Update to 2.74submit/tizen/20160407.062043accepted/tizen/wearable/20160407.111603accepted/tizen/tv/20160407.111550accepted/tizen/mobile/20160407.111534accepted/tizen/ivi/20160407.111623accepted/tizen/common/20160407.132919

Change-Id: Ic7e94612466be7786c3d2b0724d745c7720e01c9
Signed-off-by: Seonah Moon <seonah1.moon@samsung.com>

1 files changed, 288 insertions, 0 deletions

diff --git a/src/inotify.c b/src/inotify.c
new file mode 100644
index 0000000..52d412f
--- /dev/null
+++ b/src/inotify.c
@@ -0,0 +1,288 @@
+/* dnsmasq is Copyright (c) 2000-2015 Simon Kelley
+ 
+   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; version 2 dated June, 1991, or
+   (at your option) version 3 dated 29 June, 2007.
+ 
+   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, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "dnsmasq.h"
+#ifdef HAVE_INOTIFY
+
+#include <sys/inotify.h>
+#include <sys/param.h> /* For MAXSYMLINKS */
+
+/* the strategy is to set a inotify on the directories containing
+   resolv files, for any files in the directory which are close-write 
+   or moved into the directory.
+   
+   When either of those happen, we look to see if the file involved
+   is actually a resolv-file, and if so, call poll-resolv with
+   the "force" argument, to ensure it's read.
+
+   This adds one new error condition: the directories containing
+   all specified resolv-files must exist at start-up, even if the actual
+   files don't. 
+*/
+
+static char *inotify_buffer;
+#define INOTIFY_SZ (sizeof(struct inotify_event) + NAME_MAX + 1)
+
+/* If path is a symbolic link, return the path it
+   points to, made absolute if relative.
+   If path doesn't exist or is not a symlink, return NULL.
+   Return value is malloc'ed */
+static char *my_readlink(char *path)
+{
+  ssize_t rc, size = 64;
+  char *buf;
+
+  while (1)
+    {
+      buf = safe_malloc(size);
+      rc = readlink(path, buf, (size_t)size);
+      
+      if (rc == -1)
+	{
+	  /* Not link or doesn't exist. */
+	  if (errno == EINVAL || errno == ENOENT)
+	    return NULL;
+	  else
+	    die(_("cannot access path %s: %s"), path, EC_MISC);
+	}
+      else if (rc < size-1)
+	{
+	  char *d;
+	  
+	  buf[rc] = 0;
+	  if (buf[0] != '/' && ((d = strrchr(path, '/'))))
+	    {
+	      /* Add path to relative link */
+	      char *new_buf = safe_malloc((d - path) + strlen(buf) + 2);
+	      *(d+1) = 0;
+	      strcpy(new_buf, path);
+	      strcat(new_buf, buf);
+	      free(buf);
+	      buf = new_buf;
+	    }
+	  return buf;
+	}
+
+      /* Buffer too small, increase and retry */
+      size += 64;
+      free(buf);
+    }
+}
+
+void inotify_dnsmasq_init()
+{
+  struct resolvc *res;
+  inotify_buffer = safe_malloc(INOTIFY_SZ);
+  daemon->inotifyfd = inotify_init1(IN_NONBLOCK | IN_CLOEXEC);
+  
+  if (daemon->inotifyfd == -1)
+    die(_("failed to create inotify: %s"), NULL, EC_MISC);
+  
+  for (res = daemon->resolv_files; res; res = res->next)
+    {
+      char *d, *new_path, *path = safe_malloc(strlen(res->name) + 1);
+      int links = MAXSYMLINKS;
+
+      strcpy(path, res->name);
+
+      /* Follow symlinks until we reach a non-symlink, or a non-existant file. */
+      while ((new_path = my_readlink(path)))
+	{
+	  if (links-- == 0)
+	    die(_("too many symlinks following %s"), res->name, EC_MISC);
+	  free(path);
+	  path = new_path;
+	}
+
+      res->wd = -1;
+
+      if ((d = strrchr(path, '/')))
+	{
+	  *d = 0; /* make path just directory */
+	  res->wd = inotify_add_watch(daemon->inotifyfd, path, IN_CLOSE_WRITE | IN_MOVED_TO);
+
+	  res->file = d+1; /* pointer to filename */
+	  *d = '/';
+	  
+	  if (res->wd == -1 && errno == ENOENT)
+	    die(_("directory %s for resolv-file is missing, cannot poll"), res->name, EC_MISC);
+	}	  
+	 
+      if (res->wd == -1)
+	die(_("failed to create inotify for %s: %s"), res->name, EC_MISC);
+	
+    }
+}
+
+
+/* initialisation for dynamic-dir. Set inotify watch for each directory, and read pre-existing files */
+void set_dynamic_inotify(int flag, int total_size, struct crec **rhash, int revhashsz)
+{
+  struct hostsfile *ah;
+  
+  for (ah = daemon->dynamic_dirs; ah; ah = ah->next)
+    {
+      DIR *dir_stream = NULL;
+      struct dirent *ent;
+      struct stat buf;
+     
+      if (!(ah->flags & flag))
+	continue;
+ 
+      if (stat(ah->fname, &buf) == -1 || !(S_ISDIR(buf.st_mode)))
+	{
+	  my_syslog(LOG_ERR, _("bad dynamic directory %s: %s"), 
+		    ah->fname, strerror(errno));
+	  continue;
+	}
+      
+       if (!(ah->flags & AH_WD_DONE))
+	 {
+	   ah->wd = inotify_add_watch(daemon->inotifyfd, ah->fname, IN_CLOSE_WRITE | IN_MOVED_TO);
+	   ah->flags |= AH_WD_DONE;
+	 }
+
+       /* Read contents of dir _after_ calling add_watch, in the hope of avoiding
+	  a race which misses files being added as we start */
+       if (ah->wd == -1 || !(dir_stream = opendir(ah->fname)))
+	 {
+	   my_syslog(LOG_ERR, _("failed to create inotify for %s: %s"),
+		     ah->fname, strerror(errno));
+	   continue;
+	 }
+
+       while ((ent = readdir(dir_stream)))
+	 {
+	   size_t lendir = strlen(ah->fname);
+	   size_t lenfile = strlen(ent->d_name);
+	   char *path;
+	   
+	   /* ignore emacs backups and dotfiles */
+	   if (lenfile == 0 || 
+	       ent->d_name[lenfile - 1] == '~' ||
+	       (ent->d_name[0] == '#' && ent->d_name[lenfile - 1] == '#') ||
+	       ent->d_name[0] == '.')
+	     continue;
+	   
+	   if ((path = whine_malloc(lendir + lenfile + 2)))
+	     {
+	       strcpy(path, ah->fname);
+	       strcat(path, "/");
+	       strcat(path, ent->d_name);
+	       
+	       /* ignore non-regular files */
+	       if (stat(path, &buf) != -1 && S_ISREG(buf.st_mode))
+		 {
+		   if (ah->flags & AH_HOSTS)
+		     total_size = read_hostsfile(path, ah->index, total_size, rhash, revhashsz);
+#ifdef HAVE_DHCP
+		   else if (ah->flags & (AH_DHCP_HST | AH_DHCP_OPT))
+		     option_read_dynfile(path, ah->flags);
+#endif		   
+		 }
+
+	       free(path);
+	     }
+	 }
+    }
+}
+
+int inotify_check(time_t now)
+{
+  int hit = 0;
+  struct hostsfile *ah;
+
+  while (1)
+    {
+      int rc;
+      char *p;
+      struct resolvc *res;
+      struct inotify_event *in;
+
+      while ((rc = read(daemon->inotifyfd, inotify_buffer, INOTIFY_SZ)) == -1 && errno == EINTR);
+      
+      if (rc <= 0)
+	break;
+      
+      for (p = inotify_buffer; rc - (p - inotify_buffer) >= (int)sizeof(struct inotify_event); p += sizeof(struct inotify_event) + in->len) 
+	{
+	  in = (struct inotify_event*)p;
+	  
+	  for (res = daemon->resolv_files; res; res = res->next)
+	    if (res->wd == in->wd && in->len != 0 && strcmp(res->file, in->name) == 0)
+	      hit = 1;
+
+	  /* ignore emacs backups and dotfiles */
+	  if (in->len == 0 || 
+	      in->name[in->len - 1] == '~' ||
+	      (in->name[0] == '#' && in->name[in->len - 1] == '#') ||
+	      in->name[0] == '.')
+	    continue;
+	  
+	  for (ah = daemon->dynamic_dirs; ah; ah = ah->next)
+	    if (ah->wd == in->wd)
+	      {
+		size_t lendir = strlen(ah->fname);
+		char *path;
+		
+		if ((path = whine_malloc(lendir + in->len + 2)))
+		  {
+		    strcpy(path, ah->fname);
+		    strcat(path, "/");
+		    strcat(path, in->name);
+		     
+		    my_syslog(LOG_INFO, _("inotify, new or changed file %s"), path);
+
+		    if (ah->flags & AH_HOSTS)
+		      {
+			read_hostsfile(path, ah->index, 0, NULL, 0);
+#ifdef HAVE_DHCP
+			if (daemon->dhcp || daemon->doing_dhcp6) 
+			  {
+			    /* Propogate the consequences of loading a new dhcp-host */
+			    dhcp_update_configs(daemon->dhcp_conf);
+			    lease_update_from_configs(); 
+			    lease_update_file(now); 
+			    lease_update_dns(1);
+			  }
+#endif
+		      }
+#ifdef HAVE_DHCP
+		    else if (ah->flags & AH_DHCP_HST)
+		      {
+			if (option_read_dynfile(path, AH_DHCP_HST))
+			  {
+			    /* Propogate the consequences of loading a new dhcp-host */
+			    dhcp_update_configs(daemon->dhcp_conf);
+			    lease_update_from_configs(); 
+			    lease_update_file(now); 
+			    lease_update_dns(1);
+			  }
+		      }
+		    else if (ah->flags & AH_DHCP_OPT)
+		      option_read_dynfile(path, AH_DHCP_OPT);
+#endif
+		    
+		    free(path);
+		  }
+	      }
+	}
+    }
+  return hit;
+}
+
+#endif  /* INOTIFY */
+