generator.c

/* 
 * Copyright (C) 2009 Toru Maesaka <dev@torum.net>
 * All Rights Reserved.
 *
 * Use and distribution of this program is licensed under the
 * BSD license. See the COPYING file for full text.
 */

#include "generator.h"

static uint32_t next_id(SKY_WORKER *worker, uint32_t col_num) {
  assert(worker);
  return worker->current_seq_id[col_num] += worker->share->concurrency;
}

/* Read a given file and create a list with it's contents */
static SKY_LIST *load_file_to_list(const char *path) {
  SKY_LIST *list;
  FILE *sql_file;
  char buffer[SKY_STRSIZ];
  int num_loaded = 0;

  /* open the SQL file */
  if (!(sql_file = fopen(path, "r"))) {
    report_error("failed to open the specified SQL file");
    return NULL;
  }  

  /* allocate memory to the provided list pointer */
  if ((list = sky_list_new()) == NULL) {
    fclose(sql_file);
    return NULL;
  }

  /* push all queries found to the list */
  while (fgets(buffer, SKY_STRSIZ, sql_file) != NULL &&
         num_loaded != MAX_LOADABLE_QUERIES) {
    size_t query_len = strlen(buffer);

    if (buffer[query_len-1] == '\n') {
      buffer[query_len-1] = '\0';
      query_len--;
    }

    if (!query_len) 
      continue;

    if (!sky_list_push(list, buffer, query_len)) {
      sky_list_free(list);
      fclose(sql_file);
      return NULL;
    }
    num_loaded++;
  }

  fclose(sql_file);
  return list;
}

size_t next_insert_query(SKY_WORKER *worker, char *buffer, size_t buflen) {
  size_t query_length;  
  char *pos, *write_ptr;

  /* copy everything up to the values. e.g. 'INSERT INTO t1 VALUES (' */
  write_ptr = buffer;
  pos = strchr(worker->share->insert_tmpl, SKY_PLACEHOLDER_SYM);
  query_length = 0;

  if (pos == NULL)
    return 0;

  size_t temp = pos - worker->share->insert_tmpl;
  size_t free_space = buflen - temp;

  if (temp > SKY_STRSIZ) {
    report_error("supplied INSERT query template is too long");
    return 0;
  }

  strncpy(write_ptr, worker->share->insert_tmpl, temp);
  write_ptr += temp;
  query_length += temp;

  /* rewind 1 byte so that the loop below can find the first placeholder */
  pos--; 

  /* now we look for placeholders and generate values for it */
  for (int i = 0; i < worker->share->columns; i++) {
    pos = strchr(pos, SKY_PLACEHOLDER_SYM);

    if (pos == NULL) {
      report_error("invalid INSERT query template");
      return 0;
    }

    if (strncmp(pos, PLACEHOLDER_RAND, PLACEHOLDER_RAND_LEN) == 0) {
      temp = snprintf(write_ptr, free_space, "\"%ld\",",
                      (random() % DEFAULT_RAND_MOD) + 1);
      pos += PLACEHOLDER_RAND_LEN;
    } else if (strncmp(pos, PLACEHOLDER_SEQ, PLACEHOLDER_SEQ_LEN) == 0) {
      temp = snprintf(write_ptr, free_space, "\"%d\",", next_id(worker, i));
      pos += PLACEHOLDER_SEQ_LEN;
    } else {
      return 0;
    }

    write_ptr += temp;
    query_length += temp;
    free_space -= temp;
  }

  /* rewind 1 byte to ignore the final comma */
  write_ptr--;

  /* copy everything up to the end of the statement */
  strncpy(write_ptr, pos, buflen-query_length);
  return query_length;
}

bool preload_sql_file(SKY_SHARE *share) {
  assert(share);

  if (share->read_file_path) {
    share->read_queries = load_file_to_list(share->read_file_path);
    if (share->read_queries == NULL)
      return false;
  }

  if (share->load_file_path) {
    share->load_queries = load_file_to_list(share->load_file_path);
    if (share->load_queries == NULL)
      return false;
  }
  return true;
}