libstagefright_foundation_defaults: Add host support

Test: Build libstagefright_foundation
Bug: 151789258

Change-Id: If357f8e4041e67daae8546c968c54a6059e959a9
diff --git a/media/libstagefright/foundation/ALooperRoster.cpp b/media/libstagefright/foundation/ALooperRoster.cpp
index 8a7c3eb..0a4e598 100644
--- a/media/libstagefright/foundation/ALooperRoster.cpp
+++ b/media/libstagefright/foundation/ALooperRoster.cpp
@@ -166,7 +166,7 @@
         }
         s.append("\n");
     }
-    write(fd, s.string(), s.size());
+    (void)write(fd, s.string(), s.size());
 }
 
 }  // namespace android
diff --git a/media/libstagefright/foundation/AString.cpp b/media/libstagefright/foundation/AString.cpp
index 4bd186c..8722e14 100644
--- a/media/libstagefright/foundation/AString.cpp
+++ b/media/libstagefright/foundation/AString.cpp
@@ -387,10 +387,14 @@
     va_start(ap, format);
 
     char *buffer;
-    vasprintf(&buffer, format, ap);
+    int bufferSize = vasprintf(&buffer, format, ap);
 
     va_end(ap);
 
+    if(bufferSize < 0) {
+        return AString();
+    }
+
     AString result(buffer);
 
     free(buffer);
diff --git a/media/libstagefright/foundation/Android.bp b/media/libstagefright/foundation/Android.bp
index 682758a..87ebd00 100644
--- a/media/libstagefright/foundation/Android.bp
+++ b/media/libstagefright/foundation/Android.bp
@@ -11,6 +11,7 @@
     vndk: {
         enabled: true,
     },
+    host_supported: true,
     double_loadable: true,
     include_dirs: [
         "frameworks/av/include",
@@ -84,6 +85,9 @@
                 "-DNO_IMEMORY",
             ],
         },
+        darwin: {
+            enabled: false,
+        },
     },
 
     clang: true,