#define _GNU_SOURCE

#include "utils.h"

#include <math.h>

#include <signal.h>

#include <stdlib.h>

#include <float.h>

#include <ctype.h>

#include <limits.h>

#ifdef HAVE_GETTIMEOFDAY

#include <sys/time.h>

#else

#include <time.h>

#endif

#ifdef HAVE_UNISTD_H

#include <unistd.h>

#endif

#ifdef HAVE_SYS_MMAN_H

#include <sys/mman.h>

#endif

#ifdef HAVE_FENV_H

#include <fenv.h>

#endif

#ifdef HAVE_LIBPNG

#include <png.h>

#endif

#define ROUND_UP(x, mult) (((x) + (mult) - 1) / (mult) * (mult))

/* Random number generator state

 */

prng_t prng_state_data;

prng_t *prng_state;

/*----------------------------------------------------------------------------*\

 *  CRC-32 version 2.0.0 by Craig Bruce, 2006-04-29.

 *

 *  This program generates the CRC-32 values for the files named in the

 *  command-line arguments.  These are the same CRC-32 values used by GZIP,

 *  PKZIP, and ZMODEM.  The Crc32_ComputeBuf () can also be detached and

 *  used independently.

 *

 *  THIS PROGRAM IS PUBLIC-DOMAIN SOFTWARE.

 *

 *  Based on the byte-oriented implementation "File Verification Using CRC"

 *  by Mark R. Nelson in Dr. Dobb's Journal, May 1992, pp. 64-67.

 *

 *  v1.0.0: original release.

 *  v1.0.1: fixed printf formats.

 *  v1.0.2: fixed something else.

 *  v1.0.3: replaced CRC constant table by generator function.

 *  v1.0.4: reformatted code, made ANSI C.  1994-12-05.

 *  v2.0.0: rewrote to use memory buffer & static table, 2006-04-29.

\*----------------------------------------------------------------------------*/

/*----------------------------------------------------------------------------*\

 *  NAME:

 *     Crc32_ComputeBuf () - computes the CRC-32 value of a memory buffer

 *  DESCRIPTION:

 *     Computes or accumulates the CRC-32 value for a memory buffer.

 *     The 'inCrc32' gives a previously accumulated CRC-32 value to allow

 *     a CRC to be generated for multiple sequential buffer-fuls of data.

 *     The 'inCrc32' for the first buffer must be zero.

 *  ARGUMENTS:

 *     inCrc32 - accumulated CRC-32 value, must be 0 on first call

 *     buf     - buffer to compute CRC-32 value for

 *     bufLen  - number of bytes in buffer

 *  RETURNS:

 *     crc32 - computed CRC-32 value

 *  ERRORS:

 *     (no errors are possible)

\*----------------------------------------------------------------------------*/

uint32_t

compute_crc32 (uint32_t    in_crc32,

	       const void *buf,

	       size_t      buf_len)

{

    static const uint32_t crc_table[256] = {

	0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F,

	0xE963A535, 0x9E6495A3, 0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988,

	0x09B64C2B, 0x7EB17CBD,	0xE7B82D07, 0x90BF1D91, 0x1DB71064, 0x6AB020F2,

	0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,

	0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC,	0x14015C4F, 0x63066CD9,

	0xFA0F3D63, 0x8D080DF5, 0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172,

	0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B, 0x35B5A8FA, 0x42B2986C,

	0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,

	0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423,

	0xCFBA9599, 0xB8BDA50F, 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924,

	0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D, 0x76DC4190, 0x01DB7106,

	0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,

	0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D,

	0x91646C97, 0xE6635C01, 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E,

	0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457, 0x65B0D9C6, 0x12B7E950,

	0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,

	0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7,

	0xA4D1C46D, 0xD3D6F4FB, 0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0,

	0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9, 0x5005713C, 0x270241AA,

	0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,

	0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81,

	0xB7BD5C3B, 0xC0BA6CAD, 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A,

	0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683, 0xE3630B12, 0x94643B84,

	0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,

	0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB,

	0x196C3671, 0x6E6B06E7, 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC,

	0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5, 0xD6D6A3E8, 0xA1D1937E,

	0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,

	0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55,

	0x316E8EEF, 0x4669BE79, 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236,

	0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F, 0xC5BA3BBE, 0xB2BD0B28,

	0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,

	0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F,

	0x72076785, 0x05005713, 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38,

	0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21, 0x86D3D2D4, 0xF1D4E242,

	0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,

	0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69,

	0x616BFFD3, 0x166CCF45, 0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2,

	0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB, 0xAED16A4A, 0xD9D65ADC,

	0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,

	0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693,

	0x54DE5729, 0x23D967BF, 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94,

	0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D

    };

    uint32_t              crc32;

    unsigned char *       byte_buf;

    size_t                i;

    /* accumulate crc32 for buffer */

    crc32 = in_crc32 ^ 0xFFFFFFFF;

    byte_buf = (unsigned char*) buf;

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

	crc32 = (crc32 >> 8) ^ crc_table[(crc32 ^ byte_buf[i]) & 0xFF];

    return (crc32 ^ 0xFFFFFFFF);

}

static uint32_t

compute_crc32_for_image_internal (uint32_t        crc32,

				  pixman_image_t *img,

				  pixman_bool_t	  remove_alpha,

				  pixman_bool_t	  remove_rgb)

{

    pixman_format_code_t fmt = pixman_image_get_format (img);

    uint32_t *data = pixman_image_get_data (img);

    int stride = pixman_image_get_stride (img);

    int height = pixman_image_get_height (img);

    uint32_t mask = 0xffffffff;

    int i;

    if (stride < 0)

    {

	data += (stride / 4) * (height - 1);

	stride = - stride;

    }

    /* mask unused 'x' part */

    if (PIXMAN_FORMAT_BPP (fmt) - PIXMAN_FORMAT_DEPTH (fmt) &&

	PIXMAN_FORMAT_DEPTH (fmt) != 0)

    {

	uint32_t m = (1 << PIXMAN_FORMAT_DEPTH (fmt)) - 1;

	if (PIXMAN_FORMAT_TYPE (fmt) == PIXMAN_TYPE_BGRA ||

	    PIXMAN_FORMAT_TYPE (fmt) == PIXMAN_TYPE_RGBA)

	{

	    m <<= (PIXMAN_FORMAT_BPP (fmt) - PIXMAN_FORMAT_DEPTH (fmt));

	}

	mask &= m;

    }

    /* mask alpha channel */

    if (remove_alpha && PIXMAN_FORMAT_A (fmt))

    {

	uint32_t m;

	if (PIXMAN_FORMAT_BPP (fmt) == 32)

	    m = 0xffffffff;

	else

	    m = (1 << PIXMAN_FORMAT_BPP (fmt)) - 1;

	m >>= PIXMAN_FORMAT_A (fmt);

	if (PIXMAN_FORMAT_TYPE (fmt) == PIXMAN_TYPE_BGRA ||

	    PIXMAN_FORMAT_TYPE (fmt) == PIXMAN_TYPE_RGBA ||

	    PIXMAN_FORMAT_TYPE (fmt) == PIXMAN_TYPE_A)

	{

	    /* Alpha is at the bottom of the pixel */

	    m <<= PIXMAN_FORMAT_A (fmt);

	}

	mask &= m;

    }

    /* mask rgb channels */

    if (remove_rgb && PIXMAN_FORMAT_RGB (fmt))

    {

	uint32_t m = ((uint32_t)~0) >> (32 - PIXMAN_FORMAT_BPP (fmt));

	uint32_t size = PIXMAN_FORMAT_R (fmt) + PIXMAN_FORMAT_G (fmt) + PIXMAN_FORMAT_B (fmt);

	m &= ~((1 << size) - 1);

	if (PIXMAN_FORMAT_TYPE (fmt) == PIXMAN_TYPE_BGRA ||

	    PIXMAN_FORMAT_TYPE (fmt) == PIXMAN_TYPE_RGBA)

	{

	    /* RGB channels are at the top of the pixel */

	    m >>= size;

	}

	mask &= m;

    }

    for (i = 0; i * PIXMAN_FORMAT_BPP (fmt) < 32; i++)

	mask |= mask << (i * PIXMAN_FORMAT_BPP (fmt));

    for (i = 0; i < stride * height / 4; i++)

	data[i] &= mask;

    /* swap endiannes in order to provide identical results on both big

     * and litte endian systems

     */

    image_endian_swap (img);

    return compute_crc32 (crc32, data, stride * height);

}

uint32_t

compute_crc32_for_image (uint32_t        crc32,

			 pixman_image_t *img)

{

    if (img->common.alpha_map)

    {

	crc32 = compute_crc32_for_image_internal (crc32, img, TRUE, FALSE);

	crc32 = compute_crc32_for_image_internal (

	    crc32, (pixman_image_t *)img->common.alpha_map, FALSE, TRUE);

    }

    else

    {

	crc32 = compute_crc32_for_image_internal (crc32, img, FALSE, FALSE);

    }

    return crc32;

}

void

print_image (pixman_image_t *image)

{

    int i, j;

    int width, height, stride;

    pixman_format_code_t format;

    uint8_t *buffer;

    int s;

    width = pixman_image_get_width (image);

    height = pixman_image_get_height (image);

    stride = pixman_image_get_stride (image);

    format = pixman_image_get_format (image);

    buffer = (uint8_t *)pixman_image_get_data (image);

    s = (stride >= 0)? stride : - stride;

    printf ("---\n");

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

    {

	for (j = 0; j < s; j++)

	{

	    if (j == (width * PIXMAN_FORMAT_BPP (format) + 7) / 8)

		printf ("| ");

	    printf ("%02X ", *((uint8_t *)buffer + i * stride + j));

	}

	printf ("\n");

    }

    printf ("---\n");

}

/* perform endian conversion of pixel data

 */

void

image_endian_swap (pixman_image_t *img)

{

    int stride = pixman_image_get_stride (img);

    uint32_t *data = pixman_image_get_data (img);

    int height = pixman_image_get_height (img);

    int bpp = PIXMAN_FORMAT_BPP (pixman_image_get_format (img));

    int i, j;

    /* swap bytes only on big endian systems */

    if (is_little_endian())

	return;

    if (bpp == 8)

	return;

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

    {

	uint8_t *line_data = (uint8_t *)data + stride * i;

	int s = (stride >= 0)? stride : - stride;

	switch (bpp)

	{

	case 1:

	    for (j = 0; j < s; j++)

	    {

		line_data[j] =

		    ((line_data[j] & 0x80) >> 7) |

		    ((line_data[j] & 0x40) >> 5) |

		    ((line_data[j] & 0x20) >> 3) |

		    ((line_data[j] & 0x10) >> 1) |

		    ((line_data[j] & 0x08) << 1) |

		    ((line_data[j] & 0x04) << 3) |

		    ((line_data[j] & 0x02) << 5) |

		    ((line_data[j] & 0x01) << 7);

	    }

	    break;

	case 4:

	    for (j = 0; j < s; j++)

	    {

		line_data[j] = (line_data[j] >> 4) | (line_data[j] << 4);

	    }

	    break;

	case 16:

	    for (j = 0; j + 2 <= s; j += 2)

	    {

		char t1 = line_data[j + 0];

		char t2 = line_data[j + 1];

		line_data[j + 1] = t1;

		line_data[j + 0] = t2;

	    }

	    break;

	case 24:

	    for (j = 0; j + 3 <= s; j += 3)

	    {

		char t1 = line_data[j + 0];

		char t2 = line_data[j + 1];

		char t3 = line_data[j + 2];

		line_data[j + 2] = t1;

		line_data[j + 1] = t2;

		line_data[j + 0] = t3;

	    }

	    break;

	case 32:

	    for (j = 0; j + 4 <= s; j += 4)

	    {

		char t1 = line_data[j + 0];

		char t2 = line_data[j + 1];

		char t3 = line_data[j + 2];

		char t4 = line_data[j + 3];

		line_data[j + 3] = t1;

		line_data[j + 2] = t2;

		line_data[j + 1] = t3;

		line_data[j + 0] = t4;

	    }

	    break;

	default:

	    assert (FALSE);

	    break;

	}

    }

}

#define N_LEADING_PROTECTED	10

#define N_TRAILING_PROTECTED	10

typedef struct

{

    void *addr;

    uint32_t len;

    uint8_t *trailing;

    int n_bytes;

} info_t;

#if FENCE_MALLOC_ACTIVE

unsigned long

fence_get_page_size ()

{

    /* You can fake a page size here, if you want to test e.g. 64 kB

     * pages on a 4 kB page system. Just put a multiplier below.

     */

    return getpagesize ();

}

/* This is apparently necessary on at least OS X */

#ifndef MAP_ANONYMOUS

#define MAP_ANONYMOUS MAP_ANON

#endif

void *

fence_malloc (int64_t len)

{

    unsigned long page_size = fence_get_page_size ();

    unsigned long page_mask = page_size - 1;

    uint32_t n_payload_bytes = (len + page_mask) & ~page_mask;

    uint32_t n_bytes =

	(page_size * (N_LEADING_PROTECTED + N_TRAILING_PROTECTED + 2) +

	 n_payload_bytes) & ~page_mask;

    uint8_t *initial_page;

    uint8_t *leading_protected;

    uint8_t *trailing_protected;

    uint8_t *payload;

    uint8_t *addr;

    if (len < 0)

	abort();

    addr = mmap (NULL, n_bytes, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS,

		 -1, 0);

    if (addr == MAP_FAILED)

    {

	printf ("mmap failed on %lld %u\n", (long long int)len, n_bytes);

	return NULL;

    }

    initial_page = (uint8_t *)(((uintptr_t)addr + page_mask) & ~page_mask);

    leading_protected = initial_page + page_size;

    payload = leading_protected + N_LEADING_PROTECTED * page_size;

    trailing_protected = payload + n_payload_bytes;

    ((info_t *)initial_page)->addr = addr;

    ((info_t *)initial_page)->len = len;

    ((info_t *)initial_page)->trailing = trailing_protected;

    ((info_t *)initial_page)->n_bytes = n_bytes;

    if ((mprotect (leading_protected, N_LEADING_PROTECTED * page_size,

		  PROT_NONE) == -1) ||

	(mprotect (trailing_protected, N_TRAILING_PROTECTED * page_size,

		  PROT_NONE) == -1))

    {

	munmap (addr, n_bytes);

	return NULL;

    }

    return payload;

}

void

fence_free (void *data)

{

    uint32_t page_size = fence_get_page_size ();

    uint8_t *payload = data;

    uint8_t *leading_protected = payload - N_LEADING_PROTECTED * page_size;

    uint8_t *initial_page = leading_protected - page_size;

    info_t *info = (info_t *)initial_page;

    munmap (info->addr, info->n_bytes);

}

static void

fence_image_destroy (pixman_image_t *image, void *data)

{

    fence_free (data);

}

/* Create an image with fence pages.

 *

 * Creates an image, where the data area is allocated with fence_malloc ().

 * Each row has an additional page in the stride.

 *

 * min_width is only a minimum width for the image. The width is aligned up

 * for the row size to be divisible by both page size and pixel size.

 *

 * If stride_fence is true, the additional page on each row will be

 * armed to cause SIGSEGV or SIGBUS on all accesses. This should catch

 * all accesses outside the valid row pixels.

 */

pixman_image_t *

fence_image_create_bits (pixman_format_code_t format,

                         int min_width,

                         int height,

                         pixman_bool_t stride_fence)

{

    unsigned page_size = fence_get_page_size ();

    unsigned page_mask = page_size - 1;

    unsigned bitspp = PIXMAN_FORMAT_BPP (format);

    unsigned bits_boundary;

    unsigned row_bits;

    int width;       /* pixels */

    unsigned stride; /* bytes */

    void *pixels;

    pixman_image_t *image;

    int i;

    /* must be power of two */

    assert (page_size && (page_size & page_mask) == 0);

    if (bitspp < 1 || min_width < 1 || height < 1)

        abort ();

    /* least common multiple between page size * 8 and bitspp */

    bits_boundary = bitspp;

    while (! (bits_boundary & 1))

        bits_boundary >>= 1;

    bits_boundary *= page_size * 8;

    /* round up to bits_boundary */

    row_bits = ROUND_UP ( (unsigned)min_width * bitspp, bits_boundary);

    width = row_bits / bitspp;

    stride = row_bits / 8;

    if (stride_fence)

        stride += page_size; /* add fence page */

    if (UINT_MAX / stride < (unsigned)height)

        abort ();

    pixels = fence_malloc (stride * (unsigned)height);

    if (!pixels)

        return NULL;

    if (stride_fence)

    {

        uint8_t *guard = (uint8_t *)pixels + stride - page_size;

        /* arm row end fence pages */

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

        {

            if (mprotect (guard + i * stride, page_size, PROT_NONE) == -1)

                goto out_fail;

        }

    }

    assert (width >= min_width);

    image = pixman_image_create_bits_no_clear (format, width, height,

                                               pixels, stride);

    if (!image)

        goto out_fail;

    pixman_image_set_destroy_function (image, fence_image_destroy, pixels);

    return image;

out_fail:

    fence_free (pixels);

    return NULL;

}

#else /* FENCE_MALLOC_ACTIVE */

void *

fence_malloc (int64_t len)

{

    return malloc (len);

}

void

fence_free (void *data)

{

    free (data);

}

pixman_image_t *

fence_image_create_bits (pixman_format_code_t format,

                         int min_width,

                         int height,

                         pixman_bool_t stride_fence)

{

    return pixman_image_create_bits (format, min_width, height, NULL, 0);

    /* Implicitly allocated storage does not need a destroy function

     * to get freed on refcount hitting zero.

     */

}

unsigned long

fence_get_page_size ()

{

    return 0;

}

#endif /* FENCE_MALLOC_ACTIVE */

uint8_t *

make_random_bytes (int n_bytes)

{

    uint8_t *bytes = fence_malloc (n_bytes);

    if (!bytes)

	return NULL;

    prng_randmemset (bytes, n_bytes, 0);

    return bytes;

}

void

a8r8g8b8_to_rgba_np (uint32_t *dst, uint32_t *src, int n_pixels)

{

    uint8_t *dst8 = (uint8_t *)dst;

    int i;

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

    {

	uint32_t p = src[i];

	uint8_t a, r, g, b;

	a = (p & 0xff000000) >> 24;

	r = (p & 0x00ff0000) >> 16;

	g = (p & 0x0000ff00) >> 8;

	b = (p & 0x000000ff) >> 0;

	if (a != 0)

	{

#define DIVIDE(c, a)							\

	    do								\

	    {								\

		int t = ((c) * 255) / a;				\

		(c) = t < 0? 0 : t > 255? 255 : t;			\

	    } while (0)

	    DIVIDE (r, a);

	    DIVIDE (g, a);

	    DIVIDE (b, a);

	}

	*dst8++ = r;

	*dst8++ = g;

	*dst8++ = b;

	*dst8++ = a;

    }

}

#ifdef HAVE_LIBPNG

pixman_bool_t

write_png (pixman_image_t *image, const char *filename)

{

    int width = pixman_image_get_width (image);

    int height = pixman_image_get_height (image);

    int stride = width * 4;

    uint32_t *data = malloc (height * stride);

    pixman_image_t *copy;

    png_struct *write_struct;

    png_info *info_struct;

    pixman_bool_t result = FALSE;

    FILE *f = fopen (filename, "wb");

    png_bytep *row_pointers;

    int i;

    if (!f)

	return FALSE;

    row_pointers = malloc (height * sizeof (png_bytep));

    copy = pixman_image_create_bits (

	PIXMAN_a8r8g8b8, width, height, data, stride);

    pixman_image_composite32 (

	PIXMAN_OP_SRC, image, NULL, copy, 0, 0, 0, 0, 0, 0, width, height);

    a8r8g8b8_to_rgba_np (data, data, height * width);

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

	row_pointers[i] = (png_bytep)(data + i * width);

    if (!(write_struct = png_create_write_struct (

	      PNG_LIBPNG_VER_STRING, NULL, NULL, NULL)))

	goto out1;

    if (!(info_struct = png_create_info_struct (write_struct)))

	goto out2;

    png_init_io (write_struct, f);

    png_set_IHDR (write_struct, info_struct, width, height,

		  8, PNG_COLOR_TYPE_RGB_ALPHA,

		  PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE,

		  PNG_FILTER_TYPE_BASE);

    png_write_info (write_struct, info_struct);

    png_write_image (write_struct, row_pointers);

    png_write_end (write_struct, NULL);

    result = TRUE;

out2:

    png_destroy_write_struct (&write_struct, &info_struct);

out1:

    if (fclose (f) != 0)

	result = FALSE;

    pixman_image_unref (copy);

    free (row_pointers);

    free (data);

    return result;

}

#else /* no libpng */

pixman_bool_t

write_png (pixman_image_t *image, const char *filename)

{

    return FALSE;

}

#endif

static void

color8_to_color16 (uint32_t color8, pixman_color_t *color16)

{

    color16->alpha = ((color8 & 0xff000000) >> 24);

    color16->red =   ((color8 & 0x00ff0000) >> 16);

    color16->green = ((color8 & 0x0000ff00) >> 8);

    color16->blue =  ((color8 & 0x000000ff) >> 0);

    color16->alpha |= color16->alpha << 8;

    color16->red   |= color16->red << 8;

    color16->blue  |= color16->blue << 8;

    color16->green |= color16->green << 8;

}

void

draw_checkerboard (pixman_image_t *image,

		   int check_size,

		   uint32_t color1, uint32_t color2)

{

    pixman_color_t check1, check2;

    pixman_image_t *c1, *c2;

    int n_checks_x, n_checks_y;

    int i, j;

    color8_to_color16 (color1, &check1;;

    color8_to_color16 (color2, &check2;;

    c1 = pixman_image_create_solid_fill (&check1;;

    c2 = pixman_image_create_solid_fill (&check2;;

    n_checks_x = (

	pixman_image_get_width (image) + check_size - 1) / check_size;

    n_checks_y = (

	pixman_image_get_height (image) + check_size - 1) / check_size;

    for (j = 0; j < n_checks_y; j++)

    {

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

	{

	    pixman_image_t *src;

	    if (((i ^ j) & 1))

		src = c1;

	    else

		src = c2;

	    pixman_image_composite32 (PIXMAN_OP_SRC, src, NULL, image,

				      0, 0, 0, 0,

				      i * check_size, j * check_size,

				      check_size, check_size);

	}

    }

}

static uint32_t

call_test_function (uint32_t    (*test_function)(int testnum, int verbose),

		    int		testnum,

		    int		verbose)

{

    uint32_t retval;

#if defined (__GNUC__) && defined (_WIN32) && (defined (__i386) || defined (__i386__))

    __asm__ (

	/* Deliberately avoid aligning the stack to 16 bytes */

	"pushl	%1\n\t"

	"pushl	%2\n\t"

	"call	*%3\n\t"

	"addl	$8, %%esp\n\t"

	: "=a" (retval)

	: "r" (verbose),

	  "r" (testnum),

	  "r" (test_function)

	: "edx", "ecx"); /* caller save registers */

#else

    retval = test_function (testnum, verbose);

#endif

    return retval;

}

/*

 * A function, which can be used as a core part of the test programs,

 * intended to detect various problems with the help of fuzzing input

 * to pixman API (according to some templates, aka "smart" fuzzing).

 * Some general information about such testing can be found here:

 * http://en.wikipedia.org/wiki/Fuzz_testing

 *

 * It may help detecting:

 *  - crashes on bad handling of valid or reasonably invalid input to

 *    pixman API.

 *  - deviations from the behavior of older pixman releases.

 *  - deviations from the behavior of the same pixman release, but

 *    configured in a different way (for example with SIMD optimizations

 *    disabled), or running on a different OS or hardware.

 *

 * The test is performed by calling a callback function a huge number

 * of times. The callback function is expected to run some snippet of

 * pixman code with pseudorandom variations to the data feeded to

 * pixman API. A result of running each callback function should be

 * some deterministic value which depends on test number (test number

 * can be used as a seed for PRNG). When 'verbose' argument is nonzero,

 * callback function is expected to print to stdout some information

 * about what it does.

 *

 * Return values from many small tests are accumulated together and

 * used as final checksum, which can be compared to some expected

 * value. Running the tests not individually, but in a batch helps

 * to reduce process start overhead and also allows to parallelize

 * testing and utilize multiple CPU cores.

 *

 * The resulting executable can be run without any arguments. In

 * this case it runs a batch of tests starting from 1 and up to

 * 'default_number_of_iterations'. The resulting checksum is

 * compared with 'expected_checksum' and FAIL or PASS verdict

 * depends on the result of this comparison.

 *

 * If the executable is run with 2 numbers provided as command line

 * arguments, they specify the starting and ending numbers for a test

 * batch.

 *

 * If the executable is run with only one number provided as a command

 * line argument, then this number is used to call the callback function

 * once, and also with verbose flag set.

 */

int

fuzzer_test_main (const char *test_name,

		  int         default_number_of_iterations,

		  uint32_t    expected_checksum,

		  uint32_t    (*test_function)(int testnum, int verbose),

		  int         argc,

		  const char *argv[])

{

    int i, n1 = 1, n2 = 0;

    uint32_t checksum = 0;

    int verbose = getenv ("VERBOSE") != NULL;

    if (argc >= 3)

    {

	n1 = atoi (argv[1]);

	n2 = atoi (argv[2]);

	if (n2 < n1)

	{

	    printf ("invalid test range\n");

	    return 1;

	}

    }

    else if (argc >= 2)

    {

	n2 = atoi (argv[1]);

	checksum = call_test_function (test_function, n2, 1);

	printf ("%d: checksum=%08X\n", n2, checksum);

	return 0;

    }

    else

    {

	n1 = 1;

	n2 = default_number_of_iterations;

    }

#ifdef USE_OPENMP

    #pragma omp parallel for reduction(+:checksum) default(none) \

					shared(n1, n2, test_function, verbose)

#endif

    for (i = n1; i <= n2; i++)

    {

	uint32_t crc = call_test_function (test_function, i, 0);