contrib/sendmail-8.14/libsm/b-strcmp.c

   1 /*
   2  * Copyright (c) 2000-2001, 2004 Sendmail, Inc. and its suppliers.
   3  *      All rights reserved.
   4  *
   5  * By using this file, you agree to the terms and conditions set
   6  * forth in the LICENSE file which can be found at the top level of
   7  * the sendmail distribution.
   8  */
   9
  10 #include <sm/gen.h>
  11 SM_RCSID("@(#)$Id: b-strcmp.c,v 1.14 2005/06/14 23:07:20 ca Exp $")
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <unistd.h>
  15 #include <sys/types.h>
  16 #include <sm/time.h>
  17 #include <sm/string.h>
  18
  19 #define toseconds(x, y) (x.tv_sec - y.tv_sec)
  20 #define SIZE    512
  21 #define LOOPS   4000000L        /* initial number of loops */
  22 #define MAXTIME 30L     /* "maximum" time to run single test */
  23
  24 void fatal __P((char *));
  25 void purpose __P((void));
  26 int main __P((int, char *[]));
  27
  28 void
  29 fatal(str)
  30         char *str;
  31 {
  32         perror(str);
  33         exit(1);
  34 }
  35
  36 void
  37 purpose()
  38 {
  39         printf("This program benchmarks the performance differences between\n");
  40         printf("strcasecmp() and sm_strcasecmp().\n");
  41         printf("These tests may take several minutes to complete.\n");
  42 }
  43
  44 int
  45 main(argc, argv)
  46         int argc;
  47         char *argv[];
  48 {
  49         long a;
  50         int k;
  51         bool doit = false;
  52         long loops;
  53         long j;
  54         long one, two;
  55         struct timeval t1, t2;
  56         char src1[SIZE], src2[SIZE];
  57
  58 # define OPTIONS        "d"
  59         while ((k = getopt(argc, argv, OPTIONS)) != -1)
  60         {
  61                 switch ((char) k)
  62                 {
  63                   case 'd':
  64                         doit = true;
  65                         break;
  66
  67                   default:
  68                         break;
  69                 }
  70         }
  71
  72         if (!doit)
  73         {
  74                 purpose();
  75                 printf("If you want to run it, specify -d as option.\n");
  76                 return 0;
  77         }
  78
  79         /* Run-time comments to the user */
  80         purpose();
  81         printf("\n");
  82         for (k = 0; k < 3; k++)
  83         {
  84                 switch (k)
  85                 {
  86                   case 0:
  87                         (void) sm_strlcpy(src1, "1234567890", SIZE);
  88                         (void) sm_strlcpy(src2, "1234567890", SIZE);
  89                         break;
  90                   case 1:
  91                         (void) sm_strlcpy(src1, "1234567890", SIZE);
  92                         (void) sm_strlcpy(src2, "1234567891", SIZE);
  93                         break;
  94                   case 2:
  95                         (void) sm_strlcpy(src1, "1234567892", SIZE);
  96                         (void) sm_strlcpy(src2, "1234567891", SIZE);
  97                         break;
  98                 }
  99                 printf("Test %d: strcasecmp(%s, %s) versus sm_strcasecmp()\n",
 100                         k, src1, src2);
 101                 loops = LOOPS;
 102                 for (;;)
 103                 {
 104                         j = 0;
 105                         if (gettimeofday(&t1, NULL) < 0)
 106                                 fatal("gettimeofday");
 107                         for (a = 0; a < loops; a++)
 108                                 j += strcasecmp(src1, src2);
 109                         if (gettimeofday(&t2, NULL) < 0)
 110                                 fatal("gettimeofday");
 111                         one = toseconds(t2, t1);
 112                         printf("\tstrcasecmp() result: %ld seconds [%ld]\n",
 113                                 one, j);
 114
 115                         j = 0;
 116                         if (gettimeofday(&t1, NULL) < 0)
 117                                 fatal("gettimeofday");
 118                         for (a = 0; a < loops; a++)
 119                                 j += sm_strcasecmp(src1, src2);
 120                         if (gettimeofday(&t2, NULL) < 0)
 121                                 fatal("gettimeofday");
 122                         two = toseconds(t2, t1);
 123                         printf("\tsm_strcasecmp() result: %ld seconds [%ld]\n",
 124                                 two, j);
 125
 126                         if (abs(one - two) > 2)
 127                                 break;
 128                         loops += loops;
 129                         if (loops < 0L || one > MAXTIME)
 130                         {
 131                                 printf("\t\t** results too close: no decision\n");
 132                                 break;
 133                         }
 134                         else
 135                         {
 136                                 printf("\t\t** results too close redoing test %ld times **\n",
 137                                         loops);
 138                         }
 139                 }
 140         }
 141
 142         printf("\n\n");
 143         printf("Interpreting the results:\n");
 144         printf("\tFor differences larger than 2 seconds, the lower value is\n");
 145         printf("\tbetter and that function should be used for performance\n");
 146         printf("\treasons.\n\n");
 147         printf("This program will re-run the tests when the difference is\n");
 148         printf("less than 2 seconds.\n");
 149         printf("The result will vary depending on the compiler optimization\n");        printf("level used. Compiling the sendmail libsm library with a\n");
 150         printf("better optimization level can change the results.\n");
 151         return 0;
 152 }