busybox/archival/libunarchive/data_extract_all.c

/* vi: set sw=4 ts=4: */
/*
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

#include "libbb.h"
#include "unarchive.h"

void data_extract_all(archive_handle_t *archive_handle)
{
	file_header_t *file_header = archive_handle->file_header;
	int dst_fd;
	int res;

	if (archive_handle->flags & ARCHIVE_CREATE_LEADING_DIRS) {
		char *name = xstrdup(file_header->name);
		bb_make_directory (dirname(name), -1, FILEUTILS_RECUR);
		free(name);
	}

	/* Check if the file already exists */
	if (archive_handle->flags & ARCHIVE_EXTRACT_UNCONDITIONAL) {
		/* Remove the existing entry if it exists */
		if (((file_header->mode & S_IFMT) != S_IFDIR) && (unlink(file_header->name) == -1) && (errno != ENOENT)) {
			bb_perror_msg_and_die("Couldnt remove old file");
		}
	}
	else if (archive_handle->flags & ARCHIVE_EXTRACT_NEWER) {
		/* Remove the existing entry if its older than the extracted entry */
		struct stat statbuf;
		if (lstat(file_header->name, &statbuf) == -1) {
			if (errno != ENOENT) {
				bb_perror_msg_and_die("Couldnt stat old file");
			}
		}
		else if (statbuf.st_mtime <= file_header->mtime) {
			if (!(archive_handle->flags & ARCHIVE_EXTRACT_QUIET)) {
				bb_error_msg("%s not created: newer or same age file exists", file_header->name);
			}
			data_skip(archive_handle);
			return;
		}
		else if ((unlink(file_header->name) == -1) && (errno != EISDIR)) {
			bb_perror_msg_and_die("Couldnt remove old file %s", file_header->name);
		}
	}

	/* Handle hard links separately
	 * We identified hard links as regular files of size 0 with a symlink */
	if (S_ISREG(file_header->mode) && (file_header->link_name) && (file_header->size == 0)) {
		/* hard link */
		res = link(file_header->link_name, file_header->name);
		if ((res == -1) && !(archive_handle->flags & ARCHIVE_EXTRACT_QUIET)) {
			bb_perror_msg("Couldnt create hard link");
		}
	} else {
		/* Create the filesystem entry */
		switch (file_header->mode & S_IFMT) {
			case S_IFREG: {
				/* Regular file */
				dst_fd = xopen3(file_header->name, O_WRONLY | O_CREAT | O_EXCL,
								file_header->mode);
				bb_copyfd_size(archive_handle->src_fd, dst_fd, file_header->size);
				close(dst_fd);
				break;
				}
			case S_IFDIR:
				res = mkdir(file_header->name, file_header->mode);
				if ((errno != EISDIR) && (res == -1) && !(archive_handle->flags & ARCHIVE_EXTRACT_QUIET)) {
					bb_perror_msg("extract_archive: %s", file_header->name);
				}
				break;
			case S_IFLNK:
				/* Symlink */
				res = symlink(file_header->link_name, file_header->name);
				if ((res == -1) && !(archive_handle->flags & ARCHIVE_EXTRACT_QUIET)) {
					bb_perror_msg("Cannot create symlink from %s to '%s'", file_header->name, file_header->link_name);
				}
				break;
			case S_IFSOCK:
			case S_IFBLK:
			case S_IFCHR:
			case S_IFIFO:
				res = mknod(file_header->name, file_header->mode, file_header->device);
				if ((res == -1) && !(archive_handle->flags & ARCHIVE_EXTRACT_QUIET)) {
					bb_perror_msg("Cannot create node %s", file_header->name);
				}
				break;
			default:
				bb_error_msg_and_die("Unrecognised file type");
		}
	}

	if (!(archive_handle->flags & ARCHIVE_NOPRESERVE_OWN)) {
		lchown(file_header->name, file_header->uid, file_header->gid);
	}

	if (archive_handle->flags & ARCHIVE_PRESERVE_DATE) {
		struct utimbuf t;
		t.actime = t.modtime = file_header->mtime;
		utime(file_header->name, &t);
	}
}