3 fixes for Cygwin

The attached patch fixes three issues of fuser on Cygwin.:

- Cygwin does not support /proc/net/unix. The call to fill_unix_cache
  always generates an error message that /proc/net/unix couldn't be
  found, so the patch disables the call for Cygwin. An alternative
  fix would be to avoid the error message entirely.

- `ls /dev' on Cygwin only lists manually added entries to /dev, not the
  default files suported by Cygwin internally. Also,
  /proc/$PID/mountinfo doesn't exist up to Cygwin 1.7.11. This
  breaks fuser when using the _LISTS_H option.

- If you don't include lists.h, the code in check_dir doesn't work well.
  st.st_ino is never set to 0, so the timeout(stat, ...) is never
  called. Also, thedev never gets a valid value in this case, but it's
  used subsequently for comparisons.

3 files changed, 9 insertions, 3 deletions

diff --git a/ChangeLog b/ChangeLog
index 36b68fb..1ac7dec 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -12,6 +12,7 @@ Changes in 22.17 (unreleased)
 	* fuser is not compiled on hurd-i386 Debian #673485
 	* No TEXTRELS in src/lists built as PIE on x86
 	* Fake pstree root for kernels with hidepid turned on
+	* More fixes for Cygwin SF Patch #3511920
 
 Changes in 22.16
 ================
diff --git a/src/fuser.c b/src/fuser.c
index 5a09cf2..27cb934 100644
--- a/src/fuser.c
+++ b/src/fuser.c
@@ -265,7 +265,7 @@ scan_procs(struct names *names_head, struct inode_list *ino_head,
 		if (root_stat) free(root_stat);
 		if (cwd_stat)  free(cwd_stat);
 		if (exe_stat)  free(exe_stat);
-#ifndef __linux__
+#if !defined (__linux__) && !defined (__CYGWIN__)
 		check_dir(pid, "lib", dev_head, ino_head, uid, ACCESS_MMAP,
 			  sockets, netdev);
 		check_dir(pid, "mmap", dev_head, ino_head, uid, ACCESS_MMAP,
@@ -932,7 +932,9 @@ int main(int argc, char *argv[])
 #endif
 
 	netdev = find_net_dev();
+#ifndef __CYGWIN__	/* Cygwin doesn't support /proc/net/unix */
 	fill_unix_cache(&unixsockets);
+#endif
 
     for (argc_cnt = 1; argc_cnt < argc; argc_cnt++) {
       current_argv = argv[argc_cnt];
@@ -1375,7 +1377,7 @@ check_dir(const pid_t pid, const char *dirname, struct device_list *dev_head,
 		st.st_ino = 0;
 		if ((thedev = device(filepath)) < 0)
 #else
-		if (!st.st_ino && timeout(stat, filepath, &st, 5) != 0)
+		if (timeout(stat, filepath, &st, 5) != 0)
 #endif
 		{
             if (errno != ENOENT) {
@@ -1383,6 +1385,9 @@ check_dir(const pid_t pid, const char *dirname, struct device_list *dev_head,
 				    filepath, strerror(errno));
             }
 		} else {
+#ifndef _LISTS_H
+			thedev = st.st_dev;
+#endif
 			if (thedev == netdev) {
 				for (sock_tmp = sockets; sock_tmp != NULL;
 				     sock_tmp = sock_tmp->next) {
diff --git a/src/fuser.h b/src/fuser.h
index 21eb720..242ce19 100644
--- a/src/fuser.h
+++ b/src/fuser.h
@@ -86,7 +86,7 @@ struct mount_list {
 	struct mount_list *next;
 };
 
-#if defined (__GNUC__) && defined(__OPTIMIZE__)
+#if defined (__GNUC__) && defined(__OPTIMIZE__) && !defined (__CYGWIN__)
 # include "lists.h"
 typedef struct mntinfo_s {
     list_t   this;