contrib/diagnose_corruption/check_flipped_bits.c - platform/external/zstd - Git at Google

 /*
  * Copyright (c) 2019-present, Facebook, Inc.
  * All rights reserved.
  *
  * This source code is licensed under both the BSD-style license (found in the
  * LICENSE file in the root directory of this source tree) and the GPLv2 (found
  * in the COPYING file in the root directory of this source tree).
  * You may select, at your option, one of the above-listed licenses.
  */

 #define ZSTD_STATIC_LINKING_ONLY
 #include "zstd.h"
 #include "zstd_errors.h"

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <unistd.h>

 typedef struct {
   char *input;
   size_t input_size;

   char *perturbed; /* same size as input */

   char *output;
   size_t output_size;

   const char *dict_file_name;
   const char *dict_file_dir_name;
   int32_t dict_id;
   char *dict;
   size_t dict_size;
   ZSTD_DDict* ddict;

   ZSTD_DCtx* dctx;

   int success_count;
   int error_counts[ZSTD_error_maxCode];
 } stuff_t;

 static void free_stuff(stuff_t* stuff) {
   free(stuff->input);
   free(stuff->output);
   ZSTD_freeDDict(stuff->ddict);
   free(stuff->dict);
   ZSTD_freeDCtx(stuff->dctx);
 }

 static void usage(void) {
   fprintf(stderr, "check_flipped_bits input_filename [-d dict] [-D dict_dir]\n");
   fprintf(stderr, "\n");
   fprintf(stderr, "Arguments:\n");
   fprintf(stderr, "    -d file: path to a dictionary file to use.\n");
   fprintf(stderr, "    -D dir : path to a directory, with files containing dictionaries, of the\n"
                   "             form DICTID.zstd-dict, e.g., 12345.zstd-dict.\n");
   exit(1);
 }

 static void print_summary(stuff_t* stuff) {
   int error_code;
   fprintf(stderr, "%9d successful decompressions\n", stuff->success_count);
   for (error_code = 0; error_code < ZSTD_error_maxCode; error_code++) {
     int count = stuff->error_counts[error_code];
     if (count) {
       fprintf(
           stderr, "%9d failed decompressions with message: %s\n",
           count, ZSTD_getErrorString(error_code));
     }
   }
 }

 static char* readFile(const char* filename, size_t* size) {
   struct stat statbuf;
   int ret;
   FILE* f;
   char *buf;
   size_t bytes_read;

   ret = stat(filename, &statbuf);
   if (ret != 0) {
     fprintf(stderr, "stat failed: %m\n");
     return NULL;
   }
   if ((statbuf.st_mode & S_IFREG) != S_IFREG) {
     fprintf(stderr, "Input must be regular file\n");
     return NULL;
   }

   *size = statbuf.st_size;

   f = fopen(filename, "r");
   if (f == NULL) {
     fprintf(stderr, "fopen failed: %m\n");
     return NULL;
   }

   buf = malloc(*size);
   if (buf == NULL) {
     fprintf(stderr, "malloc failed\n");
     fclose(f);
     return NULL;
   }

   bytes_read = fread(buf, 1, *size, f);
   if (bytes_read != *size) {
     fprintf(stderr, "failed to read whole file\n");
     fclose(f);
     free(buf);
     return NULL;
   }

   ret = fclose(f);
   if (ret != 0) {
     fprintf(stderr, "fclose failed: %m\n");
     free(buf);
     return NULL;
   }

   return buf;
 }

 static ZSTD_DDict* readDict(const char* filename, char **buf, size_t* size, int32_t* dict_id) {
   ZSTD_DDict* ddict;
   *buf = readFile(filename, size);
   if (*buf == NULL) {
     fprintf(stderr, "Opening dictionary file '%s' failed\n", filename);
     return NULL;
   }

   ddict = ZSTD_createDDict_advanced(*buf, *size, ZSTD_dlm_byRef, ZSTD_dct_auto, ZSTD_defaultCMem);
   if (ddict == NULL) {
     fprintf(stderr, "Failed to create ddict.\n");
     return NULL;
   }
   if (dict_id != NULL) {
     *dict_id = ZSTD_getDictID_fromDDict(ddict);
   }
   return ddict;
 }

 static ZSTD_DDict* readDictByID(stuff_t *stuff, int32_t dict_id, char **buf, size_t* size) {
   if (stuff->dict_file_dir_name == NULL) {
     return NULL;
   } else {
     size_t dir_name_len = strlen(stuff->dict_file_dir_name);
     int dir_needs_separator = 0;
     size_t dict_file_name_alloc_size = dir_name_len + 1 /* '/' */ + 10 /* max int32_t len */ + strlen(".zstd-dict") + 1 /* '\0' */;
     char *dict_file_name = malloc(dict_file_name_alloc_size);
     ZSTD_DDict* ddict;
     int32_t read_dict_id;
     if (dict_file_name == NULL) {
       fprintf(stderr, "malloc failed.\n");
       return 0;
     }

     if (dir_name_len > 0 && stuff->dict_file_dir_name[dir_name_len - 1] != '/') {
       dir_needs_separator = 1;
     }

     snprintf(
       dict_file_name,
       dict_file_name_alloc_size,
       "%s%s%u.zstd-dict",
       stuff->dict_file_dir_name,
       dir_needs_separator ? "/" : "",
       dict_id);

     /* fprintf(stderr, "Loading dict %u from '%s'.\n", dict_id, dict_file_name); */

     ddict = readDict(dict_file_name, buf, size, &read_dict_id);
     if (ddict == NULL) {
       fprintf(stderr, "Failed to create ddict from '%s'.\n", dict_file_name);
       free(dict_file_name);
       return 0;
     }
     if (read_dict_id != dict_id) {
       fprintf(stderr, "Read dictID (%u) does not match expected (%u).\n", read_dict_id, dict_id);
       free(dict_file_name);
       ZSTD_freeDDict(ddict);
       return 0;
     }

     free(dict_file_name);
     return ddict;
   }
 }

 static int init_stuff(stuff_t* stuff, int argc, char *argv[]) {
   const char* input_filename;

   if (argc < 2) {
     usage();
   }

   input_filename = argv[1];
   stuff->input_size = 0;
   stuff->input = readFile(input_filename, &stuff->input_size);
   if (stuff->input == NULL) {
     fprintf(stderr, "Failed to read input file.\n");
     return 0;
   }

   stuff->perturbed = malloc(stuff->input_size);
   if (stuff->perturbed == NULL) {
     fprintf(stderr, "malloc failed.\n");
     return 0;
   }
   memcpy(stuff->perturbed, stuff->input, stuff->input_size);

   stuff->output_size = ZSTD_DStreamOutSize();
   stuff->output = malloc(stuff->output_size);
   if (stuff->output == NULL) {
     fprintf(stderr, "malloc failed.\n");
     return 0;
   }

   stuff->dict_file_name = NULL;
   stuff->dict_file_dir_name = NULL;
   stuff->dict_id = 0;
   stuff->dict = NULL;
   stuff->dict_size = 0;
   stuff->ddict = NULL;

   if (argc > 2) {
     if (!strcmp(argv[2], "-d")) {
       if (argc > 3) {
         stuff->dict_file_name = argv[3];
       } else {
         usage();
       }
     } else
     if (!strcmp(argv[2], "-D")) {
       if (argc > 3) {
         stuff->dict_file_dir_name = argv[3];
       } else {
         usage();
       }
     } else {
       usage();
     }
   }

   if (stuff->dict_file_dir_name) {
     int32_t dict_id = ZSTD_getDictID_fromFrame(stuff->input, stuff->input_size);
     if (dict_id != 0) {
       stuff->ddict = readDictByID(stuff, dict_id, &stuff->dict, &stuff->dict_size);
       if (stuff->ddict == NULL) {
         fprintf(stderr, "Failed to create cached ddict.\n");
         return 0;
       }
       stuff->dict_id = dict_id;
     }
   } else
   if (stuff->dict_file_name) {
     stuff->ddict = readDict(stuff->dict_file_name, &stuff->dict, &stuff->dict_size, &stuff->dict_id);
     if (stuff->ddict == NULL) {
       fprintf(stderr, "Failed to create ddict from '%s'.\n", stuff->dict_file_name);
       return 0;
     }
   }

   stuff->dctx = ZSTD_createDCtx();
   if (stuff->dctx == NULL) {
     return 0;
   }

   stuff->success_count = 0;
   memset(stuff->error_counts, 0, sizeof(stuff->error_counts));

   return 1;
 }

 static int test_decompress(stuff_t* stuff) {
   size_t ret;
   ZSTD_inBuffer in = {stuff->perturbed, stuff->input_size, 0};
   ZSTD_outBuffer out = {stuff->output, stuff->output_size, 0};
   ZSTD_DCtx* dctx = stuff->dctx;
   int32_t custom_dict_id = ZSTD_getDictID_fromFrame(in.src, in.size);
   char *custom_dict = NULL;
   size_t custom_dict_size = 0;
   ZSTD_DDict* custom_ddict = NULL;

   if (custom_dict_id != 0 && custom_dict_id != stuff->dict_id) {
     /* fprintf(stderr, "Instead of dict %u, this perturbed blob wants dict %u.\n", stuff->dict_id, custom_dict_id); */
     custom_ddict = readDictByID(stuff, custom_dict_id, &custom_dict, &custom_dict_size);
   }

   ZSTD_DCtx_reset(dctx, ZSTD_reset_session_only);

   if (custom_ddict != NULL) {
     ZSTD_DCtx_refDDict(dctx, custom_ddict);
   } else {
     ZSTD_DCtx_refDDict(dctx, stuff->ddict);
   }

   while (in.pos != in.size) {
     out.pos = 0;
     ret = ZSTD_decompressStream(dctx, &out, &in);

     if (ZSTD_isError(ret)) {
       unsigned int code = ZSTD_getErrorCode(ret);
       if (code >= ZSTD_error_maxCode) {
         fprintf(stderr, "Received unexpected error code!\n");
         exit(1);
       }
       stuff->error_counts[code]++;
       /*
       fprintf(
           stderr, "Decompression failed: %s\n", ZSTD_getErrorName(ret));
       */
       if (custom_ddict != NULL) {
         ZSTD_freeDDict(custom_ddict);
         free(custom_dict);
       }
       return 0;
     }
   }

   stuff->success_count++;

   if (custom_ddict != NULL) {
     ZSTD_freeDDict(custom_ddict);
     free(custom_dict);
   }
   return 1;
 }

 static int perturb_bits(stuff_t* stuff) {
   size_t pos;
   size_t bit;
   for (pos = 0; pos < stuff->input_size; pos++) {
     unsigned char old_val = stuff->input[pos];
     if (pos % 1000 == 0) {
       fprintf(stderr, "Perturbing byte %zu / %zu\n", pos, stuff->input_size);
     }
     for (bit = 0; bit < 8; bit++) {
       unsigned char new_val = old_val ^ (1 << bit);
       stuff->perturbed[pos] = new_val;
       if (test_decompress(stuff)) {
         fprintf(
             stderr,
             "Flipping byte %zu bit %zu (0x%02x -> 0x%02x) "
             "produced a successful decompression!\n",
             pos, bit, old_val, new_val);
       }
     }
     stuff->perturbed[pos] = old_val;
   }
   return 1;
 }

 static int perturb_bytes(stuff_t* stuff) {
   size_t pos;
   size_t new_val;
   for (pos = 0; pos < stuff->input_size; pos++) {
     unsigned char old_val = stuff->input[pos];
     if (pos % 1000 == 0) {
       fprintf(stderr, "Perturbing byte %zu / %zu\n", pos, stuff->input_size);
     }
     for (new_val = 0; new_val < 256; new_val++) {
       stuff->perturbed[pos] = new_val;
       if (test_decompress(stuff)) {
         fprintf(
             stderr,
             "Changing byte %zu (0x%02x -> 0x%02x) "
             "produced a successful decompression!\n",
             pos, old_val, (unsigned char)new_val);
       }
     }
     stuff->perturbed[pos] = old_val;
   }
   return 1;
 }

 int main(int argc, char* argv[]) {
   stuff_t stuff;

   if(!init_stuff(&stuff, argc, argv)) {
     fprintf(stderr, "Failed to init.\n");
     return 1;
   }

   if (test_decompress(&stuff)) {
     fprintf(stderr, "Blob already decompresses successfully!\n");
     return 1;
   }

   perturb_bits(&stuff);

   perturb_bytes(&stuff);

   print_summary(&stuff);

   free_stuff(&stuff);

   return 0;
 }
	/*
	* Copyright (c) 2019-present, Facebook, Inc.
	* All rights reserved.
	*
	* This source code is licensed under both the BSD-style license (found in the
	* LICENSE file in the root directory of this source tree) and the GPLv2 (found
	* in the COPYING file in the root directory of this source tree).
	* You may select, at your option, one of the above-listed licenses.
	*/

	#define ZSTD_STATIC_LINKING_ONLY
	#include "zstd.h"
	#include "zstd_errors.h"

	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <sys/types.h>
	#include <sys/stat.h>
	#include <unistd.h>

	typedef struct {
	char *input;
	size_t input_size;

	char perturbed; / same size as input */

	char *output;
	size_t output_size;

	const char *dict_file_name;
	const char *dict_file_dir_name;
	int32_t dict_id;
	char *dict;
	size_t dict_size;
	ZSTD_DDict* ddict;

	ZSTD_DCtx* dctx;

	int success_count;
	int error_counts[ZSTD_error_maxCode];
	} stuff_t;

	static void free_stuff(stuff_t* stuff) {
	free(stuff->input);
	free(stuff->output);
	ZSTD_freeDDict(stuff->ddict);
	free(stuff->dict);
	ZSTD_freeDCtx(stuff->dctx);
	}

	static void usage(void) {
	fprintf(stderr, "check_flipped_bits input_filename [-d dict] [-D dict_dir]\n");
	fprintf(stderr, "\n");
	fprintf(stderr, "Arguments:\n");
	fprintf(stderr, " -d file: path to a dictionary file to use.\n");
	fprintf(stderr, " -D dir : path to a directory, with files containing dictionaries, of the\n"
	" form DICTID.zstd-dict, e.g., 12345.zstd-dict.\n");
	exit(1);
	}

	static void print_summary(stuff_t* stuff) {
	int error_code;
	fprintf(stderr, "%9d successful decompressions\n", stuff->success_count);
	for (error_code = 0; error_code < ZSTD_error_maxCode; error_code++) {
	int count = stuff->error_counts[error_code];
	if (count) {
	fprintf(
	stderr, "%9d failed decompressions with message: %s\n",
	count, ZSTD_getErrorString(error_code));
	}
	}
	}

	static char* readFile(const char* filename, size_t* size) {
	struct stat statbuf;
	int ret;
	FILE* f;
	char *buf;
	size_t bytes_read;

	ret = stat(filename, &statbuf);
	if (ret != 0) {
	fprintf(stderr, "stat failed: %m\n");
	return NULL;
	}
	if ((statbuf.st_mode & S_IFREG) != S_IFREG) {
	fprintf(stderr, "Input must be regular file\n");
	return NULL;
	}

	*size = statbuf.st_size;

	f = fopen(filename, "r");
	if (f == NULL) {
	fprintf(stderr, "fopen failed: %m\n");
	return NULL;
	}

	buf = malloc(*size);
	if (buf == NULL) {
	fprintf(stderr, "malloc failed\n");
	fclose(f);
	return NULL;
	}

	bytes_read = fread(buf, 1, *size, f);
	if (bytes_read != *size) {
	fprintf(stderr, "failed to read whole file\n");
	fclose(f);
	free(buf);
	return NULL;
	}

	ret = fclose(f);
	if (ret != 0) {
	fprintf(stderr, "fclose failed: %m\n");
	free(buf);
	return NULL;
	}

	return buf;
	}

	static ZSTD_DDict* readDict(const char* filename, char *buf, size_t size, int32_t* dict_id) {
	ZSTD_DDict* ddict;
	*buf = readFile(filename, size);
	if (*buf == NULL) {
	fprintf(stderr, "Opening dictionary file '%s' failed\n", filename);
	return NULL;
	}

	ddict = ZSTD_createDDict_advanced(buf, size, ZSTD_dlm_byRef, ZSTD_dct_auto, ZSTD_defaultCMem);
	if (ddict == NULL) {
	fprintf(stderr, "Failed to create ddict.\n");
	return NULL;
	}
	if (dict_id != NULL) {
	*dict_id = ZSTD_getDictID_fromDDict(ddict);
	}
	return ddict;
	}

	static ZSTD_DDict* readDictByID(stuff_t stuff, int32_t dict_id, char buf, size_t size) {
	if (stuff->dict_file_dir_name == NULL) {
	return NULL;
	} else {
	size_t dir_name_len = strlen(stuff->dict_file_dir_name);
	int dir_needs_separator = 0;
	size_t dict_file_name_alloc_size = dir_name_len + 1 /* '/' / + 10 / max int32_t len / + strlen(".zstd-dict") + 1 / '\0' */;
	char *dict_file_name = malloc(dict_file_name_alloc_size);
	ZSTD_DDict* ddict;
	int32_t read_dict_id;
	if (dict_file_name == NULL) {
	fprintf(stderr, "malloc failed.\n");
	return 0;
	}

	if (dir_name_len > 0 && stuff->dict_file_dir_name[dir_name_len - 1] != '/') {
	dir_needs_separator = 1;
	}

	snprintf(
	dict_file_name,
	dict_file_name_alloc_size,
	"%s%s%u.zstd-dict",
	stuff->dict_file_dir_name,
	dir_needs_separator ? "/" : "",
	dict_id);

	/* fprintf(stderr, "Loading dict %u from '%s'.\n", dict_id, dict_file_name); */

	ddict = readDict(dict_file_name, buf, size, &read_dict_id);
	if (ddict == NULL) {
	fprintf(stderr, "Failed to create ddict from '%s'.\n", dict_file_name);
	free(dict_file_name);
	return 0;
	}
	if (read_dict_id != dict_id) {
	fprintf(stderr, "Read dictID (%u) does not match expected (%u).\n", read_dict_id, dict_id);
	free(dict_file_name);
	ZSTD_freeDDict(ddict);
	return 0;
	}

	free(dict_file_name);
	return ddict;
	}
	}

	static int init_stuff(stuff_t* stuff, int argc, char *argv[]) {
	const char* input_filename;

	if (argc < 2) {
	usage();
	}

	input_filename = argv[1];
	stuff->input_size = 0;
	stuff->input = readFile(input_filename, &stuff->input_size);
	if (stuff->input == NULL) {
	fprintf(stderr, "Failed to read input file.\n");
	return 0;
	}

	stuff->perturbed = malloc(stuff->input_size);
	if (stuff->perturbed == NULL) {
	fprintf(stderr, "malloc failed.\n");
	return 0;
	}
	memcpy(stuff->perturbed, stuff->input, stuff->input_size);

	stuff->output_size = ZSTD_DStreamOutSize();
	stuff->output = malloc(stuff->output_size);
	if (stuff->output == NULL) {
	fprintf(stderr, "malloc failed.\n");
	return 0;
	}

	stuff->dict_file_name = NULL;
	stuff->dict_file_dir_name = NULL;
	stuff->dict_id = 0;
	stuff->dict = NULL;
	stuff->dict_size = 0;
	stuff->ddict = NULL;

	if (argc > 2) {
	if (!strcmp(argv[2], "-d")) {
	if (argc > 3) {
	stuff->dict_file_name = argv[3];
	} else {
	usage();
	}
	} else
	if (!strcmp(argv[2], "-D")) {
	if (argc > 3) {
	stuff->dict_file_dir_name = argv[3];
	} else {
	usage();
	}
	} else {
	usage();
	}
	}

	if (stuff->dict_file_dir_name) {
	int32_t dict_id = ZSTD_getDictID_fromFrame(stuff->input, stuff->input_size);
	if (dict_id != 0) {
	stuff->ddict = readDictByID(stuff, dict_id, &stuff->dict, &stuff->dict_size);
	if (stuff->ddict == NULL) {
	fprintf(stderr, "Failed to create cached ddict.\n");
	return 0;
	}
	stuff->dict_id = dict_id;
	}
	} else
	if (stuff->dict_file_name) {
	stuff->ddict = readDict(stuff->dict_file_name, &stuff->dict, &stuff->dict_size, &stuff->dict_id);
	if (stuff->ddict == NULL) {
	fprintf(stderr, "Failed to create ddict from '%s'.\n", stuff->dict_file_name);
	return 0;
	}
	}

	stuff->dctx = ZSTD_createDCtx();
	if (stuff->dctx == NULL) {
	return 0;
	}

	stuff->success_count = 0;
	memset(stuff->error_counts, 0, sizeof(stuff->error_counts));

	return 1;
	}

	static int test_decompress(stuff_t* stuff) {
	size_t ret;
	ZSTD_inBuffer in = {stuff->perturbed, stuff->input_size, 0};
	ZSTD_outBuffer out = {stuff->output, stuff->output_size, 0};
	ZSTD_DCtx* dctx = stuff->dctx;
	int32_t custom_dict_id = ZSTD_getDictID_fromFrame(in.src, in.size);
	char *custom_dict = NULL;
	size_t custom_dict_size = 0;
	ZSTD_DDict* custom_ddict = NULL;

	if (custom_dict_id != 0 && custom_dict_id != stuff->dict_id) {
	/* fprintf(stderr, "Instead of dict %u, this perturbed blob wants dict %u.\n", stuff->dict_id, custom_dict_id); */
	custom_ddict = readDictByID(stuff, custom_dict_id, &custom_dict, &custom_dict_size);
	}

	ZSTD_DCtx_reset(dctx, ZSTD_reset_session_only);

	if (custom_ddict != NULL) {
	ZSTD_DCtx_refDDict(dctx, custom_ddict);
	} else {
	ZSTD_DCtx_refDDict(dctx, stuff->ddict);
	}

	while (in.pos != in.size) {
	out.pos = 0;
	ret = ZSTD_decompressStream(dctx, &out, &in);

	if (ZSTD_isError(ret)) {
	unsigned int code = ZSTD_getErrorCode(ret);
	if (code >= ZSTD_error_maxCode) {
	fprintf(stderr, "Received unexpected error code!\n");
	exit(1);
	}
	stuff->error_counts[code]++;
	/*
	fprintf(
	stderr, "Decompression failed: %s\n", ZSTD_getErrorName(ret));
	*/
	if (custom_ddict != NULL) {
	ZSTD_freeDDict(custom_ddict);
	free(custom_dict);
	}
	return 0;
	}
	}

	stuff->success_count++;

	if (custom_ddict != NULL) {
	ZSTD_freeDDict(custom_ddict);
	free(custom_dict);
	}
	return 1;
	}

	static int perturb_bits(stuff_t* stuff) {
	size_t pos;
	size_t bit;
	for (pos = 0; pos < stuff->input_size; pos++) {
	unsigned char old_val = stuff->input[pos];
	if (pos % 1000 == 0) {
	fprintf(stderr, "Perturbing byte %zu / %zu\n", pos, stuff->input_size);
	}
	for (bit = 0; bit < 8; bit++) {
	unsigned char new_val = old_val ^ (1 << bit);
	stuff->perturbed[pos] = new_val;
	if (test_decompress(stuff)) {
	fprintf(
	stderr,
	"Flipping byte %zu bit %zu (0x%02x -> 0x%02x) "
	"produced a successful decompression!\n",
	pos, bit, old_val, new_val);
	}
	}
	stuff->perturbed[pos] = old_val;
	}
	return 1;
	}

	static int perturb_bytes(stuff_t* stuff) {
	size_t pos;
	size_t new_val;
	for (pos = 0; pos < stuff->input_size; pos++) {
	unsigned char old_val = stuff->input[pos];
	if (pos % 1000 == 0) {
	fprintf(stderr, "Perturbing byte %zu / %zu\n", pos, stuff->input_size);
	}
	for (new_val = 0; new_val < 256; new_val++) {
	stuff->perturbed[pos] = new_val;
	if (test_decompress(stuff)) {
	fprintf(
	stderr,
	"Changing byte %zu (0x%02x -> 0x%02x) "
	"produced a successful decompression!\n",
	pos, old_val, (unsigned char)new_val);
	}
	}
	stuff->perturbed[pos] = old_val;
	}
	return 1;
	}

	int main(int argc, char* argv[]) {
	stuff_t stuff;

	if(!init_stuff(&stuff, argc, argv)) {
	fprintf(stderr, "Failed to init.\n");
	return 1;
	}

	if (test_decompress(&stuff)) {
	fprintf(stderr, "Blob already decompresses successfully!\n");
	return 1;
	}

	perturb_bits(&stuff);

	perturb_bytes(&stuff);

	print_summary(&stuff);

	free_stuff(&stuff);

	return 0;
	}