[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit
Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/app/busybox/src/libbb/read.c b/ap/app/busybox/src/libbb/read.c
new file mode 100644
index 0000000..5906bc2
--- /dev/null
+++ b/ap/app/busybox/src/libbb/read.c
@@ -0,0 +1,72 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+#include "libbb.h"
+
+ssize_t FAST_FUNC safe_read(int fd, void *buf, size_t count)
+{
+ ssize_t n;
+
+ do {
+ n = read(fd, buf, count);
+ } while (n < 0 && errno == EINTR);
+
+ return n;
+}
+
+/*
+ * Read all of the supplied buffer from a file.
+ * This does multiple reads as necessary.
+ * Returns the amount read, or -1 on an error.
+ * A short read is returned on an end of file.
+ */
+ssize_t FAST_FUNC full_read(int fd, void *buf, size_t len)
+{
+ ssize_t cc;
+ ssize_t total;
+
+ total = 0;
+
+ while (len) {
+ cc = safe_read(fd, buf, len);
+
+ if (cc < 0) {
+ if (total) {
+ /* we already have some! */
+ /* user can do another read to know the error code */
+ return total;
+ }
+ return cc; /* read() returns -1 on failure. */
+ }
+ if (cc == 0)
+ break;
+ buf = ((char *)buf) + cc;
+ total += cc;
+ len -= cc;
+ }
+
+ return total;
+}
+
+ssize_t FAST_FUNC read_close(int fd, void *buf, size_t size)
+{
+ /*int e;*/
+ size = full_read(fd, buf, size);
+ /*e = errno;*/
+ close(fd);
+ /*errno = e;*/
+ return size;
+}
+
+ssize_t FAST_FUNC open_read_close(const char *filename, void *buf, size_t size)
+{
+ int fd = open(filename, O_RDONLY);
+ if (fd < 0)
+ return fd;
+ return read_close(fd, buf, size);
+}