rev.c revision 3f54fd611f536639ec30dd53c48e5ec1897cc7d9
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1992-2012 AT&T Intellectual Property *
* and is licensed under the *
* Eclipse Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.eclipse.org/org/documents/epl-v10.html *
* (with md5 checksum b35adb5213ca9657e911e9befb180842) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* Glenn Fowler <gsf@research.att.com> *
* David Korn <dgk@research.att.com> *
* *
***********************************************************************/
#pragma prototyped
/*
* rev [-l] [file ...]
*
* reverse the characters or lines of one or more files
*
* David Korn
* AT&T Laboratories
* dgk@research.att.com
*
*/
static const char usage[] =
"[-?\n@(#)$Id: rev (AT&T Research) 2007-11-29 $\n]"
USAGE_LICENSE
"[+NAME?rev - reverse the characters or lines of one or more files]"
"[+DESCRIPTION?\brev\b copies one or more files to standard output "
"reversing the order of characters on every line of the file "
"or reversing the order of lines of the file if \b-l\b is specified.]"
"[+?If no \afile\a is given, or if the \afile\a is \b-\b, \brev\b "
"copies from standard input starting at the current offset.]"
"[l:line?Reverse the lines of the file.]"
"\n"
"\n[file ...]\n"
"\n"
"[+EXIT STATUS?]{"
"[+0?All files copied successfully.]"
"[+>0?One or more files did not copy.]"
"}"
"[+SEE ALSO?\bcat\b(1), \btail\b(1)]"
;
#include <cmd.h>
#include <rev.h>
/*
* reverse the characters within a line
*/
static int rev_char(Sfio_t *in, Sfio_t *out)
{
register int c;
register char *ep, *bp, *cp;
register wchar_t *wp, *xp;
register size_t n;
register size_t w;
if (mbwide())
{
wp = 0;
w = 0;
while(cp = bp = sfgetr(in,'\n',0))
{
ep = bp + (n=sfvalue(in)) - 1;
if (n > w)
{
w = roundof(n + 1, 1024);
if (!(wp = newof(wp, wchar_t, w, 0)))
{
error(ERROR_SYSTEM|2, "out of space");
return 0;
}
}
xp = wp;
while (cp < ep)
*xp++ = mbchar(cp);
cp = bp;
while (xp > wp)
cp += mbconv(cp, *--xp);
*cp++ = '\n';
if (sfwrite(out, bp, cp - bp) < 0)
{
if (wp)
free(wp);
return -1;
}
}
if (wp)
free(wp);
}
else
while(cp = bp = sfgetr(in,'\n',0))
{
ep = bp + (n=sfvalue(in)) -1;
while(ep > bp)
{
c = *--ep;
*ep = *bp;
*bp++ = c;
}
if(sfwrite(out,cp,n)<0)
return(-1);
}
return(0);
}
int
b_rev(int argc, register char** argv, Shbltin_t* context)
{
register Sfio_t *fp;
register char *cp;
register int n, line=0;
NOT_USED(argc);
cmdinit(argc, argv, context, ERROR_CATALOG, 0);
for (;;)
{
switch (optget(argv, usage))
{
case 'l':
line=1;
continue;
case ':':
error(2, "%s", opt_info.arg);
break;
case '?':
error(ERROR_usage(2), "%s", opt_info.arg);
break;
}
break;
}
argv += opt_info.index;
if(error_info.errors)
error(ERROR_usage(2),"%s",optusage((char*)0));
n=0;
if(cp = *argv)
argv++;
do
{
if(!cp || streq(cp,"-"))
fp = sfstdin;
else if(!(fp = sfopen((Sfio_t*)0,cp,"r")))
{
error(ERROR_system(0),"%s: cannot open",cp);
n=1;
continue;
}
if(line)
line = rev_line(fp,sfstdout,sftell(fp));
else
line = rev_char(fp,sfstdout);
if(fp!=sfstdin)
sfclose(fp);
if(line < 0)
error(ERROR_system(1),"write failed");
}
while(cp= *argv++);
return(n);
}