json: replace json-c with vendored nlohmann/json (closes #2366)

.github/workflows/centos-and-fedora.yml

@@ -420,10 +420,6 @@ jobs:
           wget https://github.com/Kitware/CMake/releases/download/v3.12.0/cmake-3.12.0-Linux-x86_64.sh -O cmake/cmake.sh
           sudo sh cmake/cmake.sh --skip-license --prefix=/usr/local
 
-# el8, el9, fr35, fr36 provide json-c-devel (version 12+)
-      - name: Setup json-c
-        run: sudo yum -y install json-c-devel
-
       - name: Run packaging tests
         run:  |
           chmod +x ci/tests/pk-tests.sh

.github/workflows/codeql.yml

@@ -32,7 +32,7 @@ jobs:
         if: ${{ matrix.language == 'cpp' }}
         run: |
           sudo apt-get update
-          sudo apt-get install --yes libbz2-dev libjson-c-dev libgtest-dev
+          sudo apt-get install --yes libbz2-dev libgtest-dev
 
       - name: After Prepare (cpp)
         if: ${{ matrix.language == 'cpp' }}

.github/workflows/coverity.yml

@@ -17,7 +17,7 @@ jobs:
         run: |
           apt-get -y update
           apt-get -y install git bash build-essential autoconf automake clang cmake \
-                     zlib1g-dev libbz2-dev libjson-c-dev libbotan-3-dev asciidoctor curl
+                     zlib1g-dev libbz2-dev libbotan-3-dev asciidoctor curl
 
       - name: Checkout
         uses: actions/checkout@v7

.github/workflows/lint.yml

@@ -28,6 +28,7 @@ jobs:
       - uses: DoozyX/clang-format-lint-action@v0.20
         with:
           clangFormatVersion: 11.1.0
+          exclude: './src/lib/nlohmann'
   shellcheck:
     runs-on: ubuntu-latest
     steps:

.github/workflows/ubuntu.yml

@@ -121,7 +121,7 @@ jobs:
 #     Already installed on GHA: build-essential libbz2-dev zlib1g-dev
         run: |
           sudo apt-get -y update
-          sudo apt-get -y install cmake libbz2-dev libjson-c-dev ${{ matrix.backend.package }} asciidoctor
+          sudo apt-get -y install cmake libbz2-dev ${{ matrix.backend.package }} asciidoctor
 
       - name: Configure
         run: |
@@ -155,7 +155,7 @@ jobs:
       - name: Install dependencies
         run: |
           sudo apt-get -y update
-          sudo apt-get -y install cmake libbz2-dev libjson-c-dev libbotan-2-dev asciidoctor googletest
+          sudo apt-get -y install cmake libbz2-dev libbotan-2-dev asciidoctor googletest
 
       - name: Configure
         run: |
@@ -196,7 +196,7 @@ jobs:
       - name: Install dependencies
         run: |
           sudo apt-get -y update
-          sudo apt-get -y install cmake libbz2-dev libjson-c-dev libbotan-2-dev asciidoctor googletest
+          sudo apt-get -y install cmake libbz2-dev libbotan-2-dev asciidoctor googletest
 
       - name: Build googletest
         run: |
@@ -243,7 +243,7 @@ jobs:
       - name: Install dependencies
         run: |
           sudo apt-get -y update
-          sudo apt-get -y install cmake libbz2-dev libjson-c-dev libbotan-2-dev asciidoctor
+          sudo apt-get -y install cmake libbz2-dev libbotan-2-dev asciidoctor
 
       - name: Checkout sexpp
         uses: actions/checkout@v7
@@ -308,7 +308,7 @@ jobs:
       - name: Install dependencies
         run: |
           sudo apt-get -y update
-          sudo apt-get -y install cmake libbz2-dev libjson-c-dev libbotan-2-dev asciidoctor
+          sudo apt-get -y install cmake libbz2-dev libbotan-2-dev asciidoctor
 
       - name: Configure
         run: |
@@ -345,7 +345,7 @@ jobs:
       - name: Install dependencies
         run: |
           sudo apt-get -y update
-          sudo apt-get -y install cmake libbz2-dev libjson-c-dev libbotan-2-dev asciidoctor
+          sudo apt-get -y install cmake libbz2-dev libbotan-2-dev asciidoctor
 
       - name: Download source package
         uses: actions/download-artifact@v8

.github/workflows/windows-msys2.yml

@@ -107,7 +107,7 @@ jobs:
             toolchain:p
             cmake:p
             ${{ matrix.backend.lib }}:p
-            json-c:p
+
             asciidoctor:p
             gtest:p
           path-type: minimal

.github/workflows/windows-native.yml

@@ -170,7 +170,7 @@ jobs:
           export SystemDrive="$SYSTEMDRIVE"
           export SystemRoot="$SYSTEMROOT"
           export windir="$WINDIR"          
-          vcpkg install --triplet ${{ matrix.arch.triplet }} bzip2 zlib json-c getopt dirent ${{ matrix.backend }}
+          vcpkg install --triplet ${{ matrix.arch.triplet }} bzip2 zlib getopt dirent ${{ matrix.backend }}
 
       - name: Upload vcpkg logs on failure
         if: failure()

CMakeLists.txt

@@ -59,6 +59,11 @@ option(ENABLE_SANITIZERS "Enable ASan and other sanitizers.")
 option(ENABLE_FUZZERS "Enable fuzz targets.")
 option(DOWNLOAD_GTEST "Download Googletest" On)
 option(SYSTEM_LIBSEXPP "Use system sexpp library" OFF)
+# nlohmann/json is vendored as a single-header under src/lib/nlohmann/ — see
+# JSON_VENDORED below. This option is kept for documentation only; if set to
+# ON it would let a downstream consumer override the vendored copy via
+# find_package(nlohmann_json), but the project itself always vendors.
+set(JSON_VENDORED ON CACHE BOOL "Use vendored nlohmann/json (single-header under src/lib/nlohmann/)" FORCE)
 
 # crypto components
 function(tristate_feature_auto NAME DESCRIPTION)
@@ -250,6 +255,11 @@ else (SYSTEM_LIBSEXPP)
   set(SEXPP_TARGET sexpp)
 endif (SYSTEM_LIBSEXPP)
 
+# nlohmann/json is vendored as a single-header under src/lib/nlohmann/.
+# json-utils.h does `#include <nlohmann/json.hpp>`; src/lib/CMakeLists.txt
+# adds src/lib/nlohmann to the include path. No external dependency, no
+# FetchContent, no install rules.
+
 add_subdirectory(src/lib)
 add_subdirectory(src/rnp)
 add_subdirectory(src/rnpkeys)

_typos.toml

@@ -17,6 +17,8 @@ ede3 = "ede3"
 ffrom = "ffrom"
 clen = "clen"
 __THW_INTEL__ = "__THW_INTEL__"
+unexpect_eof = "unexpect_eof"
+unexpect_char = "unexpect_char"
 
 [default.extend-words]
 MERCHANTIBILITY = "MERCHANTIBILITY"
@@ -33,5 +35,6 @@ extend-exclude = [
     "src/tests/data/**",
     "src/libsexpp/**",
     # Generated roff (ci/regen-man-pages.sh); lint the .adoc sources instead
-    "docs/man/**"
+    "docs/man/**",
+    "src/lib/nlohmann/**"
 ]

ci/tests/downstream-consumer.sh

@@ -47,7 +47,7 @@ RNP_ROOT="$( cd "$DIR0"/../.. && pwd )"
 #   CRYPTO_BACKEND         - backend rnp is built with (default: botan3)
 #   CMAKE_DEPS_PREFIX_PATH - ';'-separated extra CMAKE_PREFIX_PATH entries
 #                            used to locate rnp's dependencies (e.g.
-#                            "/opt/homebrew/opt/botan@3;/opt/homebrew/opt/json-c")
+#                            "/opt/homebrew/opt/botan@3")
 #   SEXPP_PREFIX           - prefix of a sexpp installation, appended to
 #                            CMAKE_PREFIX_PATH for the static consumers
 #   RAW_DEP_LIBS           - extra libraries for the raw-flags static
@@ -86,7 +86,7 @@ default_raw_dep_libs() {
         botan)   libs="$libs -lbotan-2" ;;
         openssl) libs="$libs -lcrypto" ;;
     esac
-    printf '%s' "$libs -ljson-c -lz -lbz2"
+    printf '%s' "$libs -lz -lbz2"
 }
 
 write_consumer() {

ci/tests/pk-tests.sh

@@ -58,14 +58,6 @@ create_cmake_file() {
         find_package(BZip2 REQUIRED)
         find_package(ZLIB REQUIRED)
 
-        pkg_check_modules(JSONC IMPORTED_TARGET json-c12)
-        if(NOT JSONC_FOUND)
-            pkg_check_modules(JSONC REQUIRED IMPORTED_TARGET json-c)
-        endif(NOT JSONC_FOUND)
-
-        add_library(JSON-C::JSON-C INTERFACE IMPORTED)
-        set_target_properties(JSON-C::JSON-C PROPERTIES INTERFACE_LINK_LIBRARIES PkgConfig::JSONC)
-
         pkg_check_modules(Botan REQUIRED IMPORTED_TARGET botan-2)
         add_library(Botan::Botan  INTERFACE IMPORTED)
         set_target_properties(Botan::Botan PROPERTIES INTERFACE_LINK_LIBRARIES PkgConfig::Botan)

cmake/packaging.cmake

@@ -75,6 +75,6 @@ set(CPACK_RPM_CLI_PACKAGE_SUMMARY "${CPACK_PACKAGE_DESCRIPTION_SUMMARY} (command
 set(CPACK_FREEBSD_PACKAGE_MAINTAINER "${PACKAGING_EMAIL}")
 set(CPACK_FREEBSD_PACKAGE_ORIGIN "security/rnp")
 set(CPACK_FREEBSD_PACKAGE_CATEGORIES security)
-set(CPACK_FREEBSD_PACKAGE_DEPS bzip2 json-c botan3)
+set(CPACK_FREEBSD_PACKAGE_DEPS bzip2 botan3)
 
 include(CPack)

cmake/rnp-config.cmake.in

@@ -26,15 +26,14 @@
 
 include(CMakeFindDependencyMacro)
 
-# The exported rnp targets reference imported targets (e.g. Botan::Botan,
-# JSON-C::JSON-C) which are defined by the find modules shipped alongside
-# this file, so make those available while resolving the dependencies below.
+# The exported rnp targets reference imported targets (e.g. Botan::Botan)
+# which are defined by the find modules shipped alongside this file, so
+# make those available while resolving the dependencies below.
 set(_rnp_saved_cmake_module_path "${CMAKE_MODULE_PATH}")
 list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}/modules")
 
 # Crypto backend librnp was built against.
 @RNP_CONFIG_CRYPTO_DEPENDENCY@
-find_dependency(JSON-C 0.11)
 find_dependency(ZLIB)
 @RNP_CONFIG_BZIP2_DEPENDENCY@
 @RNP_CONFIG_SEXPP_DEPENDENCY@

codecov.yml

@@ -25,3 +25,5 @@ ignore:
   - "src/examples"
   - "src/libsexpp"
   - "src/tests"
+# Vendored single-header nlohmann/json
+  - "src/lib/nlohmann"