IconCache: Expire saved icons after 24 hours

Icons were kept in icon.cache indefinitely, so one that changes on the
server (a RetroAchievements user avatar, keyed by username) never
refreshed. The insertion timestamp was process-relative, so it couldn't
be compared across sessions. Store wall-clock time, and skip entries
older than a day when loading. Bumps the cache version.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

Common/UI/IconCache.cpp

@@ -9,7 +9,8 @@
 #include "Common/GPU/thin3d.h"
 #include "Common/File/FileUtil.h"
 
-#define ICON_CACHE_VERSION 1
+// 2: insertedTimestamp became wall-clock time.
+#define ICON_CACHE_VERSION 2
 #define MK_FOURCC(str) (str[0] | ((uint8_t)str[1] << 8) | ((uint8_t)str[2] << 16) | ((uint8_t)str[3] << 24))
 
 #define MAX_RUNTIME_CACHE_SIZE (1024 * 1024 * 4)
@@ -17,6 +18,8 @@
 
 // Seconds before MarkPending accepts a key whose download failed.
 constexpr double FAILED_RETRY_DELAY = 30.0;
+// Seconds a saved icon is kept across sessions, so that ones that change (user avatars) get refreshed.
+constexpr double MAX_SAVED_ICON_AGE = 24 * 60 * 60.0;
 // Seconds before BindIconTexture tries again to create a texture that failed.
 constexpr double UPLOAD_RETRY_DELAY = 5.0;
 
@@ -91,6 +94,7 @@ bool IconCache::LoadFromFile(FILE *file) {
 	}
 
 	double now = time_now_d();
+	double nowUnix = time_now_unix_utc();
 
 	for (uint32_t i = 0; i < header.entryCount; i++) {
 		DiskCacheEntry entryHeader{};
@@ -110,8 +114,8 @@ bool IconCache::LoadFromFile(FILE *file) {
 			break;
 		}
 
-		// Check if we already have the entry somehow.
-		if (cache_.find(key) != cache_.end()) {
+		// Skip it if we already have the entry somehow, or it's too old.
+		if (cache_.find(key) != cache_.end() || nowUnix - entryHeader.insertedTimestamp > MAX_SAVED_ICON_AGE) {
 			// Seek past the data and go to the next entry.
 			File::Fseek(file, entryHeader.dataLen, SEEK_CUR);
 			continue;
@@ -319,7 +323,7 @@ bool IconCache::InsertIcon(std::string_view key, IconFormat format, std::string
 	}
 
 	double now = time_now_d();
-	Entry entry{ std::move(data), format, nullptr, now, now };
+	Entry entry{ std::move(data), format, nullptr, time_now_unix_utc(), now };
 	PeekIconSize(entry.data, entry.format, &entry.width, &entry.height);
 	cache_.emplace(key, std::move(entry));
 	return true;

Common/UI/IconCache.h

@@ -60,7 +60,7 @@ private:
 		std::string data;
 		IconFormat format;
 		Draw::Texture *texture;
-		double insertedTimeStamp;
+		double insertedTimeStamp;  // Wall-clock (time_now_unix_utc), since it's saved.
 		double usedTimeStamp;
 		double uploadFailedTime;  // When CreateTexture last failed, or 0.
 		int width;  // From the image header, 0 if unknown.