Github action: Modernize/fix CI

This isn't really a useful tool for normal users. It is a demo/example
program for developers to see how the library can be used.

.github/actions/build/action.yml

@@ -19,6 +19,6 @@ runs:
         working-directory: build
 
       - name: Run outline
-        run: build/tools/osmpbf-outline resources/sample.pbf
+        run: build/demo/osmpbf-outline resources/sample.pbf
         shell: bash
 

.github/workflows/c.yml

@@ -3,18 +3,6 @@ name: C CI
 on: [push, pull_request]
 
 jobs:
-  ubuntu20:
-    runs-on: ubuntu-20.04
-    env:
-      CC: gcc
-      CXX: g++
-      CXXFLAGS: -Werror -Wall -pedantic
-      BUILD_TYPE: Debug
-    steps:
-      - uses: actions/checkout@v4
-      - uses: ./.github/actions/install-ubuntu
-      - uses: ./.github/actions/build
-
   ubuntu22:
     runs-on: ubuntu-22.04
     env:
@@ -23,24 +11,48 @@ jobs:
       CXXFLAGS: -Werror -Wall -pedantic
       BUILD_TYPE: Debug
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
       - uses: ./.github/actions/install-ubuntu
       - uses: ./.github/actions/build
 
-  ubuntu22-clang:
-    runs-on: ubuntu-22.04
+  ubuntu24:
+    runs-on: ubuntu-24.04
     env:
-      CC: clang-15
-      CXX: clang++-15
+      CC: gcc
+      CXX: g++
       CXXFLAGS: -Werror -Wall -pedantic
       BUILD_TYPE: Debug
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
       - uses: ./.github/actions/install-ubuntu
       - uses: ./.github/actions/build
 
-  ubuntu22-release:
-    runs-on: ubuntu-22.04
+  ubuntu26:
+    runs-on: ubuntu-26.04
+    env:
+      CC: gcc
+      CXX: g++
+      CXXFLAGS: -Werror -Wall -pedantic
+      BUILD_TYPE: Debug
+    steps:
+      - uses: actions/checkout@v7
+      - uses: ./.github/actions/install-ubuntu
+      - uses: ./.github/actions/build
+
+  ubuntu24-clang:
+    runs-on: ubuntu-24.04
+    env:
+      CC: clang-18
+      CXX: clang++-18
+      CXXFLAGS: -Werror -Wall -pedantic
+      BUILD_TYPE: Debug
+    steps:
+      - uses: actions/checkout@v7
+      - uses: ./.github/actions/install-ubuntu
+      - uses: ./.github/actions/build
+
+  ubuntu24-release:
+    runs-on: ubuntu-24.04
     env:
       CC: gcc
       CXX: g++
@@ -48,7 +60,7 @@ jobs:
       CXXFLAGS: -Werror -Wall -pedantic -Wno-array-bounds
       BUILD_TYPE: Release
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
       - uses: ./.github/actions/install-ubuntu
       - uses: ./.github/actions/build
 
@@ -57,17 +69,17 @@ jobs:
     env:
       CC: clang
       CXX: clang++
-      CXXFLAGS: -Werror -Wall -pedantic
+      CXXFLAGS: -Werror -Wall -pedantic -Wno-nullability-extension
       BUILD_TYPE: Debug
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
       - uses: ./.github/actions/install-macos
       - uses: ./.github/actions/build
 
   windows:
     runs-on: windows-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
       - uses: ./.github/actions/install-windows
       - uses: ./.github/actions/build-windows
 

.github/workflows/java.yml

@@ -3,51 +3,81 @@ name: Java CI
 on: [push, pull_request]
 
 jobs:
-  maven-ubuntu20:
-    runs-on: ubuntu-20.04
-    steps:
-      - uses: actions/checkout@v4
-      - run: sudo apt-get install protobuf-compiler
-      - name: Set up JDK 1.8
-        uses: actions/setup-java@v1
-        with:
-          java-version: 1.8
-      - name: Build with Maven
-        run: mvn -B package --file pom.xml
-
   maven-ubuntu22:
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
       - run: sudo apt-get install protobuf-compiler
-      - name: Set up JDK 1.8
-        uses: actions/setup-java@v1
+      - name: Set up JDK 8
+        uses: actions/setup-java@v5
         with:
-          java-version: 1.8
+          distribution: zulu
+          java-version: 8
       - name: Build with Maven
         run: mvn -B package --file pom.xml
 
-  ant-ubuntu20:
-    runs-on: ubuntu-20.04
+  maven-ubuntu24:
+    runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v4
-      - run: sudo apt-get install protobuf-compiler libprotobuf-java
-      - name: Set up JDK 1.8
-        uses: actions/setup-java@v1
+      - uses: actions/checkout@v7
+      - run: sudo apt-get install protobuf-compiler
+      - name: Set up JDK 8
+        uses: actions/setup-java@v5
         with:
-          java-version: 1.8
-      - name: Build with Ant
-        run: ant
+          distribution: zulu
+          java-version: 8
+      - name: Build with Maven
+        run: mvn -B package --file pom.xml
+
+  maven-ubuntu26:
+    runs-on: ubuntu-26.04
+    steps:
+      - uses: actions/checkout@v7
+      - run: sudo apt-get install protobuf-compiler
+      - name: Set up JDK 8
+        uses: actions/setup-java@v5
+        with:
+          distribution: zulu
+          java-version: 8
+      - name: Build with Maven
+        run: mvn -B package --file pom.xml
 
   ant-ubuntu22:
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
       - run: sudo apt-get install protobuf-compiler libprotobuf-java
-      - name: Set up JDK 1.8
-        uses: actions/setup-java@v1
+      - name: Set up JDK 8
+        uses: actions/setup-java@v5
         with:
-          java-version: 1.8
+          distribution: zulu
+          java-version: 8
+      - name: Build with Ant
+        run: ant
+
+  ant-ubuntu24:
+    runs-on: ubuntu-24.04
+    steps:
+      - uses: actions/checkout@v7
+      - run: sudo apt-get install protobuf-compiler libprotobuf-java
+      - name: Set up JDK 8
+        uses: actions/setup-java@v5
+        with:
+          distribution: zulu
+          java-version: 8
+      - name: Build with Ant
+        run: ant
+
+  ant-ubuntu26:
+    runs-on: ubuntu-26.04
+    steps:
+      - uses: actions/checkout@v7
+      - run: sudo apt-get install protobuf-compiler libprotobuf-java
+      - name: Set up JDK 8
+        uses: actions/setup-java@v5
+        with:
+          distribution: zulu
+          java-version: 8
       - name: Build with Ant
         run: ant
 

CHANGELOG.md

@@ -1,5 +1,21 @@
 ## Unreleased
 
+## Release notes for 1.7.0 (2026-07-26)
+
+- C++: Fix buffer overflow in osmpbf-outline tool [#95](https://github.com/openstreetmap/OSM-binary/pull/95)
+- C++: Various small code cleanups and modernizations
+- C++: osmpbf-outline tool moved to demo directory, it isn't installed by default any more. This tool was never really useful for normal users, it is more a demo/example showing how to use the library
+
+Note to packagers: You should remove the osmpbf-outline tool from packages.
+
+## Release notes for 1.6.1 (2025-12-20)
+
+- Java: Update to latest protoc and protobuf runtime versions [#92](https://github.com/openstreetmap/OSM-binary/pull/92)
+
+## Release notes for 1.6.0 (2024-12-10)
+
+- Java: Update to latest protoc and protobuf runtime versions [#84](https://github.com/openstreetmap/OSM-binary/pull/84)
+
 ## Release notes for 1.5.0 (2021-01-06)
 
 - C: Support hardening buildflags set in the environment ([09845ca4](https://github.com/openstreetmap/OSM-binary/commit/09845ca4087c7404b1de33914233dbf53f9de4c3))

CMakeLists.txt

@@ -1,6 +1,8 @@
-cmake_minimum_required(VERSION 3.7)
+cmake_minimum_required(VERSION 3.10)
 
-project(osmpbf VERSION 1.5.0)
+project(osmpbf VERSION 1.7.0)
+
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
 include(GNUInstallDirs)
 
@@ -18,5 +20,5 @@ add_subdirectory(osmpbf)
 
 # The osmpbf-outline tool does not compile on Windows because getopt.h is missing
 if(NOT MSVC)
-    add_subdirectory(tools)
+    add_subdirectory(demo)
 endif()

README.md

@@ -21,16 +21,17 @@ something more complete see [libosmium](https://osmcode.org/libosmium/).
 
 ### Building with Maven
 
-We publish the Java library to [Maven Central](https://search.maven.org/):
+We publish the Java library to [Maven Central](https://mvnrepository.com/artifact/org.openstreetmap.pbf/osmpbf): ![Maven Central](https://img.shields.io/maven-central/v/org.openstreetmap.pbf/osmpbf.svg)
 
 ```xml
 <dependency>
   <groupId>org.openstreetmap.pbf</groupId>
   <artifactId>osmpbf</artifactId>
-  <version>1.5.0</version>
+  <version>${LATEST_VERSION}</version>
 </dependency>
 ```
 
+
 To build the Java library run:
 
 ```sh
@@ -69,11 +70,11 @@ To install:
 make install
 ```
 
-There is a tool named osmpbf-outline that shows a debug output of the contents
-of a PBF file. To run it:
+There is a demo tool named osmpbf-outline that shows a debug output of some of
+the contents of a PBF file. To run it:
 
 ```sh
-tools/osmpbf-outline osm-file.osm.pbf
+demo/osmpbf-outline osm-file.osm.pbf
 ```
 
 

build.xml

@@ -21,7 +21,7 @@
 		<exec executable="/bin/sh">
 			<arg value="./build.sh"/>
 		</exec>
-		<javac includeantruntime="false" destdir="${build.dir}">
+		<javac includeantruntime="false" destdir="${build.dir}" source="1.8" target="1.8">
 			<src path="${src.dir}"/>
 			<src path="${src.generated.dir}"/>
 			<classpath>

demo/CMakeLists.txt

@@ -12,5 +12,5 @@ target_include_directories(osmpbf-outline SYSTEM PRIVATE ${ZLIB_INCLUDE_DIR})
 target_link_libraries(osmpbf-outline PRIVATE osmpbf ZLIB::ZLIB protobuf::libprotobuf)
 set_property(TARGET osmpbf-outline PROPERTY CXX_STANDARD 11)
 
-install(TARGETS osmpbf-outline RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
-install(FILES osmpbf-outline.1 DESTINATION ${CMAKE_INSTALL_MANDIR}/man1)
+#install(TARGETS osmpbf-outline RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+#install(FILES osmpbf-outline.1 DESTINATION ${CMAKE_INSTALL_MANDIR}/man1)

demo/osmpbf-outline.cpp

@@ -2,10 +2,10 @@
 #include <unistd.h>
 
 // used for va_list in debug-print methods
-#include <stdarg.h>
+#include <cstdarg>
 
 // file io lib
-#include <stdio.h>
+#include <cstdio>
 
 // getopt is used to check for the --color-flag
 #include <getopt.h>
@@ -23,47 +23,31 @@
 // this is the header to pbf format
 #include <osmpbf/osmpbf.h>
 
+namespace {
+
 // should the output use color?
 bool usecolor = false;
 
-// buffer for reading a compressed blob from file
-char buffer[OSMPBF::max_uncompressed_blob_size];
-
-// buffer for decompressing the blob
-char unpack_buffer[OSMPBF::max_uncompressed_blob_size];
-
-// pbf struct of a BlobHeader
-OSMPBF::BlobHeader blobheader;
-
-// pbf struct of a Blob
-OSMPBF::Blob blob;
-
-// pbf struct of an OSM HeaderBlock
-OSMPBF::HeaderBlock headerblock;
-
-// pbf struct of an OSM PrimitiveBlock
-OSMPBF::PrimitiveBlock primblock;
-
 // prints a formatted message to stdout, optionally color coded
 void msg(const char* format, int color, va_list args) {
     if (usecolor) {
-        fprintf(stdout, "\x1b[0;%dm", color);
+        std::fprintf(stdout, "\x1b[0;%dm", color);
     }
-    vfprintf(stdout, format, args);
+    std::vfprintf(stdout, format, args);
     if (usecolor) {
-        fprintf(stdout, "\x1b[0m\n");
+        std::fprintf(stdout, "\x1b[0m\n");
     } else {
-        fprintf(stdout, "\n");
+        std::fprintf(stdout, "\n");
     }
 }
 
 // prints a formatted message to stdout, color coded to red
-void err(const char* format, ...) {
+[[noreturn]] void err(const char* format, ...) {
     va_list args;
     va_start(args, format);
     msg(format, 31, args);
     va_end(args);
-    exit(1);
+    std::exit(1);
 }
 
 // prints a formatted message to stdout, color coded to yellow
@@ -90,23 +74,25 @@ void debug(const char* format, ...) {
     va_end(args);
 }
 
+} // anonymous namespace
+
 // application main method
 int main(int argc, char *argv[]) {
     // check if the output is a tty so we can use colors
 
 #ifdef WIN32
-    usecolor = 0;
+    usecolor = false;
 #else
     usecolor = isatty(1);
 #endif
 
-    static struct option long_options[] = {
-        {"color", no_argument, 0, 'c'},
-        {0, 0, 0, 0}
+    option const long_options[] = {
+        {"color", no_argument, nullptr, 'c'},
+        {nullptr, 0, nullptr, 0}
     };
 
-    while (1) {
-        int c = getopt_long(argc, argv, "c", long_options, 0);
+    while (true) {
+        int const c = getopt_long(argc, argv, "c", long_options, nullptr);
 
         if (c == -1) {
             break;
@@ -117,7 +103,7 @@ int main(int argc, char *argv[]) {
                 usecolor = true;
                 break;
             default:
-                exit(1);
+                return 1;
         }
     }
 
@@ -127,19 +113,25 @@ int main(int argc, char *argv[]) {
     }
 
     // open specified file
-    FILE *fp = fopen(argv[optind], "rb");
+    FILE *fp = std::fopen(argv[optind], "rb");
 
     if (!fp) {
         err("can't open file '%s'", argv[optind]);
     }
 
+    // buffer for reading a compressed blob from file
+    static char buffer[OSMPBF::max_uncompressed_blob_size];
+
+    // buffer for decompressing the blob
+    static char unpack_buffer[OSMPBF::max_uncompressed_blob_size];
+
     // read while the file has not reached its end
-    while (!feof(fp)) {
+    while (!std::feof(fp)) {
         // storage of size, used multiple times
-        int32_t sz;
+        std::uint32_t sz = 0;
 
         // read the first 4 bytes of the file, this is the size of the blob-header
-        if (fread(&sz, sizeof(sz), 1, fp) != 1) {
+        if (std::fread(&sz, sizeof(sz), 1, fp) != 1) {
             break; // end of file reached
         }
 
@@ -152,12 +144,15 @@ int main(int argc, char *argv[]) {
         }
 
         // read the blob-header from the file
-        if (fread(buffer, sz, 1, fp) != 1) {
+        if (std::fread(buffer, sz, 1, fp) != 1) {
             err("unable to read blob-header from file");
         }
 
+        // pbf struct of a BlobHeader
+        OSMPBF::BlobHeader blobheader;
+
         // parse the blob-header from the read-buffer
-        if (!blobheader.ParseFromArray(buffer, sz)) {
+        if (!blobheader.ParseFromArray(buffer, static_cast<int>(sz))) {
             err("unable to parse blob header");
         }
 
@@ -180,12 +175,15 @@ int main(int argc, char *argv[]) {
         }
 
         // read the blob from the file
-        if (fread(buffer, sz, 1, fp) != 1) {
+        if (std::fread(buffer, sz, 1, fp) != 1) {
             err("unable to read blob from file");
         }
 
+        // pbf struct of a Blob
+        OSMPBF::Blob blob;
+
         // parse the blob from the read-buffer
-        if (!blob.ParseFromArray(buffer, sz)) {
+        if (!blob.ParseFromArray(buffer, static_cast<int>(sz))) {
             err("unable to parse blob");
         }
 
@@ -204,15 +202,15 @@ int main(int argc, char *argv[]) {
             sz = blob.raw().size();
 
             // check that raw_size is set correctly
-            if (sz != blob.raw_size()) {
-                warn("  reports wrong raw_size: %u bytes", blob.raw_size());
+            if (sz != static_cast<std::uint32_t>(blob.raw_size())) {
+                warn("  reports wrong raw_size: %d bytes", blob.raw_size());
             }
 
             // tell about the blob-data
             debug("  contains uncompressed data: %u bytes", sz);
 
             // copy the uncompressed data over to the unpack_buffer
-            memcpy(unpack_buffer, buffer, sz);
+            std::memcpy(unpack_buffer, buffer, sz);
         }
 
         // if the blob has zlib-compressed data
@@ -232,6 +230,12 @@ int main(int argc, char *argv[]) {
             debug("  contains zlib-compressed data: %u bytes", sz);
             debug("  uncompressed size: %u bytes", blob.raw_size());
 
+            // ensure the raw_size fits into the unpack_buffer, otherwise
+            // zlib would inflate past the end of the fixed-size buffer
+            if (blob.raw_size() < 0 || blob.raw_size() > OSMPBF::max_uncompressed_blob_size) {
+                err("  raw_size is bigger then allowed (%d > %u)", blob.raw_size(), OSMPBF::max_uncompressed_blob_size);
+            }
+
             // zlib information
             z_stream z;
 
@@ -273,9 +277,6 @@ int main(int argc, char *argv[]) {
                 warn("  contains several data streams");
             }
 
-            // we have at least one datastream
-            found_data = true;
-
             // tell about the compressed data
             debug("  contains lzma-compressed data: %u bytes", blob.lzma_data().size());
             debug("  uncompressed size: %u bytes", blob.raw_size());
@@ -284,6 +285,36 @@ int main(int argc, char *argv[]) {
             err("  lzma-decompression is not supported");
         }
 
+        // if the blob has lz4-compressed data
+        if (blob.has_lz4_data()) {
+            // issue a warning if there is more than one data steam, a blob may only contain one data stream
+            if (found_data) {
+                warn("  contains several data streams");
+            }
+
+            // tell about the compressed data
+            debug("  contains lz4-compressed data: %u bytes", blob.lz4_data().size());
+            debug("  uncompressed size: %u bytes", blob.raw_size());
+
+            // issue a warning, lz4 compression is not yet supported
+            err("  lz4-decompression is not supported");
+        }
+
+        // if the blob has zstd-compressed data
+        if (blob.has_zstd_data()) {
+            // issue a warning if there is more than one data steam, a blob may only contain one data stream
+            if (found_data) {
+                warn("  contains several data streams");
+            }
+
+            // tell about the compressed data
+            debug("  contains zstd-compressed data: %u bytes", blob.zstd_data().size());
+            debug("  uncompressed size: %u bytes", blob.raw_size());
+
+            // issue a warning, zstd compression is not yet supported
+            err("  zstd-decompression is not supported");
+        }
+
         // check we have at least one data-stream
         if (!found_data) {
             err("  does not contain any known data stream");
@@ -294,28 +325,31 @@ int main(int argc, char *argv[]) {
             // tell about the OSMHeader blob
             info("  OSMHeader");
 
+            // pbf struct of an OSM HeaderBlock
+            OSMPBF::HeaderBlock headerblock;
+
             // parse the HeaderBlock from the blob
-            if (!headerblock.ParseFromArray(unpack_buffer, sz)) {
+            if (!headerblock.ParseFromArray(unpack_buffer, static_cast<int>(sz))) {
                 err("unable to parse header block");
             }
 
             // tell about the bbox
             if (headerblock.has_bbox()) {
-                OSMPBF::HeaderBBox bbox = headerblock.bbox();
+                OSMPBF::HeaderBBox const& bbox = headerblock.bbox();
                 debug("    bbox: %.7f,%.7f,%.7f,%.7f",
-                    (double)bbox.left() / OSMPBF::lonlat_resolution,
-                    (double)bbox.bottom() / OSMPBF::lonlat_resolution,
-                    (double)bbox.right() / OSMPBF::lonlat_resolution,
-                    (double)bbox.top() / OSMPBF::lonlat_resolution);
+                    static_cast<double>(bbox.left()) / OSMPBF::lonlat_resolution,
+                    static_cast<double>(bbox.bottom()) / OSMPBF::lonlat_resolution,
+                    static_cast<double>(bbox.right()) / OSMPBF::lonlat_resolution,
+                    static_cast<double>(bbox.top()) / OSMPBF::lonlat_resolution);
             }
 
             // tell about the required features
-            for (int i = 0, l = headerblock.required_features_size(); i < l; i++) {
+            for (int i = 0, l = headerblock.required_features_size(); i < l; ++i) {
                 debug("    required_feature: %s", headerblock.required_features(i).c_str());
             }
 
             // tell about the optional features
-            for (int i = 0, l = headerblock.optional_features_size(); i < l; i++) {
+            for (int i = 0, l = headerblock.optional_features_size(); i < l; ++i) {
                 debug("    optional_feature: %s", headerblock.optional_features(i).c_str());
             }
 
@@ -332,8 +366,11 @@ int main(int argc, char *argv[]) {
             // tell about the OSMData blob
             info("  OSMData");
 
+            // pbf struct of an OSM PrimitiveBlock
+            OSMPBF::PrimitiveBlock primblock;
+
             // parse the PrimitiveBlock from the blob
-            if (!primblock.ParseFromArray(unpack_buffer, sz)) {
+            if (!primblock.ParseFromArray(unpack_buffer, static_cast<int>(sz))) {
                 err("unable to parse primitive block");
             }
 
@@ -350,11 +387,11 @@ int main(int argc, char *argv[]) {
             debug("    primitivegroups: %u groups", primblock.primitivegroup_size());
 
             // iterate over all PrimitiveGroups
-            for (int i = 0, l = primblock.primitivegroup_size(); i < l; i++) {
+            for (int i = 0, l = primblock.primitivegroup_size(); i < l; ++i) {
                 // one PrimitiveGroup from the the Block
-                OSMPBF::PrimitiveGroup pg = primblock.primitivegroup(i);
+                OSMPBF::PrimitiveGroup const& pg = primblock.primitivegroup(i);
 
-                bool found_items=false;
+                bool found_items = false;
 
                 // tell about nodes
                 if (pg.nodes_size() > 0) {
@@ -409,7 +446,7 @@ int main(int argc, char *argv[]) {
     }
 
     // close the file pointer
-    fclose(fp);
+    std::fclose(fp);
 
     // clean up the protobuf lib
     google::protobuf::ShutdownProtobufLibrary();

include/osmpbf/osmpbf.h

@@ -18,7 +18,7 @@
 // this describes the high-level OSM objects
 #include <osmpbf/osmformat.pb.h> // IWYU pragma: export
 
-#define OSMPBF_VERSION "1.5.0"
+#define OSMPBF_VERSION "1.7.0"
 
 namespace OSMPBF {
 

osmpbf/fileformat.proto

@@ -65,5 +65,3 @@ message BlobHeader {
   optional bytes indexdata = 2;
   required int32 datasize = 3;
 }
-
-

osmpbf/osmformat.proto

@@ -260,4 +260,3 @@ message Relation {
   repeated sint64 memids = 9 [packed = true]; // DELTA encoded
   repeated MemberType types = 10 [packed = true];
 }
-

pom.xml

@@ -6,7 +6,7 @@
   <groupId>org.openstreetmap.pbf</groupId>
   <artifactId>osmpbf</artifactId>
   <packaging>jar</packaging>
-  <version>1.5.0</version>
+  <version>1.7.0</version>
   <name>OSM-Binary</name>
   <description>Library for the OpenStreetMap PBF format</description>
   <url>https://github.com/openstreetmap/OSM-binary</url>
@@ -31,9 +31,20 @@
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <protobuf.version>4.33.2</protobuf.version>
   </properties>
 
   <build>
+    <extensions>
+      <!-- makes build variables like os.detected.classifier available.
+           use to select the correct protoc instance for the OS.
+           see protobuf-maven-plugin below -->
+      <extension>
+        <groupId>kr.motd.maven</groupId>
+        <artifactId>os-maven-plugin</artifactId>
+        <version>1.7.1</version>
+      </extension>
+    </extensions>
     <sourceDirectory>${basedir}/src.java</sourceDirectory>
     <testSourceDirectory>${basedir}/test.java</testSourceDirectory>
 
@@ -59,7 +70,7 @@
         <artifactId>protobuf-maven-plugin</artifactId>
         <version>0.6.1</version>
         <configuration>
-          <protocExecutable>protoc</protocExecutable>
+          <protocArtifact>com.google.protobuf:protoc:${protobuf.version}:exe:${os.detected.classifier}</protocArtifact>
         </configuration>
         <executions>
           <execution>
@@ -122,16 +133,19 @@
           </execution>
         </executions>
       </plugin>
+      <plugin>
+        <groupId>org.sonatype.central</groupId>
+        <artifactId>central-publishing-maven-plugin</artifactId>
+        <version>0.6.0</version>
+        <extensions>true</extensions>
+        <configuration>
+          <publishingServerId>central</publishingServerId>
+          <autoPublish>true</autoPublish>
+        </configuration>
+      </plugin>
     </plugins>
   </build>
 
-  <pluginRepositories>
-    <pluginRepository>
-      <id>dtrott</id>
-      <url>http://maven.davidtrott.com/repository</url>
-    </pluginRepository>
-  </pluginRepositories>
-
   <dependencies>
     <dependency>
       <groupId>junit</groupId>
@@ -143,19 +157,8 @@
     <dependency>
       <groupId>com.google.protobuf</groupId>
       <artifactId>protobuf-java</artifactId>
-      <version>3.16.3</version>
+      <version>${protobuf.version}</version>
     </dependency>
   </dependencies>
 
-  <distributionManagement>
-    <repository>
-      <id>ossrh</id>
-      <url>https://oss.sonatype.org/service/local/staging/deploy/maven2</url>
-    </repository>
-    <snapshotRepository>
-      <id>ossrh</id>
-      <url>https://oss.sonatype.org/content/repositories/snapshots</url>
-    </snapshotRepository>
-  </distributionManagement>
-
 </project>