Changeset 529edc66 in mainline

Timestamp:

2011-03-09T13:12:49Z (13 years ago)

Author:

Martin Sucha <sucha14@…>

Branches:

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

Children:

242b4bb

Parents:

df38657

Message:

Add support for reading files to ext2fs

File:

• uspace/srv/fs/ext2fs/ext2fs_ops.c (modified) (3 diffs)

uspace/srv/fs/ext2fs/ext2fs_ops.c

@@ -74 +74 @@
 static void ext2fs_read_directory(ipc_callid_t, ipc_callid_t, aoff64_t,
         size_t, ext2fs_instance_t *, ext2_inode_ref_t *);
+static void ext2fs_read_file(ipc_callid_t, ipc_callid_t, aoff64_t,
+        size_t, ext2fs_instance_t *, ext2_inode_ref_t *);
 
 /*
@@ -596 +598 @@
         if (ext2_inode_is_type(inst->filesystem->superblock, inode_ref->inode,
                     EXT2_INODE_MODE_FILE)) {
-                async_answer_0(callid, ENOTSUP);
-                async_answer_0(rid, ENOTSUP);
+                ext2fs_read_file(rid, callid, pos, size, inst, inode_ref);
         }
         else if (ext2_inode_is_type(inst->filesystem->superblock, inode_ref->inode,
@@ -700 +701 @@
 }
 
+void ext2fs_read_file(ipc_callid_t rid, ipc_callid_t callid, aoff64_t pos,
+        size_t size, ext2fs_instance_t *inst, ext2_inode_ref_t *inode_ref)
+{
+        int rc;
+        uint32_t block_size;
+        aoff64_t file_block;
+        uint64_t file_size;
+        uint32_t fs_block;
+        size_t offset_in_block;
+        size_t bytes;
+        block_t *block;
+        
+        file_size = ext2_inode_get_size(inst->filesystem->superblock,
+                inode_ref->inode);
+        
+        if (pos >= file_size) {
+                // TODO: is this OK? return EIO?
+                async_data_read_finalize(callid, NULL, 0);
+                async_answer_1(rid, EOK, 0);
+                return;
+        }
+        
+        // For now, we only read data from one block at a time
+        block_size = ext2_superblock_get_block_size(inst->filesystem->superblock);
+        file_block = pos / block_size;
+        offset_in_block = pos % block_size;
+        bytes = min(block_size - offset_in_block, size);
+        
+        rc = ext2_filesystem_get_inode_data_block_index(inst->filesystem,
+                inode_ref->inode, file_block, &fs_block);
+        if (rc != EOK) {
+                async_answer_0(callid, rc);
+                async_answer_0(rid, rc);
+                return;
+        }
+        
+        rc = block_get(&block, inst->devmap_handle, fs_block, BLOCK_FLAGS_NONE);
+        if (rc != EOK) {
+                async_answer_0(callid, rc);
+                async_answer_0(rid, rc);
+                return;
+        }
+        
+        async_data_read_finalize(callid, block->data, bytes);
+        
+        rc = block_put(block);
+        if (rc != EOK) {
+                async_answer_0(rid, rc);
+                return;
+        }
+                
+        async_answer_1(rid, EOK, bytes);
+}
+
 void ext2fs_write(ipc_callid_t rid, ipc_call_t *request)
 {