Implement a basic UUID v4 generator (#1799)

Signed-off-by: Juan Cruz Viotti <jv@jviotti.com>

Author: jviotti

.github/workflows/website-build.yml

@@ -16,6 +16,7 @@ jobs:
       - run: >
           cmake -S . -B ./build
           -DCMAKE_BUILD_TYPE:STRING=Release
+          -DSOURCEMETA_CORE_UUID:BOOL=OFF
           -DSOURCEMETA_CORE_GZIP:BOOL=OFF
           -DSOURCEMETA_CORE_REGEX:BOOL=OFF
           -DSOURCEMETA_CORE_URI:BOOL=OFF

.github/workflows/website-deploy.yml

@@ -26,6 +26,7 @@ jobs:
       - run: >
           cmake -S . -B ./build
           -DCMAKE_BUILD_TYPE:STRING=Release
+          -DSOURCEMETA_CORE_UUID:BOOL=OFF
           -DSOURCEMETA_CORE_GZIP:BOOL=OFF
           -DSOURCEMETA_CORE_REGEX:BOOL=OFF
           -DSOURCEMETA_CORE_URI:BOOL=OFF

CMakeLists.txt

@@ -3,6 +3,7 @@ project(core VERSION 0.0.0 LANGUAGES C CXX DESCRIPTION "Sourcemeta Core")
 list(APPEND CMAKE_MODULE_PATH "${PROJECT_SOURCE_DIR}/cmake")
 
 # Options
+option(SOURCEMETA_CORE_UUID "Build the Sourcemeta Core UUID library" ON)
 option(SOURCEMETA_CORE_GZIP "Build the Sourcemeta Core GZIP library" ON)
 option(SOURCEMETA_CORE_REGEX "Build the Sourcemeta Core Regex library" ON)
 option(SOURCEMETA_CORE_URI "Build the Sourcemeta Core URI library" ON)
@@ -47,6 +48,10 @@ if(SOURCEMETA_CORE_INSTALL)
     COMPONENT sourcemeta_${PROJECT_NAME}_dev)
 endif()
 
+if(SOURCEMETA_CORE_UUID)
+  add_subdirectory(src/core/uuid)
+endif()
+
 if(SOURCEMETA_CORE_GZIP OR SOURCEMETA_CORE_CONTRIB_ZLIB)
   find_package(ZLIB REQUIRED)
   add_subdirectory(src/core/gzip)
@@ -119,6 +124,10 @@ endif()
 if(SOURCEMETA_CORE_TESTS)
   enable_testing()
 
+  if(SOURCEMETA_CORE_UUID)
+    add_subdirectory(test/uuid)
+  endif()
+
   if(SOURCEMETA_CORE_GZIP)
     add_subdirectory(test/gzip)
   endif()

config.cmake.in

@@ -4,6 +4,7 @@
 list(APPEND SOURCEMETA_CORE_COMPONENTS ${Core_FIND_COMPONENTS})
 list(APPEND SOURCEMETA_CORE_COMPONENTS ${core_FIND_COMPONENTS})
 if(NOT SOURCEMETA_CORE_COMPONENTS)
+  list(APPEND SOURCEMETA_CORE_COMPONENTS uuid)
   list(APPEND SOURCEMETA_CORE_COMPONENTS gzip)
   list(APPEND SOURCEMETA_CORE_COMPONENTS regex)
   list(APPEND SOURCEMETA_CORE_COMPONENTS uri)
@@ -18,7 +19,9 @@ endif()
 include(CMakeFindDependencyMacro)
 
 foreach(component ${SOURCEMETA_CORE_COMPONENTS})
-  if(component STREQUAL "gzip")
+  if(component STREQUAL "uuid")
+    include("${CMAKE_CURRENT_LIST_DIR}/sourcemeta_core_uuid.cmake")
+  elseif(component STREQUAL "gzip")
     find_dependency(ZLIB CONFIG)
     include("${CMAKE_CURRENT_LIST_DIR}/sourcemeta_core_gzip.cmake")
   elseif(component STREQUAL "regex")

src/core/uuid/CMakeLists.txt

@@ -0,0 +1,5 @@
+sourcemeta_library(NAMESPACE sourcemeta PROJECT core NAME uuid SOURCES uuid.cc)
+
+if(SOURCEMETA_CORE_INSTALL)
+  sourcemeta_library_install(NAMESPACE sourcemeta PROJECT core NAME uuid)
+endif()

src/core/uuid/include/sourcemeta/core/uuid.h

@@ -0,0 +1,36 @@
+#ifndef SOURCEMETA_CORE_UUID_H_
+#define SOURCEMETA_CORE_UUID_H_
+
+#ifndef SOURCEMETA_CORE_UUID_EXPORT
+#include <sourcemeta/core/uuid_export.h>
+#endif
+
+#include <string> // std::string
+
+/// @defgroup uuid UUID
+/// @brief An growing implementation of RFC 9562 UUID.
+///
+/// This functionality is included as follows:
+///
+/// ```cpp
+/// #include <sourcemeta/core/uuid.h>
+/// ```
+
+namespace sourcemeta::core {
+
+/// @ingroup uuid
+/// Generate a random UUID v4 string. For example:
+///
+/// ```cpp
+/// #include <sourcemeta/core/uuid.h>
+/// #include <iostream>
+///
+/// std::cout << sourcemeta::core::uuidv4() << "\n";
+/// ```
+///
+/// See https://www.rfc-editor.org/rfc/rfc9562#name-uuid-version-4
+SOURCEMETA_CORE_UUID_EXPORT auto uuidv4() -> std::string;
+
+} // namespace sourcemeta::core
+
+#endif

src/core/uuid/uuid.cc

@@ -0,0 +1,32 @@
+#include <sourcemeta/core/uuid.h>
+
+#include <cstdint> // std::uint8_t
+#include <random> // std::random_device, std::mt19937, std::uniform_int_distribution
+#include <string_view> // std::string_view
+
+namespace sourcemeta::core {
+
+// Adapted from https://stackoverflow.com/a/58467162/1641422
+auto uuidv4() -> std::string {
+  static std::random_device device;
+  static std::mt19937 generator{device()};
+  static constexpr std::string_view digits = "0123456789abcdef";
+  static constexpr bool dash[] = {0, 0, 0, 0, 1, 0, 1, 0,
+                                  1, 0, 1, 0, 0, 0, 0, 0};
+  std::uniform_int_distribution<decltype(digits)::size_type> distribution(0,
+                                                                          15);
+  std::string result;
+  result.reserve(36);
+  for (std::uint8_t index = 0; index < 16; index++) {
+    if (dash[index]) {
+      result += "-";
+    }
+
+    result += digits[distribution(generator)];
+    result += digits[distribution(generator)];
+  }
+
+  return result;
+}
+
+} // namespace sourcemeta::core

test/packaging/find_package/CMakeLists.txt

@@ -5,6 +5,7 @@ set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
 find_package(Core REQUIRED)
 add_executable(core_hello hello.cc)
+target_link_libraries(core_hello PRIVATE sourcemeta::core::uuid)
 target_link_libraries(core_hello PRIVATE sourcemeta::core::gzip)
 target_link_libraries(core_hello PRIVATE sourcemeta::core::uri)
 target_link_libraries(core_hello PRIVATE sourcemeta::core::json)

test/packaging/find_package/hello.cc

@@ -5,6 +5,7 @@
 #include <sourcemeta/core/jsonpointer.h>
 #include <sourcemeta/core/jsonschema.h>
 #include <sourcemeta/core/uri.h>
+#include <sourcemeta/core/uuid.h>
 #include <sourcemeta/core/yaml.h>
 
 #include <cstdlib>  // EXIT_SUCCESS

test/uuid/CMakeLists.txt

@@ -0,0 +1,5 @@
+sourcemeta_googletest(NAMESPACE sourcemeta PROJECT core NAME uuid
+  SOURCES uuid_v4_test.cc)
+
+target_link_libraries(sourcemeta_core_uuid_unit
+  PRIVATE sourcemeta::core::uuid)