1 files changed, 44 insertions, 0 deletions
diff --git a/archival/libunarchive/open_transformer.c b/archival/libunarchive/open_transformer.c
new file mode 100644
index 000000000..456d3e986
--- /dev/null
+++ b/archival/libunarchive/open_transformer.c
@@ -0,0 +1,44 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ */
+
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "libbb.h"
+
+#include "unarchive.h"
+
+/* transformer(), more than meets the eye */
+int open_transformer(int src_fd,
+	USE_DESKTOP(long long) int (*transformer)(int src_fd, int dst_fd))
+{
+	int fd_pipe[2];
+	int pid;
+
+	if (pipe(fd_pipe) != 0) {
+		bb_perror_msg_and_die("can't create pipe");
+	}
+
+	pid = fork();
+	if (pid == -1) {
+		bb_perror_msg_and_die("fork failed");
+	}
+
+	if (pid == 0) {
+		/* child process */
+		close(fd_pipe[0]); /* We don't wan't to read from the parent */
+		// FIXME: error check?
+		transformer(src_fd, fd_pipe[1]);
+		close(fd_pipe[1]); /* Send EOF */
+		close(src_fd);
+		exit(0);
+		/* notreached */
+	}
+
+	/* parent process */
+	close(fd_pipe[1]); /* Don't want to write to the child */
+
+	return fd_pipe[0];
+}