Add support for creating prebuilt Android.mk files

Add options to the `install()` and `export()` commands to export the
targets we build into Android.mk files that reference them as prebuilt
libraries with associated usage requirements (compile definitions,
include directories, link libraries).  This will allow CMake-built
projects to be imported into projects using the Android NDK build
system.

Closes: #15562

1 files changed, 149 insertions, 0 deletions

diff --git a/Source/cmInstallExportAndroidMKGenerator.cxx b/Source/cmInstallExportAndroidMKGenerator.cxx
new file mode 100644
index 0000000..43bdc01
--- /dev/null
+++ b/Source/cmInstallExportAndroidMKGenerator.cxx
@@ -0,0 +1,149 @@
+
+/*============================================================================
+  CMake - Cross Platform Makefile Generator
+  Copyright 2000-2009 Kitware, Inc., Insight Software Consortium
+
+  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 "cmInstallExportAndroidMKGenerator.h"
+
+#include <stdio.h>
+
+#include "cmExportInstallFileGenerator.h"
+#include "cmExportSet.h"
+#include "cmGeneratedFileStream.h"
+#include "cmGlobalGenerator.h"
+#include "cmInstallFilesGenerator.h"
+#include "cmInstallTargetGenerator.h"
+#include "cmLocalGenerator.h"
+#include "cmMakefile.h"
+#include "cmake.h"
+
+cmInstallExportAndroidMKGenerator::cmInstallExportAndroidMKGenerator(
+  cmExportSet* exportSet, const char* destination,
+  const char* file_permissions, std::vector<std::string> const& configurations,
+  const char* component, MessageLevel message, bool exclude_from_all,
+  const char* filename, const char* name_space, bool exportOld)
+  : cmInstallExportGenerator(exportSet, destination, file_permissions,
+                             configurations, component, message,
+                             exclude_from_all, filename, name_space, exportOld)
+{
+}
+
+cmInstallExportAndroidMKGenerator::~cmInstallExportAndroidMKGenerator()
+{
+}
+
+void cmInstallExportAndroidMKGenerator::Compute(cmLocalGenerator* lg)
+{
+  this->LocalGenerator = lg;
+  this->ExportSet->Compute(lg);
+}
+
+void cmInstallExportAndroidMKGenerator::GenerateScript(std::ostream& os)
+{
+  // Skip empty sets.
+  if (ExportSet->GetTargetExports()->empty()) {
+    std::ostringstream e;
+    e << "INSTALL(EXPORT) given unknown export \"" << ExportSet->GetName()
+      << "\"";
+    cmSystemTools::Error(e.str().c_str());
+    return;
+  }
+
+  // Create the temporary directory in which to store the files.
+  this->ComputeTempDir();
+  cmSystemTools::MakeDirectory(this->TempDir.c_str());
+
+  // Construct a temporary location for the file.
+  this->MainImportFile = this->TempDir;
+  this->MainImportFile += "/";
+  this->MainImportFile += this->FileName;
+
+  // Generate the import file for this export set.
+  this->EFGen->SetExportFile(this->MainImportFile.c_str());
+  this->EFGen->SetNamespace(this->Namespace);
+  this->EFGen->SetExportOld(this->ExportOld);
+  if (this->ConfigurationTypes->empty()) {
+    if (!this->ConfigurationName.empty()) {
+      this->EFGen->AddConfiguration(this->ConfigurationName);
+    } else {
+      this->EFGen->AddConfiguration("");
+    }
+  } else {
+    for (std::vector<std::string>::const_iterator ci =
+           this->ConfigurationTypes->begin();
+         ci != this->ConfigurationTypes->end(); ++ci) {
+      this->EFGen->AddConfiguration(*ci);
+    }
+  }
+  this->EFGen->GenerateImportFile();
+
+  // Perform the main install script generation.
+  this->cmInstallGenerator::GenerateScript(os);
+}
+
+void cmInstallExportAndroidMKGenerator::GenerateScriptConfigs(
+  std::ostream& os, Indent const& indent)
+{
+  // Create the main install rules first.
+  this->cmInstallGenerator::GenerateScriptConfigs(os, indent);
+
+  // Now create a configuration-specific install rule for the import
+  // file of each configuration.
+  std::vector<std::string> files;
+  for (std::map<std::string, std::string>::const_iterator i =
+         this->EFGen->GetConfigImportFiles().begin();
+       i != this->EFGen->GetConfigImportFiles().end(); ++i) {
+    files.push_back(i->second);
+    std::string config_test = this->CreateConfigTest(i->first);
+    os << indent << "if(" << config_test << ")\n";
+    this->AddInstallRule(os, this->Destination, cmInstallType_FILES, files,
+                         false, this->FilePermissions.c_str(), CM_NULLPTR,
+                         CM_NULLPTR, CM_NULLPTR, indent.Next());
+    os << indent << "endif()\n";
+    files.clear();
+  }
+}
+
+void cmInstallExportAndroidMKGenerator::GenerateScriptActions(
+  std::ostream& os, Indent const& indent)
+{
+  // Remove old per-configuration export files if the main changes.
+  std::string installedDir = "$ENV{DESTDIR}";
+  installedDir += this->ConvertToAbsoluteDestination(this->Destination);
+  installedDir += "/";
+  std::string installedFile = installedDir;
+  installedFile += this->FileName;
+  os << indent << "if(EXISTS \"" << installedFile << "\")\n";
+  Indent indentN = indent.Next();
+  Indent indentNN = indentN.Next();
+  Indent indentNNN = indentNN.Next();
+  /* clang-format off */
+  os << indentN << "file(DIFFERENT EXPORT_FILE_CHANGED FILES\n"
+     << indentN << "     \"" << installedFile << "\"\n"
+     << indentN << "     \"" << this->MainImportFile << "\")\n";
+  os << indentN << "if(EXPORT_FILE_CHANGED)\n";
+  os << indentNN << "file(GLOB OLD_CONFIG_FILES \"" << installedDir
+     << this->EFGen->GetConfigImportFileGlob() << "\")\n";
+  os << indentNN << "if(OLD_CONFIG_FILES)\n";
+  os << indentNNN << "message(STATUS \"Old export file \\\"" << installedFile
+     << "\\\" will be replaced.  Removing files [${OLD_CONFIG_FILES}].\")\n";
+  os << indentNNN << "file(REMOVE ${OLD_CONFIG_FILES})\n";
+  os << indentNN << "endif()\n";
+  os << indentN << "endif()\n";
+  os << indent << "endif()\n";
+  /* clang-format on */
+
+  // Install the main export file.
+  std::vector<std::string> files;
+  files.push_back(this->MainImportFile);
+  this->AddInstallRule(os, this->Destination, cmInstallType_FILES, files,
+                       false, this->FilePermissions.c_str(), CM_NULLPTR,
+                       CM_NULLPTR, CM_NULLPTR, indent);
+}