Add minimal version of class Fl_String

This class will be used in fl_input_str() and fl_password_str(). Todo: add missing documentation ...
2026-05-31 05:35:29 +08:00 · 2021-12-04 12:28:42 +01:00
parent 0f72957a24
commit 2404656266
4 changed files with 275 additions and 0 deletions
@@ -0,0 +1,114 @@
+//
+// Basic Fl_String header for the Fast Light Tool Kit (FLTK).
+//
+// Copyright 2021 by Bill Spitzak and others.
+//
+// This library is free software. Distribution and use rights are outlined in
+// the file "COPYING" which should have been included with this file.  If this
+// file is missing or damaged, see the license at:
+//
+//     https://www.fltk.org/COPYING.php
+//
+// Please see the following page on how to report bugs and issues:
+//
+//     https://www.fltk.org/bugs.php
+//
+
+#ifndef _FL_FL_STRING_H_
+#define _FL_FL_STRING_H_
+
+/** \file FL/Fl_String.H
+  Basic Fl_String class for FLTK.
+*/
+
+/**
+  Fl_String is the basic string class for FLTK.
+
+  In this version Fl_String can be used to store strings, copy strings,
+  and move strings. There are no string manipulation methods yet.
+
+  Fl_String can hold the value of an Fl_Input widget including \e nul bytes
+  if the constructor Fl_String(const char *str, int size) is used.
+
+  Assignment and copy constructors \b copy the string value such that the
+  source string can be freed immediately after the assignment.
+
+  The string value() can be an empty string \c "" or \c NULL.
+
+  If value() is not \c NULL it is guaranteed that the string is terminated by
+  a trailing \c nul byte even if the string contains embedded \c nul bytes.
+
+  The method size() returns the full string size, whether the string contains
+  embedded \c nul bytes or not. The special method slen() returns 0 if value()
+  is \c NULL, otherwise the same as \c strlen() would do.
+
+  Examples:
+  \code
+  Fl_String np(NULL);
+  printf("  np    : value = %p, size = %d, slen = %d\n", np.value(), np.size(), np.slen());
+  Fl_String empty("");
+  printf("  empty : value = %p, size = %d\n", empty.value(), empty.size());
+  Fl_String fltk("FLTK");
+  Fl_Input i(0, 0, 0, 0);
+  i.value("abc\0def", 7);
+  Fl_String str(i.value(), i.size());
+  printf("  str   : strlen = %lu, size = %d, capacity = %d\n",
+         strlen(str.value()), str.size(), str.capacity());
+
+  Output:
+
+  np    : value = (nil), size = 0, slen = 0
+  empty : value = 0x562840befbf0, size = 0
+  str   : strlen = 3, size = 7, capacity = 15
+  \endcode
+
+  \since 1.4.0
+
+  \todo Complete documentation of class Fl_String
+*/
+
+class Fl_String {
+private:
+  int size_;
+  char *value_;
+  int capacity_;
+
+public:
+  Fl_String();
+  Fl_String(const char *str);
+  Fl_String(const char *str, int size);
+
+  // copy constructor
+  Fl_String(const Fl_String &in);
+
+  // copy assignment operator
+  Fl_String& operator=(const Fl_String &in);
+
+  // assignment operator for 'const char *'
+  Fl_String& operator=(const char *in);
+
+  virtual ~Fl_String();
+
+private:
+  void init();
+  void alloc_buf(int size);
+  void release();
+
+public:
+  void value(const char *str);
+  void value(const char *str, int slen);
+
+  const char *value() const { return value_; }
+  int size() const { return size_; }
+
+  int slen() const;
+  int capacity() const;
+
+  // ==================================  DEBUG  ==================================
+
+  void debug(const char *info) const;           // output string info
+  void hexdump(const char *info) const;         // output info + hexdump
+
+}; // class Fl_String
+
+#endif // _FL_FL_STRING_H_