Dropped lfsr_data_t hole representation

We don't need this, it's not easily gc-able, and encourages redundant
lookups. It's better to just handle holes explicitly where needed.

lfs.c

@@ -990,9 +990,8 @@ static lfs_ssize_t lfsr_bd_progtag(lfs_t *lfs,
 // in-device data modes
 enum {
     LFSR_DATA_BUF   = 0,
-    LFSR_DATA_HOLE  = 1,
+    LFSR_DATA_IMM   = 1,
-    LFSR_DATA_IMM   = 2,
+    LFSR_DATA_CAT   = 2,
-    LFSR_DATA_CAT   = 3,
 };
 
 // LFSR_DATA_DATA just provides and escape hatch to pass raw datas
@@ -1017,11 +1016,6 @@ enum {
         .u.buf.mode=LFSR_DATA_BUF, \
         .u.buf.buffer=(const void*)(_buffer)})
 
-#define LFSR_DATA_HOLE(_size) \
-    ((lfsr_data_t){ \
-        .u.hole.size=_size, \
-        .u.hole.mode=LFSR_DATA_HOLE})
-
 #define LFSR_DATA_IMM(_buffer, _size) \
     lfsr_data_fromimm(_buffer, _size)
 
@@ -1065,10 +1059,6 @@ static inline bool lfsr_data_isbuf(const lfsr_data_t *data) {
     return !lfsr_data_ondisk(data) && data->u.buf.mode == LFSR_DATA_BUF;
 }
 
-static inline bool lfsr_data_ishole(const lfsr_data_t *data) {
-    return !lfsr_data_ondisk(data) && data->u.buf.mode == LFSR_DATA_HOLE;
-}
-
 static inline bool lfsr_data_isimm(const lfsr_data_t *data) {
     return !lfsr_data_ondisk(data) && data->u.buf.mode == LFSR_DATA_IMM;
 }
@@ -1143,10 +1133,6 @@ static lfsr_data_t lfsr_data_slice(lfsr_data_t data,
         data.u.buf.buffer += off_;
         data.u.buf.size = size_;
 
-    // hole? decrement
-    } else if (lfsr_data_ishole(&data)) {
-        data.u.hole.size = size_;
-
     // inlined? internal memmove
     } else if (lfsr_data_isimm(&data)) {
         memmove(data.u.imm.buf,
@@ -1199,10 +1185,6 @@ static lfs_ssize_t lfsr_data_read(lfs_t *lfs, lfsr_data_t *data,
     } else if (lfsr_data_isbuf(data)) {
         memcpy(buffer, data->u.buf.buffer, d);
 
-    // hole?
-    } else if (lfsr_data_ishole(data)) {
-        memset(buffer, 0, d);
-
     // inlined?
     } else if (lfsr_data_isimm(data)) {
         memcpy(buffer, data->u.imm.buf, d);
@@ -1277,22 +1259,6 @@ static lfs_scmp_t lfsr_data_cmp(lfs_t *lfs, const lfsr_data_t *data,
             return LFS_CMP_GT;
         }
 
-    // hole?
-    } else if (lfsr_data_ishole(data)) {
-        const uint8_t *buffer_ = buffer;
-        int cmp = 0;
-        if (d > 0) {
-            cmp = buffer_[0] - 0;
-            if (cmp == 0) {
-                cmp = memcmp(buffer_, buffer_+1, size-1);
-            }
-        }
-        if (cmp < 0) {
-            return LFS_CMP_LT;
-        } else if (cmp > 0) {
-            return LFS_CMP_GT;
-        }
-
     // inlined?
     } else if (lfsr_data_isimm(data)) {
         int cmp = memcmp(data->u.imm.buf, buffer, d);
@@ -1371,17 +1337,6 @@ static int lfsr_bd_progdata_(lfs_t *lfs,
             return err;
         }
 
-    // hole?
-    } else if (lfsr_data_ishole(&data)) {
-        // TODO do something better than byte-level progs here
-        for (lfs_size_t i = 0; i < lfsr_data_size(&data); i++) {
-            int err = lfsr_bd_prog(lfs, block, off+i, &(uint8_t){0}, 1,
-                    cksum_);
-            if (err) {
-                return err;
-            }
-        }
-
     // inlined?
     } else if (lfsr_data_isimm(&data)) {
         int err = lfsr_bd_prog(lfs, block, off,

lfs.h

@@ -420,7 +420,6 @@ typedef struct lfs_mdir {
 // The exact representation of in-device data also depends on the
 // mode field:
 // - pointer to a RAM-backed buffer
-// - implicitly zero-filled holes
 // - inlined data able to fit at least 1 leb128
 // - an array of concatenated datas
 //
@@ -440,10 +439,6 @@ typedef struct lfsr_data {
             uint8_t mode;
             const uint8_t *buffer;
         } buf;
-        struct {
-            lfs_ssize_t size;
-            uint8_t mode;
-        } hole;
         struct {
             lfs_ssize_t size;
             uint8_t mode;