lttng abi documentation: clarify getter usage requirements

[lttng-modules.git] / Makefile.ABI.workarounds

# Work-around for distro-specific public modules ABI breakages.
# Some distributions break the public module instrumentation ABI
# compared to upstream stable kernels without providing other mean than
# the kernel EXTRAVERSION to figure it out. Translate this information
# into a define visible from the C preprocessor.

DEB_API_VERSION:=$(shell $(TOP_LTTNG_MODULES_DIR)/abi-debian-version.sh $(CURDIR))

ifneq ($(DEB_API_VERSION), 0)
  ccflags-y += -DDEBIAN_API_VERSION=$(DEB_API_VERSION)
endif

RHEL_API_VERSION:=$(shell $(TOP_LTTNG_MODULES_DIR)/abi-rhel-version.sh $(CURDIR))

ifneq ($(RHEL_API_VERSION), 0)
  ccflags-y += -DRHEL_API_VERSION=$(RHEL_API_VERSION)
endif

SLE_API_VERSION:=$(shell $(TOP_LTTNG_MODULES_DIR)/abi-sle-version.sh $(CURDIR))

ifneq ($(SLE_API_VERSION), 0)
  ccflags-y += -DSLE_API_VERSION=$(SLE_API_VERSION)
endif

FEDORA_REVISION_VERSION:=$(shell $(TOP_LTTNG_MODULES_DIR)/abi-fedora-version.sh $(CURDIR))

ifneq ($(FEDORA_REVISION_VERSION), 0)
  ccflags-y += -DFEDORA_REVISION_VERSION=$(FEDORA_REVISION_VERSION)
endif

RT_PATCH_VERSION:=$(shell $(TOP_LTTNG_MODULES_DIR)/rt-patch-version.sh $(CURDIR))

ifneq ($(RT_PATCH_VERSION), 0)
  ccflags-y += -DRT_PATCH_VERSION=$(RT_PATCH_VERSION)
endif

EXTRA_VERSION_NAME:=$(shell $(TOP_LTTNG_MODULES_DIR)/extra-version-name.sh $(TOP_LTTNG_MODULES_DIR))

ifneq ($(EXTRA_VERSION_NAME), 0)
  ccflags-y += -DLTTNG_EXTRA_VERSION_NAME='"$(EXTRA_VERSION_NAME)"'
endif

EXTRA_VERSION_GIT:=$(shell $(TOP_LTTNG_MODULES_DIR)/extra-version-git.sh $(TOP_LTTNG_MODULES_DIR))

ifneq ($(EXTRA_VERSION_GIT), 0)
  ccflags-y += -DLTTNG_EXTRA_VERSION_GIT='"$(EXTRA_VERSION_GIT)"'
endif

EXTRA_VERSION_PATCHES:=$(shell $(TOP_LTTNG_MODULES_DIR)/extra-version-patches.sh $(TOP_LTTNG_MODULES_DIR))

# Starting with kernel 4.12, the ftrace header was moved to private headers
# and as such is not available when building against distro headers instead
# of the full kernel sources. In the situation, define LTTNG_FTRACE_MISSING_HEADER
# so we can enable the compat code even if CONFIG_DYNAMIC_FTRACE is enabled.
ifneq ($(CONFIG_DYNAMIC_FTRACE),)
  ftrace_dep = $(srctree)/kernel/trace/trace.h
  ftrace_dep_check = $(wildcard $(ftrace_dep))
  have_ftrace_header = $(shell \
    if [ $(VERSION) -ge 5 -o \( $(VERSION) -eq 4 -a $(PATCHLEVEL) -ge 12 \) ] ; then \
      if [ -z "$(ftrace_dep_check)" ] ; then \
        echo "no" ; \
        exit ; \
      fi; \
    fi; \
    echo "yes" ; \
    )
  ifeq ($(have_ftrace_header), no)
    ccflags-y += -DLTTNG_FTRACE_MISSING_HEADER
  endif
endif