* Add code to detect the system consoles with the help of the

new /proc/consoles files of linux kernel 2.6.38+

doc/Changelog

@@ -1,6 +1,8 @@
 sysvinit (2.89dsf) UNRELEASED; urgency=low
 
   [ Werner Fink ]
+  * Add code to detect the system consoles with the help of the
+    new /proc/consoles files of linux kernel 2.6.38+
   * Try to make utmpdump IPv6 valid, change based on suggestion from
     Navdeep Bhatia (see local bug #32429)
   * Fix signal and alarm handling based on the patch from Florent Viard.

src/Makefile

@@ -134,6 +134,8 @@ halt.o:		halt.c reboot.h
 
 last.o:		last.c oldutmp.h
 
+consoles.o:	consoles.c consoles.h
+
 cleanobjs:
 		rm -f *.o *.bak
 

src/consoles.c

@@ -0,0 +1,109 @@
+/*
+ * consoles.c	    Routines to detect the system consoles
+ *
+ * Copyright (c) 2011 SuSE LINUX Products GmbH, All rights reserved.
+ *
+ * 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, 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 (see the file COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ *
+ * Author: Werner Fink <werner@suse.de>
+ */
+
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <dirent.h>
+#include "consoles.h"
+
+#if !defined(__STDC_VERSION__) || (__STDC_VERSION__ < 199901L)
+# ifndef  typeof
+#  define typeof		__typeof__
+# endif
+# ifndef  restrict
+#  define restrict		__restrict__
+# endif
+#endif
+
+#define alignof(type)		((sizeof(type)+(sizeof(void*)-1)) & ~(sizeof(void*)-1))
+
+struct console *consoles;
+
+static dev_t comparedev;
+static char* scandev(DIR *dir)
+{
+	char *name = (char*)0;
+	struct dirent *dent;
+	int fd;
+
+	fd = dirfd(dir);
+	rewinddir(dir);
+	while ((dent = readdir(dir))) {
+		char path[PATH_MAX];
+		struct stat st;
+		if (fstatat(fd, dent->d_name, &st, 0) < 0)
+			continue;
+		if (!S_ISCHR(st.st_mode))
+			continue;
+		if (comparedev != st.st_rdev)
+			continue;
+		if ((size_t)snprintf(path, sizeof(path), "/dev/%s", dent->d_name) >= sizeof(path))
+			continue;
+		name = realpath(path, NULL);
+		break;
+	}
+	return name;
+}
+
+void detect_consoles(void)
+{
+	FILE *fc;
+	if ((fc = fopen("/proc/consoles", "r"))) {
+		char fbuf[16];
+		int maj, min;
+		DIR *dir;
+		dir = opendir("/dev");
+		if (!dir)
+			goto out;
+		while ((fscanf(fc, "%*s %*s (%[^)]) %d:%d", &fbuf[0], &maj, &min) == 3)) {
+			struct console *restrict tail;
+			char * name;
+
+			if (!strchr(fbuf, 'E'))
+				continue;
+			comparedev = makedev(maj, min);
+			name = scandev(dir);
+
+			if (!name)
+				continue;
+
+			if (posix_memalign((void*)&tail, sizeof(void*), alignof(typeof(struct console))) != 0)
+				perror("memory allocation");
+
+			tail->next = (struct console*)0;
+			tail->tty = name;
+
+			if (!consoles)
+				consoles = tail;
+			else
+				consoles->next = tail;
+		}
+		closedir(dir);
+out:
+		fclose(fc);
+	}
+}

src/consoles.h

@@ -0,0 +1,33 @@
+/*
+ * consoles.h	    Header file for routines to detect the system consoles
+ *
+ * Copyright (c) 2011 SuSE LINUX Products GmbH, All rights reserved.
+ *
+ * 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, 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 (see the file COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ *
+ * Author: Werner Fink <werner@suse.de>
+ */
+
+#include <termios.h>
+
+struct console {
+	char * tty;
+	int tlock;
+	struct termios ltio, otio;
+	struct console *next;
+};
+extern struct console *consoles;
+extern void detect_consoles(void);