From 16fa1e77b29c946f39c961a5c4d7265fd0701d1e Mon Sep 17 00:00:00 2001
From: Wolfgang Scherer <Wolfgang.Scherer@gmx.de>
Date: Thu, 9 Nov 2017 01:16:44 +0100
Subject: [PATCH] [scan] Configuration option to follow symlinks

---
 forked-daapd.conf.in      |  3 +++
 src/conffile.c            |  1 +
 src/library/filescanner.c | 29 ++++++++++++++++++++++++++---
 3 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/forked-daapd.conf.in b/forked-daapd.conf.in
index 41562ff2..62efd456 100644
--- a/forked-daapd.conf.in
+++ b/forked-daapd.conf.in
@@ -62,6 +62,9 @@ library {
 	# Directories to index
 	directories = { "/srv/music" }
 
+	# Follow symlinks. Default: true.	
+#	follow_symlinks = true
+
 	# Directories containing podcasts
 	# For each directory that is indexed the path is matched against these
 	# names. If there is a match all items in the directory are marked as 
diff --git a/src/conffile.c b/src/conffile.c
index 0db89299..dc463dd8 100644
--- a/src/conffile.c
+++ b/src/conffile.c
@@ -73,6 +73,7 @@ static cfg_opt_t sec_library[] =
     CFG_INT("port", 3689, CFGF_NONE),
     CFG_STR("password", NULL, CFGF_NONE),
     CFG_STR_LIST("directories", NULL, CFGF_NONE),
+    CFG_BOOL("follow_symlinks", cfg_true, CFGF_NONE),
     CFG_STR_LIST("podcasts", NULL, CFGF_NONE),
     CFG_STR_LIST("audiobooks", NULL, CFGF_NONE),
     CFG_STR_LIST("compilations", NULL, CFGF_NONE),
diff --git a/src/library/filescanner.c b/src/library/filescanner.c
index 81572f0c..72a7c481 100644
--- a/src/library/filescanner.c
+++ b/src/library/filescanner.c
@@ -679,10 +679,12 @@ create_virtual_path(char *path, char *virtual_path, int virtual_path_len)
  * The return value is 0 if the operation is successful, or -1 on failure
  */
 static int
-read_attributes(char *resolved_path, const char *path, struct stat *sb)
+read_attributes(char *resolved_path, const char *path, struct stat *sb, int *is_link)
 {
   int ret;
 
+  *is_link = 0;
+
   ret = lstat(path, sb);
   if (ret < 0)
     {
@@ -692,6 +694,8 @@ read_attributes(char *resolved_path, const char *path, struct stat *sb)
 
   if (S_ISLNK(sb->st_mode))
     {
+      *is_link = 1;
+
       if (!realpath(path, resolved_path))
         {
 	  DPRINTF(E_LOG, L_SCAN, "Skipping %s, could not dereference symlink: %s\n", path, strerror(errno));
@@ -721,6 +725,8 @@ process_directory(char *path, int parent_id, int flags)
   char entry[PATH_MAX];
   char resolved_path[PATH_MAX];
   struct stat sb;
+  int is_link;
+  int follow_symlinks;
   struct watch_info wi;
   int type;
   char virtual_path[PATH_MAX];
@@ -758,6 +764,8 @@ process_directory(char *path, int parent_id, int flags)
   if (check_speciallib(path, "audiobooks"))
     type |= F_SCAN_TYPE_AUDIOBOOK;
 
+  follow_symlinks = cfg_getbool(cfg_getsec(cfg, "library"), "follow_symlinks");
+
   for (;;)
     {
       if (library_is_exiting())
@@ -786,7 +794,7 @@ process_directory(char *path, int parent_id, int flags)
 	  continue;
 	}
 
-      ret = read_attributes(resolved_path, entry, &sb);
+      ret = read_attributes(resolved_path, entry, &sb, &is_link);
       if (ret < 0)
 	{
 	  DPRINTF(E_LOG, L_SCAN, "Skipping %s, read_attributes() failed\n", entry);
@@ -794,6 +802,12 @@ process_directory(char *path, int parent_id, int flags)
 	  continue;
 	}
 
+      if (is_link && !follow_symlinks)
+        {
+          DPRINTF(E_DBG, L_SCAN, "Ignore symlink %s\n", entry);
+          continue;
+        }
+
       if (S_ISDIR(sb.st_mode))
 	{
 	  push_dir(&dirstack, resolved_path, dir_id);
@@ -1179,6 +1193,7 @@ static void
 process_inotify_file(struct watch_info *wi, char *path, struct inotify_event *ie)
 {
   struct stat sb;
+  int is_link;
   uint32_t path_hash;
   char *file = path;
   char resolved_path[PATH_MAX];
@@ -1306,6 +1321,8 @@ process_inotify_file(struct watch_info *wi, char *path, struct inotify_event *ie
 
   if (ie->mask & IN_CLOSE_WRITE)
     {
+      int follow_symlinks = cfg_getbool(cfg_getsec(cfg, "library"), "follow_symlinks");
+
       DPRINTF(E_DBG, L_SCAN, "File closed: %s\n", path);
 
       // File has been closed so remove from the IN_ATTRIB ignore list
@@ -1317,7 +1334,7 @@ process_inotify_file(struct watch_info *wi, char *path, struct inotify_event *ie
 	    incomingfiles_buffer[i] = 0;
 	  }
 
-      ret = read_attributes(resolved_path, path, &sb);
+      ret = read_attributes(resolved_path, path, &sb, &is_link);
       if (ret < 0)
         {
 	  DPRINTF(E_LOG, L_SCAN, "Skipping %s, read_attributes() failed\n", path);
@@ -1325,6 +1342,12 @@ process_inotify_file(struct watch_info *wi, char *path, struct inotify_event *ie
 	  return;
 	}
 
+      if (is_link && !follow_symlinks)
+        {
+          DPRINTF(E_DBG, L_SCAN, "Ignore symlink %s\n", path);
+          return;
+        }
+
       type = 0;
       if (check_speciallib(path, "compilations"))
 	type |= F_SCAN_TYPE_COMPILATION;