1 /*-
2  * See the file LICENSE for redistribution information.
3  *
4  * Copyright (c) 1996, 1997, 1998
5  *	Sleepycat Software.  All rights reserved.
6  */
7 #include "config.h"
8 
9 #ifndef lint
10 static const char sccsid[] = "@(#)log_register.c	10.22 (Sleepycat) 9/27/98";
11 #endif /* not lint */
12 
13 #ifndef NO_SYSTEM_INCLUDES
14 #include <sys/types.h>
15 
16 #include <errno.h>
17 #include <string.h>
18 #endif
19 
20 #include "db_int.h"
21 #include "shqueue.h"
22 #include "log.h"
23 #include "common_ext.h"
24 
25 /*
26  * log_register --
27  *	Register a file name.
28  */
29 int
log_register(dblp,dbp,name,type,idp)30 log_register(dblp, dbp, name, type, idp)
31 	DB_LOG *dblp;
32 	DB *dbp;
33 	const char *name;
34 	DBTYPE type;
35 	u_int32_t *idp;
36 {
37 	DBT fid_dbt, r_name;
38 	DB_LSN r_unused;
39 	FNAME *fnp, *reuse_fnp;
40 	size_t len;
41 	u_int32_t maxid;
42 	int inserted, ret;
43 	char *fullname;
44 	void *namep;
45 
46 	inserted = 0;
47 	fullname = NULL;
48 	fnp = namep = reuse_fnp = NULL;
49 
50 	LOG_PANIC_CHECK(dblp);
51 
52 	/* Check the arguments. */
53 	if (type != DB_BTREE && type != DB_HASH && type != DB_RECNO) {
54 		__db_err(dblp->dbenv, "log_register: unknown DB file type");
55 		return (EINVAL);
56 	}
57 
58 	/* Get the log file id. */
59 	if ((ret = __db_appname(dblp->dbenv,
60 	    DB_APP_DATA, NULL, name, 0, NULL, &fullname)) != 0)
61 		return (ret);
62 
63 	LOCK_LOGREGION(dblp);
64 
65 	/*
66 	 * See if we've already got this file in the log, finding the
67 	 * (maximum+1) in-use file id and some available file id (if we
68 	 * find an available fid, we'll use it, else we'll have to allocate
69 	 * one after the maximum that we found).
70 	 */
71 	for (maxid = 0, fnp = SH_TAILQ_FIRST(&dblp->lp->fq, __fname);
72 	    fnp != NULL; fnp = SH_TAILQ_NEXT(fnp, q, __fname)) {
73 		if (fnp->ref == 0) {		/* Entry is not in use. */
74 			if (reuse_fnp == NULL)
75 				reuse_fnp = fnp;
76 			continue;
77 		}
78 		if (!memcmp(dbp->fileid, fnp->ufid, DB_FILE_ID_LEN)) {
79 			++fnp->ref;
80 			goto found;
81 		}
82 		if (maxid <= fnp->id)
83 			maxid = fnp->id + 1;
84 	}
85 
86 	/* Fill in fnp structure. */
87 
88 	if (reuse_fnp != NULL)		/* Reuse existing one. */
89 		fnp = reuse_fnp;
90 	else if ((ret = __db_shalloc(dblp->addr, sizeof(FNAME), 0, &fnp)) != 0)
91 		goto err;
92 	else				/* Allocate a new one. */
93 		fnp->id = maxid;
94 
95 	fnp->ref = 1;
96 	fnp->s_type = type;
97 	memcpy(fnp->ufid, dbp->fileid, DB_FILE_ID_LEN);
98 
99 	len = strlen(name) + 1;
100 	if ((ret = __db_shalloc(dblp->addr, len, 0, &namep)) != 0)
101 		goto err;
102 	fnp->name_off = R_OFFSET(dblp, namep);
103 	memcpy(namep, name, len);
104 
105 	/* Only do the insert if we allocated a new fnp. */
106 	if (reuse_fnp == NULL)
107 		SH_TAILQ_INSERT_HEAD(&dblp->lp->fq, fnp, q, __fname);
108 	inserted = 1;
109 
110 found:	/* Log the registry. */
111 	if (!F_ISSET(dblp, DBC_RECOVER)) {
112 		r_name.data = (void *)name;		/* XXX: Yuck! */
113 		r_name.size = strlen(name) + 1;
114 		memset(&fid_dbt, 0, sizeof(fid_dbt));
115 		fid_dbt.data = dbp->fileid;
116 		fid_dbt.size = DB_FILE_ID_LEN;
117 		if ((ret = __log_register_log(dblp, NULL, &r_unused,
118 		    0, LOG_OPEN, &r_name, &fid_dbt, fnp->id, type)) != 0)
119 			goto err;
120 		if ((ret = __log_add_logid(dblp, dbp, name, fnp->id)) != 0)
121 			goto err;
122 	}
123 
124 	if (0) {
125 err:		/*
126 		 * XXX
127 		 * We should grow the region.
128 		 */
129 		if (inserted)
130 			SH_TAILQ_REMOVE(&dblp->lp->fq, fnp, q, __fname);
131 		if (namep != NULL)
132 			__db_shalloc_free(dblp->addr, namep);
133 		if (fnp != NULL)
134 			__db_shalloc_free(dblp->addr, fnp);
135 	}
136 
137 	if (idp != NULL)
138 		*idp = fnp->id;
139 	UNLOCK_LOGREGION(dblp);
140 
141 	if (fullname != NULL)
142 		__os_freestr(fullname);
143 
144 	return (ret);
145 }
146 
147 /*
148  * log_unregister --
149  *	Discard a registered file name.
150  */
151 int
log_unregister(dblp,fid)152 log_unregister(dblp, fid)
153 	DB_LOG *dblp;
154 	u_int32_t fid;
155 {
156 	DBT fid_dbt, r_name;
157 	DB_LSN r_unused;
158 	FNAME *fnp;
159 	int ret;
160 
161 	LOG_PANIC_CHECK(dblp);
162 
163 	ret = 0;
164 	LOCK_LOGREGION(dblp);
165 
166 	/* Find the entry in the log. */
167 	for (fnp = SH_TAILQ_FIRST(&dblp->lp->fq, __fname);
168 	    fnp != NULL; fnp = SH_TAILQ_NEXT(fnp, q, __fname))
169 		if (fid == fnp->id)
170 			break;
171 	if (fnp == NULL) {
172 		__db_err(dblp->dbenv, "log_unregister: non-existent file id");
173 		ret = EINVAL;
174 		goto ret1;
175 	}
176 
177 	/* Unlog the registry. */
178 	if (!F_ISSET(dblp, DBC_RECOVER)) {
179 		memset(&r_name, 0, sizeof(r_name));
180 		r_name.data = R_ADDR(dblp, fnp->name_off);
181 		r_name.size = strlen(r_name.data) + 1;
182 		memset(&fid_dbt, 0, sizeof(fid_dbt));
183 		fid_dbt.data = fnp->ufid;
184 		fid_dbt.size = DB_FILE_ID_LEN;
185 		if ((ret = __log_register_log(dblp, NULL, &r_unused,
186 		    0, LOG_CLOSE, &r_name, &fid_dbt, fid, fnp->s_type)) != 0)
187 			goto ret1;
188 	}
189 
190 	/*
191 	 * If more than 1 reference, just decrement the reference and return.
192 	 * Otherwise, free the name.
193 	 */
194 	--fnp->ref;
195 	if (fnp->ref == 0)
196 		__db_shalloc_free(dblp->addr, R_ADDR(dblp, fnp->name_off));
197 
198 	/*
199 	 * Remove from the process local table.  If this operation is taking
200 	 * place during recovery, then the logid was never added to the table,
201 	 * so do not remove it.
202 	 */
203 	if (!F_ISSET(dblp, DBC_RECOVER))
204 		__log_rem_logid(dblp, fid);
205 
206 ret1:	UNLOCK_LOGREGION(dblp);
207 	return (ret);
208 }
209