Moved from Mate-Extra repository

1 files changed, 285 insertions, 0 deletions

diff --git a/mate-screenshot/screenshot-save.c b/mate-screenshot/screenshot-save.c
new file mode 100644
index 00000000..75e1e457
--- /dev/null
+++ b/mate-screenshot/screenshot-save.c
@@ -0,0 +1,285 @@
+/* screenshot-save.c - image saving functions for MATE Screenshot
+ *
+ * Copyright (C) 2001-2006  Jonathan Blandford <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ */
+
+#include <config.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <signal.h>
+#include <string.h>
+#include <glib/gi18n.h>
+
+#include "screenshot-save.h"
+
+static char *parent_dir = NULL;
+static char *tmp_filename = NULL;
+
+static SaveFunction save_callback = NULL;
+static gpointer save_user_data = NULL;
+
+/* Strategy for saving:
+ *
+ * We keep another process around to handle saving the image.  This is
+ * done for two reasons.  One, the saving takes a non-zero amount of
+ * time (about a quarter of a second on my box.)  This will make it
+ * more interactive.  The second reason is to make the child
+ * responsible for cleaning up the temp dir.  If the parent process is
+ * killed or segfaults, the child process can clean up the temp dir.
+ */
+static void
+clean_up_temporary_dir (gboolean gui_on_error)
+{
+  char *message;
+  gboolean error_occurred = FALSE;
+  if (g_file_test (tmp_filename, G_FILE_TEST_EXISTS))
+    error_occurred = unlink (tmp_filename);
+  if (g_file_test (parent_dir, G_FILE_TEST_EXISTS))
+    error_occurred = rmdir (parent_dir) || error_occurred;
+
+  if (error_occurred)
+    {
+      message = g_strdup_printf (_("Unable to clear the temporary folder:\n%s"),
+				 tmp_filename);
+      if (gui_on_error)
+	{
+	  GtkWidget *dialog;
+
+	  dialog = gtk_message_dialog_new (NULL, 0,
+					   GTK_MESSAGE_ERROR,
+					   GTK_BUTTONS_OK,
+					   "%s", message);
+	  gtk_dialog_run (GTK_DIALOG (dialog));
+	  gtk_widget_destroy (dialog);
+	}
+      else
+	{
+	  g_warning ("%s", message);
+	}
+      g_free (message);
+    }
+  g_free (tmp_filename);
+  g_free (parent_dir);
+}
+
+static void
+child_done_notification (GPid     pid,
+			 gint     status,
+			 gpointer data)
+{
+  /* This should never be called. */
+
+  /* We expect the child to die after the parent.  If the child dies
+   * than it either segfaulted, or was randomly killed.  In either
+   * case, we can't reasonably continue.  */
+  GtkWidget *dialog;
+
+  dialog = gtk_message_dialog_new (NULL, 0,
+				   GTK_MESSAGE_ERROR,
+				   GTK_BUTTONS_OK,
+				   _("The child save process unexpectedly exited.  We are unable to write the screenshot to disk."));
+  gtk_dialog_run (GTK_DIALOG (dialog));
+  gtk_widget_destroy (dialog);
+
+  clean_up_temporary_dir (TRUE);
+
+  exit (1);
+}
+
+static gboolean
+read_pipe_from_child (GIOChannel   *source,
+		      GIOCondition  condition,
+		      gpointer      data)
+{
+  if (condition & G_IO_IN)
+    {
+      gchar *message = NULL;
+      gchar *error_message = NULL;
+      GtkWidget *dialog;
+      GIOStatus status;
+
+      status = g_io_channel_read_line (source, &error_message, NULL, NULL, NULL);
+
+      if (status == G_IO_STATUS_NORMAL)
+	{
+	  message = g_strdup_printf ("Unable to save the screenshot to disk:\n\n%s", error_message);
+	  dialog = gtk_message_dialog_new (NULL, 0,
+					   GTK_MESSAGE_ERROR,
+					   GTK_BUTTONS_OK,
+					   "%s", message);
+	  gtk_dialog_run (GTK_DIALOG (dialog));
+	  gtk_widget_destroy (dialog);
+	  exit (1);
+	}
+    }
+
+  (*save_callback) (save_user_data);
+
+  return FALSE;
+}
+
+static char *
+make_temp_directory (void)
+{
+  gint result, i;
+  gchar *dir_name;
+  
+  i = 0;
+  do
+    {
+      gchar *tmp_dir = g_strdup_printf ("mate-screenshot.%u.%d",
+                                        (unsigned int) getpid (),
+                                        i++);
+      
+      dir_name = g_build_filename (g_get_tmp_dir (),
+                                   tmp_dir,
+                                   NULL);
+      g_free (tmp_dir);
+
+      result = g_mkdir_with_parents (dir_name, 0777);
+      if (result < 0)
+        {
+          g_free (dir_name);
+
+          if (errno != EEXIST)
+            return NULL;
+          else
+            continue;
+        }
+      else
+        return dir_name;
+    }
+  while (TRUE);
+}
+
+static void
+signal_handler (int sig)
+{
+  clean_up_temporary_dir (FALSE);
+
+  signal (sig, SIG_DFL);
+  kill (getpid (), sig);
+}
+
+void
+screenshot_save_start (GdkPixbuf    *pixbuf,
+		       SaveFunction  callback,
+		       gpointer      user_data)
+{
+  GPid pid;
+  int parent_exit_notification[2];
+  int pipe_from_child[2];
+
+  pipe (parent_exit_notification);
+  pipe (pipe_from_child);
+
+  parent_dir = make_temp_directory ();
+  if (parent_dir == NULL)
+    return;
+
+  tmp_filename = g_build_filename (parent_dir,
+		  		   _("Screenshot.png"),
+				   NULL);
+  save_callback = callback;
+  save_user_data = user_data;
+
+  pid = fork ();
+  if (pid == 0)
+    {
+      GError *error = NULL;
+      char c;
+
+      signal (SIGINT, signal_handler);
+      signal (SIGTERM, signal_handler);
+
+      close (parent_exit_notification [1]);
+      close (pipe_from_child [0]);
+
+      if (! gdk_pixbuf_save (pixbuf, tmp_filename,
+			     "png", &error,
+			     "tEXt::Software", "mate-screenshot",
+			     NULL))
+	{
+	  if (error && error->message)
+	    write (pipe_from_child[1],
+		   error->message,
+		   strlen (error->message));
+	  else
+#define ERROR_MESSAGE _("Unknown error saving screenshot to disk")
+	    write (pipe_from_child[1],
+		   ERROR_MESSAGE,
+		   strlen (ERROR_MESSAGE));
+	}
+      /* By closing the pipe, we let the main process know that we're
+       * done saving it. */
+      close (pipe_from_child[1]);
+      read (parent_exit_notification[0], &c, 1);
+
+      clean_up_temporary_dir (FALSE);
+      _exit (0);
+    }
+  else if (pid > 0)
+    {
+      GIOChannel *channel;
+
+      close (parent_exit_notification[0]);
+      close (pipe_from_child[1]);
+
+      channel = g_io_channel_unix_new (pipe_from_child[0]);
+      g_io_add_watch (channel,
+		      G_IO_IN | G_IO_ERR | G_IO_HUP | G_IO_NVAL,
+		      read_pipe_from_child,
+		      NULL);
+      g_io_channel_unref (channel);
+      g_child_watch_add (pid, child_done_notification, NULL);
+    }
+  else
+    /* George awesomely wrote code originally to handle the
+     * could-not-fork case synchronously.  I'm not copying it, as I'm
+     * guessing that the system is pretty hosed if that's the case.
+     * However, he gets major kudos for trying. (-:
+     */
+    g_assert_not_reached ();
+}
+
+const char *
+screenshot_save_get_filename (void)
+{
+  return tmp_filename;
+}
+
+gchar *
+screenshot_sanitize_filename (const char *filename)
+{
+  char *retval, *p;
+
+  g_assert (filename);
+  g_assert (g_utf8_validate (filename, -1, NULL));
+
+  retval = g_uri_escape_string (filename,
+                                "/",
+                                TRUE);
+
+  for (p = retval; *p != '\000'; p = g_utf8_next_char (p))
+    {
+      if (*p == G_DIR_SEPARATOR)
+	*p = '-';
+    }
+
+  return retval;
+}