TimJTi commented on code in PR #2228: URL: https://github.com/apache/nuttx-apps/pull/2228#discussion_r1424266413
########## system/settings/storage_eeprom.c: ########## @@ -0,0 +1,408 @@ +/**************************************************************************** + * apps/system/settings/storage_eeprom.c + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. The + * ASF licenses this file to you 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. + * + ****************************************************************************/ + +/**************************************************************************** + * + * The EEPROM storage is similar to the binary type, but only saves out + * values if they've actually changed, to maximise device life. + * + * It can, of course, be used with other storage media types that have + * limited write cycle capabilities. + * + * RE-VISIT IN FUTURE - This could be enhanced by allowing for variable + * storage sizes, but gets complicated if the settings type, and hence size, + * changes as settings after the saved storage will need to move/change. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include "system/settings.h" +#include <unistd.h> +#include <errno.h> +#include <assert.h> +#include <fcntl.h> +#include <nuttx/crc32.h> +#include <stdlib.h> +#include <string.h> +#include <stdint.h> +#include <nuttx/config.h> +#include <sys/types.h> + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Types + ****************************************************************************/ + +/**************************************************************************** + * Private Function Prototypes + ****************************************************************************/ + +FAR static setting_t *getsetting(char *key); +size_t getsettingsize(enum settings_type_e type); + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +static size_t used_storage; + +/**************************************************************************** + * Public Data + ****************************************************************************/ + +extern setting_t map[CONFIG_SYSTEM_SETTINGS_MAP_SIZE]; + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: getsetting + * + * Description: + * Gets the setting information from a given key. + * + * Input Parameters: + * key - key of the required setting + * + * Returned Value: + * The setting + * + ****************************************************************************/ + +FAR setting_t *getsetting(FAR char *key) +{ + int i; + + for (i = 0; i < CONFIG_SYSTEM_SETTINGS_MAP_SIZE; i++) + { + FAR setting_t *setting = &map[i]; + + if (strcmp(key, setting->key) == 0) + { + return setting; + } + + if (setting->type == SETTING_EMPTY) + { + return setting; + } + } + + return NULL; +} + +/**************************************************************************** + * Name: getsettingsize + * + * Description: + * Helper function to gets the size of the setting type for a given type. + * + * Input Parameters: + * type - the type to get the size of + * + * Returned Value: + * The setting + * + ****************************************************************************/ + +size_t getsettingsize(enum settings_type_e type) +{ + switch (type) + { + case SETTING_STRING: + { + return CONFIG_SYSTEM_SETTINGS_VALUE_SIZE * (sizeof(char)); + } + break; + case SETTING_BOOL: + { + return sizeof(bool); + } + break; + case SETTING_INT: + { + return sizeof(int); + } + break; + case SETTING_BYTE: + { + return sizeof(uint8_t); + } + break; + case SETTING_FLOAT: + { + return sizeof(float); + } + break; + case SETTING_IP_ADDR: + { + return sizeof(struct in_addr); + } + break; + case SETTING_EMPTY: + default: + { + return 0; + } + break; + } +} + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: load_eeprom + * + * Description: + * Loads binary data from an EEPROM storage file. + * + * Input Parameters: + * file - the filename of the storage to use + * + * Returned Value: + * Success or negated failure code + * + ****************************************************************************/ + +int load_eeprom(FAR char *file) +{ + int fd; + int i; + int ret = OK; + uint16_t valid; + uint16_t count; + uint32_t calc_crc = 0; + uint32_t exp_crc = 0; + setting_t setting; + FAR setting_t *slot; + size_t size; + + fd = open(file, O_RDONLY); + if (fd < 0) + { + return -ENOENT; + } + + used_storage = 0; + valid = 0; + read(fd, &valid, sizeof(valid)); + + if (valid != VALID) + { + ret = -EBADMSG; + goto abort; /* Just exit - the settings aren't valid */ + } + + count = 0; + read(fd, &count, sizeof(count)); + + /* check storage integrity using crc check */ + + for (i = 0; i < count; i++) + { + read(fd, &setting.key, CONFIG_SYSTEM_SETTINGS_KEY_SIZE); + read(fd, &setting.type, sizeof(uint16_t)); + size = getsettingsize(setting.type); + read(fd, &setting.val, size); + size += (CONFIG_SYSTEM_SETTINGS_KEY_SIZE + sizeof(uint16_t)); + calc_crc = crc32part((FAR uint8_t *)&setting, size, calc_crc); + } + + lseek(fd, 0, SEEK_CUR); + read(fd, &exp_crc, sizeof(exp_crc)); + if (calc_crc != exp_crc) + { + ret = -EBADMSG; + goto abort; + } + + lseek(fd, (sizeof(count) + sizeof(valid)), SEEK_SET); + + used_storage = sizeof(valid) + sizeof(count) + sizeof(calc_crc); + + for (i = 0; i < count; i++) + { + read(fd, &setting.key, CONFIG_SYSTEM_SETTINGS_KEY_SIZE); + read(fd, &setting.type, sizeof(uint16_t)); + size = getsettingsize(setting.type); + read(fd, &setting.val, size); + slot = getsetting(setting.key); + if (slot == NULL) + { + continue; + } + + size += (CONFIG_SYSTEM_SETTINGS_KEY_SIZE + sizeof(uint16_t)); + used_storage += size; + memcpy(slot, &setting, size); + } + +abort: + close(fd); + return ret; +} + +/**************************************************************************** + * Name: save_eeprom + * + * Description: + * Saves binary data to an EEPROM storage file. + * The first two stored values are: + * 1) "valid" - set to a "magic" number when store is valid + * 2) "count" - the number of settings in the store + * At the end of the store a crc is saved of all settings data (excluding + * "valid and "count") + * + * Input Parameters: + * file - the filename of the storage to use + * + * Returned Value: + * Success or negated failure code + * + ****************************************************************************/ + +int save_eeprom(FAR char *file) +{ + uint16_t valid = 0; + uint16_t count = 0; + uint16_t eeprom_cnt; + int fd; + int ret = OK; + int i; + uint32_t crc = 0; + setting_t old_setting; + setting_t new_setting; + size_t new_size; + size_t old_size; + + /* How many settings do we have? */ + + for (i = 0; i < CONFIG_SYSTEM_SETTINGS_MAP_SIZE; i++) + { + if (map[i].type == SETTING_EMPTY) + { + break; + } + + count++; + } + + used_storage = 0; + fd = open(file, (O_RDWR | O_TRUNC), 0666); + if (fd < 0) + { + ret = -ENODEV; + return ret; + } + + read(fd, &valid, sizeof(valid)); + eeprom_cnt = 0; + read(fd, &eeprom_cnt, sizeof(eeprom_cnt)); + + for (i = 0; i < count; i++) + { + new_setting = map[i]; + new_size = getsettingsize(new_setting.type); + new_size += CONFIG_SYSTEM_SETTINGS_KEY_SIZE + sizeof(uint16_t); + read(fd, &old_setting.key, CONFIG_SYSTEM_SETTINGS_KEY_SIZE); + read(fd, &old_setting.type, sizeof(uint16_t)); + old_size = getsettingsize(old_setting.type); + read(fd, &old_setting.val, old_size); + old_size += (CONFIG_SYSTEM_SETTINGS_KEY_SIZE + sizeof(uint16_t)); + if ((i < eeprom_cnt) && (new_size > old_size)) + { + /* We can only change /existing/ type if the size is no larger. Review Comment: I will think about this for sure, but I was trying to avoid rewriting lots of data unless we really had to simply because EEPROM is slow. It perhaps depends on whether users are really likely to change a setting type on the fly? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: commits-unsubscr...@nuttx.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
