// Copyright 2007 - 2021, Alan Antonuk and the rabbitmq-c contributors.

// SPDX-License-Identifier: mit

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#ifdef _MSC_VER

#define _CRT_SECURE_NO_WARNINGS

#endif

#include "amqp_private.h"

#include "amqp_time.h"

#include "rabbitmq-c/tcp_socket.h"

#include <errno.h>

#include <stdint.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#ifndef AMQP_INITIAL_FRAME_POOL_PAGE_SIZE

#define AMQP_INITIAL_FRAME_POOL_PAGE_SIZE 65536

#endif

#ifndef AMQP_INITIAL_INBOUND_SOCK_BUFFER_SIZE

#define AMQP_INITIAL_INBOUND_SOCK_BUFFER_SIZE 131072

#endif

#ifndef AMQP_DEFAULT_LOGIN_TIMEOUT_SEC

#define AMQP_DEFAULT_LOGIN_TIMEOUT_SEC 12

#endif

#define ENFORCE_STATE(statevec, statenum)                                   \

  {                                                                         \

    amqp_connection_state_t _check_state = (statevec);                      \

    amqp_connection_state_enum _wanted_state = (statenum);                  \

    if (_check_state->state != _wanted_state)                               \

      amqp_abort(                                                           \

          "Programming error: invalid AMQP connection state: expected %d, " \

          "got %d",                                                         \

          _wanted_state, _check_state->state);                              \

  }

amqp_connection_state_t amqp_new_connection(void) {

  int res;

  amqp_connection_state_t state = (amqp_connection_state_t)calloc(

      1, sizeof(struct amqp_connection_state_t_));

  if (state == NULL) {

    return NULL;

  }

  res = amqp_tune_connection(state, 0, AMQP_INITIAL_FRAME_POOL_PAGE_SIZE, 0);

  if (0 != res) {

    goto out_nomem;

  }

  state->inbound_buffer.bytes = state->header_buffer;

  state->inbound_buffer.len = sizeof(state->header_buffer);

  state->state = CONNECTION_STATE_INITIAL;

  /* the server protocol version response is 8 bytes, which conveniently

     is also the minimum frame size */

  state->target_size = 8;

  state->sock_inbound_buffer.len = AMQP_INITIAL_INBOUND_SOCK_BUFFER_SIZE;

  state->sock_inbound_buffer.bytes =

      malloc(AMQP_INITIAL_INBOUND_SOCK_BUFFER_SIZE);

  if (state->sock_inbound_buffer.bytes == NULL) {

    goto out_nomem;

  }

  init_amqp_pool(&state->properties_pool, 512);

  /* Use address of the internal_handshake_timeout object by default. */

  state->internal_handshake_timeout.tv_sec = AMQP_DEFAULT_LOGIN_TIMEOUT_SEC;

  state->internal_handshake_timeout.tv_usec = 0;

  state->handshake_timeout = &state->internal_handshake_timeout;

  return state;

out_nomem:

  free(state->sock_inbound_buffer.bytes);

  free(state);

  return NULL;

}

int amqp_get_sockfd(amqp_connection_state_t state) {

  return state->socket ? amqp_socket_get_sockfd(state->socket) : -1;

}

void amqp_set_sockfd(amqp_connection_state_t state, int sockfd) {

  amqp_socket_t *socket = amqp_tcp_socket_new(state);

  if (!socket) {

    amqp_abort("%s", strerror(errno));

  }

  amqp_tcp_socket_set_sockfd(socket, sockfd);

}

void amqp_set_socket(amqp_connection_state_t state, amqp_socket_t *socket) {

  amqp_socket_delete(state->socket);

  state->socket = socket;

}

amqp_socket_t *amqp_get_socket(amqp_connection_state_t state) {

  return state->socket;

}

int amqp_tune_connection(amqp_connection_state_t state, int channel_max,

                         int frame_max, int heartbeat) {

  void *newbuf;

  int res;

  ENFORCE_STATE(state, CONNECTION_STATE_IDLE);

  state->channel_max = channel_max;

  state->frame_max = frame_max;

  state->heartbeat = heartbeat;

  if (0 > state->heartbeat) {

    state->heartbeat = 0;

  }

  res = amqp_time_s_from_now(&state->next_send_heartbeat,

                             amqp_heartbeat_send(state));

  if (AMQP_STATUS_OK != res) {

    return res;

  }

  res = amqp_time_s_from_now(&state->next_recv_heartbeat,

                             amqp_heartbeat_recv(state));

  if (AMQP_STATUS_OK != res) {

    return res;

  }

  state->outbound_buffer.len = frame_max;

  newbuf = realloc(state->outbound_buffer.bytes, frame_max);

  if (newbuf == NULL) {

    return AMQP_STATUS_NO_MEMORY;

  }

  state->outbound_buffer.bytes = newbuf;

  return AMQP_STATUS_OK;

}

int amqp_get_channel_max(amqp_connection_state_t state) {

  return state->channel_max;

}

int amqp_get_frame_max(amqp_connection_state_t state) {

  return state->frame_max;

}

int amqp_get_heartbeat(amqp_connection_state_t state) {

  return state->heartbeat;

}

int amqp_destroy_connection(amqp_connection_state_t state) {

  int status = AMQP_STATUS_OK;

  if (state) {

    int i;

    for (i = 0; i < POOL_TABLE_SIZE; ++i) {

      amqp_pool_table_entry_t *entry = state->pool_table[i];

      while (NULL != entry) {

        amqp_pool_table_entry_t *todelete = entry;

        empty_amqp_pool(&entry->pool);

        entry = entry->next;

        free(todelete);

      }

    }

    free(state->outbound_buffer.bytes);

    free(state->sock_inbound_buffer.bytes);

    amqp_socket_delete(state->socket);

    empty_amqp_pool(&state->properties_pool);

    free(state);

  }

  return status;

}

static void return_to_idle(amqp_connection_state_t state) {

  state->inbound_buffer.len = sizeof(state->header_buffer);

  state->inbound_buffer.bytes = state->header_buffer;

  state->inbound_offset = 0;

  state->target_size = HEADER_SIZE;

  state->state = CONNECTION_STATE_IDLE;

}

static size_t consume_data(amqp_connection_state_t state,

                           amqp_bytes_t *received_data) {

  /* how much data is available and will fit? */

  size_t bytes_consumed = state->target_size - state->inbound_offset;

  if (received_data->len < bytes_consumed) {

    bytes_consumed = received_data->len;

  }

  memcpy(amqp_offset(state->inbound_buffer.bytes, state->inbound_offset),

         received_data->bytes, bytes_consumed);

  state->inbound_offset += bytes_consumed;

  received_data->bytes = amqp_offset(received_data->bytes, bytes_consumed);

  received_data->len -= bytes_consumed;

  return bytes_consumed;

}

int amqp_handle_input(amqp_connection_state_t state, amqp_bytes_t received_data,

                      amqp_frame_t *decoded_frame) {

  size_t bytes_consumed;

  void *raw_frame;

  /* Returning frame_type of zero indicates either insufficient input,

     or a complete, ignored frame was read. */

  decoded_frame->frame_type = 0;

  if (received_data.len == 0) {

    return AMQP_STATUS_OK;

  }

  if (state->state == CONNECTION_STATE_IDLE) {

    state->state = CONNECTION_STATE_HEADER;

  }

  bytes_consumed = consume_data(state, &received_data);

  /* do we have target_size data yet? if not, return with the

     expectation that more will arrive */

  if (state->inbound_offset < state->target_size) {

    return (int)bytes_consumed;

  }

  raw_frame = state->inbound_buffer.bytes;

  switch (state->state) {

    case CONNECTION_STATE_INITIAL:

      /* check for a protocol header from the server */

      if (memcmp(raw_frame, "AMQP", 4) == 0) {

        decoded_frame->frame_type = AMQP_PSEUDOFRAME_PROTOCOL_HEADER;

        decoded_frame->channel = 0;

        decoded_frame->payload.protocol_header.transport_high =

            amqp_d8(amqp_offset(raw_frame, 4));

        decoded_frame->payload.protocol_header.transport_low =

            amqp_d8(amqp_offset(raw_frame, 5));

        decoded_frame->payload.protocol_header.protocol_version_major =

            amqp_d8(amqp_offset(raw_frame, 6));

        decoded_frame->payload.protocol_header.protocol_version_minor =

            amqp_d8(amqp_offset(raw_frame, 7));

        return_to_idle(state);

        return (int)bytes_consumed;

      }

      /* it's not a protocol header; fall through to process it as a

         regular frame header */

    case CONNECTION_STATE_HEADER: {

      amqp_channel_t channel;

      amqp_pool_t *channel_pool;

      uint32_t frame_size;

      channel = amqp_d16(amqp_offset(raw_frame, 1));

      /* frame length is 3 bytes in */

      frame_size = amqp_d32(amqp_offset(raw_frame, 3));

      /* To prevent the target_size calculation below from overflowing, check

       * that the stated frame_size is smaller than a signed 32-bit. Given

       * the library only allows configuring frame_max as an int32_t, and

       * frame_size is uint32_t, the math below is safe from overflow. */

      if (frame_size >= INT32_MAX) {

        return AMQP_STATUS_BAD_AMQP_DATA;

      }

      frame_size = frame_size + HEADER_SIZE + FOOTER_SIZE;

      if ((size_t)state->frame_max < frame_size) {

        return AMQP_STATUS_BAD_AMQP_DATA;

      }

      channel_pool = amqp_get_or_create_channel_pool(state, channel);

      if (NULL == channel_pool) {

        return AMQP_STATUS_NO_MEMORY;

      }

      amqp_pool_alloc_bytes(channel_pool, frame_size, &state->inbound_buffer);

      if (NULL == state->inbound_buffer.bytes) {

        return AMQP_STATUS_NO_MEMORY;

      }

      memcpy(state->inbound_buffer.bytes, state->header_buffer, HEADER_SIZE);

      raw_frame = state->inbound_buffer.bytes;

      state->state = CONNECTION_STATE_BODY;

      state->target_size = frame_size;

      bytes_consumed += consume_data(state, &received_data);

      /* do we have target_size data yet? if not, return with the

         expectation that more will arrive */

      if (state->inbound_offset < state->target_size) {

        return (int)bytes_consumed;

      }

    }

      /* fall through to process body */

    case CONNECTION_STATE_BODY: {

      amqp_bytes_t encoded;

      int res;

      amqp_pool_t *channel_pool;

      /* Check frame end marker (footer) */

      if (amqp_d8(amqp_offset(raw_frame, state->target_size - 1)) !=

          AMQP_FRAME_END) {

        return AMQP_STATUS_BAD_AMQP_DATA;

      }

      decoded_frame->frame_type = amqp_d8(amqp_offset(raw_frame, 0));

      decoded_frame->channel = amqp_d16(amqp_offset(raw_frame, 1));

      channel_pool =

          amqp_get_or_create_channel_pool(state, decoded_frame->channel);

      if (NULL == channel_pool) {

        return AMQP_STATUS_NO_MEMORY;

      }

      switch (decoded_frame->frame_type) {

        case AMQP_FRAME_METHOD:

          decoded_frame->payload.method.id =

              amqp_d32(amqp_offset(raw_frame, HEADER_SIZE));

          encoded.bytes = amqp_offset(raw_frame, HEADER_SIZE + 4);

          encoded.len = state->target_size - HEADER_SIZE - 4 - FOOTER_SIZE;

          res = amqp_decode_method(decoded_frame->payload.method.id,

                                   channel_pool, encoded,

                                   &decoded_frame->payload.method.decoded);

          if (res < 0) {

            return res;

          }

          break;

        case AMQP_FRAME_HEADER:

          decoded_frame->payload.properties.class_id =

              amqp_d16(amqp_offset(raw_frame, HEADER_SIZE));

          /* unused 2-byte weight field goes here */

          decoded_frame->payload.properties.body_size =

              amqp_d64(amqp_offset(raw_frame, HEADER_SIZE + 4));

          encoded.bytes = amqp_offset(raw_frame, HEADER_SIZE + 12);

          encoded.len = state->target_size - HEADER_SIZE - 12 - FOOTER_SIZE;

          decoded_frame->payload.properties.raw = encoded;

          res = amqp_decode_properties(

              decoded_frame->payload.properties.class_id, channel_pool, encoded,

              &decoded_frame->payload.properties.decoded);

          if (res < 0) {

            return res;

          }

          break;

        case AMQP_FRAME_BODY:

          decoded_frame->payload.body_fragment.len =

              state->target_size - HEADER_SIZE - FOOTER_SIZE;

          decoded_frame->payload.body_fragment.bytes =

              amqp_offset(raw_frame, HEADER_SIZE);

          break;

        case AMQP_FRAME_HEARTBEAT:

          break;

        default:

          /* Ignore the frame */

          decoded_frame->frame_type = 0;

          break;

      }

      return_to_idle(state);

      return (int)bytes_consumed;

    }

    default:

      amqp_abort("Internal error: invalid amqp_connection_state_t->state %d",

                 state->state);

  }

}

amqp_boolean_t amqp_release_buffers_ok(amqp_connection_state_t state) {

  return (state->state == CONNECTION_STATE_IDLE);

}

void amqp_release_buffers(amqp_connection_state_t state) {

  int i;

  ENFORCE_STATE(state, CONNECTION_STATE_IDLE);

  for (i = 0; i < POOL_TABLE_SIZE; ++i) {

    amqp_pool_table_entry_t *entry = state->pool_table[i];

    for (; NULL != entry; entry = entry->next) {

      amqp_maybe_release_buffers_on_channel(state, entry->channel);

    }

  }

}

void amqp_maybe_release_buffers(amqp_connection_state_t state) {

  if (amqp_release_buffers_ok(state)) {

    amqp_release_buffers(state);

  }

}

void amqp_maybe_release_buffers_on_channel(amqp_connection_state_t state,

                                           amqp_channel_t channel) {

  amqp_link_t *queued_link;

  amqp_pool_t *pool;

  if (CONNECTION_STATE_IDLE != state->state) {

    return;

  }

  queued_link = state->first_queued_frame;

  while (NULL != queued_link) {

    amqp_frame_t *frame = queued_link->data;

    if (channel == frame->channel) {

      return;

    }

    queued_link = queued_link->next;

  }

  pool = amqp_get_channel_pool(state, channel);

  if (pool != NULL) {

    recycle_amqp_pool(pool);

  }

}

static int amqp_frame_to_bytes(const amqp_frame_t *frame, amqp_bytes_t buffer,

                               amqp_bytes_t *encoded) {

  void *out_frame = buffer.bytes;

  size_t out_frame_len;

  int res;

  amqp_e8(frame->frame_type, amqp_offset(out_frame, 0));

  amqp_e16(frame->channel, amqp_offset(out_frame, 1));

  switch (frame->frame_type) {

    case AMQP_FRAME_BODY: {

      const amqp_bytes_t *body = &frame->payload.body_fragment;

      memcpy(amqp_offset(out_frame, HEADER_SIZE), body->bytes, body->len);

      out_frame_len = body->len;

      break;

    }

    case AMQP_FRAME_METHOD: {

      amqp_bytes_t method_encoded;

      amqp_e32(frame->payload.method.id, amqp_offset(out_frame, HEADER_SIZE));

      method_encoded.bytes = amqp_offset(out_frame, HEADER_SIZE + 4);

      method_encoded.len = buffer.len - HEADER_SIZE - 4 - FOOTER_SIZE;

      res = amqp_encode_method(frame->payload.method.id,

                               frame->payload.method.decoded, method_encoded);

      if (res < 0) {

        return res;

      }

      out_frame_len = res + 4;

      break;

    }

    case AMQP_FRAME_HEADER: {

      amqp_bytes_t properties_encoded;

      amqp_e16(frame->payload.properties.class_id,

               amqp_offset(out_frame, HEADER_SIZE));

      amqp_e16(0, amqp_offset(out_frame, HEADER_SIZE + 2)); /* "weight" */

      amqp_e64(frame->payload.properties.body_size,

               amqp_offset(out_frame, HEADER_SIZE + 4));

      properties_encoded.bytes = amqp_offset(out_frame, HEADER_SIZE + 12);

      properties_encoded.len = buffer.len - HEADER_SIZE - 12 - FOOTER_SIZE;

      res = amqp_encode_properties(frame->payload.properties.class_id,

                                   frame->payload.properties.decoded,

                                   properties_encoded);

      if (res < 0) {

        return res;

      }

      out_frame_len = res + 12;

      break;

    }

    case AMQP_FRAME_HEARTBEAT:

      out_frame_len = 0;

      break;

    default:

      return AMQP_STATUS_INVALID_PARAMETER;

  }

  amqp_e32((uint32_t)out_frame_len, amqp_offset(out_frame, 3));

  amqp_e8(AMQP_FRAME_END, amqp_offset(out_frame, HEADER_SIZE + out_frame_len));

  encoded->bytes = out_frame;

  encoded->len = out_frame_len + HEADER_SIZE + FOOTER_SIZE;

  return AMQP_STATUS_OK;

}

int amqp_send_frame(amqp_connection_state_t state, const amqp_frame_t *frame) {

  return amqp_send_frame_inner(state, frame, AMQP_SF_NONE,

                               amqp_time_infinite());

}

int amqp_send_frame_inner(amqp_connection_state_t state,

                          const amqp_frame_t *frame, int flags,

                          amqp_time_t deadline) {

  int res;

  ssize_t sent;

  amqp_bytes_t encoded;

  amqp_time_t next_timeout;

  /* TODO: if the AMQP_SF_MORE socket optimization can be shown to work

   * correctly, then this could be un-done so that body-frames are sent as 3

   * send calls, getting rid of the copy of the body content, some testing

   * would need to be done to see if this would actually a win for performance.

   * */

  res = amqp_frame_to_bytes(frame, state->outbound_buffer, &encoded);

  if (AMQP_STATUS_OK != res) {

    return res;

  }

start_send:

  next_timeout = amqp_time_first(deadline, state->next_recv_heartbeat);

  sent = amqp_try_send(state, encoded.bytes, encoded.len, next_timeout, flags);

  if (0 > sent) {

    return (int)sent;

  }

  /* A partial send has occurred, because of a heartbeat timeout (so try recv

   * something) or common timeout (so return AMQP_STATUS_TIMEOUT) */

  if ((ssize_t)encoded.len != sent) {

    if (amqp_time_equal(next_timeout, deadline)) {

      /* timeout of method was received, so return from method*/

      return AMQP_STATUS_TIMEOUT;

    }

    res = amqp_try_recv(state);

    if (AMQP_STATUS_TIMEOUT == res) {

      return AMQP_STATUS_HEARTBEAT_TIMEOUT;

    } else if (AMQP_STATUS_OK != res) {

      return res;

    }

    encoded.bytes = (uint8_t *)encoded.bytes + sent;

    encoded.len -= sent;

    goto start_send;

  }

  res = amqp_time_s_from_now(&state->next_send_heartbeat,

                             amqp_heartbeat_send(state));

  return res;

}

amqp_table_t *amqp_get_server_properties(amqp_connection_state_t state) {

  return &state->server_properties;

}

amqp_table_t *amqp_get_client_properties(amqp_connection_state_t state) {

  return &state->client_properties;

}