install approved copyright notice

[unix-history] / 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 are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley.  The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/

#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     4.6 (Berkeley) %G%";
#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 ERREXIT 0                       /* error exit */
#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;            /* general counter */
       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(ERREXIT);
                       }
               }
               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();
}

/*
* split1 --
*      split by bytes
*/
static
split1()
{
       register long   bcnt;           /* byte counter */
       register int    dist,           /* buffer offset */
                       len;            /* read length */
       register char   *C;             /* tmp pointer into buffer */

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

/*
* split2 --
*      split by lines
*/
static
split2()
{
       register char   *Ce,                    /* start/end pointers */
                       *Cs;
       register long   lcnt;                   /* line counter */
       register int    len;                    /* read length */

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

/*
* newfile --
*      open a new file
*/
static
newfile()
{
       static long     fnum;           /* file name counter */
       static short    defname;        /* using default name, "x" */
       static char     *fpnt;          /* output file name pointer */

       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(ERREXIT);
               }
               ++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
*/
static
usage()
{
       fputs("usage: split [-] [-#] [-b byte_count] [file [prefix]]\n", stderr);
       exit(ERREXIT);
}