// Copyright 2020 Google LLC

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

//

//      http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

//

///////////////////////////////////////////////////////////////////////////////

#include "postgres.h"

#include "access/xlog.h"

#include "access/xact.h"

#include "common/username.h"

#include "executor/spi.h"

#include "jit/jit.h"

#include "libpq/libpq.h"

#include "libpq/pqsignal.h"

#include "miscadmin.h"

#include "optimizer/optimizer.h"

#include "parser/analyze.h"

#include "parser/parser.h"

#include "storage/proc.h"

#include "tcop/tcopprot.h"

#include "utils/datetime.h"

#include "utils/memutils.h"

#include "utils/portal.h"

#include "utils/snapmgr.h"

#include "utils/timeout.h"

static void exec_simple_query(const char *query_string) {

  MemoryContext oldcontext;

  List *parsetree_list;

  ListCell *parsetree_item;

  oldcontext = MemoryContextSwitchTo(MessageContext);

  parsetree_list = raw_parser(query_string, RAW_PARSE_TYPE_NAME);

  MemoryContextSwitchTo(oldcontext);

  foreach (parsetree_item, parsetree_list) {

    RawStmt *parsetree = lfirst_node(RawStmt, parsetree_item);

    MemoryContext per_parsetree_context = NULL;

    List *querytree_list;

    if (lnext(parsetree_list, parsetree_item) != NULL) {

      per_parsetree_context =

          AllocSetContextCreate(MessageContext, "per-parsetree message context", ALLOCSET_DEFAULT_SIZES);

      oldcontext = MemoryContextSwitchTo(per_parsetree_context);

    } else {

      oldcontext = MemoryContextSwitchTo(MessageContext);

    }

    querytree_list = pg_analyze_and_rewrite_fixedparams(parsetree, query_string, NULL, 0, NULL);

    pg_plan_queries(querytree_list, query_string, CURSOR_OPT_PARALLEL_OK, NULL);

    if (per_parsetree_context) {

      MemoryContextDelete(per_parsetree_context);

    } else {

      MemoryContextSwitchTo(oldcontext);

    }

  }

}

int LLVMFuzzerInitialize(int *argc, char ***argv) {

  MemoryContextInit();

  InitializeGUCOptions();

  InitializeMaxBackends();

  MessageContext = AllocSetContextCreate(TopMemoryContext,

                                         "MessageContext",

                                         ALLOCSET_DEFAULT_SIZES);

  return 0;

}

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {

  if (size == 0)

    return 0;

  sigjmp_buf local_sigjmp_buf;

  char *query_string = (char *) calloc(size + 1, sizeof(char));

  memcpy(query_string, data, size);

  if (!sigsetjmp(local_sigjmp_buf, 0)) {

    PG_exception_stack = &local_sigjmp_buf;

    error_context_stack = NULL;

    set_stack_base();

    disable_all_timeouts(false);

    QueryCancelPending = false;

    pq_comm_reset();

    EmitErrorReport();

    jit_reset_after_error();

    MemoryContextSwitchTo(TopMemoryContext);

    FlushErrorState();

    MemoryContextSwitchTo(MessageContext);

    MemoryContextReset(MessageContext);

    SetCurrentStatementStartTimestamp();

    exec_simple_query(query_string);

  }

  free(query_string);

  return 0;

}