Add (optional) support for LZ4 PBF compression

Author: joto

CHANGELOG.md

@@ -14,6 +14,9 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 ### Changed
 
 - Various small fixes and cleanups.
+- Now depends on libosmium 2.16.0 or greater. This allows compiling with
+  support for PBF lz4 compression which is enabled by default if the
+  library is found. Disable by setting CMake option WITH_LZ4 to OFF.
 
 ### Fixed
 

CMakeLists.txt

@@ -29,6 +29,8 @@ set(AUTHOR "Jochen Topf <[email protected]>")
 
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
+option(WITH_LZ4 "Build with lz4 support for PBF files" ON)
+
 
 #-----------------------------------------------------------------------------
 #
@@ -38,9 +40,24 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
 include_directories(include)
 
-find_package(Osmium 2.13.1 COMPONENTS io gdal)
+find_package(Osmium 2.16.0 COMPONENTS io gdal)
 include_directories(SYSTEM ${OSMIUM_INCLUDE_DIRS})
 
+if(WITH_LZ4)
+    find_package(LZ4)
+
+    if(LZ4_FOUND)
+        message(STATUS "lz4 library found, compiling with it")
+        add_definitions(-DOSMIUM_WITH_LZ4)
+        include_directories(SYSTEM ${LZ4_INCLUDE_DIRS})
+        list(APPEND OSMIUM_IO_LIBRARIES ${LZ4_LIBRARIES})
+    else()
+        message(WARNING "lz4 library not found, compiling without it")
+    endif()
+else()
+    message(STATUS "Building without lz4 support: Set WITH_LZ4=ON to change this")
+endif()
+
 if(MSVC)
     find_path(GETOPT_INCLUDE_DIR getopt.h)
     find_library(GETOPT_LIBRARY NAMES wingetopt)

README.md

@@ -14,14 +14,21 @@ https://osmcode.org/osmcoastline
 
     https://github.com/osmcode/libosmium
     https://osmcode.org/libosmium
-    At least version 2.13.1 is needed.
+    At least version 2.16.0 is needed.
 
 ### Protozero
 
     https://github.com/mapbox/protozero
     Debian/Ubuntu: libprotozero-dev
     At least version 1.6.1 is needed.
 
+### LZ4 (optional)
+
+    https://lz4.github.io/lz4/
+    Debian/Ubuntu: liblz4-dev
+
+    Only needed for LZ4 PBF compression.
+
 ### zlib (for PBF support)
 
     https://www.zlib.net/

cmake/FindLZ4.cmake

@@ -0,0 +1,38 @@
+find_path(LZ4_INCLUDE_DIR
+  NAMES lz4.h
+  DOC "lz4 include directory")
+mark_as_advanced(LZ4_INCLUDE_DIR)
+find_library(LZ4_LIBRARY
+  NAMES lz4 liblz4
+  DOC "lz4 library")
+mark_as_advanced(LZ4_LIBRARY)
+
+if (LZ4_INCLUDE_DIR)
+  file(STRINGS "${LZ4_INCLUDE_DIR}/lz4.h" _lz4_version_lines
+    REGEX "#define[ \t]+LZ4_VERSION_(MAJOR|MINOR|RELEASE)")
+  string(REGEX REPLACE ".*LZ4_VERSION_MAJOR *\([0-9]*\).*" "\\1" _lz4_version_major "${_lz4_version_lines}")
+  string(REGEX REPLACE ".*LZ4_VERSION_MINOR *\([0-9]*\).*" "\\1" _lz4_version_minor "${_lz4_version_lines}")
+  string(REGEX REPLACE ".*LZ4_VERSION_RELEASE *\([0-9]*\).*" "\\1" _lz4_version_release "${_lz4_version_lines}")
+  set(LZ4_VERSION "${_lz4_version_major}.${_lz4_version_minor}.${_lz4_version_release}")
+  unset(_lz4_version_major)
+  unset(_lz4_version_minor)
+  unset(_lz4_version_release)
+  unset(_lz4_version_lines)
+endif ()
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(LZ4
+  REQUIRED_VARS LZ4_LIBRARY LZ4_INCLUDE_DIR
+  VERSION_VAR LZ4_VERSION)
+
+if (LZ4_FOUND)
+  set(LZ4_INCLUDE_DIRS "${LZ4_INCLUDE_DIR}")
+  set(LZ4_LIBRARIES "${LZ4_LIBRARY}")
+
+  if (NOT TARGET LZ4::LZ4)
+    add_library(LZ4::LZ4 UNKNOWN IMPORTED)
+    set_target_properties(LZ4::LZ4 PROPERTIES
+      IMPORTED_LOCATION "${LZ4_LIBRARY}"
+      INTERFACE_INCLUDE_DIRECTORIES "${LZ4_INCLUDE_DIR}")
+  endif ()
+endif ()

cmake/FindOsmium.cmake

@@ -34,6 +34,7 @@
 #      gdal       - include if you want to use any of the OGR functions
 #      proj       - include if you want to use any of the Proj.4 functions
 #      sparsehash - include if you use the sparsehash index
+#      lz4        - include support for LZ4 compression of PBF files
 #
 #    You can check for success with something like this:
 #
@@ -116,14 +117,21 @@ if(Osmium_USE_PBF)
     find_package(Threads)
     find_package(Protozero 1.6.3)
 
+    if(Osmium_USE_LZ4)
+        find_package(LZ4 REQUIRED)
+        add_definitions(-DOSMIUM_WITH_LZ4)
+    endif()
+
     list(APPEND OSMIUM_EXTRA_FIND_VARS ZLIB_FOUND Threads_FOUND PROTOZERO_INCLUDE_DIR)
     if(ZLIB_FOUND AND Threads_FOUND AND PROTOZERO_FOUND)
         list(APPEND OSMIUM_PBF_LIBRARIES
             ${ZLIB_LIBRARIES}
+            ${LZ4_LIBRARIES}
             ${CMAKE_THREAD_LIBS_INIT}
         )
         list(APPEND OSMIUM_INCLUDE_DIRS
             ${ZLIB_INCLUDE_DIR}
+            ${LZ4_INCLUDE_DIRS}
             ${PROTOZERO_INCLUDE_DIR}
         )
     else()

src/options.cpp

@@ -33,6 +33,8 @@
 #define strcasecmp _stricmp
 #endif
 
+#include <osmium/io/pbf.hpp>
+
 static void print_help() {
     std::cout << "Usage: osmcoastline [OPTIONS] OSMFILE\n"
               << "\nOptions:\n"
@@ -171,7 +173,11 @@ Options::Options(int argc, char* argv[]) {
                 break;
             case 'V':
                 std::cout << "osmcoastline " << get_osmcoastline_long_version() << " / " << get_libosmium_version() << '\n'
-                          << "Copyright (C) 2012-2021  Jochen Topf <[email protected]>\n"
+                          << "PBF compression types:";
+                for (const auto& type : osmium::io::supported_pbf_compression_types()) {
+                    std::cout << " " << type;
+                }
+                std::cout << "\n\nCopyright (C) 2012-2021  Jochen Topf <[email protected]>\n"
                           << "License: GNU GENERAL PUBLIC LICENSE Version 3 <https://gnu.org/licenses/gpl.html>.\n"
                           << "This is free software: you are free to change and redistribute it.\n"
                           << "There is NO WARRANTY, to the extent permitted by law.\n";