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diff --git a/documentation/editor.html b/documentation/editor.html deleted file mode 100644 index c2dc39ad3..000000000 --- a/documentation/editor.html +++ /dev/null @@ -1,911 +0,0 @@ -<HTML> -<HEAD> - <TITLE>4 - Designing a Simple Text Editor</TITLE> -</HEAD> -<BODY> - -<H1 ALIGN="RIGHT"><A NAME="editor">4 - Designing a Simple Text Editor</A></H1> - -<P>This chapter takes you through the design of a simple -FLTK-based text editor. - -<H2>Determining the Goals of the Text Editor</H2> - -<P>Since this will be the first big project you'll be doing with FLTK, -lets define what we want our text editor to do: - -<OL> - - <LI>Provide a menubar/menus for all functions.</LI> - <LI>Edit a single text file, possibly with multiple views.</LI> - <LI>Load from a file.</LI> - <LI>Save to a file.</LI> - <LI>Cut/copy/delete/paste functions.</LI> - <LI>Search and replace functions.</LI> - <LI>Keep track of when the file has been changed.</LI> - -</OL> - -<!-- NEED 4in --> - -<H2>Designing the Main Window</H2> - -<P>Now that we've outlined the goals for our editor, we can begin with -the design of our GUI. Obviously the first thing that we need is a -window, which we'll place inside a class called <TT>EditorWindow</TT>: - -<UL><PRE> -class EditorWindow : public Fl_Double_Window { - public: - EditorWindow(int w, int h, const char* t); - ~EditorWindow(); - - Fl_Window *replace_dlg; - Fl_Input *replace_find; - Fl_Input *replace_with; - Fl_Button *replace_all; - Fl_Return_Button *replace_next; - Fl_Button *replace_cancel; - - Fl_Text_Editor *editor; - char search[256]; -}; -</PRE></UL> - -<H2>Variables</H2> - -<P>Our text editor will need some global variables to keep track of -things: - -<UL><PRE> -int changed = 0; -char filename[256] = ""; -Fl_Text_Buffer *textbuf; -</PRE></UL> - -<P>The <TT>textbuf</TT> variable is the text editor buffer for -our window class described previously. We'll cover the other -variables as we build the application.</P> - -<H2>Menubars and Menus</H2> - -<P>The first goal requires us to use a menubar and menus that -define each function the editor needs to perform. The <A -href="Fl_Menu_Item.html"><TT>Fl_Menu_Item</TT></A> structure is -used to define the menus and items in a menubar:</P> - -<UL><PRE> -Fl_Menu_Item menuitems[] = { - { "&File", 0, 0, 0, FL_SUBMENU }, - { "&New File", 0, (Fl_Callback *)new_cb }, - { "&Open File...", FL_CTRL + 'o', (Fl_Callback *)open_cb }, - { "&Insert File...", FL_CTRL + 'i', (Fl_Callback *)insert_cb, 0, FL_MENU_DIVIDER }, - { "&Save File", FL_CTRL + 's', (Fl_Callback *)save_cb }, - { "Save File &As...", FL_CTRL + FL_SHIFT + 's', (Fl_Callback *)saveas_cb, 0, FL_MENU_DIVIDER }, - { "New &View", FL_ALT + 'v', (Fl_Callback *)view_cb, 0 }, - { "&Close View", FL_CTRL + 'w', (Fl_Callback *)close_cb, 0, FL_MENU_DIVIDER }, - { "E&xit", FL_CTRL + 'q', (Fl_Callback *)quit_cb, 0 }, - { 0 }, - - { "&Edit", 0, 0, 0, FL_SUBMENU }, - { "&Undo", FL_CTRL + 'z', (Fl_Callback *)undo_cb, 0, FL_MENU_DIVIDER }, - { "Cu&t", FL_CTRL + 'x', (Fl_Callback *)cut_cb }, - { "&Copy", FL_CTRL + 'c', (Fl_Callback *)copy_cb }, - { "&Paste", FL_CTRL + 'v', (Fl_Callback *)paste_cb }, - { "&Delete", 0, (Fl_Callback *)delete_cb }, - { 0 }, - - { "&Search", 0, 0, 0, FL_SUBMENU }, - { "&Find...", FL_CTRL + 'f', (Fl_Callback *)find_cb }, - { "F&ind Again", FL_CTRL + 'g', find2_cb }, - { "&Replace...", FL_CTRL + 'r', replace_cb }, - { "Re&place Again", FL_CTRL + 't', replace2_cb }, - { 0 }, - - { 0 } -}; -</PRE></UL> - -<P>Once we have the menus defined we can create the -<TT>Fl_Menu_Bar</TT> widget and assign the menus to it with:</P> - -<UL><PRE> -Fl_Menu_Bar *m = new Fl_Menu_Bar(0, 0, 640, 30); -m->copy(menuitems); -</PRE></UL> - -<P>We'll define the callback functions later. - -<H2>Editing the Text</H2> - -<P>To keep things simple our text editor will use the -<A HREF="Fl_Text_Editor.html"><TT>Fl_Text_Editor</TT></A> -widget to edit the text: - -<UL><PRE> -w->editor = new Fl_Text_Editor(0, 30, 640, 370); -w->editor->buffer(textbuf); -</PRE></UL> - -<P>So that we can keep track of changes to the file, we also want to add -a "modify" callback:</P> - -<UL><PRE> -textbuf->add_modify_callback(changed_cb, w); -textbuf->call_modify_callbacks(); -</PRE></UL> - -<P>Finally, we want to use a mono-spaced font like <TT>FL_COURIER</TT>: - -<UL><PRE> -w->editor->textfont(FL_COURIER); -</PRE></UL> - -<H2>The Replace Dialog</H2> - -<P>We can use the FLTK convenience functions for many of the -editor's dialogs, however the replace dialog needs its own -custom window. To keep things simple we will have a -"find" string, a "replace" string, and -"replace all", "replace next", and -"cancel" buttons. The strings are just -<TT>Fl_Input</TT> widgets, the "replace all" and -"cancel" buttons are <TT>Fl_Button</TT> widgets, and -the "replace next " button is a -<TT>Fl_Return_Button</TT> widget:</P> - -<P ALIGN="CENTER"><IMG src="editor-replace.gif" ALT="The search and replace dialog."><BR> -<I>Figure 4-1: The search and replace dialog.</I></P> - -<UL><PRE> -Fl_Window *replace_dlg = new Fl_Window(300, 105, "Replace"); -Fl_Input *replace_find = new Fl_Input(70, 10, 200, 25, "Find:"); -Fl_Input *replace_with = new Fl_Input(70, 40, 200, 25, "Replace:"); -Fl_Button *replace_all = new Fl_Button(10, 70, 90, 25, "Replace All"); -Fl_Button *replace_next = new Fl_Button(105, 70, 120, 25, "Replace Next"); -Fl_Button *replace_cancel = new Fl_Button(230, 70, 60, 25, "Cancel"); -</PRE></UL> - -<H2>Callbacks</H2> - -<P>Now that we've defined the GUI components of our editor, we -need to define our callback functions.</P> - -<H3>changed_cb()</H3> - -<P>This function will be called whenever the user changes any text in the -<TT>editor</TT> widget: - -<UL><PRE> -void changed_cb(int, int nInserted, int nDeleted,int, const char*, void* v) { - if ((nInserted || nDeleted) && !loading) changed = 1; - EditorWindow *w = (EditorWindow *)v; - set_title(w); - if (loading) w->editor->show_insert_position(); -} -</PRE></UL> - -<P>The <TT>set_title()</TT> function is one that we will write to set -the changed status on the current file. We're doing it this way -because we want to show the changed status in the window's -title bar. - -<H3>copy_cb()</H3> - -<P>This callback function will call <A -href="Fl_Text_Editor.html#Fl_Text_Editor.kf_copy"><TT>kf_copy()</TT></A> -to copy the currently selected text to the clipboard:</P> - -<UL><PRE> -void copy_cb(Fl_Widget*, void* v) { - EditorWindow* e = (EditorWindow*)v; - Fl_Text_Editor::kf_copy(0, e->editor); -} -</PRE></UL> - -<H3>cut_cb()</H3> - -<P>This callback function will call <A -href="Fl_Text_Editor.html#Fl_Text_Editor.kf_cut"><TT>kf_cut()</TT></A> -to cut the currently selected text to the clipboard:</P> - -<UL><PRE> -void cut_cb(Fl_Widget*, void* v) { - EditorWindow* e = (EditorWindow*)v; - Fl_Text_Editor::kf_cut(0, e->editor); -} -</PRE></UL> - -<H3>delete_cb()</H3> - -<P>This callback function will call <A -href="Fl_Text_Buffer.html#Fl_Text_Buffer.remove_selection"><TT>remove_selection()</TT></A> -to delete the currently selected text to the clipboard:</P> - -<UL><PRE> -void delete_cb(Fl_Widget*, void* v) { - textbuf->remove_selection(); -} -</PRE></UL> - -<H3>find_cb()</H3> - -<P>This callback function asks for a search string using the <A -href="functions.html#fl_input2"><TT>fl_input()</TT></A> -convenience function and then calls the <TT>find2_cb()</TT> -function to find the string: - -<UL><PRE> -void find_cb(Fl_Widget* w, void* v) { - EditorWindow* e = (EditorWindow*)v; - const char *val; - - val = fl_input("Search String:", e->search); - if (val != NULL) { - // User entered a string - go find it! - strcpy(e->search, val); - find2_cb(w, v); - } -</PRE></UL> - -<H3>find2_cb()</H3> - -<P>This function will find the next occurrence of the search -string. If the search string is blank then we want to pop up the -search dialog: - -<UL><PRE> -void find2_cb(Fl_Widget* w, void* v) { - EditorWindow* e = (EditorWindow*)v; - if (e->search[0] == '\0') { - // Search string is blank; get a new one... - find_cb(w, v); - return; - } - - int pos = e->editor->insert_position(); - int found = textbuf->search_forward(pos, e->search, &pos); - if (found) { - // Found a match; select and update the position... - textbuf->select(pos, pos+strlen(e->search)); - e->editor->insert_position(pos+strlen(e->search)); - e->editor->show_insert_position(); - } - else fl_alert("No occurrences of \'%s\' found!", e->search); -} -</PRE></UL> - -<P>If the search string cannot be found we use the <A -href="functions.html#fl_alert"><TT>fl_alert()</TT></A> -convenience function to display a message to that effect. - -<H3>new_cb()</H3> -<P>This callback function will clear the editor widget and current -filename. It also calls the <TT>check_save()</TT> function to give the -user the opportunity to save the current file first as needed: - -<UL><PRE> -void new_cb(Fl_Widget*, void*) { - if (!check_save()) return; - - filename[0] = '\0'; - textbuf->select(0, textbuf->length()); - textbuf->remove_selection(); - changed = 0; - textbuf->call_modify_callbacks(); -} -</PRE></UL> - -<H3>open_cb()</H3> - -<P>This callback function will ask the user for a filename and then load -the specified file into the input widget and current filename. It also -calls the <TT>check_save()</TT> function to give the user the -opportunity to save the current file first as needed: - -<UL><PRE> -void open_cb(Fl_Widget*, void*) { - if (!check_save()) return; - - char *newfile = fl_file_chooser("Open File?", "*", filename); - if (newfile != NULL) load_file(newfile, -1); -} -</PRE></UL> - -<P>We call the <TT>load_file()</TT> function to actually load the file. - -<H3>paste_cb()</H3> - -<P>This callback function will call <A -href="Fl_Text_Editor.html#Fl_Text_Editor.kf_paste"><TT>kf_paste()</TT></A> -to paste the clipboard at the current position:</P> - -<UL><PRE> -void paste_cb(Fl_Widget*, void* v) { - EditorWindow* e = (EditorWindow*)v; - Fl_Text_Editor::kf_paste(0, e->editor); -} -</PRE></UL> - -<H3>quit_cb()</H3> - -<P>The quit callback will first see if the current file has been -modified, and if so give the user a chance to save it. It then exits -from the program: - -<UL><PRE> -void quit_cb(Fl_Widget*, void*) { - if (changed && !check_save()) - return; - - exit(0); -} -</PRE></UL> - -<H3>replace_cb()</H3> - -<P>The replace callback just shows the replace dialog: - -<UL><PRE> -void replace_cb(Fl_Widget*, void* v) { - EditorWindow* e = (EditorWindow*)v; - e->replace_dlg->show(); -} -</PRE></UL> - -<H3>replace2_cb()</H3> - -<P>This callback will replace the next occurence of the replacement -string. If nothing has been entered for the replacement string, then -the replace dialog is displayed instead: - -<UL><PRE> -void replace2_cb(Fl_Widget*, void* v) { - EditorWindow* e = (EditorWindow*)v; - const char *find = e->replace_find->value(); - const char *replace = e->replace_with->value(); - - if (find[0] == '\0') { - // Search string is blank; get a new one... - e->replace_dlg->show(); - return; - } - - e->replace_dlg->hide(); - - int pos = e->editor->insert_position(); - int found = textbuf->search_forward(pos, find, &pos); - - if (found) { - // Found a match; update the position and replace text... - textbuf->select(pos, pos+strlen(find)); - textbuf->remove_selection(); - textbuf->insert(pos, replace); - textbuf->select(pos, pos+strlen(replace)); - e->editor->insert_position(pos+strlen(replace)); - e->editor->show_insert_position(); - } - else fl_alert("No occurrences of \'%s\' found!", find); -} -</PRE></UL> - -<H3>replall_cb()</H3> - -<P>This callback will replace all occurences of the search -string in the file: - -<UL><PRE> -void replall_cb(Fl_Widget*, void* v) { - EditorWindow* e = (EditorWindow*)v; - const char *find = e->replace_find->value(); - const char *replace = e->replace_with->value(); - - find = e->replace_find->value(); - if (find[0] == '\0') { - // Search string is blank; get a new one... - e->replace_dlg->show(); - return; - } - - e->replace_dlg->hide(); - - e->editor->insert_position(0); - int times = 0; - - // Loop through the whole string - for (int found = 1; found;) { - int pos = e->editor->insert_position(); - found = textbuf->search_forward(pos, find, &pos); - - if (found) { - // Found a match; update the position and replace text... - textbuf->select(pos, pos+strlen(find)); - textbuf->remove_selection(); - textbuf->insert(pos, replace); - e->editor->insert_position(pos+strlen(replace)); - e->editor->show_insert_position(); - times++; - } - } - - if (times) fl_message("Replaced %d occurrences.", times); - else fl_alert("No occurrences of \'%s\' found!", find); -} -</PRE></UL> - -<H3>replcan_cb()</H3> - -<P>This callback just hides the replace dialog: - -<UL><PRE> -void replcan_cb(Fl_Widget*, void* v) { - EditorWindow* e = (EditorWindow*)v; - e->replace_dlg->hide(); -} -</PRE></UL> - -<H3>save_cb()</H3> - -<P>This callback saves the current file. If the current filename is -blank it calls the "save as" callback: - -<UL><PRE> -void save_cb(void) { - if (filename[0] == '\0') { - // No filename - get one! - saveas_cb(); - return; - } - else save_file(filename); -} -</PRE></UL> - -<P>The <TT>save_file()</TT> function saves the current file to the -specified filename. - -<H3>saveas_cb()</H3> - -<P>This callback asks the user for a filename and saves the current file: - -<UL><PRE> -void saveas_cb(void) { - char *newfile; - - newfile = fl_file_chooser("Save File As?", "*", filename); - if (newfile != NULL) save_file(newfile); -} -</PRE></UL> - -<P>The <TT>save_file()</TT> function saves the current file to the -specified filename. - -<H2>Other Functions</H2> - -<P>Now that we've defined the callback functions, we need our support -functions to make it all work: - -<H3>check_save()</H3> - -<P>This function checks to see if the current file needs to be saved. If -so, it asks the user if they want to save it: - -<UL><PRE> -int check_save(void) { - if (!changed) return 1; - - int r = fl_choice("The current file has not been saved.\n" - "Would you like to save it now?", - "Cancel", "Save", "Discard"); - - if (r == 1) { - save_cb(); // Save the file... - return !changed; - } - - return (r == 2) ? 1 : 0; -} -</PRE></UL> - -<H3>load_file()</H3> - -<P>This function loads the specified file into the <TT>textbuf</TT> class: - -<UL><PRE> -int loading = 0; -void load_file(char *newfile, int ipos) { - loading = 1; - int insert = (ipos != -1); - changed = insert; - if (!insert) strcpy(filename, ""); - int r; - if (!insert) r = textbuf->loadfile(newfile); - else r = textbuf->insertfile(newfile, ipos); - if (r) - fl_alert("Error reading from file \'%s\':\n%s.", newfile, strerror(errno)); - else - if (!insert) strcpy(filename, newfile); - loading = 0; - textbuf->call_modify_callbacks(); -} -</PRE></UL> - -<P>When loading the file we use the <A -href="Fl_Text_Buffer.html#Fl_Text_Buffer.loadfile"><TT>loadfile()</TT></A> -method to "replace" the text in the buffer, or the <A -href="Fl_Text_Buffer.html#Fl_Text_Buffer.insertfile"><TT>insertfile()</TT></A> -method to insert text in the buffer from the named file. - -<H3>save_file()</H3> - -<P>This function saves the current buffer to the specified file: - -<UL><PRE> -void save_file(char *newfile) { - if (textbuf->savefile(newfile)) - fl_alert("Error writing to file \'%s\':\n%s.", newfile, strerror(errno)); - else - strcpy(filename, newfile); - changed = 0; - textbuf->call_modify_callbacks(); -} -</PRE></UL> - -<H3>set_title()</H3> - -<P>This function checks the <TT>changed</TT> variable and updates the -window label accordingly: -<UL><PRE> -void set_title(Fl_Window* w) { - if (filename[0] == '\0') strcpy(title, "Untitled"); - else { - char *slash; - slash = strrchr(filename, '/'); -#ifdef WIN32 - if (slash == NULL) slash = strrchr(filename, '\\'); -#endif - if (slash != NULL) strcpy(title, slash + 1); - else strcpy(title, filename); - } - - if (changed) strcat(title, " (modified)"); - - w->label(title); -} -</PRE></UL> - -<H2>The main() Function</H2> - -<P>Once we've created all of the support functions, the only thing left -is to tie them all together with the <TT>main()</TT> function. -The <TT>main()</TT> function creates a new text buffer, creates a -new view (window) for the text, shows the window, loads the file on -the command-line (if any), and then enters the FLTK event loop: - -<UL><PRE> -int main(int argc, char **argv) { - textbuf = new Fl_Text_Buffer; - - Fl_Window* window = new_view(); - - window->show(1, argv); - - if (argc > 1) load_file(argv[1], -1); - - return Fl::run(); -} -</PRE></UL> - -<H2>Compiling the Editor</H2> - -<P>The complete source for our text editor can be found in the <TT>test/editor.cxx</TT> source file. Both the Makefile and Visual C++ -workspace include the necessary rules to build the editor. You can -also compile it using a standard compiler with: - -<UL><PRE> -CC -o editor editor.cxx -lfltk -lXext -lX11 -lm -</PRE></UL> - -<P>or by using the <TT>fltk-config</TT> script with: - -<UL><PRE> -fltk-config --compile editor.cxx -</PRE></UL> - -<P>As noted in <A href="basics.html">Chapter 1</A>, you may need to -include compiler and linker options to tell them where to find the FLTK -library. Also, the <TT>CC</TT> command may also be called <TT>gcc</TT> -or <TT>c++</TT> on your system. - -<P>Congratulations, you've just built your own text editor!</P> - -<H2>The Final Product</H2> - -The final editor window should look like the image in Figure 4-2. - -<P ALIGN="CENTER"><IMG src="editor.gif" ALT="The completed editor window."><BR> -<I>Figure 4-2: The completed editor window</I></P> - -<H2>Advanced Features</H2> - -<P>Now that we've implemented the basic functionality, it is -time to show off some of the advanced features of the -<CODE>Fl_Text_Editor</CODE> widget. - -<H3>Syntax Highlighting</H3> - -<P>The <CODE>Fl_Text_Editor</CODE> widget supports highlighting -of text with different fonts, colors, and sizes. The -implementation is based on the excellent <A -HREF="http://www.nedit.org/">NEdit</A> text editor core, which -uses a parallel "style" buffer which tracks the font, color, and -size of the text that is drawn. - -<P>Styles are defined using the -<CODE>Fl_Text_Display::Style_Table_Entry</CODE> structure -defined in <CODE><FL/Fl_Text_Display.H></CODE>: - -<UL><PRE> -struct Style_Table_Entry { - Fl_Color color; - Fl_Font font; - int size; - unsigned attr; -}; -</PRE></UL> - -<P>The <CODE>color</CODE> member sets the color for the text, -the <CODE>font</CODE> member sets the FLTK font index to use, -and the <CODE>size</CODE> member sets the pixel size of the -text. The <CODE>attr</CODE> member is currently not used. - -<P>For our text editor we'll define 7 styles for plain code, -comments, keywords, and preprocessor directives: - -<UL><PRE> -Fl_Text_Display::Style_Table_Entry styletable[] = { // Style table - { FL_BLACK, FL_COURIER, FL_NORMAL_SIZE }, // A - Plain - { FL_DARK_GREEN, FL_COURIER_ITALIC, FL_NORMAL_SIZE }, // B - Line comments - { FL_DARK_GREEN, FL_COURIER_ITALIC, FL_NORMAL_SIZE }, // C - Block comments - { FL_BLUE, FL_COURIER, FL_NORMAL_SIZE }, // D - Strings - { FL_DARK_RED, FL_COURIER, FL_NORMAL_SIZE }, // E - Directives - { FL_DARK_RED, FL_COURIER_BOLD, FL_NORMAL_SIZE }, // F - Types - { FL_BLUE, FL_COURIER_BOLD, FL_NORMAL_SIZE } // G - Keywords -}; -</PRE></UL> - -<P>You'll notice that the comments show a letter next to each -style - each style in the style buffer is referenced using a -character starting with the letter 'A'. - -<P>You call the <CODE>highlight_data()</CODE> method to associate the -style data and buffer with the text editor widget: - -<UL><PRE> -Fl_Text_Buffer *stylebuf; - -w->editor->highlight_data(stylebuf, styletable, - sizeof(styletable) / sizeof(styletable[0]), - 'A', style_unfinished_cb, 0); -</PRE></UL> - -<P>Finally, you need to add a callback to the main text buffer so -that changes to the text buffer are mirrored in the style buffer: - -<UL><PRE> -textbuf->add_modify_callback(style_update, w->editor); -</PRE></UL> - -<P>The <CODE>style_update()</CODE> function, like the <CODE>change_cb()</CODE> -function described earlier, is called whenever text is added or removed from -the text buffer. It mirrors the changes in the style buffer and then updates -the style data as necessary: - -<UL><PRE> -// -// 'style_update()' - Update the style buffer... -// - -void -style_update(int pos, // I - Position of update - int nInserted, // I - Number of inserted chars - int nDeleted, // I - Number of deleted chars - int nRestyled, // I - Number of restyled chars - const char *deletedText, // I - Text that was deleted - void *cbArg) { // I - Callback data - int start, // Start of text - end; // End of text - char last, // Last style on line - *style, // Style data - *text; // Text data - - - // If this is just a selection change, just unselect the style buffer... - if (nInserted == 0 && nDeleted == 0) { - stylebuf->unselect(); - return; - } - - // Track changes in the text buffer... - if (nInserted > 0) { - // Insert characters into the style buffer... - style = new char[nInserted + 1]; - memset(style, 'A', nInserted); - style[nInserted] = '\0'; - - stylebuf->replace(pos, pos + nDeleted, style); - delete[] style; - } else { - // Just delete characters in the style buffer... - stylebuf->remove(pos, pos + nDeleted); - } - - // Select the area that was just updated to avoid unnecessary - // callbacks... - stylebuf->select(pos, pos + nInserted - nDeleted); - - // Re-parse the changed region; we do this by parsing from the - // beginning of the line of the changed region to the end of - // the line of the changed region... Then we check the last - // style character and keep updating if we have a multi-line - // comment character... - start = textbuf->line_start(pos); - end = textbuf->line_end(pos + nInserted - nDeleted); - text = textbuf->text_range(start, end); - style = stylebuf->text_range(start, end); - last = style[end - start - 1]; - - style_parse(text, style, end - start); - - stylebuf->replace(start, end, style); - ((Fl_Text_Editor *)cbArg)->redisplay_range(start, end); - - if (last != style[end - start - 1]) { - // The last character on the line changed styles, so reparse the - // remainder of the buffer... - free(text); - free(style); - - end = textbuf->length(); - text = textbuf->text_range(start, end); - style = stylebuf->text_range(start, end); - - style_parse(text, style, end - start); - - stylebuf->replace(start, end, style); - ((Fl_Text_Editor *)cbArg)->redisplay_range(start, end); - } - - free(text); - free(style); -} -</PRE></UL> - -<P>The <CODE>style_parse()</CODE> function scans a copy of the -text in the buffer and generates the necessary style characters -for display. It assumes that parsing begins at the start of a line: - -<UL><PRE> -// -// 'style_parse()' - Parse text and produce style data. -// - -void -style_parse(const char *text, - char *style, - int length) { - char current; - int col; - int last; - char buf[255], - *bufptr; - const char *temp; - - for (current = *style, col = 0, last = 0; length > 0; length --, text ++) { - if (current == 'A') { - // Check for directives, comments, strings, and keywords... - if (col == 0 && *text == '#') { - // Set style to directive - current = 'E'; - } else if (strncmp(text, "//", 2) == 0) { - current = 'B'; - } else if (strncmp(text, "/*", 2) == 0) { - current = 'C'; - } else if (strncmp(text, "\\\"", 2) == 0) { - // Quoted quote... - *style++ = current; - *style++ = current; - text ++; - length --; - col += 2; - continue; - } else if (*text == '\"') { - current = 'D'; - } else if (!last && islower(*text)) { - // Might be a keyword... - for (temp = text, bufptr = buf; - islower(*temp) && bufptr < (buf + sizeof(buf) - 1); - *bufptr++ = *temp++); - - if (!islower(*temp)) { - *bufptr = '\0'; - - bufptr = buf; - - if (bsearch(&bufptr, code_types, - sizeof(code_types) / sizeof(code_types[0]), - sizeof(code_types[0]), compare_keywords)) { - while (text < temp) { - *style++ = 'F'; - text ++; - length --; - col ++; - } - - text --; - length ++; - last = 1; - continue; - } else if (bsearch(&bufptr, code_keywords, - sizeof(code_keywords) / sizeof(code_keywords[0]), - sizeof(code_keywords[0]), compare_keywords)) { - while (text < temp) { - *style++ = 'G'; - text ++; - length --; - col ++; - } - - text --; - length ++; - last = 1; - continue; - } - } - } - } else if (current == 'C' && strncmp(text, "*/", 2) == 0) { - // Close a C comment... - *style++ = current; - *style++ = current; - text ++; - length --; - current = 'A'; - col += 2; - continue; - } else if (current == 'D') { - // Continuing in string... - if (strncmp(text, "\\\"", 2) == 0) { - // Quoted end quote... - *style++ = current; - *style++ = current; - text ++; - length --; - col += 2; - continue; - } else if (*text == '\"') { - // End quote... - *style++ = current; - col ++; - current = 'A'; - continue; - } - } - - // Copy style info... - if (current == 'A' && (*text == '{' || *text == '}')) *style++ = 'G'; - else *style++ = current; - col ++; - - last = isalnum(*text) || *text == '.'; - - if (*text == '\n') { - // Reset column and possibly reset the style - col = 0; - if (current == 'B' || current == 'E') current = 'A'; - } - } -} -</PRE></UL> - - -</BODY> -</HTML> |