ext2fs.c

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		buf += blocksize - skipfirst;
	}
	return (len);
}


static int ext2fs_iterate_dir (ext2fs_node_t dir, char *name, ext2fs_node_t * fnode, int *ftype)
{
	unsigned int fpos = 0;
	int status;
	struct ext2fs_node *diro = (struct ext2fs_node *) dir;

#ifdef DEBUG
	if (name != NULL)
		printf ("Iterate dir %s\n", name);
#endif /* of DEBUG */
	if (!diro->inode_read) {
		status = ext2fs_read_inode (diro->data, diro->ino,
					    &diro->inode);
		if (status == 0) {
			return (0);
		}
	}
	/* Search the file.  */
	while (fpos < __le32_to_cpu (diro->inode.size)) {
		struct ext2_dirent dirent;

		status = ext2fs_read_file (diro, fpos,
					   sizeof (struct ext2_dirent),
					   (char *) &dirent);
		if (status < 1) {
			return (0);
		}
		if (dirent.namelen != 0) {
			char filename[dirent.namelen + 1];
			ext2fs_node_t fdiro;
			int type = FILETYPE_UNKNOWN;

			status = ext2fs_read_file (diro,
						   fpos + sizeof (struct ext2_dirent),
						   dirent.namelen, filename);
			if (status < 1) {
				return (0);
			}
			fdiro = malloc (sizeof (struct ext2fs_node));
			if (!fdiro) {
				return (0);
			}

			fdiro->data = diro->data;
			fdiro->ino = __le32_to_cpu (dirent.inode);

			filename[dirent.namelen] = '\0';

			if (dirent.filetype != FILETYPE_UNKNOWN) {
				fdiro->inode_read = 0;

				if (dirent.filetype == FILETYPE_DIRECTORY) {
					type = FILETYPE_DIRECTORY;
				} else if (dirent.filetype ==
					   FILETYPE_SYMLINK) {
					type = FILETYPE_SYMLINK;
				} else if (dirent.filetype == FILETYPE_REG) {
					type = FILETYPE_REG;
				}
			} else {
				/* The filetype can not be read from the dirent, get it from inode */

				status = ext2fs_read_inode (diro->data,
							    __le32_to_cpu(dirent.inode),
							    &fdiro->inode);
				if (status == 0) {
					free (fdiro);
					return (0);
				}
				fdiro->inode_read = 1;

				if ((__le16_to_cpu (fdiro->inode.mode) &
				     FILETYPE_INO_MASK) ==
				    FILETYPE_INO_DIRECTORY) {
					type = FILETYPE_DIRECTORY;
				} else if ((__le16_to_cpu (fdiro->inode.mode)
					    & FILETYPE_INO_MASK) ==
					   FILETYPE_INO_SYMLINK) {
					type = FILETYPE_SYMLINK;
				} else if ((__le16_to_cpu (fdiro->inode.mode)
					    & FILETYPE_INO_MASK) ==
					   FILETYPE_INO_REG) {
					type = FILETYPE_REG;
				}
			}
#ifdef DEBUG
			printf ("iterate >%s<\n", filename);
#endif /* of DEBUG */
			if ((name != NULL) && (fnode != NULL)
			    && (ftype != NULL)) {
				if (strcmp (filename, name) == 0) {
					*ftype = type;
					*fnode = fdiro;
					return (1);
				}
			} else {
				if (fdiro->inode_read == 0) {
					status = ext2fs_read_inode (diro->data,
							    __le32_to_cpu (dirent.inode),
							    &fdiro->inode);
					if (status == 0) {
						free (fdiro);
						return (0);
					}
					fdiro->inode_read = 1;
				}
				switch (type) {
				case FILETYPE_DIRECTORY:
					printf ("<DIR> ");
					break;
				case FILETYPE_SYMLINK:
					printf ("<SYM> ");
					break;
				case FILETYPE_REG:
					printf ("      ");
					break;
				default:
					printf ("< ? > ");
					break;
				}
				printf ("%10d %s\n",
					__le32_to_cpu (fdiro->inode.size),
					filename);
			}
			free (fdiro);
		}
		fpos += __le16_to_cpu (dirent.direntlen);
	}
	return (0);
}


static char *ext2fs_read_symlink (ext2fs_node_t node) {
	char *symlink;
	struct ext2fs_node *diro = node;
	int status;

	if (!diro->inode_read) {
		status = ext2fs_read_inode (diro->data, diro->ino,
					    &diro->inode);
		if (status == 0) {
			return (0);
		}
	}
	symlink = malloc (__le32_to_cpu (diro->inode.size) + 1);
	if (!symlink) {
		return (0);
	}
	/* If the filesize of the symlink is bigger than
	   60 the symlink is stored in a separate block,
	   otherwise it is stored in the inode.  */
	if (__le32_to_cpu (diro->inode.size) <= 60) {
		strncpy (symlink, diro->inode.b.symlink,
			 __le32_to_cpu (diro->inode.size));
	} else {
		status = ext2fs_read_file (diro, 0,
					   __le32_to_cpu (diro->inode.size),
					   symlink);
		if (status == 0) {
			free (symlink);
			return (0);
		}
	}
	symlink[__le32_to_cpu (diro->inode.size)] = '\0';
	return (symlink);
}


int ext2fs_find_file1
	(const char *currpath,
	 ext2fs_node_t currroot, ext2fs_node_t * currfound, int *foundtype) {
	char fpath[strlen (currpath) + 1];
	char *name = fpath;
	char *next;
	int status;
	int type = FILETYPE_DIRECTORY;
	ext2fs_node_t currnode = currroot;
	ext2fs_node_t oldnode = currroot;

	strncpy (fpath, currpath, strlen (currpath) + 1);

	/* Remove all leading slashes.  */
	while (*name == '/') {
		name++;
	}
	if (!*name) {
		*currfound = currnode;
		return (1);
	}

	for (;;) {
		int found;

		/* Extract the actual part from the pathname.  */
		next = strchr (name, '/');
		if (next) {
			/* Remove all leading slashes.  */
			while (*next == '/') {
				*(next++) = '\0';
			}
		}

		/* At this point it is expected that the current node is a directory, check if this is true.  */
		if (type != FILETYPE_DIRECTORY) {
			ext2fs_free_node (currnode, currroot);
			return (0);
		}

		oldnode = currnode;

		/* Iterate over the directory.  */
		found = ext2fs_iterate_dir (currnode, name, &currnode, &type);
		if (found == 0) {
			return (0);
		}
		if (found == -1) {
			break;
		}

		/* Read in the symlink and follow it.  */
		if (type == FILETYPE_SYMLINK) {
			char *symlink;

			/* Test if the symlink does not loop.  */
			if (++symlinknest == 8) {
				ext2fs_free_node (currnode, currroot);
				ext2fs_free_node (oldnode, currroot);
				return (0);
			}

			symlink = ext2fs_read_symlink (currnode);
			ext2fs_free_node (currnode, currroot);

			if (!symlink) {
				ext2fs_free_node (oldnode, currroot);
				return (0);
			}
#ifdef DEBUG
			printf ("Got symlink >%s<\n", symlink);
#endif /* of DEBUG */
			/* The symlink is an absolute path, go back to the root inode.  */
			if (symlink[0] == '/') {
				ext2fs_free_node (oldnode, currroot);
				oldnode = &ext2fs_root->diropen;
			}

			/* Lookup the node the symlink points to.  */
			status = ext2fs_find_file1 (symlink, oldnode,
						    &currnode, &type);

			free (symlink);

			if (status == 0) {
				ext2fs_free_node (oldnode, currroot);
				return (0);
			}
		}

		ext2fs_free_node (oldnode, currroot);

		/* Found the node!  */
		if (!next || *next == '\0') {
			*currfound = currnode;
			*foundtype = type;
			return (1);
		}
		name = next;
	}
	return (-1);
}


int ext2fs_find_file
	(const char *path,
	 ext2fs_node_t rootnode, ext2fs_node_t * foundnode, int expecttype) {
	int status;
	int foundtype = FILETYPE_DIRECTORY;


	symlinknest = 0;
	if (!path || path[0] != '/') {
		return (0);
	}

	status = ext2fs_find_file1 (path, rootnode, foundnode, &foundtype);
	if (status == 0) {
		return (0);
	}
	/* Check if the node that was found was of the expected type.  */
	if ((expecttype == FILETYPE_REG) && (foundtype != expecttype)) {
		return (0);
	} else if ((expecttype == FILETYPE_DIRECTORY)
		   && (foundtype != expecttype)) {
		return (0);
	}
	return (1);
}


int ext2fs_ls (char *dirname) {
	ext2fs_node_t dirnode;
	int status;

	if (ext2fs_root == NULL) {
		return (0);
	}

	status = ext2fs_find_file (dirname, &ext2fs_root->diropen, &dirnode,
				   FILETYPE_DIRECTORY);
	if (status != 1) {
		printf ("** Can not find directory. **\n");
		return (1);
	}
	ext2fs_iterate_dir (dirnode, NULL, NULL, NULL);
	ext2fs_free_node (dirnode, &ext2fs_root->diropen);
	return (0);
}


int ext2fs_open (char *filename) {
	ext2fs_node_t fdiro = NULL;
	int status;
	int len;

	if (ext2fs_root == NULL) {
		return (0);
	}
	ext2fs_file = NULL;
	status = ext2fs_find_file (filename, &ext2fs_root->diropen, &fdiro,
				   FILETYPE_REG);
	if (status == 0) {
		goto fail;
	}
	if (!fdiro->inode_read) {
		status = ext2fs_read_inode (fdiro->data, fdiro->ino,
					    &fdiro->inode);
		if (status == 0) {
			goto fail;
		}
	}
	len = __le32_to_cpu (fdiro->inode.size);
	ext2fs_file = fdiro;
	return (len);

      fail:
	ext2fs_free_node (fdiro, &ext2fs_root->diropen);
	return (0);
}


int ext2fs_close (void
	) {
	if ((ext2fs_file != NULL) && (ext2fs_root != NULL)) {
		ext2fs_free_node (ext2fs_file, &ext2fs_root->diropen);
		ext2fs_file = NULL;
	}
	if (ext2fs_root != NULL) {
		free (ext2fs_root);
		ext2fs_root = NULL;
	}
	if (indir1_block != NULL) {
		free (indir1_block);
		indir1_block = NULL;
		indir1_size = 0;
		indir1_blkno = -1;
	}
	if (indir2_block != NULL) {
		free (indir2_block);
		indir2_block = NULL;
		indir2_size = 0;
		indir2_blkno = -1;
	}
	return (0);
}


int ext2fs_read (char *buf, unsigned len) {
	int status;

	if (ext2fs_root == NULL) {
		return (0);
	}

	if (ext2fs_file == NULL) {
		return (0);
	}

	status = ext2fs_read_file (ext2fs_file, 0, len, buf);
	return (status);
}


int ext2fs_mount (unsigned part_length) {
	struct ext2_data *data;
	int status;

	data = malloc (sizeof (struct ext2_data));
	if (!data) {
		return (0);
	}
	/* Read the superblock.  */
	status = ext2fs_devread (1 * 2, 0, sizeof (struct ext2_sblock),
				 (char *) &data->sblock);
	if (status == 0) {
		goto fail;
	}
	/* Make sure this is an ext2 filesystem.  */
	if (__le16_to_cpu (data->sblock.magic) != EXT2_MAGIC) {
		goto fail;
	}
	data->diropen.data = data;
	data->diropen.ino = 2;
	data->diropen.inode_read = 1;
	data->inode = &data->diropen.inode;

	status = ext2fs_read_inode (data, 2, data->inode);
	if (status == 0) {
		goto fail;
	}

	ext2fs_root = data;

	return (1);

fail:
	printf ("Failed to mount ext2 filesystem...\n");
	free (data);
	ext2fs_root = NULL;
	return (0);
}

#endif /* CFG_CMD_EXT2FS */