->pos;
+  pNode->size = pCoder->size;
+
+  pCoder->data = pCoder->data;
+  pCoder->size = size;
+  pCoder->pos = 0;
+
+  TD_SLIST_PUSH(&(pCoder->stack), pNode);
+
+  return 0;
+}
+
+void tEndDecode(SCoder* pCoder) {
+  ASSERT(tDecodeIsEnd(pCoder));
+
+  struct SCoderNode* pNode;
+
+  pNode = TD_SLIST_HEAD(&(pCoder->stack));
+  ASSERT(pNode);
+  TD_SLIST_POP(&(pCoder->stack));
+
+  pCoder->data = pNode->data;
+  pCoder->size = pNode->size;
+  pCoder->pos = pCoder->pos + pNode->pos;
+
+  free(pNode);
+}