/*
 * Copyright © 2016 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

#include <stdbool.h>
#include "context.h"
#include "debug_output.h"
#include "get.h"
#include "mtypes.h"
#include "macros.h"
#include "main/dispatch.h" /* for _gloffset_COUNT */

static void GLAPIENTRY
_context_lost_GetSynciv(GLsync sync, GLenum pname, GLsizei bufSize,
                        GLsizei *length, GLint *values)
{
   GET_CURRENT_CONTEXT(ctx);
   if (ctx)
      _mesa_error(ctx, GL_CONTEXT_LOST, "GetSynciv(invalid call)");

   if (pname == GL_SYNC_STATUS && bufSize >= 1)
      *values = GL_SIGNALED;
}

static void GLAPIENTRY
_context_lost_GetQueryObjectuiv(GLuint id, GLenum pname, GLuint *params)
{
   GET_CURRENT_CONTEXT(ctx);
   if (ctx)
      _mesa_error(ctx, GL_CONTEXT_LOST, "GetQueryObjectuiv(context lost)");

   if (pname == GL_QUERY_RESULT_AVAILABLE)
      *params = GL_TRUE;
}

static int
context_lost_nop_handler(void)
{
   GET_CURRENT_CONTEXT(ctx);
   if (ctx)
      _mesa_error(ctx, GL_CONTEXT_LOST, "context lost");

   return 0;
}

void
_mesa_set_context_lost_dispatch(struct gl_context *ctx)
{
   if (ctx->ContextLost == NULL) {
      int numEntries = MAX2(_glapi_get_dispatch_table_size(), _gloffset_COUNT);

      ctx->ContextLost = malloc(numEntries * sizeof(_glapi_proc));
      if (!ctx->ContextLost)
         return;

      _glapi_proc *entry = (_glapi_proc *) ctx->ContextLost;
      unsigned i;
      for (i = 0; i < numEntries; i++)
         entry[i] = (_glapi_proc) context_lost_nop_handler;

      /* The ARB_robustness specification says:
       *
       *    "* GetError and GetGraphicsResetStatus behave normally following a
       *       graphics reset, so that the application can determine a reset
       *       has occurred, and when it is safe to destroy and recreate the
       *       context.
       *
       *     * Any commands which might cause a polling application to block
       *       indefinitely will generate a CONTEXT_LOST error, but will also
       *       return a value indicating completion to the application. Such
       *       commands include:
       *
       *        + GetSynciv with <pname> SYNC_STATUS ignores the other
       *          parameters and returns SIGNALED in <values>.
       *
       *        + GetQueryObjectuiv with <pname> QUERY_RESULT_AVAILABLE
       *          ignores the other parameters and returns TRUE in <params>."
       */
      SET_GetError(ctx->ContextLost, _mesa_GetError);
      SET_GetGraphicsResetStatusARB(ctx->ContextLost, _mesa_GetGraphicsResetStatusARB);
      SET_GetSynciv(ctx->ContextLost, _context_lost_GetSynciv);
      SET_GetQueryObjectuiv(ctx->ContextLost, _context_lost_GetQueryObjectuiv);
   }

   ctx->CurrentDispatch = ctx->ContextLost;
   _glapi_set_dispatch(ctx->CurrentDispatch);
}

/**
 * Returns an error code specified by GL_ARB_robustness, or GL_NO_ERROR.
 * \return current context status
 */
GLenum GLAPIENTRY
_mesa_GetGraphicsResetStatusARB( void )
{
   GET_CURRENT_CONTEXT(ctx);
   GLenum status = GL_NO_ERROR;

   /* The ARB_robustness specification says:
    *
    *     "If the reset notification behavior is NO_RESET_NOTIFICATION_ARB,
    *     then the implementation will never deliver notification of reset
    *     events, and GetGraphicsResetStatusARB will always return NO_ERROR."
    */
   if (ctx->Const.ResetStrategy == GL_NO_RESET_NOTIFICATION_ARB) {
      if (MESA_VERBOSE & VERBOSE_API)
         _mesa_debug(ctx,
                     "glGetGraphicsResetStatusARB always returns GL_NO_ERROR "
                     "because reset notifictation was not requested at context "
                     "creation.\n");

      return GL_NO_ERROR;
   }

   if (ctx->Driver.GetGraphicsResetStatus) {
      /* Query the reset status of this context from the driver core.
       */
      status = ctx->Driver.GetGraphicsResetStatus(ctx);

      mtx_lock(&ctx->Shared->Mutex);

      /* If this context has not been affected by a GPU reset, check to see if
       * some other context in the share group has been affected by a reset.
       * If another context saw a reset but this context did not, assume that
       * this context was not guilty.
       */
      if (status != GL_NO_ERROR) {
         ctx->Shared->ShareGroupReset = true;
      } else if (ctx->Shared->ShareGroupReset && !ctx->ShareGroupReset) {
         status = GL_INNOCENT_CONTEXT_RESET_ARB;
      }

      ctx->ShareGroupReset = ctx->Shared->ShareGroupReset;
      mtx_unlock(&ctx->Shared->Mutex);
   }

   if (status != GL_NO_ERROR)
      _mesa_set_context_lost_dispatch(ctx);

   if (!ctx->Driver.GetGraphicsResetStatus && (MESA_VERBOSE & VERBOSE_API))
      _mesa_debug(ctx,
                  "glGetGraphicsResetStatusARB always returns GL_NO_ERROR "
                  "because the driver doesn't track reset status.\n");

   return status;
}