File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/um/drivers/slip_common.c b/arch/um/drivers/slip_common.c
new file mode 100644
index 0000000..f597fa7
--- /dev/null
+++ b/arch/um/drivers/slip_common.c
@@ -0,0 +1,54 @@
+#include <string.h>
+#include "slip_common.h"
+#include <net_user.h>
+
+int slip_proto_read(int fd, void *buf, int len, struct slip_proto *slip)
+{
+ int i, n, size, start;
+
+ if(slip->more > 0){
+ i = 0;
+ while(i < slip->more){
+ size = slip_unesc(slip->ibuf[i++], slip->ibuf,
+ &slip->pos, &slip->esc);
+ if(size){
+ memcpy(buf, slip->ibuf, size);
+ memmove(slip->ibuf, &slip->ibuf[i],
+ slip->more - i);
+ slip->more = slip->more - i;
+ return size;
+ }
+ }
+ slip->more = 0;
+ }
+
+ n = net_read(fd, &slip->ibuf[slip->pos],
+ sizeof(slip->ibuf) - slip->pos);
+ if(n <= 0)
+ return n;
+
+ start = slip->pos;
+ for(i = 0; i < n; i++){
+ size = slip_unesc(slip->ibuf[start + i], slip->ibuf,&slip->pos,
+ &slip->esc);
+ if(size){
+ memcpy(buf, slip->ibuf, size);
+ memmove(slip->ibuf, &slip->ibuf[start+i+1],
+ n - (i + 1));
+ slip->more = n - (i + 1);
+ return size;
+ }
+ }
+ return 0;
+}
+
+int slip_proto_write(int fd, void *buf, int len, struct slip_proto *slip)
+{
+ int actual, n;
+
+ actual = slip_esc(buf, slip->obuf, len);
+ n = net_write(fd, slip->obuf, actual);
+ if(n < 0)
+ return n;
+ else return len;
+}