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Reduce memory fragementation cause by String. #1536

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Merged
merged 2 commits into from
Jul 21, 2021
Merged

Reduce memory fragementation cause by String. #1536

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14e0e42
Reduce memory fragementation cause by String.
crankyoldgit Jul 18, 2021
a6b4e1b
Turn string reservations
crankyoldgit Jul 21, 2021
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62 changes: 49 additions & 13 deletions src/IRutils.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -116,6 +116,7 @@ decode_type_t strToDecodeType(const char * const str) {
/// @return A String containing the protocol name. kUnknownStr if no match.
String typeToString(const decode_type_t protocol, const bool isRepeat) {
String result = "";
result.reserve(30); // Size of longest protocol name + " (Repeat)"
const char *ptr = kAllProtocolNamesStr;
if (protocol > kLastDecodeType || protocol == decode_type_t::UNKNOWN) {
result = kUnknownStr;
Expand Down Expand Up @@ -209,12 +210,25 @@ uint16_t getCorrectedRawLength(const decode_results * const results) {
/// @return A String containing the code-ified result.
String resultToSourceCode(const decode_results * const results) {
String output = "";
const uint16_t length = getCorrectedRawLength(results);
const bool hasState = hasACState(results->decode_type);
// Reserve some space for the string to reduce heap fragmentation.
output.reserve(1536); // 1.5KB should cover most cases.
// "uint16_t rawData[9999] = {}; // LONGEST_PROTOCOL\n" = ~55 chars.
// "NNNN, " = ~7 chars on average per raw entry
// Protocols with a `state`:
// "uint8_t state[NN] = {};\n" = ~25 chars
// "0xNN, " = 6 chars per byte.
// Protocols without a `state`:
// " DEADBEEFDEADBEEF\n"
// "uint32_t address = 0xDEADBEEF;\n"
// "uint32_t command = 0xDEADBEEF;\n"
// "uint64_t data = 0xDEADBEEFDEADBEEF;" = ~116 chars max.
output.reserve(55 + (length * 7) + hasState ? 25 + (results->bits / 8) * 6
: 116);
// Start declaration
output += F("uint16_t "); // variable type
output += F("rawData["); // array name
output += uint64ToString(getCorrectedRawLength(results), 10);
output += uint64ToString(length, 10);
// array size
output += F("] = {"); // Start declaration

Expand Down Expand Up @@ -242,13 +256,13 @@ String resultToSourceCode(const decode_results * const results) {
output += F(" // ");
output += typeToString(results->decode_type, results->repeat);
// Only display the value if the decode type doesn't have an A/C state.
if (!hasACState(results->decode_type))
if (!hasState)
output += ' ' + uint64ToString(results->value, 16);
output += F("\n");

// Now dump "known" codes
if (results->decode_type != UNKNOWN) {
if (hasACState(results->decode_type)) {
if (hasState) {
#if DECODE_AC
uint16_t nbytes = results->bits / 8;
output += F("uint8_t state[");
Expand Down Expand Up @@ -292,7 +306,9 @@ String resultToTimingInfo(const decode_results * const results) {
String output = "";
String value = "";
// Reserve some space for the string to reduce heap fragmentation.
output.reserve(2048); // 2KB should cover most cases.
// "Raw Timing[NNNN]:\n\n" = 19 chars
// " +123456, " / "-123456, " = ~12 chars on avg per raw entry.
output.reserve(19 + 12 * results->rawlen); // Should be less than this.
value.reserve(6); // Max value should be 2^17 = 131072
output += F("Raw Timing[");
output += uint64ToString(results->rawlen - 1, 10);
Expand Down Expand Up @@ -341,7 +357,9 @@ String resultToHexidecimal(const decode_results * const result) {
String resultToHumanReadableBasic(const decode_results * const results) {
String output = "";
// Reserve some space for the string to reduce heap fragmentation.
output.reserve(2 * kStateSizeMax + 50); // Should cover most cases.
// "Protocol : LONGEST_PROTOCOL_NAME (Repeat)\n"
// "Code : 0x (NNNN Bits)\n" = 70 chars
output.reserve(2 * kStateSizeMax + 70); // Should cover most cases.
// Show Encoding standard
output += kProtocolStr;
output += F(" : ");
Expand Down Expand Up @@ -479,6 +497,8 @@ namespace irutils {
String addLabeledString(const String value, const String label,
const bool precomma) {
String result = "";
// ", " + ": " = 4 chars
result.reserve(4 + value.length() + label.length());
if (precomma) result += kCommaSpaceStr;
result += label;
result += kColonSpaceStr;
Expand Down Expand Up @@ -607,7 +627,10 @@ namespace irutils {
/// @return The resulting String.
String addModelToString(const decode_type_t protocol, const int16_t model,
const bool precomma) {
String result = addIntToString(model, kModelStr, precomma);
String result = "";
// ", Model: NNN (BlahBlahEtc)" = ~40 chars for longest model name.
result.reserve(40);
result += addIntToString(model, kModelStr, precomma);
result += kSpaceLBraceStr;
result += modelToStr(protocol, model);
return result + ')';
Expand Down Expand Up @@ -636,7 +659,9 @@ namespace irutils {
/// @return The resulting String.
String addTempFloatToString(const float degrees, const bool celsius,
const bool precomma) {
String result = addIntToString(degrees, kTempStr, precomma);
String result = "";
result.reserve(14); // Assuming ", Temp: XXX.5F" is the largest.
result += addIntToString(degrees, kTempStr, precomma);
// Is it a half degree?
if (((uint16_t)(2 * degrees)) & 1) result += F(".5");
result += celsius ? 'C' : 'F';
Expand All @@ -655,7 +680,9 @@ namespace irutils {
String addModeToString(const uint8_t mode, const uint8_t automatic,
const uint8_t cool, const uint8_t heat,
const uint8_t dry, const uint8_t fan) {
String result = addIntToString(mode, kModeStr);
String result = "";
result.reserve(22); // ", Mode: NNN (UNKNOWN)"
result += addIntToString(mode, kModeStr);
result += kSpaceLBraceStr;
if (mode == automatic) result += kAutoStr;
else if (mode == cool) result += kCoolStr;
Expand All @@ -677,7 +704,9 @@ namespace irutils {
/// @return The resulting String.
String addDayToString(const uint8_t day_of_week, const int8_t offset,
const bool precomma) {
String result = addIntToString(day_of_week, kDayStr, precomma);
String result = "";
result.reserve(19); // ", Day: N (UNKNOWN)"
result += addIntToString(day_of_week, kDayStr, precomma);
result += kSpaceLBraceStr;
if ((uint8_t)(day_of_week + offset) < 7)
#if UNIT_TEST
Expand Down Expand Up @@ -706,7 +735,9 @@ namespace irutils {
const uint8_t low, const uint8_t automatic,
const uint8_t quiet, const uint8_t medium,
const uint8_t maximum) {
String result = addIntToString(speed, kFanStr);
String result = "";
result.reserve(21); // ", Fan: NNN (UNKNOWN)"
result += addIntToString(speed, kFanStr);
result += kSpaceLBraceStr;
if (speed == high) result += kHighStr;
else if (speed == low) result += kLowStr;
Expand Down Expand Up @@ -741,7 +772,9 @@ namespace irutils {
const uint8_t off,
const uint8_t leftright, const uint8_t rightleft,
const uint8_t threed, const uint8_t wide) {
String result = addIntToString(position, kSwingHStr);
String result = "";
result.reserve(30); // ", Swing(H): NNN (Left Right)"
result += addIntToString(position, kSwingHStr);
result += kSpaceLBraceStr;
if (position == automatic) {
result += kAutoStr;
Expand Down Expand Up @@ -799,7 +832,9 @@ namespace irutils {
const uint8_t low, const uint8_t lowest,
const uint8_t off, const uint8_t swing,
const uint8_t breeze, const uint8_t circulate) {
String result = addIntToString(position, kSwingVStr);
String result = "";
result.reserve(31); // ", Swing(V): NNN (Upper Middle)"
result += addIntToString(position, kSwingVStr);
result += kSpaceLBraceStr;
if (position == automatic) {
result += kAutoStr;
Expand Down Expand Up @@ -881,6 +916,7 @@ namespace irutils {
uint8_t seconds = totalseconds % 60;

String result = "";
result.reserve(42); // "99 Days, 23 Hours, 59 Minutes, 59 Seconds"
if (days)
result += uint64ToString(days) + ' ' + String((days > 1) ? kDaysStr
: kDayStr);
Expand Down