subversion/svnadmin/shell.c - subversion - Git at Google

 /*
  * shell.c:  interactive fs shell for 'svnadmin'
  *
  * ====================================================================
  * Copyright (c) 2000-2002 CollabNet.  All rights reserved.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution.  The terms
  * are also available at http://subversion.tigris.org/license-1.html.
  * If newer versions of this license are posted there, you may use a
  * newer version instead, at your option.
  *
  * This software consists of voluntary contributions made by many
  * individuals.  For exact contribution history, see the revision
  * history and logs, available at http://subversion.tigris.org/.
  * ====================================================================
  */


 #include "svnadmin.h"


 /*** Code ***/

 /* Helper */
 static svn_error_t *
 path_stat (svn_boolean_t *exists,
            svn_stringbuf_t *path,
            shcxt_t *shcxt,
            apr_pool_t *pool)
 {
   apr_hash_t *dirents;
   svn_stringbuf_t *parent, *basename;
   svn_error_t *err;

   /* Sanity check: does path actually exist??  ### oddly, there is no
      'svn_fs_stat', so they only way we can check is by opening its
      -parent- and doing a hash lookup! */

   svn_path_split (path, &parent, &basename, pool);

   err = svn_fs_dir_entries (&dirents, shcxt->root, parent->data, pool);
   if (err)
     {
       *exists = FALSE;
       return SVN_NO_ERROR;
     }

   /* else... */

   if ((apr_hash_get (dirents, basename->data, basename->len))
       || (! strcmp (path->data, "/")))
     *exists = TRUE;
   else
     *exists = FALSE;

   return SVN_NO_ERROR;
 }


 /* Helper: Given a CURRENT_PATH in a SHCXT, and some GIVEN_PATH that
    is either relative to CURRENT_PATH (or absolute), return a
    *NEW_PATH allocated in POOL that is possibly a combination of the
    two.

    Do a sanity check:  if the *NEW_PATH dosen't actually exist in the
    current filesytem revision, then set it to NULL! */
 static svn_error_t *
 compute_new_path (svn_stringbuf_t **new_path,
                   svn_stringbuf_t *current_path,
                   char *given_path,
                   shcxt_t *shcxt,
                   apr_pool_t *pool)
 {
   svn_boolean_t exists;
   svn_stringbuf_t *final_path = svn_stringbuf_dup (current_path, pool);

   if (given_path[0] == '/')
     {
       /* if absolute path, just set final_path to it. */
       svn_stringbuf_setempty (final_path);
       svn_stringbuf_appendcstr (final_path, given_path);
     }
   else if (! strcmp (given_path, ".."))
     {
       /* go up a level */
       svn_path_remove_component (final_path);

       /* our path library is so broken, sigh. */
       if (svn_stringbuf_isempty (final_path))
         svn_stringbuf_appendcstr (final_path, "/");
     }
   else
     {
       /* just append path to cwd */
       svn_path_add_component_nts (final_path, given_path);
     }

   SVN_ERR (path_stat (&exists, final_path, shcxt, pool));
   if (exists)
     *new_path = final_path;
   else
     *new_path = NULL;

   return SVN_NO_ERROR;
 }


 /* ----------------------------------------------------------------*/
 /** Subcommands **/


 static void
 help (void)
 {
   /* make this not suck.  maybe define shell commands in a list
      somewhere, the way it's done with the svn client app. */
   printf ("\nAvailable commands are:\n");

   printf ("   cd:   change directory\n");
   printf ("   cr:   change revision\n");
   printf ("   ls:   list directory entries\n");
   printf (" exit:   leave this shell\n");
 }


 /* Change Directory */
 static svn_error_t *
 cd (char *path,
     shcxt_t *shcxt,
     apr_pool_t *pool)
 {
   if (strlen(path) == 0)
     {
       /* no argument?  change to root dir. */
       svn_stringbuf_setempty (shcxt->cwd);
       svn_stringbuf_appendcstr (shcxt->cwd, "/");
     }
   else
     {
       svn_stringbuf_t *new_path;

       SVN_ERR (compute_new_path (&new_path, shcxt->cwd, path,
                                  shcxt, shcxt->pool));

       if (new_path == NULL)
         printf ("No such object: %s\n", path);
       else
         shcxt->cwd = new_path;
     }

   return SVN_NO_ERROR;
 }


 /* Change Revision;  INVALID revnum means "change to head revision". */
 static svn_error_t *
 cr (svn_revnum_t rev,
     shcxt_t *shcxt,
     apr_pool_t *pool)
 {
   svn_revnum_t youngest;
   svn_boolean_t exists = FALSE;

   SVN_ERR (svn_fs_youngest_rev (&youngest, shcxt->fs, pool));

   if (! SVN_IS_VALID_REVNUM(rev))
     rev = youngest;

   /* sanity check */
   if ((rev < 0) || (rev > youngest))
     {
       /* non-fatal error */
       printf ("There is no revision %ld.\n", (long int) rev);
       return SVN_NO_ERROR;
     }

   /* else... */

   /* close the old root */
   if (shcxt->root != NULL)
     svn_fs_close_root (shcxt->root);

   /* and open the new root */
   shcxt->current_rev = rev;
   SVN_ERR (svn_fs_revision_root (&(shcxt->root),
                                  shcxt->fs,
                                  shcxt->current_rev,
                                  shcxt->pool));

   /* final sanity check:  after switching to the new revision, make
      sure the CWD still exists!  If not, keep cd'ing upwards until you
      find a parent that exists, even if it means going back to the
      root directory. */
   SVN_ERR (path_stat (&exists, shcxt->cwd, shcxt, pool));
   while (exists == FALSE)
     {
       svn_path_remove_component (shcxt->cwd);
       /* again, broken path library */
       if (svn_stringbuf_isempty (shcxt->cwd))
         svn_stringbuf_appendcstr (shcxt->cwd, "/");

       SVN_ERR (path_stat (&exists, shcxt->cwd, shcxt, pool));
     }

   /* ### if we bumped the user upwards, should we mention it? */

   return SVN_NO_ERROR;
 }


 /* Helper:  print a single dirent nicely. */
 static svn_error_t *
 print_dirent (svn_stringbuf_t *abs_path,
               svn_fs_dirent_t *entry,
               shcxt_t *shcxt,
               apr_pool_t *pool)
 {
   int is_dir;
   apr_off_t size;
   svn_revnum_t created_rev;
   svn_stringbuf_t *id_str;
   svn_boolean_t has_props;

   apr_hash_t *props;

   /* directory or file? */
   SVN_ERR (svn_fs_is_dir (&is_dir, shcxt->root, abs_path->data, pool));

   /* calculate size of dirent */
   if (is_dir)
     size = 0;
   else
     SVN_ERR (svn_fs_file_length (&size, shcxt->root, abs_path->data, pool));

   /* revision in which this file was created. */
   SVN_ERR (svn_fs_node_created_rev (&created_rev,
                                     shcxt->root, abs_path->data, pool));

   /* convert id to a stringbuf */
   id_str = svn_fs_unparse_id (entry->id, pool);

   /* does this object have properties?
      funny, there's no way to know but to see if we fetch a non-empty
      prophash. */
   SVN_ERR (svn_fs_node_proplist (&props, shcxt->root, abs_path->data, pool));
   if (apr_hash_count (props) != 0)
     has_props = TRUE;
   else
     has_props = FALSE;


   /* Now PRINT all this information. */
   printf ("  <%8s>  [%6ld]  %1d  %10ld",
           id_str->data, created_rev, has_props, (long int) size);
   printf ("    %s", entry->name);
   if (is_dir)
     printf ("/");
   printf ("\n");

   return SVN_NO_ERROR;
 }


 /* List files in CWD, or possibly at relative/absolute PATH.  */
 static svn_error_t *
 ls (shcxt_t *shcxt,
     char *path,
     apr_pool_t *pool)
 {
   svn_stringbuf_t *tmp_path;
   apr_hash_t *dirents;
   apr_hash_index_t *hi;

   /* default */
   svn_stringbuf_t *path_to_list = shcxt->cwd;

   if (strlen(path) != 0)
     {
       /* we want to list some dir -other- than CWD */
       svn_stringbuf_t *new_path;

       SVN_ERR (compute_new_path (&new_path, shcxt->cwd, path,
                                  shcxt, pool));

       if (new_path == NULL)
         {
           /* non-fatal error */
           printf ("No such object: %s\n", path);
           return SVN_NO_ERROR;
         }
       else
         path_to_list = new_path;
     }

   SVN_ERR (svn_fs_dir_entries (&dirents, shcxt->root,
                                path_to_list->data, pool));
   tmp_path = svn_stringbuf_dup (path_to_list, pool);

   for (hi = apr_hash_first (pool, dirents); hi; hi = apr_hash_next (hi))
     {
       const void *key;
       void *val;
       const char *entryname;
       svn_fs_dirent_t *entry;

       apr_hash_this (hi, &key, NULL, &val);
       entryname = (const char *) key;
       entry = (svn_fs_dirent_t *) val;
       svn_path_add_component_nts (tmp_path, entry->name);

       SVN_ERR (print_dirent (tmp_path, entry, shcxt, pool));

       svn_path_remove_component (tmp_path);
     }

   fflush (stdout);

   return SVN_NO_ERROR;
 }


 /* ----------------------------------------------------------------*/
 /** Main routines **/

 /* Print the SHCXT info in a prompt. */
 static void
 display_prompt (shcxt_t *shcxt)
 {
   /* this could be more sophisticated, or configurable, I suppose. */

   printf ("<%ld: %s>$ ", (long int) shcxt->current_rev, shcxt->cwd->data);
   fflush (stdout);
 }


 /* Read stdin into a new stringbuf_t allocated in POOL; input is
    terminated when user types a newline.  Assign stringbuf to
    *INPUT. */
 static svn_error_t *
 get_input (svn_stringbuf_t **input,
            apr_pool_t *pool)
 {
   apr_status_t status;
   apr_file_t *fp;
   char c;
   svn_stringbuf_t *strbuf = svn_stringbuf_create ("", pool);

   status = apr_file_open_stdin (&fp, pool);
   if (status)
     return
       svn_error_create (status, 0, NULL, pool,
                         "get_input():  couldn't open STDIN.");

   /* ### Rewrite, to make backspaces work??? */

   while (1)
     {
       status = apr_file_getc (&c, fp);
       if (status && (status != APR_EOF))
         return svn_error_create (status, 0, NULL, pool,
                                  "get_input(): error reading STDIN.");
       if ((c == '\n') || (c == '\r'))
         break;

       svn_stringbuf_appendbytes (strbuf, &c, 1);
     }

   *input = strbuf;
   return SVN_NO_ERROR;
 }


 /* Parse the user's INPUT string, and call some other routine
    appropriately.  This routine will use POOL and SHCXT to do work.

    If FINISHED is set to non-zero, then the user wants to exit the shell.
  */
 static svn_error_t *
 parse_input (int *finished,
              char *input,
              shcxt_t *shcxt,
              apr_pool_t *pool)
 {
   char *subcommand;
   char *state;

   /* Get the subcommand by grabbing the first "token" of input. */
   subcommand = apr_strtok (input, " ", &state);

   if (subcommand == NULL)
     return SVN_NO_ERROR;

   else if (! strcmp(subcommand, "cd"))
     return cd (state, shcxt, pool);

   else if (! strcmp(subcommand, "cr"))
     return cr (SVN_STR_TO_REV(state), shcxt, pool);

   else if (! strcmp(subcommand, "ls"))
     return ls (shcxt, state, pool);

   else if (! strcmp(subcommand, "help"))
     {
       help();
       return SVN_NO_ERROR;
     }

   else if ((! strcmp(subcommand, "quit"))
            || (! strcmp(subcommand, "exit")))
     *finished = 1;


   return SVN_NO_ERROR;
 }


 /* Main Func, called by main()'s subcommand. */
 svn_error_t *
 svnadmin_run_shell (svn_fs_t *fs, apr_pool_t *pool)
 {
   int finished = 0;

   /* create a shell-context object in the top pool.
      start at the HEAD revision, root directory. */
   shcxt_t *shcxt = apr_pcalloc (pool, sizeof(*shcxt));
   shcxt->fs = fs;
   shcxt->pool = pool;
   shcxt->cwd = svn_stringbuf_create ("/", pool);
   SVN_ERR (cr (SVN_INVALID_REVNUM, shcxt, pool));

   printf ("\n");

   while (! finished)
     {
       /* make a subpool for parsing the next user command. */
       apr_pool_t *subpool = svn_pool_create (pool);
       svn_stringbuf_t *input;

       /* display a prompt. */
       display_prompt (shcxt);

       /* get input from user. */
       SVN_ERR (get_input (&input, subpool));

       /* parse input */
       SVN_ERR (parse_input (&finished, input->data, shcxt, subpool));

       /* lather, rinse, repeat. */
       svn_pool_destroy (subpool);
     }

   printf ("\n");
   return SVN_NO_ERROR;
 }


 /*
  * local variables:
  * eval: (load-file "../../tools/dev/svn-dev.el")
  * end:
  */
	/*
	* shell.c: interactive fs shell for 'svnadmin'
	*
	* ====================================================================
	* Copyright (c) 2000-2002 CollabNet. All rights reserved.
	*
	* This software is licensed as described in the file COPYING, which
	* you should have received as part of this distribution. The terms
	* are also available at http://subversion.tigris.org/license-1.html.
	* If newer versions of this license are posted there, you may use a
	* newer version instead, at your option.
	*
	* This software consists of voluntary contributions made by many
	* individuals. For exact contribution history, see the revision
	* history and logs, available at http://subversion.tigris.org/.
	* ====================================================================
	*/


	#include "svnadmin.h"


	/* Code */

	/* Helper */
	static svn_error_t *
	path_stat (svn_boolean_t *exists,
	svn_stringbuf_t *path,
	shcxt_t *shcxt,
	apr_pool_t *pool)
	{
	apr_hash_t *dirents;
	svn_stringbuf_t parent, basename;
	svn_error_t *err;

	/* Sanity check: does path actually exist?? ### oddly, there is no
	'svn_fs_stat', so they only way we can check is by opening its
	-parent- and doing a hash lookup! */

	svn_path_split (path, &parent, &basename, pool);

	err = svn_fs_dir_entries (&dirents, shcxt->root, parent->data, pool);
	if (err)
	{
	*exists = FALSE;
	return SVN_NO_ERROR;
	}

	/* else... */

	if ((apr_hash_get (dirents, basename->data, basename->len))
	\|\| (! strcmp (path->data, "/")))
	*exists = TRUE;
	else
	*exists = FALSE;

	return SVN_NO_ERROR;
	}



	/* Helper: Given a CURRENT_PATH in a SHCXT, and some GIVEN_PATH that
	is either relative to CURRENT_PATH (or absolute), return a
	*NEW_PATH allocated in POOL that is possibly a combination of the
	two.

	Do a sanity check: if the *NEW_PATH dosen't actually exist in the
	current filesytem revision, then set it to NULL! */
	static svn_error_t *
	compute_new_path (svn_stringbuf_t **new_path,
	svn_stringbuf_t *current_path,
	char *given_path,
	shcxt_t *shcxt,
	apr_pool_t *pool)
	{
	svn_boolean_t exists;
	svn_stringbuf_t *final_path = svn_stringbuf_dup (current_path, pool);

	if (given_path[0] == '/')
	{
	/* if absolute path, just set final_path to it. */
	svn_stringbuf_setempty (final_path);
	svn_stringbuf_appendcstr (final_path, given_path);
	}
	else if (! strcmp (given_path, ".."))
	{
	/* go up a level */
	svn_path_remove_component (final_path);

	/* our path library is so broken, sigh. */
	if (svn_stringbuf_isempty (final_path))
	svn_stringbuf_appendcstr (final_path, "/");
	}
	else
	{
	/* just append path to cwd */
	svn_path_add_component_nts (final_path, given_path);
	}

	SVN_ERR (path_stat (&exists, final_path, shcxt, pool));
	if (exists)
	*new_path = final_path;
	else
	*new_path = NULL;

	return SVN_NO_ERROR;
	}




	/* ----------------------------------------------------------------*/
	/ Subcommands /


	static void
	help (void)
	{
	/* make this not suck. maybe define shell commands in a list
	somewhere, the way it's done with the svn client app. */
	printf ("\nAvailable commands are:\n");

	printf (" cd: change directory\n");
	printf (" cr: change revision\n");
	printf (" ls: list directory entries\n");
	printf (" exit: leave this shell\n");
	}


	/* Change Directory */
	static svn_error_t *
	cd (char *path,
	shcxt_t *shcxt,
	apr_pool_t *pool)
	{
	if (strlen(path) == 0)
	{
	/* no argument? change to root dir. */
	svn_stringbuf_setempty (shcxt->cwd);
	svn_stringbuf_appendcstr (shcxt->cwd, "/");
	}
	else
	{
	svn_stringbuf_t *new_path;

	SVN_ERR (compute_new_path (&new_path, shcxt->cwd, path,
	shcxt, shcxt->pool));

	if (new_path == NULL)
	printf ("No such object: %s\n", path);
	else
	shcxt->cwd = new_path;
	}

	return SVN_NO_ERROR;
	}



	/* Change Revision; INVALID revnum means "change to head revision". */
	static svn_error_t *
	cr (svn_revnum_t rev,
	shcxt_t *shcxt,
	apr_pool_t *pool)
	{
	svn_revnum_t youngest;
	svn_boolean_t exists = FALSE;

	SVN_ERR (svn_fs_youngest_rev (&youngest, shcxt->fs, pool));

	if (! SVN_IS_VALID_REVNUM(rev))
	rev = youngest;

	/* sanity check */
	if ((rev < 0) \|\| (rev > youngest))
	{
	/* non-fatal error */
	printf ("There is no revision %ld.\n", (long int) rev);
	return SVN_NO_ERROR;
	}

	/* else... */

	/* close the old root */
	if (shcxt->root != NULL)
	svn_fs_close_root (shcxt->root);

	/* and open the new root */
	shcxt->current_rev = rev;
	SVN_ERR (svn_fs_revision_root (&(shcxt->root),
	shcxt->fs,
	shcxt->current_rev,
	shcxt->pool));

	/* final sanity check: after switching to the new revision, make
	sure the CWD still exists! If not, keep cd'ing upwards until you
	find a parent that exists, even if it means going back to the
	root directory. */
	SVN_ERR (path_stat (&exists, shcxt->cwd, shcxt, pool));
	while (exists == FALSE)
	{
	svn_path_remove_component (shcxt->cwd);
	/* again, broken path library */
	if (svn_stringbuf_isempty (shcxt->cwd))
	svn_stringbuf_appendcstr (shcxt->cwd, "/");

	SVN_ERR (path_stat (&exists, shcxt->cwd, shcxt, pool));
	}

	/* ### if we bumped the user upwards, should we mention it? */

	return SVN_NO_ERROR;
	}


	/* Helper: print a single dirent nicely. */
	static svn_error_t *
	print_dirent (svn_stringbuf_t *abs_path,
	svn_fs_dirent_t *entry,
	shcxt_t *shcxt,
	apr_pool_t *pool)
	{
	int is_dir;
	apr_off_t size;
	svn_revnum_t created_rev;
	svn_stringbuf_t *id_str;
	svn_boolean_t has_props;

	apr_hash_t *props;

	/* directory or file? */
	SVN_ERR (svn_fs_is_dir (&is_dir, shcxt->root, abs_path->data, pool));

	/* calculate size of dirent */
	if (is_dir)
	size = 0;
	else
	SVN_ERR (svn_fs_file_length (&size, shcxt->root, abs_path->data, pool));

	/* revision in which this file was created. */
	SVN_ERR (svn_fs_node_created_rev (&created_rev,
	shcxt->root, abs_path->data, pool));

	/* convert id to a stringbuf */
	id_str = svn_fs_unparse_id (entry->id, pool);

	/* does this object have properties?
	funny, there's no way to know but to see if we fetch a non-empty
	prophash. */
	SVN_ERR (svn_fs_node_proplist (&props, shcxt->root, abs_path->data, pool));
	if (apr_hash_count (props) != 0)
	has_props = TRUE;
	else
	has_props = FALSE;


	/* Now PRINT all this information. */
	printf (" <%8s> [%6ld] %1d %10ld",
	id_str->data, created_rev, has_props, (long int) size);
	printf (" %s", entry->name);
	if (is_dir)
	printf ("/");
	printf ("\n");

	return SVN_NO_ERROR;
	}


	/* List files in CWD, or possibly at relative/absolute PATH. */
	static svn_error_t *
	ls (shcxt_t *shcxt,
	char *path,
	apr_pool_t *pool)
	{
	svn_stringbuf_t *tmp_path;
	apr_hash_t *dirents;
	apr_hash_index_t *hi;

	/* default */
	svn_stringbuf_t *path_to_list = shcxt->cwd;

	if (strlen(path) != 0)
	{
	/* we want to list some dir -other- than CWD */
	svn_stringbuf_t *new_path;

	SVN_ERR (compute_new_path (&new_path, shcxt->cwd, path,
	shcxt, pool));

	if (new_path == NULL)
	{
	/* non-fatal error */
	printf ("No such object: %s\n", path);
	return SVN_NO_ERROR;
	}
	else
	path_to_list = new_path;
	}

	SVN_ERR (svn_fs_dir_entries (&dirents, shcxt->root,
	path_to_list->data, pool));
	tmp_path = svn_stringbuf_dup (path_to_list, pool);

	for (hi = apr_hash_first (pool, dirents); hi; hi = apr_hash_next (hi))
	{
	const void *key;
	void *val;
	const char *entryname;
	svn_fs_dirent_t *entry;

	apr_hash_this (hi, &key, NULL, &val);
	entryname = (const char *) key;
	entry = (svn_fs_dirent_t *) val;
	svn_path_add_component_nts (tmp_path, entry->name);

	SVN_ERR (print_dirent (tmp_path, entry, shcxt, pool));

	svn_path_remove_component (tmp_path);
	}

	fflush (stdout);

	return SVN_NO_ERROR;
	}


	/* ----------------------------------------------------------------*/
	/ Main routines /

	/* Print the SHCXT info in a prompt. */
	static void
	display_prompt (shcxt_t *shcxt)
	{
	/* this could be more sophisticated, or configurable, I suppose. */

	printf ("<%ld: %s>$ ", (long int) shcxt->current_rev, shcxt->cwd->data);
	fflush (stdout);
	}



	/* Read stdin into a new stringbuf_t allocated in POOL; input is
	terminated when user types a newline. Assign stringbuf to
	INPUT. /
	static svn_error_t *
	get_input (svn_stringbuf_t **input,
	apr_pool_t *pool)
	{
	apr_status_t status;
	apr_file_t *fp;
	char c;
	svn_stringbuf_t *strbuf = svn_stringbuf_create ("", pool);

	status = apr_file_open_stdin (&fp, pool);
	if (status)
	return
	svn_error_create (status, 0, NULL, pool,
	"get_input(): couldn't open STDIN.");

	/* ### Rewrite, to make backspaces work??? */

	while (1)
	{
	status = apr_file_getc (&c, fp);
	if (status && (status != APR_EOF))
	return svn_error_create (status, 0, NULL, pool,
	"get_input(): error reading STDIN.");
	if ((c == '\n') \|\| (c == '\r'))
	break;

	svn_stringbuf_appendbytes (strbuf, &c, 1);
	}

	*input = strbuf;
	return SVN_NO_ERROR;
	}



	/* Parse the user's INPUT string, and call some other routine
	appropriately. This routine will use POOL and SHCXT to do work.

	If FINISHED is set to non-zero, then the user wants to exit the shell.
	*/
	static svn_error_t *
	parse_input (int *finished,
	char *input,
	shcxt_t *shcxt,
	apr_pool_t *pool)
	{
	char *subcommand;
	char *state;

	/* Get the subcommand by grabbing the first "token" of input. */
	subcommand = apr_strtok (input, " ", &state);

	if (subcommand == NULL)
	return SVN_NO_ERROR;

	else if (! strcmp(subcommand, "cd"))
	return cd (state, shcxt, pool);

	else if (! strcmp(subcommand, "cr"))
	return cr (SVN_STR_TO_REV(state), shcxt, pool);

	else if (! strcmp(subcommand, "ls"))
	return ls (shcxt, state, pool);

	else if (! strcmp(subcommand, "help"))
	{
	help();
	return SVN_NO_ERROR;
	}

	else if ((! strcmp(subcommand, "quit"))
	\|\| (! strcmp(subcommand, "exit")))
	*finished = 1;


	return SVN_NO_ERROR;
	}



	/* Main Func, called by main()'s subcommand. */
	svn_error_t *
	svnadmin_run_shell (svn_fs_t fs, apr_pool_t pool)
	{
	int finished = 0;

	/* create a shell-context object in the top pool.
	start at the HEAD revision, root directory. */
	shcxt_t shcxt = apr_pcalloc (pool, sizeof(shcxt));
	shcxt->fs = fs;
	shcxt->pool = pool;
	shcxt->cwd = svn_stringbuf_create ("/", pool);
	SVN_ERR (cr (SVN_INVALID_REVNUM, shcxt, pool));

	printf ("\n");

	while (! finished)
	{
	/* make a subpool for parsing the next user command. */
	apr_pool_t *subpool = svn_pool_create (pool);
	svn_stringbuf_t *input;

	/* display a prompt. */
	display_prompt (shcxt);

	/* get input from user. */
	SVN_ERR (get_input (&input, subpool));

	/* parse input */
	SVN_ERR (parse_input (&finished, input->data, shcxt, subpool));

	/* lather, rinse, repeat. */
	svn_pool_destroy (subpool);
	}

	printf ("\n");
	return SVN_NO_ERROR;
	}





	/*
	* local variables:
	* eval: (load-file "../../tools/dev/svn-dev.el")
	* end:
	*/