configure.ac: Fallback to jpeglib.h detection when no .pc is provided

dd09caa5 · Hugo Beauzée-Luyssen · 499eae6a · dd09caa5
Commit dd09caa5 authored Jun 22, 2018 by Hugo Beauzée-Luyssen
--- a/configure.ac
+++ b/configure.ac
@@ -302,6 +302,12 @@ PKG_CHECK_MODULES(SQLITE, sqlite3)
 PKG_CHECK_MODULES(LIBJPEG, libjpeg, [
     have_libjpeg="yes"
     AC_DEFINE(HAVE_JPEG, 1, [Define to 1 if libjpeg is available])
+ ], [
+dnl Falling back to libjpeg.h based detection
+    AC_CHECK_HEADERS(jpeglib.h, [
+        have_libjpeg="yes"
+        AC_SUBST(LIBJPEG_LIBS, "-ljpeg")
+    ])
 ])
 AM_CONDITIONAL([HAVE_LIBJPEG], [test "${have_libjpeg}" = "yes"])