feat(ll-cli): add subcommand 'inspect'

Signed-off-by: ComixHe <[email protected]>

api/schema/v1.json

@@ -2,6 +2,16 @@
   "$schema": "http://json-schema.org/draft-04/schema#",
   "description": "Types used as v1 API of linglong D-Bus service, configuration files and CLI output. The top level type is a place holder to make quicktype work.",
   "$defs": {
+    "InspectResult": {
+      "description": "the result of inspecting a container",
+      "type": "object",
+      "properties": {
+        "appID": {
+          "type": "string",
+          "description": "appID of container"
+        }
+      }
+    },
     "ApplicationConfiguration": {
       "title": "ApplicationConfiguration",
       "description": "application configuration",
@@ -1147,6 +1157,9 @@
   },
   "type": "object",
   "properties": {
+    "InspectResult": {
+      "$ref": "#/$defs/InspectResult"
+    },
     "ApplicationConfiguration": {
       "$ref": "#/$defs/ApplicationConfiguration"
     },

api/schema/v1.yaml

@@ -21,6 +21,13 @@ description: Types used as v1 API of linglong
   D-Bus service, configuration files and CLI output.
   The top level type is a place holder to make quicktype work.
 $defs:
+  InspectResult:
+    description: the result of inspecting a container
+    type: object
+    properties:
+      appID:
+        type: string
+        description: appID of container
   ApplicationConfiguration:
     title: ApplicationConfiguration
     description: application configuration

apps/ll-cli/src/main.cpp

@@ -500,6 +500,31 @@ ll-cli list --upgradable
       ->group(CliAppManagingGroup)
       ->usage(_("Usage: ll-cli prune [OPTIONS]"));
 
+    // add sub command inspect
+    auto *cliInspect =
+      commandParser
+        .add_subcommand("inspect", _("Display the information of installed application"))
+        ->group(CliHiddenGroup)
+        ->usage(_("Usage: ll-cli inspect [OPTIONS]"));
+    cliInspect->footer("This subcommand is for internal use only currently");
+    cliInspect->add_option("-p,--pid", options.pid, _("Specify the process id"))
+      ->check([](const std::string &input) -> std::string {
+          if (input.empty()) {
+              return _("Input parameter is empty, please input valid parameter instead");
+          }
+
+          try {
+              auto pid = std::stoull(input);
+              if (pid <= 0) {
+                  return _("Invalid process id");
+              }
+          } catch (std::exception &e) {
+              return _("Invalid pid format");
+          }
+
+          return {};
+      });
+
     auto res = transformOldExec(argc, argv);
     std::reverse(res.begin(), res.end());
     CLI11_PARSE(commandParser, res);
@@ -679,7 +704,8 @@ ll-cli list --upgradable
               { "list", &Cli::list },
               { "info", &Cli::info },
               { "content", &Cli::content },
-              { "prune", &Cli::prune }
+              { "prune", &Cli::prune },
+              { "inspect", &Cli::inspect }
           };
 
           if (QObject::connect(QCoreApplication::instance(),

libs/api/src/linglong/api/types/v1/Generators.hpp

@@ -49,6 +49,7 @@
 #include "linglong/api/types/v1/InteractionRequest.hpp"
 #include "linglong/api/types/v1/InteractionReply.hpp"
 #include "linglong/api/types/v1/InteractionMessageType.hpp"
+#include "linglong/api/types/v1/InspectResult.hpp"
 #include "linglong/api/types/v1/DialogMessage.hpp"
 #include "linglong/api/types/v1/DialogHandShakePayload.hpp"
 #include "linglong/api/types/v1/ContainerProcessStateInfo.hpp"
@@ -122,6 +123,9 @@ void to_json(json & j, const DialogHandShakePayload & x);
 void from_json(const json & j, DialogMessage & x);
 void to_json(json & j, const DialogMessage & x);
 
+void from_json(const json & j, InspectResult & x);
+void to_json(json & j, const InspectResult & x);
+
 void from_json(const json & j, InteractionReply & x);
 void to_json(json & j, const InteractionReply & x);
 
@@ -503,6 +507,17 @@ j["payload"] = x.payload;
 j["type"] = x.type;
 }
 
+inline void from_json(const json & j, InspectResult& x) {
+x.appID = get_stack_optional<std::string>(j, "appID");
+}
+
+inline void to_json(json & j, const InspectResult & x) {
+j = json::object();
+if (x.appID) {
+j["appID"] = x.appID;
+}
+}
+
 inline void from_json(const json & j, InteractionReply& x) {
 x.action = get_stack_optional<std::string>(j, "action");
 }
@@ -970,6 +985,7 @@ x.commonResult = get_stack_optional<CommonResult>(j, "CommonResult");
 x.containerProcessStateInfo = get_stack_optional<ContainerProcessStateInfo>(j, "ContainerProcessStateInfo");
 x.dialogHandShakePayload = get_stack_optional<DialogHandShakePayload>(j, "DialogHandShakePayload");
 x.dialogMessage = get_stack_optional<DialogMessage>(j, "DialogMessage");
+x.inspectResult = get_stack_optional<InspectResult>(j, "InspectResult");
 x.interactionMessageType = get_stack_optional<InteractionMessageType>(j, "InteractionMessageType");
 x.interactionReply = get_stack_optional<InteractionReply>(j, "InteractionReply");
 x.interactionRequest = get_stack_optional<InteractionRequest>(j, "InteractionRequest");
@@ -1034,6 +1050,9 @@ j["DialogHandShakePayload"] = x.dialogHandShakePayload;
 if (x.dialogMessage) {
 j["DialogMessage"] = x.dialogMessage;
 }
+if (x.inspectResult) {
+j["InspectResult"] = x.inspectResult;
+}
 if (x.interactionMessageType) {
 j["InteractionMessageType"] = x.interactionMessageType;
 }

libs/api/src/linglong/api/types/v1/InspectResult.hpp

@@ -0,0 +1,44 @@
+// This file is generated by tools/codegen.sh
+// DO NOT EDIT IT.
+
+// clang-format off
+
+//  To parse this JSON data, first install
+//
+//      json.hpp  https://github.com/nlohmann/json
+//
+//  Then include this file, and then do
+//
+//     InspectResult.hpp data = nlohmann::json::parse(jsonString);
+
+#pragma once
+
+#include <optional>
+#include <nlohmann/json.hpp>
+#include "linglong/api/types/v1/helper.hpp"
+
+namespace linglong {
+namespace api {
+namespace types {
+namespace v1 {
+/**
+* the result of inspecting a container
+*/
+
+using nlohmann::json;
+
+/**
+* the result of inspecting a container
+*/
+struct InspectResult {
+/**
+* appID of container
+*/
+std::optional<std::string> appID;
+};
+}
+}
+}
+}
+
+// clang-format on

libs/api/src/linglong/api/types/v1/LinglongAPIV1.hpp

@@ -28,6 +28,7 @@
 #include "linglong/api/types/v1/ContainerProcessStateInfo.hpp"
 #include "linglong/api/types/v1/DialogHandShakePayload.hpp"
 #include "linglong/api/types/v1/DialogMessage.hpp"
+#include "linglong/api/types/v1/InspectResult.hpp"
 #include "linglong/api/types/v1/InteractionReply.hpp"
 #include "linglong/api/types/v1/InteractionRequest.hpp"
 #include "linglong/api/types/v1/LayerInfo.hpp"
@@ -90,6 +91,7 @@ std::optional<CommonResult> commonResult;
 std::optional<ContainerProcessStateInfo> containerProcessStateInfo;
 std::optional<DialogHandShakePayload> dialogHandShakePayload;
 std::optional<DialogMessage> dialogMessage;
+std::optional<InspectResult> inspectResult;
 std::optional<InteractionMessageType> interactionMessageType;
 std::optional<InteractionReply> interactionReply;
 std::optional<InteractionRequest> interactionRequest;

libs/linglong/src/linglong/cli/cli.cpp

@@ -39,6 +39,7 @@
 #include <QEventLoop>
 #include <QFileInfo>
 
+#include <charconv>
 #include <cstdlib>
 #include <filesystem>
 #include <iostream>
@@ -56,6 +57,91 @@ static const std::string permissionNotifyMsg =
 
 namespace {
 
+linglong::utils::error::Result<bool> isChildProcess(pid_t parent, pid_t pid) noexcept
+{
+    LINGLONG_TRACE(QString{ "check if %1 is child of %2" }.arg(pid).arg(parent));
+
+    auto getppid = [](pid_t pid) -> Result<pid_t> {
+        LINGLONG_TRACE(QString{ "get ppid of %1" }.arg(pid));
+        std::error_code ec;
+        auto stat = std::filesystem::path("/proc/" + std::to_string(pid) + "/stat");
+        auto fd = ::open(stat.c_str(), O_RDONLY);
+        if (fd == -1) {
+            return LINGLONG_ERR(
+              QString{ "failed to open %1: %2" }.arg(stat.c_str(), ::strerror(errno)));
+        }
+        auto closeFd = linglong::utils::finally::finally([fd] {
+            ::close(fd);
+        });
+
+        // FIXME: Parsing /proc/pid/stat isn't an good idea, the consistency of file contents
+        // which in /proc is not guaranteed and the format may change. so we read all the content at
+        // first and then parse it.
+        // use read instead of std::ifstream to get more detailed error information the size
+        // of /proc/pid/stat is zero and we can't get the content size by stat,
+        // so we use 1024 as the buffer size.
+        std::array<char, 1024> buf{};
+        std::string content;
+        while (true) {
+            auto readBytes = ::read(fd, buf.data(), buf.size());
+            if (readBytes == -1) {
+                return LINGLONG_ERR(
+                  QString{ "failed to read from %1: %2" }.arg(stat.c_str(), ::strerror(errno)));
+            }
+
+            if (readBytes == 0) {
+                break;
+            }
+
+            content.append(buf.data(), readBytes);
+        }
+
+        auto ppidOffset = 3;
+        auto left = 0;
+        auto right = 0;
+        for (int i = 0; i < content.size(); i++) {
+            if (ppidOffset == 0) {
+                left = i;
+                right = i;
+
+                while (content[right] != ' ') {
+                    right += 1;
+                }
+
+                break;
+            }
+
+            if (content[i] == ' ') {
+                ppidOffset -= 1;
+            }
+        }
+
+        pid_t ppid{ -1 };
+        auto [_, err] = std::from_chars(content.c_str() + left, content.c_str() + right, ppid);
+        if (err != std::errc()) {
+            return LINGLONG_ERR(QString{ "failed to parse %1: %2" }.arg(
+              std::string_view(content.c_str() + left, right - left).data(),
+              ::strerror(static_cast<int>(err))));
+        }
+
+        return ppid;
+    };
+
+    while (pid != parent) {
+        auto ppid = getppid(pid);
+        if (!ppid) {
+            return LINGLONG_ERR(ppid.error());
+        }
+
+        pid = *ppid;
+        if (pid < parent) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
 linglong::utils::error::Result<void> ensureDirectory(const std::filesystem::path &dir)
 {
     LINGLONG_TRACE("ensure runtime directory");
@@ -2454,4 +2540,36 @@ void Cli::updateAM() noexcept
         }
     }
 }
+
+int Cli::inspect()
+{
+    auto myContainersRet = getCurrentContainers();
+    if (!myContainersRet) {
+        this->printer.printErr(myContainersRet.error());
+        return -1;
+    }
+    const auto &myContainers = *myContainersRet;
+
+    api::types::v1::InspectResult result;
+
+    if (this->options.pid) {
+        qDebug() << "inspect by pid:" << this->options.pid.value();
+        for (const auto &container : myContainers) {
+            auto ret = isChildProcess(container.pid, this->options.pid.value());
+            if (!ret) {
+                this->printer.printErr(ret.error());
+                return -1;
+            }
+
+            if (*ret) {
+                result.appID = container.package;
+                break;
+            }
+        }
+    }
+
+    this->printer.printInspect(result);
+    return 0;
+}
+
 } // namespace linglong::cli

libs/linglong/src/linglong/cli/cli.h

@@ -20,6 +20,7 @@ namespace linglong::cli {
 
 class Printer;
 
+// TODO: split this into multiple options
 struct CliOptions
 {
     std::vector<std::string> filePaths;
@@ -36,6 +37,7 @@ struct CliOptions
     bool showUpgradeList;
     bool forceOpt;
     bool confirmOpt;
+    std::optional<pid_t> pid;
 };
 
 class Cli : public QObject
@@ -69,6 +71,7 @@ class Cli : public QObject
     int info();
     int content();
     int prune();
+    int inspect();
 
     void cancelCurrentTask();
 

libs/linglong/src/linglong/cli/cli_printer.cpp

@@ -199,4 +199,10 @@ void CLIPrinter::printUpgradeList(std::vector<api::types::v1::UpgradeListResult>
     }
 }
 
+void CLIPrinter::printInspect(const api::types::v1::InspectResult &result)
+{
+    std::cout << "appID:\t" << (result.appID.has_value() ? result.appID.value() : "none")
+              << std::endl;
+}
+
 } // namespace linglong::cli

libs/linglong/src/linglong/cli/cli_printer.h

@@ -29,7 +29,7 @@ class CLIPrinter : public Printer
     CLIPrinter(CLIPrinter &&) = delete;
     CLIPrinter &operator=(const CLIPrinter &) = delete;
     CLIPrinter &operator=(CLIPrinter &&) = delete;
-    ~CLIPrinter() = default;
+    ~CLIPrinter() override = default;
 
     void printErr(const utils::error::Error &) override;
     void printPackage(const api::types::v1::PackageInfoV2 &) override;
@@ -45,6 +45,7 @@ class CLIPrinter : public Printer
                         api::types::v1::SubState subState) override;
     void printContent(const QStringList &filePaths) override;
     void printUpgradeList(std::vector<api::types::v1::UpgradeListResult> &) override;
+    void printInspect(const api::types::v1::InspectResult &result) override;
 };
 
 } // namespace linglong::cli

libs/linglong/src/linglong/cli/json_printer.cpp

@@ -83,4 +83,9 @@ void JSONPrinter::printUpgradeList(std::vector<api::types::v1::UpgradeListResult
     std::cout << nlohmann::json(list).dump(4) << std::endl;
 }
 
+void JSONPrinter::printInspect(const api::types::v1::InspectResult &result)
+{
+    std::cout << nlohmann::json(result).dump(4) << std::endl;
+}
+
 } // namespace linglong::cli