initial import from bash_3.1dfsg-8.diff.gzupstream

1 files changed, 267 insertions, 0 deletions

diff --git a/debian/clear_console.c b/debian/clear_console.c
new file mode 100644
index 0000000..8412827
--- /dev/null
+++ b/debian/clear_console.c
@@ -0,0 +1,267 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <string.h>
+#include <getopt.h>
+#include <errno.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#if defined(__linux)
+#include <linux/kd.h>
+#include <linux/vt.h>
+#elif defined(__FreeBSD_kernel__)
+#include <sys/consio.h>
+#include <sys/kbio.h>
+#endif
+
+#include <curses.h>
+#include <term.h>
+
+#define VERSION "0.1"
+
+char* progname;
+int quiet = 0;
+
+void usage()
+{
+  fprintf(stderr, "Usage: %s [option]\n", progname);
+  fprintf(stderr, "valid options are:\n");
+  fprintf(stderr, "\t-q  --quiet    don't print error messages\n");
+  fprintf(stderr, "\t-h --help      display this help text and exit\n");
+  fprintf(stderr, "\t-V --version   display version information and exit\n");
+}
+
+const struct option opts[] =
+{
+  /* operations */
+    {"help", no_argument, 0, 'h'},
+    {"version", no_argument, 0, 'V'},
+    {"quiet", no_argument, 0, 'q'},
+    {0, 0, 0, 0}
+};
+
+static int putch(int c)
+{
+        return putchar(c);
+}
+
+
+/* taken from console-utils, lib/misc-console-utils.c */
+
+int is_a_console(int fd)
+{
+#if defined(__linux__)
+  char arg;
+#elif defined(__FreeBSD_kernel__)
+  int arg;
+#endif
+
+  arg = 0;
+  return (ioctl(fd, KDGKBTYPE, &arg) == 0
+          && ((arg == KB_OTHER) || (arg == KB_101) || (arg == KB_84)));
+}
+
+static int open_a_console(char *fnam)
+{
+  int fd;
+
+  /* try read-only */
+  fd = open(fnam, O_RDWR);
+
+  /* if failed, try read-only */
+  if (fd < 0 && errno == EACCES)
+      fd = open(fnam, O_RDONLY);
+
+  /* if failed, try write-only */
+  if (fd < 0 && errno == EACCES)
+      fd = open(fnam, O_WRONLY);
+
+  /* if failed, fail */
+  if (fd < 0)
+      return -1;
+
+  /* if not a console, fail */
+  if (! is_a_console(fd))
+    {
+      close(fd);
+      return -1;
+    }
+
+  /* success */
+  return fd;
+}
+
+/*
+ * Get an fd for use with kbd/console ioctls.
+ * We try several things because opening /dev/console will fail
+ * if someone else used X (which does a chown on /dev/console).
+ *
+ * if tty_name is non-NULL, try this one instead.
+ */
+
+int get_console_fd(char* tty_name)
+{
+  int fd;
+
+  if (tty_name)
+    {
+      if (-1 == (fd = open_a_console(tty_name)))
+        return -1;
+      else
+        return fd;
+    }
+
+  fd = open_a_console("/dev/tty");
+  if (fd >= 0)
+    return fd;
+
+  fd = open_a_console("/dev/tty0");
+  if (fd >= 0)
+    return fd;
+
+  fd = open_a_console("/dev/console");
+  if (fd >= 0)
+    return fd;
+
+  for (fd = 0; fd < 3; fd++)
+    if (is_a_console(fd))
+      return fd;
+
+#if 0
+  fprintf(stderr,
+          _("Couldnt get a file descriptor referring to the console\n"));
+#endif
+  return -1;            /* total failure */
+}
+
+
+int is_pseudo_tty(int fd)
+{
+  char *tty = ttyname(fd);
+
+  if (!strncmp(tty, "/dev/pts/", 9))
+    return 1;
+
+  if (!strncmp(tty, "/dev/tty", 8) && tty[8] >= 'a' && tty[8] <= 'z')
+    return 1;
+
+  return 0;
+}
+
+int clear_console(int fd)
+{
+  int num, tmp_num;
+#if defined(__linux__)
+  struct vt_stat vtstat;
+#endif
+
+  /* clear screen */
+  setupterm((char *) 0, 1, (int *) 0);
+  if (tputs(clear_screen, lines > 0 ? lines : 1, putch) == ERR)
+    {
+      exit(1);
+    }
+
+  if (is_pseudo_tty(STDIN_FILENO))
+    return 0;
+
+  if (!strcmp(getenv("TERM"), "screen"))
+      return 0;
+
+  /* get current vt */
+#if defined(__linux__)
+  if (ioctl(fd, VT_GETSTATE, &vtstat) < 0)
+#elif defined(__FreeBSD_kernel__)
+  if (ioctl(fd, VT_ACTIVATE, &num) < 0)
+#endif
+    {
+      if (!quiet)
+	fprintf(stderr, "%s: cannot get VTstate\n", progname);
+      exit(1);
+    }
+#if defined(__linux__)
+  num = vtstat.v_active;
+#endif
+  tmp_num = (num == 1 ? 2 : 1);
+
+  /* switch vt to clear the scrollback buffer */
+  if (ioctl(fd, VT_ACTIVATE, tmp_num))
+    {
+      if (!quiet)
+	perror("chvt: VT_ACTIVATE");
+      exit(1);
+    }
+
+  if (ioctl(fd, VT_WAITACTIVE, tmp_num))
+    {
+      if (!quiet)
+	perror("VT_WAITACTIVE");
+      exit(1);
+    }
+
+  /* switch back */
+  if (ioctl(fd, VT_ACTIVATE, num))
+    {
+      if (!quiet)
+	perror("chvt: VT_ACTIVATE");
+      exit(1);
+    }
+
+  if (ioctl(fd, VT_WAITACTIVE, num))
+    {
+      if (!quiet)
+	perror("VT_WAITACTIVE");
+      exit(1);
+    }
+}
+
+int main (int argc, char* argv[])
+{
+  int fd;
+  int result;                          /* option handling */
+  int an_option;
+
+  if ((progname = strrchr(argv[0], '/')) == NULL)
+    progname = argv[0];
+  else
+    progname++;
+
+  while (1)
+    {
+      result = getopt_long(argc, argv, "Vhq", opts, &an_option);
+      
+      if (result == EOF)
+	break;
+
+      switch (result)
+        {
+        case 'V':
+	  fprintf(stdout, "%s: Version %s\n", progname, VERSION);
+          exit (0);
+        case 'h':
+          usage();
+          exit (0);
+	  
+        case 'q':
+          quiet = 1;
+        }
+    }
+
+  if (optind < argc)
+    {
+      if (!quiet)
+	fprintf(stderr, "%s: no non-option arguments are valid", progname);
+      exit(1);
+    }
+
+  if ((fd = get_console_fd(NULL)) == -1)
+    {
+      if (!quiet)
+	fprintf(stderr, "%s: terminal is not a console\n", progname);
+      exit(1);
+    }
+
+  clear_console(fd);
+
+  return 0;
+}