github.com/spotify/syslog-redirector-golang@v0.0.0-20140320174030-4859f03d829a/src/lib9/utf/utfrrune.c (about)

     1  /*
     2   * The authors of this software are Rob Pike and Ken Thompson.
     3   *              Copyright (c) 2002 by Lucent Technologies.
     4   * Permission to use, copy, modify, and distribute this software for any
     5   * purpose without fee is hereby granted, provided that this entire notice
     6   * is included in all copies of any software which is or includes a copy
     7   * or modification of this software and in all copies of the supporting
     8   * documentation for such software.
     9   * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
    10   * WARRANTY.  IN PARTICULAR, NEITHER THE AUTHORS NOR LUCENT TECHNOLOGIES MAKE ANY
    11   * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
    12   * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
    13   */
    14  #include <string.h>
    15  #include "utf.h"
    16  #include "utfdef.h"
    17  
    18  /* const - removed for go code */
    19  char*
    20  utfrrune(const char *s, Rune c)
    21  {
    22  	long c1;
    23  	Rune r;
    24  	const char *s1;
    25  
    26  	if(c < Runesync)		/* not part of utf sequence */
    27  		return strrchr(s, (char)c);
    28  
    29  	s1 = 0;
    30  	for(;;) {
    31  		c1 = *(uchar*)s;
    32  		if(c1 < Runeself) {	/* one byte rune */
    33  			if(c1 == 0)
    34  				return (char*)s1;
    35  			if(c1 == c)
    36  				s1 = s;
    37  			s++;
    38  			continue;
    39  		}
    40  		c1 = chartorune(&r, s);
    41  		if(r == c)
    42  			s1 = s;
    43  		s += c1;
    44  	}
    45  	return 0;
    46  }