fix bug for indirect datablock r/w, add . and .. to every directory

include/files.h

@@ -5,12 +5,14 @@ class FilesOperation {
     RawDisk& disk;
     INodeOperation inop;
     u_int64_t root_inode;
+    INode* new_inode(u_int64_t inode_number, u_int64_t permissions);
+    void create_dot_dotdot(INode*, u_int64_t);
     public:
     FilesOperation(RawDisk&);
     int read_datablock(const INode& inode, u_int64_t index, char* buffer);
-    int write_datablock(INode& inode, u_int64_t index, char* buffer);
+    int write_datablock(INode& inode, u_int64_t index, const char* buffer);
-    INode* new_inode(u_int64_t inode_number, u_int64_t permissions);
     void initialize_rootinode();
+    void printDirectory(u_int64_t);
     u_int64_t create_new_inode(u_int64_t parent_inode_number, const char* name, mode_t mode);
     u_int64_t namei(const char* path);
     u_int64_t fischl_mkdir(const char*, mode_t);

include/rawdisk.h

@@ -64,7 +64,7 @@ public:
     }
 
     // Write a specified number of bytes at a given byte offset
-    int rawdisk_write(u_int64_t offset, char *buffer, size_t length) {
+    int rawdisk_write(u_int64_t offset, const char *buffer, size_t length) {
         if (lseek(fd, offset, SEEK_SET) == (u_int64_t)-1) {
             perror("Error seeking to offset");
             return -1;

lib/files.cpp

@@ -85,7 +85,7 @@ int FilesOperation::read_datablock(const INode& inode, u_int64_t index, char* bu
     return disk.rawdisk_read(read_offset, buffer, IO_BLOCK_SIZE);
 }
 
-int FilesOperation::write_datablock(INode& inode, u_int64_t index, char* buffer) {
+int FilesOperation::write_datablock(INode& inode, u_int64_t index, const char* buffer) {
     while (index >= inode.size) {
         u_int64_t ret = inode.datablock_allocate(disk);
         inode.size += 1;
@@ -94,7 +94,7 @@ int FilesOperation::write_datablock(INode& inode, u_int64_t index, char* buffer)
     if (write_offset == (u_int64_t)(-1)) {
         return -1;
     }
-    return disk.rawdisk_read(write_offset, buffer, IO_BLOCK_SIZE);
+    return disk.rawdisk_write(write_offset, buffer, IO_BLOCK_SIZE);
 }
 
 INode* FilesOperation::new_inode(u_int64_t inode_number, u_int64_t permissions) {
@@ -110,14 +110,45 @@ INode* FilesOperation::new_inode(u_int64_t inode_number, u_int64_t permissions)
     return inode;
 }
 
+void FilesOperation::create_dot_dotdot(INode* inode, u_int64_t parent_inode_number) {
+    if(inode->size != 0) {
+        printf("Error: create_dot_dotdot should only be called on new inode for directory\n");
+    }
+    char buffer[IO_BLOCK_SIZE] = {0};
+    DirectoryEntry dot;
+    dot.inode_number = inode->block_number;
+    strcpy(dot.file_name, ".");
+    dot.serialize(buffer);
+    DirectoryEntry dotdot;
+    dotdot.inode_number = parent_inode_number;
+    strcpy(dotdot.file_name, "..");
+    dotdot.serialize(buffer+64);
+    int ret = write_datablock(*inode, 0, buffer);
+    inode->inode_save(disk);
+}
+
 void FilesOperation::initialize_rootinode() {
     // this method must be called explicitly right after initializion
     root_inode = inop.inode_allocate(disk);
     printf("Info: root inode number: %llu\n", root_inode);
     INode *get_inode = new_inode(root_inode, S_IFDIR);
+    create_dot_dotdot(get_inode, root_inode);
     delete get_inode;
 }
 
+void FilesOperation::printDirectory(u_int64_t inode_number) {
+    INode inode;
+    inode.inode_construct(inode_number, disk);
+    char buffer[IO_BLOCK_SIZE] = {0};
+    read_datablock(inode, 0, buffer);
+    DirectoryEntry ent;
+    for(int i=0;i<=IO_BLOCK_SIZE-64;i+=64){
+        ent.deserialize(buffer+i);
+        printf("%d(%s)\t", i, ent.file_name);
+    }
+    printf("\n");
+}
+
 u_int64_t FilesOperation::create_new_inode(u_int64_t parent_inode_number, const char* name, mode_t mode) {
     // trys to create a file under parent directory
     if (strlen(name)>=56) {
@@ -156,6 +187,9 @@ u_int64_t FilesOperation::create_new_inode(u_int64_t parent_inode_number, const
 
     // initialize new file
     INode *get_inode = new_inode(new_inode_number, mode);
+    if ((get_inode->permissions & S_IFMT) == S_IFDIR) {
+        create_dot_dotdot(get_inode, parent_inode_number);
+    }
     delete get_inode;
     return new_inode_number;
 }

test/layer2_API.cpp

@@ -41,6 +41,8 @@ int main(int argc, char *argv[]) {
     inode.inode_construct(file4, *H);
     buffer[0] = '4';
     fsop.write_datablock(inode, 3, buffer);
+    buffer[0] = '5';
+    fsop.write_datablock(inode, 101, buffer);
     inode.inode_save(*H);
     // TODO: guard against overwriting directory datablocks
 
@@ -52,6 +54,12 @@ int main(int argc, char *argv[]) {
     u_int64_t file_baz = fsop.namei("/foo/bar/baz");
     printf("inode number for \"/foo/bar/baz\" is %llu\n", file_baz);
     assert(file_baz == file4);
+    u_int64_t file_foo = fsop.namei("/foo/bar/..");
+    printf("inode number for \"/foo/bar/..\" is %llu\n", file_foo);
+    assert(file_foo == file2);
+    u_int64_t file_bar = fsop.namei("/foo/bar/.");
+    printf("inode number for \"/foo/bar/.\" is %llu\n", file_bar);
+    assert(file_bar == file3);
 
     // read files (TODO: fischl_read)
     printf("=== Part 4: read from files ===\n");
@@ -63,4 +71,6 @@ int main(int argc, char *argv[]) {
     inode_read.inode_construct(file_baz, *H);
     fsop.read_datablock(inode_read, 3, read_buffer);
     assert(read_buffer[0] == '4');
+    fsop.read_datablock(inode_read, 101, read_buffer);
+    assert(read_buffer[0] == '5');
 }