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 /*

  * Copyright © 2000 SuSE, Inc.

  * Copyright © 1999 Keith Packard

  *

  * Permission to use, copy, modify, distribute, and sell this software and its

  * documentation for any purpose is hereby granted without fee, provided that

  * the above copyright notice appear in all copies and that both that

  * copyright notice and this permission notice appear in supporting

  * documentation, and that the name of SuSE not be used in advertising or

  * publicity pertaining to distribution of the software without specific,

  * written prior permission.  SuSE makes no representations about the

  * suitability of this software for any purpose.  It is provided "as is"

  * without express or implied warranty.

  *

  * SuSE DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL

  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL SuSE

  * BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL 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 PERFORMANCE OF THIS SOFTWARE.

  *

  * Author:  Keith Packard, SuSE, Inc.

  */

 #ifdef HAVE_CONFIG_H

 #include <config.h>

 #endif

 #include <stdio.h>

 #include <stdlib.h>

 #include <limits.h>

 #include "pixman-private.h"

 pixman_bool_t

 _pixman_multiply_overflows_size (size_t a, size_t b)

 {

     return a >= SIZE_MAX / b;

 }

 pixman_bool_t

 _pixman_multiply_overflows_int (unsigned int a, unsigned int b)

 {

     return a >= INT32_MAX / b;

 }

 pixman_bool_t

 _pixman_addition_overflows_int (unsigned int a, unsigned int b)

 {

     return a > INT32_MAX - b;

 }

 void *

 pixman_malloc_ab (unsigned int a,

                   unsigned int b)

 {

     if (a >= INT32_MAX / b)

 	return NULL;

     return malloc (a * b);

 }

 void *

 pixman_malloc_abc (unsigned int a,

                    unsigned int b,

                    unsigned int c)

 {

     if (a >= INT32_MAX / b)

 	return NULL;

     else if (a * b >= INT32_MAX / c)

 	return NULL;

     else

 	return malloc (a * b * c);

 }

 static force_inline uint16_t

 float_to_unorm (float f, int n_bits)

 {

     uint32_t u;

     if (f > 1.0)

 	f = 1.0;

     if (f < 0.0)

 	f = 0.0;

     u = f * (1 << n_bits);

     u -= (u >> n_bits);

     return u;

 }

 static force_inline float

 unorm_to_float (uint16_t u, int n_bits)

 {

     uint32_t m = ((1 << n_bits) - 1);

     return (u & m) * (1.f / (float)m);

 }

 /*

  * This function expands images from a8r8g8b8 to argb_t.  To preserve

  * precision, it needs to know from which source format the a8r8g8b8 pixels

  * originally came.

  *

  * For example, if the source was PIXMAN_x1r5g5b5 and the red component

  * contained bits 12345, then the 8-bit value is 12345123.  To correctly

  * expand this to floating point, it should be 12345 / 31.0 and not

  * 12345123 / 255.0.

  */

 void

 pixman_expand_to_float (argb_t               *dst,

 			const uint32_t       *src,

 			pixman_format_code_t  format,

 			int                   width)

 {

     static const float multipliers[16] = {

 	0.0f,

 	1.0f / ((1 <<  1) - 1),

 	1.0f / ((1 <<  2) - 1),

 	1.0f / ((1 <<  3) - 1),

 	1.0f / ((1 <<  4) - 1),

 	1.0f / ((1 <<  5) - 1),

 	1.0f / ((1 <<  6) - 1),

 	1.0f / ((1 <<  7) - 1),

 	1.0f / ((1 <<  8) - 1),

 	1.0f / ((1 <<  9) - 1),

 	1.0f / ((1 << 10) - 1),

 	1.0f / ((1 << 11) - 1),

 	1.0f / ((1 << 12) - 1),

 	1.0f / ((1 << 13) - 1),

 	1.0f / ((1 << 14) - 1),

 	1.0f / ((1 << 15) - 1),

     };

     int a_size, r_size, g_size, b_size;

     int a_shift, r_shift, g_shift, b_shift;

     float a_mul, r_mul, g_mul, b_mul;

     uint32_t a_mask, r_mask, g_mask, b_mask;

     int i;

     if (!PIXMAN_FORMAT_VIS (format))

 	format = PIXMAN_a8r8g8b8;

     /*

      * Determine the sizes of each component and the masks and shifts

      * required to extract them from the source pixel.

      */

     a_size = PIXMAN_FORMAT_A (format);

     r_size = PIXMAN_FORMAT_R (format);

     g_size = PIXMAN_FORMAT_G (format);

     b_size = PIXMAN_FORMAT_B (format);

     a_shift = 32 - a_size;

     r_shift = 24 - r_size;

     g_shift = 16 - g_size;

     b_shift =  8 - b_size;

     a_mask = ((1 << a_size) - 1);

     r_mask = ((1 << r_size) - 1);

     g_mask = ((1 << g_size) - 1);

     b_mask = ((1 << b_size) - 1);

     a_mul = multipliers[a_size];

     r_mul = multipliers[r_size];

     g_mul = multipliers[g_size];

     b_mul = multipliers[b_size];

     /* Start at the end so that we can do the expansion in place

      * when src == dst

      */

     for (i = width - 1; i >= 0; i--)

     {

 	const uint32_t pixel = src[i];

 	dst[i].a = a_mask? ((pixel >> a_shift) & a_mask) * a_mul : 1.0f;

 	dst[i].r = ((pixel >> r_shift) & r_mask) * r_mul;

 	dst[i].g = ((pixel >> g_shift) & g_mask) * g_mul;

 	dst[i].b = ((pixel >> b_shift) & b_mask) * b_mul;

     }

 }

 uint16_t

 pixman_float_to_unorm (float f, int n_bits)

 {

     return float_to_unorm (f, n_bits);

 }

 float

 pixman_unorm_to_float (uint16_t u, int n_bits)

 {

     return unorm_to_float (u, n_bits);

 }

 void

 pixman_contract_from_float (uint32_t     *dst,

 			    const argb_t *src,

 			    int           width)

 {

     int i;

     for (i = 0; i < width; ++i)

     {

 	uint8_t a, r, g, b;

 	a = float_to_unorm (src[i].a, 8);

 	r = float_to_unorm (src[i].r, 8);

 	g = float_to_unorm (src[i].g, 8);

 	b = float_to_unorm (src[i].b, 8);

 	dst[i] = (a << 24) | (r << 16) | (g << 8) | (b << 0);

     }

 }

 uint32_t *

 _pixman_iter_get_scanline_noop (pixman_iter_t *iter, const uint32_t *mask)

 {

     return iter->buffer;

 }

 #define N_TMP_BOXES (16)

 pixman_bool_t

 pixman_region16_copy_from_region32 (pixman_region16_t *dst,

                                     pixman_region32_t *src)

 {

     int n_boxes, i;

     pixman_box32_t *boxes32;

     pixman_box16_t *boxes16;

     pixman_bool_t retval;

     boxes32 = pixman_region32_rectangles (src, &n_boxes);

     boxes16 = pixman_malloc_ab (n_boxes, sizeof (pixman_box16_t));

     if (!boxes16)

 	return FALSE;

     for (i = 0; i < n_boxes; ++i)

     {

 	boxes16[i].x1 = boxes32[i].x1;

 	boxes16[i].y1 = boxes32[i].y1;

 	boxes16[i].x2 = boxes32[i].x2;

 	boxes16[i].y2 = boxes32[i].y2;

     }

     pixman_region_fini (dst);

     retval = pixman_region_init_rects (dst, boxes16, n_boxes);

     free (boxes16);

     return retval;

 }

 pixman_bool_t

 pixman_region32_copy_from_region16 (pixman_region32_t *dst,

                                     pixman_region16_t *src)

 {

     int n_boxes, i;

     pixman_box16_t *boxes16;

     pixman_box32_t *boxes32;

     pixman_box32_t tmp_boxes[N_TMP_BOXES];

     pixman_bool_t retval;

     boxes16 = pixman_region_rectangles (src, &n_boxes);

     if (n_boxes > N_TMP_BOXES)

 	boxes32 = pixman_malloc_ab (n_boxes, sizeof (pixman_box32_t));

     else

 	boxes32 = tmp_boxes;

     if (!boxes32)

 	return FALSE;

     for (i = 0; i < n_boxes; ++i)

     {

 	boxes32[i].x1 = boxes16[i].x1;

 	boxes32[i].y1 = boxes16[i].y1;

 	boxes32[i].x2 = boxes16[i].x2;

 	boxes32[i].y2 = boxes16[i].y2;

     }

     pixman_region32_fini (dst);

     retval = pixman_region32_init_rects (dst, boxes32, n_boxes);

     if (boxes32 != tmp_boxes)

 	free (boxes32);

     return retval;

 }

 /* This function is exported for the sake of the test suite and not part

  * of the ABI.

  */

 PIXMAN_EXPORT pixman_implementation_t *

 _pixman_internal_only_get_implementation (void)

 {

     return get_implementation ();

 }

 #ifdef DEBUG

 void

 _pixman_log_error (const char *function, const char *message)

 {

     static int n_messages = 0;

     if (n_messages < 10)

     {

 	fprintf (stderr,

 		 "*** BUG ***\n"

 		 "In %s: %s\n"

 		 "Set a breakpoint on '_pixman_log_error' to debug\n\n",

                  function, message);

 	n_messages++;

     }

 }

 #endif