freebsd-dev/contrib/less/cvt.c
Robert Watson 1ea316270f Currently, less(1) uses K&R prototypes, which both fails to provide useful
compiler-time type checking, and also causes problems for targets where
multiple incompatible calling conventions may be selected based on argument
types.  This change switches less(1) to ANSI prototypes.

While there, we also remove use of "register", and attempt to use "const" a
bit better now that the compiler can check argument types.

Reviewed by:	cem, emaste
MFC after:	3 weeks
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D10152
2017-03-31 21:29:43 +00:00

107 lines
2.4 KiB
C

/*
* Copyright (C) 1984-2015 Mark Nudelman
*
* You may distribute under the terms of either the GNU General Public
* License or the Less License, as specified in the README file.
*
* For more information, see the README file.
*/
/*
* Routines to convert text in various ways. Used by search.
*/
#include "less.h"
#include "charset.h"
extern int utf_mode;
/*
* Get the length of a buffer needed to convert a string.
*/
public int
cvt_length(int len, int ops)
{
if (utf_mode)
/*
* Just copying a string in UTF-8 mode can cause it to grow
* in length.
* Four output bytes for one input byte is the worst case.
*/
len *= 4;
return (len + 1);
}
/*
* Allocate a chpos array for use by cvt_text.
*/
public int *
cvt_alloc_chpos(int len)
{
int i;
int *chpos = (int *) ecalloc(sizeof(int), len);
/* Initialize all entries to an invalid position. */
for (i = 0; i < len; i++)
chpos[i] = -1;
return (chpos);
}
/*
* Convert text. Perform the transformations specified by ops.
* Returns converted text in odst. The original offset of each
* odst character (when it was in osrc) is returned in the chpos array.
*/
public void
cvt_text(char *odst, char *osrc, int *chpos, int *lenp, int ops)
{
char *dst;
char *edst = odst;
char *src;
char *src_end;
LWCHAR ch;
if (lenp != NULL)
src_end = osrc + *lenp;
else
src_end = osrc + strlen(osrc);
for (src = osrc, dst = odst; src < src_end; )
{
int src_pos = (int) (src - osrc);
int dst_pos = (int) (dst - odst);
ch = step_char((constant char **)&src, +1, src_end);
if ((ops & CVT_BS) && ch == '\b' && dst > odst)
{
/* Delete backspace and preceding char. */
do {
dst--;
} while (dst > odst &&
!IS_ASCII_OCTET(*dst) && !IS_UTF8_LEAD(*dst));
} else if ((ops & CVT_ANSI) && IS_CSI_START(ch))
{
/* Skip to end of ANSI escape sequence. */
src++; /* skip the CSI start char */
while (src < src_end)
if (!is_ansi_middle(*src++))
break;
} else
{
/* Just copy the char to the destination buffer. */
if ((ops & CVT_TO_LC) && IS_UPPER(ch))
ch = TO_LOWER(ch);
put_wchar(&dst, ch);
/* Record the original position of the char. */
if (chpos != NULL)
chpos[dst_pos] = src_pos;
}
if (dst > edst)
edst = dst;
}
if ((ops & CVT_CRLF) && edst > odst && edst[-1] == '\r')
edst--;
*edst = '\0';
if (lenp != NULL)
*lenp = (int) (edst - odst);
/* FIXME: why was this here? if (chpos != NULL) chpos[dst - odst] = src - osrc; */
}