windows: directsound should also map audio device GUIDs to proper names.

Moved this code from winmm into core so both can use it.

DirectSound (at least on Win10) also returns truncated device names, even
though it's handed in as a string pointer and not a static-sized buffer.  :/

src/audio/directsound/SDL_directsound.c

@@ -155,7 +155,7 @@ FindAllDevs(LPGUID guid, LPCWSTR desc, LPCWSTR module, LPVOID data)
 {
     const int iscapture = (int) ((size_t) data);
     if (guid != NULL) {  /* skip default device */
-        char *str = WIN_StringToUTF8(desc);
+        char *str = WIN_LookupAudioDeviceName(desc, guid);
         if (str != NULL) {
             LPGUID cpyguid = (LPGUID) SDL_malloc(sizeof (GUID));
             SDL_memcpy(cpyguid, guid, sizeof (GUID));

src/audio/winmm/SDL_winmm.c

@@ -37,77 +37,6 @@
 #define WAVE_FORMAT_IEEE_FLOAT 0x0003
 #endif
 
-/*
-WAVExxxCAPS gives you 31 bytes for the device name, and just truncates if it's
-longer. However, since WinXP, you can use the WAVExxxCAPS2 structure, which
-will give you a name GUID. The full name is in the Windows Registry under
-that GUID, located here: HKLM\System\CurrentControlSet\Control\MediaCategories
-
-Note that drivers can report GUID_NULL for the name GUID, in which case,
-Windows makes a best effort to fill in those 31 bytes in the usual place.
-This info summarized from MSDN:
-
-http://web.archive.org/web/20131027093034/http://msdn.microsoft.com/en-us/library/windows/hardware/ff536382(v=vs.85).aspx
-
-Always look this up in the registry if possible, because the strings are
-different! At least on Win10, I see "Yeti Stereo Microphone" in the
-Registry, and a unhelpful "Microphone(Yeti Stereo Microph" in winmm. Sigh.
-*/
-static char *
-LookupDeviceName(const WCHAR *name, const GUID *guid)
-{
-    static const GUID nullguid = { 0 };
-    const unsigned char *ptr;
-    char keystr[128];
-    WCHAR *strw = NULL;
-    SDL_bool rc;
-    HKEY hkey;
-    DWORD len = 0;
-    char *retval = NULL;
-
-    if (SDL_memcmp(guid, &nullguid, sizeof (*guid)) == 0) {
-        return WIN_StringToUTF8(name);  /* No GUID, go with what we've got. */
-    }
-
-    ptr = (const char *) guid;
-    SDL_snprintf(keystr, sizeof (keystr),
-        "System\\CurrentControlSet\\Control\\MediaCategories\\{%02X%02X%02X%02X-%02X%02X-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X}",
-        ptr[3], ptr[2], ptr[1], ptr[0], ptr[5], ptr[4], ptr[7], ptr[6],
-        ptr[8], ptr[9], ptr[10], ptr[11], ptr[12], ptr[13], ptr[14], ptr[15]);
-
-    strw = WIN_UTF8ToString(keystr);
-    rc = (RegOpenKeyExW(HKEY_LOCAL_MACHINE, strw, 0, KEY_QUERY_VALUE, &hkey) == ERROR_SUCCESS);
-    SDL_free(strw);
-    if (!rc) {
-        return WIN_StringToUTF8(name);  /* oh well. */
-    }
-
-    rc = (RegQueryValueExW(hkey, L"Name", NULL, NULL, NULL, &len) == ERROR_SUCCESS);
-    if (!rc) {
-        RegCloseKey(hkey);
-        return WIN_StringToUTF8(name);  /* oh well. */
-    }
-
-    strw = (WCHAR *) SDL_malloc(len + sizeof (WCHAR));
-    if (!strw) {
-        RegCloseKey(hkey);
-        return WIN_StringToUTF8(name);  /* oh well. */
-    }
-
-    rc = (RegQueryValueExW(hkey, L"Name", NULL, NULL, (LPBYTE) strw, &len) == ERROR_SUCCESS);
-    RegCloseKey(hkey);
-    if (!rc) {
-        SDL_free(strw);
-        return WIN_StringToUTF8(name);  /* oh well. */
-    }
-
-    strw[len / 2] = 0;  /* make sure it's null-terminated. */
-
-    retval = WIN_StringToUTF8(strw);
-    SDL_free(strw);
-    return retval ? retval : WIN_StringToUTF8(name);
-}
-
 #define DETECT_DEV_IMPL(iscap, typ, capstyp) \
 static void DetectWave##typ##Devs(void) { \
     const UINT iscapture = iscap ? 1 : 0; \
@@ -116,7 +45,7 @@ static void DetectWave##typ##Devs(void) { \
     UINT i; \
     for (i = 0; i < devcount; i++) { \
 	if (wave##typ##GetDevCaps(i,(LP##capstyp##W)&caps,sizeof(caps))==MMSYSERR_NOERROR) { \
-            char *name = LookupDeviceName(caps.szPname,&caps.NameGuid); \
+            char *name = WIN_LookupAudioDeviceName(caps.szPname,&caps.NameGuid); \
             if (name != NULL) { \
                 SDL_AddAudioDevice((int) iscapture, name, (void *) ((size_t) i+1)); \
                 SDL_free(name); \

src/core/windows/SDL_windows.c

@@ -124,6 +124,80 @@ BOOL WIN_IsWindowsVistaOrGreater()
 #endif
 }
 
+/*
+WAVExxxCAPS gives you 31 bytes for the device name, and just truncates if it's
+longer. However, since WinXP, you can use the WAVExxxCAPS2 structure, which
+will give you a name GUID. The full name is in the Windows Registry under
+that GUID, located here: HKLM\System\CurrentControlSet\Control\MediaCategories
+
+Note that drivers can report GUID_NULL for the name GUID, in which case,
+Windows makes a best effort to fill in those 31 bytes in the usual place.
+This info summarized from MSDN:
+
+http://web.archive.org/web/20131027093034/http://msdn.microsoft.com/en-us/library/windows/hardware/ff536382(v=vs.85).aspx
+
+Always look this up in the registry if possible, because the strings are
+different! At least on Win10, I see "Yeti Stereo Microphone" in the
+Registry, and a unhelpful "Microphone(Yeti Stereo Microph" in winmm. Sigh.
+
+(Also, DirectSound shouldn't be limited to 32 chars, but its device enum
+has the same problem.)
+*/
+char *
+WIN_LookupAudioDeviceName(const WCHAR *name, const GUID *guid)
+{
+    static const GUID nullguid = { 0 };
+    const unsigned char *ptr;
+    char keystr[128];
+    WCHAR *strw = NULL;
+    SDL_bool rc;
+    HKEY hkey;
+    DWORD len = 0;
+    char *retval = NULL;
+
+    if (SDL_memcmp(guid, &nullguid, sizeof (*guid)) == 0) {
+        return WIN_StringToUTF8(name);  /* No GUID, go with what we've got. */
+    }
+
+    ptr = (const char *) guid;
+    SDL_snprintf(keystr, sizeof (keystr),
+        "System\\CurrentControlSet\\Control\\MediaCategories\\{%02X%02X%02X%02X-%02X%02X-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X}",
+        ptr[3], ptr[2], ptr[1], ptr[0], ptr[5], ptr[4], ptr[7], ptr[6],
+        ptr[8], ptr[9], ptr[10], ptr[11], ptr[12], ptr[13], ptr[14], ptr[15]);
+
+    strw = WIN_UTF8ToString(keystr);
+    rc = (RegOpenKeyExW(HKEY_LOCAL_MACHINE, strw, 0, KEY_QUERY_VALUE, &hkey) == ERROR_SUCCESS);
+    SDL_free(strw);
+    if (!rc) {
+        return WIN_StringToUTF8(name);  /* oh well. */
+    }
+
+    rc = (RegQueryValueExW(hkey, L"Name", NULL, NULL, NULL, &len) == ERROR_SUCCESS);
+    if (!rc) {
+        RegCloseKey(hkey);
+        return WIN_StringToUTF8(name);  /* oh well. */
+    }
+
+    strw = (WCHAR *) SDL_malloc(len + sizeof (WCHAR));
+    if (!strw) {
+        RegCloseKey(hkey);
+        return WIN_StringToUTF8(name);  /* oh well. */
+    }
+
+    rc = (RegQueryValueExW(hkey, L"Name", NULL, NULL, (LPBYTE) strw, &len) == ERROR_SUCCESS);
+    RegCloseKey(hkey);
+    if (!rc) {
+        SDL_free(strw);
+        return WIN_StringToUTF8(name);  /* oh well. */
+    }
+
+    strw[len / 2] = 0;  /* make sure it's null-terminated. */
+
+    retval = WIN_StringToUTF8(strw);
+    SDL_free(strw);
+    return retval ? retval : WIN_StringToUTF8(name);
+}
+
 #endif /* __WIN32__ || __WINRT__ */
 
 /* vi: set ts=4 sw=4 expandtab: */

src/core/windows/SDL_windows.h

@@ -59,6 +59,9 @@ extern void WIN_CoUninitialize(void);
 /* Returns SDL_TRUE if we're running on Windows Vista and newer */
 extern BOOL WIN_IsWindowsVistaOrGreater();
 
+/* You need to SDL_free() the result of this call. */
+extern char *WIN_LookupAudioDeviceName(const WCHAR *name, const GUID *guid);
+
 #endif /* _INCLUDED_WINDOWS_H */
 
 /* vi: set ts=4 sw=4 expandtab: */