Hi,
I tried creating my version of the cat function in bash but left it and now I'm trying to make this function work, but it wouldn't.
#include <sys/param.h>
#include <sys/stat.h>
#include <locale.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
int bflag, eflag, fflag, nflag, sflag, tflag, vflag;
int rval;
const char *filename;
int main __P((int, char *[]));
void cook_args __P((char *argv[]));
void cook_buf __P((FILE *));
void raw_args __P((char *argv[]));
void raw_cat __P((int));
int main(int argc, char* argv[])
{
int ch;
(void)setlocale(LC_ALL, "");
while ((ch = getopt(argc, argv, "befnstuv")) != -1)
switch (ch) {
case 'b':
bflag = nflag = 1; /* -b implies -n */
break;
case 'e':
eflag = vflag = 1; /* -e implies -v */
break;
case 'n':
nflag = 1;
break;
case 's':
sflag = 1;
break;
case 'f':
fflag = 1;
break;
case 't':
tflag = vflag = 1; /* -t implies -v */
break;
case 'u':
setbuf(stdout, (char *)NULL);
break;
case 'v':
vflag = 1;
break;
default:
case '?':
(void)fprintf(stderr,
"usage: cat [-benstuv] [-] [file ...]\n");
exit(1);
/* NOTREACHED */
}
argv += optind;
if (bflag || eflag || nflag || sflag || tflag || vflag)
cook_args(argv);
else
raw_args(argv);
if (fclose(stdout))
err(1, "stdout");
exit(rval);
/* NOTREACHED */
}
void
cook_args(argv)
char **argv;
{
FILE *fp;
fp = stdin;
filename = "stdin";
do {
if (*argv) {
if (!strcmp(*argv, "-"))
fp = stdin;
else if ((fp = fopen(*argv, "rf")) == NULL) {
warn("%s", *argv);
rval = 1;
++argv;
continue;
}
filename = *argv++;
}
cook_buf(fp);
if (fp != stdin)
(void)fclose(fp);
} while (*argv);
}
void
cook_buf(fp)
FILE *fp;
{
int ch, gobble, line, prev;
line = gobble = 0;
for (prev = '\n'; (ch = getc(fp)) != EOF; prev = ch) {
if (prev == '\n') {
if (ch == '\n') {
if (sflag) {
if (!gobble && putchar(ch) == EOF)
break;
gobble = 1;
continue;
}
if (nflag) {
if (!bflag) {
(void)fprintf(stdout,
"%6d\t", ++line);
if (ferror(stdout))
break;
} else if (eflag) {
(void)fprintf(stdout,
"%6s\t", "");
if (ferror(stdout))
break;
}
}
} else if (nflag) {
(void)fprintf(stdout, "%6d\t", ++line);
if (ferror(stdout))
break;
}
}
gobble = 0;
if (ch == '\n') {
if (eflag)
if (putchar('$') == EOF)
break;
} else if (ch == '\t') {
if (tflag) {
if (putchar('^') == EOF || putchar('I') == EOF)
break;
continue;
}
} else if (vflag) {
if (!isascii(ch)) {
if (putchar('M') == EOF || putchar('-') == EOF)
break;
ch = toascii(ch);
}
if (iscntrl(ch)) {
if (putchar('^') == EOF ||
putchar(ch == '\177' ? '?' :
ch | 0100) == EOF)
break;
continue;
}
}
if (putchar(ch) == EOF)
break;
}
if (ferror(fp)) {
warn("%s", filename);
rval = 1;
clearerr(fp);
}
if (ferror(stdout))
err(1, "stdout");
}
void
raw_args(argv)
char **argv;
{
int fd;
fd = fileno(stdin);
filename = "stdin";
do {
if (*argv) {
if (!strcmp(*argv, "-"))
fd = fileno(stdin);
else if (fflag) {
struct stat st;
fd = open(*argv, O_RDONLY|O_NONBLOCK, 0);
if (fd < 0)
goto skip;
if (fstat(fd, &st) == -1) {
close(fd);
goto skip;
}
if (!S_ISREG(st.st_mode)) {
close(fd);
goto skip;
}
}
else if ((fd = open(*argv, O_RDONLY, 0)) < 0) {
skip:
warn("%s", *argv);
rval = 1;
++argv;
continue;
}
filename = *argv++;
}
raw_cat(fd);
if (fd != fileno(stdin))
(void)close(fd);
} while (*argv);
}
void
raw_cat(rfd)
int rfd;
{
int wfd;
static char *buf;
static char fb_buf[BUFSIZ];
struct stat sbuf;
static size_t bsize;
ssize_t nr, nw, off;
wfd = fileno(stdout);
if (buf == NULL) {
if (fstat(wfd, &sbuf) == 0) {
bsize = MIN(sbuf.st_blksize, SSIZE_MAX);
bsize = MAX(bsize, BUFSIZ);
buf = malloc(bsize);
}
if (buf == NULL) {
buf = fb_buf;
bsize = BUFSIZ;
}
}
while ((nr = read(rfd, buf, bsize)) > 0)
for (off = 0; nr; nr -= nw, off += nw)
if ((nw = write(wfd, buf + off, (size_t)nr)) < 0)
err(1, "stdout");
if (nr < 0) {
warn("%s", filename);
rval = 1;
}
}
Does anyone have a suggestion what might be the bug? I can't figure it out and would appreciate any help.