nt-lite/code/user/system/rssrv/display.c

// RSSRV display authority. This component owns session display metadata, modeset, and transitional console authority.

#include "rssrv_internal.h"
#include <string.h>

// Initializes RSSRV display authority from the attenuated bootstrap manager capability.
KSTATUS RssrvDisplayInitialize(RSSRV_DISPLAY_STATE* display, RSSRV_NAMESPACE* namespaceState, SYS_HANDLE manager) {
    if (!display || !namespaceState || manager == SYS_HANDLE_INVALID)
        return NTLSTATUS_INVALID_PARAMETER;
    memset(display, 0, sizeof(*display));
    display->Manager = manager;
    display->Namespace = namespaceState;
    return NTLSTATUS_SUCCESS;
}

// Publishes read-only display metadata while keeping mode and transitional console authority private to RSSRV.
KSTATUS RssrvDisplayPublishDevice(RSSRV_DISPLAY_STATE* display) {
    if (!display || !display->Namespace || display->Manager == SYS_HANDLE_INVALID)
        return NTLSTATUS_INVALID_PARAMETER;

    SYS_HANDLE deviceHandle = SYS_HANDLE_INVALID;
    SYS_DERIVE_HANDLE_REQUEST derive;
    memset(&derive, 0, sizeof(derive));
    derive.Size = sizeof(derive);
    derive.SourceHandle = display->Manager;
    derive.DesiredRights = SYS_RIGHT_TRANSFER | SYS_RIGHT_QUERY | SYS_DISPLAY_MANAGER_RIGHT_ENUMERATE;
    derive.DerivedHandleOut = &deviceHandle;
    KSTATUS status = SysDeriveHandle(&derive);
    if (!KSUCCESS(status)) return status;

    status = RssrvNamespaceBindOwned(display->Namespace,
                                     "/Device/Display0",
                                     sizeof("/Device/Display0") - 1u,
                                     NTL_RESOURCE_KIND_DEVICE,
                                     deviceHandle,
                                     SYS_RIGHT_QUERY | SYS_DISPLAY_MANAGER_RIGHT_ENUMERATE);
    if (!KSUCCESS(status)) (void)SysCloseHandle(deviceHandle);
    return status;
}

// Queries the primary display through RSSRV's delegated manager capability.
KSTATUS RssrvDisplayQueryInfo(RSSRV_DISPLAY_STATE* display, SYS_DISPLAY_INFO* infoOut) {
    if (!display || display->Manager == SYS_HANDLE_INVALID || !infoOut)
        return NTLSTATUS_INVALID_PARAMETER;
    return SysQueryDisplayManagerInfo(display->Manager, infoOut);
}

// Writes text through RSSRV's delegated legacy-console bridge.
KSTATUS RssrvDisplayWriteConsole(RSSRV_DISPLAY_STATE* display, const char* data, size_t length) {
    if (!display || display->Manager == SYS_HANDLE_INVALID || (length && !data))
        return NTLSTATUS_INVALID_PARAMETER;
    SYS_WRITE_CONSOLE_REQUEST request;
    memset(&request, 0, sizeof(request));
    request.Size = sizeof(request);
    request.Text = SysSvFromParts(data, length);
    return SysWriteDisplayManagerConsole(display->Manager, &request);
}

// Queries the kernel-backed console state during the RSSRV migration period.
KSTATUS RssrvDisplayQueryConsoleInfo(RSSRV_DISPLAY_STATE* display, SYS_CONSOLE_INFO* infoOut) {
    if (!display || display->Manager == SYS_HANDLE_INVALID || !infoOut)
        return NTLSTATUS_INVALID_PARAMETER;
    return SysQueryDisplayManagerConsoleInfo(display->Manager, infoOut);
}

// Updates the kernel-backed console cursor through delegated authority.
KSTATUS RssrvDisplaySetConsoleCursor(RSSRV_DISPLAY_STATE* display, int32_t x, int32_t y) {
    if (!display || display->Manager == SYS_HANDLE_INVALID)
        return NTLSTATUS_INVALID_PARAMETER;
    return SysSetDisplayManagerConsoleCursor(display->Manager, x, y);
}

// Fills kernel-backed console characters through delegated authority.
KSTATUS RssrvDisplayFillConsoleCharacter(RSSRV_DISPLAY_STATE* display, char character,
                                         int32_t x, int32_t y, size_t length, size_t* writtenOut) {
    if (!display || display->Manager == SYS_HANDLE_INVALID)
        return NTLSTATUS_INVALID_PARAMETER;
    SYS_FILL_CONSOLE_CHARACTER_REQUEST request;
    memset(&request, 0, sizeof(request));
    request.Size = sizeof(request);
    request.Character = character;
    request.X = x;
    request.Y = y;
    request.Length = length;
    request.WrittenOut = writtenOut;
    return SysFillDisplayManagerConsoleCharacter(display->Manager, &request);
}

// Fills kernel-backed console attributes through delegated authority.
KSTATUS RssrvDisplayFillConsoleAttribute(RSSRV_DISPLAY_STATE* display, uint16_t attribute,
                                         int32_t x, int32_t y, size_t length, size_t* writtenOut) {
    if (!display || display->Manager == SYS_HANDLE_INVALID)
        return NTLSTATUS_INVALID_PARAMETER;
    SYS_FILL_CONSOLE_ATTRIBUTE_REQUEST request;
    memset(&request, 0, sizeof(request));
    request.Size = sizeof(request);
    request.Attribute = attribute;
    request.X = x;
    request.Y = y;
    request.Length = length;
    request.WrittenOut = writtenOut;
    return SysFillDisplayManagerConsoleAttribute(display->Manager, &request);
}

// Draws one explicit glyph through delegated console authority.
KSTATUS RssrvDisplayPutConsoleCharacter(RSSRV_DISPLAY_STATE* display, char character,
                                        int32_t x, int32_t y, uint32_t foreground, uint32_t background) {
    if (!display || display->Manager == SYS_HANDLE_INVALID)
        return NTLSTATUS_INVALID_PARAMETER;
    SYS_PUT_SCREEN_CHAR_REQUEST request;
    memset(&request, 0, sizeof(request));
    request.Size = sizeof(request);
    request.Character = character;
    request.X = x;
    request.Y = y;
    request.Foreground = foreground;
    request.Background = background;
    return SysPutDisplayManagerConsoleCharacter(display->Manager, &request);
}

// Clears the current console target through delegated console authority.
KSTATUS RssrvDisplayClearConsole(RSSRV_DISPLAY_STATE* display, uint32_t color) {
    if (!display || display->Manager == SYS_HANDLE_INVALID)
        return NTLSTATUS_INVALID_PARAMETER;
    return SysClearDisplayManagerConsole(display->Manager, color);
}