WLED/wled00/util.cpp

#include "wled.h"
#include "fcn_declare.h"
#include "const.h"


//helper to get int value at a position in string
int getNumVal(const String* req, uint16_t pos)
{
  return req->substring(pos+3).toInt();
}


//helper to get int value with in/decrementing support via ~ syntax
void parseNumber(const char* str, byte* val, byte minv, byte maxv)
{
  if (str == nullptr || str[0] == '\0') return;
  if (str[0] == 'r') {*val = random8(minv,maxv); return;}
  if (str[0] == '~') {
    int out = atoi(str +1);
    if (out == 0)
    {
      if (str[1] == '0') return;
      if (str[1] == '-')
      {
        *val = (int)(*val -1) < (int)minv ? maxv : min((int)maxv,(*val -1)); //-1, wrap around
      } else {
        *val = (int)(*val +1) > (int)maxv ? minv : max((int)minv,(*val +1)); //+1, wrap around
      }
    } else {
      out += *val;
      if (out > maxv) out = maxv;
      if (out < minv) out = minv;
      *val = out;
    }
  } else
  {
    byte p1 = atoi(str);
    const char* str2 = strchr(str,'~'); //min/max range (for preset cycle, e.g. "1~5~")
    if (str2) {
      byte p2 = atoi(str2+1);
      presetCycMin = p1; presetCycMax = p2;
      while (isdigit((str2+1)[0])) str2++;
      parseNumber(str2+1, val, p1, p2);
    } else {
      *val = p1;
    }
  }
}


bool getVal(JsonVariant elem, byte* val, byte vmin, byte vmax) {
  if (elem.is<int>()) {
		if (elem < 0) return false; //ignore e.g. {"ps":-1}
    *val = elem;
    return true;
  } else if (elem.is<const char*>()) {
    const char* str = elem;
    size_t len = strnlen(str, 12);
    if (len == 0 || len > 10) return false;
    parseNumber(str, val, vmin, vmax);
    return true;
  }
  return false; //key does not exist
}


bool updateVal(const String* req, const char* key, byte* val, byte minv, byte maxv)
{
  int pos = req->indexOf(key);
  if (pos < 1) return false;
  if (req->length() < (unsigned int)(pos + 4)) return false;
  parseNumber(req->c_str() + pos +3, val, minv, maxv);
  return true;
}


//append a numeric setting to string buffer
void sappend(char stype, const char* key, int val)
{
  char ds[] = "d.Sf.";

  switch(stype)
  {
    case 'c': //checkbox
      oappend(ds);
      oappend(key);
      oappend(".checked=");
      oappendi(val);
      oappend(";");
      break;
    case 'v': //numeric
      oappend(ds);
      oappend(key);
      oappend(".value=");
      oappendi(val);
      oappend(";");
      break;
    case 'i': //selectedIndex
      oappend(ds);
      oappend(key);
      oappend(SET_F(".selectedIndex="));
      oappendi(val);
      oappend(";");
      break;
  }
}


//append a string setting to buffer
void sappends(char stype, const char* key, char* val)
{
  switch(stype)
  {
    case 's': {//string (we can interpret val as char*)
      String buf = val;
      //convert "%" to "%%" to make EspAsyncWebServer happy
      //buf.replace("%","%%");
      oappend("d.Sf.");
      oappend(key);
      oappend(".value=\"");
      oappend(buf.c_str());
      oappend("\";");
      break;}
    case 'm': //message
      oappend(SET_F("d.getElementsByClassName"));
      oappend(key);
      oappend(SET_F(".innerHTML=\""));
      oappend(val);
      oappend("\";");
      break;
  }
}


bool oappendi(int i)
{
  char s[11];
  sprintf(s, "%d", i);
  return oappend(s);
}


bool oappend(const char* txt)
{
  uint16_t len = strlen(txt);
  if (olen + len >= SETTINGS_STACK_BUF_SIZE)
    return false;        // buffer full
  strcpy(obuf + olen, txt);
  olen += len;
  return true;
}


void prepareHostname(char* hostname)
{
  const char *pC = serverDescription;
  uint8_t pos = 5;

  while (*pC && pos < 24) { // while !null and not over length
    if (isalnum(*pC)) {     // if the current char is alpha-numeric append it to the hostname
      hostname[pos] = *pC;
      pos++;
    } else if (*pC == ' ' || *pC == '_' || *pC == '-' || *pC == '+' || *pC == '!' || *pC == '?' || *pC == '*') {
      hostname[pos] = '-';
      pos++;
    }
      // else do nothing - no leading hyphens and do not include hyphens for all other characters.
      pC++;
    }
    // if the hostname is left blank, use the mac address/default mdns name
    if (pos < 6) {
      sprintf(hostname + 5, "%*s", 6, escapedMac.c_str() + 6);
    } else { //last character must not be hyphen
      while (pos > 0 && hostname[pos -1] == '-') {
        hostname[pos -1] = 0;
        pos--;
      }
    }
}


bool isAsterisksOnly(const char* str, byte maxLen)
{
  for (byte i = 0; i < maxLen; i++) {
    if (str[i] == 0) break;
    if (str[i] != '*') return false;
  }
  //at this point the password contains asterisks only
  return (str[0] != 0); //false on empty string
}


//threading/network callback details: https://github.com/Aircoookie/WLED/pull/2336#discussion_r762276994
bool requestJSONBufferLock(uint8_t module)
{
  unsigned long now = millis();

  while (jsonBufferLock && millis()-now < 1000) delay(1); // wait for a second for buffer lock

  if (millis()-now >= 1000) {
    DEBUG_PRINT(F("ERROR: Locking JSON buffer failed! ("));
    DEBUG_PRINT(jsonBufferLock);
    DEBUG_PRINTLN(")");
    return false; // waiting time-outed
  }

  jsonBufferLock = module ? module : 255;
  fileDoc = &doc;  // used for applying presets (presets.cpp)
  doc.clear();
  return true;
}


void releaseJSONBufferLock()
{
  DEBUG_PRINT(F("JSON buffer released. ("));
  DEBUG_PRINT(jsonBufferLock);
  DEBUG_PRINTLN(")");
  fileDoc = nullptr;
  jsonBufferLock = 0;
}


// extracts effect mode (or palette) name from names serialized string
// caller must provide large enough buffer for name (incluing SR extensions)!
uint8_t extractModeName(uint8_t mode, const char *src, char *dest, uint8_t maxLen)
{
  uint8_t qComma = 0;
  bool insideQuotes = false;
  uint8_t printedChars = 0;
  char singleJsonSymbol;
  size_t len = strlen_P(src);

  // Find the mode name in JSON
  for (size_t i = 0; i < len; i++) {
    singleJsonSymbol = pgm_read_byte_near(src + i);
    if (singleJsonSymbol == '\0') break;
    if (singleJsonSymbol == '@' && insideQuotes && qComma == mode) break; //stop when SR extension encountered
    switch (singleJsonSymbol) {
      case '"':
        insideQuotes = !insideQuotes;
        break;
      case '[':
      case ']':
        break;
      case ',':
        if (!insideQuotes) qComma++;
      default:
        if (!insideQuotes || (qComma != mode)) break;
        dest[printedChars++] = singleJsonSymbol;
    }
    if ((qComma > mode) || (printedChars >= maxLen)) break;
  }
  dest[printedChars] = '\0';
  //char *pos = strchr(dest,'@');
  //if (pos) *pos = '\0';
  return strlen(dest);
}