int pool_get_config(char *confpath, POOL_CONFIG_CONTEXT context){      ......                                #define PARSE_ERROR()             pool_error("pool_config: parse error at line %d '%s'", Lineno, yytext)                                              /* open config file */                                        fd = fopen(confpath, "r");                                        if (!fd){                                        fprintf(stderr, "pool_config: could not open configuration file (%s)\n", POOL_CONF_FILE_NAME);                            fprintf(stderr, "pool_config: using default values...\n"); return 0;                                    }                                        yyin = fd;                                        Lineno = 1;                                        for(;;)                                        {                                        token = yylex();                                    if (token == 0){                                    break;                                  }                                    if (token == POOL_PARSE_ERROR){                                    PARSE_ERROR();                                fclose(fd);                                return(-1);                                }                                    if (token == POOL_EOL)                                    continue;                                if (token != POOL_KEY){                                    PARSE_ERROR();                                fclose(fd);                                return(-1);                                }                                    ……                                    if (!strcmp(key, "allow_inet_domain_socket") &&              CHECK_CONTEXT(INIT_CONFIG, context)){ ……                                }                                    else if (!strcmp(key, "listen_addresses") &&             CHECK_CONTEXT(INIT_CONFIG, context)){ char *str;                     if (token != POOL_STRING && token != POOL_UNQUOTED_STRING &&                    token != POOL_KEY){                                PARSE_ERROR();                            fclose(fd);                            return(-1);                            }                                str = extract_string(yytext, token);                                if (str == NULL){                                fclose(fd);                            return(-1);                            }                                pool_config->listen_addresses = str;                                }                                    ……                                  else if (!strncmp(key, "backend_hostname", 16) &&CHECK_CONTEXT(INIT_CONFIG|RELOAD_CONFIG, context) && mypid == getpid())                    /* this parameter must be modified by parent pid */                            {                                    int slot;                                char *str;                    slot = atoi(key + 16);                                if (slot < 0 || slot >= MAX_CONNECTION_SLOTS){                                pool_error("pool_config:                      backend number %s for backend_hostname out of range", key);fclose(fd);                            return(-1);                            }                                str = extract_string(yytext, token);                                if (str == NULL){                                fclose(fd);                            return(-1);                            }                                if (context == INIT_CONFIG || (context == RELOAD_CONFIG &&                  BACKEND_INFO(slot).backend_status == CON_UNUSED)) strncpy(BACKEND_INFO(slot).backend_hostname, str,                        MAX_DB_HOST_NAMELEN);                            }                                  ……                                    else if (!strcmp(key, "relcache_expire") &&               CHECK_CONTEXT(INIT_CONFIG|RELOAD_CONFIG, context)){ int v = atoi(yytext);          if (token != POOL_INTEGER || v < 0){                                pool_error("pool_config: %s                      must be equal or higher than 0 numeric value", key);                          fclose(fd);                            return(-1);                            }                                pool_config->relcache_expire = v;                                }                                 }                                        fclose(fd);                            ……                                        return 0;
}                                            

static char *extract_string(char *value, POOL_TOKEN token){                        char *ret;          ret = strdup(value);                    if (!ret){                    pool_error("extract_string: out of memory");                return NULL;                }                    if (token == POOL_STRING){                    ret[strlen(ret)-1] = '\0';                return (ret+1);                }                    return ret;
}