[RFC] Multi-language firmware (second try) (#941)

* Impl. sectioned font table in firmware

* make_translation.py: Extract build_symbol_conversion_table function

* Put translation indices and strings in a struct

* Move translation objcopy step to Python

* Impl. multi-language firmware demo

* Impl. strings-compressed multi-lang firmware demo

* Add font compression to multi-lang demo

* Refactor Makefile a bit

* Fix rules for make < 4.3

* Add more multi-lang groups

* Add Pinecil multi-lang CI build

* Add lzfx compression license text

* Remote multi-language demo group

* Fix build after merge

* Import code from BriefLZ

* Change brieflz for our use case

* Change compression to use brieflz

* Remove lzfx code

* Update license file for brieflz

* Exclude brieflz files from format check

* Add BriefLZ test

source/Core/Inc/Settings.h

@@ -10,7 +10,7 @@
 #ifndef SETTINGS_H_
 #define SETTINGS_H_
 #include <stdint.h>
-#define SETTINGSVERSION (0x29)
+#define SETTINGSVERSION (0x2A)
 /*Change this if you change the struct below to prevent people getting \
           out of sync*/
 
@@ -59,6 +59,7 @@ typedef struct {
   uint8_t  hallEffectSensitivity;          // Operating mode of the hall effect sensor
   uint8_t  accelMissingWarningCounter;     // Counter of how many times we have warned we cannot detect the accelerometer
   uint8_t  pdMissingWarningCounter;        // Counter of how many times we have warned we cannot detect the pd interface
+  char     uiLanguage[8];                  // Selected UI Language code, null-terminated *only if* the length is less than 8 chars
 
   uint32_t padding; // This is here for in case we are not an even divisor so
                     // that nothing gets cut off

source/Core/Inc/Translation.h

@@ -57,6 +57,7 @@ enum class SettingsItemIndex : uint8_t {
   AnimSpeed,
   PowerPulseWait,
   PowerPulseDuration,
+  LanguageSwitch,
   NUM_ITEMS,
 };
 
@@ -110,11 +111,28 @@ struct TranslationIndexTable {
   uint16_t SettingsMenuEntriesDescriptions[5]; // unused
 };
 
-extern const TranslationIndexTable *const Tr;
-extern const char *const                  TranslationStrings;
+extern const TranslationIndexTable *Tr;
+extern const char *                 TranslationStrings;
 
-extern const uint8_t *const Font_12x16;
-extern const uint8_t *const Font_6x8;
+struct TranslationData {
+  TranslationIndexTable indices;
+  // Translation strings follows the translation index table.
+  // C++ does not support flexible array member as in C, so we use a 1-element
+  // array as a placeholder.
+  char strings[1];
+};
+
+struct FontSection {
+  /// Start index of font section, inclusive
+  uint16_t symbol_start;
+  /// End index of font section, exclusive
+  uint16_t       symbol_end;
+  const uint8_t *font12_start_ptr;
+  const uint8_t *font06_start_ptr;
+};
+
+extern const FontSection *const FontSections;
+extern const uint8_t            FontSectionsCount;
 
 constexpr uint8_t settings_item_index(const SettingsItemIndex i) { return static_cast<uint8_t>(i); }
 // Use a constexpr function for type-checking.
@@ -123,5 +141,7 @@ constexpr uint8_t settings_item_index(const SettingsItemIndex i) { return static
 const char *translatedString(uint16_t index);
 
 void prepareTranslations();
+bool settings_displayLanguageSwitch(void);
+bool settings_setLanguageSwitch(void);
 
 #endif /* TRANSLATION_H_ */

source/Core/Inc/Translation_multi.h

@@ -0,0 +1,42 @@
+#ifndef TRANSLATION_MULTI_H_
+#define TRANSLATION_MULTI_H_
+
+#include "Translation.h"
+
+// The compressed translation data will be decompressed to this buffer. These
+// data may include:
+//  - TranslationData (translation index table and translation strings)
+//  - Font table(s)
+// The translation index table consists of uint16_t (half words) which has a
+// 2-byte alignment. Therefore, the declaration of this buffer must include
+// the alignment specifier `alignas(TranslationData)` to satisfy its alignment.
+// TranslationData must always be decompressed to the start of this buffer.
+extern uint8_t        translation_data_out_buffer[];
+extern const uint16_t translation_data_out_buffer_size;
+
+struct FontSectionDataInfo {
+  uint16_t symbol_start;
+  uint16_t symbol_count;
+  uint16_t data_size : 15;
+  bool     data_is_compressed : 1;
+
+  // Font12x16 data followed by font6x8 data
+  const uint8_t *data_ptr;
+};
+
+extern const FontSectionDataInfo FontSectionDataInfos[];
+extern const uint8_t             FontSectionDataCount;
+
+extern FontSection DynamicFontSections[];
+
+struct LanguageMeta {
+  char           code[8];
+  const uint8_t *translation_data;
+  uint16_t       translation_size : 15;
+  bool           translation_is_compressed : 1;
+};
+
+extern const LanguageMeta LanguageMetas[];
+extern const uint8_t      LanguageCount;
+
+#endif /* TRANSLATION_MULTI_H_ */