/*
* $Log$
+ * Revision 1.9 2008/02/15 23:52:12 james
+ * *** empty log message ***
+ *
+ * Revision 1.8 2008/02/15 20:52:36 james
+ * *** empty log message ***
+ *
+ * Revision 1.7 2008/02/15 19:51:30 james
+ * *** empty log message ***
+ *
+ * Revision 1.6 2008/02/15 19:09:00 james
+ * *** empty log message ***
+ *
+ * Revision 1.5 2008/02/15 18:26:49 james
+ * *** empty log message ***
+ *
+ * Revision 1.4 2008/02/15 18:16:48 james
+ * *** empty log message ***
+ *
+ * Revision 1.3 2008/02/15 18:16:35 james
+ * *** empty log message ***
+ *
+ * Revision 1.2 2008/02/15 16:48:56 james
+ * *** empty log message ***
+ *
* Revision 1.1 2008/02/15 15:09:17 james
* *** empty log message ***
*
*/
+#define LOCK_ASCII
+#undef LOCK_BINARY
+
+#define STALE_CHECK_INTERVAL 10
+
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <malloc.h>
+#include <unistd.h>
+#include <string.h>
+#include <strings.h>
+#include <stdlib.h>
+#include <pwd.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <errno.h>
+#include <time.h>
+#include <sys/time.h>
+
+#include "lockfile.h"
+
+Filelist *
+filelist_new (void)
+{
+ Filelist *fl = (Filelist *) malloc (sizeof (Filelist));
+
+ fl->head = NULL;
+
+ return fl;
+}
+
+void
+filelist_remove (Filelist * fl, Filelist_ent * fle)
+{
+ Filelist_ent **ep;
+
+ for (ep = &fl->head; *ep; ep = &((*ep)->next))
+ if (fle == *ep)
+ break;
+
+
+ if (!*ep)
+ return;
+
+ *ep = fle->next;
+
+ free (fle);
+}
+
+void
+filelist_add (Filelist * fl, char *fn)
+{
+ Filelist_ent *fle;
+ int i = strlen (fn);
+
+ if (i >= FILE_LIST_MAX_LEN)
+ return;
+
+ for (fle = fl->head; fle; fle = fle->next)
+ if (!strcmp (fle->name, fn))
+ return;
+
+ fle = malloc (sizeof (Filelist_ent));
+
+ strcpy (fle->name, fn);
+
+ fle->next = fl->head;
+ fl->head = fle;
+}
+
+void
+filelist_free (Filelist * fl)
+{
+ while (fl->head)
+ filelist_remove (fl, fl->head);
+ free (fl);
+}
+
+void
+filelist_print (Filelist * fl, FILE * f)
+{
+ Filelist_ent *fle;
+ if (!fl)
+ {
+ fprintf (f, "(empty list)\n");
+ return;
+ }
+ for (fle = fl->head; fle; fle = fle->next)
+ fprintf (f, "%s\n", fle->name);
+}
+
+
+
+
+static int
+chown_uucp (fd)
+ int fd;
+{
+ static int uuid = -1, ugid;
+ struct passwd *pw;
+
+ if (uuid < 0)
+ {
+ if (pw = getpwnam ("uucp"))
+ {
+ uuid = pw->pw_uid;
+ ugid = pw->pw_gid;
+ }
+ else
+ {
+ return -1;
+ }
+ }
+ return fchown (fd, uuid, ugid);
+}
+
+int
+lockfile_make (char *name)
+{
+ char buf[1024], tmpfn[1024];
+ char *ptr;
+ int fd;
+ int i;
+
+ strcpy (tmpfn, name);
+
+ ptr = rindex (tmpfn, '/');
+ if (!ptr)
+ return -1;
+
+ ptr++;
+
+ ptr += sprintf (ptr, "LTMP.%d", getpid ());
+ *ptr = 0;
+
+ i = sprintf (buf, "%10d\n", getpid ());
+
+ unlink (tmpfn);
+ fd = open (tmpfn, O_WRONLY | O_CREAT | O_TRUNC, 0444);
+ if (fd < 0)
+ {
+ unlink (tmpfn);
+ return -1;
+ }
+
+ write (fd, buf, i);
+ fchmod (fd, 044);
+ if (chown_uucp (fd))
+ {
+ close (fd);
+ unlink (tmpfn);
+ return -1;
+ }
+
+ close (fd);
+
+ if (link (tmpfn, name) < 0)
+ {
+ unlink (tmpfn);
+ return -1;
+ }
+
+ unlink (tmpfn);
+ return 0;
+}
+
+
+void
+lockfile_add_places (Filelist * fl, char *leaf)
+{
+ char buf[1024];
+ struct stat stbuf;
+ char *lock_dirs[] =
+ { "/var/lock/uucp", "/var/spool/lock", "/var/spool/uucp", "/etc/locks",
+ "/usr/spool/uucp", "/var/spool/locks", "/usr/spool/lock",
+ "/usr/spool/locks", "/usr/spool/uucp/LCK", "/var/lock"
+ };
+ int i;
+
+ for (i = 0; i < (sizeof (lock_dirs) / sizeof (char *)); ++i)
+ {
+ if (stat (lock_dirs[i], &stbuf))
+ continue;
+ strcpy (buf, lock_dirs[i]);
+ strcat (buf, "/");
+ strcat (buf, leaf);
+ filelist_add (fl, buf);
+ }
+}
+
+
+static void
+do_tedious_mangling (Filelist * fl, char *buf, char *ptr, char inv, int lower)
+{
+ while (*ptr)
+ {
+ if (lower && (*ptr >= 'A') && (*ptr <= 'Z'))
+ *ptr |= 32;
+ if (*ptr == '/')
+ *ptr = inv;
+ ptr++;
+ }
+
+ lockfile_add_places (fl, buf);
+}
+
+
+void
+lockfile_regularize_and_add (Filelist * fl, char *leaf)
+{
+ char buf[1024] = "LCK..";
+ char *ptr;
+
+ if (*leaf == '/')
+ leaf++;
+
+ ptr = buf;
+ while (*ptr)
+ ptr++;
+
+ strcpy (ptr, leaf);
+ do_tedious_mangling (fl, buf, ptr, '_', 0);
+ strcpy (ptr, leaf);
+ do_tedious_mangling (fl, buf, ptr, '_', 1);
+ strcpy (ptr, leaf);
+ do_tedious_mangling (fl, buf, ptr, '.', 0);
+ strcpy (ptr, leaf);
+ do_tedious_mangling (fl, buf, ptr, '.', 1);
+}
+
+void
+lockfile_add_name_from_path (Filelist * fl, char *file)
+{
+ char *ptr = file;
+
+
+ if (*ptr == '/')
+ ptr++;
+ lockfile_regularize_and_add (fl, ptr);
+
+ if (!strncmp (ptr, "dev/", 4))
+ {
+ ptr += 4;
+ lockfile_regularize_and_add (fl, ptr);
+ }
+
+}
+
+void
+lockfile_add_name_from_dev (Filelist * fl, dev_t dev)
+{
+ char buf[1024];
+ sprintf (buf, "LCK.%03d.%03d", major (dev), minor (dev));
+ lockfile_add_places (fl, buf);
+}
+
+void
+lockfile_check_dir_for_dev (Filelist * fl, char *dir, dev_t dev)
+{
+ char buf[1024];
+ struct stat ent_stat;
+ struct dirent *de;
+ DIR *d;
+
+ d = opendir (dir);
+
+ if (!d)
+ return;
+
+ while ((de = readdir (d)))
+ {
+ strcpy (buf, dir);
+ strcat (buf, de->d_name);
+
+ if (stat (buf, &ent_stat))
+ continue;
+ if (!S_ISCHR (ent_stat.st_mode))
+ continue;
+ if (ent_stat.st_rdev != dev)
+ continue;
+
+ lockfile_add_name_from_path (fl, buf);
+
+ }
+ closedir (d);
+}
+
+Filelist *
+lockfile_make_list (char *device)
+{
+ struct stat dev_stat;
+ Filelist *ret = NULL;
+
+
+ if (stat (device, &dev_stat))
+ return ret;
+ if (!S_ISCHR (dev_stat.st_mode))
+ return ret;
+
+ ret = filelist_new ();
+
+ lockfile_add_name_from_dev (ret, dev_stat.st_rdev);
+
+ lockfile_add_name_from_path (ret, device);
+
+ lockfile_check_dir_for_dev (ret, "/dev/", dev_stat.st_rdev);
+ lockfile_check_dir_for_dev (ret, "/dev/usb/", dev_stat.st_rdev);
+ lockfile_check_dir_for_dev (ret, "/dev/tts/", dev_stat.st_rdev);
+
+ return ret;
+}
+
+static void
+remove_stale_lock (char *path)
+{
+ int fd;
+ int pid;
+ char apid[20];
+ int length;
+
+ fd = open (path, O_RDONLY);
+ if (fd < 0)
+ return;
+
+ length = read (fd, apid, sizeof (apid) - 1);
+ if (length < 0)
+ length = 0;
+ apid[length] = 0;
+
+ pid = 0;
+ if (length == sizeof (pid) || sscanf (apid, "%d", &pid) != 1 || pid == 0)
+ {
+ pid = *((int *) apid);
+#ifdef LOCK_ASCII
+ fprintf (stderr,
+ "compiled with ascii locks, found binary lock file (length=%d, pid=%d)!",
+ length, pid);
+#endif
+ }
+#ifdef LOCK_BINARY
+ else
+ {
+ fprintf (stderr,
+ "compiled with binary locks, found ascii lock file (length=%d, pid=%d)!",
+ length, pid);
+ }
+#endif
+
+ close (fd);
+
+ if ((kill (pid, 0) < 0) && (errno == ESRCH))
+ {
+ fprintf (stderr, "removing stale lock file %s\n", path);
+ unlink (path);
+ }
+
+}
+
+void
+lockfile_remove_stale (Filelist * fl)
+{
+ Filelist_ent *fle;
+ struct stat buf;
+
+ for (fle = fl->head; fle; fle = fle->next)
+ {
+ if (stat (fle->name, &buf))
+ continue;
+ remove_stale_lock (fle->name);
+ }
+
+
+}
+
+
+Filelist *
+lockfile_lock (Filelist * fl)
+{
+ Filelist *ret;
+ Filelist_ent *fle;
+
+ ret = filelist_new ();
+
+ lockfile_remove_stale (fl);
+
+ for (fle = fl->head; fle; fle = fle->next)
+ {
+ if (lockfile_make (fle->name))
+ {
+ fprintf (stderr, "Failed to get lockfile %s\n", fle->name);
+ filelist_free (ret);
+ return NULL;
+ }
+ filelist_add (ret, fle->name);
+ }
+
+ return ret;
+}
+
+void
+lockfile_unlock (Filelist * fl)
+{
+
+ while (fl->head)
+ {
+ unlink (fl->head->name);
+ filelist_remove (fl, fl->head);
+ }
+}
+
+
+/* If we have a passive lock, check noone has an */
+/* active one, returns 1 if he does, 0 if he doesnt */
+int
+serial_lock_check (Serial_lock * l)
+{
+ Filelist_ent *fle;
+ int locks_found = 0;
+ struct stat buf;
+ struct timeval now, dif;
+
+ if (l->mode == SERIAL_LOCK_ACTIVE)
+ return 0;
+
+ for (fle = l->locks_to_check->head; fle; fle = fle->next)
+ {
+ if (!stat (fle->name, &buf))
+ locks_found++;
+ }
+
+ if (!locks_found)
+ return 0;
+
+ gettimeofday (&now, NULL);
+ timersub (&now, &l->last_stale_purge, &dif);
+
+ if (dif.tv_sec > STALE_CHECK_INTERVAL)
+ {
+ lockfile_remove_stale (l->locks_to_check);
+ l->last_stale_purge = now;
+ }
+
+ return 1;
+}
+
+void
+serial_lock_free (Serial_lock * l)
+{
+ if (!l)
+ return;
+
+ if (l->locks_held)
+ {
+ lockfile_unlock (l->locks_held);
+ filelist_free (l->locks_held);
+ }
+
+ if (l->locks_to_check)
+ {
+ filelist_free (l->locks_to_check);
+ }
+
+ free (l);
+}
+
+
+Serial_lock *
+serial_lock_new (char *dev, int mode)
+{
+ Filelist *fl = lockfile_make_list (dev);
+ Serial_lock *l;
+
+ if (!fl)
+ return NULL;
+
+ l = (Serial_lock *) malloc (sizeof (Serial_lock));
+
+ l->mode = mode;
+ l->locks_to_check = fl;
+ l->locks_held = NULL;
+ memset (&l->last_stale_purge, 0, sizeof (l->last_stale_purge));
+
+ if (mode == SERIAL_LOCK_PASSIVE)
+ return l;
+
+ l->locks_held = lockfile_lock (l->locks_to_check);
+ if (!l->locks_held)
+ {
+ serial_lock_free (l);
+ return NULL;
+ }
+
+ return l;
+}
+
+
+#if 0
+int
+main (int argc, char *argv[])
+{
+ Filelist *fl = lockfile_make_list ("/dev/ttyS0");
+ Filelist *fll;
+ Filelist_ent *fle;
+
+ filelist_print (fl, stdout);
+
+ fll = lockfile_lock (fl);
+
+ filelist_print (fll, stdout);
+}
+#endif
~ianmdlvl / sympathy.git / blobdiff