Add FindLeptonica.cmake module to find installed liblept on *nix systems.

Author: egorpugin

CMakeLists.txt

@@ -44,7 +44,7 @@ set(VERSION_MAJOR 3)
 set(VERSION_MINOR 05)
 set(VERSION_PLAIN ${VERSION_MAJOR}.${VERSION_MINOR})
 
-find_package(Leptonica 1.72 REQUIRED)
+find_package(Leptonica 1.71 REQUIRED)
 
 find_package(ICU COMPONENTS uc i18n)
 find_package(PkgConfig QUIET)

cmake/FindLeptonica.cmake

@@ -0,0 +1,49 @@
+#
+# Find Leptonica
+#
+# Exported variables:
+#    Leptonica_FOUND
+#    Leptonica_INCLUDE_DIRS
+#    Leptonica_LIBRARIES
+#
+#    Leptonica_VERSION
+#    Leptonica_MAJOR_VERSION
+#    Leptonica_MINOR_VERSION
+#
+
+find_path(Leptonica_INCLUDE_DIR leptonica/allheaders.h
+    HINTS
+    /usr/include
+    /usr/local/include
+    /opt/include
+    /opt/local/include
+)
+if(NOT Leptonica_INCLUDE_DIR-NOTFOUND)
+    set(Leptonica_INCLUDE_DIRS ${Leptonica_INCLUDE_DIR}/leptonica)
+    file(STRINGS ${Leptonica_INCLUDE_DIRS}/allheaders.h Leptonica_MAJOR_VERSION REGEX "LIBLEPT_MAJOR_VERSION")
+    file(STRINGS ${Leptonica_INCLUDE_DIRS}/allheaders.h Leptonica_MINOR_VERSION REGEX "LIBLEPT_MINOR_VERSION")
+    string(REGEX MATCH "[0-9]+" Leptonica_MAJOR_VERSION ${Leptonica_MAJOR_VERSION})
+    string(REGEX MATCH "[0-9]+" Leptonica_MINOR_VERSION ${Leptonica_MINOR_VERSION})
+    set(Leptonica_VERSION ${Leptonica_MAJOR_VERSION}.${Leptonica_MINOR_VERSION})
+endif()
+
+find_library(Leptonica_LIBRARY NAMES lept liblept
+    HINTS
+    /usr/lib
+    /usr/local/lib
+    /opt/lib
+    /opt/local/lib
+)
+set(Leptonica_LIBRARIES ${Leptonica_LIBRARY})
+
+include(FindPackageHandleStandardArgs)
+
+find_package_handle_standard_args(Leptonica
+    REQUIRED_VARS
+        Leptonica_INCLUDE_DIRS
+        Leptonica_LIBRARIES
+    VERSION_VAR Leptonica_VERSION
+)
+
+mark_as_advanced(Leptonica_INCLUDE_DIRS Leptonica_LIBRARIES)
+