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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/um/drivers/slip_common.h | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/um/drivers/slip_common.h')
-rw-r--r-- | kernel/arch/um/drivers/slip_common.h | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/kernel/arch/um/drivers/slip_common.h b/kernel/arch/um/drivers/slip_common.h new file mode 100644 index 000000000..d574e0a9d --- /dev/null +++ b/kernel/arch/um/drivers/slip_common.h @@ -0,0 +1,105 @@ +#ifndef __UM_SLIP_COMMON_H +#define __UM_SLIP_COMMON_H + +#define BUF_SIZE 1500 + /* two bytes each for a (pathological) max packet of escaped chars + * + * terminating END char + initial END char */ +#define ENC_BUF_SIZE (2 * BUF_SIZE + 2) + +/* SLIP protocol characters. */ +#define SLIP_END 0300 /* indicates end of frame */ +#define SLIP_ESC 0333 /* indicates byte stuffing */ +#define SLIP_ESC_END 0334 /* ESC ESC_END means END 'data' */ +#define SLIP_ESC_ESC 0335 /* ESC ESC_ESC means ESC 'data' */ + +static inline int slip_unesc(unsigned char c, unsigned char *buf, int *pos, + int *esc) +{ + int ret; + + switch(c){ + case SLIP_END: + *esc = 0; + ret=*pos; + *pos=0; + return(ret); + case SLIP_ESC: + *esc = 1; + return(0); + case SLIP_ESC_ESC: + if(*esc){ + *esc = 0; + c = SLIP_ESC; + } + break; + case SLIP_ESC_END: + if(*esc){ + *esc = 0; + c = SLIP_END; + } + break; + } + buf[(*pos)++] = c; + return(0); +} + +static inline int slip_esc(unsigned char *s, unsigned char *d, int len) +{ + unsigned char *ptr = d; + unsigned char c; + + /* + * Send an initial END character to flush out any + * data that may have accumulated in the receiver + * due to line noise. + */ + + *ptr++ = SLIP_END; + + /* + * For each byte in the packet, send the appropriate + * character sequence, according to the SLIP protocol. + */ + + while (len-- > 0) { + switch(c = *s++) { + case SLIP_END: + *ptr++ = SLIP_ESC; + *ptr++ = SLIP_ESC_END; + break; + case SLIP_ESC: + *ptr++ = SLIP_ESC; + *ptr++ = SLIP_ESC_ESC; + break; + default: + *ptr++ = c; + break; + } + } + *ptr++ = SLIP_END; + return (ptr - d); +} + +struct slip_proto { + unsigned char ibuf[ENC_BUF_SIZE]; + unsigned char obuf[ENC_BUF_SIZE]; + int more; /* more data: do not read fd until ibuf has been drained */ + int pos; + int esc; +}; + +static inline void slip_proto_init(struct slip_proto * slip) +{ + memset(slip->ibuf, 0, sizeof(slip->ibuf)); + memset(slip->obuf, 0, sizeof(slip->obuf)); + slip->more = 0; + slip->pos = 0; + slip->esc = 0; +} + +extern int slip_proto_read(int fd, void *buf, int len, + struct slip_proto *slip); +extern int slip_proto_write(int fd, void *buf, int len, + struct slip_proto *slip); + +#endif |