/*
 * Copyright (c) 1992, Brian Berliner and Jeff Polk
 * Copyright (c) 1989-1992, Brian Berliner
 * 
 * You may distribute under the terms of the GNU General Public License as
 * specified in the README file that comes with the CVS source distribution.
 * 
 * Tag
 * 
 * Add or delete a symbolic name to an RCS file, or a collection of RCS files.
 * Uses the checked out revision in the current directory.
 */

#include "cvs.h"
#include "savecwd.h"

static int check_fileproc PROTO ((void *callerdat, struct file_info *finfo));
static int check_filesdoneproc PROTO ((void *callerdat, int err,
				       char *repos, char *update_dir,
				       List *entries));
static int pretag_proc PROTO((char *repository, char *filter));
static void masterlist_delproc PROTO((Node *p));
static void tag_delproc PROTO((Node *p));
static int pretag_list_proc PROTO((Node *p, void *closure));

static Dtype tag_dirproc PROTO ((void *callerdat, char *dir,
				 char *repos, char *update_dir,
				 List *entries));
static int tag_fileproc PROTO ((void *callerdat, struct file_info *finfo));
static int tag_filesdoneproc PROTO ((void *callerdat, int err,
				     char *repos, char *update_dir,
				     List *entries));

static char *numtag;
static char *date = NULL;
static char *symtag;
static int delete_flag;			/* adding a tag by default */
static int branch_mode;			/* make an automagic "branch" tag */
static int local;			/* recursive by default */
static int force_tag_match = 1;         /* force tag to match by default */
static int force_tag_move;		/* don't force tag to move by default */
static int check_uptodate;		/* no uptodate-check by default */

struct tag_info
{
    Ctype status;
    char *rev;
    char *tag;
    char *options;
};

struct master_lists
{
    List *tlist;
};

static List *mtlist;
static List *tlist;

static const char *const tag_usage[] =
{
    "Usage: %s %s [-lRF] [-b] [-d] [-c] [-r rev|-D date] tag [files...]\n",
    "\t-l\tLocal directory only, not recursive.\n",
    "\t-R\tProcess directories recursively.\n",
    "\t-d\tDelete the given tag.\n",
    "\t-r rev\tExisting revision/tag.\n",
    "\t-D\tExisting date.\n",
    "\t-f\tForce a head revision if specified tag not found.\n",
    "\t-b\tMake the tag a \"branch\" tag, allowing concurrent development.\n",
    "\t-F\tMove tag if it already exists.\n",
    "\t-c\tCheck that working files are unmodified.\n",
    "(Specify the --help global option for a list of other help options)\n",
    NULL
};

int
cvstag (argc, argv)
    int argc;
    char **argv;
{
    int c;
    int err = 0;

    if (argc == -1)
	usage (tag_usage);

    optind = 0;
    while ((c = getopt (argc, argv, "+FQqlRcdr:D:bf")) != -1)
    {
	switch (c)
	{
	    case 'Q':
	    case 'q':
#ifdef SERVER_SUPPORT
		/* The CVS 1.5 client sends these options (in addition to
		   Global_option requests), so we must ignore them.  */
		if (!server_active)
#endif
		    error (1, 0,
			   "-q or -Q must be specified before \"%s\"",
			   command_name);
		break;
	    case 'l':
		local = 1;
		break;
	    case 'R':
		local = 0;
		break;
	    case 'd':
		delete_flag = 1;
		break;
	    case 'c':
		check_uptodate = 1;
		break;
            case 'r':
                numtag = optarg;
                break;
            case 'D':
                if (date)
                    free (date);
                date = Make_Date (optarg);
                break;
	    case 'f':
		force_tag_match = 0;
		break;
	    case 'b':
		branch_mode = 1;
		break;
            case 'F':
		force_tag_move = 1;
		break;
	    case '?':
	    default:
		usage (tag_usage);
		break;
	}
    }
    argc -= optind;
    argv += optind;

    if (argc == 0)
	usage (tag_usage);
    symtag = argv[0];
    argc--;
    argv++;

    if (date && numtag)
	error (1, 0, "-r and -D options are mutually exclusive");
    if (delete_flag && branch_mode)
	error (0, 0, "warning: -b ignored with -d options");
    RCS_check_tag (symtag);

#ifdef CLIENT_SUPPORT
    if (client_active)
    {
	/* We're the client side.  Fire up the remote server.  */
	start_server ();
	
	ign_setup ();

	if (!force_tag_match)
	    send_arg ("-f");
	if (local)
	    send_arg("-l");
	if (delete_flag)
	    send_arg("-d");
	if (check_uptodate)
	    send_arg("-c");
	if (branch_mode)
	    send_arg("-b");
	if (force_tag_move)
	    send_arg("-F");

	if (numtag)
	    option_with_arg ("-r", numtag);
	if (date)
	    client_senddate (date);

	send_arg (symtag);

	send_files (argc, argv, local, 0,

		    /* I think the -c case is like "cvs status", in
		       which we really better be correct rather than
		       being fast; it is just too confusing otherwise.  */
		    check_uptodate ? 0 : SEND_NO_CONTENTS);
	send_file_names (argc, argv, SEND_EXPAND_WILD);
	send_to_server ("tag\012", 0);
        return get_responses_and_close ();
    }
#endif

    if (numtag != NULL)
	tag_check_valid (numtag, argc, argv, local, 0, "");

    /* check to make sure they are authorized to tag all the 
       specified files in the repository */

    mtlist = getlist();
    err = start_recursion (check_fileproc, check_filesdoneproc,
                           (DIRENTPROC) NULL, (DIRLEAVEPROC) NULL, NULL,
                           argc, argv, local, W_LOCAL, 0, 1,
                           (char *) NULL, 1);
    
    if (err)
    {
       error (1, 0, "correct the above errors first!");
    }
     
    /* start the recursion processor */
    err = start_recursion (tag_fileproc, tag_filesdoneproc, tag_dirproc,
			   (DIRLEAVEPROC) NULL, NULL, argc, argv, local,
			   W_LOCAL, 0, 0, (char *) NULL, 1);
    dellist(&mtlist);
    return (err);
}

/* check file that is to be tagged */
/* All we do here is add it to our list */

static int
check_fileproc (callerdat, finfo)
    void *callerdat;
    struct file_info *finfo;
{
    char *xdir;
    Node *p;
    Vers_TS *vers;
    
    if (check_uptodate) 
    {
	Ctype status = Classify_File (finfo, (char *) NULL, (char *) NULL,
				      (char *) NULL, 1, 0, &vers, 0);
	if ((status != T_UPTODATE) && (status != T_CHECKOUT))
	{
	    error (0, 0, "%s is locally modified", finfo->fullname);
	    freevers_ts (&vers);
	    return (1);
	}
    }
    else
	vers = Version_TS (finfo, NULL, NULL, NULL, 0, 0);
    
    if (finfo->update_dir[0] == '\0')
	xdir = ".";
    else
	xdir = finfo->update_dir;
    if ((p = findnode (mtlist, xdir)) != NULL)
    {
	tlist = ((struct master_lists *) p->data)->tlist;
    }
    else
    {
	struct master_lists *ml;
        
	tlist = getlist ();
	p = getnode ();
	p->key = xstrdup (xdir);
	p->type = UPDATE;
	ml = (struct master_lists *)
	    xmalloc (sizeof (struct master_lists));
	ml->tlist = tlist;
	p->data = (char *) ml;
	p->delproc = masterlist_delproc;
	(void) addnode (mtlist, p);
    }
    /* do tlist */
    p = getnode ();
    p->key = xstrdup (finfo->file);
    p->type = UPDATE;
    p->delproc = tag_delproc;
    if (vers->srcfile == NULL)
    {
        if (!really_quiet)
	    error (0, 0, "nothing known about %s", finfo->file);
	freevers_ts (&vers);
	freenode (p);
	return (1);
    }

    /* Here we duplicate the calculation in tag_fileproc about which
       version we are going to tag.  There probably are some subtle races
       (e.g. numtag is "foo" which gets moved between here and
       tag_fileproc).  */
    if (numtag == NULL && date == NULL)
	p->data = xstrdup (vers->vn_user);
    else
	p->data = RCS_getversion (vers->srcfile, numtag, date,
				  force_tag_match, NULL);

    if (p->data != NULL)
    {
        int addit = 1;
        char *oversion;
        
        oversion = RCS_getversion (vers->srcfile, symtag, (char *) NULL, 1,
				   (int *) NULL);
        if (oversion == NULL) 
        {
            if (delete_flag)
            {
		/* Deleting a tag which did not exist is a noop and
		   should not be logged.  */
                addit = 0;
            }
        }
	else if (delete_flag)
	{
	    free (p->data);
	    p->data = xstrdup (oversion);
	}
        else if (strcmp(oversion, p->data) == 0)
        {
            addit = 0;
        }
        else if (!force_tag_move)
        {
            addit = 0;
        }
        if (oversion != NULL)
        {
            free(oversion);
        }
        if (!addit)
        {
            free(p->data);
            p->data = NULL;
        }
    }
    freevers_ts(&vers);
    (void) addnode (tlist, p);
    return (0);
}
                         
static int
check_filesdoneproc (callerdat, err, repos, update_dir, entries)
    void *callerdat;
    int err;
    char *repos;
    char *update_dir;
    List *entries;
{
    int n;
    Node *p;

    p = findnode(mtlist, update_dir);
    if (p != NULL)
    {
        tlist = ((struct master_lists *) p->data)->tlist;
    }
    else
    {
        tlist = (List *) NULL;
    }
    if ((tlist == NULL) || (tlist->list->next == tlist->list))
    {
        return (err);
    }
    if ((n = Parse_Info(CVSROOTADM_TAGINFO, repos, pretag_proc, 1)) > 0)
    {
        error (0, 0, "Pre-tag check failed");
        err += n;
    }
    return (err);
}

static int
pretag_proc(repository, filter)
    char *repository;
    char *filter;
{
    if (filter[0] == '/')
    {
        char *s, *cp;

        s = xstrdup(filter);
        for (cp=s; *cp; cp++)
        {
            if (isspace ((unsigned char) *cp))
            {
                *cp = '\0';
                break;
            }
        }
        if (!isfile(s))
        {
            error (0, errno, "cannot find pre-tag filter '%s'", s);
            free(s);
            return (1);
        }
        free(s);
    }
    run_setup (filter);
    run_arg (symtag);
    run_arg (delete_flag ? "del" : force_tag_move ? "mov" : "add");
    run_arg (repository);
    walklist(tlist, pretag_list_proc, NULL);
    return (run_exec (RUN_TTY, RUN_TTY, RUN_TTY, RUN_NORMAL));
}

static void
masterlist_delproc(p)
    Node *p;
{
    struct master_lists *ml;

    ml = (struct master_lists *)p->data;
    dellist(&ml->tlist);
    free(ml);
    return;
}

static void
tag_delproc(p)
    Node *p;
{
    if (p->data != NULL)
    {
        free(p->data);
        p->data = NULL;
    }
    return;
}

static int
pretag_list_proc(p, closure)
    Node *p;
    void *closure;
{
    if (p->data != NULL)
    {
        run_arg(p->key);
        run_arg(p->data);
    }
    return (0);
}


/*
 * Called to tag a particular file (the currently checked out version is
 * tagged with the specified tag - or the specified tag is deleted).
 */
/* ARGSUSED */
static int
tag_fileproc (callerdat, finfo)
    void *callerdat;
    struct file_info *finfo;
{
    char *version, *oversion;
    char *nversion = NULL;
    char *rev;
    Vers_TS *vers;
    int retcode = 0;

    /* Lock the directory if it is not already locked.  We can't rely
       on tag_dirproc because it won't handle the case where the user
       specifies a list of files on the command line.  */
    /* We do not need to acquire a full write lock for the tag operation:
       the revisions are obtained from the working directory, so we do not
       require consistency across the entire repository.  However, we do
       need to prevent simultaneous tag operations from interfering with
       each other.  Therefore, we write lock each directory as we enter
       it, and unlock it as we leave it.  */
    lock_dir_for_write (finfo->repository);

    vers = Version_TS (finfo, NULL, NULL, NULL, 0, 0);

    if ((numtag != NULL) || (date != NULL))
    {
        nversion = RCS_getversion(vers->srcfile,
                                  numtag,
                                  date,
                                  force_tag_match,
				  (int *) NULL);
        if (nversion == NULL)
        {
	    freevers_ts (&vers);
            return (0);
        }
    }
    if (delete_flag)
    {

	/*
	 * If -d is specified, "force_tag_match" is set, so that this call to
	 * RCS_getversion() will return a NULL version string if the symbolic
	 * tag does not exist in the RCS file.
	 * 
	 * This is done here because it's MUCH faster than just blindly calling
	 * "rcs" to remove the tag... trust me.
	 */

	version = RCS_getversion (vers->srcfile, symtag, (char *) NULL, 1,
				  (int *) NULL);
	if (version == NULL || vers->srcfile == NULL)
	{
	    freevers_ts (&vers);
	    return (0);
	}
	free (version);

	if ((retcode = RCS_deltag(vers->srcfile, symtag)) != 0) 
	{
	    if (!quiet)
		error (0, retcode == -1 ? errno : 0,
		       "failed to remove tag %s from %s", symtag,
		       vers->srcfile->path);
	    freevers_ts (&vers);
	    return (1);
	}
	RCS_rewrite (vers->srcfile, NULL, NULL);

	/* warm fuzzies */
	if (!really_quiet)
	{
	    cvs_output ("D ", 2);
	    cvs_output (finfo->fullname, 0);
	    cvs_output ("\n", 1);
	}

	freevers_ts (&vers);
	return (0);
    }

    /*
     * If we are adding a tag, we need to know which version we have checked
     * out and we'll tag that version.
     */
    if (nversion == NULL)
    {
        version = vers->vn_user;
    }
    else
    {
        version = nversion;
    }
    if (version == NULL)
    {
	freevers_ts (&vers);
	return (0);
    }
    else if (strcmp (version, "0") == 0)
    {
	if (!quiet)
	    error (0, 0, "couldn't tag added but un-commited file `%s'", finfo->file);
	freevers_ts (&vers);
	return (0);
    }
    else if (version[0] == '-')
    {
	if (!quiet)
	    error (0, 0, "skipping removed but un-commited file `%s'", finfo->file);
	freevers_ts (&vers);
	return (0);
    }
    else if (vers->srcfile == NULL)
    {
	if (!quiet)
	    error (0, 0, "cannot find revision control file for `%s'", finfo->file);
	freevers_ts (&vers);
	return (0);
    }

    /*
     * As an enhancement for the case where a tag is being re-applied to a
     * large number of files, make one extra call to RCS_getversion to see
     * if the tag is already set in the RCS file.  If so, check to see if it
     * needs to be moved.  If not, do nothing.  This will likely save a lot of
     * time when simply moving the tag to the "current" head revisions of a
     * module -- which I have found to be a typical tagging operation.
     */
    rev = branch_mode ? RCS_magicrev (vers->srcfile, version) : version;
    oversion = RCS_getversion (vers->srcfile, symtag, (char *) NULL, 1,
			       (int *) NULL);
    if (oversion != NULL)
    {
	int isbranch = RCS_nodeisbranch (finfo->rcs, symtag);

	/*
	 * if versions the same and neither old or new are branches don't have 
	 * to do anything
	 */
	if (strcmp (version, oversion) == 0 && !branch_mode && !isbranch)
	{
	    free (oversion);
	    if (branch_mode)
		free (rev);
	    freevers_ts (&vers);
	    return (0);
	}

	if (!force_tag_move)
	{
	    /* we're NOT going to move the tag */
	    cvs_output ("W ", 2);
	    cvs_output (finfo->fullname, 0);
	    cvs_output (" : ", 0);
	    cvs_output (symtag, 0);
	    cvs_output (" already exists on ", 0);
	    cvs_output (isbranch ? "branch" : "version", 0);
	    cvs_output (" ", 0);
	    cvs_output (oversion, 0);
	    cvs_output (" : NOT MOVING tag to ", 0);
	    cvs_output (branch_mode ? "branch" : "version", 0);
	    cvs_output (" ", 0);
	    cvs_output (rev, 0);
	    cvs_output ("\n", 1);
	    free (oversion);
	    if (branch_mode)
		free (rev);
	    freevers_ts (&vers);
	    return (0);
	}
	free (oversion);
    }

    if ((retcode = RCS_settag(vers->srcfile, symtag, rev)) != 0)
    {
	error (1, retcode == -1 ? errno : 0,
	       "failed to set tag %s to revision %s in %s",
	       symtag, rev, vers->srcfile->path);
	if (branch_mode)
	    free (rev);
	freevers_ts (&vers);
	return (1);
    }
    if (branch_mode)
	free (rev);
    RCS_rewrite (vers->srcfile, NULL, NULL);

    /* more warm fuzzies */
    if (!really_quiet)
    {
	cvs_output ("T ", 2);
	cvs_output (finfo->fullname, 0);
	cvs_output ("\n", 1);
    }

    if (nversion != NULL)
    {
        free (nversion);
    }
    freevers_ts (&vers);
    return (0);
}

/* Clear any lock we may hold on the current directory.  */

static int
tag_filesdoneproc (callerdat, err, repos, update_dir, entries)
    void *callerdat;
    int err;
    char *repos;
    char *update_dir;
    List *entries;
{
    Lock_Cleanup ();

    return (err);
}

/*
 * Print a warm fuzzy message
 */
/* ARGSUSED */
static Dtype
tag_dirproc (callerdat, dir, repos, update_dir, entries)
    void *callerdat;
    char *dir;
    char *repos;
    char *update_dir;
    List *entries;
{
    if (!quiet)
	error (0, 0, "%s %s", delete_flag ? "Untagging" : "Tagging", update_dir);
    return (R_PROCESS);
}

/* Code relating to the val-tags file.  Note that this file has no way
   of knowing when a tag has been deleted.  The problem is that there
   is no way of knowing whether a tag still exists somewhere, when we
   delete it some places.  Using per-directory val-tags files (in
   CVSREP) might be better, but that might slow down the process of
   verifying that a tag is correct (maybe not, for the likely cases,
   if carefully done), and/or be harder to implement correctly.  */

struct val_args {
    char *name;
    int found;
};

static int val_fileproc PROTO ((void *callerdat, struct file_info *finfo));

static int
val_fileproc (callerdat, finfo)
    void *callerdat;
    struct file_info *finfo;
{
    RCSNode *rcsdata;
    struct val_args *args = (struct val_args *)callerdat;
    char *tag;

    if ((rcsdata = finfo->rcs) == NULL)
	/* Not sure this can happen, after all we passed only
	   W_REPOS | W_ATTIC.  */
	return 0;

    tag = RCS_gettag (rcsdata, args->name, 1, (int *) NULL);
    if (tag != NULL)
    {
	/* FIXME: should find out a way to stop the search at this point.  */
	args->found = 1;
	free (tag);
    }
    return 0;
}

static Dtype val_direntproc PROTO ((void *, char *, char *, char *, List *));

static Dtype
val_direntproc (callerdat, dir, repository, update_dir, entries)
    void *callerdat;
    char *dir;
    char *repository;
    char *update_dir;
    List *entries;
{
    /* This is not quite right--it doesn't get right the case of "cvs
       update -d -r foobar" where foobar is a tag which exists only in
       files in a directory which does not exist yet, but which is
       about to be created.  */
    if (isdir (dir))
	return R_PROCESS;
    return R_SKIP_ALL;
}

/* Check to see whether NAME is a valid tag.  If so, return.  If not
   print an error message and exit.  ARGC, ARGV, LOCAL, and AFLAG specify
   which files we will be operating on.

   REPOSITORY is the repository if we need to cd into it, or NULL if
   we are already there, or "" if we should do a W_LOCAL recursion.
   Sorry for three cases, but the "" case is needed in case the
   working directories come from diverse parts of the repository, the
   NULL case avoids an unneccesary chdir, and the non-NULL, non-""
   case is needed for checkout, where we don't want to chdir if the
   tag is found in CVSROOTADM_VALTAGS, but there is not (yet) any
   local directory.  */
void
tag_check_valid (name, argc, argv, local, aflag, repository)
    char *name;
    int argc;
    char **argv;
    int local;
    int aflag;
    char *repository;
{
    DBM *db;
    char *valtags_filename;
    int err;
    datum mytag;
    struct val_args the_val_args;
    struct saved_cwd cwd;
    int which;

    /* Numeric tags require only a syntactic check.  */
    if (isdigit ((unsigned char) name[0]))
    {
	char *p;
	for (p = name; *p != '\0'; ++p)
	{
	    if (!(isdigit ((unsigned char) *p) || *p == '.'))
		error (1, 0, "\
Numeric tag %s contains characters other than digits and '.'", name);
	}
	return;
    }

    /* Special tags are always valid.  */
    if (strcmp (name, TAG_BASE) == 0
	|| strcmp (name, TAG_HEAD) == 0)
	return;

    /* FIXME: This routine doesn't seem to do any locking whatsoever
       (and it is called from places which don't have locks in place).
       If two processes try to write val-tags at the same time, it would
       seem like we are in trouble.  */

    mytag.dptr = name;
    mytag.dsize = strlen (name);

    valtags_filename = xmalloc (strlen (CVSroot_directory)
				+ sizeof CVSROOTADM
				+ sizeof CVSROOTADM_VALTAGS + 20);
    strcpy (valtags_filename, CVSroot_directory);
    strcat (valtags_filename, "/");
    strcat (valtags_filename, CVSROOTADM);
    strcat (valtags_filename, "/");
    strcat (valtags_filename, CVSROOTADM_VALTAGS);
    db = dbm_open (valtags_filename, O_RDWR, 0666);
    if (db == NULL)
    {
	if (!existence_error (errno))
	    error (1, errno, "cannot read %s", valtags_filename);

	/* If the file merely fails to exist, we just keep going and create
	   it later if need be.  */
    }
    else
    {
	datum val;

	val = dbm_fetch (db, mytag);
	if (val.dptr != NULL)
	{
	    /* Found.  The tag is valid.  */
	    dbm_close (db);
	    free (valtags_filename);
	    return;
	}
	/* FIXME: should check errors somehow (add dbm_error to myndbm.c?).  */
    }

    /* We didn't find the tag in val-tags, so look through all the RCS files
       to see whether it exists there.  Yes, this is expensive, but there
       is no other way to cope with a tag which might have been created
       by an old version of CVS, from before val-tags was invented.

       Since we need this code anyway, we also use it to create
       entries in val-tags in general (that is, the val-tags entry
       will get created the first time the tag is used, not when the
       tag is created).  */

    the_val_args.name = name;
    the_val_args.found = 0;

    which = W_REPOS | W_ATTIC;

    if (repository != NULL)
    {
	if (repository[0] == '\0')
	    which |= W_LOCAL;
	else
	{
	    if (save_cwd (&cwd))
		error_exit ();
	    if ( CVS_CHDIR (repository) < 0)
		error (1, errno, "cannot change to %s directory", repository);
	}
    }

    err = start_recursion (val_fileproc, (FILESDONEPROC) NULL,
			   val_direntproc, (DIRLEAVEPROC) NULL,
			   (void *)&the_val_args,
			   argc, argv, local, which, aflag,
			   1, NULL, 1);
    if (repository != NULL && repository[0] != '\0')
    {
	if (restore_cwd (&cwd, NULL))
	    exit (EXIT_FAILURE);
	free_cwd (&cwd);
    }

    if (!the_val_args.found)
	error (1, 0, "no such tag %s", name);
    else
    {
	/* The tags is valid but not mentioned in val-tags.  Add it.  */
	datum value;

	if (noexec)
	{
	    if (db != NULL)
		dbm_close (db);
	    free (valtags_filename);
	    return;
	}

	if (db == NULL)
	{
	    mode_t omask;
	    omask = umask (cvsumask);
	    db = dbm_open (valtags_filename, O_RDWR | O_CREAT | O_TRUNC, 0666);
	    (void) umask (omask);

	    if (db == NULL)
	    {
		error (0, errno, "cannot create %s", valtags_filename);
		free (valtags_filename);
		return;
	    }
	}
	value.dptr = "y";
	value.dsize = 1;
	if (dbm_store (db, mytag, value, DBM_REPLACE) < 0)
	    error (0, errno, "cannot store %s into %s", name,
		   valtags_filename);
	dbm_close (db);
    }
    free (valtags_filename);
}

/*
 * Check whether a join tag is valid.  This is just like
 * tag_check_valid, but we must stop before the colon if there is one.
 */

void
tag_check_valid_join (join_tag, argc, argv, local, aflag, repository)
     char *join_tag;
     int argc;
     char **argv;
     int local;
     int aflag;
     char *repository;
{
    char *c, *s;

    c = xstrdup (join_tag);
    s = strchr (c, ':');
    if (s != NULL)
    {
        if (isdigit ((unsigned char) join_tag[0]))
	    error (1, 0,
		   "Numeric join tag %s may not contain a date specifier",
		   join_tag);

        *s = '\0';
	/* hmmm...  I think it makes sense to allow -j:<date>, but
	 * for now this fixes a bug where CVS just spins and spins (I
	 * think in the RCS code) looking for a zero length tag.
	 */
	if (!*c)
	    error (1, 0,
		   "argument to join may not contain a date specifier without a tag");
    }

    tag_check_valid (c, argc, argv, local, aflag, repository);

    free (c);
}
