2 * cdb, cdb-wr - Tcl bindings for tinycdb and a journalling write extension
3 * Copyright 2006 Ian Jackson
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation; either version 2 of the
8 * License, or (at your option) any later version.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this library; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
21 #include "chiark_tcl_cdb.h"
26 /*---------- Forward declarations ----------*/
30 /*---------- Useful routines ----------*/
32 static void maybe_close(int fd) {
36 /*==================== Subsystems and subtypes ====================*/
38 /*---------- Pathbuf ----------*/
40 typedef struct Pathbuf {
46 static void pathbuf_init(Pathbuf *pb, const char *pathb) {
48 pb->buf= TALLOC(l + MAX_SUFFIX + 1);
49 memcpy(pb->buf, pathb, l);
52 static const char *pathbuf_sfx(Pathbuf *pb, const char *suffix) {
53 assert(strlen(suffix) <= MAX_SUFFIX);
54 strcpy(pb->sfx, suffix);
57 static void pathbuf_free(Pathbuf *pb) {
62 /*---------- Our hash table ----------*/
64 typedef struct HashTable {
66 Byte padding[128]; /* allow for expansion by Tcl, urgh */
70 typedef struct HashValue {
75 static HashValue *htv_prep(int len) {
77 hd= TALLOC((hd->data - (Byte*)hd) + len);
81 static Byte *htv_fillptr(HashValue *hd) {
85 static void ht_setup(HashTable *ht) {
86 Tcl_InitHashTable(&ht->t, TCL_STRING_KEYS);
88 static void ht_update(HashTable *ht, const char *key, HashValue *val_eat) {
92 he= Tcl_CreateHashEntry(&ht->t, (char*)key, &new);
93 if (!new) TFREE(Tcl_GetHashValue(he));
94 Tcl_SetHashValue(he, val_eat);
95 /* eats the value since the data structure owns the memory */
97 static void ht_maybeupdate(HashTable *ht, const char *key,
99 /* like ht_update except does not overwrite existing values */
103 he= Tcl_CreateHashEntry(&ht->t, (char*)key, &new);
104 if (!new) { TFREE(val_eat); return; }
105 Tcl_SetHashValue(he, val_eat);
108 static const HashValue *ht_lookup(HashTable *ht, const char *key) {
111 he= Tcl_FindHashEntry(&ht->t, key);
114 return Tcl_GetHashValue(he);
117 static int ht_forall(HashTable *ht,
118 int (*fn)(const char *key, HashValue *val,
119 struct ht_forall_ctx *ctx),
120 struct ht_forall_ctx *ctx) {
121 /* Returns first positive value returned by any call to fn, or 0. */
128 for (he= Tcl_FirstHashEntry(&ht->t, &sp);
130 he= Tcl_NextHashEntry(&sp)) {
131 val= Tcl_GetHashValue(he);
132 if (!val->len) continue;
134 key= Tcl_GetHashKey(&ht->t, he);
136 r= fn(key, val, ctx);
142 static void ht_destroy(HashTable *ht) {
146 for (he= Tcl_FirstHashEntry(&ht->t, &sp);
148 he= Tcl_NextHashEntry(&sp)) {
149 /* ht_forall skips empty (deleted) entries so is no good for this */
150 TFREE(Tcl_GetHashValue(he));
152 Tcl_DeleteHashTable(&ht->t);
155 /*==================== Existential ====================*/
157 /*---------- Rw data structure ----------*/
162 struct cdb cdb; /* valid iff cdb_fd >= 0 */
165 Pathbuf pbsome, pbother;
167 ScriptToInvoke on_info, on_lexminval;
170 static int rw_close(Tcl_Interp *ip, Rw *rw) {
174 ht_destroy(&rw->logincore);
175 if (rw->cdb_fd >= 0) cdb_free(&rw->cdb);
176 maybe_close(rw->cdb_fd);
177 maybe_close(rw->lock_fd);
180 r= fclose(rw->logfile);
181 if (r && ip) { rc= cht_posixerr(ip, errno, "probable data loss! failed to"
182 " fclose logfile during untidy close"); }
185 pathbuf_free(&rw->pbsome); pathbuf_free(&rw->pbother);
189 static void destroy_cdbrw_idtabcb(Tcl_Interp *ip, void *rw_v) {
193 const IdDataSpec cdbtcl_rwdatabases= {
194 "cdb-rwdb", "cdb-openrwdatabases-table", destroy_cdbrw_idtabcb
197 /*---------- File handling ----------*/
199 static int acquire_lock(Tcl_Interp *ip, Pathbuf *pb, int *lockfd_r) {
200 /* *lockfd_r must be -1 on entry. If may be set to >=0 even
201 * on error, and must be closed by the caller. */
206 um= umask(~(mode_t)0);
209 lockmode= 0666 & ~((um & 0444)>>1);
210 /* Remove r where umask would remove w;
211 * eg umask intending 0664 here gives 0660 */
213 *lockfd_r= open(pathbuf_sfx(pb,".lock"), O_RDWR|O_CREAT, lockmode);
215 return cht_posixerr(ip, errno, "could not open/create lockfile");
218 fl.l_whence= SEEK_SET;
223 r= fcntl(*lockfd_r, F_SETLK, &fl);
225 if (errno == EACCES || errno == EAGAIN)
226 return cht_staticerr(ip, "lock held by another process", "CDB LOCKED");
227 else return cht_posixerr(ip, errno, "unexpected error from fcntl while"
234 /*---------- Log reading and writing ----------*/
236 static int readlognum(FILE *f, int delim, int *num_r) {
238 char numbuf[20], *p, *ep;
243 c= getc(f); if (c==EOF) return -2;
244 if (c == delim) break;
245 if (!isdigit((unsigned char)c)) return -2;
247 if (p == numbuf+sizeof(numbuf)) return -2;
249 if (p == numbuf) return -2;
252 errno=0; ul= strtoul(numbuf, &ep, 10);
253 if (*ep || errno || ul >= INT_MAX/2) return -2;
258 static int readstorelogrecord(FILE *f, HashTable *ht,
259 int (*omitfn)(const HashValue*,
260 struct ht_forall_ctx *ctx),
261 struct ht_forall_ctx *ctx,
262 void (*updatefn)(HashTable*, const char*,
267 * -2 corrupt or error
268 * -3 got newline indicating end
269 * >0 value from omitfn
277 if (c==EOF) { return feof(f) ? -1 : -2; }
278 if (c=='\n') return -3;
279 if (c!='+') return -2;
281 rc= readlognum(f, ',', &keylen); if (rc) return rc;
282 rc= readlognum(f, ':', &vallen); if (rc) return rc;
284 key= TALLOC(keylen+1);
285 val= htv_prep(vallen);
287 r= fread(key, 1,keylen, f);
288 if (r!=keylen) goto x2_free_keyval;
289 if (memchr(key,0,keylen)) goto x2_free_keyval;
292 c= getc(f); if (c!='-') goto x2_free_keyval;
293 c= getc(f); if (c!='>') goto x2_free_keyval;
295 r= fread(htv_fillptr(val), 1,vallen, f);
296 if (r!=vallen) goto x2_free_keyval;
298 c= getc(f); if (c!='\n') goto x2_free_keyval;
300 rc= omitfn ? omitfn(val, ctx) : TCL_OK;
301 if (rc) { assert(rc>0); TFREE(val); }
302 else updatefn(ht, key, val);
313 static int writerecord(FILE *f, const char *key, const HashValue *val) {
316 r= fprintf(f, "+%d,%d:%s->", strlen(key), val->len, key);
319 r= fwrite(val->data, 1, val->len, f);
320 if (r != val->len) return -1;
323 if (r==EOF) return -1;
328 /*---------- Creating ----------*/
330 int cht_do_cdbwr_create_empty(ClientData cd, Tcl_Interp *ip,
332 static const char *const toremoves[]= { ".cdb", ".jrn", ".tmp", 0 };
335 int lock_fd=-1, rc, r;
337 const char *const *toremove;
340 pathbuf_init(&pb, pathb);
341 pathbuf_init(&pbmain, pathb);
343 rc= acquire_lock(ip, &pb, &lock_fd); if (rc) goto x_rc;
345 r= lstat(pathbuf_sfx(&pbmain, ".main"), &stab);
346 if (!r) { rc= cht_staticerr(ip, "database already exists during creation",
347 "CDB ALREADY-EXISTS"); goto x_rc; }
348 if (errno != ENOENT) PE("check for existing database .main during creation");
350 for (toremove=toremoves; *toremove; toremove++) {
351 r= remove(pathbuf_sfx(&pb, *toremove));
352 if (r && errno != ENOENT)
353 PE("delete possible spurious file during creation");
356 f= fopen(pathbuf_sfx(&pb, ".tmp"), "w");
357 if (!f) PE("create new database .tmp");
358 r= putc('\n', f); if (r==EOF) PE("write sentinel to new database .tmp");
359 r= fclose(f); f=0; if (r) PE("close new database .tmp during creation");
361 r= rename(pb.buf, pbmain.buf);
362 if (r) PE("install new database .tmp as .main (finalising creation)");
368 maybe_close(lock_fd);
370 pathbuf_free(&pbmain);
374 /*---------- Info callbacks ----------*/
376 static int infocbv3(Tcl_Interp *ip, Rw *rw, const char *arg1,
377 const char *arg2fmt, const char *arg3, va_list al) {
381 vsnprintf(buf, sizeof(buf), arg2fmt, al);
384 aa[na++]= cht_ret_string(ip, arg1);
385 aa[na++]= cht_ret_string(ip, buf);
386 if (arg3) aa[na++]= cht_ret_string(ip, arg3);
388 return cht_scriptinv_invoke_fg(&rw->on_info, na, aa);
391 static int infocb3(Tcl_Interp *ip, Rw *rw, const char *arg1,
392 const char *arg2fmt, const char *arg3, ...) {
396 rc= infocbv3(ip,rw,arg1,arg2fmt,arg3,al);
401 static int infocb(Tcl_Interp *ip, Rw *rw, const char *arg1,
402 const char *arg2fmt, ...) {
405 va_start(al, arg2fmt);
406 rc= infocbv3(ip,rw,arg1,arg2fmt,0,al);
411 /*---------- Opening ----------*/
413 static int cdbinit(Tcl_Interp *ip, Rw *rw) {
414 /* On entry, cdb_fd >=0 but cdb is _undefined_/
415 * On exit, either cdb_fd<0 or cdb is initialised */
418 r= cdb_init(&rw->cdb, rw->cdb_fd);
420 rc= cht_posixerr(ip, errno, "failed to initialise cdb reader");
421 close(rw->cdb_fd); rw->cdb_fd= -1; return rc;
426 int cht_do_cdbwr_open(ClientData cd, Tcl_Interp *ip, const char *pathb,
427 Tcl_Obj *on_info, Tcl_Obj *on_lexminval,
429 const Cdbwr_SubCommand *subcmd= cd;
430 int r, rc, mainfd=-1;
433 off_t logrecstart, logjunkpos;
435 rw= TALLOC(sizeof(*rw));
437 ht_setup(&rw->logincore);
438 cht_scriptinv_init(&rw->on_info);
439 cht_scriptinv_init(&rw->on_lexminval);
440 rw->cdb_fd= rw->lock_fd= -1; rw->logfile= 0;
441 pathbuf_init(&rw->pbsome, pathb);
442 pathbuf_init(&rw->pbother, pathb);
445 rc= cht_scriptinv_set(&rw->on_info, ip, on_info, 0);
448 rc= cht_scriptinv_set(&rw->on_lexminval, ip, on_lexminval, 0);
451 mainfd= open(pathbuf_sfx(&rw->pbsome,".main"), O_RDONLY);
452 if (mainfd<0) PE("open existing database file .main");
453 rc= acquire_lock(ip, &rw->pbsome, &rw->lock_fd); if (rc) goto x_rc;
455 r= fstat(mainfd, &stab); if (r) PE("fstat .main");
456 rw->mainsz= stab.st_size;
458 rw->cdb_fd= open(pathbuf_sfx(&rw->pbsome,".cdb"), O_RDONLY);
459 if (rw->cdb_fd >=0) {
460 rc= cdbinit(ip, rw); if (rc) goto x_rc;
461 } else if (errno == ENOENT) {
462 if (rw->mainsz > 1) {
463 rc= cht_staticerr(ip, ".cdb does not exist but .main is >1byte -"
464 " .cdb must have been accidentally deleted!",
473 rw->logfile= fopen(pathbuf_sfx(&rw->pbsome,".jrn"), "r+");
475 if (errno != ENOENT) PE("failed to open .jrn during open");
476 rw->logfile= fopen(rw->pbsome.buf, "w");
477 if (!rw->logfile) PE("create .jrn during (clean) open");
478 } else { /* rw->logfile */
479 r= fstat(fileno(rw->logfile), &stab);
480 if (r==-1) PE("fstat .jrn during open");
481 rc= infocb(ip, rw, "open-dirty-start", "log=%luby",
482 (unsigned long)stab.st_size);
486 logrecstart= ftello(rw->logfile);
487 if (logrecstart < 0) PE("ftello .jrn during (dirty) open");
488 r= readstorelogrecord(rw->logfile, &rw->logincore, 0,0, ht_update);
489 if (ferror(rw->logfile)) {
490 rc= cht_posixerr(ip, errno, "error reading .jrn during (dirty) open");
495 } else if (r==-2 || r==-3) {
497 logjunkpos= ftello(rw->logfile);
498 if(logjunkpos<0) PE("ftello .jrn during report of junk in dirty open");
500 snprintf(buf,sizeof(buf), "CDB SYNTAX LOG %lu %lu",
501 (unsigned long)logjunkpos, (unsigned long)logrecstart);
503 if (!(subcmd->flags & RWSCF_OKJUNK)) {
504 Tcl_SetObjErrorCode(ip, Tcl_NewStringObj(buf,-1));
505 snprintf(buf,sizeof(buf),"%lu",(unsigned long)logjunkpos);
507 Tcl_AppendResult(ip, "syntax error (junk) in .jrn during"
508 " (dirty) open, at file position ", buf, (char*)0);
512 rc= infocb3(ip, rw, "open-dirty-junk", "errorfpos=%luby", buf,
513 (unsigned long)logjunkpos);
516 r= fseeko(rw->logfile, logrecstart, SEEK_SET);
517 if (r) PE("failed to fseeko .jrn before junk during dirty open");
519 r= ftruncate(fileno(rw->logfile), logrecstart);
520 if (r) PE("ftruncate .jrn to chop junk during dirty open");
526 /* now log is positioned for appending and everything is read */
539 int cht_do_cdbwr_open_okjunk(ClientData cd, Tcl_Interp *ip, const char *pathb,
540 Tcl_Obj *on_info, Tcl_Obj *on_lexminval,
542 return cht_do_cdbwr_open(cd,ip,pathb,on_info,on_lexminval,result);
545 /*==================== COMPACTION ====================*/
547 struct ht_forall_ctx {
548 struct cdb_make cdbm;
552 const char *lexminval; /* may be invalid if lexminvall <= 0 */
555 /*---------- helper functions ----------*/
557 static int expiredp(const HashValue *val, struct ht_forall_ctx *a) {
559 if (!val->len || a->lexminvall<=0) return 0;
560 l= val->len < a->lexminvall ? val->len : a->lexminvall;
561 r= memcmp(val->data, a->lexminval, l);
564 return val->len < a->lexminvall;
567 static int delete_ifexpired(const char *key, HashValue *val,
568 struct ht_forall_ctx *a) {
569 if (!expiredp(val, a)) return 0;
571 /* we don't actually need to realloc it to free the memory because
572 * this will shortly all be deleted as part of the compaction */
576 static int addto_cdb(const char *key, HashValue *val,
577 struct ht_forall_ctx *a) {
578 return cdb_make_add(&a->cdbm, key, strlen(key), val->data, val->len);
581 static int addto_main(const char *key, HashValue *val,
582 struct ht_forall_ctx *a) {
584 return writerecord(a->mainfile, key, val);
587 /*---------- compact main entrypoint ----------*/
589 static int compact_core(Tcl_Interp *ip, Rw *rw, unsigned long logsz,
591 /* creates new .cdb and .main
593 * leaves .jrn with old data
594 * leaves cdb fd open onto old db
595 * leaves logincore full of crap
598 int cdbfd, cdbmaking;
599 off_t errpos, newmainsz;
602 struct ht_forall_ctx a;
608 a.reccount= reccount_r;
610 r= fclose(rw->logfile);
611 if (r) { rc= cht_posixerr(ip, errno, "probable data loss! failed to fclose"
612 " logfile during compact"); goto x_rc; }
615 rc= infocb(ip, rw, "compact-start", "log=%luby main=%luby",
616 logsz, (unsigned long)rw->mainsz);
619 if (cht_scriptinv_interp(&rw->on_lexminval)) {
620 rc= cht_scriptinv_invoke_fg(&rw->on_lexminval, 0,0);
623 res= Tcl_GetObjResult(ip); assert(res);
624 a.lexminval= Tcl_GetStringFromObj(res, &a.lexminvall);
627 /* we rely not calling Tcl_Eval during the actual compaction;
628 * if we did Tcl_Eval then the interp result would be trashed.
630 rc= ht_forall(&rw->logincore, delete_ifexpired, &a);
636 /* merge unsuperseded records from main into hash table */
638 a.mainfile= fopen(pathbuf_sfx(&rw->pbsome,".main"), "r");
639 if (!a.mainfile) PE("failed to open .main for reading during compact");
642 r= readstorelogrecord(a.mainfile, &rw->logincore,
645 if (ferror(a.mainfile)) { rc= cht_posixerr(ip, errno, "error reading"
646 " .main during compact"); goto x_rc; }
649 } else if (r==-1 || r==-2) {
650 errpos= ftello(a.mainfile);
651 if (errpos<0) PE("ftello .main during report of syntax error");
652 snprintf(buf,sizeof(buf), "CDB %s MAIN %lu",
653 r==-1 ? "TRUNCATED" : "SYNTAX", (unsigned long)errpos);
654 Tcl_SetObjErrorCode(ip, Tcl_NewStringObj(buf,-1));
655 snprintf(buf,sizeof(buf), "%lu", (unsigned long)errpos);
658 r==-1 ? "unexpected eof (truncated file)"
659 " in .main during compact, at file position "
661 " in .main during compact, at file position ",
674 cdbfd= open(pathbuf_sfx(&rw->pbsome,".tmp"), O_WRONLY|O_CREAT|O_TRUNC, 0666);
675 if (cdbfd<0) PE("create .tmp for new cdb during compact");
677 r= cdb_make_start(&a.cdbm, cdbfd);
678 if (r) PE("cdb_make_start during compact");
681 r= ht_forall(&rw->logincore, addto_cdb, &a);
682 if (r) PE("cdb_make_add during compact");
684 r= cdb_make_finish(&a.cdbm);
685 if(r) PE("cdb_make_finish during compact");
688 r= fdatasync(cdbfd); if (r) PE("fdatasync new cdb during compact");
689 r= close(cdbfd); if (r) PE("close new cdb during compact");
692 r= rename(rw->pbsome.buf, pathbuf_sfx(&rw->pbother,".cdb"));
693 if (r) PE("install new .cdb during compact");
695 /* create new main */
697 a.mainfile= fopen(pathbuf_sfx(&rw->pbsome,".tmp"), "w");
698 if (!a.mainfile) PE("create .tmp for new main during compact");
700 r= ht_forall(&rw->logincore, addto_main, &a);
701 if (r) { rc= cht_posixerr(ip, r, "error writing to new .main"
702 " during compact"); goto x_rc; }
704 r= putc('\n', a.mainfile);
705 if (r==EOF) PE("write trailing \n to main during compact");
707 r= fflush(a.mainfile); if (r) PE("fflush new main during compact");
708 r= fdatasync(fileno(a.mainfile));
709 if (r) PE("fdatasync new main during compact");
711 newmainsz= ftello(a.mainfile);
712 if (newmainsz<0) PE("ftello new main during compact");
714 r= fclose(a.mainfile); if (r) PE("fclose new main during compact");
717 r= rename(rw->pbsome.buf, pathbuf_sfx(&rw->pbother,".main"));
718 if (r) PE("install new .main during compact");
720 rw->mainsz= newmainsz;
724 rc= infocb(ip, rw, "compact-end", "main=%luby nrecs=%ld",
725 (unsigned long)rw->mainsz, *a.reccount);
731 if (a.mainfile) fclose(a.mainfile);
732 if (cdbmaking) cdb_make_finish(&a.cdbm);
734 remove(pathbuf_sfx(&rw->pbsome,".tmp")); /* for tidyness */
738 /*---------- Closing ----------*/
740 static int compact_forclose(Tcl_Interp *ip, Rw *rw, long *reccount_r) {
744 logsz= ftello(rw->logfile);
745 if (logsz < 0) PE("ftello logfile (during tidy close)");
747 rc= compact_core(ip, rw, logsz, reccount_r); if (rc) goto x_rc;
749 r= remove(pathbuf_sfx(&rw->pbsome,".jrn"));
750 if (r) PE("remove .jrn (during tidy close)");
757 int cht_do_cdbwr_close(ClientData cd, Tcl_Interp *ip, void *rw_v) {
763 if (rw->autocompact) rc= compact_forclose(ip, rw, &reccount);
768 logsz= ftello(rw->logfile);
770 rc= cht_posixerr(ip, errno, "ftell logfile during close info");
772 rc= infocb(ip, rw, "close", "main=%luby log=%luby",
774 } else if (reccount>=0) {
775 rc= infocb(ip, rw, "close", "main=%luby nrecs=%ld",
776 rw->mainsz, reccount);
778 rc= infocb(ip, rw, "close", "main=%luby", rw->mainsz);
781 rc_close= rw_close(ip,rw);
782 if (rc_close) rc= rc_close;
784 cht_tabledataid_disposing(ip, rw_v, &cdbtcl_rwdatabases);
789 /*---------- Other compaction-related entrypoints ----------*/
791 static int compact_keepopen(Tcl_Interp *ip, Rw *rw, int force) {
796 logsz= ftello(rw->logfile);
797 if (logsz < 0) return cht_posixerr(ip, errno, "ftell .jrn"
798 " during compact check or force");
800 if (!force && logsz < rw->mainsz / 3 + 1000) return TCL_OK;
801 /* Test case: ^^^ testing best value for this
802 * main=9690434by nrecs=122803 read all in one go
803 * no autocompact, : 6.96user 0.68system 0:08.93elapsed
804 * auto, mulitplier 2: 7.10user 0.79system 0:09.54elapsed
805 * auto, unity: 7.80user 0.98system 0:11.84elapsed
806 * auto, divisor 2: 8.23user 1.05system 0:13.30elapsed
807 * auto, divisor 3: 8.55user 1.12system 0:12.88elapsed
808 * auto, divisor 5: 9.95user 1.43system 0:15.72elapsed
811 rc= compact_core(ip, rw, logsz, &reccount); if (rc) goto x_rc;
813 maybe_close(rw->cdb_fd);
815 ht_destroy(&rw->logincore);
816 ht_setup(&rw->logincore);
818 rw->cdb_fd= open(pathbuf_sfx(&rw->pbsome,".cdb"), O_RDONLY);
819 if (rw->cdb_fd < 0) PE("reopen .cdb after compact");
821 rc= cdbinit(ip, rw); if (rc) goto x_rc;
823 rw->logfile= fopen(pathbuf_sfx(&rw->pbsome,".jrn"), "w");
824 if (!rw->logfile) PE("reopen .jrn after compact");
826 r= fsync(fileno(rw->logfile)); if (r) PE("fsync .jrn after compact reopen");
831 /* doom! all updates fail after this (because rw->logfile is 0), and
832 * we may be using a lot more RAM than would be ideal. Program will
833 * have to reopen if it really wants sanity. */
837 int cht_do_cdbwr_compact_force(ClientData cd, Tcl_Interp *ip, void *rw_v) {
838 return compact_keepopen(ip, rw_v, 1);
840 int cht_do_cdbwr_compact_check(ClientData cd, Tcl_Interp *ip, void *rw_v) {
841 return compact_keepopen(ip, rw_v, 0);
844 int cht_do_cdbwr_compact_explicit(ClientData cd, Tcl_Interp *ip, void *rw_v) {
849 int cht_do_cdbwr_compact_auto(ClientData cd, Tcl_Interp *ip, void *rw_v) {
855 /*---------- Updateing ----------*/
857 static int update(Tcl_Interp *ip, Rw *rw, const char *key,
858 const Byte *data, int dlen) {
862 if (!rw->logfile) return cht_staticerr
863 (ip, "previous compact failed; cdbwr must be closed and reopened "
864 "before any further updates", "CDB BROKEN");
866 val= htv_prep(dlen); assert(val);
867 memcpy(htv_fillptr(val), data, dlen);
869 r= writerecord(rw->logfile, key, val);
870 if (!r) r= fflush(rw->logfile);
871 if (r) PE("write update to logfile");
873 ht_update(&rw->logincore, key, val);
875 if (!rw->autocompact) return TCL_OK;
876 return compact_keepopen(ip, rw, 0);
883 int cht_do_cdbwr_update(ClientData cd, Tcl_Interp *ip,
884 void *rw_v, const char *key, Tcl_Obj *value) {
887 data= Tcl_GetStringFromObj(value, &dlen); assert(data);
888 return update(ip, rw_v, key, data, dlen);
891 int cht_do_cdbwr_update_hb(ClientData cd, Tcl_Interp *ip,
892 void *rw_v, const char *key, HBytes_Value value) {
893 return update(ip, rw_v, key, cht_hb_data(&value), cht_hb_len(&value));
896 int cht_do_cdbwr_delete(ClientData cd, Tcl_Interp *ip, void *rw_v,
898 return update(ip, rw_v, key, 0, 0);
901 /*---------- Lookups ----------*/
903 static int lookup_rw(Tcl_Interp *ip, void *rw_v, const char *key,
904 const Byte **data_r, int *len_r /* -1 => notfound */) {
906 const HashValue *val;
908 val= ht_lookup(&rw->logincore, key);
910 if (val->len) { *data_r= val->data; *len_r= val->len; return TCL_OK; }
911 else { *data_r= 0; *len_r= -1; return TCL_OK; }
914 return cht_cdb_lookup_cdb(ip, &rw->cdb, key, strlen(key), data_r, len_r);
917 int cht_do_cdbwr_lookup(ClientData cd, Tcl_Interp *ip, void *rw_v,
918 const char *key, Tcl_Obj *def,
923 r= lookup_rw(ip, rw_v, key, &data, &dlen); if (r) return r;
924 return cht_cdb_donesomelookup(ip, rw_v, def, result, data, dlen,
925 cht_cdb_storeanswer_string);
928 int cht_do_cdbwr_lookup_hb(ClientData cd, Tcl_Interp *ip, void *rw_v,
929 const char *key, Tcl_Obj *def,
934 r= lookup_rw(ip, rw_v, key, &data, &dlen); if (r) return r;
935 return cht_cdb_donesomelookup(ip, rw_v, def, result, data, dlen,
936 cht_cdb_storeanswer_hb);