feat: (iso9660) directory read support

[lunaix-os.git] / lunaix-os / kernel / fs / iso9660 / directory.c

diff --git a/lunaix-os/kernel/fs/iso9660/directory.c b/lunaix-os/kernel/fs/iso9660/directory.c
new file mode 100644 (file)
index 0000000..d240e1f
--- /dev/null
+++ b/lunaix-os/kernel/fs/iso9660/directory.c
@@ -0,0 +1,148 @@
+#include <lunaix/dirent.h>
+#include <lunaix/fs.h>
+#include <lunaix/fs/iso9660.h>
+#include <lunaix/mm/cake.h>
+#include <lunaix/mm/valloc.h>
+#include <lunaix/spike.h>
+
+#include <klibc/string.h>
+
+extern struct cake_pile* drec_cache_pile;
+
+void
+iso9660_fill_drecache(struct iso_drecache* cache, struct iso_drecord* drec)
+{
+    *cache = (struct iso_drecache){ .data_size = drec->data_size.le,
+                                    .extent_addr = drec->extent_addr.le,
+                                    .flags = drec->flags,
+                                    .fu_size = drec->fu_sz ? drec->fu_sz : 1,
+                                    .gap_size = drec->gap_sz,
+                                    .xattr_len = drec->xattr_len };
+    u32_t l = drec->name.len;
+    while (l < (u32_t)-1 && drec->name.content[l--] != ';')
+        ;
+    l = (l + 1) ? l : drec->name.len;
+    l = MIN(l, ISO9660_IDLEN);
+    strncpy(cache->name_val, drec->name.content, l);
+    cache->name = HSTR(cache->name_val, l);
+    hstr_rehash(&cache->name, HSTR_FULL_HASH);
+}
+
+int
+iso9660_setup_dnode(struct v_dnode* dnode, struct v_inode* inode)
+{
+    if (!(inode->itype & VFS_IFDIR)) {
+        return;
+    }
+
+    int errno = 0;
+    struct device* dev = dnode->super_block->dev;
+    struct iso_inode* isoino = inode->data;
+    struct llist_header* lead = valloc(sizeof(*lead));
+    void* records = valloc(ISO9660_BLKSZ);
+    u32_t current_pos = -ISO9660_BLKSZ, max_pos = inode->fsize,
+          blk = inode->lb_addr * ISO9660_BLKSZ, blk_offset = (u32_t)-1;
+
+    llist_init_head(lead);
+
+    // As per 6.8.1, Directory structure shall NOT recorded in interleave mode.
+    do {
+        if (blk_offset >= ISO9660_BLKSZ - sizeof(struct iso_drecord)) {
+            current_pos += ISO9660_BLKSZ;
+            errno = dev->read(dev, records, blk + current_pos, ISO9660_BLKSZ);
+            if (errno < 0) {
+                errno = EIO;
+                goto done;
+            }
+            blk_offset = 0;
+        }
+
+        struct iso_drecord* drec;
+        struct iso_var_mdu* mdu = (struct iso_var_mdu*)(records + blk_offset);
+
+        if (!(drec = iso9660_get_drecord(mdu))) {
+            break;
+        }
+
+        // ignore the '.', '..' as we have built-in support
+        if (drec->name.len == 1) {
+            goto cont;
+        }
+
+        struct iso_drecache* cache = cake_grab(drec_cache_pile);
+
+        iso9660_fill_drecache(cache, drec);
+        llist_append(lead, &cache->caches);
+    cont:
+        blk_offset += mdu->len;
+    } while (current_pos + blk_offset < max_pos);
+
+    dnode->data = lead;
+    isoino->drecaches = lead;
+
+    vfs_assign_inode(dnode, inode);
+
+    errno = 0;
+
+done:
+    vfree(records);
+    return errno;
+}
+
+int
+iso9660_dir_lookup(struct v_inode* this, struct v_dnode* dnode)
+{
+    struct iso_inode* isoino = this->data;
+    struct llist_header* lead = isoino->drecaches;
+    struct iso_drecache *pos, *n;
+
+    llist_for_each(pos, n, lead, caches)
+    {
+        if (HSTR_EQ(&dnode->name, &pos->name)) {
+            goto found;
+        }
+    }
+
+    return ENOENT;
+found:
+    struct v_inode* inode = vfs_i_find(dnode->super_block, pos->extent_addr);
+
+    if (!inode) {
+        inode = vfs_i_alloc(dnode->super_block);
+        iso9660_fill_inode(inode, pos, pos->extent_addr);
+        vfs_i_addhash(inode);
+    }
+
+    iso9660_setup_dnode(dnode, inode);
+
+    return 0;
+}
+
+static int
+__get_dtype(struct iso_drecache* pos)
+{
+    if ((pos->flags & ISO_FDIR)) {
+        return DT_DIR;
+    } else {
+        return DT_FILE;
+    }
+}
+
+int
+iso9660_readdir(struct v_file* file, struct dir_context* dctx)
+{
+    struct llist_header* lead = file->dnode->data;
+    struct iso_drecache *pos, *n;
+    u32_t counter = dctx->index - 1;
+
+    llist_for_each(pos, n, lead, caches)
+    {
+        if (counter == (u32_t)-1 && !(pos->flags & ISO_FHIDDEN)) {
+            dctx->read_complete_callback(
+              dctx, pos->name_val, pos->name.len, __get_dtype(pos));
+            return 1;
+        }
+        counter--;
+    }
+    return 0;
+}
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