haracters as a single space. */
  svn_diff_file_ignore_space_change,

  /** Ignore all whitespace characters. */
  svn_diff_file_ignore_space_all
} svn_diff_file_ignore_space_t;

/** Options to control the behaviour of the file diff routines.
 *
 * @since New in 1.4.
 *
 * @note This structure may be extended in the future, so to preserve binary
 * compatibility, users must not allocate structs of this type themselves.
 * @see svn_diff_file_options_create().
 *
 * @note Although its name suggests otherwise, this structure is used to
 *       pass options to file as well as in-memory diff functions.
 */
typedef struct svn_diff_file_options_t
{
  /** To what extent whitespace should be ignored when comparing lines.
   * The default is @c svn_diff_file_ignore_space_none. */
  svn_diff_file_ignore_space_t ignore_space;
  /** Whether to treat all end-of-line markers the same when comparing lines.
   * The default is @c FALSE. */
  svn_boolean_t ignore_eol_style;
  /** Whether the "@@" lines of the unified diff output should include a prefix
    * of the nearest preceding line that starts with a character that might be
    * the initial character of a C language identifier.  The default is
    * @c FALSE.
    * @since New in 1.5.
    */
  svn_boolean_t show_c_function;

  /** The number of context lines produced above and below modifications, if
   * available. The number of context lines must be >= 0.
   *
   * @since New in 1.9 */
  int context_size;
} svn_diff_file_options_t;

/** Allocate a @c svn_diff_file_options_t structure in @a pool, initializing
 * it with default values.
 *
 * @since New in 1.4.
 */
svn_diff_file_options_t *
svn_diff_file_options_create(apr_pool_t *pool);

/**
 * Parse @a args, an array of <tt>const char *</tt> command line switches
 * and adjust @a options accordingly.  @a options is assumed to be initialized
 * with default values.  @a pool is used for temporary allocation.
 *
 * @since New in 1.4.
 *
 * The following options are supported:
 * - --ignore-space-change, -b
 * - --ignore-all-space, -w
 * - --ignore-eol-style
 * - --show-c-function, -p @since New in 1.5.
 * - --context, -U ARG @since New in 1.9.
 * - --unified, -u (for compatibility, does nothing).
 */
svn_error_t *
svn_diff_file_options_parse(svn_diff_file_options_t *options,
                            const apr_array_header_t *args,
                            apr_pool_t *pool);