src: Remove TimeOffset:forOffsetCode(); use minutes instead of offset…

…Code; WorldClock flash actually goes down 20 bytes (#18)

src/ace_time/BasicZoneProcessor.h

@@ -24,7 +24,7 @@ class BasicZoneProcessorTest_init;
 class BasicZoneProcessorTest_setZoneInfo;
 class BasicZoneProcessorTest_createAbbreviation;
 class BasicZoneProcessorTest_calcStartDayOfMonth;
-class BasicZoneProcessorTest_calcRuleOffsetCode;
+class BasicZoneProcessorTest_calcRuleOffsetMinutes;
 
 namespace ace_time {
 
@@ -41,8 +41,8 @@ namespace basic {
  *
  * The 'era' and 'rule' variables' intermediate values calculated during the
  * init() phase. They are used to calculate the 'yearTiny', 'startEpochSeconds',
- * 'offsetCode', 'deltaCode', and 'abbrev' parameters which are used during
- * findMatch() lookup. This separation helps in moving the ZoneInfo and
+ * 'offsetMinutes', 'deltaMinutes', and 'abbrev' parameters which are used
+ * during findMatch() lookup. This separation helps in moving the ZoneInfo and
  * ZonePolicy data structures into PROGMEM.
  *
  * Ordering of fields optimized along 4-byte boundaries to help 32-bit
@@ -80,18 +80,18 @@ struct Transition {
  /** The calculated transition time of the given rule. */
  acetime_t startEpochSeconds;
 
- /** Year which applies to the ZoneEra or ZoneRule. */
- int8_t yearTiny;
-
  /**
- * The total effective UTC offsetCode at the start of transition, *including*
- * DST offset. (Maybe rename this effectiveOffsetCode?) The DST offset is
- * stored at deltaCode.
+ * The total effective UTC offset minutes at the start of transition,
+ * *including* DST offset. (Maybe rename this effectiveOffsetMinutes?) The
+ * DST offset is stored at deltaMinutes.
  */
- int8_t offsetCode;
+ int16_t offsetMinutes;
 
- /** The delta offsetCode from "standard time" at the start of transition */
- int8_t deltaCode;
+ /** The deltaMinutes from "standard time" at the start of transition */
+ int16_t deltaMinutes;
+
+ /** Year which applies to the ZoneEra or ZoneRule. */
+ int8_t yearTiny;
 
  /**
  * The calculated effective time zone abbreviation, e.g. "PST" or "PDT".
@@ -110,7 +110,7 @@ struct Transition {
  } else {
  logging::printf("startEpochSeconds: %ld\n", startEpochSeconds);
  }
- logging::printf("offsetCode: %d\n", offsetCode);
+ logging::printf("offsetMinutes: %d\n", offsetMinutes);
  logging::printf("abbrev: %s\n", abbrev);
  if (rule.isNotNull()) {
  logging::printf("Rule.fromYear: %d\n", rule.fromYearTiny());
@@ -200,16 +200,16 @@ class BasicZoneProcessor: public ZoneProcessor {
 
  TimeOffset getUtcOffset(acetime_t epochSeconds) const override {
  const basic::Transition* transition = getTransition(epochSeconds);
- int8_t code = (transition)
- ? transition->offsetCode : TimeOffset::kErrorCode;
- return TimeOffset::forOffsetCode(code);
+ int16_t minutes = (transition)
+ ? transition->offsetMinutes : TimeOffset::kErrorMinutes;
+ return TimeOffset::forMinutes(minutes);
  }
 
  TimeOffset getDeltaOffset(acetime_t epochSeconds) const override {
  const basic::Transition* transition = getTransition(epochSeconds);
- int8_t code = (transition)
- ? transition->deltaCode : TimeOffset::kErrorCode;
- return TimeOffset::forOffsetCode(code);
+ int16_t minutes = (transition)
+ ? transition->deltaMinutes : TimeOffset::kErrorMinutes;
+ return TimeOffset::forMinutes(minutes);
  }
 
  const char* getAbbrev(acetime_t epochSeconds) const override {
@@ -372,7 +372,7 @@ class BasicZoneProcessor: public ZoneProcessor {
  friend class ::BasicZoneProcessorTest_setZoneInfo;
  friend class ::BasicZoneProcessorTest_createAbbreviation;
  friend class ::BasicZoneProcessorTest_calcStartDayOfMonth;
- friend class ::BasicZoneProcessorTest_calcRuleOffsetCode;
+ friend class ::BasicZoneProcessorTest_calcRuleOffsetMinutes;
 
  template<uint8_t SIZE, uint8_t TYPE, typename ZS, typename ZI, typename ZIB>
  friend class ZoneProcessorCacheImpl; // setZoneInfo()
@@ -515,30 +515,30 @@ class BasicZoneProcessor: public ZoneProcessor {
  }
 
  /**
- * Create a Transition with the 'deltaCode' and 'offsetCode' filled in so
- * that subsequent processing does not need to retrieve those again
+ * Create a Transition with the 'deltaMinutes' and 'offsetMInutes' filled
+ * in so that subsequent processing does not need to retrieve those again
  * (potentially from PROGMEM).
  */
  static basic::Transition createTransition(basic::ZoneEraBroker era,
  basic::ZoneRuleBroker rule, int8_t yearTiny) {
- int8_t deltaCode;
+ int16_t deltaMinutes;
  char letter;
  if (rule.isNull()) {
- deltaCode = era.deltaCode();
+ deltaMinutes = era.deltaMinutes();
  letter = '\0';
  } else {
- deltaCode = rule.deltaCode();
+ deltaMinutes = rule.deltaMinutes();
  letter = rule.letter();
  }
- int8_t offsetCode = era.offsetCode() + deltaCode;
+ int16_t offsetMinutes = era.offsetMinutes() + deltaMinutes;
 
  return {
  era,
  rule,
  0 /*epochSeconds*/,
+ offsetMinutes,
+ deltaMinutes,
  yearTiny,
- offsetCode,
- deltaCode,
  {letter} /*abbrev*/
  };
  }
@@ -688,7 +688,7 @@ class BasicZoneProcessor: public ZoneProcessor {
 
  /**
  * Calculate the startEpochSeconds of each Transition. (previous, this also
- * calculated the offsetCode and deltaCode as well, but it turned out
+ * calculated the offsetMinutes and deltaMinutes as well, but it turned out
  * that they could be calculated early in createTransition()). The start
  * time of a given transition is defined as the "wall clock", which means
  * that it is defined in terms of the *previous* Transition.
@@ -707,17 +707,17 @@ class BasicZoneProcessor: public ZoneProcessor {
  // ZoneEra applies for the entire year (since BasicZoneProcessor
  // supports only whole year in the UNTIL field). The whole year UNTIL
  // field has an implied 'w' suffix on 00:00, we don't need to call
- // calcRuleOffsetCode() with a 'w', we can just use the previous
+ // calcRuleOffsetMinutes() with a 'w', we can just use the previous
  // transition's offset to calculate the startDateTime of this
  // transition.
  //
  // Also, when transition.rule == nullptr, the mNumTransitions should
  // be 1, since only a single transition is added by
  // addTransitionsForYear().
- const int8_t prevOffsetCode = prevTransition->offsetCode;
+ const int16_t prevOffsetMinutes = prevTransition->offsetMinutes;
  OffsetDateTime startDateTime = OffsetDateTime::forComponents(
  year, 1, 1, 0, 0, 0,
- TimeOffset::forOffsetCode(prevOffsetCode));
+ TimeOffset::forMinutes(prevOffsetMinutes));
  transition.startEpochSeconds = startDateTime.toEpochSeconds();
  } else {
  // In this case, the transition points to a named ZonePolicy, which
@@ -732,9 +732,9 @@ class BasicZoneProcessor: public ZoneProcessor {
 
  // Determine the offset of the 'atTimeSuffix'. The 'w' suffix
  // requires the offset of the previous transition.
- const int8_t prevOffsetCode = calcRuleOffsetCode(
- prevTransition->offsetCode,
- transition.era.offsetCode(),
+ const int16_t prevOffsetMinutes = calcRuleOffsetMinutes(
+ prevTransition->offsetMinutes,
+ transition.era.offsetMinutes(),
  transition.rule.atTimeSuffix());
 
  // startDateTime
@@ -744,7 +744,7 @@ class BasicZoneProcessor: public ZoneProcessor {
  OffsetDateTime startDateTime = OffsetDateTime::forComponents(
  year, monthDay.month, monthDay.day,
  atHour, atMinute, 0 /*second*/,
- TimeOffset::forOffsetCode(prevOffsetCode));
+ TimeOffset::forMinutes(prevOffsetMinutes));
  transition.startEpochSeconds = startDateTime.toEpochSeconds();
  }
 
@@ -758,12 +758,12 @@ class BasicZoneProcessor: public ZoneProcessor {
  * (which does not contain the extra DST offset). If 'u', 'g', 'z', then
  * use 0 offset.
  */
- static int8_t calcRuleOffsetCode(int8_t prevEffectiveOffsetCode,
- int8_t currentBaseOffsetCode, uint8_t atSuffix) {
+ static int16_t calcRuleOffsetMinutes(int16_t prevEffectiveOffsetMinutes,
+ int16_t currentBaseOffsetMinutes, uint8_t atSuffix) {
  if (atSuffix == basic::ZoneContext::TIME_SUFFIX_W) {
- return prevEffectiveOffsetCode;
+ return prevEffectiveOffsetMinutes;
  } else if (atSuffix == basic::ZoneContext::TIME_SUFFIX_S) {
- return currentBaseOffsetCode;
+ return currentBaseOffsetMinutes;
  } else { // 'u', 'g' or 'z'
  return 0;
  }
@@ -783,13 +783,13 @@ class BasicZoneProcessor: public ZoneProcessor {
  transition->abbrev,
  basic::Transition::kAbbrevSize,
  transition->era.format(),
- transition->deltaCode,
+ transition->deltaMinutes,
  transition->abbrev[0]);
  }
 
  /**
  * Create the time zone abbreviation in dest from the format string
- * (e.g. "P%T", "E%T"), the time zone deltaCode (!= 0 means DST), and the
+ * (e.g. "P%T", "E%T"), the time zone deltaMinutes (!= 0 means DST), and the
  * replacement letter (e.g. 'S', 'D', '-', or '\0' to indicate no RULE).
  *
  * 1) If the FORMAT contains a '%', then:
@@ -807,11 +807,12 @@ class BasicZoneProcessor: public ZoneProcessor {
  * in the TZ database files.)
  *
  * 2) If the FORMAT contains a '/', then, ignore the 'letter' and just
- * use deltaCode in the following:
+ * use deltaMinutes in the following:
  *
- * 2a) If deltaCode is 0, pick the first component, i.e. before the '/'.
+ * 2a) If deltaMinutes is 0, pick the first component, i.e. before the '/'.
  *
- * 2b) Else deltaCode != 0, pick the second component, i.e. after the '/'.
+ * 2b) Else deltaMinutes != 0, pick the second component, i.e. after the
+ * '/'.
  *
  * The above algorithm supports the following edge cases from the TZ
  * Database:
@@ -827,14 +828,15 @@ class BasicZoneProcessor: public ZoneProcessor {
  * @param dest destination string buffer
  * @param destSize size of buffer
  * @param format encoded abbreviation, '%' is a character substitution
- * @param deltaCode the offsetCode (0 for standard, != 0 for DST)
+ * @param deltaMinutes the additional delta minutes std offset
+ * (0 for standard, != 0 for DST)
  * @param letter during standard or DST time. If RULES is a named rule,
  * this is the value of the LETTER field ('S', 'D', '-' for empty
  * string), But if RULES is '-' or 'hh:mm' indicating a fixed offset,
  * then 'letter' will be set to '\0'.
  */
  static void createAbbreviation(char* dest, uint8_t destSize,
- const char* format, uint8_t deltaCode, char letter) {
+ const char* format, int16_t deltaMinutes, char letter) {
  // Check if FORMAT contains a '%'.
  if (strchr(format, '%') != nullptr) {
  // Check if RULES column empty, therefore no 'letter'
@@ -848,7 +850,7 @@ class BasicZoneProcessor: public ZoneProcessor {
  // Check if FORMAT contains a '/'.
  const char* slashPos = strchr(format, '/');
  if (slashPos != nullptr) {
- if (deltaCode == 0) {
+ if (deltaMinutes == 0) {
  uint8_t headLength = (slashPos - format);
  if (headLength >= destSize) headLength = destSize - 1;
  memcpy(dest, format, headLength);
@@ -860,7 +862,7 @@ class BasicZoneProcessor: public ZoneProcessor {
  dest[tailLength] = '\0';
  }
  } else {
- // Just copy the FORMAT disregarding the deltaCode and letter.
+ // Just copy the FORMAT disregarding the deltaMinutes and letter.
  strncpy(dest, format, destSize - 1);
  dest[destSize - 1] = '\0';
  }