/*
 * Copyright 1998-1999 Precision Insight, Inc., Cedar Park, Texas.
 * Copyright © 2008 Red Hat, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Soft-
 * ware"), to deal in the Software without restriction, including without
 * limitation the rights to use, copy, modify, merge, publish, distribute,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, provided that the above copyright
 * notice(s) and this permission notice appear in all copies of the Soft-
 * ware and that both the above copyright notice(s) and this permission
 * notice appear in supporting documentation.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABIL-
 * ITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY
 * RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN
 * THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSE-
 * QUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFOR-
 * MANCE OF THIS SOFTWARE.
 *
 * Except as contained in this notice, the name of a copyright holder shall
 * not be used in advertising or otherwise to promote the sale, use or
 * other dealings in this Software without prior written authorization of
 * the copyright holder.
 *
 * Authors:
 *   Kevin E. Martin <kevin@precisioninsight.com>
 *   Brian Paul <brian@precisioninsight.com>
 *   Kristian Høgsberg (krh@redhat.com)
 */

#ifdef GLX_DIRECT_RENDERING

#include <unistd.h>
#include <dlfcn.h>
#include <stdarg.h>
#include "glxclient.h"
#include "glcontextmodes.h"
#include "dri_common.h"

#ifndef RTLD_NOW
#define RTLD_NOW 0
#endif
#ifndef RTLD_GLOBAL
#define RTLD_GLOBAL 0
#endif

_X_HIDDEN void
InfoMessageF(const char *f, ...)
{
   va_list args;
   const char *env;

   if ((env = getenv("LIBGL_DEBUG")) && strstr(env, "verbose")) {
      fprintf(stderr, "libGL: ");
      va_start(args, f);
      vfprintf(stderr, f, args);
      va_end(args);
   }
}

/**
 * Print error to stderr, unless LIBGL_DEBUG=="quiet".
 */
_X_HIDDEN void
ErrorMessageF(const char *f, ...)
{
   va_list args;
   const char *env;

   if ((env = getenv("LIBGL_DEBUG")) && !strstr(env, "quiet")) {
      fprintf(stderr, "libGL error: ");
      va_start(args, f);
      vfprintf(stderr, f, args);
      va_end(args);
   }
}

#ifndef DEFAULT_DRIVER_DIR
/* this is normally defined in Mesa/configs/default with DRI_DRIVER_SEARCH_PATH */
#define DEFAULT_DRIVER_DIR "/usr/local/lib/dri"
#endif

/**
 * Try to \c dlopen the named driver.
 *
 * This function adds the "_dri.so" suffix to the driver name and searches the
 * directories specified by the \c LIBGL_DRIVERS_PATH environment variable in
 * order to find the driver.
 *
 * \param driverName - a name like "tdfx", "i810", "mga", etc.
 *
 * \returns
 * A handle from \c dlopen, or \c NULL if driver file not found.
 */
_X_HIDDEN void *
driOpenDriver(const char *driverName)
{
   void *glhandle, *handle;
   const char *libPaths, *p, *next;
   char realDriverName[200];
   int len;

   /* Attempt to make sure libGL symbols will be visible to the driver */
   glhandle = dlopen("libGL.so.1", RTLD_NOW | RTLD_GLOBAL);

   libPaths = NULL;
   if (geteuid() == getuid()) {
      /* don't allow setuid apps to use LIBGL_DRIVERS_PATH */
      libPaths = getenv("LIBGL_DRIVERS_PATH");
      if (!libPaths)
         libPaths = getenv("LIBGL_DRIVERS_DIR");        /* deprecated */
   }
   if (libPaths == NULL)
      libPaths = DEFAULT_DRIVER_DIR;

   handle = NULL;
   for (p = libPaths; *p; p = next) {
      next = strchr(p, ':');
      if (next == NULL) {
         len = strlen(p);
         next = p + len;
      }
      else {
         len = next - p;
         next++;
      }

#ifdef GLX_USE_TLS
      snprintf(realDriverName, sizeof realDriverName,
               "%.*s/tls/%s_dri.so", len, p, driverName);
      InfoMessageF("OpenDriver: trying %s\n", realDriverName);
      handle = dlopen(realDriverName, RTLD_NOW | RTLD_GLOBAL);
#endif

      if (handle == NULL) {
         snprintf(realDriverName, sizeof realDriverName,
                  "%.*s/%s_dri.so", len, p, driverName);
         InfoMessageF("OpenDriver: trying %s\n", realDriverName);
         handle = dlopen(realDriverName, RTLD_NOW | RTLD_GLOBAL);
      }

      if (handle != NULL)
         break;
      else
         ErrorMessageF("dlopen %s failed (%s)\n", realDriverName, dlerror());
   }

   if (!handle)
      ErrorMessageF("unable to load driver: %s_dri.so\n", driverName);

   if (glhandle)
      dlclose(glhandle);

   return handle;
}

_X_HIDDEN const __DRIsystemTimeExtension systemTimeExtension = {
   {__DRI_SYSTEM_TIME, __DRI_SYSTEM_TIME_VERSION},
   __glXGetUST,
   __driGetMscRateOML
};

#define __ATTRIB(attrib, field) \
    { attrib, offsetof(__GLcontextModes, field) }

static const struct
{
   unsigned int attrib, offset;
} attribMap[] = {
   __ATTRIB(__DRI_ATTRIB_BUFFER_SIZE, rgbBits),
      __ATTRIB(__DRI_ATTRIB_LEVEL, level),
      __ATTRIB(__DRI_ATTRIB_RED_SIZE, redBits),
      __ATTRIB(__DRI_ATTRIB_GREEN_SIZE, greenBits),
      __ATTRIB(__DRI_ATTRIB_BLUE_SIZE, blueBits),
      __ATTRIB(__DRI_ATTRIB_ALPHA_SIZE, alphaBits),
      __ATTRIB(__DRI_ATTRIB_DEPTH_SIZE, depthBits),
      __ATTRIB(__DRI_ATTRIB_STENCIL_SIZE, stencilBits),
      __ATTRIB(__DRI_ATTRIB_ACCUM_RED_SIZE, accumRedBits),
      __ATTRIB(__DRI_ATTRIB_ACCUM_GREEN_SIZE, accumGreenBits),
      __ATTRIB(__DRI_ATTRIB_ACCUM_BLUE_SIZE, accumBlueBits),
      __ATTRIB(__DRI_ATTRIB_ACCUM_ALPHA_SIZE, accumAlphaBits),
      __ATTRIB(__DRI_ATTRIB_SAMPLE_BUFFERS, sampleBuffers),
      __ATTRIB(__DRI_ATTRIB_SAMPLES, samples),
      __ATTRIB(__DRI_ATTRIB_DOUBLE_BUFFER, doubleBufferMode),
      __ATTRIB(__DRI_ATTRIB_STEREO, stereoMode),
      __ATTRIB(__DRI_ATTRIB_AUX_BUFFERS, numAuxBuffers),
#if 0
      __ATTRIB(__DRI_ATTRIB_TRANSPARENT_TYPE, transparentPixel),
      __ATTRIB(__DRI_ATTRIB_TRANSPARENT_INDEX_VALUE, transparentIndex),
      __ATTRIB(__DRI_ATTRIB_TRANSPARENT_RED_VALUE, transparentRed),
      __ATTRIB(__DRI_ATTRIB_TRANSPARENT_GREEN_VALUE, transparentGreen),
      __ATTRIB(__DRI_ATTRIB_TRANSPARENT_BLUE_VALUE, transparentBlue),
      __ATTRIB(__DRI_ATTRIB_TRANSPARENT_ALPHA_VALUE, transparentAlpha),
      __ATTRIB(__DRI_ATTRIB_RED_MASK, redMask),
      __ATTRIB(__DRI_ATTRIB_GREEN_MASK, greenMask),
      __ATTRIB(__DRI_ATTRIB_BLUE_MASK, blueMask),
      __ATTRIB(__DRI_ATTRIB_ALPHA_MASK, alphaMask),
#endif
      __ATTRIB(__DRI_ATTRIB_MAX_PBUFFER_WIDTH, maxPbufferWidth),
      __ATTRIB(__DRI_ATTRIB_MAX_PBUFFER_HEIGHT, maxPbufferHeight),
      __ATTRIB(__DRI_ATTRIB_MAX_PBUFFER_PIXELS, maxPbufferPixels),
      __ATTRIB(__DRI_ATTRIB_OPTIMAL_PBUFFER_WIDTH, optimalPbufferWidth),
      __ATTRIB(__DRI_ATTRIB_OPTIMAL_PBUFFER_HEIGHT, optimalPbufferHeight),
#if 0
      __ATTRIB(__DRI_ATTRIB_SWAP_METHOD, swapMethod),
#endif
__ATTRIB(__DRI_ATTRIB_BIND_TO_TEXTURE_RGB, bindToTextureRgb),
      __ATTRIB(__DRI_ATTRIB_BIND_TO_TEXTURE_RGBA, bindToTextureRgba),
      __ATTRIB(__DRI_ATTRIB_BIND_TO_MIPMAP_TEXTURE,
                     bindToMipmapTexture),
      __ATTRIB(__DRI_ATTRIB_YINVERTED, yInverted),};

#define ARRAY_SIZE(a) (sizeof (a) / sizeof ((a)[0]))

static int
scalarEqual(__GLcontextModes * mode, unsigned int attrib, unsigned int value)
{
   unsigned int glxValue;
   int i;

   for (i = 0; i < ARRAY_SIZE(attribMap); i++)
      if (attribMap[i].attrib == attrib) {
         glxValue = *(unsigned int *) ((char *) mode + attribMap[i].offset);
         return glxValue == GLX_DONT_CARE || glxValue == value;
      }

   return GL_TRUE;              /* Is a non-existing attribute equal to value? */
}

static int
driConfigEqual(const __DRIcoreExtension * core,
               __GLcontextModes * modes, const __DRIconfig * driConfig)
{
   unsigned int attrib, value, glxValue;
   int i;

   i = 0;
   while (core->indexConfigAttrib(driConfig, i++, &attrib, &value)) {
      switch (attrib) {
      case __DRI_ATTRIB_RENDER_TYPE:
         glxValue = 0;
         if (value & __DRI_ATTRIB_RGBA_BIT) {
            glxValue |= GLX_RGBA_BIT;
         }
         else if (value & __DRI_ATTRIB_COLOR_INDEX_BIT) {
            glxValue |= GLX_COLOR_INDEX_BIT;
         }
         if (glxValue != modes->renderType)
            return GL_FALSE;
         break;

      case __DRI_ATTRIB_CONFIG_CAVEAT:
         if (value & __DRI_ATTRIB_NON_CONFORMANT_CONFIG)
            glxValue = GLX_NON_CONFORMANT_CONFIG;
         else if (value & __DRI_ATTRIB_SLOW_BIT)
            glxValue = GLX_SLOW_CONFIG;
         else
            glxValue = GLX_NONE;
         if (glxValue != modes->visualRating)
            return GL_FALSE;
         break;

      case __DRI_ATTRIB_BIND_TO_TEXTURE_TARGETS:
         glxValue = 0;
         if (value & __DRI_ATTRIB_TEXTURE_1D_BIT)
            glxValue |= GLX_TEXTURE_1D_BIT_EXT;
         if (value & __DRI_ATTRIB_TEXTURE_2D_BIT)
            glxValue |= GLX_TEXTURE_2D_BIT_EXT;
         if (value & __DRI_ATTRIB_TEXTURE_RECTANGLE_BIT)
            glxValue |= GLX_TEXTURE_RECTANGLE_BIT_EXT;
         if (modes->bindToTextureTargets != GLX_DONT_CARE &&
             glxValue != modes->bindToTextureTargets)
            return GL_FALSE;
         break;

      default:
         if (!scalarEqual(modes, attrib, value))
            return GL_FALSE;
      }
   }

   return GL_TRUE;
}

static __GLcontextModes *
createDriMode(const __DRIcoreExtension * core,
              __GLcontextModes * modes, const __DRIconfig ** driConfigs)
{
   __GLXDRIconfigPrivate *config;
   int i;

   for (i = 0; driConfigs[i]; i++) {
      if (driConfigEqual(core, modes, driConfigs[i]))
         break;
   }

   if (driConfigs[i] == NULL)
      return NULL;

   config = Xmalloc(sizeof *config);
   if (config == NULL)
      return NULL;

   config->modes = *modes;
   config->driConfig = driConfigs[i];

   return &config->modes;
}

_X_HIDDEN __GLcontextModes *
driConvertConfigs(const __DRIcoreExtension * core,
                  __GLcontextModes * modes, const __DRIconfig ** configs)
{
   __GLcontextModes head, *tail, *m;

   tail = &head;
   head.next = NULL;
   for (m = modes; m; m = m->next) {
      tail->next = createDriMode(core, m, configs);
      if (tail->next == NULL) {
         /* no matching dri config for m */
         continue;
      }


      tail = tail->next;
   }

   _gl_context_modes_destroy(modes);

   return head.next;
}

/* Bind DRI1 specific extensions */
_X_HIDDEN void
driBindExtensions(__GLXscreenConfigs *psc)
{
   const __DRIextension **extensions;
   int i;

   extensions = psc->core->getExtensions(psc->__driScreen);

   for (i = 0; extensions[i]; i++) {
#ifdef __DRI_SWAP_CONTROL
      /* No DRI2 support for swap_control at the moment, since SwapBuffers
       * is done by the X server */
      if (strcmp(extensions[i]->name, __DRI_SWAP_CONTROL) == 0) {
	 psc->swapControl = (__DRIswapControlExtension *) extensions[i];
	 __glXEnableDirectExtension(psc, "GLX_SGI_swap_control");
	 __glXEnableDirectExtension(psc, "GLX_MESA_swap_control");
      }
#endif

#ifdef __DRI_MEDIA_STREAM_COUNTER
      if (strcmp(extensions[i]->name, __DRI_MEDIA_STREAM_COUNTER) == 0) {
         psc->msc = (__DRImediaStreamCounterExtension *) extensions[i];
         __glXEnableDirectExtension(psc, "GLX_SGI_video_sync");
      }
#endif

#ifdef __DRI_SWAP_BUFFER_COUNTER
      /* No driver supports this at this time and the extension is
       * not defined in dri_interface.h.  Will enable
       * GLX_OML_sync_control if implemented. */
#endif

      /* Ignore unknown extensions */
   }
}

/* Bind DRI2 specific extensions */
_X_HIDDEN void
dri2BindExtensions(__GLXscreenConfigs *psc)
{
   const __DRIextension **extensions;
   int i;

   extensions = psc->core->getExtensions(psc->__driScreen);

   for (i = 0; extensions[i]; i++) {
#ifdef __DRI_TEX_BUFFER
      if ((strcmp(extensions[i]->name, __DRI_TEX_BUFFER) == 0)) {
	 psc->texBuffer = (__DRItexBufferExtension *) extensions[i];
	 __glXEnableDirectExtension(psc, "GLX_EXT_texture_from_pixmap");
      }
#endif

      __glXEnableDirectExtension(psc, "GLX_SGI_video_sync");
      __glXEnableDirectExtension(psc, "GLX_SGI_swap_control");
      __glXEnableDirectExtension(psc, "GLX_MESA_swap_control");

      /* FIXME: if DRI2 version supports it... */
      __glXEnableDirectExtension(psc, "INTEL_swap_event");

#ifdef __DRI2_FLUSH
      if ((strcmp(extensions[i]->name, __DRI2_FLUSH) == 0)) {
	 psc->f = (__DRI2flushExtension *) extensions[i];
	 /* internal driver extension, no GL extension exposed */
      }
#endif
   }
}

/* Bind extensions common to DRI1 and DRI2 */
_X_HIDDEN void
driBindCommonExtensions(__GLXscreenConfigs *psc)
{
   const __DRIextension **extensions;
   int i;

   extensions = psc->core->getExtensions(psc->__driScreen);

   for (i = 0; extensions[i]; i++) {
#ifdef __DRI_COPY_SUB_BUFFER
      if (strcmp(extensions[i]->name, __DRI_COPY_SUB_BUFFER) == 0) {
	 psc->driCopySubBuffer = (__DRIcopySubBufferExtension *) extensions[i];
	 __glXEnableDirectExtension(psc, "GLX_MESA_copy_sub_buffer");
      }
#endif

#ifdef __DRI_ALLOCATE
      if (strcmp(extensions[i]->name, __DRI_ALLOCATE) == 0) {
	 psc->allocate = (__DRIallocateExtension *) extensions[i];
	 __glXEnableDirectExtension(psc, "GLX_MESA_allocate_memory");
      }
#endif

#ifdef __DRI_FRAME_TRACKING
      if (strcmp(extensions[i]->name, __DRI_FRAME_TRACKING) == 0) {
	 psc->frameTracking = (__DRIframeTrackingExtension *) extensions[i];
	 __glXEnableDirectExtension(psc, "GLX_MESA_swap_frame_usage");
      }
#endif

#ifdef __DRI_READ_DRAWABLE
      if (strcmp(extensions[i]->name, __DRI_READ_DRAWABLE) == 0) {
	 __glXEnableDirectExtension(psc, "GLX_SGI_make_current_read");
      }
#endif

      /* Ignore unknown extensions */
   }
}

#endif /* GLX_DIRECT_RENDERING */