WebSVN – HelenOS – Diff – /trunk/uspace/srv/fs/fat/fat_ops.c

 /*
  * Copyright (c) 2008 Jakub Jermar
  * All rights reserved.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
+ *
  * - Redistributions of source code must retain the above copyright
  *   notice, this list of conditions and the following disclaimer.
  * - Redistributions in binary form must reproduce the above copyright
  *   notice, this list of conditions and the following disclaimer in the
  *   documentation and/or other materials provided with the distribution.
  * - The name of the author may not be used to endorse or promote products
  *   derived from this software without specific prior written permission.
+ *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 /** @addtogroup fs
  * @{
  */
 /**
  * @file    fat_ops.c
  * @brief   Implementation of VFS operations for the FAT file system server.
  */
 #include "fat.h"
 #include "../../vfs/vfs.h"
 #include <libfs.h>
 #include <ipc/ipc.h>
 #include <async.h>
 #include <errno.h>
 #include <string.h>
 #include <byteorder.h>
 #define FAT_NAME_LEN        8
 #define FAT_EXT_LEN     3
 #define FAT_PAD         ' '
 #define FAT_DENTRY_UNUSED   0x00
 #define FAT_DENTRY_E5_ESC   0x05
 #define FAT_DENTRY_DOT      0x2e
 #define FAT_DENTRY_ERASED   0xe5
 static void dentry_name_canonify(fat_dentry_t *d, char *buf)
+{
     int i;
     for (i = 0; i < FAT_NAME_LEN; i++) {
         if (d->name[i] == FAT_PAD) {
             buf++;
             break;
+        }
         if (d->name[i] == FAT_DENTRY_E5_ESC)
             *buf++ = 0xe5;
         else
             *buf++ = d->name[i];
+    }
     if (d->ext[0] != FAT_PAD)
         *buf++ = '.';
     for (i = 0; i < FAT_EXT_LEN; i++) {
         if (d->ext[i] == FAT_PAD) {
             *buf = '\0';
             return;
+        }
         if (d->ext[i] == FAT_DENTRY_E5_ESC)
             *buf++ = 0xe5;
         else
             *buf++ = d->ext[i];
+    }
+}
+/* TODO and also move somewhere else */
+typedef struct {
+    void *data;
+} block_t;
-static fat_dentry_t *fat_dentry_get(fat_node_t *dirnode, unsigned idx)
+static block_t *block_get(dev_handle_t dev_handle, off_t offset)
+{
     return NULL;    /* TODO */
+}
+static block_t *fat_block_get(fat_node_t *node, off_t offset) {
+    return NULL;    /* TODO */
+}
-static void fat_dentry_put(fat_dentry_t *dentry)
+static void block_put(block_t *block)
+{
     /* TODO */
+}
 static void *fat_node_get(dev_handle_t dev_handle, fs_index_t index)
+{
     return NULL;    /* TODO */
+}
+#define BS_BLOCK    0
 static void *fat_match(void *prnt, const char *component)
+{
     fat_node_t *parentp = (fat_node_t *)prnt;
     char name[FAT_NAME_LEN + 1 + FAT_EXT_LEN + 1];
-    unsigned i;
+    unsigned i, j;
+    unsigned dps;       /* dentries per sector */
-    unsigned dentries;
+    unsigned blocks;
     fat_dentry_t *d;
+    block_t *bb;
+    block_t *b;
+    fat_bs_t *bs;
+    bb = block_get(parentp->dev_handle, BS_BLOCK);
+    if (!bb)
+        return NULL;
+    bs = (fat_bs_t *)bb->data;
-    dentries = parentp->size / sizeof(fat_dentry_t);
+    dps = bs->bps / sizeof(fat_dentry_t);
+    blocks = parentp->size / bs->bps + (parentp->size % bs->bps != 0);
+    block_put(bb);
-    for (i = 0; i < dentries; i++) {
+    for (i = 0; i < blocks; i++) {
+        unsigned dentries;
-        d = fat_dentry_get(parentp, i);
+        b = fat_block_get(parentp, i);
+        if (!b)
+            return NULL;
+        dentries = (i == blocks - 1) ?
+            parentp->size % sizeof(fat_dentry_t) :
+            dps;
+        for (j = 0; j < dentries; j++) {
+            d = ((fat_dentry_t *)b->data) + j;
-        if (d->attr & FAT_ATTR_VOLLABEL) {
+            if (d->attr & FAT_ATTR_VOLLABEL) {
-            /* volume label entry */
+                /* volume label entry */
-            fat_dentry_put(d);
-            continue;
+                continue;
-        }
+            }
-        if (d->name[0] == FAT_DENTRY_ERASED) {
+            if (d->name[0] == FAT_DENTRY_ERASED) {
-            /* not-currently-used entry */
+                /* not-currently-used entry */
-            fat_dentry_put(d);
-            continue;
+                continue;
-        }
+            }
-        if (d->name[0] == FAT_DENTRY_UNUSED) {
+            if (d->name[0] == FAT_DENTRY_UNUSED) {
-            /* never used entry */
+                /* never used entry */
-            fat_dentry_put(d);
+                block_put(b);
-            break;
+                return NULL;
-        }
+            }
-        if (d->name[0] == FAT_DENTRY_DOT) {
+            if (d->name[0] == FAT_DENTRY_DOT) {
-            /*
+                /*
-             * Most likely '.' or '..'.
+                 * Most likely '.' or '..'.
-             * It cannot occur in a regular file name.
+                 * It cannot occur in a regular file name.
-             */
+                 */
-            fat_dentry_put(d);
-            continue;
+                continue;
-        }
+            }
-        dentry_name_canonify(d, name);
+            dentry_name_canonify(d, name);
-        if (strcmp(name, component) == 0) {
+            if (strcmp(name, component) == 0) {
-            /* hit */
+                /* hit */
-            void *node = fat_node_get(parentp->dev_handle,
+                void *node = fat_node_get(parentp->dev_handle,
-                (fs_index_t)uint16_t_le2host(d->firstc));
+                    (fs_index_t)uint16_t_le2host(d->firstc));
-            fat_dentry_put(d);
+                block_put(b);
-            return node;
+                return node;
-        } else {
+            }
-            /* miss */
-            fat_dentry_put(d);
+        }
+        block_put(b);
+    }
     return NULL;
+}
 /** libfs operations */
 libfs_ops_t fat_libfs_ops = {
     .match = fat_match,
     .node_get = fat_node_get,
     .create = NULL,
     .destroy = NULL,
     .link = NULL,
     .unlink = NULL,
     .index_get = NULL,
     .size_get = NULL,
     .lnkcnt_get = NULL,
     .has_children = NULL,
     .root_get = NULL,
     .plb_get_char = NULL,
     .is_directory = NULL,
     .is_file = NULL
 };
 void fat_lookup(ipc_callid_t rid, ipc_call_t *request)
+{
     libfs_lookup(&fat_libfs_ops, fat_reg.fs_handle, rid, request);
+}
 /**
  * @}
  */

Subversion Repositories HelenOS

(root)/trunk/uspace/srv/fs/fat/fat_ops.c @ 4680 – Rev 2798 → 2822