From 4e2e5ad002481caeb608205b9c9c7a95d6045563 Mon Sep 17 00:00:00 2001
From: Evil Eye <malusluminis@hotmail.com>
Date: Wed, 24 Aug 2022 23:10:05 +0200
Subject: [PATCH] Revert format change and ensure string_view args are
 null-terminated

---
 apps/openmw/mwgui/spellwindow.cpp    |  3 ++-
 apps/openmw/mwmechanics/npcstats.cpp |  4 ++--
 components/misc/strings/format.hpp   | 20 +++++++++++++-------
 3 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/apps/openmw/mwgui/spellwindow.cpp b/apps/openmw/mwgui/spellwindow.cpp
index f5618abafb..c39341aeb4 100644
--- a/apps/openmw/mwgui/spellwindow.cpp
+++ b/apps/openmw/mwgui/spellwindow.cpp
@@ -168,7 +168,8 @@ namespace MWGui
             // ask for confirmation
             mSpellToDelete = spellId;
             ConfirmationDialog* dialog = windowManager->getConfirmationDialog();
-            std::string question = Misc::StringUtils::format(windowManager->getGameSettingString("sQuestionDeleteSpell", "Delete %s?"), spell->mName);
+            std::string question{windowManager->getGameSettingString("sQuestionDeleteSpell", "Delete %s?")};
+            question = Misc::StringUtils::format(question, spell->mName);
             dialog->askForConfirmation(question);
             dialog->eventOkClicked.clear();
             dialog->eventOkClicked += MyGUI::newDelegate(this, &SpellWindow::onDeleteSpellAccept);
diff --git a/apps/openmw/mwmechanics/npcstats.cpp b/apps/openmw/mwmechanics/npcstats.cpp
index 89b10b2bf0..a89e01259c 100644
--- a/apps/openmw/mwmechanics/npcstats.cpp
+++ b/apps/openmw/mwmechanics/npcstats.cpp
@@ -267,8 +267,8 @@ void MWMechanics::NpcStats::increaseSkill(int skillIndex, const ESM::Class &clas
     /// \todo check if character is the player, if levelling is ever implemented for NPCs
     MWBase::Environment::get().getWindowManager()->playSound("skillraise");
 
-    std::string message = Misc::StringUtils::format(MWBase::Environment::get().getWindowManager()->getGameSettingString("sNotifyMessage39", {}),
-        ("#{" + ESM::Skill::sSkillNameIds[skillIndex] + "}"), static_cast<int>(base));
+    std::string message{MWBase::Environment::get().getWindowManager()->getGameSettingString("sNotifyMessage39", {})};
+    message = Misc::StringUtils::format(message, ("#{" + ESM::Skill::sSkillNameIds[skillIndex] + "}"), static_cast<int>(base));
 
     if (readBook)
         message = "#{sBookSkillMessage}\n" + message;
diff --git a/components/misc/strings/format.hpp b/components/misc/strings/format.hpp
index 4104082e63..7b5de50fb4 100644
--- a/components/misc/strings/format.hpp
+++ b/components/misc/strings/format.hpp
@@ -7,11 +7,14 @@
 #include <string>
 #include <string_view>
 #include <stdexcept>
+#include <vector>
 
 namespace Misc::StringUtils
 {
-    namespace Details
+    struct Details
     {
+        std::vector<std::string> mMemorySafety;
+
         // Allow to convert complex arguments to C-style strings for format() function
         template <typename T>
         T argument(T value) noexcept
@@ -22,7 +25,9 @@ namespace Misc::StringUtils
         template <typename T>
         T const * argument(std::basic_string_view<T> const & value) noexcept
         {
-            return value.data();
+            // TODO: switch to a format function that doesn't require null termination
+            auto& inserted = mMemorySafety.emplace_back(value);
+            return inserted.c_str();
         }
 
         template <typename T>
@@ -30,7 +35,7 @@ namespace Misc::StringUtils
         {
             return value.c_str();
         }
-    }
+    };
 
     // Requires some C++11 features:
     // 1. std::string needs to be contiguous
@@ -39,21 +44,22 @@ namespace Misc::StringUtils
     template <typename ... Args>
     std::string format(const char* fmt, Args const & ... args)
     {
-        const int size = std::snprintf(nullptr, 0, fmt, Details::argument(args) ...);
+        Details details;
+        const int size = std::snprintf(nullptr, 0, fmt, details.argument(args) ...);
         if (size < 0)
             throw std::runtime_error(std::string("Failed to compute resulting string size: ") + std::strerror(errno));
         // Note: sprintf also writes a trailing null character. We should remove it.
         std::string ret(static_cast<std::size_t>(size) + 1, '\0');
-        if (std::sprintf(ret.data(), fmt, Details::argument(args) ...) < 0)
+        if (std::sprintf(ret.data(), fmt, details.argument(args) ...) < 0)
             throw std::runtime_error(std::string("Failed to format string: ") + std::strerror(errno));
         ret.erase(static_cast<std::size_t>(size));
         return ret;
     }
 
     template <typename ... Args>
-    std::string format(std::string_view fmt, Args const & ... args)
+    std::string format(const std::string& fmt, Args const & ... args)
     {
-        return format(fmt.data(), args ...);
+        return format(fmt.c_str(), args ...);
     }
 }