fs: Fix RomFS building when zero byte files are present

When zero byte files are present, the key (offset) for that file is identical to the file right after. A std::map isn't able to fit key-value pairs with identical keys (offsets), therefore, the solution is to use std::multimap which permits multiple entries with the same key.

This most prominently fixes Pokemon Sword and Shield weather with any RomFS mod applied.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/core/file_sys/fsmitm_romfsbuild.cpp b/src/core/file_sys/fsmitm_romfsbuild.cpp
index d126ae8dd..2aff2708a 100644
--- a/src/core/file_sys/fsmitm_romfsbuild.cpp
+++ b/src/core/file_sys/fsmitm_romfsbuild.cpp
@@ -240,7 +240,7 @@ RomFSBuildContext::RomFSBuildContext(VirtualDir base_, VirtualDir ext_)
 
 RomFSBuildContext::~RomFSBuildContext() = default;
 
-std::map<u64, VirtualFile> RomFSBuildContext::Build() {
+std::multimap<u64, VirtualFile> RomFSBuildContext::Build() {
     const u64 dir_hash_table_entry_count = romfs_get_hash_table_count(num_dirs);
     const u64 file_hash_table_entry_count = romfs_get_hash_table_count(num_files);
     dir_hash_table_size = 4 * dir_hash_table_entry_count;
@@ -294,7 +294,7 @@ std::map<u64, VirtualFile> RomFSBuildContext::Build() {
         cur_dir->parent->child = cur_dir;
     }
 
-    std::map<u64, VirtualFile> out;
+    std::multimap<u64, VirtualFile> out;
 
     // Populate file tables.
     for (const auto& it : files) {