Common.cpp - platform/system/tools/sysprop - Git at Google

 /*
  * Copyright (C) 2018 The Android Open Source Project
  *
  * 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.
  */

 #include "Common.h"

 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>

 #include <algorithm>
 #include <cctype>
 #include <cerrno>
 #include <cmath>
 #include <cstdlib>
 #include <cstring>
 #include <initializer_list>
 #include <memory>
 #include <regex>
 #include <string>
 #include <unordered_set>
 #include <vector>

 #include <android-base/file.h>
 #include <android-base/strings.h>
 #include <google/protobuf/text_format.h>

 #include "sysprop.pb.h"

 namespace {

 std::string GenerateDefaultPropName(const sysprop::Properties& props,
                                     const sysprop::Property& prop);
 bool IsCorrectIdentifier(const std::string& name);
 bool ValidateProp(const sysprop::Properties& props,
                   const sysprop::Property& prop, std::string* err);
 bool ValidateProps(const sysprop::Properties& props, std::string* err);

 std::string GenerateDefaultPropName(const sysprop::Properties& props,
                                     const sysprop::Property& prop) {
   std::string ret;

   if (prop.access() != sysprop::ReadWrite) ret = "ro.";

   switch (props.owner()) {
     case sysprop::Vendor:
       ret += "vendor.";
       break;
     case sysprop::Odm:
       ret += "odm.";
       break;
     default:
       break;
   }

   ret += prop.api_name();

   return ret;
 }

 bool IsCorrectIdentifier(const std::string& name) {
   if (name.empty()) return false;
   if (std::isalpha(name[0]) == 0 && name[0] != '_') return false;

   return std::all_of(name.begin() + 1, name.end(), [](char ch) {
     return std::isalnum(ch) != 0 || ch == '_';
   });
 }

 bool IsCorrectPropertyOrApiName(const std::string& name) {
   if (name.empty()) return false;

   static std::unordered_set<char> allowed{'_', '-', '.'};

   return std::all_of(name.begin(), name.end(), [](char ch) {
     return std::isalnum(ch) != 0 || allowed.count(ch) != 0;
   });
 }

 bool ValidateProp(const sysprop::Properties& props,
                   const sysprop::Property& prop, std::string* err) {
   if (!IsCorrectPropertyOrApiName(prop.api_name())) {
     if (err) *err = "Invalid API name \"" + prop.api_name() + "\"";
     return false;
   }

   if (prop.type() == sysprop::Enum || prop.type() == sysprop::EnumList) {
     std::vector<std::string> names =
         android::base::Split(prop.enum_values(), "|");
     if (names.empty()) {
       if (err)
         *err = "Enum values are empty for API \"" + prop.api_name() + "\"";
       return false;
     }

     for (const std::string& name : names) {
       if (!IsCorrectIdentifier(name)) {
         if (err)
           *err = "Invalid enum value \"" + name + "\" for API \"" +
                  prop.api_name() + "\"";
         return false;
       }
     }

     std::unordered_set<std::string> name_set;
     for (const std::string& name : names) {
       if (!name_set.insert(ToUpper(name)).second) {
         if (err)
           *err = "Duplicated enum value \"" + name + "\" for API \"" +
                  prop.api_name() + "\"";
         return false;
       }
     }
   }

   std::string prop_name = prop.prop_name();
   if (prop_name.empty()) prop_name = GenerateDefaultPropName(props, prop);

   if (!IsCorrectPropertyOrApiName(prop_name)) {
     if (err) *err = "Invalid prop name \"" + prop.prop_name() + "\"";
     return false;
   }

   static const std::regex vendor_regex("([^.]+\\.)?vendor\\..+");
   static const std::regex odm_regex("([^.]+\\.)?odm\\..+");

   switch (props.owner()) {
     case sysprop::Platform:
       if (std::regex_match(prop_name, vendor_regex) ||
           std::regex_match(prop_name, odm_regex)) {
         if (err)
           *err = "Prop \"" + prop_name +
                  "\" owned by platform cannot have vendor. or odm. namespace";
         return false;
       }
       break;
     case sysprop::Vendor:
       if (!std::regex_match(prop_name, vendor_regex)) {
         if (err)
           *err = "Prop \"" + prop_name +
                  "\" owned by vendor should have vendor. namespace";
         return false;
       }
       break;
     case sysprop::Odm:
       if (!std::regex_match(prop_name, odm_regex)) {
         if (err)
           *err = "Prop \"" + prop_name +
                  "\" owned by odm should have odm. namespace";
         return false;
       }
       break;
     default:
       break;
   }

   switch (prop.access()) {
     case sysprop::ReadWrite:
       if (android::base::StartsWith(prop_name, "ro.")) {
         if (err) {
           *err = "Prop \"" + prop_name +
                  "\" is ReadWrite and also have prefix \"ro.\"";
         }
         return false;
       }
       break;
     default:
       /*
        * TODO: Some properties don't have prefix "ro." but not written in any
        * Java or C++ codes. They might be misnamed and should be readonly. Will
        * uncomment this check after fixing them all / or making a whitelist for
        * them
       if (!android::base::StartsWith(prop_name, "ro.")) {
         if (err) {
           *err = "Prop \"" + prop_name +
                  "\" isn't ReadWrite, but don't have prefix \"ro.\"";
         }
         return false;
       }
       */
       break;
   }

   return true;
 }

 bool ValidateProps(const sysprop::Properties& props, std::string* err) {
   std::vector<std::string> names = android::base::Split(props.module(), ".");
   if (names.size() <= 1) {
     if (err) *err = "Invalid module name \"" + props.module() + "\"";
     return false;
   }

   for (const auto& name : names) {
     if (!IsCorrectIdentifier(name)) {
       if (err) *err = "Invalid name \"" + name + "\" in module";
       return false;
     }
   }

   if (props.prop_size() == 0) {
     if (err) *err = "There is no defined property";
     return false;
   }

   for (int i = 0; i < props.prop_size(); ++i) {
     const auto& prop = props.prop(i);
     if (!ValidateProp(props, prop, err)) return false;
   }

   std::unordered_set<std::string> prop_names;

   for (int i = 0; i < props.prop_size(); ++i) {
     const auto& prop = props.prop(i);
     auto res = prop_names.insert(ApiNameToIdentifier(prop.api_name()));

     if (!res.second) {
       if (err) *err = "Duplicated API name \"" + prop.api_name() + "\"";
       return false;
     }
   }

   return true;
 }

 }  // namespace

 // For directory functions, we could use <filesystem> of C++17 if supported..
 bool CreateDirectories(const std::string& path) {
   struct stat st;

   // If already exists..
   if (stat(path.c_str(), &st) == 0) {
     return false;
   }

   size_t last_slash = path.rfind('/');
   if (last_slash > 0 && last_slash != std::string::npos) {
     std::string parent = path.substr(0, last_slash);
     if (!IsDirectory(parent) && !CreateDirectories(parent)) return false;
   }

   // It's very unlikely, but if path contains ".." or any symbolic links, it
   // might already be created before this line.
   return mkdir(path.c_str(), 0755) == 0 || IsDirectory(path);
 }

 bool IsDirectory(const std::string& path) {
   struct stat st;

   if (stat(path.c_str(), &st) == -1) return false;
   return S_ISDIR(st.st_mode);
 }

 bool IsListProp(const sysprop::Property& prop) {
   switch (prop.type()) {
     case sysprop::BooleanList:
     case sysprop::IntegerList:
     case sysprop::LongList:
     case sysprop::DoubleList:
     case sysprop::StringList:
     case sysprop::EnumList:
       return true;
     default:
       return false;
   }
 }

 std::string GetModuleName(const sysprop::Properties& props) {
   const std::string& module = props.module();
   return module.substr(module.rfind('.') + 1);
 }

 bool ParseProps(const std::string& input_file_path, sysprop::Properties* props,
                 std::string* err) {
   std::string file_contents;

   if (!android::base::ReadFileToString(input_file_path, &file_contents, true)) {
     *err = "Error reading file " + input_file_path + ": " + strerror(errno);
     return false;
   }

   if (!google::protobuf::TextFormat::ParseFromString(file_contents, props)) {
     *err = "Error parsing file " + input_file_path;
     return false;
   }

   if (!ValidateProps(*props, err)) {
     return false;
   }

   for (int i = 0; i < props->prop_size(); ++i) {
     // set each optional field to its default value
     sysprop::Property& prop = *props->mutable_prop(i);
     if (prop.prop_name().empty())
       prop.set_prop_name(GenerateDefaultPropName(*props, prop));
   }

   return true;
 }

 std::string ToUpper(std::string str) {
   for (char& ch : str) {
     ch = toupper(ch);
   }
   return str;
 }

 std::string ApiNameToIdentifier(const std::string& name) {
   static const std::regex kRegexAllowed{"-|\\."};
   return (isdigit(name[0]) ? "_" : "") +
          std::regex_replace(name, kRegexAllowed, "_");
 }
	/*
	* Copyright (C) 2018 The Android Open Source Project
	*
	* 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.
	*/

	#include "Common.h"

	#include <sys/stat.h>
	#include <sys/types.h>
	#include <unistd.h>

	#include <algorithm>
	#include <cctype>
	#include <cerrno>
	#include <cmath>
	#include <cstdlib>
	#include <cstring>
	#include <initializer_list>
	#include <memory>
	#include <regex>
	#include <string>
	#include <unordered_set>
	#include <vector>

	#include <android-base/file.h>
	#include <android-base/strings.h>
	#include <google/protobuf/text_format.h>

	#include "sysprop.pb.h"

	namespace {

	std::string GenerateDefaultPropName(const sysprop::Properties& props,
	const sysprop::Property& prop);
	bool IsCorrectIdentifier(const std::string& name);
	bool ValidateProp(const sysprop::Properties& props,
	const sysprop::Property& prop, std::string* err);
	bool ValidateProps(const sysprop::Properties& props, std::string* err);

	std::string GenerateDefaultPropName(const sysprop::Properties& props,
	const sysprop::Property& prop) {
	std::string ret;

	if (prop.access() != sysprop::ReadWrite) ret = "ro.";

	switch (props.owner()) {
	case sysprop::Vendor:
	ret += "vendor.";
	break;
	case sysprop::Odm:
	ret += "odm.";
	break;
	default:
	break;
	}

	ret += prop.api_name();

	return ret;
	}

	bool IsCorrectIdentifier(const std::string& name) {
	if (name.empty()) return false;
	if (std::isalpha(name[0]) == 0 && name[0] != '_') return false;

	return std::all_of(name.begin() + 1, name.end(), [](char ch) {
	return std::isalnum(ch) != 0 \|\| ch == '_';
	});
	}

	bool IsCorrectPropertyOrApiName(const std::string& name) {
	if (name.empty()) return false;

	static std::unordered_set<char> allowed{'_', '-', '.'};

	return std::all_of(name.begin(), name.end(), [](char ch) {
	return std::isalnum(ch) != 0 \|\| allowed.count(ch) != 0;
	});
	}

	bool ValidateProp(const sysprop::Properties& props,
	const sysprop::Property& prop, std::string* err) {
	if (!IsCorrectPropertyOrApiName(prop.api_name())) {
	if (err) *err = "Invalid API name \"" + prop.api_name() + "\"";
	return false;
	}

	if (prop.type() == sysprop::Enum \|\| prop.type() == sysprop::EnumList) {
	std::vector<std::string> names =
	android::base::Split(prop.enum_values(), "\|");
	if (names.empty()) {
	if (err)
	*err = "Enum values are empty for API \"" + prop.api_name() + "\"";
	return false;
	}

	for (const std::string& name : names) {
	if (!IsCorrectIdentifier(name)) {
	if (err)
	*err = "Invalid enum value \"" + name + "\" for API \"" +
	prop.api_name() + "\"";
	return false;
	}
	}

	std::unordered_set<std::string> name_set;
	for (const std::string& name : names) {
	if (!name_set.insert(ToUpper(name)).second) {
	if (err)
	*err = "Duplicated enum value \"" + name + "\" for API \"" +
	prop.api_name() + "\"";
	return false;
	}
	}
	}

	std::string prop_name = prop.prop_name();
	if (prop_name.empty()) prop_name = GenerateDefaultPropName(props, prop);

	if (!IsCorrectPropertyOrApiName(prop_name)) {
	if (err) *err = "Invalid prop name \"" + prop.prop_name() + "\"";
	return false;
	}

	static const std::regex vendor_regex("([^.]+\\.)?vendor\\..+");
	static const std::regex odm_regex("([^.]+\\.)?odm\\..+");

	switch (props.owner()) {
	case sysprop::Platform:
	if (std::regex_match(prop_name, vendor_regex) \|\|
	std::regex_match(prop_name, odm_regex)) {
	if (err)
	*err = "Prop \"" + prop_name +
	"\" owned by platform cannot have vendor. or odm. namespace";
	return false;
	}
	break;
	case sysprop::Vendor:
	if (!std::regex_match(prop_name, vendor_regex)) {
	if (err)
	*err = "Prop \"" + prop_name +
	"\" owned by vendor should have vendor. namespace";
	return false;
	}
	break;
	case sysprop::Odm:
	if (!std::regex_match(prop_name, odm_regex)) {
	if (err)
	*err = "Prop \"" + prop_name +
	"\" owned by odm should have odm. namespace";
	return false;
	}
	break;
	default:
	break;
	}

	switch (prop.access()) {
	case sysprop::ReadWrite:
	if (android::base::StartsWith(prop_name, "ro.")) {
	if (err) {
	*err = "Prop \"" + prop_name +
	"\" is ReadWrite and also have prefix \"ro.\"";
	}
	return false;
	}
	break;
	default:
	/*
	* TODO: Some properties don't have prefix "ro." but not written in any
	* Java or C++ codes. They might be misnamed and should be readonly. Will
	* uncomment this check after fixing them all / or making a whitelist for
	* them
	if (!android::base::StartsWith(prop_name, "ro.")) {
	if (err) {
	*err = "Prop \"" + prop_name +
	"\" isn't ReadWrite, but don't have prefix \"ro.\"";
	}
	return false;
	}
	*/
	break;
	}

	return true;
	}

	bool ValidateProps(const sysprop::Properties& props, std::string* err) {
	std::vector<std::string> names = android::base::Split(props.module(), ".");
	if (names.size() <= 1) {
	if (err) *err = "Invalid module name \"" + props.module() + "\"";
	return false;
	}

	for (const auto& name : names) {
	if (!IsCorrectIdentifier(name)) {
	if (err) *err = "Invalid name \"" + name + "\" in module";
	return false;
	}
	}

	if (props.prop_size() == 0) {
	if (err) *err = "There is no defined property";
	return false;
	}

	for (int i = 0; i < props.prop_size(); ++i) {
	const auto& prop = props.prop(i);
	if (!ValidateProp(props, prop, err)) return false;
	}

	std::unordered_set<std::string> prop_names;

	for (int i = 0; i < props.prop_size(); ++i) {
	const auto& prop = props.prop(i);
	auto res = prop_names.insert(ApiNameToIdentifier(prop.api_name()));

	if (!res.second) {
	if (err) *err = "Duplicated API name \"" + prop.api_name() + "\"";
	return false;
	}
	}

	return true;
	}

	} // namespace

	// For directory functions, we could use <filesystem> of C++17 if supported..
	bool CreateDirectories(const std::string& path) {
	struct stat st;

	// If already exists..
	if (stat(path.c_str(), &st) == 0) {
	return false;
	}

	size_t last_slash = path.rfind('/');
	if (last_slash > 0 && last_slash != std::string::npos) {
	std::string parent = path.substr(0, last_slash);
	if (!IsDirectory(parent) && !CreateDirectories(parent)) return false;
	}

	// It's very unlikely, but if path contains ".." or any symbolic links, it
	// might already be created before this line.
	return mkdir(path.c_str(), 0755) == 0 \|\| IsDirectory(path);
	}

	bool IsDirectory(const std::string& path) {
	struct stat st;

	if (stat(path.c_str(), &st) == -1) return false;
	return S_ISDIR(st.st_mode);
	}

	bool IsListProp(const sysprop::Property& prop) {
	switch (prop.type()) {
	case sysprop::BooleanList:
	case sysprop::IntegerList:
	case sysprop::LongList:
	case sysprop::DoubleList:
	case sysprop::StringList:
	case sysprop::EnumList:
	return true;
	default:
	return false;
	}
	}

	std::string GetModuleName(const sysprop::Properties& props) {
	const std::string& module = props.module();
	return module.substr(module.rfind('.') + 1);
	}

	bool ParseProps(const std::string& input_file_path, sysprop::Properties* props,
	std::string* err) {
	std::string file_contents;

	if (!android::base::ReadFileToString(input_file_path, &file_contents, true)) {
	*err = "Error reading file " + input_file_path + ": " + strerror(errno);
	return false;
	}

	if (!google::protobuf::TextFormat::ParseFromString(file_contents, props)) {
	*err = "Error parsing file " + input_file_path;
	return false;
	}

	if (!ValidateProps(*props, err)) {
	return false;
	}

	for (int i = 0; i < props->prop_size(); ++i) {
	// set each optional field to its default value
	sysprop::Property& prop = *props->mutable_prop(i);
	if (prop.prop_name().empty())
	prop.set_prop_name(GenerateDefaultPropName(*props, prop));
	}

	return true;
	}

	std::string ToUpper(std::string str) {
	for (char& ch : str) {
	ch = toupper(ch);
	}
	return str;
	}

	std::string ApiNameToIdentifier(const std::string& name) {
	static const std::regex kRegexAllowed{"-\|\\."};
	return (isdigit(name[0]) ? "_" : "") +
	std::regex_replace(name, kRegexAllowed, "_");
	}