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Release 4.14 arch/um/drivers/slip_common.h

Directory: arch/um/drivers
/* SPDX-License-Identifier: GPL-2.0 */
#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); }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Dike125100.00%2100.00%
Total125100.00%2100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Dike111100.00%1100.00%
Total111100.00%1100.00%

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; }

Contributors

PersonTokensPropCommitsCommitProp
Paolo 'Blaisorblade' Giarrusso62100.00%1100.00%
Total62100.00%1100.00%

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

Overall Contributors

PersonTokensPropCommitsCommitProp
Jeff Dike34384.48%360.00%
Paolo 'Blaisorblade' Giarrusso6215.27%120.00%
Greg Kroah-Hartman10.25%120.00%
Total406100.00%5100.00%
Directory: arch/um/drivers
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