vrclient: Introduce unix-side buffer cache with PE allocate pointers.

There are several steam API calls that currently pass unix pointers
for e.g. strings directly to the PE-side, this allows for caching such
return values and returning a PE-side pointer instead.

vrclient_x64/gen_wrapper.py

@@ -223,6 +223,7 @@ unique_structs = []
 UNIX_FUNCS = [
     'vrclient_init',
     'vrclient_init_registry',
+    'vrclient_get_unix_buffer',
     'vrclient_HmdSystemFactory',
     'vrclient_VRClientCoreFactory',
     'vrclient_unload',

vrclient_x64/unix_private.h

@@ -30,6 +30,7 @@ extern NTSTATUS vrclient_init_registry( void *args );
 extern NTSTATUS vrclient_unload( void *args );
 extern NTSTATUS vrclient_HmdSystemFactory( void *args );
 extern NTSTATUS vrclient_VRClientCoreFactory( void *args );
+extern NTSTATUS vrclient_get_unix_buffer( void *args );
 
 extern char *vrclient_dos_to_unix_path( const char *src );
 extern void vrclient_free_path( char *path );

vrclient_x64/unixlib.cpp

@@ -2,7 +2,9 @@
 
 #include <winternl.h>
 #include <dlfcn.h>
+#include <pthread.h>
 #include <stdlib.h>
+#include <unordered_map>
 
 #define WINE_VK_HOST
 #include <vulkan/vulkan.h>
@@ -370,3 +372,35 @@ NTSTATUS IVRTrackedCamera_IVRTrackedCamera_001_GetVideoStreamFrame( void *args )
     *(w_CameraVideoStreamFrame_t_0914 *)params->_ret = *iface->GetVideoStreamFrame( params->nDeviceIndex );
     return 0;
 }
+
+namespace std
+{
+template<> struct hash< struct u_buffer >
+{
+    using argument_type = struct u_buffer;
+    using result_type = std::size_t;
+    result_type operator()( argument_type const& buf ) const { return buf.ptr; }
+};
+}
+
+static pthread_mutex_t buffer_cache_lock = PTHREAD_MUTEX_INITIALIZER;
+static std::unordered_map< struct u_buffer, void * > buffer_cache;
+
+NTSTATUS vrclient_get_unix_buffer( void *args )
+{
+    struct vrclient_get_unix_buffer_params *params = (struct vrclient_get_unix_buffer_params *)args;
+    struct cache_entry *entry;
+    struct rb_entry *ptr;
+
+    pthread_mutex_lock( &buffer_cache_lock );
+    auto iter = buffer_cache.find( params->buf );
+    if (iter != buffer_cache.end()) params->ptr = iter->second;
+    else
+    {
+        memcpy( params->ptr, (char *)params->buf, params->buf.len );
+        buffer_cache[params->buf] = params->ptr;
+    }
+    pthread_mutex_unlock( &buffer_cache_lock );
+
+    return 0;
+}

vrclient_x64/unixlib.h

@@ -73,6 +73,12 @@ struct vrclient_VRClientCoreFactory_params
     int *return_code;
 };
 
+struct vrclient_get_unix_buffer_params
+{
+    struct u_buffer buf;
+    void *ptr; /* client-side ptr */
+};
+
 #include <poppack.h>
 
 #define VRCLIENT_CALL( code, args )                                        \

vrclient_x64/unixlib_generated.cpp

@@ -9,6 +9,7 @@ extern "C" const unixlib_entry_t __wine_unix_call_funcs[] =
 {
     vrclient_init,
     vrclient_init_registry,
+    vrclient_get_unix_buffer,
     vrclient_HmdSystemFactory,
     vrclient_VRClientCoreFactory,
     vrclient_unload,

vrclient_x64/unixlib_generated.h

@@ -29223,6 +29223,7 @@ enum unix_funcs
 {
     unix_vrclient_init,
     unix_vrclient_init_registry,
+    unix_vrclient_get_unix_buffer,
     unix_vrclient_HmdSystemFactory,
     unix_vrclient_VRClientCoreFactory,
     unix_vrclient_unload,

vrclient_x64/vrclient_main.c

@@ -314,6 +314,24 @@ BOOL CDECL vrclient_init_registry(void)
     return TRUE;
 }
 
+void *get_unix_buffer( struct u_buffer buf )
+{
+    struct vrclient_get_unix_buffer_params params = {.buf = buf};
+    void *ret;
+
+    if ((UINT_PTR)buf.ptr == buf.ptr && (UINT_PTR)(buf.ptr + buf.len) == (buf.ptr + buf.len))
+        return (void *)(UINT_PTR)buf.ptr;
+
+    if (!(params.ptr = ret = HeapAlloc( GetProcessHeap(), 0, buf.len ))) return NULL;
+    if (VRCLIENT_CALL( vrclient_get_unix_buffer, &params ) || (ret != params.ptr))
+    {
+        HeapFree( GetProcessHeap(), 0, ret );
+        ret = params.ptr;
+    }
+
+    return ret;
+}
+
 static int8_t is_hmd_present_reg(void)
 {
     DWORD type, value, wait_status, size;

vrclient_x64/vrclient_private.h

@@ -104,6 +104,8 @@ extern void init_rtti( char *base );
 struct w_iface *create_win_interface( const char *name, struct u_iface u_iface );
 void free_compositor_data_d3d12_device(void);
 
+extern void *get_unix_buffer( struct u_buffer buf );
+
 struct generic_interface
 {
     struct w_iface *object;

vrclient_x64/vrclient_structs.h

@@ -134,3 +134,13 @@ struct u_iface
     template< typename T > operator T*() const { return (T*)(UINT_PTR)this->handle; }
 #endif /* __cplusplus */
 };
+
+struct u_buffer
+{
+    UINT64 ptr;
+    UINT64 len;
+#ifdef __cplusplus
+    struct u_buffer &operator=(const char* value) { this->ptr = (UINT_PTR)value; this->len = value ? strlen( value ) + 1 : 0; return *this; }
+    operator char*() const { return (char*)(UINT_PTR)this->ptr; }
+#endif /* __cplusplus */
+};