Adopted lazy geometry encoding

- LFSR_TAG_GEOMETRY ---> lfsr_data_fromgeometry

Not much to say about this one, LFSR_TAG_GEOMETRY is a bit of an
outlier.

I did consider deduplicating with the mptr encoder, but decided that
would be too hacky, and create problems for future metadata redundancy
things.

Still saves code though, which is nice:

           code          stack          ctx
  before: 35632           2440          636
  after:  35580 (-0.1%)   2440 (+0.0%)  636 (+0.0%)

lfs.c

@@ -3449,6 +3449,9 @@ static int lfsr_rbyd_appendtag(lfs_t *lfs, lfsr_rbyd_t *rbyd,
 }
 
 // needed in lfsr_rbyd_appendrattr_
+typedef struct lfsr_geometry lfsr_geometry_t;
+static lfsr_data_t lfsr_data_fromgeometry(const lfsr_geometry_t *geometry,
+        uint8_t buffer[static LFSR_GEOMETRY_DSIZE]);
 static lfsr_data_t lfsr_data_frombptr(const lfsr_bptr_t *bptr,
         uint8_t buffer[static LFSR_BPTR_DSIZE]);
 static lfsr_data_t lfsr_data_fromshrub(const lfsr_shrub_t *shrub,
@@ -3473,6 +3476,8 @@ static int lfsr_rbyd_appendrattr_(lfs_t *lfs, lfsr_rbyd_t *rbyd,
             LFSR_LE32_DSIZE,
             LFS_MAX(
                 LFSR_LEB128_DSIZE,
+                LFS_MAX(
+                    LFSR_GEOMETRY_DSIZE,
                     LFS_MAX(
                         LFSR_BPTR_DSIZE,
                         LFS_MAX(
@@ -3481,7 +3486,7 @@ static int lfsr_rbyd_appendrattr_(lfs_t *lfs, lfsr_rbyd_t *rbyd,
                                 LFSR_BTREE_DSIZE,
                                 LFS_MAX(
                                     LFSR_MPTR_DSIZE,
-                                LFSR_ECKSUM_DSIZE))))))];
+                                    LFSR_ECKSUM_DSIZE)))))))];
     switch (lfsr_rattr_dtag(rattr)) {
     // le32?
     case LFSR_TAG_RCOMPAT:;
@@ -3505,6 +3510,14 @@ static int lfsr_rbyd_appendrattr_(lfs_t *lfs, lfsr_rbyd_t *rbyd,
         data_count = size;
         break;
 
+    // geometry?
+    case LFSR_TAG_GEOMETRY:;
+        data = lfsr_data_fromgeometry(rattr.u.etc, buf);
+        size = lfsr_data_size(data);
+        datas = buf;
+        data_count = size;
+        break;
+
     // bptr?
     case LFSR_TAG_BLOCK:;
     case LFSR_TAG_SHRUB | LFSR_TAG_BLOCK:;
@@ -13310,10 +13323,10 @@ static inline int lfsr_data_readocompat(lfs_t *lfs, lfsr_data_t *data,
 // disk geometry
 //
 // note these are stored minus 1 to avoid overflow issues
-typedef struct lfsr_geometry {
+struct lfsr_geometry {
     lfs_off_t block_size;
     lfs_off_t block_count;
-} lfsr_geometry_t;
+};
 
 // geometry on-disk encoding
 static lfsr_data_t lfsr_data_fromgeometry(const lfsr_geometry_t *geometry,
@@ -13841,7 +13854,6 @@ static int lfsr_formatinited(lfs_t *lfs) {
         // - our magic string, "littlefs"
         // - any format-time configuration
         // - the root's bookmark tag, which reserves did = 0 for the root
-        uint8_t geometry_buf[LFSR_GEOMETRY_DSIZE];
         err = lfsr_rbyd_appendrattrs(lfs, &rbyd, -1, -1, -1, LFSR_RATTRS(
                 LFSR_RATTR(
                     LFSR_TAG_MAGIC, 0,
@@ -13857,13 +13869,11 @@ static int lfsr_formatinited(lfs_t *lfs) {
                 LFSR_RATTR_LE32__(
                     LFSR_TAG_WCOMPAT, 0,
                     LFSR_WCOMPAT_COMPAT),
-                LFSR_RATTR(
+                LFSR_RATTR__(
                     LFSR_TAG_GEOMETRY, 0,
-                    LFSR_DATA_GEOMETRY(
                     (&(lfsr_geometry_t){
                         lfs->cfg->block_size,
-                            lfs->cfg->block_count}),
+                        lfs->cfg->block_count}), LFSR_GEOMETRY_DSIZE),
-                        geometry_buf)),
                 LFSR_RATTR_LEB128__(
                     LFSR_TAG_NAMELIMIT, 0,
                     lfs->name_limit),
@@ -14386,15 +14396,12 @@ int lfsr_fs_grow(lfs_t *lfs, lfs_size_t block_count_) {
 
     // update our on-disk config
     lfs_alloc_ckpoint(lfs);
-    uint8_t geometry_buf[LFSR_GEOMETRY_DSIZE];
     int err = lfsr_mdir_commit(lfs, &lfs->mroot, LFSR_RATTRS(
-            LFSR_RATTR(
+            LFSR_RATTR__(
                 LFSR_TAG_GEOMETRY, 0,
-                LFSR_DATA_GEOMETRY(
                 (&(lfsr_geometry_t){
                     lfs->cfg->block_size,
-                        block_count_}),
+                    block_count_}), LFSR_GEOMETRY_DSIZE)));
-                    geometry_buf))));
     if (err) {
         goto failed;
     }

tests/test_mount.toml

@@ -995,15 +995,12 @@ code = '''
     // note we're messing around with internals to do this! this
     // is not a user API
     lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
-    uint8_t geometry_buf[LFSR_GEOMETRY_DSIZE];
     lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_RATTRS(
-            LFSR_RATTR(
+            LFSR_RATTR__(
                 LFSR_TAG_GEOMETRY, 0,
-                LFSR_DATA_GEOMETRY(
                 (&(lfsr_geometry_t){
                     INC_BLOCK_SIZE,
-                        BLOCK_COUNT}),
+                    BLOCK_COUNT}), LFSR_GEOMETRY_DSIZE))) => 0;
-                    geometry_buf)))) => 0;
     lfsr_unmount(&lfs) => 0;
 
     // mount should now fail
@@ -1025,15 +1022,12 @@ code = '''
     // note we're messing around with internals to do this! this
     // is not a user API
     lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
-    uint8_t geometry_buf[LFSR_GEOMETRY_DSIZE];
     lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_RATTRS(
-            LFSR_RATTR(
+            LFSR_RATTR__(
                 LFSR_TAG_GEOMETRY, 0,
-                LFSR_DATA_GEOMETRY(
                 (&(lfsr_geometry_t){
                     BLOCK_SIZE,
-                        INC_BLOCK_COUNT}),
+                    INC_BLOCK_COUNT}), LFSR_GEOMETRY_DSIZE))) => 0;
-                    geometry_buf)))) => 0;
     lfsr_unmount(&lfs) => 0;
 
     // mount should now fail