tools/zstd/patches/001-Provide-variant-pkg-config-file-for-multi-threaded-s.patch

   1 From f1f1ae369a4cefd3474b3528e8d1847b18750605 Mon Sep 17 00:00:00 2001
   2 From: Christian Marangi <ansuelsmth@gmail.com>
   3 Date: Sat, 6 Apr 2024 14:41:54 +0200
   4 Subject: [PATCH] Provide variant pkg-config file for multi-threaded static lib
   5
   6 Multi-threaded static library require -pthread to correctly link and works.
   7 The pkg-config we provide tho only works with dynamic multi-threaded library
   8 and won't provide the correct libs and cflags values if lib-mt is used.
   9
  10 To handle this, introduce an env variable MT to permit advanced user to
  11 install and generate a correct pkg-config file for lib-mt or detect if
  12 lib-mt target is called.
  13
  14 With MT env set on calling make install-pc, libzstd.pc.in is a
  15 pkg-config file for a multi-threaded static library.
  16
  17 On calling make lib-mt, a libzstd.pc is generated for a multi-threaded
  18 static library as it's what asked by the user by forcing it.
  19
  20 libzstd.pc is changed to PHONY to force regeneration of it on calling
  21 lib targets or install-pc to handle case where the same directory is
  22 used for mixed compilation.
  23
  24 This was notice while migrating from meson to make build system where
  25 meson generates a correct .pc file while make doesn't.
  26
  27 Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
  28 ---
  29  lib/Makefile      | 20 +++++++++++++++++++-
  30  lib/README.md     |  4 ++++
  31  lib/libzstd.pc.in |  4 ++--
  32  3 files changed, 25 insertions(+), 3 deletions(-)
  33
  34 --- a/lib/Makefile
  35 +++ b/lib/Makefile
  36 @@ -63,6 +63,8 @@ CPPFLAGS_DYNLIB  += -DZSTD_MULTITHREAD #
  37  LDFLAGS_DYNLIB   += -pthread
  38  CPPFLAGS_STATICLIB +=                  # static library build defaults to single-threaded
  39
  40 +# pkg-config Libs.private points to LDFLAGS_DYNLIB
  41 +PCLIB := $(LDFLAGS_DYNLIB)
  42
  43  ifeq ($(findstring GCC,$(CCVER)),GCC)
  44  decompress/zstd_decompress_block.o : CFLAGS+=-fno-tree-vectorize
  45 @@ -186,12 +188,15 @@ lib : libzstd.a libzstd
  46  %-mt : CPPFLAGS_DYNLIB  := -DZSTD_MULTITHREAD
  47  %-mt : CPPFLAGS_STATICLIB := -DZSTD_MULTITHREAD
  48  %-mt : LDFLAGS_DYNLIB   := -pthread
  49 +%-mt : PCLIB :=
  50 +%-mt : PCMTLIB := $(LDFLAGS_DYNLIB)
  51  %-mt : %
  52         @echo multi-threaded build completed
  53
  54  %-nomt : CPPFLAGS_DYNLIB  :=
  55  %-nomt : LDFLAGS_DYNLIB   :=
  56  %-nomt : CPPFLAGS_STATICLIB :=
  57 +%-nomt : PCLIB :=
  58  %-nomt : %
  59         @echo single-threaded build completed
  60
  61 @@ -292,6 +297,14 @@ PCLIBPREFIX := $(if $(findstring $(LIBDI
  62  # to PREFIX, rather than as a resolved value.
  63  PCEXEC_PREFIX := $(if $(HAS_EXPLICIT_EXEC_PREFIX),$(EXEC_PREFIX),$${prefix})
  64
  65 +
  66 +ifneq ($(MT),)
  67 +  PCLIB :=
  68 +  PCMTLIB := $(LDFLAGS_DYNLIB)
  69 +else
  70 +  PCLIB := $(LDFLAGS_DYNLIB)
  71 +endif
  72 +
  73  ifneq (,$(filter $(UNAME),FreeBSD NetBSD DragonFly))
  74    PKGCONFIGDIR ?= $(PREFIX)/libdata/pkgconfig
  75  else
  76 @@ -308,6 +321,10 @@ INSTALL_PROGRAM ?= $(INSTALL)
  77  INSTALL_DATA    ?= $(INSTALL) -m 644
  78
  79
  80 +# pkg-config library define.
  81 +# For static single-threaded library declare -pthread in Libs.private
  82 +# For static multi-threaded library declare -pthread in Libs and Cflags
  83 +.PHONY: libzstd.pc
  84  libzstd.pc: libzstd.pc.in
  85         @echo creating pkgconfig
  86         @sed \
  87 @@ -316,7 +333,8 @@ libzstd.pc: libzstd.pc.in
  88                 -e 's|@INCLUDEDIR@|$(PCINCPREFIX)$(PCINCDIR)|' \
  89                 -e 's|@LIBDIR@|$(PCLIBPREFIX)$(PCLIBDIR)|' \
  90                 -e 's|@VERSION@|$(VERSION)|' \
  91 -               -e 's|@LIBS_PRIVATE@|$(LDFLAGS_DYNLIB)|' \
  92 +               -e 's|@LIBS_MT@|$(PCMTLIB)|' \
  93 +               -e 's|@LIBS_PRIVATE@|$(PCLIB)|' \
  94                 $< >$@
  95
  96  .PHONY: install
  97 --- a/lib/README.md
  98 +++ b/lib/README.md
  99 @@ -27,12 +27,16 @@ Enabling multithreading requires 2 condi
 100
 101  For convenience, we provide a build target to generate multi and single threaded libraries:
 102  - Force enable multithreading on both dynamic and static libraries by appending `-mt` to the target, e.g. `make lib-mt`.
 103 +  Note that the `.pc` generated on calling `make lib-mt` will already include the require Libs and Cflags.
 104  - Force disable multithreading on both dynamic and static libraries by appending `-nomt` to the target, e.g. `make lib-nomt`.
 105  - By default, as mentioned before, dynamic library is multithreaded, and static library is single-threaded, e.g. `make lib`.
 106
 107  When linking a POSIX program with a multithreaded version of `libzstd`,
 108  note that it's necessary to invoke the `-pthread` flag during link stage.
 109
 110 +The `.pc` generated from `make install` or `make install-pc` always assume a single-threaded static library
 111 +is compiled. To correctly generate a `.pc` for the multi-threaded static library, set `MT=1` as ENV variable.
 112 +
 113  Multithreading capabilities are exposed
 114  via the [advanced API defined in `lib/zstd.h`](https://github.com/facebook/zstd/blob/v1.4.3/lib/zstd.h#L351).
 115
 116 --- a/lib/libzstd.pc.in
 117 +++ b/lib/libzstd.pc.in
 118 @@ -11,6 +11,6 @@ Name: zstd
 119  Description: fast lossless compression algorithm library
 120  URL: https://facebook.github.io/zstd/
 121  Version: @VERSION@
 122 -Libs: -L${libdir} -lzstd
 123 +Libs: -L${libdir} -lzstd @LIBS_MT@
 124  Libs.private: @LIBS_PRIVATE@
 125 -Cflags: -I${includedir}
 126 +Cflags: -I${includedir} @LIBS_MT@