fltk/src/Fl_Menu_add.cxx

//
// "$Id$"
//
// Menu utilities for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2008 by Bill Spitzak and others.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
// USA.
//
// Please report all bugs and problems on the following page:
//
//     http://www.fltk.org/str.php
//
// Methods to alter the menu in an Fl_Menu_ widget.

// These are for Forms emulation and for dynamically changing the
// menus.  They are in this source file so they are not linked in if
// not used, which is what will happen if the the program only uses
// constant menu tables.

// Not at all guaranteed to be Forms compatable, especially with any
// string with a % sign in it!

#include <FL/Fl_Menu_.H>
#include "flstring.h"
#include <stdio.h>
#include <stdlib.h>

// If the array is this, we will double-reallocate as necessary:
static Fl_Menu_Item* local_array = 0;
static int local_array_alloc = 0; // number allocated
static int local_array_size = 0; // == size(local_array)
extern Fl_Menu_* fl_menu_array_owner; // in Fl_Menu_.cxx

// For historical reasons there are matching methods that work on a
// user-allocated array of Fl_Menu_Item.  These methods are quite
// depreciated and should not be used.  These old methods use the
// above pointers to detect if the array belongs to an Fl_Menu_
// widget, and if so it reallocates as necessary.

// Insert a single Fl_Menu_Item into an array of size at offset n,
// if this is local_array it will be reallocated if needed.
static Fl_Menu_Item* insert(
  Fl_Menu_Item* array, int size,
  int n,
  const char *text,
  int flags
) {
  if (array == local_array && size >= local_array_alloc) {
    local_array_alloc = 2*size;
    Fl_Menu_Item* newarray = new Fl_Menu_Item[local_array_alloc];
    memmove(newarray, array, size*sizeof(Fl_Menu_Item));
    delete[] local_array;
    local_array = array = newarray;
  }
  // move all the later items:
  memmove(array+n+1, array+n, sizeof(Fl_Menu_Item)*(size-n));
  // create the new item:
  Fl_Menu_Item* m = array+n;
  m->text = text ? strdup(text) : 0;
  m->shortcut_ = 0;
  m->callback_ = 0;
  m->user_data_ = 0;
  m->flags = flags;
  m->labeltype_ = m->labelsize_ = m->labelcolor_ = 0;
  m->labelfont_ = FL_HELVETICA; 
  return array;
}

// Comparison that does not care about deleted '&' signs:
static int compare(const char* a, const char* b) {
  for (;;) {
    int n = *a-*b;
    if (n) {
      if (*a == '&') a++;
      else if (*b == '&') b++;
      else return n;
    } else if (*a) {
      a++; b++;
    } else {
      return 0;
    }
  }
}

/** Adds an item.  The text is split at '/' characters to automatically
   produce submenus (actually a totally unnecessary feature as you can
   now add submenu titles directly by setting SUBMENU in the flags):
*/
int Fl_Menu_Item::add(
  const char *mytext,
  int sc,
  Fl_Callback *cb,	
  void *data,
  int myflags
) {
  Fl_Menu_Item *array = this;
  Fl_Menu_Item *m = this;
  const char *p;
  char *q;
  char buf[1024];

  int msize = array==local_array ? local_array_size : array->size();
  int flags1 = 0;
  const char* item;

  // split at slashes to make submenus:
  for (;;) {

    // leading slash makes us assumme it is a filename:
    if (*mytext == '/') {item = mytext; break;}

    // leading underscore causes divider line:
    if (*mytext == '_') {mytext++; flags1 = FL_MENU_DIVIDER;}

    // copy to buf, changing \x to x:
    q = buf;
    for (p=mytext; *p && *p != '/'; *q++ = *p++) if (*p=='\\' && p[1]) p++;
    *q = 0;

    item = buf;
    if (*p != '/') break; /* not a menu title */
    mytext = p+1;	/* point at item title */

    /* find a matching menu title: */
    for (; m->text; m = m->next())
      if (m->flags&FL_SUBMENU && !compare(item, m->text)) break;

    if (!m->text) { /* create a new menu */
      int n = m-array;
      array = insert(array, msize, n, item, FL_SUBMENU|flags1);
      msize++;
      array = insert(array, msize, n+1, 0, 0);
      msize++;
      m = array+n;
    }
    m++;	/* go into the submenu */
    flags1 = 0;
  }

  /* find a matching menu item: */
  for (; m->text; m = m->next())
    if (!(m->flags&FL_SUBMENU) && !compare(m->text,item)) break;

  if (!m->text) {	/* add a new menu item */
    int n = m-array;
    array = insert(array, msize, n, item, myflags|flags1);
    msize++;
    if (myflags & FL_SUBMENU) { // add submenu delimiter
      array = insert(array, msize, n+1, 0, 0);
      msize++;
    }
    m = array+n;
  }

  /* fill it in */
  m->shortcut_ = sc;
  m->callback_ = cb;
  m->user_data_ = data;
  m->flags = myflags|flags1;

  if (array == local_array) local_array_size = msize;
  return m-array;
}

/**
  Adds a new menu item, with a title string,  shortcut int (or string), 
  callback, argument to the  callback, and flags.  
  If the menu array was directly set with menu(x) then copy() is done 
  to make a private array.
  
  <p>The characters "&", "/", "\", and "_" are treated as
  special characters in the label string. The "&" character
  specifies that the following character is an accelerator and
  will be underlined. The "\" character is used to escape the next
  character in the string. Labels starting with the "_" character
  cause a divider to be placed after that menu item.</p>
  
  <p>A label of the form "foo/bar/baz" will create a
  submenus called "foo" and "bar" with an
  entry called "baz". The "/" character is ignored if it
  appears as the first character of the label string, e.g.
  "/foo/bar/baz".</p>
  
  <p>The label string is copied to new memory and can be freed.
  The other arguments (including the shortcut) are copied into the
  menu item unchanged. </P>
  
  <P>If an item exists already with that name then it is replaced with
  this new one.  Otherwise this new one is added to the end of the
  correct menu or submenu.  The return value is the offset into the array
  that the new entry was placed at.</P>
  
  <P>Shortcut can be 0L, or either a modifier/key combination (for example
  FL_CTRL+'A') or a string describing the shortcut in one of two ways:</p>
  
  \code
   [#+^]&lt;ascii_value&gt;<3B>   eg. "97", "^97", "+97", "#97"
   [#+^]&lt;ascii_char&gt;<3B>    eg. "a", "^a", "+a", "#a"
  \endcode
  ..where &lt;ascii_value&gt; is a decimal value representing an
  ascii character (eg. 97 is the ascii for 'a'), and the optional
  prefixes enhance the value  that follows. Multiple prefixes must
  appear in the above order.
  \code
   # - Alt
   + - Shift
   ^ - Control
  \endcode
  Text shortcuts are converted to integer shortcut by calling 
  int fl_old_shortcut(const char*).
  
  <P>The return value is the index into the array that the entry was put. </P>
  
  <P>No items must be added to a menu during a callback to the same menu.</P>
  
  
 */
int Fl_Menu_::add(const char *t, int s, Fl_Callback *c,void *v,int f) {
  // make this widget own the local array:
  if (this != fl_menu_array_owner) {
    if (fl_menu_array_owner) {
      Fl_Menu_* o = fl_menu_array_owner;
      // the previous owner get's its own correctly-sized array:
      int value_offset = o->value_-local_array;
      int n = local_array_size;
      Fl_Menu_Item* newMenu = o->menu_ = new Fl_Menu_Item[n];
      memcpy(newMenu, local_array, n*sizeof(Fl_Menu_Item));
      if (o->value_) o->value_ = newMenu+value_offset;
    }
    if (menu_) {
      // this already has a menu array, use it as the local one:
      delete[] local_array;
      if (!alloc) copy(menu_); // duplicate a user-provided static array
      // add to the menu's current array:
      local_array_alloc = local_array_size = size();
      local_array = menu_;
    } else {
      // start with a blank array:
      alloc = 2; // indicates that the strings can be freed
      if (local_array) {
	menu_ = local_array;
      } else {
	local_array_alloc = 15;
	local_array = menu_ = new Fl_Menu_Item[local_array_alloc];
        memset(local_array, 0, sizeof(Fl_Menu_Item) * local_array_alloc);
      }
      memset(menu_, 0, sizeof(Fl_Menu_Item));
      local_array_size = 1;
    }
    fl_menu_array_owner = this;
  }
  int r = menu_->add(t,s,c,v,f);
  // if it rellocated array we must fix the pointer:
  int value_offset = value_-menu_;
  menu_ = local_array; // in case it reallocated it
  if (value_) value_ = menu_+value_offset;
  return r;
}

/**
  This is a Forms (and SGI GL library) compatible add function, it
  adds many menu items, with '|' seperating the menu items, and tab
  separating the menu item names from an optional shortcut string.

  The passed string is split at any '|' characters and then
  add(s,0,0,0,0) is done with each section. This is
  often useful if you are just using the value, and is compatible
  with Forms and other GL programs. The section strings use the
  same special characters as described for the long version of add()</p>
  
  <P>No items must be added to a menu during a callback to the same menu.
*/
int Fl_Menu_::add(const char *str) {
  char buf[1024];
  int r = 0;
  while (*str) {
    int sc = 0;
    char *c;
    for (c = buf; c < (buf + sizeof(buf) - 2) && *str && *str != '|'; str++) {
      if (*str == '\t') {*c++ = 0; sc = fl_old_shortcut(str);}
      else *c++ = *str;
    }
    *c = 0;
    r = add(buf, sc, 0, 0, 0);
    if (*str) str++;
  }
  return r;
}

/**
  Changes the text of item n.  This is the only way to get
  slash into an add()'ed menu item.  If the menu array was directly set
  with menu(x) then copy() is done to make a private array.
*/
void Fl_Menu_::replace(int i, const char *str) {
  if (i<0 || i>=size()) return;
  if (!alloc) copy(menu_);
  if (alloc > 1) {
    free((void *)menu_[i].text);
    str = strdup(str);
  }
  menu_[i].text = str;
}
/**
  Deletes item n from the menu.  If the menu array was directly
  set with menu(x) then copy() is done to make a private array.
  
  <P>No items must be removed from a menu during a callback to the same menu.
*/
void Fl_Menu_::remove(int i) {
  int n = size();
  if (i<0 || i>=n) return;
  if (!alloc) copy(menu_);
  // find the next item, skipping submenus:
  Fl_Menu_Item* item = menu_+i;
  const Fl_Menu_Item* next_item = item->next();
  // delete the text only if all items were created with add():
  if (alloc > 1) {
    for (Fl_Menu_Item* m = item; m < next_item; m++)
      if (m->text) free((void*)(m->text));
  }
  // MRS: "n" is the menu size(), which includes the trailing NULL entry...
  memmove(item, next_item, (menu_+n-next_item)*sizeof(Fl_Menu_Item));
}

//
// End of "$Id$".
//