Optimize tagDB and reduce RAM usage (#113)

* Reduce code size by removing nullptr assignments * Optimize tagDB for loops * More tagDB optimizations * Remove static from language arrays reducing RAM by 5128b - Reduces Flash by 13060b * Add missing extern in tag_db.h * Fix deprecation warning of sntp.h * Remove static from contentmanager, reduces RAM by 184b * Use string reference in prepareDataAvail - Remove some unneeded buffers - Remove some gotos
2026-03-21 11:06:49 +01:00 · 2023-08-17 10:06:21 +02:00
parent a31e1453d0
commit fce6c16153
13 changed files with 188 additions and 206 deletions
--- a/ESP32_AP-Flasher/include/contentmanager.h
+++ b/ESP32_AP-Flasher/include/contentmanager.h
@@ -36,7 +36,7 @@ int getJsonTemplateUrl(String &filename, String URL, time_t fetched, String MAC,
 void drawJsonStream(Stream &stream, String &filename, tagRecord *&taginfo, imgParam &imageParams);
 void drawElement(const JsonObject &element, TFT_eSprite &spr);
 uint16_t getColor(const String &color);
-char *formatHttpDate(time_t t);
+char *formatHttpDate(const time_t t);
 String urlEncode(const char *msg);
 int windSpeedToBeaufort(const float windSpeed);
 String windDirectionIcon(const int degrees);
--- a/ESP32_AP-Flasher/include/language.h
+++ b/ESP32_AP-Flasher/include/language.h
@@ -2,32 +2,32 @@

 #include <Arduino.h>

-static int defaultLanguage = 0;
+extern int defaultLanguage;

-static String languageList[] = {"EN - English", "NL - Nederlands", "DE - Deutsch"};
+extern String languageList[];

 /*EN English language section*/
-static String languageEnDaysShort[] = {"SU", "MO", "TU", "WE", "TH", "FR", "SA"};
-static String languageEnDays[] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};
-static String languageEnMonth[] = {"January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"};
+extern String languageEnDaysShort[];
+extern String languageEnDays[];
+extern String languageEnMonth[];
 /*END English language section END*/

 /*NL Dutch language section*/
-static String languageNlDaysShort[] = {"ZO", "MA", "DI", "WO", "DO", "VR", "ZA"};
-static String languageNlDays[] = {"zondag", "maandag", "dinsdag", "woensdag", "donderdag", "vrijdag", "zaterdag"};
-static String languageNlMonth[] = {"januari", "februari", "maart", "april", "mei", "juni", "juli", "augustus", "september", "oktober", "november", "december"};
+extern String languageNlDaysShort[];
+extern String languageNlDays[];
+extern String languageNlMonth[];
 /*END Dutch language section END*/

 /*DE German language section*/
-static String languageDeDaysShort[] = {"SO", "MO", "DI", "MI", "DO", "FR", "SA"};
-static String languageDeDays[] = {"Sonntag", "Montag", "Dienstag", "Mittwoch", "Donnerstag", "Freitag", "Samstag"};
-static String languageDeMonth[] = {"Januar", "Februar", "März", "April", "Mai", "Juni", "Juli", "August", "September", "Oktober", "November", "Dezember"};
+extern String languageDeDaysShort[];
+extern String languageDeDays[];
+extern String languageDeMonth[];
 /*END German language section END*/

-static String* languageDaysShort[] = {languageEnDaysShort, languageNlDaysShort, languageDeDaysShort};
-static String* languageDays[] = {languageEnDays, languageNlDays, languageDeDays};
-static String* languageMonth[] = {languageEnMonth, languageNlMonth, languageDeMonth};
+extern String* languageDaysShort[];
+extern String* languageDays[];
+extern String* languageMonth[];

-void updateLanguageFromConfig();
-int getDefaultLanguage();
-int getCurrentLanguage();
+extern void updateLanguageFromConfig();
+extern int getDefaultLanguage();
+extern int getCurrentLanguage();
--- a/ESP32_AP-Flasher/include/newproto.h
+++ b/ESP32_AP-Flasher/include/newproto.h
@@ -7,7 +7,7 @@ extern void processBlockRequest(struct espBlockRequest* br);
 extern void prepareCancelPending(const uint8_t dst[8]);
 extern void prepareIdleReq(const uint8_t* dst, uint16_t nextCheckin);
 extern void prepareDataAvail(uint8_t* data, uint16_t len, uint8_t dataType, const uint8_t* dst);
-extern bool prepareDataAvail(String* filename, uint8_t dataType, const uint8_t* dst, uint16_t nextCheckin);
+extern bool prepareDataAvail(String& filename, uint8_t dataType, const uint8_t* dst, uint16_t nextCheckin);
 extern void prepareExternalDataAvail(struct pendingData* pending, IPAddress remoteIP);
 extern void processXferComplete(struct espXferComplete* xfc, bool local);
 extern void processXferTimeout(struct espXferComplete* xfc, bool local);
--- a/ESP32_AP-Flasher/include/tag_db.h
+++ b/ESP32_AP-Flasher/include/tag_db.h
@@ -86,20 +86,20 @@ extern std::vector<tagRecord*> tagDB;
 extern std::unordered_map<int, HwType> hwtype;
 extern std::unordered_map<std::string, varStruct> varDB;
 extern DynamicJsonDocument APconfig;
-String tagDBtoJson(const uint8_t mac[8] = nullptr, uint8_t startPos = 0);
-bool deleteRecord(const uint8_t mac[8]);
-void fillNode(JsonObject& tag, tagRecord*& taginfo);
-void saveDB(String filename);
-void loadDB(String filename);
-void destroyDB();
-uint32_t getTagCount();
-uint32_t getTagCount(uint32_t& timeoutcount);
-void mac2hex(const uint8_t* mac, char* hexBuffer);
-bool hex2mac(const String& hexString, uint8_t* mac);
-void clearPending(tagRecord* taginfo);
-void initAPconfig();
-void saveAPconfig();
-HwType getHwType(uint8_t id);
-bool setVarDB(const std::string& key, const String& value);
+extern String tagDBtoJson(const uint8_t mac[8] = nullptr, uint8_t startPos = 0);
+extern bool deleteRecord(const uint8_t mac[8]);
+extern void fillNode(JsonObject& tag, const tagRecord* taginfo);
+extern void saveDB(const String& filename);
+extern void loadDB(const String& filename);
+extern void destroyDB();
+extern uint32_t getTagCount();
+extern uint32_t getTagCount(uint32_t& timeoutcount);
+extern void mac2hex(const uint8_t* mac, char* hexBuffer);
+extern bool hex2mac(const String& hexString, uint8_t* mac);
+extern void clearPending(tagRecord* taginfo);
+extern void initAPconfig();
+extern void saveAPconfig();
+extern HwType getHwType(const uint8_t id);
+extern bool setVarDB(const std::string& key, const String& value);

 #pragma pack(pop)
--- a/ESP32_AP-Flasher/src/contentmanager.cpp
+++ b/ESP32_AP-Flasher/src/contentmanager.cpp
@@ -193,7 +193,7 @@ void drawNew(const uint8_t mac[8], const bool buttonPressed, tagRecord *&taginfo
                if (imageParams.hasRed) {
                    imageParams.dataType = DATATYPE_IMG_RAW_2BPP;
                }
-                if (prepareDataAvail(&filename, imageParams.dataType, mac, cfgobj["timetolive"].as<int>())) {
+                if (prepareDataAvail(filename, imageParams.dataType, mac, cfgobj["timetolive"].as<int>())) {
                    cfgobj["#fetched"] = true;
                    if (cfgobj["delete"].as<String>() == "1") {
                        contentFS->remove("/" + configFilename);
@@ -243,7 +243,7 @@ void drawNew(const uint8_t mac[8], const bool buttonPressed, tagRecord *&taginfo

            filename = cfgobj["filename"].as<String>();
            if (!util::isEmptyOrNull(filename) && !cfgobj["#fetched"].as<bool>()) {
-                if (prepareDataAvail(&filename, DATATYPE_FW_UPDATE, mac, cfgobj["timetolive"].as<int>())) {
+                if (prepareDataAvail(filename, DATATYPE_FW_UPDATE, mac, cfgobj["timetolive"].as<int>())) {
                    cfgobj["#fetched"] = true;
                } else {
                    wsErr("Error accessing " + filename);
@@ -395,7 +395,7 @@ bool updateTagImage(String &filename, const uint8_t *dst, uint16_t nextCheckin,
        sendAPSegmentedData(dst, (String)imageParams.segments, imageParams.symbols, imageParams.invert, (taginfo->isExternal == false));
    } else {
        if (imageParams.hasRed) imageParams.dataType = DATATYPE_IMG_RAW_2BPP;
-        prepareDataAvail(&filename, imageParams.dataType, dst, nextCheckin);
+        prepareDataAvail(filename, imageParams.dataType, dst, nextCheckin);
    }
    return true;
 }
@@ -792,8 +792,8 @@ bool getRssFeed(String &filename, String URL, String title, tagRecord *&taginfo,
    // https://www.nu.nl/rss/Algemeen

    const char *url = URL.c_str();
-    const char *tag = "title";
-    const int rssArticleSize = 128;
+    constexpr const char *tag = "title";
+    constexpr const int rssArticleSize = 128;

    TFT_eSprite spr = TFT_eSprite(&tft);
    U8g2_for_TFT_eSPI u8f;
@@ -856,7 +856,7 @@ bool getCalFeed(String &filename, String URL, String title, tagRecord *&taginfo,
    time(&now);
    struct tm timeinfo;
    localtime_r(&now, &timeinfo);
-    static char dateString[40];
+    char dateString[40];
    strftime(dateString, sizeof(dateString), "%d.%m.%Y", &timeinfo);

    HTTPClient http;
@@ -1143,7 +1143,7 @@ uint16_t getColor(const String &color) {
    return TFT_WHITE;
 }

-char *formatHttpDate(time_t t) {
+char *formatHttpDate(const time_t t) {
    static char buf[40];
    struct tm *timeinfo;
    timeinfo = localtime(&t);                 // Get the local time
@@ -1154,7 +1154,7 @@ char *formatHttpDate(time_t t) {
 }

 String urlEncode(const char *msg) {
-    static const char *hex = "0123456789ABCDEF";
+    constexpr const char *hex = "0123456789ABCDEF";
    String encodedMsg = "";

    while (*msg != '\0') {
@@ -1172,8 +1172,8 @@ String urlEncode(const char *msg) {
 }

 int windSpeedToBeaufort(const float windSpeed) {
-    constexpr static const float speeds[] = {0.3, 1.5, 3.3, 5.5, 8, 10.8, 13.9, 17.2, 20.8, 24.5, 28.5, 32.7};
-    constexpr static const int numSpeeds = sizeof(speeds) / sizeof(speeds[0]);
+    constexpr const float speeds[] = {0.3, 1.5, 3.3, 5.5, 8, 10.8, 13.9, 17.2, 20.8, 24.5, 28.5, 32.7};
+    constexpr const int numSpeeds = sizeof(speeds) / sizeof(speeds[0]);
    int beaufort = 0;
    for (int i = 0; i < numSpeeds; i++) {
        if (windSpeed >= speeds[i]) {
@@ -1184,7 +1184,7 @@ int windSpeedToBeaufort(const float windSpeed) {
 }

 String windDirectionIcon(const int degrees) {
-    static const String directions[] = {"\uf044", "\uf043", "\uf048", "\uf087", "\uf058", "\uf057", "\uf04d", "\uf088"};
+    const String directions[] = {"\uf044", "\uf043", "\uf048", "\uf087", "\uf058", "\uf057", "\uf04d", "\uf088"};
    int index = (degrees + 22) / 45;
    if (index >= 8) {
        index = 0;
@@ -1234,8 +1234,8 @@ void prepareNFCReq(const uint8_t *dst, const char *url) {
 }

 void prepareLUTreq(const uint8_t *dst, const String &input) {
-    const char *delimiters = ", \t";
-    const int maxValues = 76;
+    constexpr const char *delimiters = ", \t";
+    constexpr const int maxValues = 76;
    uint8_t waveform[maxValues];
    char *ptr = strtok(const_cast<char *>(input.c_str()), delimiters);
    int i = 0;
@@ -1269,7 +1269,7 @@ void getTemplate(JsonDocument &json, const uint8_t id, const uint8_t hwtype) {
    StaticJsonDocument<2048> doc;

    const String idstr = String(id);
-    const char *templateKey = "template";
+    constexpr const char *templateKey = "template";

    char filename[20];
    snprintf(filename, sizeof(filename), "/tagtypes/%02X.json", hwtype);
--- a/ESP32_AP-Flasher/src/ips_display.cpp
+++ b/ESP32_AP-Flasher/src/ips_display.cpp
@@ -17,8 +17,7 @@ int32_t tftid = -1;

 int32_t findId(uint8_t mac[8]) {
    for (uint32_t c = 0; c < tagDB.size(); c++) {
-        tagRecord* tag = nullptr;
-        tag = tagDB.at(c);
+        tagRecord* tag = tagDB.at(c);
        if (memcmp(tag->mac, mac, 8) == 0) {
            return c;
        }
@@ -65,8 +64,7 @@ void yellow_ap_display_loop(void) {

        // if ((uint32_t)WiFi.localIP() == (uint32_t)0) {}

-        tagRecord* tag = nullptr;
-        tag = tagDB.at(tftid);
+        tagRecord* tag = tagDB.at(tftid);
        if (tag->pending) {
            String filename = tag->filename;
            fs::File file = contentFS->open(filename);
@@ -83,7 +81,7 @@ void yellow_ap_display_loop(void) {
            void* spriteData = spr.getPointer();
            size_t bytesRead = file.readBytes((char*)spriteData, spr.width() * spr.height() * 2);
            file.close();
-            spr.pushSprite(0,0);
+            spr.pushSprite(0, 0);

            struct espXferComplete xfc = {0};
            memcpy(xfc.src, tag->mac, 8);
--- a/ESP32_AP-Flasher/src/language.cpp
+++ b/ESP32_AP-Flasher/src/language.cpp
@@ -5,6 +5,32 @@
 #include "settings.h"
 #include "tag_db.h"

+int defaultLanguage = 0;
+
+String languageList[] = {"EN - English", "NL - Nederlands", "DE - Deutsch"};
+
+/*EN English language section*/
+String languageEnDaysShort[] = {"SU", "MO", "TU", "WE", "TH", "FR", "SA"};
+String languageEnDays[] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};
+String languageEnMonth[] = {"January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"};
+/*END English language section END*/
+
+/*NL Dutch language section*/
+String languageNlDaysShort[] = {"ZO", "MA", "DI", "WO", "DO", "VR", "ZA"};
+String languageNlDays[] = {"zondag", "maandag", "dinsdag", "woensdag", "donderdag", "vrijdag", "zaterdag"};
+String languageNlMonth[] = {"januari", "februari", "maart", "april", "mei", "juni", "juli", "augustus", "september", "oktober", "november", "december"};
+/*END Dutch language section END*/
+
+/*DE German language section*/
+String languageDeDaysShort[] = {"SO", "MO", "DI", "MI", "DO", "FR", "SA"};
+String languageDeDays[] = {"Sonntag", "Montag", "Dienstag", "Mittwoch", "Donnerstag", "Freitag", "Samstag"};
+String languageDeMonth[] = {"Januar", "Februar", "März", "April", "Mai", "Juni", "Juli", "August", "September", "Oktober", "November", "Dezember"};
+/*END German language section END*/
+
+String* languageDaysShort[] = {languageEnDaysShort, languageNlDaysShort, languageDeDaysShort};
+String* languageDays[] = {languageEnDays, languageNlDays, languageDeDays};
+String* languageMonth[] = {languageEnMonth, languageNlMonth, languageDeMonth};
+
 int currentLanguage = defaultLanguage;

 void updateLanguageFromConfig() {
--- a/ESP32_AP-Flasher/src/newproto.cpp
+++ b/ESP32_AP-Flasher/src/newproto.cpp
@@ -13,6 +13,7 @@
 #include "system.h"
 #include "tag_db.h"
 #include "udp.h"
+#include "util.h"
 #include "web.h"

 extern uint16_t sendBlock(const void* data, const uint16_t len);
@@ -34,14 +35,15 @@ bool checkCRC(void* p, uint8_t len) {
    return ((uint8_t*)p)[0] == total;
 }

-uint8_t* getDataForFile(fs::File* file) {
-    uint8_t* ret = nullptr;
-    ret = (uint8_t*)malloc(file->size());
+uint8_t* getDataForFile(fs::File& file) {
+    const size_t fileSize = file.size();
+    uint8_t* ret = (uint8_t*)malloc(fileSize);
    if (ret) {
-        file->seek(0);
-        file->readBytes((char*)ret, file->size());
+        file.seek(0);
+        file.readBytes((char*)ret, fileSize);
    } else {
-        Serial.print("malloc failed for file...\n");
+        Serial.printf("malloc failed for file with size %d\n", fileSize);
+        util::printHeap();
    }
    return ret;
 }
@@ -51,8 +53,7 @@ void prepareCancelPending(const uint8_t dst[8]) {
    memcpy(pending.targetMac, dst, 8);
    sendCancelPending(&pending);

-    tagRecord* taginfo = nullptr;
-    taginfo = tagRecord::findByMAC(dst);
+    tagRecord* taginfo = tagRecord::findByMAC(dst);
    if (taginfo == nullptr) {
        wsErr("Tag not found, this shouldn't happen.");
        return;
@@ -71,9 +72,7 @@ void prepareIdleReq(const uint8_t* dst, uint16_t nextCheckin) {
        pending.availdatainfo.nextCheckIn = nextCheckin;
        pending.attemptsLeft = 10 + config.maxsleep;

-        char buffer[64];
-        sprintf(buffer, ">SDA %02X%02X%02X%02X%02X%02X%02X%02X NOP\n", dst[7], dst[6], dst[5], dst[4], dst[3], dst[2], dst[1], dst[0]);
-        Serial.print(buffer);
+        Serial.printf(">SDA %02X%02X%02X%02X%02X%02X%02X%02X NOP\n", dst[7], dst[6], dst[5], dst[4], dst[3], dst[2], dst[1], dst[0]);
        sendDataAvail(&pending);
    }
 }
@@ -115,11 +114,11 @@ void prepareDataAvail(uint8_t* data, uint16_t len, uint8_t dataType, const uint8
    wsSendTaginfo(dst, SYNC_TAGSTATUS);
 }

-bool prepareDataAvail(String* filename, uint8_t dataType, const uint8_t* dst, uint16_t nextCheckin) {
+bool prepareDataAvail(String& filename, uint8_t dataType, const uint8_t* dst, uint16_t nextCheckin) {
    if (nextCheckin > config.maxsleep) nextCheckin = config.maxsleep;
    if (wsClientCount() && config.stopsleep == 1) nextCheckin = 0;
 #ifdef YELLOW_IPS_AP
-    if (*filename == "direct") {
+    if (filename == "direct") {
        char dst_path[64];
        sprintf(dst_path, "/current/%02X%02X%02X%02X%02X%02X%02X%02X.raw\0", dst[7], dst[6], dst[5], dst[4], dst[3], dst[2], dst[1], dst[0]);
        contentFS->remove(dst_path);
@@ -127,26 +126,25 @@ bool prepareDataAvail(String* filename, uint8_t dataType, const uint8_t* dst, ui
    }
 #endif

-    tagRecord* taginfo = nullptr;
-    taginfo = tagRecord::findByMAC(dst);
+    tagRecord* taginfo = tagRecord::findByMAC(dst);
    if (taginfo == nullptr) {
        wsErr("Tag not found, this shouldn't happen.");
        return true;
    }

-    *filename = "/" + *filename;
+    filename = "/" + filename;
    Storage.begin();

-    if (!contentFS->exists(*filename)) {
-        wsErr("File not found. " + *filename);
+    if (!contentFS->exists(filename)) {
+        wsErr("File not found. " + filename);
        return false;
    }

-    fs::File file = contentFS->open(*filename);
+    fs::File file = contentFS->open(filename);
    uint32_t filesize = file.size();
    if (filesize == 0) {
        file.close();
-        wsErr("File has size 0. " + *filename);
+        wsErr("File has size 0. " + filename);
        return false;
    }

@@ -166,8 +164,8 @@ bool prepareDataAvail(String* filename, uint8_t dataType, const uint8_t* dst, ui
    if (memcmp(md5bytes, taginfo->md5pending, 16) == 0) {
        wsLog("new image is the same as current or already pending image. not updating tag.");
        wsSendTaginfo(dst, SYNC_TAGSTATUS);
-        if (contentFS->exists(*filename)) {
-            contentFS->remove(*filename);
+        if (contentFS->exists(filename)) {
+            contentFS->remove(filename);
        }
        return true;
    }
@@ -190,15 +188,15 @@ bool prepareDataAvail(String* filename, uint8_t dataType, const uint8_t* dst, ui
        if (contentFS->exists(dst_path)) {
            contentFS->remove(dst_path);
        }
-        contentFS->rename(*filename, dst_path);
-        *filename = String(dst_path);
+        contentFS->rename(filename, dst_path);
+        filename = String(dst_path);

        wsLog("new image: " + String(dst_path));
        time_t now;
        time(&now);
        taginfo->expectedNextCheckin = now + nextCheckin * 60 + 60;
        clearPending(taginfo);
-        taginfo->filename = *filename;
+        taginfo->filename = filename;
        taginfo->len = filesize;
        taginfo->dataType = dataType;
        taginfo->pending = true;
@@ -206,7 +204,7 @@ bool prepareDataAvail(String* filename, uint8_t dataType, const uint8_t* dst, ui
    } else {
        wsLog("firmware upload pending");
        clearPending(taginfo);
-        taginfo->filename = *filename;
+        taginfo->filename = filename;
        taginfo->len = filesize;
        taginfo->dataType = dataType;
        taginfo->pending = true;
@@ -222,22 +220,18 @@ bool prepareDataAvail(String* filename, uint8_t dataType, const uint8_t* dst, ui
    pending.attemptsLeft = attempts;
    checkMirror(taginfo, &pending);
    if (taginfo->isExternal == false) {
-        char buffer[64];
-        sprintf(buffer, ">SDA %02X%02X%02X%02X%02X%02X%02X%02X TYPE 0x%02X\n\0", dst[7], dst[6], dst[5], dst[4], dst[3], dst[2], dst[1], dst[0], pending.availdatainfo.dataType);
-        Serial.print(buffer);
+        Serial.printf(">SDA %02X%02X%02X%02X%02X%02X%02X%02X TYPE 0x%02X\n", dst[7], dst[6], dst[5], dst[4], dst[3], dst[2], dst[1], dst[0], pending.availdatainfo.dataType);
        sendDataAvail(&pending);
    } else {
        udpsync.netSendDataAvail(&pending);
    }

    wsSendTaginfo(dst, SYNC_TAGSTATUS);
-
    return true;
 }

 void prepareExternalDataAvail(struct pendingData* pending, IPAddress remoteIP) {
-    tagRecord* taginfo = nullptr;
-    taginfo = tagRecord::findByMAC(pending->targetMac);
+    tagRecord* taginfo = tagRecord::findByMAC(pending->targetMac);
    if (taginfo == nullptr) {
        return;
    }
@@ -335,8 +329,7 @@ void processBlockRequest(struct espBlockRequest* br) {
        return;
    }

-    tagRecord* taginfo = nullptr;
-    taginfo = tagRecord::findByMAC(br->src);
+    tagRecord* taginfo = tagRecord::findByMAC(br->src);
    if (taginfo == nullptr) {
        prepareCancelPending(br->src);
        Serial.printf("blockrequest: couldn't find taginfo %02X%02X%02X%02X%02X%02X%02X%02X\n", br->src[7], br->src[6], br->src[5], br->src[4], br->src[3], br->src[2], br->src[1], br->src[0]);
@@ -351,7 +344,7 @@ void processBlockRequest(struct espBlockRequest* br) {
            prepareCancelPending(br->src);
            return;
        }
-        taginfo->data = getDataForFile(&file);
+        taginfo->data = getDataForFile(file);
        file.close();
    }

@@ -400,8 +393,7 @@ void processXferComplete(struct espXferComplete* xfc, bool local) {

    time_t now;
    time(&now);
-    tagRecord* taginfo = nullptr;
-    taginfo = tagRecord::findByMAC(xfc->src);
+    tagRecord* taginfo = tagRecord::findByMAC(xfc->src);
    if (taginfo != nullptr) {
        memcpy(taginfo->md5, taginfo->md5pending, sizeof(taginfo->md5pending));
        clearPending(taginfo);
@@ -430,8 +422,7 @@ void processXferTimeout(struct espXferComplete* xfc, bool local) {

    time_t now;
    time(&now);
-    tagRecord* taginfo = nullptr;
-    taginfo = tagRecord::findByMAC(xfc->src);
+    tagRecord* taginfo = tagRecord::findByMAC(xfc->src);
    if (taginfo != nullptr) {
        taginfo->expectedNextCheckin = now + 60;
        memset(taginfo->md5pending, 0, 16 * sizeof(uint8_t));
@@ -445,8 +436,7 @@ void processDataReq(struct espAvailDataReq* eadr, bool local) {
    if (config.runStatus == RUNSTATUS_STOP) return;
    char buffer[64];

-    tagRecord* taginfo = nullptr;
-    taginfo = tagRecord::findByMAC(eadr->src);
+    tagRecord* taginfo = tagRecord::findByMAC(eadr->src);
    if (taginfo == nullptr) {
        taginfo = new tagRecord;
        memcpy(taginfo->mac, eadr->src, sizeof(taginfo->mac));
@@ -528,8 +518,7 @@ void processDataReq(struct espAvailDataReq* eadr, bool local) {

 void refreshAllPending() {
    for (int16_t c = 0; c < tagDB.size(); c++) {
-        tagRecord* taginfo = nullptr;
-        taginfo = tagDB.at(c);
+        tagRecord* taginfo = tagDB.at(c);
        if (taginfo->pending) {
            clearPending(taginfo);
            taginfo->nextupdate = 0;
@@ -541,8 +530,7 @@ void refreshAllPending() {
 };

 void updateContent(const uint8_t* dst) {
-    tagRecord* taginfo = nullptr;
-    taginfo = tagRecord::findByMAC(dst);
+    tagRecord* taginfo = tagRecord::findByMAC(dst);
    if (taginfo != nullptr) {
        clearPending(taginfo);
        taginfo->nextupdate = 0;
@@ -574,9 +562,7 @@ bool sendAPSegmentedData(const uint8_t* dst, String data, uint16_t icons, bool i
    pending.availdatainfo.dataTypeArgument = inverted;
    pending.availdatainfo.nextCheckIn = 0;
    pending.attemptsLeft = 120;
-    char buffer[64];
-    sprintf(buffer, ">AP Segmented Data %02X%02X%02X%02X%02X%02X%02X%02X\n\0", dst[7], dst[6], dst[5], dst[4], dst[3], dst[2], dst[1], dst[0]);
-    Serial.print(buffer);
+    Serial.printf(">AP Segmented Data %02X%02X%02X%02X%02X%02X%02X%02X\n\0", dst[7], dst[6], dst[5], dst[4], dst[3], dst[2], dst[1], dst[0]);
    if (local) {
        return sendDataAvail(&pending);
    } else {
@@ -594,9 +580,7 @@ bool showAPSegmentedInfo(const uint8_t* dst, bool local) {
    pending.availdatainfo.dataTypeArgument = 0;
    pending.availdatainfo.nextCheckIn = 0;
    pending.attemptsLeft = 120;
-    char buffer[64];
-    sprintf(buffer, ">SDA %02X%02X%02X%02X%02X%02X%02X%02X\n\0", dst[7], dst[6], dst[5], dst[4], dst[3], dst[2], dst[1], dst[0]);
-    Serial.print(buffer);
+    Serial.printf(">SDA %02X%02X%02X%02X%02X%02X%02X%02X\n\0", dst[7], dst[6], dst[5], dst[4], dst[3], dst[2], dst[1], dst[0]);
    if (local) {
        return sendDataAvail(&pending);
    } else {
@@ -612,9 +596,7 @@ bool sendTagCommand(const uint8_t* dst, uint8_t cmd, bool local) {
    pending.availdatainfo.dataTypeArgument = cmd;
    pending.availdatainfo.nextCheckIn = 0;
    pending.attemptsLeft = 120;
-    char buffer[64];
-    sprintf(buffer, ">Tag CMD %02X%02X%02X%02X%02X%02X%02X%02X\n\0", dst[7], dst[6], dst[5], dst[4], dst[3], dst[2], dst[1], dst[0]);
-    Serial.print(buffer);
+    Serial.printf(">Tag CMD %02X%02X%02X%02X%02X%02X%02X%02X\n\0", dst[7], dst[6], dst[5], dst[4], dst[3], dst[2], dst[1], dst[0]);
    if (local) {
        return sendDataAvail(&pending);
    } else {
@@ -624,8 +606,7 @@ bool sendTagCommand(const uint8_t* dst, uint8_t cmd, bool local) {
 }

 void updateTaginfoitem(struct TagInfo* taginfoitem) {
-    tagRecord* taginfo = nullptr;
-    taginfo = tagRecord::findByMAC(taginfoitem->mac);
+    tagRecord* taginfo = tagRecord::findByMAC(taginfoitem->mac);

    if (taginfo == nullptr) {
        taginfo = new tagRecord;
@@ -673,8 +654,7 @@ void updateTaginfoitem(struct TagInfo* taginfoitem) {

 bool checkMirror(struct tagRecord* taginfo, struct pendingData* pending) {
    for (int16_t c = 0; c < tagDB.size(); c++) {
-        tagRecord* taginfo2 = nullptr;
-        taginfo2 = tagDB.at(c);
+        tagRecord* taginfo2 = tagDB.at(c);
        if (taginfo2->contentMode == 20) {
            DynamicJsonDocument doc(500);
            deserializeJson(doc, taginfo2->modeConfigJson);
@@ -686,7 +666,7 @@ bool checkMirror(struct tagRecord* taginfo, struct pendingData* pending) {
                    if (!file) {
                        return false;
                    }
-                    taginfo->data = getDataForFile(&file);
+                    taginfo->data = getDataForFile(file);
                    file.close();
                }

--- a/ESP32_AP-Flasher/src/serialap.cpp
+++ b/ESP32_AP-Flasher/src/serialap.cpp
@@ -40,7 +40,7 @@ struct espSetChannelPower curChannel = {0, 11, 10};
 volatile uint32_t lastAPActivity = 0;
 struct APInfoS apInfo;

-extern uint8_t* getDataForFile(File* file);
+extern uint8_t* getDataForFile(File& file);

 struct rxCmd {
    uint8_t* data;
@@ -207,16 +207,16 @@ bool sendDataAvail(struct pendingData* pending) {
        for (uint8_t c = 0; c < sizeof(struct pendingData); c++) {
            AP_SERIAL_PORT.write(((uint8_t*)pending)[c]);
        }
-        if (waitCmdReply()) goto sdasend;
+        if (waitCmdReply()) {
+            txEnd();
+            return true;
+        }
        Serial.printf("SDA send failed in try %d\n", attempt);
        delay(200);
    }
    Serial.print("SDA failed to send...\n");
    txEnd();
    return false;
-sdasend:
-    txEnd();
-    return true;
 }
 bool sendCancelPending(struct pendingData* pending) {
    if (!apInfo.isOnline) return false;
@@ -228,15 +228,15 @@ bool sendCancelPending(struct pendingData* pending) {
        for (uint8_t c = 0; c < sizeof(struct pendingData); c++) {
            AP_SERIAL_PORT.write(((uint8_t*)pending)[c]);
        }
-        if (waitCmdReply()) goto cxdsent;
+        if (waitCmdReply()) {
+            txEnd();
+            return true;
+        }
        Serial.printf("CXD send failed in try %d\n", attempt);
    }
    Serial.print("CXD failed to send...\n");
    txEnd();
    return false;
-cxdsent:
-    txEnd();
-    return true;
 }
 bool sendChannelPower(struct espSetChannelPower* scp) {
    if ((apInfo.state != AP_STATE_ONLINE) && (apInfo.state != AP_STATE_COMING_ONLINE)) return false;
@@ -248,41 +248,41 @@ bool sendChannelPower(struct espSetChannelPower* scp) {
        for (uint8_t c = 0; c < sizeof(struct espSetChannelPower); c++) {
            AP_SERIAL_PORT.write(((uint8_t*)scp)[c]);
        }
-        if (waitCmdReply()) goto scpSent;
+        if (waitCmdReply()) {
+            txEnd();
+            return true;
+        }
        Serial.printf("SCP send failed in try %d\n", attempt);
    }
    Serial.print("SCP failed to send...\n");
    txEnd();
    return false;
-scpSent:
-    txEnd();
-    return true;
 }
 bool sendPing() {
    if (!txStart()) return false;
    for (uint8_t attempt = 0; attempt < 5; attempt++) {
        cmdReplyValue = CMD_REPLY_WAIT;
        AP_SERIAL_PORT.print("RDY?");
-        if (waitCmdReply()) goto pingSent;
+        if (waitCmdReply()) {
+            txEnd();
+            return true;
+        }
    }
    txEnd();
    return false;
-pingSent:
-    txEnd();
-    return true;
 }
 bool sendGetInfo() {
    if (!txStart()) return false;
    for (uint8_t attempt = 0; attempt < 5; attempt++) {
        cmdReplyValue = CMD_REPLY_WAIT;
        AP_SERIAL_PORT.print("NFO?");
-        if (waitCmdReply()) goto nfoRequested;
+        if (waitCmdReply()) {
+            txEnd();
+            return true;
+        }
    }
    txEnd();
    return false;
-nfoRequested:
-    txEnd();
-    return true;
 }

 // add RX'd request from the AP to the processor queue
--- a/ESP32_AP-Flasher/src/system.cpp
+++ b/ESP32_AP-Flasher/src/system.cpp
@@ -3,7 +3,7 @@
 #include <Arduino.h>
 #include <FS.h>
 #include <Preferences.h>
-#include <sntp.h>
+#include <esp_sntp.h>

 #include "storage.h"
 #include "tag_db.h"
--- a/ESP32_AP-Flasher/src/tag_db.cpp
+++ b/ESP32_AP-Flasher/src/tag_db.cpp
@@ -22,9 +22,7 @@ Config config;
 // SemaphoreHandle_t tagDBOwner;

 tagRecord* tagRecord::findByMAC(const uint8_t mac[8]) {
-    for (int32_t c = 0; c < tagDB.size(); c++) {
-        tagRecord* tag = nullptr;
-        tag = tagDB.at(c);
+    for (tagRecord* tag : tagDB) {
        if (memcmp(tag->mac, mac, 8) == 0) {
            return tag;
        }
@@ -33,7 +31,7 @@ tagRecord* tagRecord::findByMAC(const uint8_t mac[8]) {
 }

 bool deleteRecord(const uint8_t mac[8]) {
-    for (int32_t c = 0; c < tagDB.size(); c++) {
+    for (uint32_t c = 0; c < tagDB.size(); c++) {
        tagRecord* tag = tagDB.at(c);
        if (memcmp(tag->mac, mac, 8) == 0) {
            if (tag->data != nullptr) {
@@ -73,18 +71,10 @@ String tagDBtoJson(const uint8_t mac[8], uint8_t startPos) {
    DynamicJsonDocument doc(5000);
    JsonArray tags = doc.createNestedArray("tags");

-    for (int16_t c = startPos; c < tagDB.size(); c++) {
-        tagRecord* taginfo = nullptr;
-        taginfo = tagDB.at(c);
+    for (uint32_t c = startPos; c < tagDB.size(); ++c) {
+        const tagRecord* taginfo = tagDB.at(c);

-        bool select = false;
-        if (mac) {
-            if (memcmp(taginfo->mac, mac, 8) == 0) {
-                select = true;
-            }
-        } else {
-            select = true;
-        }
+        const bool select = !mac || memcmp(taginfo->mac, mac, 8) == 0;
        if (select) {
            JsonObject tag = tags.createNestedObject();
            fillNode(tag, taginfo);
@@ -92,15 +82,17 @@ String tagDBtoJson(const uint8_t mac[8], uint8_t startPos) {
                break;
            }
        }
+
        if (doc.capacity() - doc.memoryUsage() < doc.memoryUsage() / (c + 1) + 500) {
            doc["continu"] = c + 1;
            break;
        }
    }
+
    return doc.as<String>();
 }

-void fillNode(JsonObject& tag, tagRecord*& taginfo) {
+void fillNode(JsonObject& tag, const tagRecord* taginfo) {
    char hexmac[17];
    mac2hex(taginfo->mac, hexmac);
    tag["mac"] = String(hexmac);
@@ -130,10 +122,10 @@ void fillNode(JsonObject& tag, tagRecord*& taginfo) {
    tag["ver"] = taginfo->tagSoftwareVersion;
 }

-void saveDB(String filename) {
+void saveDB(const String& filename) {
    DynamicJsonDocument doc(2500);

-    long t = millis();
+    const long t = millis();

    Storage.begin();
    fs::File file = contentFS->open(filename, "w");
@@ -143,11 +135,9 @@ void saveDB(String filename) {
    }

    file.write('[');
-
-    for (int32_t c = 0; c < tagDB.size(); c++) {
+    for (size_t c = 0; c < tagDB.size(); c++) {
+        const tagRecord* taginfo = tagDB.at(c);
        doc.clear();
-        tagRecord* taginfo = nullptr;
-        taginfo = tagDB.at(c);

        JsonObject tag = doc.createNestedObject();
        fillNode(tag, taginfo);
@@ -160,15 +150,11 @@ void saveDB(String filename) {

    file.close();
    Serial.println("DB saved " + String(millis() - t) + "ms");
-
-    return;
 }

-void loadDB(String filename) {
-    StaticJsonDocument<1000> doc;
-
+void loadDB(const String& filename) {
    Serial.println("reading DB from file");
-    long t = millis();
+    const long t = millis();

    Storage.begin();
    fs::File readfile = contentFS->open(filename, "r");
@@ -182,6 +168,7 @@ void loadDB(String filename) {
    bool parsing = true;

    if (readfile.find("[")) {
+        StaticJsonDocument<1000> doc;
        while (parsing) {
            DeserializationError err = deserializeJson(doc, readfile);
            if (!err) {
@@ -189,8 +176,7 @@ void loadDB(String filename) {
                String dst = tag["mac"].as<String>();
                uint8_t mac[8];
                if (hex2mac(dst, mac)) {
-                    tagRecord* taginfo = nullptr;
-                    taginfo = tagRecord::findByMAC(mac);
+                    tagRecord* taginfo = tagRecord::findByMAC(mac);
                    if (taginfo == nullptr) {
                        taginfo = new tagRecord;
                        memcpy(taginfo->mac, mac, sizeof(taginfo->mac));
@@ -198,7 +184,7 @@ void loadDB(String filename) {
                    }
                    String md5 = tag["hash"].as<String>();
                    if (md5.length() >= 32) {
-                        for (int i = 0; i < 16; i++) {
+                        for (uint8_t i = 0; i < 16; i++) {
                            taginfo->md5[i] = strtoul(md5.substring(i * 2, i * 2 + 2).c_str(), NULL, 16);
                        }
                    }
@@ -236,22 +222,20 @@ void loadDB(String filename) {
    }

    readfile.close();
-    return;
+    Serial.println("loadDB took " + String(millis() - t) + "ms");
 }

 void destroyDB() {
    Serial.println("destoying DB");
    util::printHeap();
-    for (uint32_t c = 0; c < tagDB.size(); c++) {
-        tagRecord* tag = nullptr;
-        tag = tagDB.at(c);
+    for (tagRecord*& tag : tagDB) {
        if (tag->data != nullptr) {
            free(tag->data);
        }
        tag->data = nullptr;
-        delete tagDB[c];
-        tagDB.erase(tagDB.begin() + c);
+        delete tag;
    }
+    tagDB.clear();
    util::printHeap();
 }

@@ -264,19 +248,15 @@ uint32_t getTagCount(uint32_t& timeoutcount) {
    uint32_t tagcount = 0;
    time_t now;
    time(&now);
-    for (uint32_t c = 0; c < tagDB.size(); c++) {
-        tagRecord* taginfo = nullptr;
-        taginfo = tagDB.at(c);
-        if (taginfo->isExternal == false) tagcount++;
-        int32_t timeout = now - taginfo->lastseen;
+    for (const tagRecord* taginfo : tagDB) {
+        if (!taginfo->isExternal) tagcount++;
+        const int32_t timeout = now - taginfo->lastseen;
        if (taginfo->expectedNextCheckin < 3600) {
            // not initialised, timeout if not seen last 10 minutes
            if (timeout > 600) timeoutcount++;
-        } else {
-            if (now - taginfo->expectedNextCheckin > 600) {
-                //expected checkin is behind, timeout if not seen last 10 minutes
-                if (timeout > 600) timeoutcount++;
-            }
+        } else if (now - taginfo->expectedNextCheckin > 600) {
+            //expected checkin is behind, timeout if not seen last 10 minutes
+            if (timeout > 600) timeoutcount++;
        }
    }
    return tagcount;
@@ -287,10 +267,14 @@ void clearPending(tagRecord* taginfo) {
    if (taginfo->data != nullptr) {
        // check if this is the last copy of the buffer
        int datacount = 0;
-        for (uint32_t c = 0; c < tagDB.size(); c++) {
-            if (tagDB.at(c)->data == taginfo->data) datacount++;
+        for (const tagRecord* tag : tagDB) {
+            if (tag->data == taginfo->data) {
+                datacount++;
+            }
+        }
+        if (datacount == 1) {
+            free(taginfo->data);
        }
-        if (datacount == 1) free(taginfo->data);
        taginfo->data = nullptr;
    }
    taginfo->pending = false;
@@ -342,7 +326,7 @@ void saveAPconfig() {
    configFile.close();
 }

-HwType getHwType(uint8_t id) {
+HwType getHwType(const uint8_t id) {
    try {
        return hwdata.at(id);
    } catch (const std::out_of_range&) {
@@ -383,13 +367,13 @@ bool setVarDB(const std::string& key, const String& value) {
        newVar.changed = true;
        varDB[key] = newVar;
        return true;
+    }
+
+    if (it->second.value != value) {
+        it->second.value = value;
+        it->second.changed = true;
+        return true;
    } else {
-        if (it->second.value != value) {
-            it->second.value = value;
-            it->second.changed = true;
-            return true;
-        } else {
-            return false;
-        }
+        return false;
    }
 }
--- a/ESP32_AP-Flasher/src/web.cpp
+++ b/ESP32_AP-Flasher/src/web.cpp
@@ -116,8 +116,7 @@ void wsSendTaginfo(const uint8_t *mac, uint8_t syncMode) {
        xSemaphoreGive(wsMutex);
    }
    if (syncMode > SYNC_NOSYNC) {
-        tagRecord *taginfo = nullptr;
-        taginfo = tagRecord::findByMAC(mac);
+        const tagRecord *taginfo = tagRecord::findByMAC(mac);
        if (taginfo != nullptr) {
            if (taginfo->contentMode != 12 || syncMode == SYNC_DELETE) {
                UDPcomm udpsync;
@@ -237,8 +236,7 @@ void init_web() {
            String dst = request->getParam("mac")->value();
            uint8_t mac[8];
            if (hex2mac(dst, mac)) {
-                tagRecord *taginfo = nullptr;
-                taginfo = tagRecord::findByMAC(mac);
+                const tagRecord *taginfo = tagRecord::findByMAC(mac);
                if (taginfo != nullptr) {
                    if (taginfo->pending == true) {
                        request->send_P(200, "application/octet-stream", taginfo->data, taginfo->len);
@@ -255,8 +253,7 @@ void init_web() {
            String dst = request->getParam("mac", true)->value();
            uint8_t mac[8];
            if (hex2mac(dst, mac)) {
-                tagRecord *taginfo = nullptr;
-                taginfo = tagRecord::findByMAC(mac);
+                tagRecord *taginfo = tagRecord::findByMAC(mac);
                if (taginfo != nullptr) {
                    taginfo->alias = request->getParam("alias", true)->value();
                    taginfo->modeConfigJson = request->getParam("modecfgjson", true)->value();
@@ -285,8 +282,7 @@ void init_web() {
        if (request->hasParam("mac", true) && request->hasParam("cmd", true)) {
            uint8_t mac[8];
            if (hex2mac(request->getParam("mac", true)->value(), mac)) {
-                tagRecord *taginfo = nullptr;
-                taginfo = tagRecord::findByMAC(mac);
+                tagRecord *taginfo = tagRecord::findByMAC(mac);
                if (taginfo != nullptr) {
                    const char *cmdValue = request->getParam("cmd", true)->value().c_str();
                    if (strcmp(cmdValue, "del") == 0) {
@@ -533,8 +529,7 @@ void doImageUpload(AsyncWebServerRequest *request, String filename, size_t index
            String dst = request->getParam("mac", true)->value();
            uint8_t mac[8];
            if (hex2mac(dst, mac)) {
-                tagRecord *taginfo = nullptr;
-                taginfo = tagRecord::findByMAC(mac);
+                tagRecord *taginfo = tagRecord::findByMAC(mac);
                if (taginfo != nullptr) {
                    bool dither = true;
                    if (request->hasParam("dither", true)) {
@@ -575,8 +570,7 @@ void doJsonUpload(AsyncWebServerRequest *request) {
            }
            file.print(request->getParam("json", true)->value());
            file.close();
-            tagRecord *taginfo = nullptr;
-            taginfo = tagRecord::findByMAC(mac);
+            tagRecord *taginfo = tagRecord::findByMAC(mac);
            if (taginfo != nullptr) {
                uint32_t ttl = 0;
                if (request->hasParam("ttl", true)) {
--- a/ESP32_AP-Flasher/src/wifimanager.cpp
+++ b/ESP32_AP-Flasher/src/wifimanager.cpp
@@ -28,7 +28,7 @@ WifiManager::WifiManager() {
 }

 void WifiManager::poll() {
-    if (wifiStatus == AP && millis() > _nextReconnectCheck && _ssid!="") {
+    if (wifiStatus == AP && millis() > _nextReconnectCheck && _ssid != "") {
        if (apClients == 0) {
            Serial.println("Attempting to reconnect to WiFi.");
            _APstarted = false;
@@ -239,7 +239,7 @@ void WifiManager::WiFiEvent(WiFiEvent_t event) {
 #endif

 std::vector<std::string> getLocalUrl() {
-    return { String("http://" + WiFi.localIP().toString()).c_str() };
+    return {String("http://" + WiFi.localIP().toString()).c_str()};
 }

 void onErrorCallback(improv::Error err) {