mysql.c

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/*
     This file is part of GNUnet
     Copyright (C) 2012 GNUnet e.V.

     GNUnet is free software: you can redistribute it and/or modify it
     under the terms of the GNU Affero General Public License as published
     by the Free Software Foundation, either version 3 of the License,
     or (at your option) any later version.

     GNUnet 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.  See the GNU
     Affero General Public License for more details.

     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/>.

     SPDX-License-Identifier: AGPL3.0-or-later
 */
#include "platform.h"
#include <mysql/mysql.h>
#include "gnunet_mysql_lib.h"

#define MAX_PARAM 16


#define DIE_MYSQL(cmd, dbh)                                       \
  do                                                              \
    {                                                               \
      GNUNET_log_from(GNUNET_ERROR_TYPE_ERROR,                     \
                      "mysql",                                     \
                      _("`%s' failed at %s:%d with error: %s\n"), \
                      cmd,                                         \
                      __FILE__,                                    \
                      __LINE__,                                    \
                      mysql_error((dbh)->dbf));                   \
      GNUNET_assert(0);                                            \
    } while (0);

#define LOG_MYSQL(level, cmd, dbh)                                \
  do                                                              \
    {                                                               \
      GNUNET_log_from(level,                                       \
                      "mysql",                                     \
                      _("`%s' failed at %s:%d with error: %s\n"), \
                      cmd,                                         \
                      __FILE__,                                    \
                      __LINE__,                                    \
                      mysql_error((dbh)->dbf));                   \
    } while (0);


struct GNUNET_MYSQL_Context {
  const struct GNUNET_CONFIGURATION_Handle *cfg;

  const char *section;

  MYSQL *dbf;

  struct GNUNET_MYSQL_StatementHandle *shead;

  struct GNUNET_MYSQL_StatementHandle *stail;

  char *cnffile;
};


struct GNUNET_MYSQL_StatementHandle {
  struct GNUNET_MYSQL_StatementHandle *next;

  struct GNUNET_MYSQL_StatementHandle *prev;

  struct GNUNET_MYSQL_Context *mc;

  char *query;

  MYSQL_STMT *statement;

  int valid;
};


static char *
get_my_cnf_path(const struct GNUNET_CONFIGURATION_Handle *cfg,
                const char *section)
{
  char *cnffile;
  char *home_dir;
  struct stat st;

  struct passwd *pw;

  int configured;

  pw = getpwuid(getuid());
  if (!pw)
    {
      GNUNET_log_from_strerror(GNUNET_ERROR_TYPE_ERROR, "mysql", "getpwuid");
      return NULL;
    }
  if (GNUNET_YES == GNUNET_CONFIGURATION_have_value(cfg, section, "CONFIG"))
    {
      GNUNET_assert(GNUNET_OK ==
                    GNUNET_CONFIGURATION_get_value_filename(cfg,
                                                            section,
                                                            "CONFIG",
                                                            &cnffile));
      configured = GNUNET_YES;
    }
  else
    {
      home_dir = GNUNET_strdup(pw->pw_dir);
      GNUNET_asprintf(&cnffile, "%s/.my.cnf", home_dir);
      GNUNET_free(home_dir);
      configured = GNUNET_NO;
    }

  GNUNET_log_from(GNUNET_ERROR_TYPE_INFO,
                  "mysql",
                  _("Trying to use file `%s' for MySQL configuration.\n"),
                  cnffile);
  if ((0 != stat(cnffile, &st)) || (0 != access(cnffile, R_OK)) ||
      (!S_ISREG(st.st_mode)))
    {
      if (configured == GNUNET_YES)
        GNUNET_log_from(GNUNET_ERROR_TYPE_ERROR,
                        "mysql",
                        _("Could not access file `%s': %s\n"),
                        cnffile,
                        strerror(errno));
      GNUNET_free(cnffile);
      return NULL;
    }
  return cnffile;
}


static int
iopen(struct GNUNET_MYSQL_Context *mc)
{
  char *mysql_dbname;
  char *mysql_server;
  char *mysql_user;
  char *mysql_password;
  unsigned long long mysql_port;
  my_bool reconnect;
  unsigned int timeout;

  mc->dbf = mysql_init(NULL);
  if (mc->dbf == NULL)
    return GNUNET_SYSERR;
  if (mc->cnffile != NULL)
    mysql_options(mc->dbf, MYSQL_READ_DEFAULT_FILE, mc->cnffile);
  mysql_options(mc->dbf, MYSQL_READ_DEFAULT_GROUP, "client");
  reconnect = 0;
  mysql_options(mc->dbf, MYSQL_OPT_RECONNECT, &reconnect);
  mysql_options(mc->dbf, MYSQL_OPT_CONNECT_TIMEOUT, (const void *)&timeout);
  mysql_options(mc->dbf, MYSQL_SET_CHARSET_NAME, "UTF8");
  timeout = 60; /* in seconds */
  mysql_options(mc->dbf, MYSQL_OPT_READ_TIMEOUT, (const void *)&timeout);
  mysql_options(mc->dbf, MYSQL_OPT_WRITE_TIMEOUT, (const void *)&timeout);
  mysql_dbname = NULL;
  if (GNUNET_YES ==
      GNUNET_CONFIGURATION_have_value(mc->cfg, mc->section, "DATABASE"))
    GNUNET_assert(GNUNET_OK ==
                  GNUNET_CONFIGURATION_get_value_string(mc->cfg,
                                                        mc->section,
                                                        "DATABASE",
                                                        &mysql_dbname));
  else
    mysql_dbname = GNUNET_strdup("gnunet");
  mysql_user = NULL;
  if (GNUNET_YES ==
      GNUNET_CONFIGURATION_have_value(mc->cfg, mc->section, "USER"))
    {
      GNUNET_assert(GNUNET_OK ==
                    GNUNET_CONFIGURATION_get_value_string(mc->cfg,
                                                          mc->section,
                                                          "USER",
                                                          &mysql_user));
    }
  mysql_password = NULL;
  if (GNUNET_YES ==
      GNUNET_CONFIGURATION_have_value(mc->cfg, mc->section, "PASSWORD"))
    {
      GNUNET_assert(GNUNET_OK ==
                    GNUNET_CONFIGURATION_get_value_string(mc->cfg,
                                                          mc->section,
                                                          "PASSWORD",
                                                          &mysql_password));
    }
  mysql_server = NULL;
  if (GNUNET_YES ==
      GNUNET_CONFIGURATION_have_value(mc->cfg, mc->section, "HOST"))
    {
      GNUNET_assert(GNUNET_OK ==
                    GNUNET_CONFIGURATION_get_value_string(mc->cfg,
                                                          mc->section,
                                                          "HOST",
                                                          &mysql_server));
    }
  mysql_port = 0;
  if (GNUNET_YES ==
      GNUNET_CONFIGURATION_have_value(mc->cfg, mc->section, "PORT"))
    {
      GNUNET_assert(GNUNET_OK ==
                    GNUNET_CONFIGURATION_get_value_number(mc->cfg,
                                                          mc->section,
                                                          "PORT",
                                                          &mysql_port));
    }

  GNUNET_assert(mysql_dbname != NULL);
  mysql_real_connect(mc->dbf,
                     mysql_server,
                     mysql_user,
                     mysql_password,
                     mysql_dbname,
                     (unsigned int)mysql_port,
                     NULL,
                     CLIENT_IGNORE_SIGPIPE);
  GNUNET_free_non_null(mysql_server);
  GNUNET_free_non_null(mysql_user);
  GNUNET_free_non_null(mysql_password);
  GNUNET_free(mysql_dbname);
  if (mysql_error(mc->dbf)[0])
    {
      LOG_MYSQL(GNUNET_ERROR_TYPE_ERROR, "mysql_real_connect", mc);
      return GNUNET_SYSERR;
    }
  return GNUNET_OK;
}


struct GNUNET_MYSQL_Context *
GNUNET_MYSQL_context_create(const struct GNUNET_CONFIGURATION_Handle *cfg,
                            const char *section)
{
  struct GNUNET_MYSQL_Context *mc;

  mc = GNUNET_new(struct GNUNET_MYSQL_Context);
  mc->cfg = cfg;
  mc->section = section;
  mc->cnffile = get_my_cnf_path(cfg, section);

  return mc;
}


void
GNUNET_MYSQL_statements_invalidate(struct GNUNET_MYSQL_Context *mc)
{
  struct GNUNET_MYSQL_StatementHandle *sh;

  for (sh = mc->shead; NULL != sh; sh = sh->next)
    {
      if (GNUNET_YES == sh->valid)
        {
          mysql_stmt_close(sh->statement);
          sh->valid = GNUNET_NO;
        }
      sh->statement = NULL;
    }
  if (NULL != mc->dbf)
    {
      mysql_close(mc->dbf);
      mc->dbf = NULL;
    }
}


void
GNUNET_MYSQL_context_destroy(struct GNUNET_MYSQL_Context *mc)
{
  struct GNUNET_MYSQL_StatementHandle *sh;

  GNUNET_MYSQL_statements_invalidate(mc);
  while (NULL != (sh = mc->shead))
    {
      GNUNET_CONTAINER_DLL_remove(mc->shead, mc->stail, sh);
      GNUNET_free(sh->query);
      GNUNET_free(sh);
    }
  GNUNET_free(mc);
  mysql_library_end();
}


struct GNUNET_MYSQL_StatementHandle *
GNUNET_MYSQL_statement_prepare(struct GNUNET_MYSQL_Context *mc,
                               const char *query)
{
  struct GNUNET_MYSQL_StatementHandle *sh;

  sh = GNUNET_new(struct GNUNET_MYSQL_StatementHandle);
  sh->mc = mc;
  sh->query = GNUNET_strdup(query);
  GNUNET_CONTAINER_DLL_insert(mc->shead, mc->stail, sh);
  return sh;
}


int
GNUNET_MYSQL_statement_run(struct GNUNET_MYSQL_Context *mc, const char *sql)
{
  if ((NULL == mc->dbf) && (GNUNET_OK != iopen(mc)))
    return GNUNET_SYSERR;
  mysql_query(mc->dbf, sql);
  if (mysql_error(mc->dbf)[0])
    {
      LOG_MYSQL(GNUNET_ERROR_TYPE_ERROR, "mysql_query", mc);
      GNUNET_MYSQL_statements_invalidate(mc);
      return GNUNET_SYSERR;
    }
  return GNUNET_OK;
}


static int
prepare_statement(struct GNUNET_MYSQL_StatementHandle *sh)
{
  struct GNUNET_MYSQL_Context *mc = sh->mc;

  if (GNUNET_YES == sh->valid)
    return GNUNET_OK;
  if ((NULL == mc->dbf) && (GNUNET_OK != iopen(mc)))
    return GNUNET_SYSERR;
  sh->statement = mysql_stmt_init(mc->dbf);
  if (NULL == sh->statement)
    {
      GNUNET_MYSQL_statements_invalidate(mc);
      return GNUNET_SYSERR;
    }
  if (0 != mysql_stmt_prepare(sh->statement, sh->query, strlen(sh->query)))
    {
      GNUNET_log_from(GNUNET_ERROR_TYPE_ERROR,
                      "mysql",
                      "prepare_statement: %s\n",
                      sh->query);
      LOG_MYSQL(GNUNET_ERROR_TYPE_ERROR, "mysql_stmt_prepare", mc);
      mysql_stmt_close(sh->statement);
      sh->statement = NULL;
      GNUNET_MYSQL_statements_invalidate(mc);
      return GNUNET_SYSERR;
    }
  sh->valid = GNUNET_YES;
  return GNUNET_OK;
}


MYSQL_STMT *
GNUNET_MYSQL_statement_get_stmt(struct GNUNET_MYSQL_StatementHandle *sh)
{
  (void)prepare_statement(sh);
  return sh->statement;
}


/* end of mysql.c */