buildsystem/cargo-output.py

+#!/usr/bin/env python3
+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Copyright (C) 2022 Loïc Branstett <loic@videolabs.io>
+#
+# This program 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 program 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 program; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+
+
+# This is a wrapper/interceptor script for Cargo (the Rust package manager) that adds
+# the ability to specify an output directory for the final compiler artifact
+# (archive lib, depfile).
+#
+# Usage: ./buildsystem/cargo-output.py --output=out/ --depfile NORMAL_CARGO_INVOCATION
+# Usage: ./buildsystem/cargo-output.py --output=out/ --depfile /usr/bin/cargo
+#          --target=x86_64-unknown-linux-gnu rustc --crate-type=staticlib
+#
+# The resulting static library will be put in the output directory as well as its depfile
+# if asked (--depfile) and available
+
+import os, sys, json, pathlib, shutil, subprocess, argparse
+
+def dir_path(string):
+    if os.path.isdir(string):
+        return string
+    else:
+        raise NotADirectoryError(string)
+
+parser = argparse.ArgumentParser()
+
+parser.add_argument("--depfile", action="store_true")
+parser.add_argument("-o", "--output", type=dir_path)
+parser.add_argument("cargo_cmds", nargs=argparse.REMAINDER)
+
+args = parser.parse_args()
+
+cargo_argv = args.cargo_cmds
+
+# Insert Cargo argument `--message-format=json-render-diagnostics`
+# before a `--` (if there are any) to still be in Cargo arguments
+# and not in the inner thing (rustc, ...)
+cargo_argv.insert(
+    cargo_argv.index('--') if '--' in cargo_argv else len(cargo_argv),
+    "--message-format=json-render-diagnostics"
+)
+
+# Execute the cargo build and redirect stdout (and not stderr)
+cargo_r = subprocess.run(cargo_argv, stdout=subprocess.PIPE)
+
+# We don't use `check=True` in the above `run` method call because it
+# raise an execption and outputing a python traceback isn't useful at all
+if cargo_r.returncode != 0:
+    sys.exit(cargo_r.returncode)
+
+# Get the jsons output
+cargo_stdout = cargo_r.stdout.decode('utf-8')
+cargo_jsons = [json.loads(line) for line in cargo_stdout.splitlines()]
+
+# We are only interrested in the final artifact (ie the output, not it's deps)
+last_compiler_artifact = next(
+        j for j in reversed(cargo_jsons) if j["reason"] == "compiler-artifact")
+
+# We only take the first one, because the other one are just aliases and thus
+# are not relevant for us
+first_compiler_artifact_filename = last_compiler_artifact["filenames"][0]
+
+for filename in [first_compiler_artifact_filename]:
+    shutil.copy2(filename, args.output)
+    if args.depfile:
+        shutil.copy2(pathlib.Path(filename).with_suffix(".d"), args.output)

buildsystem/cargo-rustc-static-libs.py

+#!/usr/bin/env python3
+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Copyright (C) 2022 Loïc Branstett <loic@videolabs.io>
+#
+# This program 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 program 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 program; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+
+
+# This script is meant to find the required native libs of an empty Rust crate
+# compiled as a static lib.
+#
+# Usage: ./buildsystem/cargo-rustc-static-libs.py /usr/bin/cargo
+# Usage: ./buildsystem/cargo-rustc-static-libs.py /usr/bin/cargo --target=x86_64-unknown-linux-gnu
+#
+# The result is then printed to the standard output.
+
+import os, sys, json, subprocess, tempfile, argparse
+
+NATIVE_STATIC_LIBS="native-static-libs"
+
+parser = argparse.ArgumentParser()
+parser.add_argument("cargo_cmds", nargs=argparse.REMAINDER)
+
+args = parser.parse_args()
+
+cargo_argv = args.cargo_cmds
+cargo_argv.append("rustc")
+cargo_argv.append("--message-format=json")
+cargo_argv.append("--crate-type=staticlib")
+cargo_argv.append("--quiet")
+cargo_argv.append("--")
+cargo_argv.append("--print=native-static-libs")
+
+with tempfile.TemporaryDirectory() as tmpdir:
+    os.chdir(tmpdir)
+
+    with open("Cargo.toml", "w") as cargo_toml:
+        cargo_toml.write("""
+[package]
+name = "native-static-libs"
+version = "0.0.0"
+
+[lib]
+path = "lib.rs"
+""")
+    
+    with open("lib.rs", "w") as lib_rs:
+        lib_rs.write("#![allow(dead_code)] fn main(){}")
+
+    # Execute the cargo build and redirect stdout (and not stderr)
+    cargo_r = subprocess.run(cargo_argv, stdout=subprocess.PIPE)
+
+    # We don't use `check=True in run because it raise an execption
+    # and outputing a python traceback isn't useful at all.
+    #
+    # We also exit here so that the output o tmp dir is not cleared when
+    # there is an error.
+    if cargo_r.returncode != 0:
+        print("command: {cargo_argv}", file=sys.stderr)
+        print("cwd: {tmpdir}", file=sys.stderr)
+        sys.exit(cargo_r.returncode)
+
+# Get the jsons output
+cargo_stdout = cargo_r.stdout.decode('utf-8')
+cargo_jsons = [json.loads(line) for line in cargo_stdout.splitlines()]
+
+# Print the last message with a `NATIVE_STATIC_LIBS` message
+for j in reversed(cargo_jsons):
+    if j["reason"] == "compiler-message":
+        msg = j["message"]["message"]
+        if msg.startswith(NATIVE_STATIC_LIBS):
+            print(msg[len(NATIVE_STATIC_LIBS + ": "):])

meson.build

@@ -53,6 +53,9 @@ vlc_about = custom_target('vlc_about.h',
                                    '@INPUT2@',
                                    '@OUTPUT@'])
 
+cargo_rustc_static_libs = find_program('buildsystem/cargo-rustc-static-libs.py')
+cargo_output = find_program('buildsystem/cargo-output.py')
+
 add_project_arguments('-DHAVE_CONFIG_H=1', language: ['c', 'cpp', 'objc'])
 
 # If building with contribs, read the relevant paths from the machine file

meson_options.txt

@@ -70,6 +70,11 @@ option('extra_rust_flags',
     value : [],
     description : 'Extra RUSTFLAGS to be passed to the compiler when compiling Rust VLC modules')
 
+option('vendored_rust_deps',
+    type : 'string',
+    value : 'no',
+    description : 'Should use vendored sources: `no`, `yes` or PATH_TO_VENDORED_SOURCES')
+
 # TODO: Missing pdb option, this should probably be solved in meson itself
 
 # TODO: Missing ssp option

modules/Cargo.toml

@@ -3,6 +3,7 @@ resolver = "2"
 members = []
 
 [workspace.dependencies]
+vlcrs-core = { path = "../src/rust/vlcrs-core" }
 vlcrs-macros = { path = "../src/rust/vlcrs-macros" }
 vlcrs-messages = { path = "../src/rust/vlcrs-messages" }
 vlcrs-plugin = { path = "../src/rust/vlcrs-plugin" }

modules/Makefile.am

@@ -13,6 +13,37 @@ TESTS =
 dist_noinst_SCRIPTS = module.rc.in
 EXTRA_LTLIBRARIES =
 
+if HAVE_RUST
+
+LIBTOOL_CARGO_EXE = $(abs_srcdir)/libtool_cargo.sh
+
+CARGO_BUILD_ARGS = --target=@RUST_TARGET@ --release \
+	--crate-type=staticlib
+
+RUSTFLAGS = -C panic=abort -C opt-level=z
+if !HAVE_DYNAMIC_PLUGINS
+RUSTFLAGS += --cfg vlc_static_plugins
+endif
+
+LIBTOOL_CARGO = \
+	TARGET_CC=$(CC) TARGET_AR=$(AR) \
+	TARGET_CFLAGS="$(CFLAGS)" \
+	RUSTTARGET="@RUST_TARGET@" \
+	RUSTFLAGS="${RUSTFLAGS}" \
+	CARGO_TARGET_DIR="target-rust" \
+	LIBTOOL="$(LIBTOOL)" \
+	$(LIBTOOL_CARGO_EXE) $(CARGO) rustc $(CARGO_BUILD_ARGS)
+
+CARGO_PLUGINS_INV = ${LTLIBRARIES:%rs_plugin.la=%rs_plugin}
+CARGO_PLUGINS_CUT = ${CARGO_PLUGINS_INV:%.la=}
+CARGO_PLUGINS = ${CARGO_PLUGINS_CUT:%=%.la}
+
+CARGO_DEPS = ${CARGO_PLUGINS:%_plugin.la=${top_builddir}/modules/.libs/%.d}
+
+-include $(CARGO_DEPS)
+
+endif
+
 include common.am
 include access/Makefile.am
 include access/http/Makefile.am

modules/libtool_cargo.sh

+#!/bin/sh
+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Copyright (C) 2022 Loïc Branstett <loic@videolabs.io>
+# Copyright (C) 2024 Alexandre Janniaux <ajanni@videolabs.io>
+#
+# This program 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 program 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 program; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+
+
+# This script generate a libtool convinence library from a Cargo (Rust project)
+
+set -e # Automaticly exit on error
+
+: "${LIBTOOL:="../libtool"}"
+
+CFGS= 
+
+CARGO_RUSTC_CMD=
+while test $# -gt 2; do
+    case "$1" in
+        --cfg)
+            CFGS="${CFGS} --cfg $2"
+            shift; shift;
+            ;;
+        *)
+            CARGO_RUSTC_CMD="${CARGO_RUSTC_CMD} $1"
+            shift;
+            ;;
+    esac
+done
+
+if [ $# -lt 2 ]; then
+    echo "Invalid usage"
+    exit 1
+fi
+
+MODULE_PROJECT_DIR=$1
+LT_CONVENIENCE=$2
+
+# Build the project a first time without anything specitial)
+$CARGO_RUSTC_CMD --manifest-path="$MODULE_PROJECT_DIR/Cargo.toml" -- ${CFGS}
+
+# "Build" the project a second time and fetch the native-static-libs to link with
+NATIVE_STATIC_LIBS=$($CARGO_RUSTC_CMD --manifest-path="$MODULE_PROJECT_DIR/Cargo.toml" --quiet -- ${CFGS} --print native-static-libs 2>&1 | grep "native-static-libs" | sed "s/note: native-static-libs://" | sed "s/-lvlccore//")
+
+STATIC_LIB_NAME=$(echo $LT_CONVENIENCE | sed "s/\.la/\.a/")
+STATIC_LIB_DEP=$(echo $LT_CONVENIENCE | sed "s/\.la/\.d/")
+CARGO_STATIC_LIB_PATH="$CARGO_TARGET_DIR/$RUSTTARGET/release/$STATIC_LIB_NAME"
+CARGO_STATIC_DEP_PATH="$CARGO_TARGET_DIR/$RUSTTARGET/release/$STATIC_LIB_DEP"
+
+LT_VERSION=$(${LIBTOOL} --version | grep "libtool")
+
+cat <<EOF > $LT_CONVENIENCE
+# $LT_CONVENIENCE - a libtool library file
+# Generated by $LT_VERSION
+
+# The name that we can dlopen(3).
+dlname=''
+
+# Names of this library.
+library_names=''
+
+# The name of the static archive.
+old_library='$STATIC_LIB_NAME'
+
+# Linker flags that cannot go in dependency_libs.
+inherited_linker_flags=''
+
+# Libraries that this one depends upon.
+dependency_libs=' $NATIVE_STATIC_LIBS'
+
+# Names of additional weak libraries provided by this library
+weak_library_names=''
+
+# Version information
+current=0
+age=0
+revision=0
+
+# Is this an already installed library?
+installed=no
+
+# Should we warn about portability when linking against -modules?
+shouldnotlink=no
+
+# Files to dlopen/dlpreopen
+dlopen=''
+dlpreopen=''
+
+# Directory that this library needs to be installed in:
+libdir=''
+EOF
+
+mkdir -p "./.libs"
+ln -sf "../$LT_CONVENIENCE" "./.libs/$LT_CONVENIENCE"
+cp "$CARGO_STATIC_LIB_PATH" "./.libs/$STATIC_LIB_NAME"
+
+printf "%s" "$LT_CONVENIENCE:" > "./.libs/$STATIC_LIB_DEP"
+cat "$CARGO_STATIC_DEP_PATH" | cut -d ':' -f2 >> "./.libs/$STATIC_LIB_DEP"

modules/meson.build

@@ -199,9 +199,12 @@ rsvg_dep = dependency('librsvg-2.0', version: '>= 2.9.0', required: get_option('
 libgcrypt_dep = dependency('libgcrypt',
                             version: '>= 1.6.0',
                             required: get_option('libgcrypt'))
+# Rust support
+cargo_bin = find_program('cargo', required: get_option('rust'))
 
 # Array that holds all enabled VLC module dicts
 vlc_modules = []
+vlc_rust_modules = []
 
 # video chroma modules
 subdir('video_chroma')
@@ -376,3 +379,163 @@ foreach module : vlc_modules
         module['name']: module
     }
 endforeach
+
+# Rust/cargo common handling code
+if get_option('rust').enabled()
+    rust_optimization_args = {
+        'plain': [],
+        '0': [],
+        'g': ['-C', 'opt-level=0'],
+        '1': ['-C', 'opt-level=1'],
+        '2': ['-C', 'opt-level=2'],
+        '3': ['-C', 'opt-level=3'],
+        's': ['-C', 'opt-level=s'],
+    }
+    
+    print_static_libs_rustc = run_command([cargo_rustc_static_libs, cargo_bin],
+        check: true, capture: true)
+    rust_common_link_args = print_static_libs_rustc.stdout().split()
+
+    # Do not try to reorder those two operations, they may triger a bug in
+    # meson where array += element is not equal to array += array
+    rust_flags = get_option('extra_rust_flags')
+    rust_flags += rust_optimization_args[get_option('optimization')]
+    
+    cargo_target_dir = join_paths(meson.current_build_dir(), 'cargo_target')
+
+    extra_cargo_args = []
+    module_cargo_depends = []
+    if get_option('vendored_rust_deps') != 'no'
+        if get_option('vendored_rust_deps') == 'yes'
+            cargo_fetch_deps_tgt = custom_target('cargo_fetch_deps',
+                capture: false,
+                console: true,
+                build_by_default: true,
+                input: files('Cargo.lock'),
+                output: 'cargo_vendored_deps',
+                command: [cargo_bin, 'vendor', '--locked', '--versioned-dirs', '--manifest-path',
+                    files('Cargo.toml'), '@OUTPUT@'],
+            )
+            vendored_rust_deps_sources = cargo_fetch_deps_tgt.full_path()
+            module_cargo_depends = [cargo_fetch_deps_tgt]
+        else
+            vendored_rust_deps_sources = get_option('vendored_rust_deps')
+        endif
+
+        extra_cargo_args += ['--offline',
+            '--config', 'source.crates-io.replace-with="vendored-sources"',
+            '--config', f'source.vendored-sources.directory="@vendored_rust_deps_sources@"']
+    endif
+
+    vlcrs_core = custom_target('vlcrs_core-cargo',
+        capture: false,
+        console: true,
+        build_by_default: true,
+        input: files(
+            'vlcrs-core/Cargo.toml',
+            'vlcrs-core/src/error.rs',
+            'vlcrs-core/src/input_item.rs',
+            'vlcrs-core/src/lib.rs',
+            'vlcrs-core/src/messages.rs',
+            'vlcrs-core/src/module/args.rs',
+            'vlcrs-core/src/module/capi.rs',
+            'vlcrs-core/src/module.rs',
+            'vlcrs-core/src/object.rs',
+            'vlcrs-core/src/tick.rs',
+            'vlcrs-core/src/url.rs',
+            'vlcrs-core/sys/build.rs',
+            'vlcrs-core/sys/Cargo.toml',
+            'vlcrs-core/sys/src/lib.rs',
+            'vlcrs-core/sys/wrapper.h',
+        ),
+        output: 'libvlcrs_core.rlib',
+        depfile: 'libvlcrs_core.d',
+        depends: module_cargo_depends,
+        env: {
+          'RUSTFLAGS': rust_flags,
+          'CARGO_TARGET_DIR': cargo_target_dir
+        },
+        command: [cargo_output, '--output', '@OUTDIR@', '--depfile',
+            cargo_bin, 'build', '--locked', extra_cargo_args,
+            '--manifest-path', files('Cargo.toml'),
+            '-p', 'vlcrs-core']
+    )
+    vlcrs_core_macros = custom_target('vlcrs_core_macros-cargo',
+        capture: false,
+        console: true,
+        build_by_default: true,
+        input: files(
+            'vlcrs-core/macros/Cargo.toml',
+            'vlcrs-core/macros/src/lib.rs',
+            'vlcrs-core/macros/src/module.rs',
+        ),
+        depfile: 'libvlcrs_core_macros.d',
+        output: 'libvlcrs_core_macros.so',
+        depends: module_cargo_depends,
+        env: {
+          'RUSTFLAGS': rust_flags,
+          'CARGO_TARGET_DIR': cargo_target_dir
+        },
+        command: [cargo_output, '--output', '@OUTDIR@', '--depfile',
+            cargo_bin, 'build', '--locked', extra_cargo_args,
+            '--manifest-path', files('Cargo.toml'),
+            '-p', 'vlcrs-core-macros']
+    )
+
+    module_cargo_depends += [vlcrs_core, vlcrs_core_macros]
+
+    foreach module : vlc_rust_modules
+        if not module.has_key('name')
+            error('Got invalid vlc_rust_modules entry without \'name\' key')
+        endif
+        if not module.has_key('sources')
+            error('The vlc_rust_modules entry for ' + module['name'] + ' has no sources')
+        endif
+        if not module.has_key('cargo_toml')
+            error('The vlc_rust_modules entry for ' + module['name'] + ' has no cargo_toml')
+        endif
+
+        # This list MUST be kept in sync with the keys used below!
+        valid_dict_keys = [
+            'name',
+            'sources',
+            'cargo_toml',
+            'link_with',
+            'link_depends',
+            'dependencies',
+        ]
+        foreach key : module.keys()
+            if key not in valid_dict_keys
+                error('Invalid key \'@0@\' found in vlc_rust_modules entry for \'@1@\''
+                    .format(key, module['name']))
+            endif
+        endforeach
+
+        module_cargo = custom_target(module['name'] + '_cargo',
+            build_by_default: true,
+            input: module['cargo_toml'],
+            depends: module_cargo_depends,
+            depfile: 'lib' + module['name'] + '.d',
+            output: 'lib' + module['name'] + '.a',
+            env: {
+              'RUSTFLAGS': rust_flags,
+              'CARGO_TARGET_DIR': cargo_target_dir,
+            },
+            command: [cargo_output, '--output', '@OUTDIR@', '--depfile',
+                cargo_bin, 'rustc', '--quiet', '--color=always', '--crate-type=staticlib',
+                '--locked', extra_cargo_args, '--manifest-path', module['cargo_toml']]
+        )
+
+        library(module['name'] + '_plugin',
+            # FIXME(meson): `module_cargo` shouldn't be in `link_whole` because it prevents dead code
+            # elimination but meson doesn't yet have any way of setting the symbols to export and since
+            # `module_cargo` is an archive file everything is exported so nothing is really.
+            link_whole: module_cargo,
+            link_with: module.get('link_with', []),
+            link_args: [module.get('link_args', []), rust_common_link_args],
+            link_depends: module.get('link_depends', []),
+            dependencies: [module.get('dependencies', []), libvlccore_dep],
+            build_by_default: true,
+        )
+    endforeach
+endif