2 * Copyright 2000, International Business Machines Corporation and others.
5 * This software has been released under the terms of the IBM Public
6 * License. For details, see the LICENSE file in the top-level source
7 * directory or online at http://www.openafs.org/dl/license10.html
10 #include <afsconfig.h>
11 #include <afs/param.h>
18 #include <afs/afsutil.h>
20 #define UBIK_INTERNALS 1
24 * These routines are called via the proc ptr in the ubik_dbase structure. They provide access to
25 * the physical disk, by converting the file numbers being processed ( >= 0 for user data space, < 0
26 * for ubik system files, such as the log) to actual pathnames to open, read, write, truncate, sync,
31 static struct fdcache {
35 } fdcache[MAXFDCACHE];
37 /* Cache a stdio handle for a given database file, for uphys_buf_append
38 * operations. We only use buf_append for one file at a time, so only try to
39 * cache a single file handle, since that's all we should need. */
40 static struct buf_fdcache {
45 static char pbuffer[1024];
47 static int uphys_buf_flush(struct ubik_dbase *adbase, afs_int32 afid);
50 * \warning Beware, when using this function, of the header in front of most files.
53 uphys_open(struct ubik_dbase *adbase, afs_int32 afid)
59 struct fdcache *bestfd;
61 /* initialize package */
65 for (i = 0; i < MAXFDCACHE; tfd++, i++) {
66 tfd->fd = -1; /* invalid value */
67 tfd->fileID = -10000; /* invalid value */
72 /* scan file descr cache */
73 for (tfd = fdcache, i = 0; i < MAXFDCACHE; i++, tfd++) {
74 if (afid == tfd->fileID && tfd->refCount == 0) { /* don't use open fd */
75 lseek(tfd->fd, 0, 0); /* reset ptr just like open would have */
81 /* not found, open it and try to enter in cache */
82 snprintf(pbuffer, sizeof(pbuffer), "%s.DB%s%d", adbase->pathName,
83 (afid<0)?"SYS":"", (afid<0)?-afid:afid);
84 fd = open(pbuffer, O_CREAT | O_RDWR, 0600);
86 /* try opening read-only */
87 fd = open(pbuffer, O_RDONLY, 0);
92 /* enter it in the cache */
95 for (i = 0; i < MAXFDCACHE; i++, tfd++) { /* look for empty slot */
101 if (!bestfd) { /* look for reclaimable slot */
103 for (i = 0; i < MAXFDCACHE; i++, tfd++) {
104 if (tfd->refCount == 0) {
110 if (bestfd) { /* found a usable slot */
115 tfd->refCount = 1; /* us */
119 /* finally, we're done */
124 * \brief Close the file, maintaining ref count in cache structure.
135 for (i = 0; i < MAXFDCACHE; i++, tfd++) {
136 if (tfd->fd == afd) {
137 if (tfd->fileID != -10000) {
141 if (tfd->refCount > 0) {
143 if (tfd->refCount == 0) {
158 uphys_stat(struct ubik_dbase *adbase, afs_int32 afid, struct ubik_stat *astat)
164 fd = uphys_open(adbase, afid);
167 code = fstat(fd, &tstat);
172 code = tstat.st_size - HDRSIZE;
181 uphys_read(struct ubik_dbase *adbase, afs_int32 afile,
182 void *abuffer, afs_int32 apos, afs_int32 alength)
187 fd = uphys_open(adbase, afile);
190 code = lseek(fd, apos + HDRSIZE, 0);
195 code = read(fd, abuffer, alength);
201 uphys_write(struct ubik_dbase *adbase, afs_int32 afile,
202 void *abuffer, afs_int32 apos, afs_int32 alength)
208 fd = uphys_open(adbase, afile);
211 code = lseek(fd, apos + HDRSIZE, 0);
216 length = write(fd, abuffer, alength);
217 code = uphys_close(fd);
225 uphys_truncate(struct ubik_dbase *adbase, afs_int32 afile,
230 /* Just in case there's memory-buffered data for this file, flush it before
232 if (uphys_buf_flush(adbase, afile) < 0) {
236 fd = uphys_open(adbase, afile);
239 code = ftruncate(fd, asize + HDRSIZE);
245 * \brief Get number of dbase files.
247 * \todo Really should scan dir for data.
250 uphys_getnfiles(struct ubik_dbase *adbase)
252 /* really should scan dir for data */
257 * \brief Get database label, with \p aversion in host order.
260 uphys_getlabel(struct ubik_dbase *adbase, afs_int32 afile,
261 struct ubik_version *aversion)
263 struct ubik_hdr thdr;
266 fd = uphys_open(adbase, afile);
269 code = read(fd, &thdr, sizeof(thdr));
270 if (code != sizeof(thdr)) {
274 aversion->epoch = ntohl(thdr.version.epoch);
275 aversion->counter = ntohl(thdr.version.counter);
281 * \brief Label database, with \p aversion in host order.
284 uphys_setlabel(struct ubik_dbase *adbase, afs_int32 afile,
285 struct ubik_version *aversion)
287 struct ubik_hdr thdr;
290 fd = uphys_open(adbase, afile);
294 memset(&thdr, 0, sizeof(thdr));
296 thdr.version.epoch = htonl(aversion->epoch);
297 thdr.version.counter = htonl(aversion->counter);
298 thdr.magic = htonl(UBIK_MAGIC);
299 thdr.size = htons(HDRSIZE);
300 code = write(fd, &thdr, sizeof(thdr));
301 fsync(fd); /* preserve over crash */
303 if (code != sizeof(thdr)) {
310 uphys_sync(struct ubik_dbase *adbase, afs_int32 afile)
314 /* Flush any in-memory data, so we can sync it. */
315 if (uphys_buf_flush(adbase, afile) < 0) {
319 fd = uphys_open(adbase, afile);
326 uphys_invalidate(struct ubik_dbase *adbase, afs_int32 afid)
331 /* scan file descr cache */
332 for (tfd = fdcache, i = 0; i < MAXFDCACHE; i++, tfd++) {
333 if (afid == tfd->fileID) {
334 tfd->fileID = -10000;
335 if (tfd->fd >= 0 && tfd->refCount == 0) {
345 uphys_buf_append_open(struct ubik_dbase *adbase, afs_int32 afid)
347 /* If we have a cached handle open for this file, just return it. */
348 if (buf_fdcache.stream && buf_fdcache.fileID == afid) {
349 return buf_fdcache.stream;
352 /* Otherwise, close the existing handle, and open a new handle for the
355 if (buf_fdcache.stream) {
356 fclose(buf_fdcache.stream);
359 snprintf(pbuffer, sizeof(pbuffer), "%s.DB%s%d", adbase->pathName,
360 (afid<0)?"SYS":"", (afid<0)?-afid:afid);
361 buf_fdcache.stream = fopen(pbuffer, "a");
362 buf_fdcache.fileID = afid;
363 return buf_fdcache.stream;
367 uphys_buf_flush(struct ubik_dbase *adbase, afs_int32 afid)
369 if (buf_fdcache.stream && buf_fdcache.fileID == afid) {
370 int code = fflush(buf_fdcache.stream);
378 /* Append the given data to the given database file, allowing the data to be
379 * buffered in memory. */
381 uphys_buf_append(struct ubik_dbase *adbase, afs_int32 afid, void *adata,
387 stream = uphys_buf_append_open(adbase, afid);
392 code = fwrite(adata, alength, 1, stream);