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Diffstat (limited to 'debian/htdig/htdig-3.2.0b6/db/log_get.c')
-rw-r--r--debian/htdig/htdig-3.2.0b6/db/log_get.c355
1 files changed, 355 insertions, 0 deletions
diff --git a/debian/htdig/htdig-3.2.0b6/db/log_get.c b/debian/htdig/htdig-3.2.0b6/db/log_get.c
new file mode 100644
index 00000000..1fcb26e1
--- /dev/null
+++ b/debian/htdig/htdig-3.2.0b6/db/log_get.c
@@ -0,0 +1,355 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996, 1997, 1998, 1999
+ * Sleepycat Software. All rights reserved.
+ */
+#include "db_config.h"
+
+#ifndef lint
+static const char sccsid[] = "@(#)CDB_log_get.c 11.4 (Sleepycat) 9/16/99";
+#endif /* not lint */
+
+#ifndef NO_SYSTEM_INCLUDES
+#include <sys/types.h>
+
+#include <errno.h>
+#include <string.h>
+
+#ifndef _MSC_VER /* _WIN32 */
+#include <unistd.h>
+#endif
+
+#endif /* !NO_SYSTEM_INCLUDES */
+
+#include "db_int.h"
+#include "db_page.h"
+#include "log.h"
+#include "hash.h"
+
+/*
+ * CDB_log_get --
+ * Get a log record.
+ */
+int
+CDB_log_get(dbenv, alsn, dbt, flags)
+ DB_ENV *dbenv;
+ DB_LSN *alsn;
+ DBT *dbt;
+ u_int32_t flags;
+{
+ DB_LOG *dblp;
+ int ret;
+
+ PANIC_CHECK(dbenv);
+ ENV_REQUIRES_CONFIG(dbenv, dbenv->lg_handle, DB_INIT_LOG);
+
+ /* Validate arguments. */
+ if (flags != DB_CHECKPOINT && flags != DB_CURRENT &&
+ flags != DB_FIRST && flags != DB_LAST &&
+ flags != DB_NEXT && flags != DB_PREV && flags != DB_SET)
+ return (CDB___db_ferr(dbenv, "CDB_log_get", 1));
+
+ if (F_ISSET(dbenv, DB_ENV_THREAD)) {
+ if (flags == DB_NEXT || flags == DB_PREV || flags == DB_CURRENT)
+ return (CDB___db_ferr(dbenv, "CDB_log_get", 1));
+ if (!F_ISSET(dbt,
+ DB_DBT_MALLOC | DB_DBT_REALLOC | DB_DBT_USERMEM))
+ return (CDB___db_ferr(dbenv, "threaded data", 1));
+ }
+
+ dblp = dbenv->lg_handle;
+ R_LOCK(dbenv, &dblp->reginfo);
+
+ /*
+ * If we get one of the log's header records, repeat the operation.
+ * This assumes that applications don't ever request the log header
+ * records by LSN, but that seems reasonable to me.
+ */
+ ret = CDB___log_get(dblp, alsn, dbt, flags, 0);
+ if (ret == 0 && alsn->offset == 0) {
+ switch (flags) {
+ case DB_FIRST:
+ flags = DB_NEXT;
+ break;
+ case DB_LAST:
+ flags = DB_PREV;
+ break;
+ }
+ ret = CDB___log_get(dblp, alsn, dbt, flags, 0);
+ }
+
+ R_UNLOCK(dbenv, &dblp->reginfo);
+
+ return (ret);
+}
+
+/*
+ * CDB___log_get --
+ * Get a log record; internal version.
+ *
+ * PUBLIC: int CDB___log_get __P((DB_LOG *, DB_LSN *, DBT *, u_int32_t, int));
+ */
+int
+CDB___log_get(dblp, alsn, dbt, flags, silent)
+ DB_LOG *dblp;
+ DB_LSN *alsn;
+ DBT *dbt;
+ u_int32_t flags;
+ int silent;
+{
+ DB_LSN nlsn;
+ HDR hdr;
+ LOG *lp;
+ size_t len;
+ ssize_t nr;
+ int cnt, ret;
+ char *np, *tbuf;
+ const char *fail;
+ void *shortp;
+ u_int8_t *p;
+
+ lp = dblp->reginfo.primary;
+ fail = np = tbuf = NULL;
+
+ nlsn = dblp->c_lsn;
+ switch (flags) {
+ case DB_CHECKPOINT:
+ nlsn = lp->chkpt_lsn;
+ if (IS_ZERO_LSN(nlsn)) {
+ ret = ENOENT;
+ goto err2;
+ }
+ break;
+ case DB_NEXT: /* Next log record. */
+ if (!IS_ZERO_LSN(nlsn)) {
+ /* Increment the cursor by the cursor record size. */
+ nlsn.offset += dblp->c_len;
+ break;
+ }
+ /* FALLTHROUGH */
+ case DB_FIRST: /* Find the first log record. */
+ /* Find the first log file. */
+ if ((ret = CDB___log_find(dblp, 1, &cnt)) != 0)
+ goto err2;
+
+ /*
+ * We may have only entered records in the buffer, and not
+ * yet written a log file. If no log files were found and
+ * there's anything in the buffer, it belongs to file 1.
+ */
+ if (cnt == 0)
+ cnt = 1;
+
+ nlsn.file = cnt;
+ nlsn.offset = 0;
+ break;
+ case DB_CURRENT: /* Current log record. */
+ break;
+ case DB_PREV: /* Previous log record. */
+ if (!IS_ZERO_LSN(nlsn)) {
+ /* If at start-of-file, move to the previous file. */
+ if (nlsn.offset == 0) {
+ if (nlsn.file == 1 ||
+ CDB___log_valid(dblp, nlsn.file - 1, 0) != 0)
+ return (DB_NOTFOUND);
+
+ --nlsn.file;
+ nlsn.offset = dblp->c_off;
+ } else
+ nlsn.offset = dblp->c_off;
+ break;
+ }
+ /* FALLTHROUGH */
+ case DB_LAST: /* Last log record. */
+ nlsn.file = lp->lsn.file;
+ nlsn.offset = lp->lsn.offset - lp->len;
+ break;
+ case DB_SET: /* Set log record. */
+ nlsn = *alsn;
+ break;
+ }
+
+ if (0) { /* Move to the next file. */
+next_file: ++nlsn.file;
+ nlsn.offset = 0;
+ }
+
+ /* Return 1 if the request is past the end of the log. */
+ if (nlsn.file > lp->lsn.file ||
+ (nlsn.file == lp->lsn.file && nlsn.offset >= lp->lsn.offset))
+ return (DB_NOTFOUND);
+
+ /* If we've switched files, discard the current file handle. */
+ if (dblp->c_lsn.file != nlsn.file &&
+ F_ISSET(&dblp->c_fh, DB_FH_VALID))
+ (void)CDB___os_closehandle(&dblp->c_fh);
+
+ /* If the entire record is in the in-memory buffer, copy it out. */
+ if (nlsn.file == lp->lsn.file && nlsn.offset >= lp->w_off) {
+ /* Copy the header. */
+ p = dblp->bufp + (nlsn.offset - lp->w_off);
+ memcpy(&hdr, p, sizeof(HDR));
+
+ /* Copy the record. */
+ len = hdr.len - sizeof(HDR);
+ if ((ret = CDB___db_retcopy(NULL, dbt, p + sizeof(HDR),
+ len, &dblp->c_dbt.data, &dblp->c_dbt.ulen)) != 0)
+ goto err1;
+ goto cksum;
+ }
+
+ /* Acquire a file descriptor. */
+ if (!F_ISSET(&dblp->c_fh, DB_FH_VALID)) {
+ if ((ret = CDB___log_name(dblp, nlsn.file,
+ &np, &dblp->c_fh, DB_OSO_RDONLY | DB_OSO_SEQ)) != 0) {
+ fail = np;
+ goto err1;
+ }
+ CDB___os_freestr(np);
+ np = NULL;
+ }
+
+ /*
+ * Seek to the header offset and read the header. Because the file
+ * may be pre-allocated, we have to make sure that we're not reading
+ * past the information in the start of the in-memory buffer.
+ */
+ if ((ret = CDB___os_seek(
+ &dblp->c_fh, 0, 0, nlsn.offset, 0, DB_OS_SEEK_SET)) != 0) {
+ fail = "seek";
+ goto err1;
+ }
+ if (nlsn.file == lp->lsn.file && nlsn.offset + sizeof(HDR) > lp->w_off)
+ nr = lp->w_off - nlsn.offset;
+ else
+ nr = sizeof(HDR);
+ if ((ret = CDB___os_read(&dblp->c_fh, &hdr, nr, &nr)) != 0) {
+ fail = "read";
+ goto err1;
+ }
+ if (nr == sizeof(HDR))
+ shortp = NULL;
+ else {
+ /* If read returns EOF, try the next file. */
+ if (nr == 0) {
+ if (flags != DB_NEXT || nlsn.file == lp->lsn.file)
+ goto corrupt;
+ goto next_file;
+ }
+
+ /*
+ * If read returns a short count the rest of the record has
+ * to be in the in-memory buffer.
+ */
+ if (lp->b_off < sizeof(HDR) - nr)
+ goto corrupt;
+
+ /* Get the rest of the header from the in-memory buffer. */
+ memcpy((u_int8_t *)&hdr + nr, dblp->bufp, sizeof(HDR) - nr);
+ shortp = dblp->bufp + (sizeof(HDR) - nr);
+ }
+
+ /*
+ * Check for buffers of 0's, that's what we usually see during recovery,
+ * although it's certainly not something on which we can depend. Check
+ * for impossibly large records. The malloc should fail later, but we
+ * have customers that run mallocs that handle allocation failure as a
+ * fatal error.
+ */
+ if (hdr.len == 0)
+ goto next_file;
+ if (hdr.len <= sizeof(HDR) || hdr.len > lp->persist.lg_max)
+ goto corrupt;
+ len = hdr.len - sizeof(HDR);
+
+ /* If we've already moved to the in-memory buffer, fill from there. */
+ if (shortp != NULL) {
+ if (lp->b_off < ((u_int8_t *)shortp - dblp->bufp) + len)
+ goto corrupt;
+ if ((ret = CDB___db_retcopy(NULL, dbt, shortp, len,
+ &dblp->c_dbt.data, &dblp->c_dbt.ulen)) != 0)
+ goto err1;
+ goto cksum;
+ }
+
+ /*
+ * Allocate temporary memory to hold the record.
+ *
+ * XXX
+ * We're calling malloc(3) with a region locked. This isn't
+ * a good idea.
+ */
+ if ((ret = CDB___os_malloc(len, NULL, &tbuf)) != 0)
+ goto err1;
+
+ /*
+ * Read the record into the buffer. If read returns a short count,
+ * there was an error or the rest of the record is in the in-memory
+ * buffer. Note, the information may be garbage if we're in recovery,
+ * so don't read past the end of the buffer's memory.
+ *
+ * Because the file may be pre-allocated, we have to make sure that
+ * we're not reading past the information in the start of the in-memory
+ * buffer.
+ */
+ if (nlsn.file == lp->lsn.file &&
+ nlsn.offset + sizeof(HDR) + len > lp->w_off)
+ nr = lp->w_off - (nlsn.offset + sizeof(HDR));
+ else
+ nr = len;
+ if ((ret = CDB___os_read(&dblp->c_fh, tbuf, nr, &nr)) != 0) {
+ fail = "read";
+ goto err1;
+ }
+ if (len - nr > lp->buffer_size)
+ goto corrupt;
+ if (nr != (ssize_t)len) {
+ if (lp->b_off < len - nr)
+ goto corrupt;
+
+ /* Get the rest of the record from the in-memory buffer. */
+ memcpy((u_int8_t *)tbuf + nr, dblp->bufp, len - nr);
+ }
+
+ /* Copy the record into the user's DBT. */
+ if ((ret = CDB___db_retcopy(NULL, dbt, tbuf, len,
+ &dblp->c_dbt.data, &dblp->c_dbt.ulen)) != 0)
+ goto err1;
+ CDB___os_free(tbuf, 0);
+ tbuf = NULL;
+
+cksum: if (hdr.cksum != CDB___ham_func4(dbt->data, dbt->size)) {
+ if (!silent)
+ CDB___db_err(dblp->dbenv, "CDB_log_get: checksum mismatch");
+ goto corrupt;
+ }
+
+ /* Update the cursor and the return lsn. */
+ dblp->c_off = hdr.prev;
+ dblp->c_len = hdr.len;
+ dblp->c_lsn = *alsn = nlsn;
+
+ return (0);
+
+corrupt:/*
+ * This is the catchall -- for some reason we didn't find enough
+ * information or it wasn't reasonable information, and it wasn't
+ * because a system call failed.
+ */
+ ret = EIO;
+ fail = "read";
+
+err1: if (!silent) {
+ if (fail == NULL)
+ CDB___db_err(dblp->dbenv, "CDB_log_get: %s", CDB_db_strerror(ret));
+ else
+ CDB___db_err(dblp->dbenv,
+ "CDB_log_get: %s: %s", fail, CDB_db_strerror(ret));
+ }
+err2: if (np != NULL)
+ CDB___os_freestr(np);
+ if (tbuf != NULL)
+ CDB___os_free(tbuf, 0);
+ return (ret);
+}