Fixed collection of multiblock directories

Moslty just a hole in testing. Dir blocks were not being
correctly collected when removing entries from very large
files due to forgetting about the tail-bit in the directory
block size. The test hole has now been filled.

Also added lfs_entry_size to avoid having to repeat that
expression since it is a bit ridiculous

lfs.c

@@ -346,6 +346,10 @@ static inline bool lfs_pairsync(
            (paira[0] == pairb[1] && paira[1] == pairb[0]);
 }
 
+static inline lfs_size_t lfs_entry_size(const lfs_entry_t *entry) {
+    return 4 + entry->d.elen + entry->d.alen + entry->d.nlen;
+}
+
 static int lfs_dir_alloc(lfs_t *lfs, lfs_dir_t *dir) {
     // allocate pair of dir blocks
     for (int i = 0; i < 2; i++) {
@@ -571,8 +575,7 @@ static int lfs_dir_append(lfs_t *lfs, lfs_dir_t *dir,
         lfs_entry_t *entry, const void *data) {
     // check if we fit, if top bit is set we do not and move on
     while (true) {
-        if (dir->d.size + 4+entry->d.elen+entry->d.alen+entry->d.nlen
-                <= lfs->cfg->block_size) {
+        if (dir->d.size + lfs_entry_size(entry) <= lfs->cfg->block_size) {
             entry->off = dir->d.size - 4;
             return lfs_dir_commit(lfs, dir, (struct lfs_region[]){
                     {entry->off, 0, &entry->d, sizeof(entry->d)},
@@ -614,7 +617,8 @@ static int lfs_dir_append(lfs_t *lfs, lfs_dir_t *dir,
 
 static int lfs_dir_remove(lfs_t *lfs, lfs_dir_t *dir, lfs_entry_t *entry) {
     // either shift out the one entry or remove the whole dir block
-    if (dir->d.size == sizeof(dir->d)+4) {
+    if ((dir->d.size & 0x7fffffff) == sizeof(dir->d)+4
+            + lfs_entry_size(entry)) {
         lfs_dir_t pdir;
         int res = lfs_pred(lfs, dir->pair, &pdir);
         if (res < 0) {
@@ -623,18 +627,17 @@ static int lfs_dir_remove(lfs_t *lfs, lfs_dir_t *dir, lfs_entry_t *entry) {
 
         if (!(pdir.d.size & 0x80000000)) {
             return lfs_dir_commit(lfs, dir, (struct lfs_region[]){
-                {entry->off, 4+entry->d.elen+entry->d.alen+entry->d.nlen,
-                 NULL, 0},
+                {entry->off, lfs_entry_size(entry), NULL, 0},
             }, 1);
         } else {
+            pdir.d.size &= dir->d.size | 0x7fffffff;
             pdir.d.tail[0] = dir->d.tail[0];
             pdir.d.tail[1] = dir->d.tail[1];
-            return lfs_dir_commit(lfs, dir, NULL, 0);
+            return lfs_dir_commit(lfs, &pdir, NULL, 0);
         }
     } else {
         return lfs_dir_commit(lfs, dir, (struct lfs_region[]){
-            {entry->off, 4+entry->d.elen+entry->d.alen+entry->d.nlen,
-             NULL, 0},
+            {entry->off, lfs_entry_size(entry), NULL, 0},
         }, 1);
     }
 }
@@ -662,8 +665,8 @@ static int lfs_dir_next(lfs_t *lfs, lfs_dir_t *dir, lfs_entry_t *entry) {
     }
 
     entry->off = dir->off;
-    dir->off += 4+entry->d.elen+entry->d.alen+entry->d.nlen;
-    dir->pos += 4+entry->d.elen+entry->d.alen+entry->d.nlen;
+    dir->off += lfs_entry_size(entry);
+    dir->pos += lfs_entry_size(entry);
     return 0;
 }
 
@@ -1635,7 +1638,7 @@ int lfs_remove(lfs_t *lfs, const char *path) {
                 f->pair[0] = 0xffffffff;
                 f->pair[1] = 0xffffffff;
             } else if (f->poff > entry.off) {
-                f->poff -= 4 + entry.d.elen + entry.d.alen + entry.d.nlen;
+                f->poff -= lfs_entry_size(&entry);
             }
         }
     }
@@ -1739,7 +1742,7 @@ int lfs_rename(lfs_t *lfs, const char *oldpath, const char *newpath) {
                 f->pair[0] = 0xffffffff;
                 f->pair[1] = 0xffffffff;
             } else if (f->poff > oldentry.off) {
-                f->poff -= 4+oldentry.d.elen+oldentry.d.alen+oldentry.d.nlen;
+                f->poff -= lfs_entry_size(&oldentry);
             }
         }
     }
@@ -1974,7 +1977,7 @@ int lfs_traverse(lfs_t *lfs, int (*cb)(void*, lfs_block_t), void *data) {
                 return err;
             }
 
-            dir.off += 4+entry.d.elen+entry.d.alen+entry.d.nlen;
+            dir.off += lfs_entry_size(&entry);
             if ((0xf & entry.d.type) == (0xf & LFS_TYPE_REG)) {
                 int err = lfs_index_traverse(lfs, &lfs->rcache, NULL,
                         entry.d.u.file.head, entry.d.u.file.size, cb, data);

tests/test_dirs.sh

@@ -124,7 +124,6 @@ tests/test.py << TEST
 TEST
 
 echo "--- Directory remove ---"
-# TESTING HERE
 tests/test.py << TEST
     lfs_mount(&lfs, &cfg) => 0;
     lfs_remove(&lfs, "potato") => LFS_ERR_INVAL;
@@ -283,5 +282,38 @@ tests/test.py << TEST
     lfs_unmount(&lfs) => 0;
 TEST
 
+echo "--- Multi-block remove ---"
+tests/test.py << TEST
+    lfs_mount(&lfs, &cfg) => 0;
+    lfs_remove(&lfs, "cactus") => LFS_ERR_INVAL;
+
+    for (int i = 0; i < $LARGESIZE; i++) {
+        sprintf((char*)buffer, "cactus/test%d", i);
+        lfs_remove(&lfs, (char*)buffer) => 0;
+    }
+
+    lfs_remove(&lfs, "cactus") => 0;
+    lfs_unmount(&lfs) => 0;
+TEST
+tests/test.py << TEST
+    lfs_mount(&lfs, &cfg) => 0;
+    lfs_dir_open(&lfs, &dir[0], "/") => 0;
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, ".") => 0;
+    info.type => LFS_TYPE_DIR;
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, "..") => 0;
+    info.type => LFS_TYPE_DIR;
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, "burito") => 0;
+    info.type => LFS_TYPE_REG;
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, "coldpotato") => 0;
+    info.type => LFS_TYPE_DIR;
+    lfs_dir_read(&lfs, &dir[0], &info) => 0;
+    lfs_dir_close(&lfs, &dir[0]) => 0;
+    lfs_unmount(&lfs) => 0;
+TEST
+
 echo "--- Results ---"
 tests/stats.py