Converted EEPROM library to use nvs instead of partition. (#2678)

* Converted EEPROM library to use nvs instead of partition.  Removed eeprom partition from all partition table CSV files.
* Changed variable names, added some comments, formatting as per me-no-dev's requests
* Checks for memory on malloc
* Moved include nvs.h from header to code
* Reworked the extra example to make it more clear how to actually use the library and persist data

libraries/EEPROM/README.md

+## EEPROM
+
+EEPROM is deprecated.  For new applications on ESP32, use Preferences.  EEPROM is provided for backwards compatibility with existing Arduino applications.
+EEPROM is implemented using a single blob within NVS, so it is a container within a container. As such, it is not going to be a high performance storage method.  Preferences will directly use nvs, and store each entry as a single object therein.

libraries/EEPROM/examples/eeprom_class/eeprom_class.ino

@@ -26,8 +26,8 @@
 #include "EEPROM.h"
 
 // Instantiate eeprom objects with parameter/argument names and size same as in the partition table
-EEPROMClass  NAMES("eeprom0", 0x1000);
-EEPROMClass  HEIGHT("eeprom1", 0x500);
+EEPROMClass  NAMES("eeprom0", 0x500);
+EEPROMClass  HEIGHT("eeprom1", 0x200);
 EEPROMClass  AGE("eeprom2", 0x100);
 
 void setup() {

libraries/EEPROM/examples/eeprom_extra/eeprom_extra.ino

@@ -13,75 +13,124 @@ void setup() {
   // put your setup code here, to run once:
   Serial.begin(115200);
   Serial.println("\nTesting EEPROM Library\n");
-  if (!EEPROM.begin(EEPROM.length())) {
+  if (!EEPROM.begin(1000)) {
     Serial.println("Failed to initialise EEPROM");
     Serial.println("Restarting...");
     delay(1000);
     ESP.restart();
   }
 
-  int address = 0;                                  // Same address is used through the example
+  int address = 0;
 
   EEPROM.writeByte(address, -128);                  // -2^7
-  Serial.println(EEPROM.readByte(address));
+  address += sizeof(byte);
 
   EEPROM.writeChar(address, 'A');                   // Same as writyByte and readByte
-  Serial.println(char(EEPROM.readChar(address)));
+  address += sizeof(char);
 
   EEPROM.writeUChar(address, 255);                  // 2^8 - 1
-  Serial.println(EEPROM.readUChar(address));
+  address += sizeof(unsigned char);
 
   EEPROM.writeShort(address, -32768);               // -2^15
-  Serial.println(EEPROM.readShort(address));
+  address += sizeof(short);
 
   EEPROM.writeUShort(address, 65535);               // 2^16 - 1
-  Serial.println(EEPROM.readUShort(address));
+  address += sizeof(unsigned short);
 
   EEPROM.writeInt(address, -2147483648);            // -2^31
-  Serial.println(EEPROM.readInt(address));
+  address += sizeof(int);
 
   EEPROM.writeUInt(address, 4294967295);            // 2^32 - 1
-  Serial.println(EEPROM.readUInt(address));
+  address += sizeof(unsigned int);
 
   EEPROM.writeLong(address, -2147483648);           // Same as writeInt and readInt
-  Serial.println(EEPROM.readLong(address));
+  address += sizeof(long);
 
   EEPROM.writeULong(address, 4294967295);           // Same as writeUInt and readUInt
-  Serial.println(EEPROM.readULong(address));
+  address += sizeof(unsigned long);
 
   int64_t value = -9223372036854775808;             // -2^63
   EEPROM.writeLong64(address, value);
-  value = 0;                                        // Clear value
+  address += sizeof(int64_t);
+
+  uint64_t  Value = 18446744073709551615;           // 2^64 - 1
+  EEPROM.writeULong64(address, Value);
+  address += sizeof(uint64_t);
+
+  EEPROM.writeFloat(address, 1234.1234);
+  address += sizeof(float);
+
+  EEPROM.writeDouble(address, 123456789.123456789);
+  address += sizeof(double);
+
+  EEPROM.writeBool(address, true);
+  address += sizeof(bool);
+
+  String sentence = "I love ESP32.";
+  EEPROM.writeString(address, sentence);
+  address += sentence.length() + 1;
+
+  char gratitude[21] = "Thank You Espressif!";
+  EEPROM.writeString(address, gratitude);
+  address += 21;
+
+  // See also the general purpose writeBytes() and readBytes() for BLOB in EEPROM library
+  EEPROM.commit();
+  address = 0;
+  
+  Serial.println(EEPROM.readByte(address));
+  address += sizeof(byte);
+
+  Serial.println((char)EEPROM.readChar(address));
+  address += sizeof(char);
+
+  Serial.println(EEPROM.readUChar(address));
+  address += sizeof(unsigned char);
+
+  Serial.println(EEPROM.readShort(address));
+  address += sizeof(short);
+
+  Serial.println(EEPROM.readUShort(address));
+  address += sizeof(unsigned short);
+
+  Serial.println(EEPROM.readInt(address));
+  address += sizeof(int);
+
+  Serial.println(EEPROM.readUInt(address));
+  address += sizeof(unsigned int);
+
+  Serial.println(EEPROM.readLong(address));
+  address += sizeof(long);
+
+  Serial.println(EEPROM.readULong(address));
+  address += sizeof(unsigned long);
+
+  value = 0;
   value = EEPROM.readLong64(value);
   Serial.printf("0x%08X", (uint32_t)(value >> 32)); // Print High 4 bytes in HEX
   Serial.printf("%08X\n", (uint32_t)value);         // Print Low 4 bytes in HEX
+  address += sizeof(int64_t);
 
-  uint64_t  Value = 18446744073709551615;           // 2^64 - 1
-  EEPROM.writeULong64(address, Value);
   Value = 0;                                        // Clear Value
   Value = EEPROM.readULong64(Value);
   Serial.printf("0x%08X", (uint32_t)(Value >> 32)); // Print High 4 bytes in HEX
   Serial.printf("%08X\n", (uint32_t)Value);         // Print Low 4 bytes in HEX
+  address += sizeof(uint64_t);
 
-  EEPROM.writeFloat(address, 1234.1234);
   Serial.println(EEPROM.readFloat(address), 4);
+  address += sizeof(float);
 
-  EEPROM.writeDouble(address, 123456789.123456789);
   Serial.println(EEPROM.readDouble(address), 8);
+  address += sizeof(double);
 
-  EEPROM.writeBool(address, true);
   Serial.println(EEPROM.readBool(address));
+  address += sizeof(bool);
 
-  String sentence = "I love ESP32.";
-  EEPROM.writeString(address, sentence);
   Serial.println(EEPROM.readString(address));
+  address += sentence.length() + 1;
 
-  char gratitude[] = "Thank You Espressif!";
-  EEPROM.writeString(address, gratitude);
   Serial.println(EEPROM.readString(address));
-
-  // See also the general purpose writeBytes() and readBytes() for BLOB in EEPROM library
-  // To avoid data overwrite, next address should be chosen/offset by using "address =+ sizeof(previousData)"
+  address += 21;
 }
 
 void loop() {

libraries/EEPROM/src/EEPROM.cpp

 /*
   EEPROM.h -ported by Paolo Becchi to Esp32 from esp8266 EEPROM
            -Modified by Elochukwu Ifediora <ifedioraelochukwuc@gmail.com>
+           -Converted to nvs lbernstone@gmail.com
 
-  Uses a one sector flash partition defined in partition table
-  OR
-  Multiple sector flash partitions defined by the name column in the partition table
+  Uses a nvs byte array to emulate EEPROM
 
   Copyright (c) 2014 Ivan Grokhotkov. All rights reserved.
   This file is part of the esp8266 core for Arduino environment.
@@ -25,39 +24,37 @@
 */
 
 #include "EEPROM.h"
-
+#include <nvs.h>
 #include <esp_log.h>
 
-EEPROMClass::EEPROMClass(uint32_t sector)
-  : _sector(sector)
-  , _data(0)
+EEPROMClass::EEPROMClass(void)
+  : _data(0)
   , _size(0)
   , _dirty(false)
-  , _mypart(NULL)
+  , _handle(NULL)
   , _name("eeprom")
   , _user_defined_size(0)
 {
 }
 
-EEPROMClass::EEPROMClass(const char* name, uint32_t user_defined_size)
-  : _sector(0)
-  , _data(0)
+EEPROMClass::EEPROMClass(uint32_t sector)
+// Only for compatiility, no sectors in nvs!
+  : _data(0)
   , _size(0)
   , _dirty(false)
-  , _mypart(NULL)
-  , _name(name)
-  , _user_defined_size(user_defined_size)
+  , _handle(NULL)
+  , _name("eeprom")
+  , _user_defined_size(0)
 {
 }
 
-EEPROMClass::EEPROMClass(void)
-  : _sector(0)// (((uint32_t)&_SPIFFS_end - 0x40200000) / SPI_FLASH_SEC_SIZE))
-  , _data(0)
+EEPROMClass::EEPROMClass(const char* name, uint32_t user_defined_size)
+  : _data(0)
   , _size(0)
   , _dirty(false)
-  , _mypart(NULL)
-  , _name("eeprom")
-  , _user_defined_size(0)
+  , _handle(NULL)
+  , _name(name)
+  , _user_defined_size(user_defined_size)
 {
 }
 
@@ -66,31 +63,76 @@ EEPROMClass::~EEPROMClass() {
 }
 
 bool EEPROMClass::begin(size_t size) {
-  if (size <= 0) {
+  if (!size) {
+      return false;
+  }
+
+  esp_err_t res = nvs_open(_name, NVS_READWRITE, &_handle);
+  if (res != ESP_OK) {
+      log_e("Unable to open NVS namespace: %d", res);
+      return false;
+  }
+
+  size_t key_size = 0;
+  res = nvs_get_blob(_handle, _name, NULL, &key_size);
+  if(res != ESP_OK && res != ESP_ERR_NVS_NOT_FOUND) {
+      log_e("Unable to read NVS key: %d", res);
+      return false;
+  }
+  if (size < key_size) { // truncate
+      log_w("truncating EEPROM from %d to %d", key_size, size);
+      uint8_t* key_data = (uint8_t*) malloc(key_size);
+      if(!key_data) {
+         log_e("Not enough memory to truncate EEPROM!");
          return false;
       }
-  if (size > SPI_FLASH_SEC_SIZE) {
-    size = SPI_FLASH_SEC_SIZE;
+      nvs_get_blob(_handle, _name, key_data, &key_size);
+      nvs_set_blob(_handle, _name, key_data, size);
+      nvs_commit(_handle);
+      free(key_data);
+  }
+  else if (size > key_size) { // expand or new
+      size_t expand_size = size - key_size;
+      uint8_t* expand_key = (uint8_t*) malloc(expand_size);
+      if(!expand_key) {
+         log_e("Not enough memory to expand EEPROM!");
+         return false;
       }
-  //  _mypart = esp_partition_find_first(ESP_PARTITION_TYPE_DATA,ESP_PARTITION_SUBTYPE_ANY, EEPROM_FLASH_PARTITION_NAME);
-  _mypart = esp_partition_find_first(ESP_PARTITION_TYPE_DATA, ESP_PARTITION_SUBTYPE_ANY, _name);
-  if (_mypart == NULL) {
+      // check for adequate free space
+      if(nvs_set_blob(_handle, "expand", expand_key, expand_size)) {
+        log_e("Not enough space to expand EEPROM from %d to %d", key_size, size);
+        free(expand_key);
         return false;
       }
-  size = (size + 3) & (~3);
+      free(expand_key);
+      nvs_erase_key(_handle, "expand");
+      uint8_t* key_data = (uint8_t*) malloc(size);
+      if(!key_data) {
+         log_e("Not enough memory to expand EEPROM!");
+         return false;
+      }
+      memset(key_data, 0, size);
+      if(key_size) {
+        log_i("Expanding EEPROM from %d to %d", key_size, size);
+	// hold data while key is deleted
+        nvs_get_blob(_handle, _name, key_data, &key_size);
+        nvs_erase_key(_handle, _name);
+      } else {
+        log_i("New EEPROM of %d bytes", size);
+      }
+      nvs_commit(_handle);
+      nvs_set_blob(_handle, _name, key_data, size);
+      free(key_data);
+      nvs_commit(_handle);
+  }
 
   if (_data) {
     delete[] _data;
   }
 
   _data = new uint8_t[size];
-  _size = size;
-  bool ret = false;
-  if (esp_partition_read (_mypart, 0, (void *) _data, _size) == ESP_OK) {
-    ret = true;
-  }
-
-  return ret;
+  nvs_get_blob(_handle, _name, _data, &_size);
+  return true;
 }
 
 void EEPROMClass::end() {
@@ -134,30 +176,22 @@ void EEPROMClass::write(int address, uint8_t value) {
 
 bool EEPROMClass::commit() {
   bool ret = false;
-  if (!_size)
+  if (!_size) {
       return false;
-  if (!_dirty)
-    return true;
-  if (!_data)
+  }
+  if (!_data) {
       return false;
-
-
-  if (esp_partition_erase_range(_mypart, 0, SPI_FLASH_SEC_SIZE) != ESP_OK)
-  {
-    log_e( "partition erase err.");
   }
-  else
-  {
-    if (esp_partition_write(_mypart, 0, (void *)_data, _size) == ESP_ERR_INVALID_SIZE)
-    {
-      log_e( "error in Write");
+  if (!_dirty) {
+      return true;
   }
-    else
-    {
+
+  if (ESP_OK != nvs_set_blob(_handle, _name, _data, _size)) {
+      log_e( "error in write");
+  } else {
       _dirty = false;
       ret = true;
   }
-  }
 
   return ret;
 }

libraries/EEPROM/src/EEPROM.h

 /*
   EEPROM.h -ported by Paolo Becchi to Esp32 from esp8266 EEPROM
            -Modified by Elochukwu Ifediora <ifedioraelochukwuc@gmail.com>
+           -Converted to nvs lbernstone@gmail.com
 
-  Uses a one sector flash partition defined in partition table
-  OR
-  Multiple sector flash partitions defined by the name column in the partition table
+  Uses a nvs byte array to emulate EEPROM
 
   Copyright (c) 2014 Ivan Grokhotkov. All rights reserved.
   This file is part of the esp8266 core for Arduino environment.
@@ -30,19 +29,9 @@
 #define EEPROM_FLASH_PARTITION_NAME "eeprom"
 #endif
 #include <Arduino.h>
-extern "C" {
-
-#include <stddef.h>
-#include <stdint.h>
-#include <string.h>
-#include <esp_partition.h>
-}
-
-//
-//   need to define AT LEAST a flash partition for EEPROM  with above name
-//
-//           eeprom , data , 0x99, start address, 0x1000
-//
+
+typedef uint32_t nvs_handle;
+
 class EEPROMClass {
   public:
     EEPROMClass(uint32_t sector);
@@ -117,11 +106,10 @@ class EEPROMClass {
     template <class T> T writeAll (int address, const T &);
 
   protected:
-    uint32_t _sector;
+    nvs_handle _handle;
     uint8_t* _data;
     size_t _size;
     bool _dirty;
-    const esp_partition_t * _mypart;
     const char* _name;
     uint32_t _user_defined_size;
 };

tools/partitions/default.csv

@@ -3,5 +3,4 @@ nvs,      data, nvs,     0x9000,  0x5000,
 otadata,  data, ota,     0xe000,  0x2000,
 app0,     app,  ota_0,   0x10000, 0x140000,
 app1,     app,  ota_1,   0x150000,0x140000,
-eeprom,   data, 0x99,    0x290000,0x1000,
-spiffs,   data, spiffs,  0x291000,0x16F000,
+spiffs,   data, spiffs,  0x290000,0x170000,

tools/partitions/default_16MB.csv

@@ -3,5 +3,4 @@ nvs,      data, nvs,     0x9000,  0x5000,
 otadata,  data, ota,     0xe000,  0x2000,
 app0,     app,  ota_0,   0x10000, 0x640000,
 app1,     app,  ota_1,   0x650000,0x640000,
-eeprom,   data, 0x99,    0xc90000,0x1000,
-spiffs,   data, spiffs,  0xc91000,0x36F000,
+spiffs,   data, spiffs,  0xc90000,0x370000,
\ No newline at end of file

tools/partitions/default_8MB.csv

@@ -3,5 +3,4 @@ nvs,      data, nvs,     0x9000,  0x5000,
 otadata,  data, ota,     0xe000,  0x2000,
 app0,     app,  ota_0,   0x10000, 0x330000,
 app1,     app,  ota_1,   0x340000,0x330000,
-eeprom,   data, 0x99,    0x670000,0x1000,
-spiffs,   data, spiffs,  0x671000,0x18F000,
+spiffs,   data, spiffs,  0x670000,0x190000,

tools/partitions/default_ffat.csv

@@ -3,5 +3,4 @@ nvs,      data, nvs,     0x9000,  0x5000,
 otadata,  data, ota,     0xe000,  0x2000,
 app0,     app,  ota_0,   0x10000, 0x140000,
 app1,     app,  ota_1,   0x150000,0x140000,
-eeprom,   data, 0x99,    0x290000,0x1000,
-ffat,     data, fat,     0x291000,0x16F000,
+ffat,     data, fat,     0x291000,0x170000,

tools/partitions/ffat.csv

@@ -3,6 +3,5 @@ nvs,      data, nvs,     0x9000,  0x5000,
 otadata,  data, ota,     0xe000,  0x2000,
 app0,     app,  ota_0,   0x10000, 0x200000,
 app1,     app,  ota_1,   0x210000,0x200000,
-eeprom,   data, 0x99,    0x410000,0x1000,
-ffat,     data, fat,     0x411000,0xBEE000,
+ffat,     data, fat,     0x410000,0xBEF000,
 # to create/use ffat, see https://github.com/marcmerlin/esp32_fatfsimage

tools/partitions/huge_app.csv

@@ -2,5 +2,4 @@
 nvs,      data, nvs,     0x9000,  0x5000,
 otadata,  data, ota,     0xe000,  0x2000,
 app0,     app,  ota_0,   0x10000, 0x300000,
-eeprom,   data, 0x99,    0x310000,0x1000,
-spiffs,   data, spiffs,  0x311000,0xEF000,
+spiffs,   data, spiffs,  0x310000,0xF0000,

tools/partitions/large_spiffs_16MB.csv

@@ -3,5 +3,4 @@ nvs,      data, nvs,     0x9000,  0x5000,
 otadata,  data, ota,     0xe000,  0x2000,
 app0,     app,  ota_0,   0x10000, 0x480000,
 app1,     app,  ota_1,   0x490000,0x480000,
-eeprom,   data, 0x99,    0x910000,0x1000,
-spiffs,   data, spiffs,  0x911000,0x6EF000,
+spiffs,   data, spiffs,  0x910000,0x6F0000,
\ No newline at end of file

tools/partitions/min_spiffs.csv

@@ -3,5 +3,4 @@ nvs,      data, nvs,     0x9000,  0x5000,
 otadata,  data, ota,     0xe000,  0x2000,
 app0,     app,  ota_0,   0x10000, 0x1E0000,
 app1,     app,  ota_1,   0x1F0000,0x1E0000,
-eeprom,   data, 0x99,    0x3D0000,0x1000,
-spiffs,   data, spiffs,  0x3D1000,0x2F000,
+spiffs,   data, spiffs,  0x3D0000,0x30000,

tools/partitions/minimal.csv

@@ -2,5 +2,4 @@
 nvs,      data, nvs,     0x9000,   0x5000,
 otadata,  data, ota,     0xe000,   0x2000,
 app0,     app,  ota_0,   0x10000,  0x140000,
-eeprom,   data, 0x99,    0x150000, 0x1000,
-spiffs,   data, spiffs,  0x151000, 0xAF000,
+spiffs,   data, spiffs,  0x150000, 0xB0000,

tools/partitions/no_ota.csv

@@ -2,5 +2,4 @@
 nvs,      data, nvs,     0x9000,  0x5000,
 otadata,  data, ota,     0xe000,  0x2000,
 app0,     app,  ota_0,   0x10000, 0x200000,
-eeprom,   data, 0x99,    0x210000,0x1000,
-spiffs,   data, spiffs,  0x211000,0x1EF000,
+spiffs,   data, spiffs,  0x210000,0x1F0000,

tools/partitions/noota_3g.csv

@@ -2,5 +2,4 @@
 nvs,      data, nvs,     0x9000,  0x5000,
 otadata,  data, ota,     0xe000,  0x2000,
 app0,     app,  ota_0,   0x10000, 0x100000,
-eeprom,   data, 0x99,    0x110000,0x1000,
-spiffs,   data, spiffs,  0x111000,0x2EF000,
+spiffs,   data, spiffs,  0x110000,0x2F0000,

tools/partitions/noota_3gffat.csv

@@ -2,6 +2,5 @@
 nvs,      data, nvs,     0x9000,  0x5000,
 otadata,  data, ota,     0xe000,  0x2000,
 app0,     app,  ota_0,   0x10000, 0x100000,
-eeprom,   data, 0x99,    0x110000,0x1000,
-ffat,     data, fat,     0x111000,0x2EF000,
+ffat,     data, fat,     0x110000,0x2F0000,
 # to create/use ffat, see https://github.com/marcmerlin/esp32_fatfsimage

tools/partitions/noota_ffat.csv

@@ -2,6 +2,5 @@
 nvs,      data, nvs,     0x9000,  0x5000,
 otadata,  data, ota,     0xe000,  0x2000,
 app0,     app,  ota_0,   0x10000, 0x200000,
-eeprom,   data, 0x99,    0x210000,0x1000,
-ffat,     data, fat,     0x211000,0x1EF000,
+ffat,     data, fat,     0x210000,0x1F0000,
 # to create/use ffat, see https://github.com/marcmerlin/esp32_fatfsimage