Building libyang

Table of Contents

• Requirements
  • Building Requirements
    • Optional Requirements
  • Runtime Requirements
• Building
• Build Types
  • Release
  • Debug
  • ABICheck
  • DocOnly

libyang utilizes CMake build system to detect necessary dependencies, checkout the build environment and prepare Makefiles for the compilation of the library and acompanied tools.

Requirements

Building Requirements

• C compiler (gcc, clang, ...)
• CMake >= 2.8.12
• libpcre2 (including headers - devel package) >= 10.30

Optional Requirements

• doxygen (for generating documentation)
• cmocka >= 1.0.0 (for tests)
• valgrind (for enhanced testing)
• gcov (for code coverage)
• lcov (for code coverage)
• genhtml (for code coverage)

Runtime Requirements

• libpcre2 (runtime package) >= 10.30

Building

To simply build libyang library and the accompanied tools with the default settings, follow these steps (the # character indicates command(s) to run with root privileges):

$ mkdir build; cd build
$ cmake ..
$ make
# make install

The default settings can be changed with various CMake variables set via command line or using e.g. ccmake(1) tool. The following sections introduces those variables and explain their meaning.

Build Types

There are several build types according to the primary goal of using the built binaries.

Release

Build type to produce final binaries for production use without any debug option. The compiler flags are set as follows:

-Wall -Wextra -Wno-missing-field-initializers -std=c99 -O3 -DNDEBUG

Here is the list of the selected additional options available in the Release build type.

Option	Description	Default
ENABLE_BUILD_TESTS	Build tests.	OFF
ENABLE_VALGRIND_TESTS	Build tests with valgrind.	OFF
ENABLE_COVERAGE	Build code coverage report from tests.	OFF
ENABLE_FUZZ_TARGETS	Build target programs suitable for fuzzing with AFL.	OFF
BUILD_SHARED_LIBS	Build shared (.so) instead of static (.a) library	ON
INTERNAL_DOCS	Include developers notes and internal API description into generated Documentation	OFF

Here is the list of available important targets for the make(1) tool:

Target	Description
all	Default target, builds libyang library (.so), yanglint(1) and yangre(1).
clean	Removes files generated by the make process.
cclean	Extends the clean target by removing all the cmake generated files.
doc	Generate HTML documentation. Requires doxygen(1).

Debug

Debug is the default build type, the produced binaries include additional debug information and the prepared tests are also built. The compiler flags are set as follows:

-Wall -Wextra -Wno-missing-field-initializers -std=c99 -g3 -O0

Here is the list of the selected additional options available in the Debug build type.

Option	Description	Default
ENABLE_BUILD_TESTS	Build tests.	ON
ENABLE_VALGRIND_TESTS	Build tests with valgrind.	ON
ENABLE_COVERAGE	Build code coverage report from tests.	OFF
ENABLE_FUZZ_TARGETS	Build target programs suitable for fuzzing with AFL.	OFF
BUILD_SHARED_LIBS	Build shared (.so) instead of static (.a) library	ON
INTERNAL_DOCS	Include developers notes and internal API description into generated Documentation	OFF

Here is the list of available important targets for the make(1) tool:

Target	Description
all	Default target, builds libyang library (.so), yanglint(1) and yangre(1).
clean	Removes files generated by the make process.
cclean	Extends the clean target by removing all the cmake generated files.
doc	Generate HTML documentation. Requires doxygen(1).
test	Run implementation tests. Requires cmocka (and valgrind(1) for part of the tests).
format	Reformat source codes using uncrustify(1).
format-check	Dry-run of the format target.

ABICheck

Special build type to perform check of the ABI/API compatibility and generate reports. In addition to the basic requirements, the build type requires some of the ABI Laboratory tools: abi-dumper(1) and abi-compliance-checker(1).

The compiler flags are set as follows:

-Wall -Wextra -Wno-missing-field-initializers -std=c99 -g -Og

All the additional options are switched OFF and the settings should not be changed.

Here is the list of available important targets for the make(1) tool:

Target	Description
all	Default target, builds libyang library (.so), yanglint(1) and yangre(1).
clean	Removes files generated by the make process.
cclean	Extends the clean target by removing all the cmake generated files.
doc	Generate HTML documentation. Requires doxygen(1).
abi-check	Check the backward compatibility of the API/ABI changes. Requires abi-compliance-checker(1) and abi-dump(1).
abi-dump	Helper target for abi-check generating API/ABI reports. Requires abi-dump(1).

DocOnly

Special build type to avoid any requirements except those for building documentation. There are no compiler flags set since the build type does not allow building any binary output. The settings of the additional options should not be changed.

Here is the list of available important targets for the make(1) tool:

Target	Description
all	Default target, does nothing.
doc	Generate HTML documentation. Requires doxygen(1).