// Copyright 2014 The Bazel Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package com.google.devtools.build.lib.rules.cpp;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Joiner;
import com.google.common.base.Predicates;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.common.collect.Lists;
import com.google.devtools.build.lib.actions.ActionOwner;
import com.google.devtools.build.lib.actions.Artifact;
import com.google.devtools.build.lib.analysis.RuleContext;
import com.google.devtools.build.lib.analysis.actions.CommandLine;
import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
import com.google.devtools.build.lib.cmdline.Label;
import com.google.devtools.build.lib.collect.CollectionUtils;
import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
import com.google.devtools.build.lib.rules.cpp.CcToolchainFeatures.FeatureConfiguration;
import com.google.devtools.build.lib.rules.cpp.CcToolchainFeatures.Variables;
import com.google.devtools.build.lib.rules.cpp.Link.LinkStaticness;
import com.google.devtools.build.lib.rules.cpp.Link.LinkTargetType;
import com.google.devtools.build.lib.rules.cpp.Link.Staticness;
import com.google.devtools.build.lib.util.Pair;
import com.google.devtools.build.lib.util.Preconditions;
import com.google.devtools.build.lib.util.ShellEscaper;
import com.google.devtools.build.lib.vfs.PathFragment;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import javax.annotation.Nullable;
/**
* Represents the command line of a linker invocation. It supports executables and dynamic
* libraries as well as static libraries.
*/
@Immutable
public final class LinkCommandLine extends CommandLine {
private final String actionName;
private final String toolPath;
private final boolean codeCoverageEnabled;
private final CppConfiguration cppConfiguration;
private final ActionOwner owner;
private final CcToolchainFeatures.Variables variables;
// The feature config can be null for tests.
@Nullable private final FeatureConfiguration featureConfiguration;
@Nullable private final Artifact output;
private final ImmutableList<Artifact> buildInfoHeaderArtifacts;
private final Iterable<? extends LinkerInput> linkerInputs;
private final Iterable<? extends LinkerInput> runtimeInputs;
private final LinkTargetType linkTargetType;
private final LinkStaticness linkStaticness;
private final ImmutableList<String> linkopts;
private final ImmutableSet<String> features;
private final ImmutableMap<Artifact, Artifact> linkstamps;
private final ImmutableList<String> linkstampCompileOptions;
@Nullable private final String fdoBuildStamp;
@Nullable private final PathFragment runtimeSolibDir;
private final boolean nativeDeps;
private final boolean useTestOnlyFlags;
private final CcToolchainProvider ccProvider;
@Nullable private final Artifact paramFile;
private LinkCommandLine(
String actionName,
String toolPath,
BuildConfiguration configuration,
ActionOwner owner,
Artifact output,
ImmutableList<Artifact> buildInfoHeaderArtifacts,
Iterable<? extends LinkerInput> linkerInputs,
Iterable<? extends LinkerInput> runtimeInputs,
LinkTargetType linkTargetType,
LinkStaticness linkStaticness,
ImmutableList<String> linkopts,
ImmutableSet<String> features,
ImmutableMap<Artifact, Artifact> linkstamps,
ImmutableList<String> linkstampCompileOptions,
@Nullable String fdoBuildStamp,
@Nullable PathFragment runtimeSolibDir,
boolean nativeDeps,
boolean useTestOnlyFlags,
@Nullable Artifact paramFile,
CcToolchainFeatures.Variables variables,
@Nullable FeatureConfiguration featureConfiguration,
CcToolchainProvider ccProvider) {
this.actionName = actionName;
this.toolPath = toolPath;
this.codeCoverageEnabled = configuration.isCodeCoverageEnabled();
this.cppConfiguration = configuration.getFragment(CppConfiguration.class);
this.variables = variables;
this.featureConfiguration = featureConfiguration;
this.owner = Preconditions.checkNotNull(owner);
this.output = output;
this.buildInfoHeaderArtifacts = Preconditions.checkNotNull(buildInfoHeaderArtifacts);
this.linkerInputs = Preconditions.checkNotNull(linkerInputs);
this.runtimeInputs = Preconditions.checkNotNull(runtimeInputs);
this.linkTargetType = Preconditions.checkNotNull(linkTargetType);
this.linkStaticness = Preconditions.checkNotNull(linkStaticness);
// For now, silently ignore linkopts if this is a static library link.
this.linkopts = linkTargetType.staticness() == Staticness.STATIC
? ImmutableList.<String>of()
: Preconditions.checkNotNull(linkopts);
this.features = Preconditions.checkNotNull(features);
this.linkstamps = Preconditions.checkNotNull(linkstamps);
this.linkstampCompileOptions = linkstampCompileOptions;
this.fdoBuildStamp = fdoBuildStamp;
this.runtimeSolibDir = runtimeSolibDir;
this.nativeDeps = nativeDeps;
this.useTestOnlyFlags = useTestOnlyFlags;
this.paramFile = paramFile;
this.ccProvider = ccProvider;
}
@Nullable
public Artifact getParamFile() {
return paramFile;
}
/**
* Returns the (ordered, immutable) list of header files that contain build info.
*/
public ImmutableList<Artifact> getBuildInfoHeaderArtifacts() {
return buildInfoHeaderArtifacts;
}
/**
* Returns the (ordered, immutable) list of paths to the linker's input files.
*/
public Iterable<? extends LinkerInput> getLinkerInputs() {
return linkerInputs;
}
/**
* Returns the runtime inputs to the linker.
*/
public Iterable<? extends LinkerInput> getRuntimeInputs() {
return runtimeInputs;
}
/**
* Returns the current type of link target set.
*/
public LinkTargetType getLinkTargetType() {
return linkTargetType;
}
/**
* Returns the "staticness" of the link.
*/
public LinkStaticness getLinkStaticness() {
return linkStaticness;
}
/**
* Returns the additional linker options for this link.
*/
public ImmutableList<String> getLinkopts() {
return linkopts;
}
/**
* Returns a (possibly empty) mapping of (C++ source file, .o output file) pairs for source files
* that need to be compiled at link time.
*
* <p>This is used to embed various values from the build system into binaries to identify their
* provenance.
*/
public ImmutableMap<Artifact, Artifact> getLinkstamps() {
return linkstamps;
}
/**
* Returns the location of the C++ runtime solib symlinks. If null, the C++ dynamic runtime
* libraries either do not exist (because they do not come from the depot) or they are in the
* regular solib directory.
*/
@Nullable public PathFragment getRuntimeSolibDir() {
return runtimeSolibDir;
}
/**
* Returns true for libraries linked as native dependencies for other languages.
*/
public boolean isNativeDeps() {
return nativeDeps;
}
/**
* Returns true if this link should use test-specific flags (e.g. $EXEC_ORIGIN as the root for
* finding shared libraries or lazy binding); false by default. See bug "Please use
* $EXEC_ORIGIN instead of $ORIGIN when linking cc_tests" for further context.
*/
public boolean useTestOnlyFlags() {
return useTestOnlyFlags;
}
/** Returns the build variables used to template the crosstool for this linker invocation. */
@VisibleForTesting
public Variables getBuildVariables() {
return this.variables;
}
/**
* Splits the link command-line into a part to be written to a parameter file, and the remaining
* actual command line to be executed (which references the parameter file). Should only be used
* if getParamFile() is not null.
*/
@VisibleForTesting
final Pair<List<String>, List<String>> splitCommandline() {
List<String> args = getRawLinkArgv();
if (linkTargetType.staticness() == Staticness.STATIC) {
// Ar link commands can also generate huge command lines.
List<String> paramFileArgs = new ArrayList<>();
List<String> commandlineArgs = new ArrayList<>();
extractArgumentsForStaticLinkParamFile(args, commandlineArgs, paramFileArgs);
return Pair.of(commandlineArgs, paramFileArgs);
} else {
// Gcc link commands tend to generate humongous commandlines for some targets, which may
// not fit on some remote execution machines. To work around this we will employ the help of
// a parameter file and pass any linker options through it.
List<String> paramFileArgs = new ArrayList<>();
List<String> commandlineArgs = new ArrayList<>();
extractArgumentsForDynamicLinkParamFile(args, commandlineArgs, paramFileArgs);
return Pair.of(commandlineArgs, paramFileArgs);
}
}
/**
* Returns just the .params file portion of the command-line as a {@link CommandLine}.
*/
CommandLine paramCmdLine() {
Preconditions.checkNotNull(paramFile);
return new CommandLine() {
@Override
public Iterable<String> arguments() {
return splitCommandline().getSecond();
}
};
}
public static void extractArgumentsForStaticLinkParamFile(
List<String> args, List<String> commandlineArgs, List<String> paramFileArgs) {
commandlineArgs.add(args.get(0)); // ar command, must not be moved!
int argsSize = args.size();
for (int i = 1; i < argsSize; i++) {
String arg = args.get(i);
if (arg.startsWith("@")) {
commandlineArgs.add(arg); // params file, keep it in the command line
} else {
paramFileArgs.add(arg); // the rest goes to the params file
}
}
}
public static void extractArgumentsForDynamicLinkParamFile(
List<String> args, List<String> commandlineArgs, List<String> paramFileArgs) {
// Note, that it is not important that all linker arguments are extracted so that
// they can be moved into a parameter file, but the vast majority should.
commandlineArgs.add(args.get(0)); // gcc command, must not be moved!
int argsSize = args.size();
for (int i = 1; i < argsSize; i++) {
String arg = args.get(i);
if (arg.equals("-Wl,-no-whole-archive")) {
paramFileArgs.add("-no-whole-archive");
} else if (arg.equals("-Wl,-whole-archive")) {
paramFileArgs.add("-whole-archive");
} else if (arg.equals("-Wl,--start-group")) {
paramFileArgs.add("--start-group");
} else if (arg.equals("-Wl,--end-group")) {
paramFileArgs.add("--end-group");
} else if (arg.equals("-Wl,--start-lib")) {
paramFileArgs.add("--start-lib");
} else if (arg.equals("-Wl,--end-lib")) {
paramFileArgs.add("--end-lib");
} else if (arg.equals("--incremental-unchanged")) {
paramFileArgs.add(arg);
} else if (arg.equals("--incremental-changed")) {
paramFileArgs.add(arg);
} else if (arg.charAt(0) == '-') {
if (arg.startsWith("-l")) {
paramFileArgs.add(arg);
} else {
// Anything else starting with a '-' can stay on the commandline.
commandlineArgs.add(arg);
if (arg.equals("-o")) {
// Special case for '-o': add the following argument as well - it is the output file!
commandlineArgs.add(args.get(++i));
}
}
} else if (arg.endsWith(".a") || arg.endsWith(".lo") || arg.endsWith(".so")
|| arg.endsWith(".ifso") || arg.endsWith(".o")
|| CppFileTypes.VERSIONED_SHARED_LIBRARY.matches(arg)) {
// All objects of any kind go into the linker parameters.
paramFileArgs.add(arg);
} else {
// Everything that's left stays conservatively on the commandline.
commandlineArgs.add(arg);
}
}
}
private ImmutableList<String> getToolchainFlags() {
boolean fullyStatic = (linkStaticness == LinkStaticness.FULLY_STATIC);
boolean mostlyStatic = (linkStaticness == LinkStaticness.MOSTLY_STATIC);
boolean sharedLinkopts =
linkTargetType == LinkTargetType.DYNAMIC_LIBRARY
|| linkopts.contains("-shared")
|| cppConfiguration.hasSharedLinkOption();
List<String> toolchainFlags = new ArrayList<>();
/*
* For backwards compatibility, linkopts come _after_ inputFiles.
* This is needed to allow linkopts to contain libraries and
* positional library-related options such as
* -Wl,--begin-group -lfoo -lbar -Wl,--end-group
* or
* -Wl,--as-needed -lfoo -Wl,--no-as-needed
*
* As for the relative order of the three different flavours of linkopts
* (global defaults, per-target linkopts, and command-line linkopts),
* we have no idea what the right order should be, or if anyone cares.
*/
toolchainFlags.addAll(linkopts);
// Extra toolchain link options based on the output's link staticness.
if (fullyStatic) {
toolchainFlags.addAll(cppConfiguration.getFullyStaticLinkOptions(features, sharedLinkopts));
} else if (mostlyStatic) {
toolchainFlags.addAll(cppConfiguration.getMostlyStaticLinkOptions(features, sharedLinkopts));
} else {
toolchainFlags.addAll(cppConfiguration.getDynamicLinkOptions(features, sharedLinkopts));
}
// Extra test-specific link options.
if (useTestOnlyFlags) {
toolchainFlags.addAll(cppConfiguration.getTestOnlyLinkOptions());
}
toolchainFlags.addAll(ccProvider.getLinkOptions());
// -pie is not compatible with shared and should be
// removed when the latter is part of the link command. Should we need to further
// distinguish between shared libraries and executables, we could add additional
// command line / CROSSTOOL flags that distinguish them. But as long as this is
// the only relevant use case we're just special-casing it here.
if (linkTargetType == LinkTargetType.DYNAMIC_LIBRARY) {
Iterables.removeIf(toolchainFlags, Predicates.equalTo("-pie"));
}
return ImmutableList.copyOf(toolchainFlags);
}
/**
* Returns a raw link command for the given link invocation, including both command and arguments
* (argv). After any further usage-specific processing, this can be passed to {@link
* #finalizeWithLinkstampCommands} to give the final command line.
*
* @return raw link command line.
*/
public List<String> getRawLinkArgv() {
List<String> argv = new ArrayList<>();
// TODO(b/30109612): Extract this switch into individual crosstools once action configs are no
// longer hardcoded in CppLinkActionConfigs
switch (linkTargetType) {
case EXECUTABLE:
argv.add(cppConfiguration.getCppExecutable().getPathString());
argv.addAll(
featureConfiguration.getCommandLine(
actionName,
new Variables.Builder()
.addAll(variables)
.addStringSequenceVariable(
CppLinkActionBuilder.LEGACY_LINK_FLAGS_VARIABLE, getToolchainFlags())
.build()));
break;
case STATIC_LIBRARY:
case PIC_STATIC_LIBRARY:
case ALWAYS_LINK_STATIC_LIBRARY:
case ALWAYS_LINK_PIC_STATIC_LIBRARY:
// The static library link command follows this template:
// ar <cmd> <output_archive> <input_files...>
argv.add(cppConfiguration.getArExecutable().getPathString());
argv.addAll(cppConfiguration.getArFlags());
argv.add(output.getExecPathString());
argv.addAll(featureConfiguration.getCommandLine(actionName, variables));
break;
// Since the objc case/dynamic libs is not hardcoded in CppConfiguration, we can use the
// actual tool.
// TODO(b/30109612): make this pattern the case for all link variants.
case DYNAMIC_LIBRARY:
case OBJC_ARCHIVE:
case OBJC_FULLY_LINKED_ARCHIVE:
case OBJC_EXECUTABLE:
case OBJCPP_EXECUTABLE:
argv.add(toolPath);
argv.addAll(
featureConfiguration.getCommandLine(
actionName,
new Variables.Builder()
.addAll(variables)
.addStringSequenceVariable(
CppLinkActionBuilder.LEGACY_LINK_FLAGS_VARIABLE, getToolchainFlags())
.build()));
break;
default:
throw new IllegalArgumentException();
}
return argv;
}
List<String> getCommandLine() {
List<String> commandlineArgs;
// Try to shorten the command line by use of a parameter file.
// This makes the output with --subcommands (et al) more readable.
if (paramFile != null) {
Pair<List<String>, List<String>> split = splitCommandline();
commandlineArgs = split.first;
} else {
commandlineArgs = getRawLinkArgv();
}
return finalizeWithLinkstampCommands(commandlineArgs);
}
@Override
public List<String> arguments() {
return finalizeWithLinkstampCommands(getRawLinkArgv());
}
/**
* Takes a raw link command line and gives the final link command that will
* also first compile any linkstamps necessary. Elements of rawLinkArgv are
* shell-escaped.
*
* @param rawLinkArgv raw link command line
*
* @return final link command line suitable for execution
*/
public List<String> finalizeWithLinkstampCommands(List<String> rawLinkArgv) {
return addLinkstampingToCommand(getLinkstampCompileCommands(""), rawLinkArgv, true);
}
/**
* Takes a raw link command line and gives the final link command that will also first compile any
* linkstamps necessary. Elements of rawLinkArgv are not shell-escaped.
*
* @param rawLinkArgv raw link command line
* @param outputPrefix prefix to add before the linkstamp outputs' exec paths
*
* @return final link command line suitable for execution
*/
public List<String> finalizeAlreadyEscapedWithLinkstampCommands(
List<String> rawLinkArgv, String outputPrefix) {
return addLinkstampingToCommand(getLinkstampCompileCommands(outputPrefix), rawLinkArgv, false);
}
/**
* Adds linkstamp compilation to the (otherwise) fully specified link
* command if {@link #getLinkstamps} is non-empty.
*
* <p>Linkstamps were historically compiled implicitly as part of the link
* command, but implicit compilation doesn't guarantee consistent outputs.
* For example, the command "gcc input.o input.o foo/linkstamp.cc -o myapp"
* causes gcc to implicitly run "gcc foo/linkstamp.cc -o /tmp/ccEtJHDB.o",
* for some internally decided output path /tmp/ccEtJHDB.o, then add that path
* to the linker's command line options. The name of this path can change
* even between equivalently specified gcc invocations.
*
* <p>So now we explicitly compile these files in their own command
* invocations before running the link command, thus giving us direct
* control over the naming of their outputs. This method adds those extra
* steps as necessary.
* @param linkstampCommands individual linkstamp compilation commands
* @param linkCommand the complete list of link command arguments (after
* .params file compacting) for an invocation
* @param escapeArgs if true, linkCommand arguments are shell escaped. if
* false, arguments are returned as-is
*
* @return The original argument list if no linkstamps compilation commands
* are given, otherwise an expanded list that adds the linkstamp
* compilation commands and funnels their outputs into the link step.
* Note that these outputs only need to persist for the duration of
* the link step.
*/
private static List<String> addLinkstampingToCommand(
List<String> linkstampCommands,
List<String> linkCommand,
boolean escapeArgs) {
if (linkstampCommands.isEmpty()) {
return linkCommand;
} else {
List<String> batchCommand = Lists.newArrayListWithCapacity(3);
batchCommand.add("/bin/bash");
batchCommand.add("-c");
batchCommand.add(
Joiner.on(" && ").join(linkstampCommands) + " && "
+ (escapeArgs
? ShellEscaper.escapeJoinAll(linkCommand)
: Joiner.on(" ").join(linkCommand)));
return ImmutableList.copyOf(batchCommand);
}
}
private boolean isSharedNativeLibrary() {
return nativeDeps && cppConfiguration.shareNativeDeps();
}
/**
* Computes, for each C++ source file in {@link #getLinkstamps}, the command necessary to compile
* that file such that the output is correctly fed into the link command.
*
* <p>As these options (as well as all others) are taken into account when computing the action
* key, they do not directly contain volatile build information to avoid unnecessary relinking.
* Instead this information is passed as an additional header generated by {@link
* com.google.devtools.build.lib.rules.cpp.WriteBuildInfoHeaderAction}.
*
* @param outputPrefix prefix to add before the linkstamp outputs' exec paths
* @return a list of shell-escaped compiler commmands, one for each entry in {@link
* #getLinkstamps}
*/
public List<String> getLinkstampCompileCommands(String outputPrefix) {
if (linkstamps.isEmpty()) {
return ImmutableList.of();
}
String compilerCommand = cppConfiguration.getCppExecutable().getPathString();
List<String> commands = Lists.newArrayListWithCapacity(linkstamps.size());
for (Map.Entry<Artifact, Artifact> linkstamp : linkstamps.entrySet()) {
List<String> optionList = new ArrayList<>();
// Defines related to the build info are read from generated headers.
for (Artifact header : buildInfoHeaderArtifacts) {
optionList.add("-include");
optionList.add(header.getExecPathString());
}
String labelReplacement = Matcher.quoteReplacement(
isSharedNativeLibrary() ? output.getExecPathString() : Label.print(owner.getLabel()));
String outputPathReplacement = Matcher.quoteReplacement(
output.getExecPathString());
for (String option : linkstampCompileOptions) {
optionList.add(option
.replaceAll(Pattern.quote("${LABEL}"), labelReplacement)
.replaceAll(Pattern.quote("${OUTPUT_PATH}"), outputPathReplacement));
}
optionList.add("-DGPLATFORM=\"" + cppConfiguration + "\"");
optionList.add("-DBUILD_COVERAGE_ENABLED=" + (codeCoverageEnabled ? "1" : "0"));
// Needed to find headers included from linkstamps.
optionList.add("-I.");
// Add sysroot.
PathFragment sysroot = ccProvider.getSysroot();
if (sysroot != null) {
optionList.add("--sysroot=" + sysroot.getPathString());
}
// Add toolchain compiler options.
optionList.addAll(cppConfiguration.getCompilerOptions(features));
optionList.addAll(cppConfiguration.getCOptions());
optionList.addAll(ccProvider.getUnfilteredCompilerOptions(features));
if (CppFileTypes.CPP_SOURCE.matches(linkstamp.getKey().getExecPath())) {
optionList.addAll(cppConfiguration.getCxxOptions(features));
}
// For dynamic libraries, produce position independent code.
if (linkTargetType == LinkTargetType.DYNAMIC_LIBRARY
&& cppConfiguration.toolchainNeedsPic()) {
optionList.add("-fPIC");
}
// Stamp FDO builds with FDO subtype string
if (fdoBuildStamp != null) {
optionList.add("-D" + CppConfiguration.FDO_STAMP_MACRO + "=\"" + fdoBuildStamp + "\"");
}
// Add the compilation target.
optionList.add("-c");
optionList.add(linkstamp.getKey().getExecPathString());
// Assemble the final command, exempting outputPrefix from shell escaping.
commands.add(compilerCommand + " "
+ ShellEscaper.escapeJoinAll(optionList)
+ " -o "
+ outputPrefix
+ ShellEscaper.escapeString(linkstamp.getValue().getExecPathString()));
}
return commands;
}
/**
* A builder for a {@link LinkCommandLine}.
*/
public static final class Builder {
// TODO(bazel-team): Pass this in instead of having it here. Maybe move to cc_toolchain.
private static final ImmutableList<String> DEFAULT_LINKSTAMP_OPTIONS = ImmutableList.of(
// G3_VERSION_INFO and G3_TARGET_NAME are C string literals that normally
// contain the label of the target being linked. However, they are set
// differently when using shared native deps. In that case, a single .so file
// is shared by multiple targets, and its contents cannot depend on which
// target(s) were specified on the command line. So in that case we have
// to use the (obscure) name of the .so file instead, or more precisely
// the path of the .so file relative to the workspace root.
"-DG3_VERSION_INFO=\"${LABEL}\"",
"-DG3_TARGET_NAME=\"${LABEL}\"",
// G3_BUILD_TARGET is a C string literal containing the output of this
// link. (An undocumented and untested invariant is that G3_BUILD_TARGET is the location of
// the executable, either absolutely, or relative to the directory part of BUILD_INFO.)
"-DG3_BUILD_TARGET=\"${OUTPUT_PATH}\"");
private final BuildConfiguration configuration;
private final ActionOwner owner;
private final RuleContext ruleContext;
@Nullable private String toolPath;
@Nullable private Artifact output;
private ImmutableList<Artifact> buildInfoHeaderArtifacts = ImmutableList.of();
private Iterable<? extends LinkerInput> linkerInputs = ImmutableList.of();
private Iterable<? extends LinkerInput> runtimeInputs = ImmutableList.of();
@Nullable private LinkTargetType linkTargetType;
private LinkStaticness linkStaticness = LinkStaticness.FULLY_STATIC;
private ImmutableList<String> linkopts = ImmutableList.of();
private ImmutableSet<String> features = ImmutableSet.of();
private ImmutableMap<Artifact, Artifact> linkstamps = ImmutableMap.of();
private List<String> linkstampCompileOptions = new ArrayList<>();
@Nullable private PathFragment runtimeSolibDir;
private boolean nativeDeps;
private boolean useTestOnlyFlags;
@Nullable private Artifact paramFile;
private CcToolchainProvider toolchain;
private FdoSupport fdoSupport;
private Variables variables;
private FeatureConfiguration featureConfiguration;
// This interface is needed to support tests that don't create a
// ruleContext, in which case the configuration and action owner
// cannot be accessed off of the give ruleContext.
public Builder(BuildConfiguration configuration, ActionOwner owner, RuleContext ruleContext) {
this.configuration = configuration;
this.owner = owner;
this.ruleContext = ruleContext;
}
public Builder(RuleContext ruleContext) {
this(ruleContext.getConfiguration(), ruleContext.getActionOwner(), ruleContext);
}
public LinkCommandLine build() {
if (linkTargetType.staticness() == Staticness.STATIC) {
Preconditions.checkArgument(
linkstamps.isEmpty(),
"linkstamps may only be present on dynamic library or executable links");
Preconditions.checkArgument(
buildInfoHeaderArtifacts.isEmpty(),
"build info headers may only be present on dynamic library or executable links");
}
ImmutableList<String> actualLinkstampCompileOptions;
if (linkstampCompileOptions.isEmpty()) {
actualLinkstampCompileOptions = DEFAULT_LINKSTAMP_OPTIONS;
} else {
actualLinkstampCompileOptions = ImmutableList.copyOf(
Iterables.concat(DEFAULT_LINKSTAMP_OPTIONS, linkstampCompileOptions));
}
if (toolchain == null) {
toolchain =
Preconditions.checkNotNull(CppHelper.getToolchain(ruleContext, ":cc_toolchain"));
}
// The ruleContext can be null for some tests.
if (ruleContext != null) {
if (featureConfiguration == null) {
featureConfiguration =
CcCommon.configureFeatures(ruleContext, toolchain, CcLibraryHelper.SourceCategory.CC);
}
if (fdoSupport == null) {
fdoSupport = CppHelper.getFdoSupport(ruleContext, ":cc_toolchain").getFdoSupport();
}
}
if (variables == null) {
variables = Variables.EMPTY;
}
String actionName = linkTargetType.getActionName();
return new LinkCommandLine(
actionName,
toolPath,
configuration,
owner,
output,
buildInfoHeaderArtifacts,
linkerInputs,
runtimeInputs,
linkTargetType,
linkStaticness,
linkopts,
features,
linkstamps,
actualLinkstampCompileOptions,
CppHelper.getFdoBuildStamp(ruleContext, fdoSupport),
runtimeSolibDir,
nativeDeps,
useTestOnlyFlags,
paramFile,
variables,
featureConfiguration,
toolchain);
}
/**
* Sets the toolchain to use for link flags. If this is not called, the toolchain
* is retrieved from the rule.
*/
public Builder setToolchain(CcToolchainProvider toolchain) {
this.toolchain = toolchain;
return this;
}
public Builder setFdoSupport(FdoSupport fdoSupport) {
this.fdoSupport = fdoSupport;
return this;
}
/** Sets the tool path, with tool being the first thing on the command line */
public Builder setToolPath(String toolPath) {
this.toolPath = toolPath;
return this;
}
/** Sets the feature configuration for this link action. */
public Builder setFeatureConfiguration(FeatureConfiguration featureConfiguration) {
this.featureConfiguration = featureConfiguration;
return this;
}
/**
* Sets the type of the link. It is an error to try to set this to {@link
* LinkTargetType#INTERFACE_DYNAMIC_LIBRARY}. Note that all the static target types (see {@link
* LinkTargetType#staticness}) are equivalent, and there is no check that the output
* artifact matches the target type extension.
*/
public Builder setLinkTargetType(LinkTargetType linkTargetType) {
Preconditions.checkArgument(linkTargetType != LinkTargetType.INTERFACE_DYNAMIC_LIBRARY);
this.linkTargetType = linkTargetType;
return this;
}
/**
* Sets the primary output artifact. This must be called before calling {@link #build}.
*/
public Builder setOutput(Artifact output) {
this.output = output;
return this;
}
/**
* Sets a list of linker inputs. These get turned into linker options depending on the
* staticness and the target type. This call makes an immutable copy of the inputs, if the
* provided Iterable isn't already immutable (see {@link CollectionUtils#makeImmutable}).
*/
public Builder setLinkerInputs(Iterable<LinkerInput> linkerInputs) {
this.linkerInputs = CollectionUtils.makeImmutable(linkerInputs);
return this;
}
public Builder setRuntimeInputs(ImmutableList<LinkerInput> runtimeInputs) {
this.runtimeInputs = runtimeInputs;
return this;
}
/**
* Sets the linker options. These are passed to the linker in addition to the other linker
* options like linker inputs, symbol count options, etc. The {@link #build} method throws an
* exception if the linker options are non-empty for a static link (see {@link
* LinkTargetType#staticness()}).
*/
public Builder setLinkopts(ImmutableList<String> linkopts) {
this.linkopts = linkopts;
return this;
}
/**
* Sets how static the link is supposed to be. For static target types (see {@link
* LinkTargetType#staticness()}}), the {@link #build} method throws an exception if this
* is not {@link LinkStaticness#FULLY_STATIC}. The default setting is {@link
* LinkStaticness#FULLY_STATIC}.
*/
public Builder setLinkStaticness(LinkStaticness linkStaticness) {
this.linkStaticness = linkStaticness;
return this;
}
/**
* Sets the linkstamps. Linkstamps are additional C++ source files that are compiled as part of
* the link command. The {@link #build} method throws an exception if the linkstamps are
* non-empty for a static link (see {@link LinkTargetType#staticness()}}).
*/
public Builder setLinkstamps(ImmutableMap<Artifact, Artifact> linkstamps) {
this.linkstamps = linkstamps;
return this;
}
/**
* Adds the given C++ compiler options to the list of options passed to the linkstamp
* compilation.
*/
public Builder addLinkstampCompileOptions(List<String> linkstampCompileOptions) {
this.linkstampCompileOptions.addAll(linkstampCompileOptions);
return this;
}
/**
* The build info header artifacts are generated header files that are used for link stamping.
* The {@link #build} method throws an exception if the build info header artifacts are
* non-empty for a static link (see {@link LinkTargetType#staticness()}}).
*/
public Builder setBuildInfoHeaderArtifacts(ImmutableList<Artifact> buildInfoHeaderArtifacts) {
this.buildInfoHeaderArtifacts = buildInfoHeaderArtifacts;
return this;
}
/**
* Sets the features enabled for the rule.
*/
public Builder setFeatures(ImmutableSet<String> features) {
this.features = features;
return this;
}
/**
* Whether the resulting library is intended to be used as a native library from another
* programming language. This influences the rpath. The {@link #build} method throws an
* exception if this is true for a static link (see {@link LinkTargetType#staticness()}}).
*/
public Builder setNativeDeps(boolean nativeDeps) {
this.nativeDeps = nativeDeps;
return this;
}
/**
* Sets whether to use test-specific linker flags, e.g. {@code $EXEC_ORIGIN} instead of
* {@code $ORIGIN} in the rpath or lazy binding.
*/
public Builder setUseTestOnlyFlags(boolean useTestOnlyFlags) {
this.useTestOnlyFlags = useTestOnlyFlags;
return this;
}
public Builder setParamFile(Artifact paramFile) {
this.paramFile = paramFile;
return this;
}
public Builder setBuildVariables(Variables variables) {
this.variables = variables;
return this;
}
public Builder setRuntimeSolibDir(PathFragment runtimeSolibDir) {
this.runtimeSolibDir = runtimeSolibDir;
return this;
}
}
}