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/*
* copy - test program for my getopt() re-implementation
*
* This program is in the public domain.
*/
#define COPYRIGHT \
"This program is in the public domain."
/* for isprint(), printf(), fopen(), perror(), getenv(), strcmp(), etc. */
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/* for my getopt() re-implementation */
#include "compat_getopt.h"
#undef VERSION
#define VERSION "0.3"
/* the default verbosity level is 0 (no verbose reporting) */
static unsigned verbose = 0;
/* print version and copyright information */
static void
version(char *progname)
{
printf("%s version %s\n"
"%s\n",
progname,
VERSION,
COPYRIGHT);
}
/* print a help summary */
static void
help(char *progname)
{
printf("Usage: %s [options] [FILE]...\n"
"Options:\n"
"-h or -help show this message and exit\n"
"-append append to the output file\n"
"-o FILE or\n"
"-output FILE send output to FILE (default is stdout)\n"
"-r or --rotate rotate letters 13 positions (rot13)\n"
"-rNUM or\n"
"--rotate=NUM rotate letters NUM positions\n"
"-truncate truncate the output file "
"(this is the default)\n"
"-v or -verbose increase the level of verbosity by 1"
"(the default is 0)\n"
"-vNUM or\n"
"-verbose=NUM set the level of verbosity to NUM\n"
"-V or -version print program version and exit\n"
"\n"
"This program reads the specified FILEs "
"(or stdin if none are given)\n"
"and writes their bytes to the specified output FILE "
"(or stdout if none is\n"
"given.) It can optionally rotate letters.\n",
progname);
}
/* print usage information to stderr */
static void
usage(char *progname)
{
fprintf(stderr,
"Summary: %s [-help] [-version] [options] [FILE]...\n",
progname);
}
/* input file handler -- returns nonzero or exit()s on failure */
static int
handle(char *progname,
FILE *infile, const char *infilename,
FILE *outfile, const char *outfilename,
int rotate)
{
int c;
unsigned long bytes_copied = 0;
if (verbose > 2)
{
fprintf(stderr,
"%s: copying from `%s' to `%s'\n",
progname,
infilename,
outfilename);
}
while ((c = getc(infile)) != EOF)
{
if (rotate && isalpha(c))
{
const char *letters = "abcdefghijklmnopqrstuvwxyz";
char *match;
if ((match = strchr(letters, tolower(c))))
{
char rc = letters[(match - letters + rotate) % 26];
if (isupper(c))
rc = toupper(rc);
c = rc;
}
}
if (putc(c, outfile) == EOF)
{
perror(outfilename);
exit(1);
}
bytes_copied ++;
}
if (! feof(infile))
{
perror(infilename);
return 1;
}
if (verbose > 2)
{
fprintf(stderr,
"%s: %lu bytes copied from `%s' to `%s'\n",
progname, bytes_copied, infilename, outfilename);
}
return 0;
}
/* argument parser and dispatcher */
int
main(int argc, char * argv[])
{
/* the program name */
char *progname = argv[0];
/* during argument parsing, opt contains the return value from getopt() */
int opt;
/* the output filename is initially 0 (a.k.a. stdout) */
const char *outfilename = 0;
/* the default return value is initially 0 (success) */
int retval = 0;
/* initially we truncate */
int append = 0;
/* initially we don't rotate letters */
int rotate = 0;
/* short options string */
const char *shortopts = "Vho:r::v::";
/* long options list */
struct option longopts[] =
{
/* name, has_arg, flag, val */ /* longind */
{ "append", no_argument, 0, 0 }, /* 0 */
{ "truncate", no_argument, 0, 0 }, /* 1 */
{ "version", no_argument, 0, 'V' }, /* 3 */
{ "help", no_argument, 0, 'h' }, /* 4 */
{ "output", required_argument, 0, 'o' }, /* 5 */
{ "rotate", optional_argument, 0, 'r' }, /* 6 */
{ "verbose", optional_argument, 0, 'v' }, /* 7 */
/* end-of-list marker */
{ 0, 0, 0, 0 }
};
/* long option list index */
int longind = 0;
/*
* print a warning when the POSIXLY_CORRECT environment variable will
* interfere with argument placement
*/
if (getenv("POSIXLY_CORRECT"))
{
fprintf(stderr,
"%s: "
"Warning: implicit argument reordering disallowed by "
"POSIXLY_CORRECT\n",
progname);
}
/* parse all options from the command line */
while ((opt =
getopt_long_only(argc, argv, shortopts, longopts, &longind)) != -1)
switch (opt)
{
case 0: /* a long option without an equivalent short option */
switch (longind)
{
case 0: /* -append */
append = 1;
break;
case 1: /* -truncate */
append = 0;
break;
default: /* something unexpected has happened */
fprintf(stderr,
"%s: "
"getopt_long_only unexpectedly returned %d for `--%s'\n",
progname,
opt,
longopts[longind].name);
return 1;
}
break;
case 'V': /* -version */
version(progname);
return 0;
case 'h': /* -help */
help(progname);
return 0;
case 'r': /* -rotate[=NUM] */
if (optarg)
{
/* we use this while trying to parse a numeric argument */
char ignored;
if (sscanf(optarg,
"%d%c",
&rotate,
&ignored) != 1)
{
fprintf(stderr,
"%s: "
"rotation `%s' is not a number\n",
progname,
optarg);
usage(progname);
return 2;
}
/* normalize rotation */
while (rotate < 0)
{
rotate += 26;
}
rotate %= 26;
}
else
rotate = 13;
break;
case 'o': /* -output=FILE */
outfilename = optarg;
/* we allow "-" as a synonym for stdout here */
if (optarg && !strcmp(optarg, "-"))
{
outfilename = 0;
}
break;
case 'v': /* -verbose[=NUM] */
if (optarg)
{
/* we use this while trying to parse a numeric argument */
char ignored;
if (sscanf(optarg,
"%u%c",
&verbose,
&ignored) != 1)
{
fprintf(stderr,
"%s: "
"verbosity level `%s' is not a number\n",
progname,
optarg);
usage(progname);
return 2;
}
}
else
verbose ++;
break;
case '?': /* getopt_long_only noticed an error */
usage(progname);
return 2;
default: /* something unexpected has happened */
fprintf(stderr,
"%s: "
"getopt_long_only returned an unexpected value (%d)\n",
progname,
opt);
return 1;
}
/* re-open stdout to outfilename, if requested */
if (outfilename)
{
if (! freopen(outfilename, (append ? "a" : "w"), stdout))
{
perror(outfilename);
return 1;
}
}
else
{
/* make a human-readable version of the output filename "-" */
outfilename = "stdout";
/* you can't truncate stdout */
append = 1;
}
if (verbose)
{
fprintf(stderr,
"%s: verbosity level is %u; %s `%s'; rotation %d\n",
progname,
verbose,
(append ? "appending to" : "truncating"),
outfilename,
rotate);
}
if (verbose > 1)
{
fprintf(stderr,
"%s: %d input file(s) were given\n",
progname,
((argc > optind) ? (argc - optind) : 0));
}
if (verbose > 3)
{
fprintf(stderr,
"\topterr: %d\n\toptind: %d\n\toptopt: %d (%c)\n\toptarg: %s\n",
opterr,
optind,
optopt, optopt,
optarg ? optarg : "(null)");
}
/* handle each of the input files (or stdin, if no files were given) */
if (optind < argc)
{
int argindex;
for (argindex = optind; argindex < argc; argindex ++)
{
const char *infilename = argv[argindex];
FILE *infile;
/* we allow "-" as a synonym for stdin here */
if (! strcmp(infilename, "-"))
{
infile = stdin;
infilename = "stdin";
}
else if (! (infile = fopen(infilename, "r")))
{
perror(infilename);
retval = 1;
continue;
}
if (handle(progname,
infile, argv[optind],
stdout, outfilename,
rotate))
{
retval = 1;
fclose(infile);
continue;
}
if ((infile != stdin) && fclose(infile))
{
perror(infilename);
retval = 1;
}
}
}
else
{
retval =
handle(progname,
stdin, "stdin",
stdout, outfilename,
rotate);
}
/* close stdout */
if (fclose(stdout))
{
perror(outfilename);
return 1;
}
if (verbose > 3)
{
fprintf(stderr,
"%s: normal return, exit code is %d\n",
progname,
retval);
}
return retval;
}