Enhancements to sqlite_dbpage() so that it accepts INSERT statements that can

extend or truncate the database.  Add the sqlite3-rsync utility program that
make a copy of a live database over SSH.

FossilOrigin-Name: b7a8ce4c8c5fc6a3b4744d412d96f99d2452eb4086ad84472511da3b4d6afec6

9 files changed, 1985 insertions, 33 deletions

diff --git a/Makefile.in b/Makefile.in
index e359975d8..c9e27a4cc 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -700,6 +700,20 @@ sqldiff$(TEXE):	$(TOP)/tool/sqldiff.c sqlite3.lo sqlite3.h
 dbhash$(TEXE):	$(TOP)/tool/dbhash.c sqlite3.lo sqlite3.h
 	$(LTLINK) -o $@ $(TOP)/tool/dbhash.c sqlite3.lo $(TLIBS)
 
+RSYNC_SRC = \
+  $(TOP)/tool/sqlite3-rsync.c \
+  sqlite3.c
+
+RSYNC_OPT = \
+  -DSQLITE_ENABLE_DBPAGE_VTAB \
+  -USQLITE_THREADSAFE \
+  -DSQLITE_THREADSAFE=0 \
+  -DSQLITE_OMIT_LOAD_EXTENSION \
+  -DSQLITE_OMIT_DEPRECATED
+
+sqlite3-rsync$(TEXE):	$(RSYNC_SRC)
+	$(TCC) -o $@ $(RSYNC_OPT) $(RSYNC_SRC) $(TLIBS)
+
 scrub$(TEXE):	$(TOP)/ext/misc/scrub.c sqlite3.lo
 	$(LTLINK) -o $@ -I. -DSCRUB_STANDALONE \
 		$(TOP)/ext/misc/scrub.c sqlite3.lo $(TLIBS)
@@ -1191,6 +1205,7 @@ SHELL_DEP = \
     $(TOP)/ext/misc/percentile.c \
     $(TOP)/ext/misc/regexp.c \
     $(TOP)/ext/misc/series.c \
+    $(TOP)/ext/misc/sha1.c \
     $(TOP)/ext/misc/shathree.c \
     $(TOP)/ext/misc/sqlar.c \
     $(TOP)/ext/misc/uint.c \
diff --git a/Makefile.msc b/Makefile.msc
index 41e5c1081..295e07b07 100644
--- a/Makefile.msc
+++ b/Makefile.msc
@@ -1867,6 +1867,19 @@ sqldiff.exe:	$(TOP)\tool\sqldiff.c $(TOP)\ext\consio\console_io.h $(TOP)\ext\con
 dbhash.exe:	$(TOP)\tool\dbhash.c $(SQLITE3C) $(SQLITE3H)
 	$(LTLINK) $(NO_WARN) $(TOP)\tool\dbhash.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)
 
+RSYNC_SRC = \
+  $(TOP)\tool\sqlite3-rsync.c \
+  $(SQLITE3C)
+
+RSYNC_OPT = \
+  -DSQLITE_ENABLE_DBPAGE_VTAB \
+  -DSQLITE_THREADSAFE=0 \
+  -DSQLITE_OMIT_LOAD_EXTENSION \
+  -DSQLITE_OMIT_DEPRECATED
+
+sqlite3-rsync.exe:	$(RSYNC_SRC) $(LIBRESOBJS)
+	$(LTLINK) $(RSYNC_OPT) $(NO_WARN) $(RSYNC_SRC) /link $(LDFLAGS) $(LTLINKOPTS) $(LIBRESOBJS)
+
 scrub.exe:	$(TOP)\ext\misc\scrub.c $(SQLITE3C) $(SQLITE3H)
 	$(LTLINK) $(NO_WARN) -DSCRUB_STANDALONE=1 $(TOP)\ext\misc\scrub.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)
 
@@ -2317,6 +2330,7 @@ SHELL_DEP = \
     $(TOP)\ext\misc\percentile.c \
     $(TOP)\ext\misc\regexp.c \
     $(TOP)\ext\misc\series.c \
+    $(TOP)\ext\misc\sha1.c \
     $(TOP)\ext\misc\shathree.c \
     $(TOP)\ext\misc\sqlar.c \
     $(TOP)\ext\misc\uint.c \
diff --git a/ext/misc/sha1.c b/ext/misc/sha1.c
index 9790a1d87..07d797060 100644
--- a/ext/misc/sha1.c
+++ b/ext/misc/sha1.c
@@ -196,7 +196,8 @@ static void hash_step_vformat(
 ** zOut[].  zOut[] must be at least 41 bytes long. */
 static void hash_finish(
   SHA1Context *p,           /* The SHA1 context to finish and render */
-  char *zOut                /* Store hexadecimal hash here */
+  char *zOut,               /* Store hex or binary hash here */
+  int bAsBinary             /* 1 for binary hash, 0 for hex hash */
 ){
   unsigned int i;
   unsigned char finalcount[8];
@@ -215,11 +216,15 @@ static void hash_finish(
   for (i = 0; i < 20; i++){
     digest[i] = (unsigned char)((p->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
   }
-  for(i=0; i<20; i++){
-    zOut[i*2] = zEncode[(digest[i]>>4)&0xf];
-    zOut[i*2+1] = zEncode[digest[i] & 0xf];
+  if( bAsBinary ){
+    memcpy(zOut, digest, 20);
+  }else{
+    for(i=0; i<20; i++){
+      zOut[i*2] = zEncode[(digest[i]>>4)&0xf];
+      zOut[i*2+1] = zEncode[digest[i] & 0xf];
+    }
+    zOut[i*2]= 0;
   }
-  zOut[i*2]= 0;
 }
 /* End of the hashing logic
 *****************************************************************************/
@@ -251,8 +256,13 @@ static void sha1Func(
   }else{
     hash_step(&cx, sqlite3_value_text(argv[0]), nByte);
   }
-  hash_finish(&cx, zOut);
-  sqlite3_result_text(context, zOut, 40, SQLITE_TRANSIENT);
+  if( sqlite3_user_data(context)!=0 ){
+    hash_finish(&cx, zOut, 1);
+    sqlite3_result_blob(context, zOut, 20, SQLITE_TRANSIENT);
+  }else{
+    hash_finish(&cx, zOut, 0);
+    sqlite3_result_blob(context, zOut, 40, SQLITE_TRANSIENT);
+  }
 }
 
 /*
@@ -365,7 +375,7 @@ static void sha1QueryFunc(
     }
     sqlite3_finalize(pStmt);
   }
-  hash_finish(&cx, zOut);
+  hash_finish(&cx, zOut, 0);
   sqlite3_result_text(context, zOut, 40, SQLITE_TRANSIENT);
 }
 
@@ -379,11 +389,17 @@ int sqlite3_sha_init(
   const sqlite3_api_routines *pApi
 ){
   int rc = SQLITE_OK;
+  static int one = 1;
   SQLITE_EXTENSION_INIT2(pApi);
   (void)pzErrMsg;  /* Unused parameter */
   rc = sqlite3_create_function(db, "sha1", 1, 
                        SQLITE_UTF8 | SQLITE_INNOCUOUS | SQLITE_DETERMINISTIC,
-                               0, sha1Func, 0, 0);
+                                0, sha1Func, 0, 0);
+  if( rc==SQLITE_OK ){
+    rc = sqlite3_create_function(db, "sha1b", 1, 
+                       SQLITE_UTF8 | SQLITE_INNOCUOUS | SQLITE_DETERMINISTIC,
+                          (void*)&one, sha1Func, 0, 0);
+  }
   if( rc==SQLITE_OK ){
     rc = sqlite3_create_function(db, "sha1_query", 1, 
                                  SQLITE_UTF8|SQLITE_DIRECTONLY, 0,
diff --git a/main.mk b/main.mk
index 17284dd9f..ba1ef2484 100644
--- a/main.mk
+++ b/main.mk
@@ -568,6 +568,19 @@ dbhash$(EXE):	$(TOP)/tool/dbhash.c sqlite3.c sqlite3.h
 	$(TCCX) -o dbhash$(EXE) -DSQLITE_THREADSAFE=0 \
 		$(TOP)/tool/dbhash.c sqlite3.c $(TLIBS) $(THREADLIB)
 
+RSYNC_SRC = \
+  $(TOP)/tool/sqlite3-rsync.c \
+  sqlite3.c
+
+RSYNC_OPT = \
+  -DSQLITE_ENABLE_DBPAGE_VTAB \
+  -DSQLITE_THREADSAFE=0 \
+  -DSQLITE_OMIT_LOAD_EXTENSION \
+  -DSQLITE_OMIT_DEPRECATED
+
+sqlite3-rsync$(EXE):	$(RSYNC_SRC)
+	$(TCC) -o $@ $(RSYNC_OPT) $(RSYNC_SRC) $(TLIBS)
+
 scrub$(EXE):	$(TOP)/ext/misc/scrub.c sqlite3.o
 	$(TCC) -I. -DSCRUB_STANDALONE -o scrub$(EXE) $(TOP)/ext/misc/scrub.c sqlite3.o $(THREADLIB)
 
@@ -768,6 +781,7 @@ SHELL_DEP = \
     $(TOP)/ext/misc/percentile.c \
     $(TOP)/ext/misc/regexp.c \
     $(TOP)/ext/misc/series.c \
+    $(TOP)/ext/misc/sha1.c \
     $(TOP)/ext/misc/shathree.c \
     $(TOP)/ext/misc/sqlar.c \
     $(TOP)/ext/misc/uint.c \
diff --git a/manifest b/manifest
index 147bf8dbf..877993cdf 100644
--- a/manifest
+++ b/manifest
@@ -1,11 +1,11 @@
-C Close\sthe\sdb\sas\ssqlite3_analyzer\sexits.\s(See\s[forum:af384c2315d9718a|forum\spost,\s"sqlite3_analyzer\snot\sclosing\sWAL-mode\sdb\scleanly"\s].)
-D 2024-09-13T16:10:04.337
+C Enhancements\sto\ssqlite_dbpage()\sso\sthat\sit\saccepts\sINSERT\sstatements\sthat\scan\nextend\sor\struncate\sthe\sdatabase.\s\sAdd\sthe\ssqlite3-rsync\sutility\sprogram\sthat\nmake\sa\scopy\sof\sa\slive\sdatabase\sover\sSSH.
+D 2024-09-14T16:39:02.179
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
-F Makefile.in 7753650b4204e3ccd55a4e6a0d73a5a01f737dcefb099d901ce1de5df9d0b82c
+F Makefile.in 31368ad3e1800bb5f311adede543ee456ca7d2595403c7f131797ae65a7d415c
 F Makefile.linux-gcc f3842a0b1efbfbb74ac0ef60e56b301836d05b4d867d014f714fa750048f1ab6
-F Makefile.msc 6e8925dca6dc8c3e9cce042bbf347d20164653e63aeafcf6f6a28e27cf976d8b
+F Makefile.msc 62ace0005c53b52f189c20c1d6d8fa4dbd2a37c90d9c1362b60f4fb4c841fa15
 F README.md c3c0f19532ce28f6297a71870f3c7b424729f0e6d9ab889616d3587dd2332159
 F VERSION 0db40f92c04378404eb45bff93e9e42c148c7e54fd3da99469ed21e22411f5a6
 F aclocal.m4 a5c22d164aff7ed549d53a90fa56d56955281f50
@@ -420,7 +420,7 @@ F ext/misc/remember.c add730f0f7e7436cd15ea3fd6a90fd83c3f706ab44169f7f048438b7d6
 F ext/misc/rot13.c 51ac5f51e9d5fd811db58a9c23c628ad5f333c173f1fc53c8491a3603d38556c
 F ext/misc/scrub.c 2a44b0d44c69584c0580ad2553f6290a307a49df4668941d2812135bfb96a946
 F ext/misc/series.c a6089b5e8e3002bd1e5d9877cee6aead0b9a6426e406c09a399817db9e9ae823
-F ext/misc/sha1.c 4011aef176616872b2a0d5bccf0ecfb1f7ce3fe5c3d107f3a8e949d8e1e3f08d
+F ext/misc/sha1.c cb5002148c2661b5946f34561701e9105e9d339b713ec8ac057fd888b196dcb9
 F ext/misc/shathree.c 1821d90a0040c9accdbe3e3527d378d30569475d758aa70f6848924c0b430e8c
 F ext/misc/showauth.c 732578f0fe4ce42d577e1c86dc89dd14a006ab52
 F ext/misc/spellfix.c c0aa7b80d6df45f7da59d912b38752bcac1af53a5766966160e6c5cdd397dbea
@@ -687,7 +687,7 @@ F ext/wasm/wasmfs.make 8a4955882aaa0783b3f60a9484a1f0f3d8b6f775c0fcd17c082f31966
 F install-sh 9d4de14ab9fb0facae2f48780b874848cbf2f895 x
 F ltmain.sh 3ff0879076df340d2e23ae905484d8c15d5fdea8
 F magic.txt 5ade0bc977aa135e79e3faaea894d5671b26107cc91e70783aa7dc83f22f3ba0
-F main.mk 391342c3c0907f57bbb9ab60ce4b3cfe1ea61161996b449033984673d18980fd
+F main.mk 8b9c0252aef57b5b2a10f34b8b46e89f9ed06bdccef1df98673a12f34e9b3e79
 F mptest/config01.test 3c6adcbc50b991866855f1977ff172eb6d901271
 F mptest/config02.test 4415dfe36c48785f751e16e32c20b077c28ae504
 F mptest/crash01.test 61e61469e257df0850df4293d7d4d6c2af301421
@@ -714,7 +714,7 @@ F src/callback.c db3a45e376deff6a16c0058163fe0ae2b73a2945f3f408ca32cf74960b28d49
 F src/complete.c a3634ab1e687055cd002e11b8f43eb75c17da23e
 F src/ctime.c b224d3db0f28c4a5f1407c50107a0a8133bd244ff3c7f6f8cedeb896a8cf1b64
 F src/date.c 89ce1ff20512a7fa5070ba6e7dd5c171148ca7d580955795bf97c79c2456144a
-F src/dbpage.c f8c93e845d1093554247c1e757cb443fc48ffbcb112cecfdebeca4b6aa6e5c6e
+F src/dbpage.c 12e49515d67d4a59625d71f9aa42499556cfdc2e4f1ea49086e674a7f47f46e5
 F src/dbstat.c 73362c0df0f40ad5523a6f5501224959d0976757b511299bf892313e79d14f5c
 F src/delete.c 444c4d1eaac40103461e3b6f0881846dd3aafc1cec1dd169d3482fa331667da7
 F src/expr.c 6d5f2c38fe3ec06a7eac599dac822788b36064124e20112a844e9cd5156cb239
@@ -768,7 +768,7 @@ F src/random.c 606b00941a1d7dd09c381d3279a058d771f406c5213c9932bbd93d5587be4b9c
 F src/resolve.c 2c127880c0634962837f16f2f48a295e514357af959330cc038de73015d5b5e8
 F src/rowset.c 8432130e6c344b3401a8874c3cb49fefe6873fec593294de077afea2dce5ec97
 F src/select.c 4b14337a2742f0c0beeba490e9a05507e9b4b12184b9cd12773501d08d48e3fe
-F src/shell.c.in 470db843788d74234cc1e6873ac51c0ae6529994a52146fefe2e77c0754cbf96
+F src/shell.c.in 375f8a183126be96ec73db4e42c57917ff10a0900846b1b722dd4f8cef537812
 F src/sqlite.h.in 77f55bd1978a04a14db211732f0a609077cf60ba4ccf9baf39988f508945419c
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h 3f046c04ea3595d6bfda99b781926b17e672fd6d27da2ba6d8d8fc39981dcb54
@@ -2174,6 +2174,7 @@ F tool/speedtest8inst1.c 7ce07da76b5e745783e703a834417d725b7d45fd
 F tool/spellsift.tcl 52b4b04dc4333c7ab024f09d9d66ed6b6f7c6eb00b38497a09f338fa55d40618 x
 F tool/split-sqlite3c.tcl 5aa60643afca558bc732b1444ae81a522326f91e1dc5665b369c54f09e20de60
 F tool/sqldiff.c 847fc8fcfddf5ce4797b7394cad6372f2f5dc17d8186e2ef8fb44d50fae4f44a
+F tool/sqlite3-rsync.c f34c43d88141dff62fb83067059bca9ec79d85fbc5be92bfe0d95db95ce21107
 F tool/sqlite3_analyzer.c.in 8da2b08f56eeac331a715036cf707cc20f879f231362be0c22efd682e2b89b4f
 F tool/sqltclsh.c.in 1bcc2e9da58fadf17b0bf6a50e68c1159e602ce057210b655d50bad5aaaef898
 F tool/sqltclsh.tcl 862f4cf1418df5e1315b5db3b5ebe88969e2a784525af5fbf9596592f14ed848
@@ -2212,8 +2213,8 @@ F vsixtest/vsixtest.tcl 6195aba1f12a5e10efc2b8c0009532167be5e301abe5b31385638080
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 4cad385b90eaca2d90e3375e473472145af4134160b81097a8535d06638c2e4a
-R 506f0349cf71d4b56754bbc21843c2e9
-U larrybr
-Z 8cfad2cb033fbf4c7a29251fd8b9a990
+P 94ceac98845e31249b656dcdb8a58f456b9212dc83968ea333852a66d72a0dae 9961334c8007e7cb6ae55885075b74acddc4fa701b359cf67e0f3c237d7eba4a
+R 35bd9e1a3f1cc54ea6c1adcfd7040bcd
+U drh
+Z 2f1609bf1d6f611498fb654c8834250d
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.uuid b/manifest.uuid
index 0888cebb1..4facd3596 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-94ceac98845e31249b656dcdb8a58f456b9212dc83968ea333852a66d72a0dae
+b7a8ce4c8c5fc6a3b4744d412d96f99d2452eb4086ad84472511da3b4d6afec6
diff --git a/src/dbpage.c b/src/dbpage.c
index 9740b418a..42b24f9b8 100644
--- a/src/dbpage.c
+++ b/src/dbpage.c
@@ -28,7 +28,13 @@
 **
 ** The data field of sqlite_dbpage table can be updated.  The new
 ** value must be a BLOB which is the correct page size, otherwise the
-** update fails.  Rows may not be deleted or inserted.
+** update fails.  INSERT operations also work, and operate as if they
+** where REPLACE.  The size of the database can be extended by INSERT-ing
+** new pages on the end.
+**
+** Rows may not be deleted.  However, doing an INSERT to page number N
+** with NULL page data causes the N-th page and all subsequent pages to be
+** deleted and the database to be truncated.
 */
 
 #include "sqliteInt.h"   /* Requires access to internal data structures */
@@ -51,6 +57,8 @@ struct DbpageCursor {
 struct DbpageTable {
   sqlite3_vtab base;              /* Base class.  Must be first */
   sqlite3 *db;                    /* The database */
+  int nTrunc;                     /* Entries in aTrunc[] */
+  Pgno *aTrunc;                   /* Truncation size for each database */
 };
 
 /* Columns */
@@ -59,7 +67,6 @@ struct DbpageTable {
 #define DBPAGE_COLUMN_SCHEMA  2
 
 
-
 /*
 ** Connect to or create a dbpagevfs virtual table.
 */
@@ -100,6 +107,8 @@ static int dbpageConnect(
 ** Disconnect from or destroy a dbpagevfs virtual table.
 */
 static int dbpageDisconnect(sqlite3_vtab *pVtab){
+  DbpageTable *pTab = (DbpageTable *)pVtab;
+  sqlite3_free(pTab->aTrunc);
   sqlite3_free(pVtab);
   return SQLITE_OK;
 }
@@ -325,6 +334,7 @@ static int dbpageUpdate(
   Btree *pBt;
   Pager *pPager;
   int szPage;
+  int isInsert;
 
   (void)pRowid;
   if( pTab->db->flags & SQLITE_Defensive ){
@@ -337,18 +347,20 @@ static int dbpageUpdate(
   }
   if( sqlite3_value_type(argv[0])==SQLITE_NULL ){
     pgno = (Pgno)sqlite3_value_int(argv[2]);
+    isInsert = 1;
   }else{
     pgno = sqlite3_value_int(argv[0]);
     if( (Pgno)sqlite3_value_int(argv[1])!=pgno ){
       zErr = "cannot insert";
       goto update_fail;
     }
+    isInsert = 0;
   }
   if( sqlite3_value_type(argv[4])==SQLITE_NULL ){
     iDb = 0;
   }else{
     const char *zSchema = (const char*)sqlite3_value_text(argv[4]);
-    iDb = zSchema ? sqlite3FindDbName(pTab->db, zSchema) : -1;
+    iDb = sqlite3FindDbName(pTab->db, zSchema);
     if( iDb<0 ){
       zErr = "no such schema";
       goto update_fail;
@@ -363,18 +375,31 @@ static int dbpageUpdate(
   if( sqlite3_value_type(argv[3])!=SQLITE_BLOB 
    || sqlite3_value_bytes(argv[3])!=szPage
   ){
-    zErr = "bad page value";
-    goto update_fail;
+    if( sqlite3_value_type(argv[3])==SQLITE_NULL && isInsert ){
+      if( iDb>=pTab->nTrunc ){
+        testcase( pTab->aTrunc!=0 );
+        pTab->aTrunc = sqlite3_realloc(pTab->aTrunc, (iDb+1)*sizeof(Pgno));
+        if( pTab->aTrunc ){
+          int j;
+          for(j=pTab->nTrunc; j<iDb; j++) pTab->aTrunc[j] = 0;
+          pTab->nTrunc = iDb+1;
+        }else{
+          return SQLITE_NOMEM;
+        }
+      }
+      pTab->aTrunc[iDb] = pgno;
+    }else{
+      zErr = "bad page value";
+      goto update_fail;
+    }
   }
   pPager = sqlite3BtreePager(pBt);
   rc = sqlite3PagerGet(pPager, pgno, (DbPage**)&pDbPage, 0);
   if( rc==SQLITE_OK ){
     const void *pData = sqlite3_value_blob(argv[3]);
-    assert( pData!=0 || pTab->db->mallocFailed );
-    if( pData
-     && (rc = sqlite3PagerWrite(pDbPage))==SQLITE_OK
-    ){
-      memcpy(sqlite3PagerGetData(pDbPage), pData, szPage);
+    if( (rc = sqlite3PagerWrite(pDbPage))==SQLITE_OK && pData ){
+      unsigned char *aPage = sqlite3PagerGetData(pDbPage);
+      memcpy(aPage, pData, szPage);
     }
   }
   sqlite3PagerUnref(pDbPage);
@@ -398,6 +423,26 @@ static int dbpageBegin(sqlite3_vtab *pVtab){
     Btree *pBt = db->aDb[i].pBt;
     if( pBt ) (void)sqlite3BtreeBeginTrans(pBt, 1, 0);
   }
+  if( pTab->nTrunc>0 ){
+    memset(pTab->aTrunc, 0, sizeof(pTab->aTrunc[0])*pTab->nTrunc);
+  }
+  return SQLITE_OK;
+}
+
+/* Invoke sqlite3PagerTruncate() as necessary, just prior to COMMIT
+*/
+static int dbpageSync(sqlite3_vtab *pVtab){
+  int iDb;
+  DbpageTable *pTab = (DbpageTable *)pVtab;
+
+  for(iDb=0; iDb<pTab->nTrunc; iDb++){
+    if( pTab->aTrunc[iDb]>0 ){
+      Btree *pBt = pTab->db->aDb[iDb].pBt;
+      Pager *pPager = sqlite3BtreePager(pBt);
+      sqlite3PagerTruncateImage(pPager, pTab->aTrunc[iDb]);
+      pTab->aTrunc[iDb] = 0;
+    }
+  }
   return SQLITE_OK;
 }
 
@@ -422,7 +467,7 @@ int sqlite3DbpageRegister(sqlite3 *db){
     dbpageRowid,                  /* xRowid - read data */
     dbpageUpdate,                 /* xUpdate */
     dbpageBegin,                  /* xBegin */
-    0,                            /* xSync */
+    dbpageSync,                   /* xSync */
     0,                            /* xCommit */
     0,                            /* xRollback */
     0,                            /* xFindMethod */
diff --git a/src/shell.c.in b/src/shell.c.in
index 9bc6c2566..2b0e506ed 100644
--- a/src/shell.c.in
+++ b/src/shell.c.in
@@ -1209,6 +1209,7 @@ INCLUDE test_windirent.c
 INCLUDE ../ext/misc/memtrace.c
 INCLUDE ../ext/misc/pcachetrace.c
 INCLUDE ../ext/misc/shathree.c
+INCLUDE ../ext/misc/sha1.c
 INCLUDE ../ext/misc/uint.c
 INCLUDE ../ext/misc/decimal.c
 INCLUDE ../ext/misc/percentile.c
@@ -5392,6 +5393,7 @@ static void open_db(ShellState *p, int openFlags){
 #ifndef SQLITE_OMIT_LOAD_EXTENSION
     sqlite3_enable_load_extension(p->db, 1);
 #endif
+    sqlite3_sha_init(p->db, 0, 0);
     sqlite3_shathree_init(p->db, 0, 0);
     sqlite3_uint_init(p->db, 0, 0);
     sqlite3_stmtrand_init(p->db, 0, 0);
diff --git a/tool/sqlite3-rsync.c b/tool/sqlite3-rsync.c
new file mode 100644
index 000000000..2a58125aa
--- /dev/null
+++ b/tool/sqlite3-rsync.c
@@ -0,0 +1,1845 @@
+/*
+** 2024-09-10
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This is a utility program that makes a copy of a live SQLite database
+** using a bandwidth-efficient protocol, similar to "rsync".
+*/
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <string.h>
+#include <stdarg.h>
+#include "sqlite3.h"
+
+static const char zUsage[] = 
+  "sqlite3-rsync ORIGIN REPLICA ?OPTIONS?\n"
+  "\n"
+  "One of ORIGIN or REPLICA is a pathname to a database on the local\n"
+  "machine and the other is of the form \"USER@HOST:PATH\" describing\n"
+  "a database on a remote machine.  This utility makes REPLICA into a\n"
+  "copy of ORIGIN\n"
+  "\n"
+  "OPTIONS:\n"
+  "\n"
+  "   --exe PATH    Name of the sqlite3-rsync program on the remote side\n"
+  "   --help        Show this help screen\n"
+  "   --ssh PATH    Name of the SSH program used to reach the remote side\n"
+  "   -v            Verbose.  Multiple v's for increasing output\n"
+  "   --version     Show detailed version information\n"
+;
+
+typedef unsigned char u8;
+
+/* Context for the run */
+typedef struct SQLiteRsync SQLiteRsync;
+struct SQLiteRsync {
+  const char *zOrigin;     /* Name of the origin */
+  const char *zReplica;    /* Name of the replica */
+  const char *zErrFile;    /* Append error messages to this file */
+  FILE *pOut;              /* Transmit to the other side */
+  FILE *pIn;               /* Receive from the other side */
+  FILE *pLog;              /* Duplicate output here if not NULL */
+  sqlite3 *db;             /* Database connection */
+  int nErr;                /* Number of errors encountered */
+  u8 eVerbose;             /* Bigger for more output.  0 means none. */
+  u8 bCommCheck;           /* True to debug the communication protocol */
+  u8 isRemote;             /* On the remote side of a connection */
+  u8 isReplica;            /* True if running on the replica side */
+  u8 iProtocol;            /* Protocol version number */
+  sqlite3_uint64 nOut;     /* Bytes transmitted */
+  sqlite3_uint64 nIn;      /* Bytes received */
+  unsigned int nPage;      /* Total number of pages in the database */
+  unsigned int szPage;     /* Database page size */
+  unsigned int nHashSent;  /* Hashes sent (replica to origin) */
+  unsigned int nPageSent;  /* Page contents sent (origin to replica) */
+};
+
+/* The version number of the protocol.  Sent in the *_BEGIN message
+** to verify that both sides speak the same dialect.
+*/
+#define PROTOCOL_VERSION  1
+
+
+/* Magic numbers to identify particular messages sent over the wire.
+*/
+#define ORIGIN_BEGIN    0x41     /* Initial message */
+#define ORIGIN_END      0x42     /* Time to quit */
+#define ORIGIN_ERROR    0x43     /* Error message from the remote */
+#define ORIGIN_PAGE     0x44     /* New page data */
+#define ORIGIN_TXN      0x45     /* Transaction commit */
+#define ORIGIN_MSG      0x46     /* Informational message */
+
+#define REPLICA_BEGIN   0x61     /* Welcome message */
+#define REPLICA_ERROR   0x62     /* Error.  Report and quit. */
+#define REPLICA_END     0x63     /* Replica wants to stop */
+#define REPLICA_HASH    0x64     /* One or more pages hashes to report */
+#define REPLICA_READY   0x65     /* Read to receive page content */
+#define REPLICA_MSG     0x66     /* Informational message */
+
+
+/****************************************************************************
+** Beginning of the popen2() implementation copied from Fossil  *************
+****************************************************************************/
+#ifdef _WIN32
+#include <windows.h>
+#include <fcntl.h>
+/*
+** Print a fatal error and quit.
+*/
+static void win32_fatal_error(const char *zMsg){
+  fprintf(stderr, "%s", zMsg);
+  exit(1);
+}
+extern int _open_osfhandle(intptr_t,int);
+#else
+#include <unistd.h>
+#include <signal.h>
+#include <sys/wait.h>
+#endif
+
+/*
+** The following macros are used to cast pointers to integers and
+** integers to pointers.  The way you do this varies from one compiler
+** to the next, so we have developed the following set of #if statements
+** to generate appropriate macros for a wide range of compilers.
+**
+** The correct "ANSI" way to do this is to use the intptr_t type.
+** Unfortunately, that typedef is not available on all compilers, or
+** if it is available, it requires an #include of specific headers
+** that vary from one machine to the next.
+**
+** This code is copied out of SQLite.
+*/
+#if defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
+# define INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
+# define PTR_TO_INT(X)  ((int)(__PTRDIFF_TYPE__)(X))
+#elif !defined(__GNUC__)       /* Works for compilers other than LLVM */
+# define INT_TO_PTR(X)  ((void*)&((char*)0)[X])
+# define PTR_TO_INT(X)  ((int)(((char*)X)-(char*)0))
+#elif defined(HAVE_STDINT_H)   /* Use this case if we have ANSI headers */
+# define INT_TO_PTR(X)  ((void*)(intptr_t)(X))
+# define PTR_TO_INT(X)  ((int)(intptr_t)(X))
+#else                          /* Generates a warning - but it always works */
+# define INT_TO_PTR(X)  ((void*)(X))
+# define PTR_TO_INT(X)  ((int)(X))
+#endif
+
+/* Register SQL functions provided by ext/misc/sha1.c */
+extern int sqlite3_sha_init(
+  sqlite3 *db,
+  char **pzErrMsg,
+  const sqlite3_api_routines *pApi
+);
+
+#ifdef _WIN32
+/*
+** On windows, create a child process and specify the stdin, stdout,
+** and stderr channels for that process to use.
+**
+** Return the number of errors.
+*/
+static int win32_create_child_process(
+  wchar_t *zCmd,       /* The command that the child process will run */
+  HANDLE hIn,          /* Standard input */
+  HANDLE hOut,         /* Standard output */
+  HANDLE hErr,         /* Standard error */
+  DWORD *pChildPid     /* OUT: Child process handle */
+){
+  STARTUPINFOW si;
+  PROCESS_INFORMATION pi;
+  BOOL rc;
+
+  memset(&si, 0, sizeof(si));
+  si.cb = sizeof(si);
+  si.dwFlags = STARTF_USESTDHANDLES;
+  SetHandleInformation(hIn, HANDLE_FLAG_INHERIT, TRUE);
+  si.hStdInput  = hIn;
+  SetHandleInformation(hOut, HANDLE_FLAG_INHERIT, TRUE);
+  si.hStdOutput = hOut;
+  SetHandleInformation(hErr, HANDLE_FLAG_INHERIT, TRUE);
+  si.hStdError  = hErr;
+  rc = CreateProcessW(
+     NULL,  /* Application Name */
+     zCmd,  /* Command-line */
+     NULL,  /* Process attributes */
+     NULL,  /* Thread attributes */
+     TRUE,  /* Inherit Handles */
+     0,     /* Create flags  */
+     NULL,  /* Environment */
+     NULL,  /* Current directory */
+     &si,   /* Startup Info */
+     &pi    /* Process Info */
+  );
+  if( rc ){
+    CloseHandle( pi.hProcess );
+    CloseHandle( pi.hThread );
+    *pChildPid = pi.dwProcessId;
+  }else{
+    win32_fatal_error("cannot create child process");
+  }
+  return rc!=0;
+}
+void *win32_utf8_to_unicode(const char *zUtf8){
+  int nByte = MultiByteToWideChar(CP_UTF8, 0, zUtf8, -1, 0, 0);
+  wchar_t *zUnicode = malloc( nByte*2 );
+  MultiByteToWideChar(CP_UTF8, 0, zUtf8, -1, zUnicode, nByte);
+  return zUnicode;
+}
+#endif
+
+/*
+** Create a child process running shell command "zCmd".  *ppOut is
+** a FILE that becomes the standard input of the child process.
+** (The caller writes to *ppOut in order to send text to the child.)
+** *ppIn is stdout from the child process.  (The caller
+** reads from *ppIn in order to receive input from the child.)
+** Note that *ppIn is an unbuffered file descriptor, not a FILE.
+** The process ID of the child is written into *pChildPid.
+**
+** Return the number of errors.
+*/
+static int popen2(
+  const char *zCmd,      /* Command to run in the child process */
+  FILE **ppIn,           /* Read from child using this file descriptor */
+  FILE **ppOut,          /* Write to child using this file descriptor */
+  int *pChildPid,        /* PID of the child process */
+  int bDirect            /* 0: run zCmd as a shell cmd.  1: run directly */
+){
+#ifdef _WIN32
+  HANDLE hStdinRd, hStdinWr, hStdoutRd, hStdoutWr, hStderr;
+  SECURITY_ATTRIBUTES saAttr;
+  DWORD childPid = 0;
+  int fd;
+
+  saAttr.nLength = sizeof(saAttr);
+  saAttr.bInheritHandle = TRUE;
+  saAttr.lpSecurityDescriptor = NULL;
+  hStderr = GetStdHandle(STD_ERROR_HANDLE);
+  if( !CreatePipe(&hStdoutRd, &hStdoutWr, &saAttr, 4096) ){
+    win32_fatal_error("cannot create pipe for stdout");
+  }
+  SetHandleInformation( hStdoutRd, HANDLE_FLAG_INHERIT, FALSE);
+
+  if( !CreatePipe(&hStdinRd, &hStdinWr, &saAttr, 4096) ){
+    win32_fatal_error("cannot create pipe for stdin");
+  }
+  SetHandleInformation( hStdinWr, HANDLE_FLAG_INHERIT, FALSE);
+
+  win32_create_child_process(win32_utf8_to_unicode(zCmd),
+                             hStdinRd, hStdoutWr, hStderr,&childPid);
+  *pChildPid = childPid;
+  fd = _open_osfhandle(PTR_TO_INT(hStdoutRd), 0);
+  *ppIn = fdopen(fd, "r");
+  fd = _open_osfhandle(PTR_TO_INT(hStdinWr), 0);
+  *ppOut = _fdopen(fd, "w");
+  CloseHandle(hStdinRd);
+  CloseHandle(hStdoutWr);
+  return 0;
+#else
+  int pin[2], pout[2];
+  *ppIn = 0;
+  *ppOut = 0;
+  *pChildPid = 0;
+
+  if( pipe(pin)<0 ){
+    return 1;
+  }
+  if( pipe(pout)<0 ){
+    close(pin[0]);
+    close(pin[1]);
+    return 1;
+  }
+  *pChildPid = fork();
+  if( *pChildPid<0 ){
+    close(pin[0]);
+    close(pin[1]);
+    close(pout[0]);
+    close(pout[1]);
+    *pChildPid = 0;
+    return 1;
+  }
+  signal(SIGPIPE,SIG_IGN);
+  if( *pChildPid==0 ){
+    int fd;
+    /* This is the child process */
+    close(0);
+    fd = dup(pout[0]);
+    if( fd!=0 ) {
+      fprintf(stderr,"popen2() failed to open file descriptor 0");
+      exit(1);
+    }
+    close(pout[0]);
+    close(pout[1]);
+    close(1);
+    fd = dup(pin[1]);
+    if( fd!=1 ){
+      fprintf(stderr,"popen() failed to open file descriptor 1");
+      exit(1);
+    }
+    close(pin[0]);
+    close(pin[1]);
+    if( bDirect ){
+      execl(zCmd, zCmd, (char*)0);
+    }else{
+      execl("/bin/sh", "/bin/sh", "-c", zCmd, (char*)0);
+    }
+    return 1;
+  }else{
+    /* This is the parent process */
+    close(pin[1]);
+    *ppIn = fdopen(pin[0], "r");
+    close(pout[0]);
+    *ppOut = fdopen(pout[1], "w");
+    return 0;
+  }
+#endif
+}
+
+/*
+** Close the connection to a child process previously created using
+** popen2().
+*/
+static void pclose2(FILE *pIn, FILE *pOut, int childPid){
+#ifdef _WIN32
+  /* Not implemented, yet */
+  fclose(pIn);
+  fclose(pOut);
+#else
+  fclose(pIn);
+  fclose(pOut);
+  while( waitpid(0, 0, WNOHANG)>0 ) {}
+#endif
+}
+/*****************************************************************************
+** End of the popen2() implementation copied from Fossil *********************
+*****************************************************************************/
+
+/*****************************************************************************
+** Beginning of the append_escaped_arg() routine, adapted from the Fossil   **
+** subroutine nameed blob_append_escaped_arg()                              **
+*****************************************************************************/
+/*
+** ASCII (for reference):
+**    x0  x1  x2  x3  x4  x5  x6  x7  x8  x9  xa  xb  xc  xd  xe  xf
+** 0x ^`  ^a  ^b  ^c  ^d  ^e  ^f  ^g  \b  \t  \n  ()  \f  \r  ^n  ^o
+** 1x ^p  ^q  ^r  ^s  ^t  ^u  ^v  ^w  ^x  ^y  ^z  ^{  ^|  ^}  ^~  ^
+** 2x ()  !   "   #   $   %   &   '   (   )   *   +   ,   -   .   /
+** 3x 0   1   2   3   4   5   6   7   8   9   :   ;   <   =   >   ?
+** 4x @   A   B   C   D   E   F   G   H   I   J   K   L   M   N   O
+** 5x P   Q   R   S   T   U   V   W   X   Y   Z   [   \   ]   ^   _
+** 6x `   a   b   c   d   e   f   g   h   i   j   k   l   m   n   o
+** 7x p   q   r   s   t   u   v   w   x   y   z   {   |   }   ~   ^_
+*/
+
+/*
+** Meanings for bytes in a filename:
+**
+**    0      Ordinary character.  No encoding required
+**    1      Needs to be escaped
+**    2      Illegal character.  Do not allow in a filename
+**    3      First byte of a 2-byte UTF-8
+**    4      First byte of a 3-byte UTF-8
+**    5      First byte of a 4-byte UTF-8
+*/
+static const char aSafeChar[256] = {
+#ifdef _WIN32
+/* Windows
+** Prohibit:  all control characters, including tab, \r and \n.
+** Escape:    (space) " # $ % & ' ( ) * ; < > ? [ ] ^ ` { | }
+*/
+/*  x0  x1  x2  x3  x4  x5  x6  x7  x8  x9  xa  xb  xc  xd  xe  xf  */
+     2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2, /* 0x */
+     2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2, /* 1x */
+     1,  0,  1,  1,  1,  1,  1,  1,  1,  1,  1,  0,  0,  0,  0,  0, /* 2x */
+     0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  1,  0,  1,  1, /* 3x */
+     1,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 4x */
+     0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  0,  1,  1,  0, /* 5x */
+     1,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 6x */
+     0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  1,  1,  0,  1, /* 7x */
+#else
+/* Unix
+** Prohibit:  all control characters, including tab, \r and \n
+** Escape:    (space) ! " # $ % & ' ( ) * ; < > ? [ \ ] ^ ` { | }
+*/
+/*  x0  x1  x2  x3  x4  x5  x6  x7  x8  x9  xa  xb  xc  xd  xe  xf  */
+     2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2, /* 0x */
+     2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2, /* 1x */
+     1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  0,  0,  0,  0,  0, /* 2x */
+     0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  1,  0,  1,  1, /* 3x */
+     1,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 4x */
+     0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  1,  1,  1,  0, /* 5x */
+     1,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 6x */
+     0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  1,  1,  0,  1, /* 7x */
+#endif
+    /* all bytes 0x80 through 0xbf are unescaped, being secondary
+    ** bytes to UTF8 characters.  Bytes 0xc0 through 0xff are the
+    ** first byte of a UTF8 character and do get escaped */
+     2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2, /* 8x */
+     2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2, /* 9x */
+     2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2, /* ax */
+     2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2, /* bx */
+     3,  3,  3,  3,  3,  3,  3,  3,  3,  3,  3,  3,  3,  3,  3,  3, /* cx */
+     3,  3,  3,  3,  3,  3,  3,  3,  3,  3,  3,  3,  3,  3,  3,  3, /* dx */
+     4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4, /* ex */
+     5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5  /* fx */
+};
+
+/*
+** pStr is a shell command under construction.  This routine safely
+** appends filename argument zIn.  It returns 0 on success or non-zero
+** on any error.
+**
+** The argument is escaped if it contains white space or other characters
+** that need to be escaped for the shell.  If zIn contains characters
+** that cannot be safely escaped, then throw a fatal error.
+**
+** If the isFilename argument is true, then the argument is expected
+** to be a filename.  As shell commands commonly have command-line
+** options that begin with "-" and since we do not want an attacker
+** to be able to invoke these switches using filenames that begin
+** with "-", if zIn begins with "-", prepend an additional "./"
+** (or ".\\" on Windows).
+*/
+int append_escaped_arg(sqlite3_str *pStr, const char *zIn, int isFilename){
+  int i;
+  unsigned char c;
+  int needEscape = 0;
+  int n = sqlite3_str_length(pStr);
+  char *z = sqlite3_str_value(pStr);
+
+  /* Look for illegal byte-sequences and byte-sequences that require
+  ** escaping.  No control-characters are allowed.  All spaces and
+  ** non-ASCII unicode characters and some punctuation characters require
+  ** escaping. */
+  for(i=0; (c = (unsigned char)zIn[i])!=0; i++){
+    if( aSafeChar[c] ){
+      unsigned char x = aSafeChar[c];
+      needEscape = 1;
+      if( x==2 ){
+        /* Bad ASCII character */
+        return 1;
+      }else if( x>2 ){
+        if( (zIn[i+1]&0xc0)!=0x80
+         || (x>=4 && (zIn[i+2]&0xc0)!=0x80)
+         || (x==5 && (zIn[i+3]&0xc0)!=0x80)
+        ){
+          /* Bad UTF8 character */
+          return 1;
+        }
+        i += x-2;
+      }
+    }
+  }
+
+  /* Separate from the previous argument by a space */
+  if( n>0 && !isspace(z[n-1]) ){
+    sqlite3_str_appendchar(pStr, 1, ' ');
+  }
+
+  /* Check for characters that need quoting */
+  if( !needEscape ){
+    if( isFilename && zIn[0]=='-' ){
+      sqlite3_str_appendchar(pStr, 1, '.');
+#if defined(_WIN32)
+      sqlite3_str_appendchar(pStr, 1, '\\');
+#else
+      sqlite3_str_appendchar(pStr, 1, '/');
+#endif
+    }
+    sqlite3_str_appendall(pStr, zIn);
+  }else{
+#if defined(_WIN32)
+    /* Quoting strategy for windows:
+    ** Put the entire name inside of "...".  Any " characters within
+    ** the name get doubled.
+    */
+    sqlite3_str_appendchar(pStr, 1, '"');
+    if( isFilename && zIn[0]=='-' ){
+      sqlite3_str_appendchar(pStr, 1, '.');
+      sqlite3_str_appendchar(pStr, 1, '\\');
+    }else if( zIn[0]=='/' ){
+      sqlite3_str_appendchar(pStr, 1, '.');
+    }
+    for(i=0; (c = (unsigned char)zIn[i])!=0; i++){
+      sqlite3_str_appendchar(pStr, 1, (char)c);
+      if( c=='"' ) sqlite3_str_appendchar(pStr, 1, '"');
+      if( c=='\\' ) sqlite3_str_appendchar(pStr, 1, '\\');
+      if( c=='%' && isFilename ) sqlite3_str_append(pStr, "%cd:~,%", 7);
+    }
+    sqlite3_str_appendchar(pStr, 1, '"');
+#else
+    /* Quoting strategy for unix:
+    ** If the name does not contain ', then surround the whole thing
+    ** with '...'.   If there is one or more ' characters within the
+    ** name, then put \ before each special character.
+    */
+    if( strchr(zIn,'\'') ){
+      if( isFilename && zIn[0]=='-' ){
+        sqlite3_str_appendchar(pStr, 1, '.');
+        sqlite3_str_appendchar(pStr, 1, '/');
+      }
+      for(i=0; (c = (unsigned char)zIn[i])!=0; i++){
+        if( aSafeChar[c] && aSafeChar[c]!=2 ){
+          sqlite3_str_appendchar(pStr, 1, '\\');
+        }
+        sqlite3_str_appendchar(pStr, 1, (char)c);
+      }
+    }else{
+      sqlite3_str_appendchar(pStr, 1, '\'');
+      if( isFilename && zIn[0]=='-' ){
+        sqlite3_str_appendchar(pStr, 1, '.');
+        sqlite3_str_appendchar(pStr, 1, '/');
+      }
+      sqlite3_str_appendall(pStr, zIn);
+      sqlite3_str_appendchar(pStr, 1, '\'');
+    }
+#endif
+  }
+  return 0;
+}
+/*****************************************************************************
+** End of the append_escaped_arg() routine, adapted from the Fossil         **
+*****************************************************************************/
+
+/*****************************************************************************
+** The Hash Engine
+**
+** This is basically SHA3, though with a 160-bit hash, and reducing the
+** number of rounds in the KeccakF1600 step function from 24 to 6.
+*/
+/*
+** Macros to determine whether the machine is big or little endian,
+** and whether or not that determination is run-time or compile-time.
+**
+** For best performance, an attempt is made to guess at the byte-order
+** using C-preprocessor macros.  If that is unsuccessful, or if
+** -DHash_BYTEORDER=0 is set, then byte-order is determined
+** at run-time.
+*/
+#ifndef Hash_BYTEORDER
+# if defined(i386)     || defined(__i386__)   || defined(_M_IX86) ||    \
+     defined(__x86_64) || defined(__x86_64__) || defined(_M_X64)  ||    \
+     defined(_M_AMD64) || defined(_M_ARM)     || defined(__x86)   ||    \
+     defined(__arm__)
+#   define Hash_BYTEORDER    1234
+# elif defined(sparc)    || defined(__ppc__)
+#   define Hash_BYTEORDER    4321
+# else
+#   define Hash_BYTEORDER 0
+# endif
+#endif
+
+typedef sqlite3_uint64 u64;
+
+/*
+** State structure for a Hash hash in progress
+*/
+typedef struct HashContext HashContext;
+struct HashContext {
+  union {
+    u64 s[25];                /* Keccak state. 5x5 lines of 64 bits each */
+    unsigned char x[1600];    /* ... or 1600 bytes */
+  } u;
+  unsigned nRate;        /* Bytes of input accepted per Keccak iteration */
+  unsigned nLoaded;      /* Input bytes loaded into u.x[] so far this cycle */
+  unsigned ixMask;       /* Insert next input into u.x[nLoaded^ixMask]. */
+  unsigned iSize;        /* 224, 256, 358, or 512 */
+};
+
+/*
+** A single step of the Keccak mixing function for a 1600-bit state
+*/
+static void KeccakF1600Step(HashContext *p){
+  int i;
+  u64 b0, b1, b2, b3, b4;
+  u64 c0, c1, c2, c3, c4;
+  u64 d0, d1, d2, d3, d4;
+  static const u64 RC[] = {
+    0x0000000000000001ULL,  0x0000000000008082ULL,
+    0x800000000000808aULL,  0x8000000080008000ULL,
+    0x000000000000808bULL,  0x0000000080000001ULL,
+    0x8000000080008081ULL,  0x8000000000008009ULL,
+    0x000000000000008aULL,  0x0000000000000088ULL,
+    0x0000000080008009ULL,  0x000000008000000aULL,
+    0x000000008000808bULL,  0x800000000000008bULL,
+    0x8000000000008089ULL,  0x8000000000008003ULL,
+    0x8000000000008002ULL,  0x8000000000000080ULL,
+    0x000000000000800aULL,  0x800000008000000aULL,
+    0x8000000080008081ULL,  0x8000000000008080ULL,
+    0x0000000080000001ULL,  0x8000000080008008ULL
+  };
+# define a00 (p->u.s[0])
+# define a01 (p->u.s[1])
+# define a02 (p->u.s[2])
+# define a03 (p->u.s[3])
+# define a04 (p->u.s[4])
+# define a10 (p->u.s[5])
+# define a11 (p->u.s[6])
+# define a12 (p->u.s[7])
+# define a13 (p->u.s[8])
+# define a14 (p->u.s[9])
+# define a20 (p->u.s[10])
+# define a21 (p->u.s[11])
+# define a22 (p->u.s[12])
+# define a23 (p->u.s[13])
+# define a24 (p->u.s[14])
+# define a30 (p->u.s[15])
+# define a31 (p->u.s[16])
+# define a32 (p->u.s[17])
+# define a33 (p->u.s[18])
+# define a34 (p->u.s[19])
+# define a40 (p->u.s[20])
+# define a41 (p->u.s[21])
+# define a42 (p->u.s[22])
+# define a43 (p->u.s[23])
+# define a44 (p->u.s[24])
+# define ROL64(a,x) ((a<<x)|(a>>(64-x)))
+
+  /*         v---- Number of rounds.  SHA3 has 24 here. */
+  for(i=0; i<6; i++){
+    c0 = a00^a10^a20^a30^a40;
+    c1 = a01^a11^a21^a31^a41;
+    c2 = a02^a12^a22^a32^a42;
+    c3 = a03^a13^a23^a33^a43;
+    c4 = a04^a14^a24^a34^a44;
+    d0 = c4^ROL64(c1, 1);
+    d1 = c0^ROL64(c2, 1);
+    d2 = c1^ROL64(c3, 1);
+    d3 = c2^ROL64(c4, 1);
+    d4 = c3^ROL64(c0, 1);
+
+    b0 = (a00^d0);
+    b1 = ROL64((a11^d1), 44);
+    b2 = ROL64((a22^d2), 43);
+    b3 = ROL64((a33^d3), 21);
+    b4 = ROL64((a44^d4), 14);
+    a00 =   b0 ^((~b1)&  b2 );
+    a00 ^= RC[i];
+    a11 =   b1 ^((~b2)&  b3 );
+    a22 =   b2 ^((~b3)&  b4 );
+    a33 =   b3 ^((~b4)&  b0 );
+    a44 =   b4 ^((~b0)&  b1 );
+
+    b2 = ROL64((a20^d0), 3);
+    b3 = ROL64((a31^d1), 45);
+    b4 = ROL64((a42^d2), 61);
+    b0 = ROL64((a03^d3), 28);
+    b1 = ROL64((a14^d4), 20);
+    a20 =   b0 ^((~b1)&  b2 );
+    a31 =   b1 ^((~b2)&  b3 );
+    a42 =   b2 ^((~b3)&  b4 );
+    a03 =   b3 ^((~b4)&  b0 );
+    a14 =   b4 ^((~b0)&  b1 );
+
+    b4 = ROL64((a40^d0), 18);
+    b0 = ROL64((a01^d1), 1);
+    b1 = ROL64((a12^d2), 6);
+    b2 = ROL64((a23^d3), 25);
+    b3 = ROL64((a34^d4), 8);
+    a40 =   b0 ^((~b1)&  b2 );
+    a01 =   b1 ^((~b2)&  b3 );
+    a12 =   b2 ^((~b3)&  b4 );
+    a23 =   b3 ^((~b4)&  b0 );
+    a34 =   b4 ^((~b0)&  b1 );
+
+    b1 = ROL64((a10^d0), 36);
+    b2 = ROL64((a21^d1), 10);
+    b3 = ROL64((a32^d2), 15);
+    b4 = ROL64((a43^d3), 56);
+    b0 = ROL64((a04^d4), 27);
+    a10 =   b0 ^((~b1)&  b2 );
+    a21 =   b1 ^((~b2)&  b3 );
+    a32 =   b2 ^((~b3)&  b4 );
+    a43 =   b3 ^((~b4)&  b0 );
+    a04 =   b4 ^((~b0)&  b1 );
+
+    b3 = ROL64((a30^d0), 41);
+    b4 = ROL64((a41^d1), 2);
+    b0 = ROL64((a02^d2), 62);
+    b1 = ROL64((a13^d3), 55);
+    b2 = ROL64((a24^d4), 39);
+    a30 =   b0 ^((~b1)&  b2 );
+    a41 =   b1 ^((~b2)&  b3 );
+    a02 =   b2 ^((~b3)&  b4 );
+    a13 =   b3 ^((~b4)&  b0 );
+    a24 =   b4 ^((~b0)&  b1 );
+  }
+}
+
+/*
+** Initialize a new hash.  iSize determines the size of the hash
+** in bits and should be one of 224, 256, 384, or 512.  Or iSize
+** can be zero to use the default hash size of 256 bits.
+*/
+static void HashInit(HashContext *p, int iSize){
+  memset(p, 0, sizeof(*p));
+  p->iSize = iSize;
+  if( iSize>=128 && iSize<=512 ){
+    p->nRate = (1600 - ((iSize + 31)&~31)*2)/8;
+  }else{
+    p->nRate = (1600 - 2*256)/8;
+  }
+#if Hash_BYTEORDER==1234
+  /* Known to be little-endian at compile-time. No-op */
+#elif Hash_BYTEORDER==4321
+  p->ixMask = 7;  /* Big-endian */
+#else
+  {
+    static unsigned int one = 1;
+    if( 1==*(unsigned char*)&one ){
+      /* Little endian.  No byte swapping. */
+      p->ixMask = 0;
+    }else{
+      /* Big endian.  Byte swap. */
+      p->ixMask = 7;
+    }
+  }
+#endif
+}
+
+/*
+** Make consecutive calls to the HashUpdate function to add new content
+** to the hash
+*/
+static void HashUpdate(
+  HashContext *p,
+  const unsigned char *aData,
+  unsigned int nData
+){
+  unsigned int i = 0;
+  if( aData==0 ) return;
+#if Hash_BYTEORDER==1234
+  if( (p->nLoaded % 8)==0 && ((aData - (const unsigned char*)0)&7)==0 ){
+    for(; i+7<nData; i+=8){
+      p->u.s[p->nLoaded/8] ^= *(u64*)&aData[i];
+      p->nLoaded += 8;
+      if( p->nLoaded>=p->nRate ){
+        KeccakF1600Step(p);
+        p->nLoaded = 0;
+      }
+    }
+  }
+#endif
+  for(; i<nData; i++){
+#if Hash_BYTEORDER==1234
+    p->u.x[p->nLoaded] ^= aData[i];
+#elif Hash_BYTEORDER==4321
+    p->u.x[p->nLoaded^0x07] ^= aData[i];
+#else
+    p->u.x[p->nLoaded^p->ixMask] ^= aData[i];
+#endif
+    p->nLoaded++;
+    if( p->nLoaded==p->nRate ){
+      KeccakF1600Step(p);
+      p->nLoaded = 0;
+    }
+  }
+}
+
+/*
+** After all content has been added, invoke HashFinal() to compute
+** the final hash.  The function returns a pointer to the binary
+** hash value.
+*/
+static unsigned char *HashFinal(HashContext *p){
+  unsigned int i;
+  if( p->nLoaded==p->nRate-1 ){
+    const unsigned char c1 = 0x86;
+    HashUpdate(p, &c1, 1);
+  }else{
+    const unsigned char c2 = 0x06;
+    const unsigned char c3 = 0x80;
+    HashUpdate(p, &c2, 1);
+    p->nLoaded = p->nRate - 1;
+    HashUpdate(p, &c3, 1);
+  }
+  for(i=0; i<p->nRate; i++){
+    p->u.x[i+p->nRate] = p->u.x[i^p->ixMask];
+  }
+  return &p->u.x[p->nRate];
+}
+
+/*
+** Implementation of the hash(X) function.
+**
+** Return a 160-bit BLOB which is the hash of X.
+*/
+static void hashFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  HashContext cx;
+  int eType = sqlite3_value_type(argv[0]);
+  int nByte = sqlite3_value_bytes(argv[0]);
+  if( eType==SQLITE_NULL ) return;
+  HashInit(&cx, 160);
+  if( eType==SQLITE_BLOB ){
+    HashUpdate(&cx, sqlite3_value_blob(argv[0]), nByte);
+  }else{
+    HashUpdate(&cx, sqlite3_value_text(argv[0]), nByte);
+  }
+  sqlite3_result_blob(context, HashFinal(&cx), 160/8, SQLITE_TRANSIENT);
+}
+
+/* Register the hash function */
+static int hashRegister(sqlite3 *db){
+   return sqlite3_create_function(db, "hash", 1,
+                SQLITE_UTF8 | SQLITE_INNOCUOUS | SQLITE_DETERMINISTIC,
+                0, hashFunc, 0, 0);
+}
+
+/* End of the hashing logic
+*****************************************************************************/
+
+/*
+** Return the tail of a file pathname.  The tail is the last component
+** of the path.  For example, the tail of "/a/b/c.d" is "c.d".
+*/
+const char *file_tail(const char *z){
+  const char *zTail = z;
+  if( !zTail ) return 0;
+  while( z[0] ){
+    if( z[0]=='/' ) zTail = &z[1];
+    z++;
+  }
+  return zTail;
+}
+
+/*
+** Append error message text to the error file, if an error file is
+** specified.  In any case, increment the error count.
+*/
+static void logError(SQLiteRsync *p, const char *zFormat, ...){
+  if( p->zErrFile ){
+    FILE *pErr = fopen(p->zErrFile, "a");
+    if( pErr ){
+      va_list ap;
+      va_start(ap, zFormat);
+      vfprintf(pErr, zFormat, ap);
+      va_end(ap);
+      fclose(pErr);
+    }
+  }
+  p->nErr++;
+}
+
+
+/* Read a single big-endian 32-bit unsigned integer from the input
+** stream.  Return 0 on success and 1 if there are any errors.
+*/
+static int readUint32(SQLiteRsync *p, unsigned int *pU){
+  unsigned char buf[4];
+  if( fread(buf, sizeof(buf), 1, p->pIn)==1 ){
+    *pU = (buf[0]<<24) | (buf[1]<<16) | (buf[2]<<8) | buf[3];
+    p->nIn += 4;
+    return 0;
+  }else{
+    p->nErr++;
+    return 1;
+  }
+}
+
+/* Write a single big-endian 32-bit unsigned integer to the output stream.
+** Return 0 on success and 1 if there are any errors.
+*/
+static int writeUint32(SQLiteRsync *p, unsigned int x){
+  unsigned char buf[4];
+  buf[3] = x & 0xff;
+  x >>= 8;
+  buf[2] = x & 0xff;
+  x >>= 8;
+  buf[1] = x & 0xff;
+  x >>= 8;
+  buf[0] = x;
+  if( p->pLog ) fwrite(buf, sizeof(buf), 1, p->pLog);
+  if( fwrite(buf, sizeof(buf), 1, p->pOut)!=1 ){
+    logError(p, "failed to write 32-bit integer 0x%x", x);
+    return 1;
+  }
+  p->nOut += 4;
+  return 0;
+}
+
+/* Read a single byte from the wire.
+*/
+int readByte(SQLiteRsync *p){
+  int c = fgetc(p->pIn);
+  if( c!=EOF ) p->nIn++;
+  return c;
+}
+
+/* Write a single byte into the wire.
+*/
+void writeByte(SQLiteRsync *p, int c){
+  if( p->pLog ) fputc(c, p->pLog);
+  fputc(c, p->pOut);
+  p->nOut++;
+}
+
+/* Read a power of two encoded as a single byte.
+*/
+int readPow2(SQLiteRsync *p){
+  int x = readByte(p);
+  if( x>=32 ){
+    logError(p, "read invalid page size %d\n", x);
+    return 0;
+  }
+  return 1<<x;
+}
+
+/* Write a power-of-two value onto the wire as a single byte.
+*/
+void writePow2(SQLiteRsync *p, int c){
+  int n;
+  if( c<0 || (c&(c-1))!=0 ){
+    logError(p, "trying to read invalid page size %d\n", c);
+  }
+  for(n=0; c>1; n++){ c /= 2; }
+  writeByte(p, n);
+}
+
+/* Read an array of bytes from the wire.
+*/
+void readBytes(SQLiteRsync *p, int nByte, void *pData){
+  if( fread(pData, 1, nByte, p->pIn)==nByte ){
+    p->nIn += nByte;
+  }else{
+    logError(p, "failed to read %d bytes", nByte);
+  }
+}
+
+/* Write an array of bytes onto the wire.
+*/
+void writeBytes(SQLiteRsync *p, int nByte, const void *pData){
+  if( p->pLog ) fwrite(pData, 1, nByte, p->pLog);
+  if( fwrite(pData, 1, nByte, p->pOut)==nByte ){
+    p->nOut += nByte;
+  }else{
+    logError(p, "failed to write %d bytes", nByte);
+  }
+}
+
+/* Report an error.
+**
+** If this happens on the remote side, we send back a *_ERROR
+** message.  On the local side, the error message goes to stderr.
+*/
+static void reportError(SQLiteRsync *p, const char *zFormat, ...){
+  va_list ap;
+  char *zMsg;
+  unsigned int nMsg;
+  va_start(ap, zFormat);
+  zMsg = sqlite3_vmprintf(zFormat, ap);
+  va_end(ap);
+  nMsg = zMsg ? (unsigned int)strlen(zMsg) : 0;
+  if( p->isRemote ){
+    if( p->isReplica ){
+      putc(REPLICA_ERROR, p->pOut);
+    }else{
+      putc(ORIGIN_ERROR, p->pOut);
+    }
+    writeUint32(p, nMsg);
+    writeBytes(p, nMsg, zMsg);
+    fflush(p->pOut);
+  }else{
+    fprintf(stderr, "%s\n", zMsg);
+  }
+  logError(p, "%s\n", zMsg);
+  sqlite3_free(zMsg);
+}
+
+/* Send an informational message.
+**
+** If this happens on the remote side, we send back a *_MSG 
+** message.  On the local side, the message goes to stdout.
+*/
+static void infoMsg(SQLiteRsync *p, const char *zFormat, ...){
+  va_list ap;
+  char *zMsg;
+  unsigned int nMsg;
+  va_start(ap, zFormat);
+  zMsg = sqlite3_vmprintf(zFormat, ap);
+  va_end(ap);
+  nMsg = zMsg ? (unsigned int)strlen(zMsg) : 0;
+  if( p->isRemote ){
+    if( p->isReplica ){
+      putc(REPLICA_MSG, p->pOut);
+    }else{
+      putc(ORIGIN_MSG, p->pOut);
+    }
+    writeUint32(p, nMsg);
+    writeBytes(p, nMsg, zMsg);
+    fflush(p->pOut);
+  }else{
+    printf("%s\n", zMsg);
+  }
+  sqlite3_free(zMsg);
+}
+
+/* Receive and report an error message coming from the other side.
+*/
+static void readAndDisplayMessage(SQLiteRsync *p, int c){
+  unsigned int n = 0;
+  char *zMsg;
+  const char *zPrefix;
+  if( c==ORIGIN_ERROR || c==REPLICA_ERROR ){
+    zPrefix = "ERROR: ";
+  }else{
+    zPrefix = "";
+  }
+  readUint32(p, &n);
+  if( n==0 ){
+    fprintf(stderr,"ERROR: unknown (possibly out-of-memory)\n");
+  }else{
+    zMsg = sqlite3_malloc64( n+1 );
+    if( zMsg==0 ){
+      fprintf(stderr, "ERROR: out-of-memory\n");
+      return;
+    }
+    memset(zMsg, 0, n+1);
+    readBytes(p, n, zMsg);
+    fprintf(stderr,"%s%s\n", zPrefix, zMsg);
+    if( zPrefix[0] ) logError(p, "%s%s\n", zPrefix, zMsg);
+    sqlite3_free(zMsg);
+  }
+}
+
+/* Construct a new prepared statement.  Report an error and return NULL
+** if anything goes wrong.
+*/
+static sqlite3_stmt *prepareStmtVA(
+  SQLiteRsync *p,
+  char *zFormat,
+  va_list ap
+){
+  sqlite3_stmt *pStmt = 0;
+  char *zSql;
+  char *zToFree = 0;
+  int rc;
+
+  if( strchr(zFormat,'%') ){
+    zSql = sqlite3_vmprintf(zFormat, ap);
+    if( zSql==0 ){
+      reportError(p, "out-of-memory");
+      return 0;
+    }else{
+      zToFree = zSql;
+    }
+  }else{
+    zSql = zFormat;
+  }
+  rc = sqlite3_prepare_v2(p->db, zSql, -1, &pStmt, 0);
+  if( rc || pStmt==0 ){
+    reportError(p, "unable to prepare SQL [%s]: %s", zSql,
+                sqlite3_errmsg(p->db));
+    sqlite3_finalize(pStmt);
+    pStmt = 0;
+  }
+  if( zToFree ) sqlite3_free(zToFree);
+  return pStmt;
+}
+static sqlite3_stmt *prepareStmt(
+  SQLiteRsync *p,
+  char *zFormat,
+  ...
+){
+  sqlite3_stmt *pStmt;
+  va_list ap;
+  va_start(ap, zFormat);
+  pStmt = prepareStmtVA(p, zFormat, ap);
+  va_end(ap);
+  return pStmt;
+}
+
+/* Run a single SQL statement
+*/
+static void runSql(SQLiteRsync *p, char *zSql, ...){
+  sqlite3_stmt *pStmt;
+  va_list ap;
+
+  va_start(ap, zSql);
+  pStmt = prepareStmtVA(p, zSql, ap);
+  va_end(ap);
+  if( pStmt ){
+    int rc = sqlite3_step(pStmt);
+    if( rc==SQLITE_ROW ) rc = sqlite3_step(pStmt);
+    if( rc!=SQLITE_OK && rc!=SQLITE_DONE ){
+      reportError(p, "SQL statement [%s] failed: %s", zSql,
+                  sqlite3_errmsg(p->db));
+    }
+    sqlite3_finalize(pStmt);
+  }
+}
+
+/* Run an SQL statement that returns a single unsigned 32-bit integer result
+*/
+static int runSqlReturnUInt(
+  SQLiteRsync *p,
+  unsigned int *pRes,
+  char *zSql,
+  ...
+){
+  sqlite3_stmt *pStmt;
+  int res = 0;
+  va_list ap;
+
+  va_start(ap, zSql);
+  pStmt = prepareStmtVA(p, zSql, ap);
+  va_end(ap);
+  if( pStmt==0 ){
+    res = 1;
+  }else{
+    int rc = sqlite3_step(pStmt);
+    if( rc==SQLITE_ROW ){
+      *pRes = (unsigned int)(sqlite3_column_int64(pStmt, 0)&0xffffffff);
+    }else{
+      reportError(p, "SQL statement [%s] failed: %s", zSql,
+                  sqlite3_errmsg(p->db));
+      res = 1;
+    }
+    sqlite3_finalize(pStmt);
+  }
+  return res;
+}
+
+/* Run an SQL statement that returns a single TEXT value that is no more
+** than 99 bytes in length.
+*/
+static int runSqlReturnText(
+  SQLiteRsync *p,
+  char *pRes,
+  char *zSql,
+  ...
+){
+  sqlite3_stmt *pStmt;
+  int res = 0;
+  va_list ap;
+
+  va_start(ap, zSql);
+  pStmt = prepareStmtVA(p, zSql, ap);
+  va_end(ap);
+  pRes[0] = 0;
+  if( pStmt==0 ){
+    res = 1;
+  }else{
+    int rc = sqlite3_step(pStmt);
+    if( rc==SQLITE_ROW ){
+      const unsigned char *a = sqlite3_column_text(pStmt, 0);
+      int n;
+      if( a==0 ){
+        pRes[0] = 0;
+      }else{
+        n = sqlite3_column_bytes(pStmt, 0);
+        if( n>99 ) n = 99;
+        memcpy(pRes, a, n);
+        pRes[n] = 0;
+      }
+    }else{
+      reportError(p, "SQL statement [%s] failed: %s", zSql,
+                  sqlite3_errmsg(p->db));
+      res = 1;
+    }
+    sqlite3_finalize(pStmt);
+  }
+  return res;
+}
+
+/* Close the database connection associated with p
+*/
+static void closeDb(SQLiteRsync *p){
+  if( p->db ){
+    sqlite3_close(p->db);
+    p->db = 0;
+  }
+}
+
+/*
+** Run the origin-side protocol.
+**
+** Begin by sending the ORIGIN_BEGIN message with two arguments,
+** nPage, and szPage.  Then enter a loop responding to message from
+** the replica:
+**
+**    REPLICA_ERROR  size  text
+**
+**         Report an error from the replica and quit
+**
+**    REPLICA_END
+**
+**         The replica is terminating.  Stop processing now.
+**
+**    REPLICA_HASH  hash
+**
+**         The argument is the 20-byte SHA1 hash for the next page
+**         page hashes appear in sequential order with no gaps.
+**
+**    REPLICA_READY
+**
+**         The replica has sent all the hashes that it intends to send.
+**         This side (the origin) can now start responding with page
+**         content for pages that do not have a matching hash.
+*/
+static void originSide(SQLiteRsync *p){
+  int rc = 0;
+  int c = 0;
+  unsigned int nPage = 0;
+  unsigned int iPage = 0;
+  unsigned int szPg = 0;
+  sqlite3_stmt *pCkHash = 0;
+  char buf[200];
+
+  p->isReplica = 0;
+  if( p->bCommCheck ){
+    infoMsg(p, "origin  zOrigin=%Q zReplica=%Q isRemote=%d protocol=%d",
+               p->zOrigin, p->zReplica, p->isRemote, PROTOCOL_VERSION);
+    writeByte(p, ORIGIN_END);
+    fflush(p->pOut);
+  }else{
+    /* Open the ORIGIN database. */
+    rc = sqlite3_open_v2(p->zOrigin, &p->db, SQLITE_OPEN_READWRITE, 0);
+    if( rc ){
+      reportError(p, "cannot open origin \"%s\": %s",
+                  p->zOrigin, sqlite3_errmsg(p->db));
+      closeDb(p);
+      return;
+    }
+    hashRegister(p->db);
+    runSql(p, "BEGIN");
+    runSqlReturnText(p, buf, "PRAGMA journal_mode");
+    if( sqlite3_stricmp(buf,"wal")!=0 ){
+      reportError(p, "Origin database is not in WAL mode");
+    }
+    runSqlReturnUInt(p, &nPage, "PRAGMA page_count");
+    runSqlReturnUInt(p, &szPg, "PRAGMA page_size");
+  
+    if( p->nErr==0 ){
+      /* Send the ORIGIN_BEGIN message */
+      writeByte(p, ORIGIN_BEGIN);
+      writeByte(p, PROTOCOL_VERSION);
+      writePow2(p, szPg);
+      writeUint32(p, nPage);
+      fflush(p->pOut);
+      p->nPage = nPage;
+      p->szPage = szPg;
+      p->iProtocol = PROTOCOL_VERSION;
+    }
+  }
+  
+  /* Respond to message from the replica */
+  while( p->nErr==0 && (c = readByte(p))!=EOF && c!=REPLICA_END ){
+    switch( c ){
+      case REPLICA_BEGIN: {
+        /* This message is only sent if the replica received an origin-protocol
+        ** that is larger than what it knows about.  The replica sends back
+        ** a counter-proposal of an earlier protocol which the origin can
+        ** accept by resending a new ORIGIN_BEGIN. */
+        p->iProtocol = readByte(p);
+        writeByte(p, ORIGIN_BEGIN);
+        writeByte(p, p->iProtocol);
+        writePow2(p, p->szPage);
+        writeUint32(p, p->nPage);
+        break;
+      }
+      case REPLICA_MSG:
+      case REPLICA_ERROR: {
+        readAndDisplayMessage(p, c);
+        break;
+      }
+      case REPLICA_HASH: {
+        if( pCkHash==0 ){
+          runSql(p, "CREATE TEMP TABLE badHash(pgno INTEGER PRIMARY KEY)");
+          pCkHash = prepareStmt(p,
+            "INSERT INTO badHash SELECT pgno FROM sqlite_dbpage('main')"
+            " WHERE pgno=?1 AND hash(data)!=?2"
+          );
+          if( pCkHash==0 ) break;
+        }
+        p->nHashSent++;
+        iPage++;
+        sqlite3_bind_int64(pCkHash, 1, iPage);
+        readBytes(p, 20, buf);
+        sqlite3_bind_blob(pCkHash, 2, buf, 20, SQLITE_STATIC);
+        rc = sqlite3_step(pCkHash);
+        if( rc!=SQLITE_DONE ){
+          reportError(p, "SQL statement [%s] failed: %s",
+                      sqlite3_sql(pCkHash), sqlite3_errmsg(p->db));
+        }
+        sqlite3_reset(pCkHash);
+        break;
+      }
+      case REPLICA_READY: {
+        sqlite3_stmt *pStmt;
+        int needPageOne = 0;
+        sqlite3_finalize(pCkHash);
+        pCkHash = 0;
+        if( iPage+1<p->nPage ){
+          runSql(p, "WITH RECURSIVE c(n) AS"
+                    " (VALUES(%d) UNION ALL SELECT n+1 FROM c WHERE n<%d)"
+                    " INSERT INTO badHash SELECT n FROM c",
+                    iPage+1, p->nPage);
+        }
+        pStmt = prepareStmt(p,
+               "SELECT pgno, data"
+               "  FROM badHash JOIN sqlite_dbpage('main') USING(pgno)");
+        if( pStmt==0 ) break;
+        while( sqlite3_step(pStmt)==SQLITE_ROW && p->nErr==0 ){
+          unsigned int pgno = (unsigned int)sqlite3_column_int64(pStmt,0);
+          const void *pContent = sqlite3_column_blob(pStmt, 1);
+          if( pgno==1 ){
+            needPageOne = 1;
+          }else{
+            writeByte(p, ORIGIN_PAGE);
+            writeUint32(p, (unsigned int)sqlite3_column_int64(pStmt, 0));
+            writeBytes(p, szPg, pContent);
+            p->nPageSent++;
+          }
+        }
+        sqlite3_finalize(pStmt);
+        if( needPageOne ){
+          pStmt = prepareStmt(p,
+                 "SELECT data"
+                 "  FROM sqlite_dbpage('main')"
+                 " WHERE pgno=1"
+          );
+          if( pStmt==0 ) break;
+          while( sqlite3_step(pStmt)==SQLITE_ROW && p->nErr==0 ){
+            const void *pContent = sqlite3_column_blob(pStmt, 0);
+            writeByte(p, ORIGIN_PAGE);
+            writeUint32(p, 1);
+            writeBytes(p, szPg, pContent);
+            p->nPageSent++;
+          }
+          sqlite3_finalize(pStmt);
+        }
+        writeByte(p, ORIGIN_TXN);
+        writeUint32(p, nPage);
+        writeByte(p, ORIGIN_END);
+        goto origin_end;
+      }
+      default: {
+        reportError(p, "Unknown message 0x%02x %lld bytes into conversation",
+                       c, p->nIn);
+        break;
+      }
+    }
+  }
+
+origin_end:
+  if( pCkHash ) sqlite3_finalize(pCkHash);
+  closeDb(p);
+}
+
+/*
+** Run the replica-side protocol.  The protocol is passive in the sense
+** that it only response to message from the origin side.
+**
+**    ORIGIN_BEGIN  idProtocol szPage nPage
+**
+**         The origin is reporting the protocol version number, the size of
+**         each page in the origin database (sent as a single-byte power-of-2),
+**         and the number of pages in the origin database.
+**         This procedure checks compatibility, and if everything is ok,
+**         it starts sending hashes of pages already present back to the origin.
+**
+**    ORIGIN_ERROR  size text
+**
+**         Report the received error and quit.
+**
+**    ORIGIN_PAGE  pgno content
+**
+**         Update the content of the given page.
+**
+**    ORIGIN_TXN   pgno
+**
+**         Close the update transaction.  The total database size is pgno
+**         pages.
+**
+**    ORIGIN_END
+**
+**         Expect no more transmissions from the origin.
+*/
+static void replicaSide(SQLiteRsync *p){
+  int c;
+  sqlite3_stmt *pIns = 0;
+  unsigned int szOPage = 0;
+  char buf[65536];
+
+  p->isReplica = 1;
+  if( p->bCommCheck ){
+    infoMsg(p, "replica zOrigin=%Q zReplica=%Q isRemote=%d protocol=%d",
+               p->zOrigin, p->zReplica, p->isRemote, PROTOCOL_VERSION);
+    writeByte(p, REPLICA_END);
+    fflush(p->pOut);
+  }
+
+  /* Respond to message from the origin.  The origin will initiate the
+  ** the conversation with an ORIGIN_BEGIN message.
+  */
+  while( p->nErr==0 && (c = readByte(p))!=EOF && c!=ORIGIN_END ){
+    switch( c ){
+      case ORIGIN_MSG:
+      case ORIGIN_ERROR: {
+        readAndDisplayMessage(p, c);
+        break;
+      }
+      case ORIGIN_BEGIN: {
+        unsigned int nOPage = 0;
+        unsigned int nRPage = 0, szRPage = 0;
+        int rc = 0;
+        sqlite3_stmt *pStmt = 0;
+
+        closeDb(p);
+        p->iProtocol = readByte(p);
+        szOPage = readPow2(p);
+        readUint32(p, &nOPage);
+        if( p->nErr ) break;
+        if( p->iProtocol>PROTOCOL_VERSION ){
+          /* If the protocol version on the origin side is larger, send back
+          ** a REPLICA_BEGIN message with the protocol version number of the
+          ** replica side.  This gives the origin an opportunity to resend
+          ** a new ORIGIN_BEGIN with a reduced protocol version. */
+          writeByte(p, REPLICA_BEGIN);
+          writeByte(p, PROTOCOL_VERSION);
+          break;
+        }
+        p->nPage = nOPage;
+        p->szPage = szOPage;
+        rc = sqlite3_open(p->zReplica, &p->db);
+        if( rc ){
+          reportError(p, "cannot open replica \"%s\": %s",
+                      p->zReplica, sqlite3_errmsg(p->db));
+          closeDb(p);
+          break;
+        }
+        hashRegister(p->db);
+        if( runSqlReturnUInt(p, &nRPage, "PRAGMA page_count") ){
+          break;
+        }
+        if( nRPage==0 ){
+          runSql(p, "PRAGMA page_size=%u", szOPage);
+          runSql(p, "PRAGMA journal_mode=WAL");
+          runSql(p, "SELECT * FROM sqlite_schema");
+        }
+        runSql(p, "BEGIN IMMEDIATE");
+        runSqlReturnText(p, buf, "PRAGMA journal_mode");
+        if( strcmp(buf, "wal")!=0 ){
+          reportError(p, "replica is not in WAL mode");
+          break;
+        }
+        runSqlReturnUInt(p, &nRPage, "PRAGMA page_count");
+        runSqlReturnUInt(p, &szRPage, "PRAGMA page_size");
+        if( szRPage!=szOPage ){
+          reportError(p, "page size mismatch; origin is %d bytes and "
+                         "replica is %d bytes", szOPage, szRPage);
+          break;
+        }
+
+        pStmt = prepareStmt(p,
+                   "SELECT hash(data) FROM sqlite_dbpage"
+                   " WHERE pgno<=min(%d,%d)"
+                   " ORDER BY pgno", nRPage, nOPage);
+        while( sqlite3_step(pStmt)==SQLITE_ROW && p->nErr==0 ){
+          const unsigned char *a = sqlite3_column_blob(pStmt, 0);
+          writeByte(p, REPLICA_HASH);
+          writeBytes(p, 20, a);
+          p->nHashSent++;
+        }
+        sqlite3_finalize(pStmt);
+        writeByte(p, REPLICA_READY);
+        fflush(p->pOut);
+        runSql(p, "PRAGMA writable_schema=ON");
+        break;
+      }
+      case ORIGIN_TXN: {
+        unsigned int nOPage = 0;
+        readUint32(p, &nOPage);
+        if( pIns==0 ){
+          /* Nothing has changed */
+          runSql(p, "COMMIT");
+        }else if( p->nErr ){
+          runSql(p, "ROLLBACK");
+        }else{
+          int rc;
+          sqlite3_bind_int64(pIns, 1, nOPage);
+          sqlite3_bind_null(pIns, 2);
+          rc = sqlite3_step(pIns);
+          if( rc!=SQLITE_DONE ){
+            reportError(p, "SQL statement [%s] failed: %s",
+                   sqlite3_sql(pIns), sqlite3_errmsg(p->db));
+          }
+          sqlite3_reset(pIns);
+          p->nPage = nOPage;
+          runSql(p, "COMMIT");
+        }
+        break;
+      }
+      case ORIGIN_PAGE: {
+        unsigned int pgno = 0;
+        int rc;
+        readUint32(p, &pgno);
+        if( p->nErr ) break;
+        if( pIns==0 ){
+          pIns = prepareStmt(p,
+            "INSERT INTO sqlite_dbpage(pgno,data) VALUES(?1,?2)"
+          );
+          if( pIns==0 ) break;
+        }
+        readBytes(p, szOPage, buf);
+        if( p->nErr ) break;
+        p->nPageSent++;
+        sqlite3_bind_int64(pIns, 1, pgno);
+        sqlite3_bind_blob(pIns, 2, buf, szOPage, SQLITE_STATIC);
+        rc = sqlite3_step(pIns);
+        if( rc!=SQLITE_DONE ){
+          reportError(p, "SQL statement [%s] failed (pgno=%u): %s",
+                 sqlite3_sql(pIns), pgno, sqlite3_errmsg(p->db));
+        }
+        sqlite3_reset(pIns);
+        break;
+      }
+      default: {
+        reportError(p, "Unknown message 0x%02x %lld bytes into conversation",
+                       c, p->nIn);
+        break;
+      }
+    }
+  }
+
+  if( pIns ) sqlite3_finalize(pIns);
+  closeDb(p);
+}
+
+/*
+** The argument might be -vvv...vv with any number of "v"s.  Return
+** the number of "v"s.  Return 0 if the argument is not a -vvv...v.
+*/
+static int numVs(const char *z){
+  int n = 0;
+  if( z[0]!='-' ) return 0;
+  z++;
+  if( z[0]=='-' ) z++;
+  while( z[0]=='v' ){ n++; z++; }
+  if( z[0]==0 ) return n;
+  return 0;
+}
+
+/*
+** Get the argument to an --option.  Throw an error and die if no argument
+** is available.
+*/
+static const char *cmdline_option_value(int argc, const char * const*argv,
+                                        int i){
+  if( i==argc ){
+    fprintf(stderr,"%s: Error: missing argument to %s\n",
+            argv[0], argv[argc-1]);
+    exit(1);
+  }
+  return argv[i];
+}
+
+/*
+** Return the current time in milliseconds since the Julian epoch.
+*/
+sqlite3_int64 currentTime(void){
+  sqlite3_int64 now = 0;
+  sqlite3_vfs *pVfs = sqlite3_vfs_find(0);
+  if( pVfs && pVfs->iVersion>=2 && pVfs->xCurrentTimeInt64!=0 ){
+    pVfs->xCurrentTimeInt64(pVfs, &now);
+  }
+  return now;
+}
+
+/*
+** Parse command-line arguments.  Dispatch subroutines to do the
+** requested work.
+**
+** Input formats:
+**
+**  (1)    sqlite3-rsync  FILENAME1  USER@HOST:FILENAME2
+**
+**  (2)    sqlite3-rsync  USER@HOST:FILENAME1  FILENAME2
+**
+**  (3)    sqlite3-rsync --origin FILENAME1
+**
+**  (4)    sqlite3-rsync --replica FILENAME2
+**
+** The user types (1) or (2).  SSH launches (3) or (4).
+**
+** If (1) is seen then popen2 is used launch (4) on the remote and
+** originSide() is called locally.
+**
+** If (2) is seen, then popen2() is used to launch (3) on the remote
+** and replicaSide() is run locally.
+**
+** If (3) is seen, call originSide() on stdin and stdout.
+**
+q** If (4) is seen, call replicaSide() on stdin and stdout.
+*/
+int main(int argc, char const * const *argv){
+  int isOrigin = 0;
+  int isReplica = 0;
+  int i;
+  SQLiteRsync ctx;
+  char *zDiv;
+  FILE *pIn = 0;
+  FILE *pOut = 0;
+  int childPid = 0;
+  const char *zSsh = "ssh";
+  const char *zExe = "sqlite3-rsync";
+  char *zCmd = 0;
+  sqlite3_int64 tmStart;
+  sqlite3_int64 tmEnd;
+  sqlite3_int64 tmElapse;
+  const char *zRemoteErrFile = 0;
+
+#define cli_opt_val cmdline_option_value(argc, argv, ++i)
+  memset(&ctx, 0, sizeof(ctx));
+  for(i=1; i<argc; i++){
+    const char *z = argv[i];
+    if( strcmp(z,"--origin")==0 ){
+      isOrigin = 1;
+      continue;
+    }
+    if( strcmp(z,"--replica")==0 ){
+      isReplica = 1;
+      continue;
+    }
+    if( numVs(z) ){
+      ctx.eVerbose += numVs(z);
+      continue;
+    }
+    if( strcmp(z, "--ssh")==0 ){
+      zSsh = cli_opt_val;
+      continue;
+    }
+    if( strcmp(z, "--exe")==0 ){
+      zExe = cli_opt_val;
+      continue;
+    }
+    if( strcmp(z, "--logfile")==0 ){
+      /* DEBUG OPTION:  --logfile FILENAME
+      ** Cause all local output traffic to be duplicated in FILENAME */
+      if( ctx.pLog ) fclose(ctx.pLog);
+      ctx.pLog = fopen(argv[++i],"wb");
+      if( ctx.pLog==0 ){
+        fprintf(stderr, "cannot open \"%s\" for writing\n", argv[i]);
+        return 1;
+      }
+      continue;
+    }
+    if( strcmp(z, "--errorfile")==0 ){
+      /* DEBUG OPTION:  --errorfile FILENAME
+      ** Error messages on the local side are written into FILENAME */
+      ctx.zErrFile = argv[++i];
+      continue;
+    }
+    if( strcmp(z, "--remote-errorfile")==0 ){
+      /* DEBUG OPTION:  --remote-errorfile FILENAME
+      ** Error messages on the remote side are written into FILENAME on
+      ** the remote side. */
+      zRemoteErrFile = argv[++i];
+      continue;
+    }
+    if( strcmp(z, "-help")==0 || strcmp(z, "--help")==0
+     || strcmp(z, "-?")==0
+    ){
+      printf("%s", zUsage);
+      return 0;
+    }
+    if( strcmp(z, "--version")==0 ){
+      printf("%s\n", sqlite3_sourceid());
+      return 0;
+    }
+    if( z[0]=='-' ){
+      if( strcmp(z,"--commcheck")==0 ){  /* DEBUG ONLY */
+        /* Run a communication check with the remote side.  Do not attempt
+        ** to exchange any database connection */
+        ctx.bCommCheck = 1;
+        continue;
+      }
+      if( strcmp(z,"--arg-escape-check")==0 ){  /* DEBUG ONLY */
+        /* Test the append_escaped_arg() routine by using it to render a
+        ** copy of the input command-line, assuming all arguments except
+        ** this one are filenames. */
+        sqlite3_str *pStr = sqlite3_str_new(0);
+        int k;
+        for(k=0; k<argc; k++){
+          append_escaped_arg(pStr, argv[k], i!=k);
+        }
+        printf("%s\n", sqlite3_str_value(pStr));
+        return 0;
+      }
+      fprintf(stderr,
+         "unknown option: \"%s\". Use --help for more detail.\n", z);
+      return 1;
+    }
+    if( ctx.zOrigin==0 ){
+      ctx.zOrigin = z;
+    }else if( ctx.zReplica==0 ){
+      ctx.zReplica = z;
+    }else{
+      fprintf(stderr, "Unknown argument: \"%s\"\n", z);
+      return 1;
+    }
+  }
+  if( ctx.zOrigin==0 ){
+    fprintf(stderr, "missing ORIGIN database filename\n");
+    return 1;
+  }
+  if( ctx.zReplica==0 ){
+    fprintf(stderr, "missing REPLICA database filename\n");
+    return 1;
+  }
+  if( isOrigin && isReplica ){
+    fprintf(stderr, "bad option combination\n");
+    return 1;
+  }
+  if( isOrigin ){
+    ctx.pIn = stdin;
+    ctx.pOut = stdout;
+    ctx.isRemote = 1;
+    originSide(&ctx);
+    return 0;
+  }
+  if( isReplica ){
+    ctx.pIn = stdin;
+    ctx.pOut = stdout;
+    ctx.isRemote = 1;
+    replicaSide(&ctx);
+    return 0;
+  }
+  if( ctx.zReplica==0 ){
+    fprintf(stderr, "missing REPLICA database filename\n");
+    return 1;
+  }
+  tmStart = currentTime();
+  zDiv = strchr(ctx.zOrigin,':');
+  if( zDiv ){
+    if( strchr(ctx.zReplica,':')!=0 ){
+      fprintf(stderr,
+         "At least one of ORIGIN and REPLICA must be a local database\n"
+         "You provided two remote databases.\n");
+      return 1;
+    }
+    /* Remote ORIGIN and local REPLICA */
+    sqlite3_str *pStr = sqlite3_str_new(0);
+    append_escaped_arg(pStr, zSsh, 1);
+    sqlite3_str_appendf(pStr, " -e none");
+    *(zDiv++) = 0;
+    append_escaped_arg(pStr, ctx.zOrigin, 0);
+    append_escaped_arg(pStr, zExe, 1);
+    append_escaped_arg(pStr, "--origin", 0);
+    if( ctx.bCommCheck ){
+      append_escaped_arg(pStr, "--commcheck", 0);
+      if( ctx.eVerbose==0 ) ctx.eVerbose = 1;
+    }
+    if( zRemoteErrFile ){
+      append_escaped_arg(pStr, "--errorfile", 0);
+      append_escaped_arg(pStr, zRemoteErrFile, 1);
+    }
+    append_escaped_arg(pStr, zDiv, 1);
+    append_escaped_arg(pStr, file_tail(ctx.zReplica), 1);
+    zCmd = sqlite3_str_finish(pStr);
+    if( ctx.eVerbose>=2 ) printf("%s\n", zCmd);
+    if( popen2(zCmd, &ctx.pIn, &ctx.pOut, &childPid, 0) ){
+      fprintf(stderr, "Could not start auxiliary process: %s\n", zCmd);
+      return 1;
+    }
+    replicaSide(&ctx);
+  }else if( (zDiv = strchr(ctx.zReplica,':'))!=0 ){
+    /* Local ORIGIN and remote REPLICA */
+    sqlite3_str *pStr = sqlite3_str_new(0);
+    append_escaped_arg(pStr, zSsh, 1);
+    sqlite3_str_appendf(pStr, " -e none");
+    *(zDiv++) = 0;
+    append_escaped_arg(pStr, ctx.zReplica, 0);
+    append_escaped_arg(pStr, zExe, 1);
+    append_escaped_arg(pStr, "--replica", 0);
+    if( ctx.bCommCheck ){
+      append_escaped_arg(pStr, "--commcheck", 0);
+      if( ctx.eVerbose==0 ) ctx.eVerbose = 1;
+    }
+    if( zRemoteErrFile ){
+      append_escaped_arg(pStr, "--errorfile", 0);
+      append_escaped_arg(pStr, zRemoteErrFile, 1);
+    }
+    append_escaped_arg(pStr, file_tail(ctx.zOrigin), 1);
+    append_escaped_arg(pStr, zDiv, 1);
+    zCmd = sqlite3_str_finish(pStr);
+    if( ctx.eVerbose>=2 ) printf("%s\n", zCmd);
+    if( popen2(zCmd, &ctx.pIn, &ctx.pOut, &childPid, 0) ){
+      fprintf(stderr, "Could not start auxiliary process: %s\n", zCmd);
+      return 1;
+    }
+    originSide(&ctx);
+  }else{
+    /* Local ORIGIN and REPLICA */
+    sqlite3_str *pStr = sqlite3_str_new(0);
+    append_escaped_arg(pStr, argv[0], 1);
+    append_escaped_arg(pStr, "--replica", 0);
+    if( ctx.bCommCheck ){
+      append_escaped_arg(pStr, "--commcheck", 0);
+    }
+    if( zRemoteErrFile ){
+      append_escaped_arg(pStr, "--errorfile", 0);
+      append_escaped_arg(pStr, zRemoteErrFile, 1);
+    }
+    append_escaped_arg(pStr, ctx.zOrigin, 1);
+    append_escaped_arg(pStr, ctx.zReplica, 1);
+    zCmd = sqlite3_str_finish(pStr);
+    if( ctx.eVerbose>=2 ) printf("%s\n", zCmd);
+    if( popen2(zCmd, &ctx.pIn, &ctx.pOut, &childPid, 0) ){
+      fprintf(stderr, "Could not start auxiliary process: %s\n", zCmd);
+      return 1;
+    }
+    originSide(&ctx);
+  }
+  if( ctx.pLog ) fclose(ctx.pLog);
+  tmEnd = currentTime();
+  tmElapse = tmEnd - tmStart;  /* Elapse time in milliseconds */
+  if( ctx.nErr ){
+    printf("Databases where not synced due to errors\n");
+  }
+  if( ctx.eVerbose>=1 ){
+    char *zMsg;
+    sqlite3_int64 szTotal = (sqlite3_int64)ctx.nPage*(sqlite3_int64)ctx.szPage;
+    sqlite3_int64 nIO = ctx.nOut +ctx.nIn;
+    zMsg = sqlite3_mprintf("sent %,lld bytes, received %,lld bytes",
+                           ctx.nOut, ctx.nIn);
+    printf("%s", zMsg);
+    sqlite3_free(zMsg);
+    if( tmElapse>0 ){
+      zMsg = sqlite3_mprintf(", %,.2f bytes/sec",
+                             1000.0*(double)nIO/(double)tmElapse);
+      printf("%s\n", zMsg);
+      sqlite3_free(zMsg);
+    }else{
+      printf("\n");
+    }
+    if( ctx.nErr==0 ){
+      if( nIO<=szTotal && nIO>0 ){
+        zMsg = sqlite3_mprintf("total size %,lld  speedup is %.2f",
+           szTotal, (double)szTotal/(double)nIO);
+      }else{
+        zMsg = sqlite3_mprintf("total size %,lld", szTotal);
+      }
+      printf("%s\n", zMsg);
+      sqlite3_free(zMsg);
+    }
+  }
+  sqlite3_free(zCmd);
+  if( pIn!=0 && pOut!=0 ){
+    pclose2(pIn, pOut, childPid);
+  }
+  return ctx.nErr;
+}