t.c

mysql数据库源代码

#include <sys/types.h>

#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "db_185.h"

void	err(char *);
int	mycmp(const DBT *, const DBT *);
void	ops(DB *, int);

int
main()
{
	DB *dbp;
	HASHINFO h_info;
	BTREEINFO b_info;
	RECNOINFO r_info;

	printf("\tBtree...\n");
	memset(&b_info, 0, sizeof(b_info));
	b_info.flags = R_DUP;
	b_info.cachesize = 100 * 1024;
	b_info.psize = 512;
	b_info.lorder = 4321;
	b_info.compare = mycmp;
	(void)remove("a.db");
	if ((dbp =
	   dbopen("a.db", O_CREAT | O_RDWR, 0664, DB_BTREE, &b_info)) == NULL)
		err("dbopen: btree");
	ops(dbp, DB_BTREE);

	printf("\tHash...\n");
	memset(&h_info, 0, sizeof(h_info));
	h_info.bsize = 512;
	h_info.ffactor = 6;
	h_info.nelem = 1000;
	h_info.cachesize = 100 * 1024;
	h_info.lorder = 1234;
	(void)remove("a.db");
	if ((dbp =
	    dbopen("a.db", O_CREAT | O_RDWR, 0664, DB_HASH, &h_info)) == NULL)
		err("dbopen: hash");
	ops(dbp, DB_HASH);

	printf("\tRecno...\n");
	memset(&r_info, 0, sizeof(r_info));
	r_info.flags = R_FIXEDLEN;
	r_info.cachesize = 100 * 1024;
	r_info.psize = 1024;
	r_info.reclen = 37;
	(void)remove("a.db");
	if ((dbp =
	   dbopen("a.db", O_CREAT | O_RDWR, 0664, DB_RECNO, &r_info)) == NULL)
		err("dbopen: recno");
	ops(dbp, DB_RECNO);

	return (0);
}

int
mycmp(a, b)
	const DBT *a, *b;
{
	size_t len;
	u_int8_t *p1, *p2;

	len = a->size > b->size ? b->size : a->size;
	for (p1 = a->data, p2 = b->data; len--; ++p1, ++p2)
		if (*p1 != *p2)
			return ((long)*p1 - (long)*p2);
	return ((long)a->size - (long)b->size);
}

void
ops(dbp, type)
	DB *dbp;
	int type;
{
	FILE *outfp;
	DBT key, data;
	recno_t recno;
	int i, ret;
	char buf[64];

	memset(&key, 0, sizeof(key));
	memset(&data, 0, sizeof(data));

	for (i = 1; i < 100; ++i) {		/* Test DB->put. */
		sprintf(buf, "abc_%d_efg", i);
		if (type == DB_RECNO) {
			recno = i;
			key.data = &recno;
			key.size = sizeof(recno);
		} else {
			key.data = data.data = buf;
			key.size = data.size = strlen(buf);
		}

		data.data = buf;
		data.size = strlen(buf);
		if (dbp->put(dbp, &key, &data, 0))
			err("DB->put");
	}

	if (type == DB_RECNO) {			/* Test DB->get. */
		recno = 97;
		key.data = &recno;
		key.size = sizeof(recno);
	} else {
		key.data = buf;
		key.size = strlen(buf);
	}
	sprintf(buf, "abc_%d_efg", 97);
	if (dbp->get(dbp, &key, &data, 0) != 0)
		err("DB->get");
	if (memcmp(data.data, buf, strlen(buf)))
		err("DB->get: wrong data returned");

	if (type == DB_RECNO) {			/* Test DB->put no-overwrite. */
		recno = 42;
		key.data = &recno;
		key.size = sizeof(recno);
	} else {
		key.data = buf;
		key.size = strlen(buf);
	}
	sprintf(buf, "abc_%d_efg", 42);
	if (dbp->put(dbp, &key, &data, R_NOOVERWRITE) == 0)
		err("DB->put: no-overwrite succeeded");

	if (type == DB_RECNO) {			/* Test DB->del. */
		recno = 35;
		key.data = &recno;
		key.size = sizeof(recno);
	} else {
		sprintf(buf, "abc_%d_efg", 35);
		key.data = buf;
		key.size = strlen(buf);
	}
	if (dbp->del(dbp, &key, 0))
		err("DB->del");

						/* Test DB->seq. */
	if ((outfp = fopen("output", "w")) == NULL)
		err("fopen: output");
	while ((ret = dbp->seq(dbp, &key, &data, R_NEXT)) == 0) {
		if (type == DB_RECNO)
			fprintf(outfp, "%d\n", *(int *)key.data);
		else
			fprintf(outfp,
			    "%.*s\n", (int)key.size, (char *)key.data);
		fprintf(outfp, "%.*s\n", (int)data.size, (char *)data.data);
	}
	if (ret != 1)
		err("DB->seq");
	fclose(outfp);
	switch (type) {
	case DB_BTREE:
		ret = system("cmp output O.BH");
		break;
	case DB_HASH:
		ret = system("sort output | cmp - O.BH");
		break;
	case DB_RECNO:
		ret = system("cmp output O.R");
		break;
	}
	if (ret != 0)
		err("output comparison failed");

	if (dbp->sync(dbp, 0))			/* Test DB->sync. */
		err("DB->sync");

	if (dbp->close(dbp))			/* Test DB->close. */
		err("DB->close");
}

void
err(s)
	char *s;
{
	fprintf(stderr, "\t%s: %s\n", s, strerror(errno));
	exit (1);
}