/*
 * Copyright (c) 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Kevin Fall.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * @(#) Copyright (c) 1989, 1993 The Regents of the University of California.  All rights reserved.
 * @(#)cat.c    8.2 (Berkeley) 4/27/95
 * $FreeBSD: src/bin/cat/cat.c,v 1.14.2.8 2002/06/29 05:09:26 tjr Exp $
 * $DragonFly: src/bin/cat/cat.c,v 1.16 2007/02/04 21:06:34 pavalos Exp $
 */

#include <sys/param.h>
#include <sys/stat.h>
#ifndef NO_UDOM_SUPPORT
#include <sys/socket.h>
#include <sys/un.h>
#include <errno.h>
#endif

#include <ctype.h>
#include <err.h>
#include <fcntl.h>
#include <locale.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

static int bflag, eflag, nflag, sflag, tflag, vflag, rval;
static const char *filename;

static void     scanfiles(char **, int);
static void     cook_cat(FILE *);
static void     raw_cat(int);

#ifndef NO_UDOM_SUPPORT
static int      udom_open(const char *, int);
#endif

static void
usage(void)
{
        fprintf(stderr,
                "usage: cat [-benstuv] [file ...]\n");
        exit(EXIT_FAILURE);
}

int
main(int argc, char **argv)
{
        int ch;

        setlocale(LC_CTYPE, "");

        while ((ch = getopt(argc, argv, "benstuv")) != -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 't':
                        tflag = vflag = 1;      /* -t implies -v */
                        break;
                case 'u':
                        setbuf(stdout, NULL);
                        break;
                case 'v':
                        vflag = 1;
                        break;
                default:
                        usage();
                        /* NOTREACHED */
                }
        argv += optind;

        if (bflag || eflag || nflag || sflag || tflag || vflag)
                scanfiles(argv, 1);
        else
                scanfiles(argv, 0);
        if (fclose(stdout))
                err(1, "stdout");
        exit(rval);
        /* NOTREACHED */
}

static void
scanfiles(char **argv, int cooked)
{
        char *path;
        FILE *fp;
        int fd;
        int i;

        i = 0;

        while ((path = argv[i]) != NULL || i == 0) {
                if (path == NULL || strcmp(path, "-") == 0) {
                        filename = "stdin";
                        fd = STDIN_FILENO;
                } else {
                        filename = path;
                        fd = open(path, O_RDONLY);
#ifndef NO_UDOM_SUPPORT
                        if (fd < 0 && errno == EOPNOTSUPP)
                                fd = udom_open(path, O_RDONLY);
#endif
                }
                if (fd < 0) {
                        warn("%s", path);
                        rval = 1;
                } else if (cooked) {
                        if (fd == STDIN_FILENO) {
                                cook_cat(stdin);
                        } else {
                                fp = fdopen(fd, "r");
                                if (fp == NULL)
                                        err(1, "%s", path);
                                cook_cat(fp);
                                fclose(fp);
                        }
                } else {
                        raw_cat(fd);
                        if (fd != STDIN_FILENO)
                                close(fd);
                }
                if (path == NULL)
                        break;
                ++i;
        }
}

static void
cook_cat(FILE *fp)
{
        int ch, gobble, line, prev;

        /* Reset EOF condition on stdin. */
        if (fp == stdin && feof(stdin))
                clearerr(stdin);

        line = gobble = 0;
        for (prev = '\n'; (ch = getc(fp)) != EOF; prev = ch) {
                if (prev == '\n') {
                        if (sflag) {
                                if (ch == '\n') {
                                        if (gobble)
                                                continue;
                                        gobble = 1;
                                } else
                                        gobble = 0;
                        }
                        if (nflag) {
                                if (!bflag || ch != '\n') {
                                        fprintf(stdout, "%6d\t", ++line);
                                        if (ferror(stdout))
                                                break;
                                } else if (eflag) {
                                        fprintf(stdout, "%6s\t", "");
                                        if (ferror(stdout))
                                                break;
                                }
                        }
                }
                if (ch == '\n') {
                        if (eflag && putchar('$') == EOF)
                                break;
                } else if (ch == '\t') {
                        if (tflag) {
                                if (putchar('^') == EOF || putchar('I') == EOF)
                                        break;
                                continue;
                        }
                } else if (vflag) {
                        if (!isascii(ch) && !isprint(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");
}

static void
raw_cat(int rfd)
{
        int off;
        size_t nbsize;
        ssize_t nr, nw;
        struct stat rst;
        static struct stat ost;
        static size_t bsize;
        static char *buf;

        /*
         * Figure out the block size to use.  Use the larger of stdout vs
         * the passed descriptor.  The minimum blocksize we use is BUFSIZ.
         */
        if (ost.st_blksize == 0) {
                if (fstat(STDOUT_FILENO, &ost))
                        err(1, "<stdout>");
                if (ost.st_blksize < BUFSIZ)
                        ost.st_blksize = BUFSIZ;
        }
        /*
         * note: rst.st_blksize can be 0, but it is handled ok.
         */
        if (fstat(rfd, &rst))
                err(1, "%s", filename);

        nbsize = MAX(ost.st_blksize, rst.st_blksize);
        if (bsize != nbsize) {
                bsize = nbsize;
                if ((buf = realloc(buf, bsize)) == NULL)
                        err(1, "malloc failed");
        }
        while ((nr = read(rfd, buf, bsize)) > 0) {
                for (off = 0; nr; nr -= nw, off += nw) {
                        nw = write(STDOUT_FILENO, buf + off, nr);
                        if (nw < 0)
                                err(1, "stdout");
                }
        }
        if (nr < 0) {
                warn("%s", filename);
                rval = 1;
        }
}

#ifndef NO_UDOM_SUPPORT

static int
udom_open(const char *path, int flags)
{
        struct sockaddr_un sou;
        int fd;
        unsigned int len;

        bzero(&sou, sizeof(sou));

        /*
         * Construct the unix domain socket address and attempt to connect
         */
        fd = socket(AF_UNIX, SOCK_STREAM, 0);
        if (fd >= 0) {
                sou.sun_family = AF_UNIX;
                if ((len = strlcpy(sou.sun_path, path,
                    sizeof(sou.sun_path))) >= sizeof(sou.sun_path)) {
                        errno = ENAMETOOLONG;
                        return (-1);
                }
                len = offsetof(struct sockaddr_un, sun_path[len+1]);

                if (connect(fd, (void *)&sou, len) < 0) {
                        close(fd);
                        fd = -1;
                }
        }

        /*
         * handle the open flags by shutting down appropriate directions
         */
        if (fd >= 0) {
                switch (flags & O_ACCMODE) {
                case O_RDONLY:
                        if (shutdown(fd, SHUT_WR) == -1)
                                warn(NULL);
                        break;
                case O_WRONLY:
                        if (shutdown(fd, SHUT_RD) == -1)
                                warn(NULL);
                        break;
                default:
                        break;
                }
        }
        return(fd);
}

#endif