GUACAMOLE-573: Merge allow selection of text while scrolling.

src/terminal/Makefile.am

@@ -30,6 +30,7 @@ noinst_HEADERS =                 \
     terminal/named-colors.h      \
     terminal/palette.h           \
     terminal/scrollbar.h         \
+    terminal/select.h            \
     terminal/terminal.h          \
     terminal/terminal_handlers.h \
     terminal/types.h             \
@@ -44,6 +45,7 @@ libguac_terminal_la_SOURCES =   \
     named-colors.c              \
     palette.c                   \
     scrollbar.c                 \
+    select.c                    \
     terminal.c                  \
     terminal_handlers.c         \
     typescript.c                \

src/terminal/display.c

@@ -37,54 +37,6 @@
 #include <guacamole/socket.h>
 #include <pango/pangocairo.h>
 
-/**
- * Clears the currently-selected region, removing the highlight.
- */
-static void __guac_terminal_display_clear_select(guac_terminal_display* display) {
-
-    guac_socket* socket = display->client->socket;
-    guac_layer* select_layer = display->select_layer;
-
-    guac_protocol_send_rect(socket, select_layer, 0, 0, 1, 1);
-    guac_protocol_send_cfill(socket, GUAC_COMP_SRC, select_layer,
-            0x00, 0x00, 0x00, 0x00);
-
-    guac_client_end_frame(display->client);
-    guac_socket_flush(socket);
-
-    /* Text is no longer selected */
-    display->text_selected =
-    display->selection_committed = false;
-
-}
-
-/**
- * Returns whether at least one character within the given range is selected.
- */
-static bool __guac_terminal_display_selected_contains(guac_terminal_display* display,
-        int start_row, int start_column, int end_row, int end_column) {
-
-    /* If test range starts after highlight ends, does not intersect */
-    if (start_row > display->selection_end_row)
-        return false;
-
-    if (start_row == display->selection_end_row
-            && start_column > display->selection_end_column)
-        return false;
-
-    /* If test range ends before highlight starts, does not intersect */
-    if (end_row < display->selection_start_row)
-        return false;
-
-    if (end_row == display->selection_start_row
-            && end_column < display->selection_start_column)
-        return false;
-
-    /* Otherwise, does intersect */
-    return true;
-
-}
-
 /* Maps any codepoint onto a number between 0 and 511 inclusive */
 int __guac_terminal_hash_codepoint(int codepoint) {
 
@@ -310,8 +262,7 @@ guac_terminal_display* guac_terminal_display_alloc(guac_client* client,
     display->operations = NULL;
 
     /* Initially nothing selected */
-    display->text_selected =
+    display->text_selected = false;
-    display->selection_committed = false;
 
     return display;
 
@@ -413,11 +364,6 @@ void guac_terminal_display_copy_columns(guac_terminal_display* display, int row,
 
     }
 
-    /* If selection visible and committed, clear if update touches selection */
-    if (display->text_selected && display->selection_committed &&
-        __guac_terminal_display_selected_contains(display, row, start_column, row, end_column))
-            __guac_terminal_display_clear_select(display);
-
 }
 
 void guac_terminal_display_copy_rows(guac_terminal_display* display,
@@ -463,11 +409,6 @@ void guac_terminal_display_copy_rows(guac_terminal_display* display,
 
     }
 
-    /* If selection visible and committed, clear if update touches selection */
-    if (display->text_selected && display->selection_committed &&
-        __guac_terminal_display_selected_contains(display, start_row, 0, end_row, display->width - 1))
-            __guac_terminal_display_clear_select(display);
-
 }
 
 void guac_terminal_display_set_columns(guac_terminal_display* display, int row,
@@ -502,11 +443,6 @@ void guac_terminal_display_set_columns(guac_terminal_display* display, int row,
 
     }
 
-    /* If selection visible and committed, clear if update touches selection */
-    if (display->text_selected && display->selection_committed &&
-        __guac_terminal_display_selected_contains(display, row, start_column, row, end_column))
-            __guac_terminal_display_clear_select(display);
-
 }
 
 void guac_terminal_display_resize(guac_terminal_display* display, int width, int height) {
@@ -570,10 +506,6 @@ void guac_terminal_display_resize(guac_terminal_display* display, int width, int
             display->char_width  * width,
             display->char_height * height);
 
-    /* If selection visible and committed, clear */
-    if (display->text_selected && display->selection_committed)
-        __guac_terminal_display_clear_select(display);
-
 }
 
 void __guac_terminal_display_flush_copy(guac_terminal_display* display) {
@@ -899,16 +831,20 @@ void guac_terminal_display_dup(guac_terminal_display* display, guac_user* user,
 
 }
 
-void guac_terminal_display_commit_select(guac_terminal_display* display) {
-    display->selection_committed = true;
-}
-
 void guac_terminal_display_select(guac_terminal_display* display,
         int start_row, int start_col, int end_row, int end_col) {
 
     guac_socket* socket = display->client->socket;
     guac_layer* select_layer = display->select_layer;
 
+    /* Do nothing if selection is unchanged */
+    if (display->text_selected
+            && display->selection_start_row    == start_row
+            && display->selection_start_column == start_col
+            && display->selection_end_row      == end_row
+            && display->selection_end_column   == end_col)
+        return;
+
     /* Text is now selected */
     display->text_selected = true;
 
@@ -989,8 +925,24 @@ void guac_terminal_display_select(guac_terminal_display* display,
     guac_protocol_send_cfill(socket, GUAC_COMP_SRC, select_layer,
             0x00, 0x80, 0xFF, 0x60);
 
-    guac_client_end_frame(display->client);
+}
-    guac_socket_flush(socket);
+
+void guac_terminal_display_clear_select(guac_terminal_display* display) {
+
+    /* Do nothing if nothing is selected */
+    if (!display->text_selected)
+        return;
+
+    guac_socket* socket = display->client->socket;
+    guac_layer* select_layer = display->select_layer;
+
+    guac_protocol_send_rect(socket, select_layer, 0, 0, 1, 1);
+    guac_protocol_send_cfill(socket, GUAC_COMP_SRC, select_layer,
+            0x00, 0x00, 0x00, 0x00);
+
+    /* Text is no longer selected */
+    display->text_selected = false;
 
 }
 
+

src/terminal/select.c

@@ -0,0 +1,452 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include "config.h"
+
+#include "common/clipboard.h"
+#include "terminal/buffer.h"
+#include "terminal/display.h"
+#include "terminal/select.h"
+#include "terminal/terminal.h"
+#include "terminal/types.h"
+
+#include <guacamole/client.h>
+#include <guacamole/socket.h>
+#include <guacamole/unicode.h>
+
+#include <stdbool.h>
+
+/**
+ * Returns the coordinates for the currently-selected range of text within the
+ * given terminal, normalized such that the start coordinate is before the end
+ * coordinate and the end coordinate takes into account character width. If no
+ * text is currently selected, the behavior of this function is undefined.
+ *
+ * @param terminal
+ *     The guac_terminal instance whose selected text coordinates should be
+ *     retrieved in normalized form.
+ *
+ * @param start_row
+ *     A pointer to an int which should receive the row number of the first
+ *     character of text selected within the terminal, where the first
+ *     (top-most) row in the terminal is row 0. Rows within the scrollback
+ *     buffer (above the top-most row of the terminal) will be negative.
+ *
+ * @param start_col
+ *     A pointer to an int which should receive the column number of the first
+ *     character of text selected within terminal, where 0 is the first
+ *     (left-most) column within the row.
+ *
+ * @param end_row
+ *     A pointer to an int which should receive the row number of the last
+ *     character of text selected within the terminal, where the first
+ *     (top-most) row in the terminal is row 0. Rows within the scrollback
+ *     buffer (above the top-most row of the terminal) will be negative.
+ *
+ * @param end_col
+ *     A pointer to an int which should receive the column number of the first
+ *     character of text selected within terminal, taking into account the
+ *     width of that character, where 0 is the first (left-most) column within
+ *     the row.
+ */
+static void guac_terminal_select_normalized_range(guac_terminal* terminal,
+        int* start_row, int* start_col, int* end_row, int* end_col) {
+
+    /* Pass through start/end coordinates if they are already in the expected
+     * order, adjusting only for final character width */
+    if (terminal->selection_start_row < terminal->selection_end_row
+        || (terminal->selection_start_row == terminal->selection_end_row
+            && terminal->selection_start_column < terminal->selection_end_column)) {
+
+        *start_row = terminal->selection_start_row;
+        *start_col = terminal->selection_start_column;
+        *end_row   = terminal->selection_end_row;
+        *end_col   = terminal->selection_end_column + terminal->selection_end_width - 1;
+
+    }
+
+    /* Coordinates must otherwise be swapped in addition to adjusting for
+     * final character width */
+    else {
+        *end_row   = terminal->selection_start_row;
+        *end_col   = terminal->selection_start_column + terminal->selection_start_width - 1;
+        *start_row = terminal->selection_end_row;
+        *start_col = terminal->selection_end_column;
+    }
+
+}
+
+void guac_terminal_select_redraw(guac_terminal* terminal) {
+
+    /* Update the selected region of the display if text is currently
+     * selected */
+    if (terminal->text_selected) {
+
+        int start_row = terminal->selection_start_row + terminal->scroll_offset;
+        int start_column = terminal->selection_start_column;
+
+        int end_row = terminal->selection_end_row + terminal->scroll_offset;
+        int end_column = terminal->selection_end_column;
+
+        /* Update start/end columns to include character width */
+        if (start_row > end_row || (start_row == end_row && start_column > end_column))
+            start_column += terminal->selection_start_width - 1;
+        else
+            end_column += terminal->selection_end_width - 1;
+
+        guac_terminal_display_select(terminal->display, start_row, start_column, end_row, end_column);
+
+    }
+
+    /* Clear the display selection if no text is currently selected */
+    else
+        guac_terminal_display_clear_select(terminal->display);
+
+}
+
+/**
+ * Locates the beginning of the character at the given row and column, updating
+ * the column to the starting column of that character. The width, if available,
+ * is returned. If the character has no defined width, 1 is returned.
+ *
+ * @param terminal
+ *     The guac_terminal in which the character should be located.
+ *
+ * @param row
+ *     The row number of the desired character, where the first (top-most) row
+ *     in the terminal is row 0. Rows within the scrollback buffer (above the
+ *     top-most row of the terminal) will be negative.
+ *
+ * @param column
+ *     A pointer to an int containing the column number of the desired
+ *     character, where 0 is the first (left-most) column within the row. If
+ *     the character is a multi-column character, the value of this int will be
+ *     adjusted as necessary such that it contains the column number of the
+ *     first column containing the character.
+ *
+ * @return
+ *     The width of the specified character, in columns, or 1 if the character
+ *     has no defined width.
+ */
+static int guac_terminal_find_char(guac_terminal* terminal,
+        int row, int* column) {
+
+    int start_column = *column;
+
+    /* If requested row is outside the bounds of the current terminal or
+     * scrollback, assume the character is 1 column wide */
+    if (row >= terminal->term_height
+            || row < terminal->term_height - terminal->buffer->length)
+        return 1;
+
+    guac_terminal_buffer_row* buffer_row = guac_terminal_buffer_get_row(terminal->buffer, row, 0);
+    if (start_column < buffer_row->length) {
+
+        /* Find beginning of character */
+        guac_terminal_char* start_char = &(buffer_row->characters[start_column]);
+        while (start_column > 0 && start_char->value == GUAC_CHAR_CONTINUATION) {
+            start_char--;
+            start_column--;
+        }
+
+        /* Use width, if available */
+        if (start_char->value != GUAC_CHAR_CONTINUATION) {
+            *column = start_column;
+            return start_char->width;
+        }
+
+    }
+
+    /* Default to one column wide */
+    return 1;
+
+}
+
+void guac_terminal_select_start(guac_terminal* terminal, int row, int column) {
+
+    int width = guac_terminal_find_char(terminal, row, &column);
+
+    terminal->selection_start_row =
+    terminal->selection_end_row   = row;
+
+    terminal->selection_start_column =
+    terminal->selection_end_column   = column;
+
+    terminal->selection_start_width =
+    terminal->selection_end_width   = width;
+
+    terminal->text_selected = false;
+    terminal->selection_committed = false;
+    guac_terminal_notify(terminal);
+
+}
+
+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 + terminal->selection_end_width) {
+
+        int width = guac_terminal_find_char(terminal, row, &column);
+
+        terminal->selection_end_row = row;
+        terminal->selection_end_column = column;
+        terminal->selection_end_width = width;
+        terminal->text_selected = true;
+
+        guac_terminal_notify(terminal);
+
+    }
+
+}
+
+void guac_terminal_select_resume(guac_terminal* terminal, int row, int column) {
+
+    int selection_start_row;
+    int selection_start_column;
+    int selection_end_row;
+    int selection_end_column;
+
+    /* No need to test coordinates if no text is selected at all */
+    if (!terminal->text_selected)
+        return;
+
+    /* Use normalized coordinates for sake of simple comparison */
+    guac_terminal_select_normalized_range(terminal,
+            &selection_start_row, &selection_start_column,
+            &selection_end_row, &selection_end_column);
+
+    /* Prefer to expand from start, such that attempting to resume a selection
+     * within the existing selection preserves the top-most portion of the
+     * selection */
+    if (row > selection_start_row ||
+            (row == selection_start_row && column > selection_start_column)) {
+        terminal->selection_start_row = selection_start_row;
+        terminal->selection_start_column = selection_start_column;
+    }
+
+    /* Expand from bottom-most portion of selection if doing otherwise would
+     * reduce the size of the selection */
+    else {
+        terminal->selection_start_row = selection_end_row;
+        terminal->selection_start_column = selection_end_column;
+    }
+
+    /* Selection is again in-progress */
+    terminal->selection_committed = false;
+
+    /* Update selection to contain given character */
+    guac_terminal_select_update(terminal, row, column);
+
+}
+
+/**
+ * Appends the text within the given subsection of a terminal row to the
+ * clipboard. The provided coordinates are considered inclusiveley (the
+ * characters at the start and end column are included in the copied
+ * text). Any out-of-bounds coordinates will be automatically clipped within
+ * the bounds of the given row.
+ *
+ * @param terminal
+ *     The guac_terminal instance associated with the buffer containing the
+ *     text being copied and the clipboard receiving the copied text.
+ *
+ * @param row
+ *     The row number of the text within the terminal to be copied into the
+ *     clipboard, where the first (top-most) row in the terminal is row 0. Rows
+ *     within the scrollback buffer (above the top-most row of the terminal)
+ *     will be negative.
+ *
+ * @param start
+ *     The first column of the text to be copied from the given row into the
+ *     clipboard associated with the given terminal, where 0 is the first
+ *     (left-most) column within the row.
+ *
+ * @param end
+ *     The last column of the text to be copied from the given row into the
+ *     clipboard associated with the given terminal, where 0 is the first
+ *     (left-most) column within the row, or a negative value to denote that
+ *     the last column in the row should be used.
+ */
+static void guac_terminal_clipboard_append_row(guac_terminal* terminal,
+        int row, int start, int end) {
+
+    char buffer[1024];
+    int i = start;
+
+    /* If requested row is outside the bounds of the current terminal or
+     * scrollback, do nothing */
+    if (row >= terminal->term_height
+            || row < terminal->term_height - terminal->buffer->length)
+        return;
+
+    guac_terminal_buffer_row* buffer_row =
+        guac_terminal_buffer_get_row(terminal->buffer, row, 0);
+
+    /* If selection is entirely outside the bounds of the row, then there is
+     * nothing to append */
+    if (start < 0 || start > buffer_row->length - 1)
+        return;
+
+    /* Clip given range to actual bounds of row */
+    if (end < 0 || end > buffer_row->length - 1)
+        end = buffer_row->length - 1;
+
+    /* Repeatedly convert chunks of terminal buffer rows until entire specified
+     * region has been appended to clipboard */
+    while (i <= end) {
+
+        int remaining = sizeof(buffer);
+        char* current = buffer;
+
+        /* Convert as many codepoints within the given range as possible */
+        for (i = start; i <= end; i++) {
+
+            int codepoint = buffer_row->characters[i].value;
+
+            /* Ignore null (blank) characters */
+            if (codepoint == 0 || codepoint == GUAC_CHAR_CONTINUATION)
+                continue;
+
+            /* Encode current codepoint as UTF-8 */
+            int bytes = guac_utf8_write(codepoint, current, remaining);
+            if (bytes == 0)
+                break;
+
+            current += bytes;
+            remaining -= bytes;
+
+        }
+
+        /* Append converted buffer to clipboard */
+        guac_common_clipboard_append(terminal->clipboard, buffer, current - buffer);
+
+    }
+
+}
+
+void guac_terminal_select_end(guac_terminal* terminal) {
+
+    guac_client* client = terminal->client;
+    guac_socket* socket = client->socket;
+
+    /* If no text is selected, nothing to do */
+    if (!terminal->text_selected)
+        return;
+
+    /* Selection is now committed */
+    terminal->selection_committed = true;
+
+    /* Reset current clipboard contents */
+    guac_common_clipboard_reset(terminal->clipboard, "text/plain");
+
+    int start_row, start_col;
+    int end_row, end_col;
+
+    /* Ensure proper ordering of start and end coords */
+    guac_terminal_select_normalized_range(terminal,
+            &start_row, &start_col, &end_row, &end_col);
+
+    /* If only one row, simply copy */
+    if (end_row == start_row)
+        guac_terminal_clipboard_append_row(terminal, start_row, start_col, end_col);
+
+    /* Otherwise, copy multiple rows */
+    else {
+
+        /* Store first row */
+        guac_terminal_clipboard_append_row(terminal, start_row, start_col, -1);
+
+        /* Store all middle rows */
+        for (int row = start_row + 1; row < end_row; row++) {
+            guac_common_clipboard_append(terminal->clipboard, "\n", 1);
+            guac_terminal_clipboard_append_row(terminal, row, 0, -1);
+        }
+
+        /* Store last row */
+        guac_common_clipboard_append(terminal->clipboard, "\n", 1);
+        guac_terminal_clipboard_append_row(terminal, end_row, 0, end_col);
+
+    }
+
+    /* Send data */
+    guac_common_clipboard_send(terminal->clipboard, client);
+    guac_socket_flush(socket);
+
+    guac_terminal_notify(terminal);
+
+}
+
+bool guac_terminal_select_contains(guac_terminal* terminal,
+        int start_row, int start_column, int end_row, int end_column) {
+
+    int selection_start_row;
+    int selection_start_column;
+    int selection_end_row;
+    int selection_end_column;
+
+    /* No need to test coordinates if no text is selected at all */
+    if (!terminal->text_selected)
+        return false;
+
+    /* Use normalized coordinates for sake of simple comparison */
+    guac_terminal_select_normalized_range(terminal,
+            &selection_start_row, &selection_start_column,
+            &selection_end_row, &selection_end_column);
+
+    /* If test range starts after highlight ends, does not intersect */
+    if (start_row > selection_end_row)
+        return false;
+
+    if (start_row == selection_end_row && start_column > selection_end_column)
+        return false;
+
+    /* If test range ends before highlight starts, does not intersect */
+    if (end_row < selection_start_row)
+        return false;
+
+    if (end_row == selection_start_row && end_column < selection_start_column)
+        return false;
+
+    /* Otherwise, does intersect */
+    return true;
+
+}
+
+void guac_terminal_select_touch(guac_terminal* terminal,
+        int start_row, int start_column, int end_row, int end_column) {
+
+    /* Only clear selection if selection is committed */
+    if (!terminal->selection_committed)
+        return;
+
+    /* Clear selection if it contains any characters within the given region */
+    if (guac_terminal_select_contains(terminal, start_row, start_column,
+                end_row, end_column)) {
+
+        /* Text is no longer selected */
+        terminal->text_selected = false;
+        terminal->selection_committed = false;
+        guac_terminal_notify(terminal);
+
+    }
+
+}
+

src/terminal/terminal.c

@@ -25,6 +25,7 @@
 #include "terminal/common.h"
 #include "terminal/display.h"
 #include "terminal/palette.h"
+#include "terminal/select.h"
 #include "terminal/terminal.h"
 #include "terminal/terminal_handlers.h"
 #include "terminal/types.h"
@@ -60,6 +61,9 @@ static void __guac_terminal_set_columns(guac_terminal* terminal, int row,
     guac_terminal_buffer_set_columns(terminal->buffer, row,
             start_column, end_column, character);
 
+    /* Clear selection if region is modified */
+    guac_terminal_select_touch(terminal, row, start_column, row, end_column);
+
 }
 
 /**
@@ -172,6 +176,7 @@ void guac_terminal_reset(guac_terminal* term) {
 
     /* Reset flags */
     term->text_selected = false;
+    term->selection_committed = false;
     term->application_cursor_keys = false;
     term->automatic_carriage_return = false;
     term->insert_mode = false;
@@ -1018,6 +1023,12 @@ int guac_terminal_scroll_up(guac_terminal* term,
             term->visible_cursor_row <= end_row)
             term->visible_cursor_row -= amount;
 
+        /* Update selected region */
+        if (term->text_selected) {
+            term->selection_start_row -= amount;
+            term->selection_end_row -= amount;
+        }
+
     }
 
     /* Otherwise, just copy row data upwards */
@@ -1269,184 +1280,6 @@ void guac_terminal_scroll_display_up(guac_terminal* terminal,
 
 }
 
-void guac_terminal_select_redraw(guac_terminal* terminal) {
-
-    int start_row = terminal->selection_start_row + terminal->scroll_offset;
-    int start_column = terminal->selection_start_column;
-
-    int end_row = terminal->selection_end_row + terminal->scroll_offset;
-    int end_column = terminal->selection_end_column;
-
-    /* Update start/end columns to include character width */
-    if (start_row > end_row || (start_row == end_row && start_column > end_column))
-        start_column += terminal->selection_start_width - 1;
-    else
-        end_column += terminal->selection_end_width - 1;
-
-    guac_terminal_display_select(terminal->display, start_row, start_column, end_row, end_column);
-
-}
-
-/**
- * Locates the beginning of the character at the given row and column, updating
- * the column to the starting column of that character. The width, if available,
- * is returned. If the character has no defined width, 1 is returned.
- */
-static int __guac_terminal_find_char(guac_terminal* terminal, int row, int* column) {
-
-    int start_column = *column;
-
-    guac_terminal_buffer_row* buffer_row = guac_terminal_buffer_get_row(terminal->buffer, row, 0);
-    if (start_column < buffer_row->length) {
-
-        /* Find beginning of character */
-        guac_terminal_char* start_char = &(buffer_row->characters[start_column]);
-        while (start_column > 0 && start_char->value == GUAC_CHAR_CONTINUATION) {
-            start_char--;
-            start_column--;
-        }
-
-        /* Use width, if available */
-        if (start_char->value != GUAC_CHAR_CONTINUATION) {
-            *column = start_column;
-            return start_char->width;
-        }
-
-    }
-
-    /* Default to one column wide */
-    return 1;
-
-}
-
-void guac_terminal_select_start(guac_terminal* terminal, int row, int column) {
-
-    int width = __guac_terminal_find_char(terminal, row, &column);
-
-    terminal->selection_start_row = 
-    terminal->selection_end_row   = row;
-
-    terminal->selection_start_column = 
-    terminal->selection_end_column   = column;
-
-    terminal->selection_start_width = 
-    terminal->selection_end_width   = width;
-
-    terminal->text_selected = true;
-
-    guac_terminal_select_redraw(terminal);
-
-}
-
-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 + terminal->selection_end_width) {
-
-        int width = __guac_terminal_find_char(terminal, row, &column);
-
-        terminal->selection_end_row = row;
-        terminal->selection_end_column = column;
-        terminal->selection_end_width = width;
-
-        guac_terminal_select_redraw(terminal);
-    }
-
-}
-
-int __guac_terminal_buffer_string(guac_terminal_buffer_row* row, int start, int end, char* string) {
-
-    int length = 0;
-    int i;
-    for (i=start; i<=end; i++) {
-
-        int codepoint = row->characters[i].value;
-
-        /* If not null (blank), add to string */
-        if (codepoint != 0 && codepoint != GUAC_CHAR_CONTINUATION) {
-            int bytes = guac_terminal_encode_utf8(codepoint, string);
-            string += bytes;
-            length += bytes;
-        }
-
-    }
-
-    return length;
-
-}
-
-void guac_terminal_select_end(guac_terminal* terminal, char* string) {
-
-    /* Deselect */
-    terminal->text_selected = false;
-    guac_terminal_display_commit_select(terminal->display);
-
-    guac_terminal_buffer_row* buffer_row;
-
-    int row;
-
-    int start_row, start_col;
-    int end_row, end_col;
-
-    /* Ensure proper ordering of start and end coords */
-    if (terminal->selection_start_row < terminal->selection_end_row
-        || (terminal->selection_start_row == terminal->selection_end_row
-            && terminal->selection_start_column < terminal->selection_end_column)) {
-
-        start_row = terminal->selection_start_row;
-        start_col = terminal->selection_start_column;
-        end_row   = terminal->selection_end_row;
-        end_col   = terminal->selection_end_column + terminal->selection_end_width - 1;
-
-    }
-    else {
-        end_row   = terminal->selection_start_row;
-        end_col   = terminal->selection_start_column + terminal->selection_start_width - 1;
-        start_row = terminal->selection_end_row;
-        start_col = terminal->selection_end_column;
-    }
-
-    /* If only one row, simply copy */
-    buffer_row = guac_terminal_buffer_get_row(terminal->buffer, start_row, 0);
-    if (end_row == start_row) {
-        if (buffer_row->length - 1 < end_col)
-            end_col = buffer_row->length - 1;
-        string += __guac_terminal_buffer_string(buffer_row, start_col, end_col, string);
-    }
-
-    /* Otherwise, copy multiple rows */
-    else {
-
-        /* Store first row */
-        string += __guac_terminal_buffer_string(buffer_row, start_col, buffer_row->length - 1, string);
-
-        /* Store all middle rows */
-        for (row=start_row+1; row<end_row; row++) {
-
-            buffer_row = guac_terminal_buffer_get_row(terminal->buffer, row, 0);
-
-            *(string++) = '\n';
-            string += __guac_terminal_buffer_string(buffer_row, 0, buffer_row->length - 1, string);
-
-        }
-
-        /* Store last row */
-        buffer_row = guac_terminal_buffer_get_row(terminal->buffer, end_row, 0);
-        if (buffer_row->length - 1 < end_col)
-            end_col = buffer_row->length - 1;
-
-        *(string++) = '\n';
-        string += __guac_terminal_buffer_string(buffer_row, 0, end_col, string);
-
-    }
-
-    /* Null terminator */
-    *string = 0;
-
-}
-
 void guac_terminal_copy_columns(guac_terminal* terminal, int row,
         int start_column, int end_column, int offset) {
 
@@ -1456,6 +1289,9 @@ void guac_terminal_copy_columns(guac_terminal* terminal, int row,
     guac_terminal_buffer_copy_columns(terminal->buffer, row,
             start_column, end_column, offset);
 
+    /* Clear selection if region is modified */
+    guac_terminal_select_touch(terminal, row, start_column, row, end_column);
+
     /* Update cursor location if within region */
     if (row == terminal->visible_cursor_row &&
             terminal->visible_cursor_col >= start_column &&
@@ -1477,6 +1313,10 @@ void guac_terminal_copy_rows(guac_terminal* terminal,
     guac_terminal_buffer_copy_rows(terminal->buffer,
             start_row, end_row, offset);
 
+    /* Clear selection if region is modified */
+    guac_terminal_select_touch(terminal, start_row, 0, end_row,
+            terminal->term_width);
+
     /* Update cursor location if within region */
     if (terminal->visible_cursor_row >= start_row &&
         terminal->visible_cursor_row <= end_row)
@@ -1709,6 +1549,7 @@ void guac_terminal_flush(guac_terminal* terminal) {
         guac_terminal_typescript_flush(terminal->typescript);
 
     /* Flush display state */
+    guac_terminal_select_redraw(terminal);
     guac_terminal_commit_cursor(terminal);
     guac_terminal_display_flush(terminal->display);
     guac_terminal_scrollbar_flush(terminal->scrollbar);
@@ -1906,9 +1747,6 @@ int guac_terminal_send_key(guac_terminal* term, int keysym, int pressed) {
 static int __guac_terminal_send_mouse(guac_terminal* term, guac_user* user,
         int x, int y, int mask) {
 
-    guac_client* client = term->client;
-    guac_socket* socket = client->socket;
-
     /* Determine which buttons were just released and pressed */
     int released_mask =  term->mouse_mask & ~mask;
     int pressed_mask  = ~term->mouse_mask &  mask;
@@ -1944,47 +1782,33 @@ static int __guac_terminal_send_mouse(guac_terminal* term, guac_user* user,
     if ((released_mask & GUAC_CLIENT_MOUSE_RIGHT) || (released_mask & GUAC_CLIENT_MOUSE_MIDDLE))
         return guac_terminal_send_data(term, term->clipboard->buffer, term->clipboard->length);
 
-    /* If text selected, change state based on left mouse mouse button */
+    /* If left mouse button was just released, stop selection */
-    if (term->text_selected) {
+    if (released_mask & GUAC_CLIENT_MOUSE_LEFT)
+        guac_terminal_select_end(term);
 
-        /* If mouse button released, stop selection */
+    /* Update selection state contextually while the left mouse button is
-        if (released_mask & GUAC_CLIENT_MOUSE_LEFT) {
+     * pressed */
+    else if (mask & GUAC_CLIENT_MOUSE_LEFT) {
 
-            int selected_length;
+        int row = y / term->display->char_height - term->scroll_offset;
-
+        int col = x / term->display->char_width;
-            /* End selection and get selected text */
-            int selectable_size = term->term_width * term->term_height * sizeof(char);
-            char* string = malloc(selectable_size);
-            guac_terminal_select_end(term, string);
-
-            selected_length = strnlen(string, selectable_size);
-
-            /* Store new data */
-            guac_common_clipboard_reset(term->clipboard, "text/plain");
-            guac_common_clipboard_append(term->clipboard, string, selected_length);
-            free(string);
-
-            /* Send data */
-            guac_common_clipboard_send(term->clipboard, client);
-            guac_socket_flush(socket);
 
+        /* If mouse button was already just pressed, start a new selection or
+         * resume the existing selection depending on whether shift is held */
+        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);
         }
 
-        /* Otherwise, just update */
+        /* In all other cases, simply update the existing selection as long as
+         * the mouse button is pressed */
         else
-            guac_terminal_select_update(term,
+            guac_terminal_select_update(term, row, col);
-                    y / term->display->char_height - term->scroll_offset,
-                    x / term->display->char_width);
 
     }
 
-    /* Otherwise, if mouse button pressed AND moved, start selection */
-    else if (!(pressed_mask & GUAC_CLIENT_MOUSE_LEFT) &&
-               mask         & GUAC_CLIENT_MOUSE_LEFT)
-        guac_terminal_select_start(term,
-                y / term->display->char_height - term->scroll_offset,
-                x / term->display->char_width);
-
     /* Scroll up if wheel moved up */
     if (released_mask & GUAC_CLIENT_MOUSE_SCROLL_UP)
         guac_terminal_scroll_display_up(term, GUAC_TERMINAL_WHEEL_SCROLL_AMOUNT);

src/terminal/terminal/display.h

@@ -182,17 +182,10 @@ typedef struct guac_terminal_display {
     guac_layer* select_layer;
 
     /**
-     * Whether text is being selected.
+     * Whether text is currently selected.
      */
     bool text_selected;
 
-    /**
-     * Whether the selection is finished, and will no longer be modified. A
-     * committed selection remains highlighted for reference, but the
-     * highlight will be removed when the display changes.
-     */
-    bool selection_committed;
-
     /**
      * The row that the selection starts at.
      */
@@ -333,10 +326,13 @@ void guac_terminal_display_select(guac_terminal_display* display,
         int start_row, int start_col, int end_row, int end_col);
 
 /**
- * Commits the select rectangle, allowing the display to clear it when
+ * Clears the currently-selected region, removing the highlight.
- * necessary.
+ *
+ * @param display
+ *     The guac_terminal_display whose currently-selected region should be
+ *     cleared.
  */
-void guac_terminal_display_commit_select(guac_terminal_display* display);
+void guac_terminal_display_clear_select(guac_terminal_display* display);
 
 #endif
 

src/terminal/terminal/select.h

@@ -0,0 +1,179 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+
+#ifndef GUAC_TERMINAL_SELECT_H
+#define GUAC_TERMINAL_SELECT_H
+
+#include "config.h"
+#include "terminal.h"
+
+#include <stdbool.h>
+
+/**
+ * Forwards the visible portion of the text selection rectangle to the
+ * underlying terminal display, requesting that it be redrawn. If no
+ * visible change would result from redrawing the selection rectangle,
+ * this function may have no effect.
+ *
+ * @param terminal
+ *     The guac_terminal whose text selection rectangle should be
+ *     redrawn.
+ */
+void guac_terminal_select_redraw(guac_terminal* terminal);
+
+/**
+ * Marks the start of text selection at the given row and column. Any existing
+ * selection is cleared. This function should only be invoked while the
+ * guac_terminal is locked through a call to guac_terminal_lock().
+ *
+ * @param terminal
+ *     The guac_terminal instance associated with the text being selected.
+ *
+ * @param row
+ *     The row number of the character at the start of the text selection,
+ *     where the first (top-most) row in the terminal is row 0. Rows within
+ *     the scrollback buffer (above the top-most row of the terminal) will be
+ *     negative.
+ *
+ * @param column
+ *     The column number of the character at the start of the text selection,
+ *     where the first (left-most) column in the terminal is column 0.
+ */
+void guac_terminal_select_start(guac_terminal* terminal, int row, int column);
+
+/**
+ * Updates the end of text selection at the given row and column. This function
+ * should only be invoked while the guac_terminal is locked through a call to
+ * guac_terminal_lock().
+ *
+ * @param terminal
+ *     The guac_terminal instance associated with the text being selected.
+ *
+ * @param row
+ *     The row number of the character at the current end of the text
+ *     selection, where the first (top-most) row in the terminal is row 0. Rows
+ *     within the scrollback buffer (above the top-most row of the terminal)
+ *     will be negative.
+ *
+ * @param column
+ *     The column number of the character at the current end of the text
+ *     selection, where the first (left-most) column in the terminal is
+ *     column 0.
+ */
+void guac_terminal_select_update(guac_terminal* terminal, int row, int column);
+
+/**
+ * Resumes selecting text, expanding the existing selected region from the
+ * closest end to additionally contain the given character. This function
+ * should only be invoked while the guac_terminal is locked through a call to
+ * guac_terminal_lock().
+ *
+ * @param terminal
+ *     The guac_terminal instance associated with the text being selected.
+ *
+ * @param row
+ *     The row number of the character to include within the text selection,
+ *     where the first (top-most) row in the terminal is row 0. Rows within the
+ *     scrollback buffer (above the top-most row of the terminal) will be
+ *     negative.
+ *
+ * @param column
+ *     The column number of the character to include within the text selection,
+ *     where the first (left-most) column in the terminal is column 0.
+ */
+void guac_terminal_select_resume(guac_terminal* terminal, int row, int column);
+
+/**
+ * Ends text selection, removing any highlight and storing the selected
+ * character data within the clipboard associated with the given terminal. If
+ * more text is selected than can fit within the clipboard, text at the end of
+ * the selected area will be dropped as necessary. This function should only be
+ * invoked while the guac_terminal is locked through a call to
+ * guac_terminal_lock().
+ *
+ * @param terminal
+ *     The guac_terminal instance associated with the text being selected.
+ */
+void guac_terminal_select_end(guac_terminal* terminal);
+
+/**
+ * Returns whether at least one character within the given range is currently
+ * selected.
+ *
+ * @param terminal
+ *     The guac_terminal instance associated with the text being selected.
+ *
+ * @param start_row
+ *     The first row of the region to test, inclusive, where the first
+ *     (top-most) row in the terminal is row 0. Rows within the scrollback
+ *     buffer (above the top-most row of the terminal) will be negative.
+ *
+ * @param start_column
+ *     The first column of the region to test, inclusive, where the first
+ *     (left-most) column in the terminal is column 0.
+ *
+ * @param end_row
+ *     The last row of the region to test, inclusive, where the first
+ *     (top-most) row in the terminal is row 0. Rows within the scrollback
+ *     buffer (above the top-most row of the terminal) will be negative.
+ *
+ * @param end_column
+ *     The last column of the region to test, inclusive, where the first
+ *     (left-most) column in the terminal is column 0.
+ *
+ * @return
+ *     true if at least one character within the given range is currently
+ *     selected, false otherwise.
+ */
+bool guac_terminal_select_contains(guac_terminal* terminal,
+        int start_row, int start_column, int end_row, int end_column);
+
+/**
+ * Clears the current selection if it contains at least one character within
+ * the given region. If no text is currently selected, the selection has not
+ * yet been committed, or the region does not contain at least one selected
+ * character, this function has no effect.
+ *
+ * @param terminal
+ *     The guac_terminal instance associated with the text being selected.
+ *
+ * @param start_row
+ *     The first row of the region, inclusive, where the first (top-most) row
+ *     in the terminal is row 0. Rows within the scrollback buffer (above the
+ *     top-most row of the terminal) will be negative.
+ *
+ * @param start_column
+ *     The first column of the region, inclusive, where the first (left-most)
+ *     column in the terminal is column 0.
+ *
+ * @param end_row
+ *     The last row of the region, inclusive, where the first (top-most) row in
+ *     the terminal is row 0. Rows within the scrollback buffer (above the
+ *     top-most row of the terminal) will be negative.
+ *
+ * @param end_column
+ *     The last column of the region, inclusive, where the first (left-most)
+ *     column in the terminal is column 0.
+ */
+void guac_terminal_select_touch(guac_terminal* terminal,
+        int start_row, int start_column, int end_row, int end_column);
+
+#endif
+

src/terminal/terminal/terminal.h

@@ -367,10 +367,18 @@ struct guac_terminal {
     int active_char_set;
 
     /**
-     * Whether text is being selected.
+     * Whether text is currently selected.
      */
     bool text_selected;
 
+    /**
+     * Whether the selection is finished, and will no longer be modified. A
+     * committed selection remains highlighted for reference, but the
+     * highlight will be removed if characters within the selected region are
+     * modified.
+     */
+    bool selection_committed;
+
     /**
      * The row that the selection starts at.
      */
@@ -697,23 +705,6 @@ void guac_terminal_scroll_display_down(guac_terminal* terminal, int amount);
  */
 void guac_terminal_scroll_display_up(guac_terminal* terminal, int amount);
 
-/**
- * Marks the start of text selection at the given row and column.
- */
-void guac_terminal_select_start(guac_terminal* terminal, int row, int column);
-
-/**
- * Updates the end of text selection at the given row and column.
- */
-void guac_terminal_select_update(guac_terminal* terminal, int row, int column);
-
-/**
- * Ends text selection, removing any highlight. Character data is stored in the
- * string buffer provided.
- */
-void guac_terminal_select_end(guac_terminal* terminal, char* string);
-
-
 /* LOW-LEVEL TERMINAL OPERATIONS */