use FTS_COMFOLLOW flag to follow symlinks unless -l, -d, or -F

[unix-history] / usr / src / bin / ls / ls.c

/*
* Copyright (c) 1989 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Michael Fischbein.
*
* %sccs.include.redist.c%
*/

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1989 The Regents of the University of California.\n\
All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)ls.c        5.56 (Berkeley) %G%";
#endif /* not lint */

#include <sys/types.h>  
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <fts.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <stdio.h>
#include "ls.h"
#include "extern.h"

void    display __P((int, FTSENT *, FTSENT *));
int     mastercmp __P((const FTSENT **, const FTSENT **));
void    traverse __P((int, char **, int));

static void (*printfcn) __P((FTSENT *, int, u_long, int));
static int (*sortfcn) __P((const FTSENT *, const FTSENT *));

int termwidth = 80;             /* default terminal width */

/* flags */
int f_accesstime;               /* use time of last access */
int f_column;                   /* columnated format */
int f_group;                    /* show group ownership of a file */
int f_flags;                    /* show flags associated with a file */
int f_inode;                    /* print inode */
int f_kblocks;                  /* print size in kilobytes */
int f_listdir;                  /* list actual directory, not contents */
int f_listdot;                  /* list files beginning with . */
int f_longform;                 /* long listing format */
int f_newline;                  /* if precede with newline */
int f_nonprint;                 /* show unprintables as ? */
int f_nosort;                   /* don't sort output */
int f_recursive;                /* ls subdirectories also */
int f_reversesort;              /* reverse whatever sort is used */
int f_sectime;                  /* print the real time for all files */
int f_singlecol;                /* use single column output */
int f_size;                     /* list size in short listing */
int f_statustime;               /* use time of last mode change */
int f_dirname;                  /* if precede with directory name */
int f_timesort;                 /* sort by time vice name */
int f_type;                     /* add type character for non-regular files */

int
main(argc, argv)
       int argc;
       char *argv[];
{
       struct winsize win;
       int ch, fts_options;
       char *p;

       /* Terminal defaults to -Cq, non-terminal defaults to -1. */
       if (isatty(1)) {
               f_nonprint = 1;
               if (ioctl(1, TIOCGWINSZ, &win) == -1 || !win.ws_col) {
                       if (p = getenv("COLUMNS"))
                               termwidth = atoi(p);
               }
               else
                       termwidth = win.ws_col;
               f_column = 1;
       } else
               f_singlecol = 1;

       /* Root is -A automatically. */
       if (!getuid())
               f_listdot = 1;

       fts_options = FTS_PHYSICAL;
       while ((ch = getopt(argc, argv, "1ACFLRTacdfgikloqrstu")) != EOF) {
               switch (ch) {
               /*
                * The -1, -C and -l options all override each other so shell
                * aliasing works right.
                */
               case '1':
                       f_singlecol = 1;
                       f_column = f_longform = 0;
                       break;
               case 'C':
                       f_column = 1;
                       f_longform = f_singlecol = 0;
                       break;
               case 'l':
                       f_longform = 1;
                       f_column = f_singlecol = 0;
                       break;
               /* -c and -u override each other */
               case 'c':
                       f_statustime = 1;
                       f_accesstime = 0;
                       break;
               case 'u':
                       f_accesstime = 1;
                       f_statustime = 0;
                       break;
               case 'F':
                       f_type = 1;
                       break;
               case 'L':
                       fts_options &= ~FTS_PHYSICAL;
                       fts_options |= FTS_LOGICAL;
                       break;
               case 'R':
                       f_recursive = 1;
                       break;
               case 'a':
                       fts_options |= FTS_SEEDOT;
                       /* FALLTHROUGH */
               case 'A':
                       f_listdot = 1;
                       break;
               case 'S':
                       Sflg++; /* fall into... */
               case 'd':
                       f_listdir = 1;
                       break;
               case 'f':
                       f_nosort = 1;
                       break;
               case 'g':
                       f_group = 1;
                       break;
               case 'i':
                       f_inode = 1;
                       break;
               case 'k':
                       f_kblocks = 1;
                       break;
               case 'o':
                       f_flags = 1;
                       break;
               case 'q':
                       f_nonprint = 1;
                       break;
               case 'r':
                       f_reversesort = 1;
                       break;
               case 's':
                       f_size = 1;
                       break;
               case 'T':
                       f_sectime = 1;
                       break;
               case 't':
                       f_timesort = 1;
                       break;
               default:
               case '?':
                       usage();
               }
       }
       argc -= optind;
       argv += optind;

       /* The -d option turns off the -R option. */
       if (f_listdir)
               f_recursive = 0;

       /* If not -F, -l -s or -t options, don't require stat information. */
       if (!f_longform && !f_size && !f_timesort && !f_type)
               fts_options |= FTS_NOSTAT;

       /*
        * If not -F, -d or -l options, follow any symbolic links listed on
        * the command line.
        */
       if (!f_longform && !f_listdir && !f_type)
               fts_options |= FTS_COMFOLLOW;

       /* Select a sort function. */
       if (f_reversesort) {
               if (!f_timesort)
                       sortfcn = revnamecmp;
               else if (f_accesstime)
                       sortfcn = revacccmp;
               else if (f_statustime)
                       sortfcn = revstatcmp;
               else /* Use modification time. */
                       sortfcn = revmodcmp;
       } else {
               if (!f_timesort)
                       sortfcn = namecmp;
               else if (f_accesstime)
                       sortfcn = acccmp;
               else if (f_statustime)
                       sortfcn = statcmp;
               else /* Use modification time. */
                       sortfcn = modcmp;
       }

       /* Select a print function. */
       if (f_singlecol)
               printfcn = printscol;
       else if (f_longform)
               printfcn = printlong;
       else
               printfcn = printcol;

       if (argc)
               traverse(argc, argv, fts_options);
       else {
               static char dot[] = ".", *dotav[] = { dot, NULL };
               traverse(1, dotav, fts_options);
       }
       exit(0);
}

/*
* Traverse() walks the logical directory structure specified by the argv list
* in the order specified by the mastercmp() comparison function.  During the
* traversal it passes linked lists of structures to display() which represent
* a superset (may be exact set) of the files to be displayed.
*/
void
traverse(argc, argv, options)
       int argc, options;
       char *argv[];
{
       register FTS *ftsp;
       register FTSENT *p;
       register int is_ddot;
       
       if ((ftsp =
           fts_open(argv, options, f_nosort ? NULL : mastercmp)) == NULL)
               err(1, "fts_open: %s", strerror(errno));

       display(argc, NULL, fts_children(ftsp));
       if (f_listdir)
               return;
       while (p = fts_read(ftsp))
               switch(p->fts_info) {
               case FTS_DC:
                       err(0, "%s: directory causes a cycle", p->fts_name);
                       break;
               case FTS_DNR:
               case FTS_ERR:
                       err(0, "%s: %s",
                           p->fts_name, strerror(p->fts_errno));
                       break;
               case FTS_D:
                       if (p->fts_level != FTS_ROOTLEVEL &&
                           p->fts_name[0] == '.' && !f_listdot)
                               break;
                       display(argc, p, fts_children(ftsp));
                       if (!f_recursive)
                               (void)fts_set(ftsp, p, FTS_SKIP);
                       break;
               }
       (void)fts_close(ftsp);
}

/*
* Display() takes a linked list of FTSENT structures and based on the flags
* set on the command line passes the list along with any other necessary
* information to the print function (printfcn()).  P always points to the
* parent directory of the display list.
*/
void
display(argc, p, list)
       int argc;
       register FTSENT *p;
       FTSENT *list;
{
       register FTSENT *cur;
       u_long btotal;
       int entries, maxlen;
       
       /*
        * If list is NULL there are two possibilities: that the parent
        * directory p has no children, or that fts_children() returned an
        * error.  We ignore the error case since it will be replicated
        * on the next call to fts_read() on the post-order visit to the
        * directory p, and will be signalled in traverse().
        */
       if (list == NULL && (p->fts_level != FTS_ROOTLEVEL || argc != 1)) {
               (void)printf("\n%s:\n", p->fts_path);
               return;
       }

       /*
        * P can only be NULL if list is the argv list.  This list must be
        * handled slightly differently due to the fact that there does not
        * exist a proper parent directory and different rules apply to it.
        */
       btotal = 0;
       maxlen = 0;
       if (p == NULL)
               for (cur = list, entries = 0; cur; cur = cur->fts_link) {
                       if (cur->fts_info == FTS_ERR ||
                           cur->fts_info == FTS_NS) {
                               err(0, "%s: %s",
                                   cur->fts_name, strerror(cur->fts_errno));
                               cur->fts_number = NO_PRINT;
                               continue;
                       }
                       /*
                        * If cur is a directory, do not print it out now.  Its
                        * contents will be printed out when fts_read() reads
                        * it.
                        */
                       if (cur->fts_info == FTS_D && !f_listdir) {
                               cur->fts_number = NO_PRINT;
                               continue;
                       }
                       ++entries;
                       if (f_nonprint)
                               prcopy(cur->fts_name, cur->fts_name,
                                   cur->fts_namelen);
                       if (f_column && cur->fts_namelen > maxlen)
                               maxlen = cur->fts_namelen;
               }
       else {
               if (p->fts_level != FTS_ROOTLEVEL || argc != 1)
                       (void)printf("\n%s:\n", p->fts_path);
               
               for (cur = list, entries = 0; cur; cur = cur->fts_link) {
                       if (cur->fts_info == FTS_ERR ||
                           cur->fts_info == FTS_NS) {
                               err(0, "%s: %s",
                                   cur->fts_name, strerror(cur->fts_errno));
                               cur->fts_number = NO_PRINT;
                               continue;
                       }
                       /* Don't display dot file if -a/-A not set. */
                       if (cur->fts_name[0] == '.' && !f_listdot) {
                               cur->fts_number = NO_PRINT;
                               continue;
                       }
                       ++entries;
                       if (f_nonprint)
                               prcopy(cur->fts_name, cur->fts_name,
                                      cur->fts_namelen);
                       if (f_column && cur->fts_namelen > maxlen)
                               maxlen = cur->fts_namelen;
                       
                       if (f_longform || f_size)
                               btotal += cur->fts_statp->st_blocks;
               }
       }

       if (entries)
               printfcn(list, entries, btotal, maxlen);
}

/*
* Ordering for mastercmp:
* If ordering the argv (fts_level = FTS_ROOTLEVEL) return non-directories
* as larger than directories.  Within either group, use the sort function.
* All other levels use the sort function.  Error entries remain unsorted.
*/
int
mastercmp(a, b)
       const FTSENT **a, **b;
{
       register int a_info, b_info;

       a_info = (*a)->fts_info;
       if (a_info == FTS_ERR)
               return (0);
       b_info = (*b)->fts_info;
       if (b_info == FTS_ERR)
               return (0);

       if (a_info == FTS_NS || b_info == FTS_NS)
               return (namecmp(*a, *b));

       if (a_info == b_info)  
               return (sortfcn(*a, *b));

       if ((*a)->fts_level == FTS_ROOTLEVEL)
               if (a_info == FTS_D)        
                       return (1);
               else if (b_info == FTS_D)
                       return (-1);
               else
                       return (sortfcn(*a, *b));
       else
               return (sortfcn(*a, *b));
}