xref: /freebsd/contrib/sendmail/libsm/b-strcmp.c (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
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 }
153