/* screenshot-save.c - image saving functions for MATE Screenshot * * Copyright (C) 2001-2006 Jonathan Blandford <jrb@alum.mit.edu> * * 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., 51 Franklin St, Fifth Floor, */ #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; }