Add high level EMV library interface and refactor generated headers

* Generate emv_utils_config.h for build configuration to contain project
  version string, platform checks, and paths required by iso-codes and
  mcc-codes. This replaces isocodes_config.h and mcc_config.h.
* Add emv.h, emv.c, implement emv_lib_version_string(), and update
  emv-decode and emv-tool accordingly.

Author: leonlynch

src/CMakeLists.txt

@@ -14,8 +14,8 @@ if(NOT HAVE_TIME_H)
 	message(FATAL_ERROR "Failed to find time.h")
 endif()
 include(CheckSymbolExists)
-check_symbol_exists(clock_gettime time.h HAVE_clock_gettime)
-if(NOT HAVE_clock_gettime)
+check_symbol_exists(clock_gettime time.h HAVE_CLOCK_GETTIME)
+if(NOT HAVE_CLOCK_GETTIME)
 	message(FATAL_ERROR "Failed to find clock_gettime")
 endif()
 
@@ -63,6 +63,10 @@ else()
 	message(FATAL_ERROR "mcc-codes/mcc_codes.json not found")
 endif()
 
+# Generate emv-utils build configuration for internal use only
+# This file should NOT be installed or used by an installed header
+configure_file(emv_utils_config.h.in emv_utils_config.h)
+
 # ISO 7816 library
 add_library(iso7816
 	iso7816.c
@@ -175,6 +179,7 @@ install(
 
 # EMV library
 add_library(emv
+	emv.c
 	emv_fields.c
 	emv_tlv.c
 	emv_dol.c
@@ -184,6 +189,7 @@ add_library(emv
 	emv_tal.c
 )
 set(emv_HEADERS # PUBLIC_HEADER property requires a list instead of individual entries
+	emv.h
 	emv_tags.h
 	emv_fields.h
 	emv_tlv.h
@@ -208,9 +214,12 @@ set_target_properties(emv
 		VERSION ${CMAKE_PROJECT_VERSION}
 		SOVERSION ${CMAKE_PROJECT_VERSION_MAJOR}.${CMAKE_PROJECT_VERSION_MINOR}
 )
-target_include_directories(emv INTERFACE
-	$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
-	$<INSTALL_INTERFACE:include/emv>
+target_include_directories(emv
+	PRIVATE
+		"${CMAKE_CURRENT_BINARY_DIR}" # For generated headers
+	INTERFACE
+		$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
+		$<INSTALL_INTERFACE:include/emv>
 )
 install(
 	TARGETS
@@ -251,8 +260,6 @@ set_target_properties(emv_strings
 		VERSION ${CMAKE_PROJECT_VERSION}
 		SOVERSION ${CMAKE_PROJECT_VERSION_MAJOR}.${CMAKE_PROJECT_VERSION_MINOR}
 )
-configure_file(isocodes_config.h.in isocodes_config.h)
-configure_file(mcc_config.h.in mcc_config.h)
 target_include_directories(emv_strings
 	PRIVATE
 		"${CMAKE_CURRENT_BINARY_DIR}" # For generated headers

src/mcc_config.h.in renamed to src/emv.c

@@ -1,6 +1,6 @@
 /**
- * @file mcc_config.h
- * @brief Definitions related to the configuration of mcc-codes
+ * @file emv.c
+ * @brief High level EMV library interface
  *
  * Copyright (c) 2023 Leon Lynch
  *
@@ -19,10 +19,10 @@
  * <https://www.gnu.org/licenses/>.
  */
 
-#ifndef MCC_CONFIG_H
-#define MCC_CONFIG_H
+#include "emv.h"
+#include "emv_utils_config.h"
 
-#define MCC_JSON_BUILD_PATH "@MCC_JSON_BUILD_PATH@"
-#define MCC_JSON_INSTALL_PATH "@MCC_JSON_INSTALL_PATH@"
-
-#endif
+const char* emv_lib_version_string(void)
+{
+	return EMV_UTILS_VERSION_STRING;
+}

src/isocodes_config.h.in renamed to src/emv.h

@@ -1,8 +1,8 @@
 /**
- * @file isocodes_config.h
- * @brief Definitions related to the configuration of the iso-codes package
+ * @file emv.h
+ * @brief High level EMV library interface
  *
- * Copyright (c) 2021 Leon Lynch
+ * Copyright (c) 2023 Leon Lynch
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -19,10 +19,19 @@
  * <https://www.gnu.org/licenses/>.
  */
 
-#ifndef ISOCODES_CONFIG_H
-#define ISOCODES_CONFIG_H
+#ifndef EMV_H
+#define EMV_H
 
-#define ISOCODES_PREFIX "@IsoCodes_PREFIX@"
-#define ISOCODES_JSON_PATH "@IsoCodes_JSON_PATH@"
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+/**
+ * Retrieve EMV library version string
+ * @return Pointer to null-terminated string. Do not free.
+ */
+const char* emv_lib_version_string(void);
+
+__END_DECLS
 
 #endif

src/emv_strings.c

@@ -25,7 +25,6 @@
 #include "emv_fields.h"
 #include "isocodes_lookup.h"
 #include "mcc_lookup.h"
-#include "mcc_config.h"
 
 #include <string.h>
 #include <stdarg.h>

src/emv_utils_config.h.in

@@ -0,0 +1,36 @@
+/**
+ * @file emv_utils_config.h
+ * @brief Definitions related to emv-utils build configuration
+ *
+ * Copyright (c) 2023 Leon Lynch
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see
+ * <https://www.gnu.org/licenses/>.
+ */
+
+#ifndef EMV_UTILS_CONFIG_H
+#define EMV_UTILS_CONFIG_H
+
+#cmakedefine EMV_UTILS_VERSION_STRING "@EMV_UTILS_VERSION_STRING@"
+#cmakedefine HAVE_TIME_H
+#cmakedefine HAVE_CLOCK_GETTIME
+
+// For iso-codes
+#define ISOCODES_JSON_PATH "@IsoCodes_JSON_PATH@"
+
+// For mcc-codes
+#cmakedefine MCC_JSON_BUILD_PATH "@MCC_JSON_BUILD_PATH@"
+#cmakedefine MCC_JSON_INSTALL_PATH "@MCC_JSON_INSTALL_PATH@"
+
+#endif

src/isocodes_lookup.cpp

@@ -20,7 +20,7 @@
  */
 
 #include "isocodes_lookup.h"
-#include "isocodes_config.h"
+#include "emv_utils_config.h"
 
 #include <string>
 #include <vector>

src/mcc_lookup.cpp

@@ -20,7 +20,7 @@
  */
 
 #include "mcc_lookup.h"
-#include "mcc_config.h"
+#include "emv_utils_config.h"
 
 #include <string>
 #include <map>

tests/mcc_test.c

@@ -20,7 +20,7 @@
  */
 
 #include "mcc_lookup.h"
-#include "mcc_config.h"
+#include "emv_utils_config.h"
 
 #include <stdio.h>
 #include <string.h>

tools/CMakeLists.txt

@@ -57,10 +57,6 @@ target_link_libraries(print_helpers PRIVATE iso7816 emv emv_strings)
 # EMV decode command line tool
 if(BUILD_EMV_DECODE)
 	add_executable(emv-decode emv-decode.c)
-	set_source_files_properties(emv-decode.c
-		PROPERTIES
-			COMPILE_DEFINITIONS EMV_UTILS_VERSION_STRING="${EMV_UTILS_VERSION_STRING}"
-	)
 	target_link_libraries(emv-decode PRIVATE print_helpers iso7816 emv emv_strings iso8859)
 	if(TARGET libargp::argp)
 		target_link_libraries(emv-decode PRIVATE libargp::argp)
@@ -85,10 +81,6 @@ if(BUILD_EMV_TOOL)
 	endif()
 
 	add_executable(emv-tool emv-tool.c ../src/pcsc.c)
-	set_source_files_properties(emv-tool.c
-		PROPERTIES
-			COMPILE_DEFINITIONS EMV_UTILS_VERSION_STRING="${EMV_UTILS_VERSION_STRING}"
-	)
 	target_link_libraries(emv-tool PRIVATE print_helpers iso7816 emv emv_strings)
 	if(TARGET libargp::argp)
 		target_link_libraries(emv-tool PRIVATE libargp::argp)

tools/emv-decode.c

@@ -19,6 +19,7 @@
  * <https://www.gnu.org/licenses/>.
  */
 
+#include "emv.h"
 #include "iso7816.h"
 #include "print_helpers.h"
 #include "emv_strings.h"
@@ -286,7 +287,14 @@ static error_t argp_parser_helper(int key, char* arg, struct argp_state* state)
 		}
 
 		case EMV_DECODE_VERSION: {
-			printf("%s\n", EMV_UTILS_VERSION_STRING);
+			const char* version;
+
+			version = emv_lib_version_string();
+			if (version) {
+				printf("%s\n", version);
+			} else {
+				printf("Unknown\n");
+			}
 			exit(EXIT_SUCCESS);
 			return 0;
 		}

tools/emv-tool.c

@@ -19,6 +19,7 @@
  * <https://www.gnu.org/licenses/>.
  */
 
+#include "emv.h"
 #include "pcsc.h"
 #include "iso7816.h"
 #include "print_helpers.h"
@@ -255,7 +256,14 @@ static error_t argp_parser_helper(int key, char* arg, struct argp_state* state)
 		}
 
 		case EMV_TOOL_VERSION: {
-			printf("%s\n", EMV_UTILS_VERSION_STRING);
+			const char* version;
+
+			version = emv_lib_version_string();
+			if (version) {
+				printf("%s\n", version);
+			} else {
+				printf("Unknown\n");
+			}
 			exit(EXIT_SUCCESS);
 			return 0;
 		}