1 files changed, 90 insertions, 0 deletions
diff --git a/busybox/libbb/copyfd.c b/busybox/libbb/copyfd.c
new file mode 100644
index 0000000..bf0a390
--- /dev/null
+++ b/busybox/libbb/copyfd.c
@@ -0,0 +1,90 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "busybox.h"
+
+
+#if BUFSIZ < 4096
+#undef BUFSIZ
+#define BUFSIZ 4096
+#endif
+
+
+/* If size is 0 copy until EOF */
+static size_t bb_full_fd_action(int src_fd, int dst_fd, const size_t size)
+{
+	size_t read_total = 0;
+	RESERVE_CONFIG_BUFFER(buffer,BUFSIZ);
+
+	while ((size == 0) || (read_total < size)) {
+		size_t read_try;
+		ssize_t read_actual;
+
+ 		if ((size == 0) || (size - read_total > BUFSIZ)) {
+			read_try = BUFSIZ;
+		} else {
+			read_try = size - read_total;
+		}
+
+		read_actual = safe_read(src_fd, buffer, read_try);
+		if (read_actual > 0) {
+			if ((dst_fd >= 0) && (bb_full_write(dst_fd, buffer, (size_t) read_actual) != read_actual)) {
+				bb_perror_msg(bb_msg_write_error);	/* match Read error below */
+				break;
+			}
+		}
+		else if (read_actual == 0) {
+			if (size) {
+				bb_error_msg("Unable to read all data");
+			}
+			break;
+		} else {
+			/* read_actual < 0 */
+			bb_perror_msg("Read error");
+			break;
+		}
+
+		read_total += read_actual;
+	}
+
+	RELEASE_CONFIG_BUFFER(buffer);
+
+	return(read_total);
+}
+
+
+extern int bb_copyfd_size(int fd1, int fd2, const off_t size)
+{
+	if (size) {
+		return(bb_full_fd_action(fd1, fd2, size));
+	}
+	return(0);
+}
+
+extern int bb_copyfd_eof(int fd1, int fd2)
+{
+	return(bb_full_fd_action(fd1, fd2, 0));
+}