Update to the latest SPIFFS git and cleanup

Almost unmodified spiffs from github
lots of NodeMCU leftovers are removed
More proper names given to platform related files
Adjusting the FS class for the changes

cores/esp8266/spiffs/spiffs_nucleus.h

@@ -131,6 +131,10 @@
 #define SPIFFS_OBJ_ID_DELETED           ((spiffs_obj_id)0)
 #define SPIFFS_OBJ_ID_FREE              ((spiffs_obj_id)-1)
 
+#define SPIFFS_MAGIC(fs)                ((spiffs_obj_id)(0x20140529 ^ SPIFFS_CFG_LOG_PAGE_SZ(fs)))
+
+#define SPIFFS_CONFIG_MAGIC             (0x20090315)
+
 #if SPIFFS_SINGLETON == 0
 #define SPIFFS_CFG_LOG_PAGE_SZ(fs) \
   ((fs)->cfg.log_page_size)
@@ -189,9 +193,18 @@
 // returns data size in a data page
 #define SPIFFS_DATA_PAGE_SIZE(fs) \
     ( SPIFFS_CFG_LOG_PAGE_SZ(fs) - sizeof(spiffs_page_header) )
-// returns physical address for block's erase count
+// returns physical address for block's erase count,
+// always in the physical last entry of the last object lookup page
 #define SPIFFS_ERASE_COUNT_PADDR(fs, bix) \
   ( SPIFFS_BLOCK_TO_PADDR(fs, bix) + SPIFFS_OBJ_LOOKUP_PAGES(fs) * SPIFFS_CFG_LOG_PAGE_SZ(fs) - sizeof(spiffs_obj_id) )
+// returns physical address for block's magic,
+// always in the physical second last entry of the last object lookup page
+#define SPIFFS_MAGIC_PADDR(fs, bix) \
+  ( SPIFFS_BLOCK_TO_PADDR(fs, bix) + SPIFFS_OBJ_LOOKUP_PAGES(fs) * SPIFFS_CFG_LOG_PAGE_SZ(fs) - sizeof(spiffs_obj_id)*2 )
+// checks if there is any room for magic in the object luts
+#define SPIFFS_CHECK_MAGIC_POSSIBLE(fs) \
+  ( (SPIFFS_OBJ_LOOKUP_MAX_ENTRIES(fs) % (SPIFFS_CFG_LOG_PAGE_SZ(fs)/sizeof(spiffs_obj_id))) * sizeof(spiffs_obj_id) \
+    <= (SPIFFS_CFG_LOG_PAGE_SZ(fs)-sizeof(spiffs_obj_id)*2) )
 
 // define helpers object
 
@@ -238,7 +251,10 @@
 
 
 #define SPIFFS_CHECK_MOUNT(fs) \
-  ((fs)->block_count > 0)
+  ((fs)->mounted != 0)
+
+#define SPIFFS_CHECK_CFG(fs) \
+  ((fs)->config_magic == SPIFFS_CONFIG_MAGIC)
 
 #define SPIFFS_CHECK_RES(res) \
   do { \
@@ -247,19 +263,25 @@
 
 #define SPIFFS_API_CHECK_MOUNT(fs) \
   if (!SPIFFS_CHECK_MOUNT((fs))) { \
-    (fs)->errno = SPIFFS_ERR_NOT_MOUNTED; \
+    (fs)->err_code = SPIFFS_ERR_NOT_MOUNTED; \
+    return -1; \
+  }
+
+#define SPIFFS_API_CHECK_CFG(fs) \
+  if (!SPIFFS_CHECK_CFG((fs))) { \
+    (fs)->err_code = SPIFFS_ERR_NOT_CONFIGURED; \
     return -1; \
   }
 
 #define SPIFFS_API_CHECK_RES(fs, res) \
   if ((res) < SPIFFS_OK) { \
-    (fs)->errno = (res); \
+    (fs)->err_code = (res); \
     return -1; \
   }
 
 #define SPIFFS_API_CHECK_RES_UNLOCK(fs, res) \
   if ((res) < SPIFFS_OK) { \
-    (fs)->errno = (res); \
+    (fs)->err_code = (res); \
     SPIFFS_UNLOCK(fs); \
     return -1; \
   }
@@ -381,6 +403,8 @@ typedef struct {
 // object structs
 
 // page header, part of each page except object lookup pages
+// NB: this is always aligned when the data page is an object index,
+// as in this case struct spiffs_page_object_ix is used
 typedef struct __attribute(( packed )) {
   // object id
   spiffs_obj_id obj_id;
@@ -391,7 +415,11 @@ typedef struct __attribute(( packed )) {
 } spiffs_page_header;
 
 // object index header page header
-typedef struct __attribute(( packed )) {
+typedef struct __attribute(( packed ))
+#if SPIFFS_ALIGNED_OBJECT_INDEX_TABLES
+                __attribute(( aligned(sizeof(spiffs_page_ix)) ))
+#endif
+{
   // common page header
   spiffs_page_header p_hdr;
   // alignment
@@ -400,8 +428,6 @@ typedef struct __attribute(( packed )) {
   u32_t size;
   // type of object
   spiffs_obj_type type;
-  // alignment2
-  u8_t _align2[4 - (sizeof(spiffs_obj_type)&3)==0 ? 4 : (sizeof(spiffs_obj_type)&3)];
   // name of object
   u8_t name[SPIFFS_OBJ_NAME_LEN];
 } spiffs_page_object_ix_header;
@@ -480,6 +506,10 @@ s32_t spiffs_obj_lu_find_entry_visitor(
     spiffs_block_ix *block_ix,
     int *lu_entry);
 
+s32_t spiffs_erase_block(
+    spiffs *fs,
+    spiffs_block_ix bix);
+
 // ---------------
 
 s32_t spiffs_obj_lu_scan(
@@ -627,7 +657,8 @@ s32_t spiffs_gc_erase_page_stats(
 s32_t spiffs_gc_find_candidate(
     spiffs *fs,
     spiffs_block_ix **block_candidate,
-    int *candidate_count);
+    int *candidate_count,
+    char fs_crammed);
 
 s32_t spiffs_gc_clean(
     spiffs *fs,