-/**/
+/*
+ * cdb, cdb-wr - Tcl bindings for tinycdb and a journalling write extension
+ * Copyright 2006 Ian Jackson
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
#include "chiark_tcl_cdb.h"
+#define KEYLEN_MAX (INT_MAX/2)
+
#define ftello ftell
#define fseeko fseek
char *buf, *sfx;
} Pathbuf;
-#define MAX_SUFFIX 4
+#define MAX_SUFFIX 5
static void pathbuf_init(Pathbuf *pb, const char *pathb) {
- int l= strlen(pathb);
- pb->buf= TALLOC(l + 4);
+ size_t l= strlen(pathb);
+ assert(l < INT_MAX);
+ pb->buf= TALLOC(l + MAX_SUFFIX + 1);
memcpy(pb->buf, pathb, l);
pb->sfx= pb->buf + l;
- *pb->sfx++= '.';
}
static const char *pathbuf_sfx(Pathbuf *pb, const char *suffix) {
assert(strlen(suffix) <= MAX_SUFFIX);
int ix, autocompact;
int cdb_fd, lock_fd;
struct cdb cdb; /* valid iff cdb_fd >= 0 */
- FILE *logfile;
+ FILE *logfile; /* may be 0; if so, is broken */
HashTable logincore;
Pathbuf pbsome, pbother;
off_t mainsz;
}
pathbuf_free(&rw->pbsome); pathbuf_free(&rw->pbother);
- TFREE(rw);
return rc;
}
-static void destroy_cdbrw_idtabcb(Tcl_Interp *ip, void *rw) { rw_close(0,rw); }
+static void destroy_cdbrw_idtabcb(Tcl_Interp *ip, void *rw_v) {
+ rw_close(0,rw_v);
+ TFREE(rw_v);
+}
const IdDataSpec cdbtcl_rwdatabases= {
"cdb-rwdb", "cdb-openrwdatabases-table", destroy_cdbrw_idtabcb
};
/* Remove r where umask would remove w;
* eg umask intending 0664 here gives 0660 */
- *lockfd_r= open(pathbuf_sfx(pb,".lock"), O_RDONLY|O_CREAT, lockmode);
+ *lockfd_r= open(pathbuf_sfx(pb,".lock"), O_RDWR|O_CREAT, lockmode);
if (*lockfd_r < 0)
return cht_posixerr(ip, errno, "could not open/create lockfile");
*p= 0;
errno=0; ul= strtoul(numbuf, &ep, 10);
- if (*ep || errno || ul >= INT_MAX/2) return -2;
+ if (*ep || errno || ul >= KEYLEN_MAX) return -2;
*num_r= ul;
return 0;
}
int c, rc, r;
c= getc(f);
- if (c==EOF) { if (feof(f)) return -1; return -2; }
+ if (c==EOF) { return feof(f) ? -1 : -2; }
if (c=='\n') return -3;
if (c!='+') return -2;
r= fread(htv_fillptr(val), 1,vallen, f);
if (r!=vallen) goto x2_free_keyval;
+ c= getc(f); if (c!='\n') goto x2_free_keyval;
+
rc= omitfn ? omitfn(val, ctx) : TCL_OK;
if (rc) { assert(rc>0); TFREE(val); }
else updatefn(ht, key, val);
static int writerecord(FILE *f, const char *key, const HashValue *val) {
int r;
- r= fprintf(f, "+%d,%d:%s->", strlen(key), val->len, key);
+ r= fprintf(f, "+%d,%d:%s->", (int)strlen(key), val->len, key);
if (r<0) return -1;
r= fwrite(val->data, 1, val->len, f);
if (r != val->len) return -1;
+ r= putc('\n', f);
+ if (r==EOF) return -1;
+
return 0;
}
int cht_do_cdbwr_create_empty(ClientData cd, Tcl_Interp *ip,
const char *pathb) {
- static const char *const toremoves[]= {
- ".main", ".cdb", ".log", ".tmp", 0
- };
+ static const char *const toremoves[]= { ".cdb", ".jrn", ".tmp", 0 };
- Pathbuf pb;
- int lock_fd=-1, fd=-1, rc, r;
+ Pathbuf pb, pbmain;
+ int lock_fd=-1, rc, r;
+ FILE *f= 0;
const char *const *toremove;
+ struct stat stab;
pathbuf_init(&pb, pathb);
+ pathbuf_init(&pbmain, pathb);
+
rc= acquire_lock(ip, &pb, &lock_fd); if (rc) goto x_rc;
-
- fd= open(pathbuf_sfx(&pb, ".main"), O_RDWR|O_CREAT|O_EXCL, 0666);
- if (fd <= 0) PE("create new database file");
+
+ r= lstat(pathbuf_sfx(&pbmain, ".main"), &stab);
+ if (!r) { rc= cht_staticerr(ip, "database already exists during creation",
+ "CDB ALREADY-EXISTS"); goto x_rc; }
+ if (errno != ENOENT) PE("check for existing database .main during creation");
for (toremove=toremoves; *toremove; toremove++) {
- r= remove(*toremove);
+ r= remove(pathbuf_sfx(&pb, *toremove));
if (r && errno != ENOENT)
PE("delete possible spurious file during creation");
}
+ f= fopen(pathbuf_sfx(&pb, ".tmp"), "w");
+ if (!f) PE("create new database .tmp");
+ r= putc('\n', f); if (r==EOF) PE("write sentinel to new database .tmp");
+ r= fclose(f); f=0; if (r) PE("close new database .tmp during creation");
+
+ r= rename(pb.buf, pbmain.buf);
+ if (r) PE("install new database .tmp as .main (finalising creation)");
+
rc= TCL_OK;
x_rc:
- maybe_close(fd);
+ if (f) fclose(f);
maybe_close(lock_fd);
pathbuf_free(&pb);
+ pathbuf_free(&pbmain);
return rc;
}
off_t logrecstart, logjunkpos;
rw= TALLOC(sizeof(*rw));
+ rw->ix= -1;
ht_setup(&rw->logincore);
cht_scriptinv_init(&rw->on_info);
cht_scriptinv_init(&rw->on_lexminval);
pathbuf_init(&rw->pbother, pathb);
rw->autocompact= 1;
- if (on_lexminval) {
- rc= cht_scriptinv_set(&rw->on_lexminval, ip, on_lexminval, 0);
- if (rc) goto x_rc;
- } else {
- rw->on_lexminval.llength= 0;
- }
+ rc= cht_scriptinv_set(&rw->on_info, ip, on_info, 0);
+ if (rc) goto x_rc;
+
+ rc= cht_scriptinv_set(&rw->on_lexminval, ip, on_lexminval, 0);
+ if (rc) goto x_rc;
mainfd= open(pathbuf_sfx(&rw->pbsome,".main"), O_RDONLY);
if (mainfd<0) PE("open existing database file .main");
if (rw->cdb_fd >=0) {
rc= cdbinit(ip, rw); if (rc) goto x_rc;
} else if (errno == ENOENT) {
- if (rw->mainsz) {
- rc= cht_staticerr(ip, ".cdb does not exist but .main is nonempty -"
+ if (rw->mainsz > 1) {
+ rc= cht_staticerr(ip, ".cdb does not exist but .main is >1byte -"
" .cdb must have been accidentally deleted!",
"CDB CDBMISSING");
goto x_rc;
PE("open .cdb");
}
- rw->logfile= fopen(pathbuf_sfx(&rw->pbsome,".log"), "r+");
+ rw->logfile= fopen(pathbuf_sfx(&rw->pbsome,".jrn"), "r+");
if (!rw->logfile) {
- if (errno != ENOENT) PE("failed to open .log during open");
+ if (errno != ENOENT) PE("failed to open .jrn during open");
rw->logfile= fopen(rw->pbsome.buf, "w");
- if (!rw->logfile) PE("create .log during (clean) open");
+ if (!rw->logfile) PE("create .jrn during (clean) open");
} else { /* rw->logfile */
r= fstat(fileno(rw->logfile), &stab);
- if (r==-1) PE("fstat .log during open");
+ if (r==-1) PE("fstat .jrn during open");
rc= infocb(ip, rw, "open-dirty-start", "log=%luby",
(unsigned long)stab.st_size);
if (rc) goto x_rc;
for (;;) {
logrecstart= ftello(rw->logfile);
- if (logrecstart < 0) PE("ftello .log during (dirty) open");
+ if (logrecstart < 0) PE("ftello .jrn during (dirty) open");
r= readstorelogrecord(rw->logfile, &rw->logincore, 0,0, ht_update);
if (ferror(rw->logfile)) {
- rc= cht_posixerr(ip, errno, "error reading .log during (dirty) open");
+ rc= cht_posixerr(ip, errno, "error reading .jrn during (dirty) open");
goto x_rc;
}
if (r==-1) {
} else if (r==-2 || r==-3) {
char buf[100];
logjunkpos= ftello(rw->logfile);
- if(logjunkpos<0) PE("ftello .log during report of junk in dirty open");
+ if(logjunkpos<0) PE("ftello .jrn during report of junk in dirty open");
snprintf(buf,sizeof(buf), "CDB SYNTAX LOG %lu %lu",
(unsigned long)logjunkpos, (unsigned long)logrecstart);
Tcl_SetObjErrorCode(ip, Tcl_NewStringObj(buf,-1));
snprintf(buf,sizeof(buf),"%lu",(unsigned long)logjunkpos);
Tcl_ResetResult(ip);
- Tcl_AppendResult(ip, "syntax error (junk) in .log during"
+ Tcl_AppendResult(ip, "syntax error (junk) in .jrn during"
" (dirty) open, at file position ", buf, (char*)0);
rc= TCL_ERROR;
goto x_rc;
if (rc) goto x_rc;
r= fseeko(rw->logfile, logrecstart, SEEK_SET);
- if (r) PE("failed to fseeko .log before junk during dirty open");
+ if (r) PE("failed to fseeko .jrn before junk during dirty open");
r= ftruncate(fileno(rw->logfile), logrecstart);
- if (r) PE("ftruncate .log to chop junk during dirty open");
+ if (r) PE("ftruncate .jrn to chop junk during dirty open");
} else {
assert(!r);
}
x_rc:
rw_close(0,rw);
+ TFREE(rw);
maybe_close(mainfd);
return rc;
}
struct ht_forall_ctx {
struct cdb_make cdbm;
FILE *mainfile;
- int lexminvall;
long *reccount;
- const char *lexminval;
+ int lexminvall;
+ const char *lexminval; /* may be invalid if lexminvall <= 0 */
};
/*---------- helper functions ----------*/
static int expiredp(const HashValue *val, struct ht_forall_ctx *a) {
int r, l;
- if (!val->len) return 0;
+ if (!val->len || a->lexminvall<=0) return 0;
l= val->len < a->lexminvall ? val->len : a->lexminvall;
r= memcmp(val->data, a->lexminval, l);
if (r>0) return 0;
long *reccount_r) {
/* creates new .cdb and .main
* closes logfile
- * leaves .log with old data
+ * leaves .jrn with old data
* leaves cdb fd open onto old db
* leaves logincore full of crap
*/
a.reccount= reccount_r;
r= fclose(rw->logfile);
+ rw->logfile= 0;
if (r) { rc= cht_posixerr(ip, errno, "probable data loss! failed to fclose"
" logfile during compact"); goto x_rc; }
- rw->logfile= 0;
rc= infocb(ip, rw, "compact-start", "log=%luby main=%luby",
logsz, (unsigned long)rw->mainsz);
if (rc) goto x_rc;
- if (rw->on_lexminval.llength) {
+ if (cht_scriptinv_interp(&rw->on_lexminval)) {
rc= cht_scriptinv_invoke_fg(&rw->on_lexminval, 0,0);
if (rc) goto x_rc;
rc= ht_forall(&rw->logincore, delete_ifexpired, &a);
} else {
- a.lexminval= "";
+ a.lexminvall= 0;
}
/* merge unsuperseded records from main into hash table */
expiredp, &a,
ht_maybeupdate);
if (ferror(a.mainfile)) { rc= cht_posixerr(ip, errno, "error reading"
- " .main during compact"); goto x_rc;
- }
+ " .main during compact"); goto x_rc; }
if (r==-3) {
break;
} else if (r==-1 || r==-2) {
errpos= ftello(a.mainfile);
if (errpos<0) PE("ftello .main during report of syntax error");
- snprintf(buf,sizeof(buf), "CDB SYNTAX MAIN %lu", (unsigned long)errpos);
+ snprintf(buf,sizeof(buf), "CDB %s MAIN %lu",
+ r==-1 ? "TRUNCATED" : "SYNTAX", (unsigned long)errpos);
Tcl_SetObjErrorCode(ip, Tcl_NewStringObj(buf,-1));
snprintf(buf,sizeof(buf), "%lu", (unsigned long)errpos);
Tcl_ResetResult(ip);
- Tcl_AppendResult(ip, "syntax error in .main during"
- " compact, at file position ", buf, (char*)0);
+ Tcl_AppendResult(ip,
+ r==-1 ? "unexpected eof (truncated file)"
+ " in .main during compact, at file position "
+ : "syntax error"
+ " in .main during compact, at file position ",
+ buf, (char*)0);
rc= TCL_ERROR;
goto x_rc;
} else {
if (!a.mainfile) PE("create .tmp for new main during compact");
r= ht_forall(&rw->logincore, addto_main, &a);
- if (r) { rc= cht_posixerr(ip, r, "error writing to new .main"
+ if (r) { rc= cht_posixerr(ip, errno, "error writing to new .main"
" during compact"); goto x_rc; }
+
+ r= putc('\n', a.mainfile);
+ if (r==EOF) PE("write trailing \n to main during compact");
r= fflush(a.mainfile); if (r) PE("fflush new main during compact");
r= fdatasync(fileno(a.mainfile));
/* done! */
- rc= infocb(ip, rw, "compact-end", "main=%luby nrecs=%l",
+ rc= infocb(ip, rw, "compact-end", "main=%luby nrecs=%ld",
(unsigned long)rw->mainsz, *a.reccount);
if (rc) goto x_rc;
rc= compact_core(ip, rw, logsz, reccount_r); if (rc) goto x_rc;
- r= remove(pathbuf_sfx(&rw->pbsome,".log"));
- if (r) PE("remove .log (during tidy close)");
+ r= remove(pathbuf_sfx(&rw->pbsome,".jrn"));
+ if (r) PE("remove .jrn (during tidy close)");
return TCL_OK;
else rc= TCL_OK;
if (!rc) {
- if (!rw->logfile) {
+ if (rw->logfile) {
logsz= ftello(rw->logfile);
if (logsz < 0)
rc= cht_posixerr(ip, errno, "ftell logfile during close info");
rc= infocb(ip, rw, "close", "main=%luby log=%luby",
rw->mainsz, logsz);
} else if (reccount>=0) {
- rc= infocb(ip, rw, "close", "main=%luby nrecs=%l", rw->mainsz, reccount);
+ rc= infocb(ip, rw, "close", "main=%luby nrecs=%ld",
+ rw->mainsz, reccount);
} else {
rc= infocb(ip, rw, "close", "main=%luby", rw->mainsz);
}
if (rc_close) rc= rc_close;
cht_tabledataid_disposing(ip, rw_v, &cdbtcl_rwdatabases);
+ TFREE(rw);
return rc;
}
int rc, r;
logsz= ftello(rw->logfile);
- if (logsz < 0) return cht_posixerr(ip, errno, "ftell .log"
+ if (logsz < 0) return cht_posixerr(ip, errno, "ftell .jrn"
" during compact check or force");
- if (!force && logsz < rw->mainsz / 10 + 1000) return TCL_OK;
+ if (!force && logsz < rw->mainsz / 3 + 1000) return TCL_OK;
+ /* Test case: ^^^ testing best value for this
+ * main=9690434by nrecs=122803 read all in one go
+ * no autocompact, : 6.96user 0.68system 0:08.93elapsed
+ * auto, mulitplier 2: 7.10user 0.79system 0:09.54elapsed
+ * auto, unity: 7.80user 0.98system 0:11.84elapsed
+ * auto, divisor 2: 8.23user 1.05system 0:13.30elapsed
+ * auto, divisor 3: 8.55user 1.12system 0:12.88elapsed
+ * auto, divisor 5: 9.95user 1.43system 0:15.72elapsed
+ */
rc= compact_core(ip, rw, logsz, &reccount); if (rc) goto x_rc;
rc= cdbinit(ip, rw); if (rc) goto x_rc;
- rw->logfile= fopen(pathbuf_sfx(&rw->pbsome,".log"), "w");
- if (!rw->logfile) PE("reopen .log after compact");
+ rw->logfile= fopen(pathbuf_sfx(&rw->pbsome,".jrn"), "w");
+ if (!rw->logfile) PE("reopen .jrn after compact");
- r= fsync(fileno(rw->logfile)); if (r) PE("fsync .log after compact reopen");
+ r= fsync(fileno(rw->logfile)); if (r) PE("fsync .jrn after compact reopen");
return TCL_OK;
static int update(Tcl_Interp *ip, Rw *rw, const char *key,
const Byte *data, int dlen) {
HashValue *val;
+ const char *failed;
int rc, r;
+ off_t recstart;
+
+ if (strlen(key) >= KEYLEN_MAX)
+ return cht_staticerr(ip, "key too long", "CDB KEYOVERFLOW");
if (!rw->logfile) return cht_staticerr
- (ip, "previous compact failed; cdbwr must be closed and reopened "
- "before any further updates", "CDB BROKEN");
+ (ip, "failure during previous compact or error recovery;"
+ " cdbwr must be closed and reopened before any further updates",
+ "CDB BROKEN");
+ recstart= ftello(rw->logfile);
+ if (recstart < 0)
+ return cht_posixerr(ip, errno, "failed to ftello .jrn during update");
+
val= htv_prep(dlen); assert(val);
memcpy(htv_fillptr(val), data, dlen);
if (r) PE("write update to logfile");
ht_update(&rw->logincore, key, val);
+
+ if (!rw->autocompact) return TCL_OK;
return compact_keepopen(ip, rw, 0);
x_rc:
TFREE(val);
+ assert(rc);
+
+ /* Now, we have to try to sort out the journal so that it's
+ * truncated and positioned to where this abortively-written record
+ * started, with no buffered output and the error indicator clear.
+ *
+ * There seems to be no portable way to ensure the buffered unwritten
+ * output is discarded, so we close and reopen the stream.
+ */
+ fclose(rw->logfile);
+
+ rw->logfile= fopen(pathbuf_sfx(&rw->pbsome,".jrn"), "r+");
+ if (!rw->logfile) { failed= "fopen"; goto reset_fail; }
+
+ r= ftruncate(fileno(rw->logfile), recstart);
+ if (r) { failed= "ftruncate"; goto reset_fail; }
+
+ r= fseeko(rw->logfile, recstart, SEEK_SET);
+ if (r) { failed= "fseeko"; goto reset_fail; }
+
+ return rc;
+
+ reset_fail:
+ Tcl_AppendResult(ip, " (additionally, ", failed, " failed"
+ " in error recovery: ", strerror(errno), ")", (char*)0);
+ if (rw->logfile) { fclose(rw->logfile); rw->logfile= 0; }
+
return rc;
}
return cht_cdb_donesomelookup(ip, rw_v, def, result, data, dlen,
cht_cdb_storeanswer_hb);
}
-
-int cht_do_cdbtoplevel_cdb_wr(ClientData cd, Tcl_Interp *ip,
- const Cdbwr_SubCommand* subcmd,
- int objc, Tcl_Obj *const *objv) {
- return subcmd->func((void*)subcmd,ip,objc,objv);
-}