CMake/Source/cmLocalNinjaGenerator.cxx
Brad King e15a7075b5 Add an option for explicit BYPRODUCTS of custom commands (#14963)
A common idiom in CMake-based build systems is to have custom commands
that generate files not listed explicitly as outputs so that these
files do not have to be newer than the inputs.  The file modification
times of such "byproducts" are updated only when their content changes.
Then other build rules can depend on the byproducts explicitly so that
their dependents rebuild when the content of the original byproducts
really does change.

This "undeclared byproduct" approach is necessary for Makefile, VS, and
Xcode build tools because if a byproduct were listed as an output of a
rule then the rule would always rerun when the input is newer than the
byproduct but the byproduct may never be updated.

Ninja solves this problem by offering a 'restat' feature to check
whether an output was really modified after running a rule and tracking
the fact that it is up to date separately from its timestamp.  However,
Ninja also stats all dependencies up front and will only restat files
that are listed as outputs of rules with the 'restat' option enabled.
Therefore an undeclared byproduct that does not exist at the start of
the build will be considered missing and the build will fail even if
other dependencies would cause the byproduct to be available before its
dependents build.

CMake works around this limitation by adding 'phony' build rules for
custom command dependencies in the build tree that do not have any
explicit specification of what produces them.  This is not optimal
because it prevents Ninja from reporting an error when an input to a
rule really is missing.  A better approach is to allow projects to
explicitly specify the byproducts of their custom commands so that no
phony rules are needed for them.  In order to work with the non-Ninja
generators, the byproducts must be known separately from the outputs.

Add a new "BYPRODUCTS" option to the add_custom_command and
add_custom_target commands to specify byproducts explicitly.  Teach the
Ninja generator to specify byproducts as outputs of the custom commands.
In the case of POST_BUILD, PRE_LINK, and PRE_BUILD events on targets
that link, the byproducts must be specified as outputs of the link rule
that runs the commands.  Activate 'restat' for such rules so that Ninja
knows it needs to check the byproducts, but not for link rules that have
no byproducts.
2014-11-14 16:16:00 -05:00

561 lines
17 KiB
C++

/*============================================================================
CMake - Cross Platform Makefile Generator
Copyright 2011 Peter Collingbourne <peter@pcc.me.uk>
Copyright 2011 Nicolas Despres <nicolas.despres@gmail.com>
Distributed under the OSI-approved BSD License (the "License");
see accompanying file Copyright.txt for details.
This software is distributed WITHOUT ANY WARRANTY; without even the
implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the License for more information.
============================================================================*/
#include "cmLocalNinjaGenerator.h"
#include "cmCustomCommandGenerator.h"
#include "cmMakefile.h"
#include "cmGlobalNinjaGenerator.h"
#include "cmNinjaTargetGenerator.h"
#include "cmGeneratedFileStream.h"
#include "cmSourceFile.h"
#include "cmake.h"
#include <assert.h>
cmLocalNinjaGenerator::cmLocalNinjaGenerator()
: cmLocalGenerator()
, ConfigName("")
, HomeRelativeOutputPath("")
{
#ifdef _WIN32
this->WindowsShell = true;
#endif
this->TargetImplib = "$TARGET_IMPLIB";
}
//----------------------------------------------------------------------------
// Virtual public methods.
cmLocalNinjaGenerator::~cmLocalNinjaGenerator()
{
}
void cmLocalNinjaGenerator::Generate()
{
this->SetConfigName();
this->WriteProcessedMakefile(this->GetBuildFileStream());
#ifdef NINJA_GEN_VERBOSE_FILES
this->WriteProcessedMakefile(this->GetRulesFileStream());
#endif
// We do that only once for the top CMakeLists.txt file.
if(this->isRootMakefile())
{
this->WriteBuildFileTop();
this->WritePools(this->GetRulesFileStream());
const std::string showIncludesPrefix = this->GetMakefile()
->GetSafeDefinition("CMAKE_CL_SHOWINCLUDES_PREFIX");
if (!showIncludesPrefix.empty())
{
cmGlobalNinjaGenerator::WriteComment(this->GetRulesFileStream(),
"localized /showIncludes string");
this->GetRulesFileStream()
<< "msvc_deps_prefix = " << showIncludesPrefix << "\n\n";
}
}
cmGeneratorTargetsType targets = this->GetMakefile()->GetGeneratorTargets();
for(cmGeneratorTargetsType::iterator t = targets.begin();
t != targets.end(); ++t)
{
if (t->second->Target->GetType() == cmTarget::INTERFACE_LIBRARY
|| t->second->Target->IsImported())
{
continue;
}
cmNinjaTargetGenerator* tg = cmNinjaTargetGenerator::New(t->second);
if(tg)
{
tg->Generate();
// Add the target to "all" if required.
if (!this->GetGlobalNinjaGenerator()->IsExcluded(
this->GetGlobalNinjaGenerator()->GetLocalGenerators()[0],
*t->second->Target))
this->GetGlobalNinjaGenerator()->AddDependencyToAll(t->second->Target);
delete tg;
}
}
this->WriteCustomCommandBuildStatements();
}
// Implemented in:
// cmLocalUnixMakefileGenerator3.
// Used in:
// Source/cmMakefile.cxx
// Source/cmGlobalGenerator.cxx
void cmLocalNinjaGenerator::Configure()
{
// Compute the path to use when referencing the current output
// directory from the top output directory.
this->HomeRelativeOutputPath =
this->Convert(this->Makefile->GetStartOutputDirectory(), HOME_OUTPUT);
if(this->HomeRelativeOutputPath == ".")
{
this->HomeRelativeOutputPath = "";
}
this->cmLocalGenerator::Configure();
}
// TODO: Picked up from cmLocalUnixMakefileGenerator3. Refactor it.
std::string cmLocalNinjaGenerator
::GetTargetDirectory(cmTarget const& target) const
{
std::string dir = cmake::GetCMakeFilesDirectoryPostSlash();
dir += target.GetName();
#if defined(__VMS)
dir += "_dir";
#else
dir += ".dir";
#endif
return dir;
}
//----------------------------------------------------------------------------
// Non-virtual public methods.
const cmGlobalNinjaGenerator*
cmLocalNinjaGenerator::GetGlobalNinjaGenerator() const
{
return
static_cast<const cmGlobalNinjaGenerator*>(this->GetGlobalGenerator());
}
cmGlobalNinjaGenerator* cmLocalNinjaGenerator::GetGlobalNinjaGenerator()
{
return static_cast<cmGlobalNinjaGenerator*>(this->GetGlobalGenerator());
}
//----------------------------------------------------------------------------
// Virtual protected methods.
std::string
cmLocalNinjaGenerator::ConvertToLinkReference(std::string const& lib,
OutputFormat format)
{
return this->Convert(lib, HOME_OUTPUT, format);
}
std::string
cmLocalNinjaGenerator::ConvertToIncludeReference(std::string const& path,
OutputFormat format,
bool forceFullPaths)
{
return this->Convert(path, forceFullPaths? FULL : HOME_OUTPUT, format);
}
//----------------------------------------------------------------------------
// Private methods.
cmGeneratedFileStream& cmLocalNinjaGenerator::GetBuildFileStream() const
{
return *this->GetGlobalNinjaGenerator()->GetBuildFileStream();
}
cmGeneratedFileStream& cmLocalNinjaGenerator::GetRulesFileStream() const
{
return *this->GetGlobalNinjaGenerator()->GetRulesFileStream();
}
const cmake* cmLocalNinjaGenerator::GetCMakeInstance() const
{
return this->GetGlobalGenerator()->GetCMakeInstance();
}
cmake* cmLocalNinjaGenerator::GetCMakeInstance()
{
return this->GetGlobalGenerator()->GetCMakeInstance();
}
bool cmLocalNinjaGenerator::isRootMakefile() const
{
return (strcmp(this->Makefile->GetCurrentDirectory(),
this->GetCMakeInstance()->GetHomeDirectory()) == 0);
}
void cmLocalNinjaGenerator::WriteBuildFileTop()
{
// For the build file.
this->WriteProjectHeader(this->GetBuildFileStream());
this->WriteNinjaRequiredVersion(this->GetBuildFileStream());
this->WriteNinjaFilesInclusion(this->GetBuildFileStream());
// For the rule file.
this->WriteProjectHeader(this->GetRulesFileStream());
}
void cmLocalNinjaGenerator::WriteProjectHeader(std::ostream& os)
{
cmGlobalNinjaGenerator::WriteDivider(os);
os
<< "# Project: " << this->GetMakefile()->GetProjectName() << std::endl
<< "# Configuration: " << this->ConfigName << std::endl
;
cmGlobalNinjaGenerator::WriteDivider(os);
}
void cmLocalNinjaGenerator::WriteNinjaRequiredVersion(std::ostream& os)
{
// Default required version
// Ninja generator uses 'deps' and 'msvc_deps_prefix' introduced in 1.3
std::string requiredVersion = "1.3";
// Ninja generator uses the 'console' pool if available (>= 1.5)
std::string usedVersion = this->GetGlobalNinjaGenerator()->ninjaVersion();
if(cmSystemTools::VersionCompare(cmSystemTools::OP_LESS,
usedVersion.c_str(),
"1.5") == false)
{
requiredVersion = "1.5";
}
cmGlobalNinjaGenerator::WriteComment(os,
"Minimal version of Ninja required by this file");
os
<< "ninja_required_version = "
<< requiredVersion
<< std::endl << std::endl
;
}
void cmLocalNinjaGenerator::WritePools(std::ostream& os)
{
cmGlobalNinjaGenerator::WriteDivider(os);
const char* jobpools = this->GetCMakeInstance()
->GetProperty("JOB_POOLS", cmProperty::GLOBAL);
if (jobpools)
{
cmGlobalNinjaGenerator::WriteComment(os,
"Pools defined by global property JOB_POOLS");
std::vector<std::string> pools;
cmSystemTools::ExpandListArgument(jobpools, pools);
for (size_t i = 0; i < pools.size(); ++i)
{
const std::string pool = pools[i];
const std::string::size_type eq = pool.find("=");
unsigned int jobs;
if (eq != std::string::npos &&
sscanf(pool.c_str() + eq, "=%u", &jobs) == 1)
{
os << "pool " << pool.substr(0, eq) << std::endl;
os << " depth = " << jobs << std::endl;
os << std::endl;
}
else
{
cmSystemTools::Error("Invalid pool defined by property 'JOB_POOLS': ",
pool.c_str());
}
}
}
}
void cmLocalNinjaGenerator::WriteNinjaFilesInclusion(std::ostream& os)
{
cmGlobalNinjaGenerator::WriteDivider(os);
os
<< "# Include auxiliary files.\n"
<< "\n"
;
cmGlobalNinjaGenerator::WriteInclude(os,
cmGlobalNinjaGenerator::NINJA_RULES_FILE,
"Include rules file.");
os << "\n";
}
void cmLocalNinjaGenerator::SetConfigName()
{
// Store the configuration name that will be generated.
if(const char* config =
this->GetMakefile()->GetDefinition("CMAKE_BUILD_TYPE"))
{
// Use the build type given by the user.
this->ConfigName = config;
}
else
{
// No configuration type given.
this->ConfigName = "";
}
}
//----------------------------------------------------------------------------
void cmLocalNinjaGenerator::ComputeObjectFilenames(
std::map<cmSourceFile const*, std::string>& mapping,
cmGeneratorTarget const* gt)
{
for(std::map<cmSourceFile const*, std::string>::iterator
si = mapping.begin(); si != mapping.end(); ++si)
{
cmSourceFile const* sf = si->first;
si->second = this->GetObjectFileNameWithoutTarget(*sf,
gt->ObjectDirectory);
}
}
void cmLocalNinjaGenerator::WriteProcessedMakefile(std::ostream& os)
{
cmGlobalNinjaGenerator::WriteDivider(os);
os
<< "# Write statements declared in CMakeLists.txt:" << std::endl
<< "# " << this->Makefile->GetCurrentListFile() << std::endl
;
if(this->isRootMakefile())
os << "# Which is the root file." << std::endl;
cmGlobalNinjaGenerator::WriteDivider(os);
os << std::endl;
}
std::string cmLocalNinjaGenerator::ConvertToNinjaPath(const std::string& path)
{
std::string convPath = this->Convert(path, cmLocalGenerator::HOME_OUTPUT);
#ifdef _WIN32
cmSystemTools::ReplaceString(convPath, "/", "\\");
#endif
return convPath;
}
void
cmLocalNinjaGenerator
::AppendTargetOutputs(cmTarget* target, cmNinjaDeps& outputs)
{
this->GetGlobalNinjaGenerator()->AppendTargetOutputs(target, outputs);
}
void
cmLocalNinjaGenerator
::AppendTargetDepends(cmTarget* target, cmNinjaDeps& outputs)
{
this->GetGlobalNinjaGenerator()->AppendTargetDepends(target, outputs);
}
void cmLocalNinjaGenerator::AppendCustomCommandDeps(
cmCustomCommandGenerator const& ccg,
cmNinjaDeps &ninjaDeps)
{
const std::vector<std::string> &deps = ccg.GetDepends();
for (std::vector<std::string>::const_iterator i = deps.begin();
i != deps.end(); ++i) {
std::string dep;
if (this->GetRealDependency(*i, this->GetConfigName(), dep))
ninjaDeps.push_back(ConvertToNinjaPath(dep));
}
}
std::string cmLocalNinjaGenerator::BuildCommandLine(
const std::vector<std::string> &cmdLines)
{
// If we have no commands but we need to build a command anyway, use ":".
// This happens when building a POST_BUILD value for link targets that
// don't use POST_BUILD.
if (cmdLines.empty())
#ifdef _WIN32
return "cd .";
#else
return ":";
#endif
cmOStringStream cmd;
for (std::vector<std::string>::const_iterator li = cmdLines.begin();
li != cmdLines.end(); ++li)
#ifdef _WIN32
{
if (li != cmdLines.begin())
{
cmd << " && ";
}
else if (cmdLines.size() > 1)
{
cmd << "cmd.exe /C \"";
}
cmd << *li;
}
if (cmdLines.size() > 1)
{
cmd << "\"";
}
#else
{
if (li != cmdLines.begin())
{
cmd << " && ";
}
cmd << *li;
}
#endif
return cmd.str();
}
void cmLocalNinjaGenerator::AppendCustomCommandLines(
cmCustomCommandGenerator const& ccg,
std::vector<std::string> &cmdLines)
{
if (ccg.GetNumberOfCommands() > 0) {
std::string wd = ccg.GetWorkingDirectory();
if (wd.empty())
wd = this->GetMakefile()->GetStartOutputDirectory();
cmOStringStream cdCmd;
#ifdef _WIN32
std::string cdStr = "cd /D ";
#else
std::string cdStr = "cd ";
#endif
cdCmd << cdStr << this->ConvertToOutputFormat(wd, SHELL);
cmdLines.push_back(cdCmd.str());
}
std::string launcher = this->MakeCustomLauncher(ccg);
for (unsigned i = 0; i != ccg.GetNumberOfCommands(); ++i) {
cmdLines.push_back(launcher +
this->ConvertToOutputFormat(ccg.GetCommand(i), SHELL));
std::string& cmd = cmdLines.back();
ccg.AppendArguments(i, cmd);
}
}
void
cmLocalNinjaGenerator::WriteCustomCommandBuildStatement(
cmCustomCommand const *cc, const cmNinjaDeps& orderOnlyDeps)
{
if (this->GetGlobalNinjaGenerator()->SeenCustomCommand(cc))
return;
cmCustomCommandGenerator ccg(*cc, this->GetConfigName(), this->Makefile);
const std::vector<std::string> &outputs = ccg.GetOutputs();
const std::vector<std::string> &byproducts = ccg.GetByproducts();
cmNinjaDeps ninjaOutputs(outputs.size()+byproducts.size()), ninjaDeps;
#if 0
#error TODO: Once CC in an ExternalProject target must provide the \
file of each imported target that has an add_dependencies pointing \
at us. How to know which ExternalProject step actually provides it?
#endif
std::transform(outputs.begin(), outputs.end(),
ninjaOutputs.begin(), MapToNinjaPath());
std::transform(byproducts.begin(), byproducts.end(),
ninjaOutputs.begin() + outputs.size(), MapToNinjaPath());
this->AppendCustomCommandDeps(ccg, ninjaDeps);
for (cmNinjaDeps::iterator i = ninjaOutputs.begin(); i != ninjaOutputs.end();
++i)
this->GetGlobalNinjaGenerator()->SeenCustomCommandOutput(*i);
std::vector<std::string> cmdLines;
this->AppendCustomCommandLines(ccg, cmdLines);
if (cmdLines.empty()) {
this->GetGlobalNinjaGenerator()->WritePhonyBuild(
this->GetBuildFileStream(),
"Phony custom command for " +
ninjaOutputs[0],
ninjaOutputs,
ninjaDeps,
cmNinjaDeps(),
orderOnlyDeps,
cmNinjaVars());
} else {
this->GetGlobalNinjaGenerator()->WriteCustomCommandBuild(
this->BuildCommandLine(cmdLines),
this->ConstructComment(ccg),
"Custom command for " + ninjaOutputs[0],
cc->GetUsesTerminal(),
ninjaOutputs,
ninjaDeps,
orderOnlyDeps);
}
}
void cmLocalNinjaGenerator::AddCustomCommandTarget(cmCustomCommand const* cc,
cmTarget* target)
{
this->CustomCommandTargets[cc].insert(target);
}
void cmLocalNinjaGenerator::WriteCustomCommandBuildStatements()
{
for (CustomCommandTargetMap::iterator i = this->CustomCommandTargets.begin();
i != this->CustomCommandTargets.end(); ++i) {
// A custom command may appear on multiple targets. However, some build
// systems exist where the target dependencies on some of the targets are
// overspecified, leading to a dependency cycle. If we assume all target
// dependencies are a superset of the true target dependencies for this
// custom command, we can take the set intersection of all target
// dependencies to obtain a correct dependency list.
//
// FIXME: This won't work in certain obscure scenarios involving indirect
// dependencies.
std::set<cmTarget*>::iterator j = i->second.begin();
assert(j != i->second.end());
std::vector<std::string> ccTargetDeps;
this->AppendTargetDepends(*j, ccTargetDeps);
std::sort(ccTargetDeps.begin(), ccTargetDeps.end());
++j;
for (; j != i->second.end(); ++j) {
std::vector<std::string> jDeps, depsIntersection;
this->AppendTargetDepends(*j, jDeps);
std::sort(jDeps.begin(), jDeps.end());
std::set_intersection(ccTargetDeps.begin(), ccTargetDeps.end(),
jDeps.begin(), jDeps.end(),
std::back_inserter(depsIntersection));
ccTargetDeps = depsIntersection;
}
this->WriteCustomCommandBuildStatement(i->first, ccTargetDeps);
}
}
std::string cmLocalNinjaGenerator::MakeCustomLauncher(
cmCustomCommandGenerator const& ccg)
{
const char* property = "RULE_LAUNCH_CUSTOM";
const char* property_value = this->Makefile->GetProperty(property);
if(!property_value || !*property_value)
{
return std::string();
}
// Expand rules in the empty string. It may insert the launcher and
// perform replacements.
RuleVariables vars;
vars.RuleLauncher = property;
std::string output;
const std::vector<std::string>& outputs = ccg.GetOutputs();
if(!outputs.empty())
{
RelativeRoot relative_root =
ccg.GetWorkingDirectory().empty() ? START_OUTPUT : NONE;
output = this->Convert(outputs[0], relative_root, SHELL);
}
vars.Output = output.c_str();
std::string launcher;
this->ExpandRuleVariables(launcher, vars);
if(!launcher.empty())
{
launcher += " ";
}
return launcher;
}