Add tcgetblob support to extfs.

ext/device.cpp

@@ -40,10 +40,11 @@ void* Device__SyncThread(void* ctx)
 	return NULL;
 }
 
-Device::Device(int fd, uint32_t block_size, bool write)
+Device::Device(int fd, const char* path, uint32_t block_size, bool write)
 {
 	this->write = write;
 	this->fd = fd;
+	this->path = path;
 	this->block_size = block_size;
 	struct stat st;
 	fstat(fd, &st);

ext/device.h

@@ -30,7 +30,7 @@ const size_t DEVICE_HASH_LENGTH = 1 << 16;
 class Device
 {
 public:
-	Device(int fd, uint32_t block_size, bool write);
+	Device(int fd, const char* path, uint32_t block_size, bool write);
 	~Device();
 
 public:
@@ -43,6 +43,7 @@ public:
 	Block* dirty_block;
 	Block* hash_blocks[DEVICE_HASH_LENGTH];
 	off_t device_size;
+	const char* path;
 	uint32_t block_size;
 	int fd;
 	bool write;

ext/extfs.cpp

@@ -371,8 +371,8 @@ int main(int argc, char* argv[])
 
 	uint32_t block_size = 1024U << sb.s_log_block_size;
 
-	Device* dev = new Device(fd, block_size, write);
+	Device* dev = new Device(fd, device_path, block_size, write);
-	Filesystem* fs = new Filesystem(dev);
+	Filesystem* fs = new Filesystem(dev, mount_path);
 
 	fs->block_groups = new BlockGroup*[fs->num_groups];
 	for ( size_t i = 0; i < fs->num_groups; i++ )

ext/filesystem.cpp

@@ -38,7 +38,7 @@
 #include "inode.h"
 #include "util.h"
 
-Filesystem::Filesystem(Device* device)
+Filesystem::Filesystem(Device* device, const char* mount_path)
 {
 	uint64_t sb_offset = 1024;
 	uint32_t sb_block_id = sb_offset / device->block_size;
@@ -47,6 +47,7 @@ Filesystem::Filesystem(Device* device)
 		(sb_block->block_data + sb_offset % device->block_size);
 	this->device = device;
 	block_groups = NULL;
+	this->mount_path = mount_path;
 	block_size = device->block_size;
 	mru_inode = NULL;
 	lru_inode = NULL;

ext/filesystem.h

@@ -32,7 +32,7 @@ const size_t INODE_HASH_LENGTH = 1 << 16;
 class Filesystem
 {
 public:
-	Filesystem(Device* device);
+	Filesystem(Device* device, const char* mount_path);
 	~Filesystem();
 
 public:
@@ -40,6 +40,7 @@ public:
 	Block* sb_block;
 	Device* device;
 	BlockGroup** block_groups;
+	const char* mount_path;
 	uint32_t block_size;
 	uint32_t inode_size;
 	uint32_t num_blocks;

ext/fsmarshall.cpp

@@ -150,6 +150,14 @@ bool RespondReadDir(int chl, struct kernel_dirent* dirent)
 	       RespondData(chl, dirent->d_name, dirent->d_namlen);
 }
 
+bool RespondTCGetBlob(int chl, const void* data, size_t data_size)
+{
+	struct fsm_resp_tcgetblob body;
+	body.count = data_size;
+	return RespondMessage(chl, FSM_RESP_TCGETBLOB, &body, sizeof(body)) &&
+	       RespondData(chl, data, data_size);
+}
+
 void HandleRefer(int chl, struct fsm_req_refer* msg, Filesystem* fs)
 {
 	(void) chl;
@@ -577,6 +585,35 @@ void HandleRename(int chl, struct fsm_req_rename* msg, Filesystem* fs)
 	free(path);
 }
 
+void HandleTCGetBlob(int chl, struct fsm_req_tcgetblob* msg, Filesystem* fs)
+{
+	if ( fs->num_inodes <= msg->ino )
+		return (void) RespondError(chl, EBADF);
+
+	char* nameraw = (char*) &(msg[1]);
+	char* name = (char*) malloc(msg->namelen + 1);
+	if ( !name )
+		return (void) RespondError(chl, errno);
+	memcpy(name, nameraw, msg->namelen);
+	name[msg->namelen] = '\0';
+
+	static const char index[] = "device-path\0filesystem-type\0filesystem-uuid\0mount-path\0";
+	if ( !strcmp(name, "") )
+		RespondTCGetBlob(chl, index, sizeof(index) - 1);
+	else if ( !strcmp(name, "device-path") )
+		RespondTCGetBlob(chl, fs->device->path, strlen(fs->device->path));
+	else if ( !strcmp(name, "filesystem-type") )
+		RespondTCGetBlob(chl, "ext2", strlen("ext2"));
+	else if ( !strcmp(name, "filesystem-uuid") )
+		RespondTCGetBlob(chl, fs->sb->s_uuid, sizeof(fs->sb->s_uuid));
+	else if ( !strcmp(name, "mount-path") )
+		RespondTCGetBlob(chl, fs->mount_path, strlen(fs->mount_path));
+	else
+		RespondError(chl, ENOENT);
+
+	free(name);
+}
+
 void HandleIncomingMessage(int chl, struct fsm_msg_header* hdr, Filesystem* fs)
 {
 	typedef void (*handler_t)(int, void*, Filesystem*);
@@ -602,6 +639,7 @@ void HandleIncomingMessage(int chl, struct fsm_msg_header* hdr, Filesystem* fs)
 	handlers[FSM_REQ_RENAME] = (handler_t) HandleRename;
 	handlers[FSM_REQ_REFER] = (handler_t) HandleRefer;
 	handlers[FSM_REQ_UNREF] = (handler_t) HandleUnref;
+	handlers[FSM_REQ_TCGETBLOB] = (handler_t) HandleTCGetBlob;
 	if ( FSM_MSG_NUM <= hdr->msgtype || !handlers[hdr->msgtype] )
 	{
 		fprintf(stderr, "extfs: message type %zu not supported!\n", hdr->msgtype);
@@ -682,7 +720,7 @@ int fsmarshall_main(const char* argv0,
 		size_t amount;
 		if ( (amount = readall(channel, &hdr, sizeof(hdr))) != sizeof(hdr) )
 		{
-			error(0, errno, "incomplete header: got %zi of %zu bytes", amount, sizeof(hdr));
+			//error(0, errno, "incomplete header: got %zi of %zu bytes", amount, sizeof(hdr));
 			errno = 0;
 			continue;
 		}