Changed environment variable AVATAR_DIR to LIBRAVATARSERV_DIR to avoid collisions.

AVATAR_DIR is still supported until 1.0.0 for backwards-compatibility.

CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required (VERSION 3.2)
 project(libravatarserv
-        VERSION 0.3.0
+        VERSION 0.3.1
         LANGUAGES CXX
 )
 

README.md

@@ -42,7 +42,7 @@ HTTPS.
 
 libravatarserv looks in each of `${XDG_DATA_DIRS}` for a directory named
 `libravatarserv`. You can force a different directory by setting the environment
-variable `${AVATAR_DIR}`.
+variable `${LIBRAVATARSERV_DIR}` (until 0.3.0 `${AVATAR_DIR}`).
 
 The image files are named like your email address, no file extension. If you
 want to deliver a default image for unknown email addresses, name it `default`.

src/libravatarserv.cpp

@@ -83,17 +83,16 @@ int main()
 
 bool find_avatar_dir()
 {
-    const char *envdir = std::getenv("AVATAR_DIR");
-    if (envdir != nullptr)
+    const char *envdir = std::getenv("LIBRAVATARSERV_DIR");
+    if (envdir == nullptr)
     {
-        if (fs::is_directory(envdir))
-        {
-            avatar_dir = envdir;
-        }
-        else
-        {
-            return false;
-        }
+        // TODO: Remove AVATAR_DIR in 1.0.0
+        // DEPRECATED because it is potentially used by another program
+        envdir = std::getenv("AVATAR_DIR");
+    }
+    if (envdir != nullptr && fs::is_directory(envdir))
+    {
+        avatar_dir = envdir;
     }
     else
     {