[dpdk-dev] [PATCH v3] build: fix soname info for 19.11 compatiblity

[Bruce Richardson <bruce.richardson@intel.com>]

The soname for each stable ABI version should be just the ABI version major
number without the minor number. Unfortunately both major and minor were
used causing version 20.1 to be incompatible with 20.0.

This patch fixes the issue by switching from 2-part to 3-part ABI version
numbers so that we can keep 20.0 as soname and using the final digits to
identify the 20.x releases which are ABI compatible. This requires changes
to both make and meson builds to handle the three-digit version and shrink
it to 2-digit for soname.

The final fix needed in this patch is to adjust the library version number
for the ethtool example library, which needs to be upped to 2-digits, as
external libraries using the DPDK build system also use the logic in this
file.

Fixes: cba806e07d6f ("build: change ABI versioning to global")

Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---

V3:
* fixed issues with building ethtool example app.
V2:
* adjusted the meson version to work correctly with both 2-part and
  3-part ABI versions, so it will work correctly even with no changes
  for a 21.x ABI version number
* adjusted the versions of the experimental libs so that they are
  consistent between meson and make, and also consistent with v19.11

---
 ABI_VERSION                   |  2 +-
 config/meson.build            | 16 +++++++++++++---
 drivers/meson.build           |  4 ++--
 examples/ethtool/lib/Makefile |  2 +-
 lib/meson.build               |  4 ++--
 mk/rte.lib.mk                 | 13 ++++++++-----
 6 files changed, 27 insertions(+), 14 deletions(-)

diff --git a/ABI_VERSION b/ABI_VERSION
index 2e73f8d2a..fcc01369a 100644
--- a/ABI_VERSION
+++ b/ABI_VERSION
@@ -1 +1 @@
-20.1
+20.0.1
diff --git a/config/meson.build b/config/meson.build
index 364a8d739..01911ecf9 100644
--- a/config/meson.build
+++ b/config/meson.build
@@ -20,9 +20,19 @@ pver = meson.project_version().split('.')
 major_version = '@0@.@1@'.format(pver.get(0), pver.get(1))
 abi_version = run_command(find_program('cat', 'more'),
 	abi_version_file).stdout().strip()
-# experimental libraries are versioned as 0.majorminor versions, e.g. 0.201
-ever = abi_version.split('.')
-experimental_abi_version = '0.@0@@1@'.format(ever.get(0), ever.get(1))
+
+# Regular libraries have the abi_version as the filename extension
+# and have the soname be all but the final part of the abi_version.
+# Experimental libraries have soname with '0.major'
+# and the filename suffix as 0.majorminor versions,
+# e.g. v20.1 => librte_stable.so.20.1, librte_experimental.so.0.201
+#    sonames => librte_stable.so.20, librte_experimental.so.0.20
+# e.g. v20.0.1 => librte_stable.so.20.0.1, librte_experimental.so.0.2001
+#      sonames => librte_stable.so.20.0, librte_experimental.so.0.200
+abi_va = abi_version.split('.')
+stable_so_version = abi_va.length() == 2 ? abi_va[0] : abi_va[0] + '.' + abi_va[1]
+experimental_abi_version = '0.' + ''.join(abi_va)
+experimental_so_version = '0.' + ''.join(stable_so_version.split('.'))
 
 # extract all version information into the build configuration
 dpdk_conf.set('RTE_VER_YEAR', pver.get(0).to_int())
diff --git a/drivers/meson.build b/drivers/meson.build
index 72eec4608..4b17662b7 100644
--- a/drivers/meson.build
+++ b/drivers/meson.build
@@ -132,10 +132,10 @@ foreach class:dpdk_driver_classes
 
 			if is_experimental != 0
 				lib_version = experimental_abi_version
-				so_version = experimental_abi_version
+				so_version = experimental_so_version
 			else
 				lib_version = abi_version
-				so_version = abi_version
+				so_version = stable_so_version
 			endif
 
 			# now build the static driver
diff --git a/examples/ethtool/lib/Makefile b/examples/ethtool/lib/Makefile
index 9da7dc3ba..649474127 100644
--- a/examples/ethtool/lib/Makefile
+++ b/examples/ethtool/lib/Makefile
@@ -18,7 +18,7 @@ endif
 # library name
 LIB = librte_ethtool.a
 
-LIBABIVER := 1
+LIBABIVER := 0.1
 
 # all source are stored in SRC-Y
 SRCS-y := rte_ethtool.c
diff --git a/lib/meson.build b/lib/meson.build
index 6ceb5e756..0af3efab2 100644
--- a/lib/meson.build
+++ b/lib/meson.build
@@ -113,10 +113,10 @@ foreach l:libraries
 
 			if is_experimental != 0
 				lib_version = experimental_abi_version
-				so_version = experimental_abi_version
+				so_version = experimental_so_version
 			else
 				lib_version = abi_version
-				so_version = abi_version
+				so_version = stable_so_version
 			endif
 
 			# first build static lib
diff --git a/mk/rte.lib.mk b/mk/rte.lib.mk
index 655a1b143..b1a8372cc 100644
--- a/mk/rte.lib.mk
+++ b/mk/rte.lib.mk
@@ -11,14 +11,16 @@ EXTLIB_BUILD ?= n
 # VPATH contains at least SRCDIR
 VPATH += $(SRCDIR)
 
-ifneq ($(shell grep -s "^DPDK_" $(SRCDIR)/$(EXPORT_MAP)),)
-LIBABIVER := $(shell cat $(RTE_SRCDIR)/ABI_VERSION)
-else ifeq ($(LIBABIVER),)
+LIBABIVER ?= $(shell cat $(RTE_SRCDIR)/ABI_VERSION)
+SOVER := $(basename $(LIBABIVER))
+ifeq ($(shell grep -s "^DPDK_" $(SRCDIR)/$(EXPORT_MAP)),)
 # EXPERIMENTAL ABI is versioned as 0.major+minor, e.g. 0.201 for 20.1 ABI
-LIBABIVER := 0.$(shell cat $(RTE_SRCDIR)/ABI_VERSION | tr -d '.')
+LIBABIVER := 0.$(shell echo $(LIBABIVER) | tr -d '.')
+SOVER := 0.$(shell echo $(SOVER) | tr -d '.')
 endif
 
 ifeq ($(CONFIG_RTE_BUILD_SHARED_LIB),y)
+SONAME := $(patsubst %.a,%.so.$(SOVER),$(LIB))
 LIB := $(patsubst %.a,%.so.$(LIBABIVER),$(LIB))
 ifeq ($(EXTLIB_BUILD),n)
 CPU_LDFLAGS += --version-script=$(SRCDIR)/$(EXPORT_MAP)
@@ -74,7 +76,7 @@ NO_UNDEFINED := -z defs
 endif
 
 O_TO_S = $(LD) -L$(RTE_SDK_BIN)/lib $(_CPU_LDFLAGS) $(EXTRA_LDFLAGS) \
-	  -shared $(OBJS-y) $(NO_UNDEFINED) $(LDLIBS) -Wl,-soname,$(LIB) -o $(LIB)
+	  -shared $(OBJS-y) $(NO_UNDEFINED) $(LDLIBS) -Wl,-soname,$(SONAME) -o $(LIB)
 O_TO_S_STR = $(subst ','\'',$(O_TO_S)) #'# fix syntax highlight
 O_TO_S_DISP = $(if $(V),"$(O_TO_S_STR)","  LD $(@)")
 O_TO_S_DO = @set -e; \
@@ -133,6 +135,7 @@ $(RTE_OUTPUT)/lib/$(LIB): $(LIB)
 	$(Q)cp -f $(LIB) $(RTE_OUTPUT)/lib
 ifeq ($(CONFIG_RTE_BUILD_SHARED_LIB),y)
 	$(Q)ln -s -f $< $(shell echo $@ | sed 's/\.so.*/.so/')
+	$(Q)ln -s -f $< $(shell echo $@ | sed 's/\.so.*/.so.$(SOVER)/')
 endif
 
 #
-- 
2.23.0