GUACAMOLE-192: Select word in terminal on double click

src/terminal/select.c

@@ -194,7 +194,7 @@ void guac_terminal_select_update(guac_terminal* terminal, int row, int column) {
 
     /* Only update if selection has changed */
     if (row != terminal->selection_end_row
-        || column <  terminal->selection_end_column
+        || column <=  terminal->selection_end_column
         || column >= terminal->selection_end_column + terminal->selection_end_width) {
 
         int width = guac_terminal_find_char(terminal, row, &column);

src/terminal/terminal.c

@@ -590,6 +590,10 @@ guac_terminal* guac_terminal_create(guac_client* client,
     /* Configure backspace */
     term->backspace = options->backspace;
 
+    /* Initialize mouse latest click time and counter */
+    term->click_timer = 0;
+    term->click_counter = 0;
+
     return term;
 
 }
@@ -1748,6 +1752,132 @@ int guac_terminal_send_key(guac_terminal* term, int keysym, int pressed) {
 
 }
 
+/**
+ * Determines if the given character is part of a word.
+ * Match these chars :[0-9A-Za-z\$\%\&\-\.\/\:\=\?\\_~]
+ * This allows a path, URL, variable name or IP address to be treated as a word.
+ *
+ * @param ascii_char
+ *     The character to check.
+ *
+ * @return
+ *     true if match a "word" char,
+ *     false otherwise.
+ */
+static bool guac_terminal_is_part_of_word(int ascii_char) {
+    return ((ascii_char >= '0' && ascii_char <= '9') || 
+            (ascii_char >= 'A' && ascii_char <= 'Z') || 
+            (ascii_char >= 'a' && ascii_char <= 'z') ||
+            (ascii_char == '$') ||
+            (ascii_char == '%') ||
+            (ascii_char == '&') ||
+            (ascii_char == '-') ||
+            (ascii_char == '.') ||
+            (ascii_char == '/') ||
+            (ascii_char == ':') ||
+            (ascii_char == '=') ||
+            (ascii_char == '?') ||
+            (ascii_char == '\\') ||
+            (ascii_char == '_') ||
+            (ascii_char == '~'));
+}
+
+/**
+ * Determines if the given character is part of blank block.
+ *
+ * @param ascii_char
+ *     The character to check.
+ *
+ * @return
+ *     true if match space (char 0x20) or NULL (char 0x00),
+ *     false otherwise.
+ */
+static bool guac_terminal_is_blank(int ascii_char) {
+    return (ascii_char == '\0' || ascii_char == ' ');
+}
+
+/**
+ * Get the char (int ASCII code) at a specific row/col of the display.
+ *
+ * @param terminal
+ *     The terminal on which we want to read a character.
+ *
+ * @param row
+ *     The row where to read the character.
+ * 
+ * @param col
+ *     The column where to read the character.
+ * 
+ * @return
+ *     The ASCII code of the character at the given row/col.
+ */
+static int guac_terminal_get_char(guac_terminal* terminal, int row, int col) {
+    guac_terminal_buffer_row* buffer_row = guac_terminal_buffer_get_row(terminal->buffer, row, 0);
+    guac_terminal_char* ascii_char = &(buffer_row->characters[col]);
+
+    return ascii_char->value;
+}
+
+/**
+ * Selection of a word during a double click event.
+ *  - Fetching the character under the mouse cursor.
+ *  - Determining the type of character :
+ *      Letter, digit, acceptable symbol within a word,
+ *      or space/NULL,
+ *      all other chars are treated as single. 
+ *  - Calculating the word boundaries.
+ *  - Visual selection of the found word.
+ *  - Adding it to clipboard.
+ *
+ * @param terminal
+ *     The terminal that received a double click event.
+ *
+ * @param row
+ *     The row where is the mouse at the double click event.
+ * 
+ * @param col
+ *     The column where is the mouse at the double click event.
+ */
+static void guac_terminal_double_click(guac_terminal* terminal, int row, int col) {
+
+    /* (char)10 behind cursor */
+    int cursor_char = guac_terminal_get_char(terminal, row, col);
+
+    /* Position of the word behind cursor. 
+     * Default = col required to select a char if not a word and not blank. */
+    int word_head = col;
+    int word_tail = col;
+    int flag;
+
+    /* The function used to calculate the word borders */
+    bool (*is_part_of_word)(int) = NULL;
+
+    /* If selection is on a word, get its borders */
+    if (guac_terminal_is_part_of_word(cursor_char))
+        is_part_of_word = guac_terminal_is_part_of_word;
+
+    /* If selection is on a blank, get its borders */
+    else if (guac_terminal_is_blank(cursor_char))
+        is_part_of_word = guac_terminal_is_blank;
+
+    if (is_part_of_word != NULL) {
+        /* Get word head*/
+        do {
+            flag = guac_terminal_get_char(terminal, row, word_head-1);
+        } while (is_part_of_word(flag) && (word_head >= 0 && word_head <= terminal->display->width) && word_head--);
+
+        /* Get word tail */
+        do {
+            flag = guac_terminal_get_char(terminal, row, word_tail+1);
+        } while (is_part_of_word(flag) && (word_tail >= 0 && word_tail <= terminal->display->width) && word_tail++);
+    }
+
+    /* Select and add to clipboard the "word" */
+    guac_terminal_select_start(terminal, row, word_head);
+    guac_terminal_select_update(terminal, row, word_tail);
+
+}
+
 static int __guac_terminal_send_mouse(guac_terminal* term, guac_user* user,
         int x, int y, int mask) {
 
@@ -1813,8 +1943,34 @@ static int __guac_terminal_send_mouse(guac_terminal* term, guac_user* user,
         if (pressed_mask & GUAC_CLIENT_MOUSE_LEFT) {
             if (term->mod_shift)
                 guac_terminal_select_resume(term, row, col);
-            else
-                guac_terminal_select_start(term, row, col);
+            else {
+
+                /* Reset click counter if last click was 300ms before */
+                if (guac_timestamp_current() - term->click_timer > 300)
+                    term->click_counter = 0;
+
+                /* New click time */
+                term->click_timer = guac_timestamp_current();
+
+                switch (term->click_counter++) {
+
+                    /* First click = start selection */
+                    case 0:
+                        guac_terminal_select_start(term, row, col);
+                        break;
+
+                    /* Second click = word selection */
+                    case 1:
+                        guac_terminal_double_click(term, row, col);
+                        break;
+
+                    /* third click or more = line selection */
+                    default:
+                        guac_terminal_select_start(term, row, 0);
+                        guac_terminal_select_update(term, row, term->display->width);
+                        break;
+                }
+            }
         }
 
         /* In all other cases, simply update the existing selection as long as

src/terminal/terminal/terminal-priv.h

@@ -465,6 +465,16 @@ struct guac_terminal {
      */
     bool disable_copy;
 
+    /**
+     * The time betwen two left clicks.
+     */
+    guac_timestamp click_timer;
+
+    /**
+     * Counter for left clicks.
+     */
+    int click_counter;
+
 };
 
 /**