Changeset 32fb10ed in mainline

Timestamp:

2008-04-12T23:13:51Z (17 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

9ad75d5

Parents:

74ea3c6

Message:

Add fat_has_children(). Alse assume that fat_block_get() can never return NULL.

File:

• uspace/srv/fs/fat/fat_ops.c (modified) (6 diffs)

uspace/srv/fs/fat/fat_ops.c

@@ -144 +144 @@
 }
 
+typedef enum {
+        FAT_DENTRY_SKIP,
+        FAT_DENTRY_LAST,
+        FAT_DENTRY_VALID
+} fat_dentry_clsf_t;
+
+static fat_dentry_clsf_t fat_classify_dentry(fat_dentry_t *d)
+{
+        if (d->attr & FAT_ATTR_VOLLABEL) {
+                /* volume label entry */
+                return FAT_DENTRY_SKIP;
+        }
+        if (d->name[0] == FAT_DENTRY_ERASED) {
+                /* not-currently-used entry */
+                return FAT_DENTRY_SKIP;
+        }
+        if (d->name[0] == FAT_DENTRY_UNUSED) {
+                /* never used entry */
+                return FAT_DENTRY_LAST;
+        }
+        if (d->name[0] == FAT_DENTRY_DOT) {
+                /*
+                 * Most likely '.' or '..'.
+                 * It cannot occur in a regular file name.
+                 */
+                return FAT_DENTRY_SKIP;
+        }
+        return FAT_DENTRY_VALID;
+}
+
 static void fat_sync_node(fat_node_t *node)
 {
@@ -222 +252 @@
         for (i = 0; ; i++) {
                 b = fat_block_get(node->dev_handle, node->pindex, i);
-                if (!b) {
-                        node->refcnt--;
-                        list_append(&node->ffn_link, &ffn_head);
-                        return NULL;
-                }
                 for (j = 0; j < dps; j++) {
                         d = ((fat_dentry_t *)b->data) + j;
@@ -270 +295 @@
                 
                 b = fat_block_get(parentp->dev_handle, parentp->index, i);
-                if (!b) 
-                        return NULL;
-
                 dentries = (i == blocks - 1) ?
                     parentp->size % sizeof(fat_dentry_t) :
@@ -278 +300 @@
                 for (j = 0; j < dentries; j++) { 
                         d = ((fat_dentry_t *)b->data) + j;
-                        if (d->attr & FAT_ATTR_VOLLABEL) {
-                                /* volume label entry */
+                        switch (fat_classify_dentry(d)) {
+                        case FAT_DENTRY_SKIP:
                                 continue;
-                        }
-                        if (d->name[0] == FAT_DENTRY_ERASED) {
-                                /* not-currently-used entry */
-                                continue;
-                        }
-                        if (d->name[0] == FAT_DENTRY_UNUSED) {
-                                /* never used entry */
+                        case FAT_DENTRY_LAST:
                                 block_put(b);
                                 return NULL;
+                        default:
+                        case FAT_DENTRY_VALID:
+                                dentry_name_canonify(d, name);
+                                break;
                         }
-                        if (d->name[0] == FAT_DENTRY_DOT) {
-                                /*
-                                 * Most likely '.' or '..'.
-                                 * It cannot occur in a regular file name.
-                                 */
-                                continue;
-                        }
-                
-                        dentry_name_canonify(d, name);
                         if (strcmp(name, component) == 0) {
                                 /* hit */
@@ -331 +342 @@
 {
         return ((fat_node_t *)node)->lnkcnt;
+}
+
+static bool fat_has_children(void *node)
+{
+        fat_node_t *nodep = (fat_node_t *)node;
+        unsigned bps;
+        unsigned dps;
+        unsigned blocks;
+        block_t *b;
+        unsigned i, j;
+
+        if (nodep->type != FAT_DIRECTORY)
+                return false;
+
+        bps = fat_bps_get(nodep->dev_handle);
+        dps = bps / sizeof(fat_dentry_t);
+
+        blocks = nodep->size / bps + (nodep->size % bps != 0);
+
+        for (i = 0; i < blocks; i++) {
+                unsigned dentries;
+                fat_dentry_t *d;
+        
+                b = fat_block_get(nodep->dev_handle, nodep->index, i);
+                dentries = (i == blocks - 1) ?
+                    nodep->size % sizeof(fat_dentry_t) :
+                    dps;
+                for (j = 0; j < dentries; j++) {
+                        d = ((fat_dentry_t *)b->data) + j;
+                        switch (fat_classify_dentry(d)) {
+                        case FAT_DENTRY_SKIP:
+                                continue;
+                        case FAT_DENTRY_LAST:
+                                block_put(b);
+                                return false;
+                        default:
+                        case FAT_DENTRY_VALID:
+                                block_put(b);
+                                return true;
+                        }
+                        block_put(b);
+                        return true;
+                }
+                block_put(b);
+        }
+
+        return false;
 }
 
@@ -364 +422 @@
         .size_get = fat_size_get,
         .lnkcnt_get = fat_lnkcnt_get,
-        .has_children = NULL,
+        .has_children = fat_has_children,
         .root_get = fat_root_get,
         .plb_get_char = fat_plb_get_char,