usr/src/usr.bin/split/split.c

/*
 * Copyright (c) 1987 Regents of the University of California.
 * All rights reserved.
 *
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. 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.
 */

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1987 Regents of the University of California.\n\
 All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)split.c     4.8 (Berkeley) 6/1/90";
#endif /* not lint */

#include <sys/param.h>
#include <sys/file.h>
#include <stdio.h>
#include <ctype.h>

#define DEFLINE 1000                    /* default num lines per file */
#define ERR     -1                      /* general error */
#define NO      0                       /* no/false */
#define OK      0                       /* okay exit */
#define YES     1                       /* yes/true */

static long     bytecnt,                /* byte count to split on */
                numlines;               /* lines in each file */
static int      ifd = ERR,              /* input file descriptor */
                ofd = ERR;              /* output file descriptor */
static short    file_open;              /* if a file open */
static char     bfr[MAXBSIZE],          /* I/O buffer */
                fname[MAXPATHLEN];      /* file name */

main(argc, argv)
        int argc;
        char **argv;
{
        register int cnt;
        long atol();
        char *strcpy();

        for (cnt = 1; cnt < argc; ++cnt) {
                if (argv[cnt][0] == '-')
                        switch(argv[cnt][1]) {
                        case 0:         /* stdin by request */
                                if (ifd != ERR)
                                        usage();
                                ifd = 0;
                                break;
                        case 'b':       /* byte count split */
                                if (numlines)
                                        usage();
                                if (!argv[cnt][2])
                                        bytecnt = atol(argv[++cnt]);
                                else
                                        bytecnt = atol(argv[cnt] + 2);
                                if (bytecnt <= 0) {
                                        fputs("split: byte count must be greater than zero.\n", stderr);
                                        usage();
                                }
                                break;
                        default:
                                if (!isdigit(argv[cnt][1]) || bytecnt)
                                        usage();
                                if ((numlines = atol(argv[cnt] + 1)) <= 0) {
                                        fputs("split: line count must be greater than zero.\n", stderr);
                                        usage();
                                }
                                break;
                        }
                else if (ifd == ERR) {          /* input file */
                        if ((ifd = open(argv[cnt], O_RDONLY, 0)) < 0) {
                                perror(argv[cnt]);
                                exit(1);
                        }
                }
                else if (!*fname)               /* output file prefix */
                        strcpy(fname, argv[cnt]);
                else
                        usage();
        }
        if (ifd == ERR)                         /* stdin by default */
                ifd = 0;
        if (bytecnt)
                split1();
        if (!numlines)
                numlines = DEFLINE;
        split2();
        exit(0);
}

/*
 * split1 --
 *      split by bytes
 */
split1()
{
        register long bcnt;
        register int dist, len;
        register char *C;

        for (bcnt = 0;;)
                switch(len = read(ifd, bfr, MAXBSIZE)) {
                case 0:
                        exit(OK);
                case ERR:
                        perror("read");
                        exit(1);
                default:
                        if (!file_open) {
                                newfile();
                                file_open = YES;
                        }
                        if (bcnt + len >= bytecnt) {
                                dist = bytecnt - bcnt;
                                if (write(ofd, bfr, dist) != dist)
                                        wrerror();
                                len -= dist;
                                for (C = bfr + dist; len >= bytecnt; len -= bytecnt, C += bytecnt) {
                                        newfile();
                                        if (write(ofd, C, (int)bytecnt) != bytecnt)
                                                wrerror();
                                }
                                if (len) {
                                        newfile();
                                        if (write(ofd, C, len) != len)
                                                wrerror();
                                }
                                else
                                        file_open = NO;
                                bcnt = len;
                        }
                        else {
                                bcnt += len;
                                if (write(ofd, bfr, len) != len)
                                        wrerror();
                        }
                }
}

/*
 * split2 --
 *      split by lines
 */
split2()
{
        register char *Ce, *Cs;
        register long lcnt;
        register int len, bcnt;

        for (lcnt = 0;;)
                switch(len = read(ifd, bfr, MAXBSIZE)) {
                case 0:
                        exit(0);
                case ERR:
                        perror("read");
                        exit(1);
                default:
                        if (!file_open) {
                                newfile();
                                file_open = YES;
                        }
                        for (Cs = Ce = bfr; len--; Ce++)
                                if (*Ce == '\n' && ++lcnt == numlines) {
                                        bcnt = Ce - Cs + 1;
                                        if (write(ofd, Cs, bcnt) != bcnt)
                                                wrerror();
                                        lcnt = 0;
                                        Cs = Ce + 1;
                                        if (len)
                                                newfile();
                                        else
                                                file_open = NO;
                                }
                        if (Cs < Ce) {
                                bcnt = Ce - Cs;
                                if (write(ofd, Cs, bcnt) != bcnt)
                                        wrerror();
                        }
                }
}

/*
 * newfile --
 *      open a new file
 */
newfile()
{
        static long fnum;
        static short defname;
        static char *fpnt;

        if (ofd == ERR) {
                if (fname[0]) {
                        fpnt = fname + strlen(fname);
                        defname = NO;
                }
                else {
                        fname[0] = 'x';
                        fpnt = fname + 1;
                        defname = YES;
                }
                ofd = fileno(stdout);
        }
        /*
         * hack to increase max files; original code just wandered through
         * magic characters.  Maximum files is 3 * 26 * 26 == 2028
         */
#define MAXFILES        676
        if (fnum == MAXFILES) {
                if (!defname || fname[0] == 'z') {
                        fputs("split: too many files.\n", stderr);
                        exit(1);
                }
                ++fname[0];
                fnum = 0;
        }
        fpnt[0] = fnum / 26 + 'a';
        fpnt[1] = fnum % 26 + 'a';
        ++fnum;
        if (!freopen(fname, "w", stdout)) {
                fprintf(stderr, "split: unable to write to %s.\n", fname);
                exit(ERR);
        }
}

/*
 * usage --
 *      print usage message and die
 */
usage()
{
        fputs("usage: split [-] [-#] [-b byte_count] [file [prefix]]\n", stderr);
        exit(1);
}

/*
 * wrerror --
 *      write error
 */
wrerror()
{
        perror("split: write");
        exit(1);
}