Fix a segfault that can occur in matchinfo if an fts4 table contains mostly zero-length documents. Specifically, if the table contains more rows than it does bytes of text.

FossilOrigin-Name: fe9047668eaaf76e7aa1ef1f32dec7c7c4226e45

ext/fts3/fts3_snippet.c

@@ -956,6 +956,7 @@ static int fts3MatchinfoSelectDoctotal(
     if( rc!=SQLITE_OK ) return rc;
   }
   pStmt = *ppStmt;
+  assert( sqlite3_data_count(pStmt)==1 );
 
   a = sqlite3_column_blob(pStmt, 0);
   a += sqlite3Fts3GetVarint(a, &nDoc);

ext/fts3/fts3_write.c

@@ -1104,7 +1104,7 @@ int sqlite3Fts3SegReaderCost(
       sqlite3_stmt *pStmt;
       rc = fts3SqlStmt(p, SQL_SELECT_DOCTOTAL, &pStmt, 0);
       if( rc ) return rc;
-      if( sqlite3_step(pStmt)==SQLITE_ROW ){
+      if( sqlite3_data_count(pStmt) || sqlite3_step(pStmt)==SQLITE_ROW ){
         sqlite3_int64 nDoc = 0;
         sqlite3_int64 nByte = 0;
         const char *a = sqlite3_column_blob(pStmt, 0);
@@ -1116,7 +1116,8 @@ int sqlite3Fts3SegReaderCost(
           }
         }
 
-        pCsr->nRowAvg = (int)(((nByte / nDoc) + pgsz - 1) / pgsz);
+        pCsr->nRowAvg = (int)(((nByte / nDoc) + pgsz) / pgsz);
+        assert( pCsr->nRowAvg>0 ); 
       }
       rc = sqlite3_reset(pStmt);
       if( rc!=SQLITE_OK || pCsr->nRowAvg==0 ) return rc;

manifest

@@ -1,8 +1,5 @@
------BEGIN PGP SIGNED MESSAGE-----
-Hash: SHA1
-
-C Do\snot\sraise\san\sSQLITE_CORRUPT\serror\sin\sRecoverymode\s\nif\sthe\sdatabase\ssize\sin\sthe\sheader\sis\slarger\sthan\sthe\sphysical\sfile\nsize.\s\sThis\sfacilitates\srecovery\sof\sa\sdatabase\sin\swhich\sthe\sdatabase\ssize\nfield\shas\sbeen\scorrupted.
-D 2011-01-12T17:56:26.948
+C Fix\sa\ssegfault\sthat\scan\soccur\sin\smatchinfo\sif\san\sfts4\stable\scontains\smostly\szero-length\sdocuments.\sSpecifically,\sif\sthe\stable\scontains\smore\srows\sthan\sit\sdoes\sbytes\sof\stext.
+D 2011-01-13T10:58:27
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in de6498556d536ae60bb8bb10e8c1ba011448658c
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -72,11 +69,11 @@ F ext/fts3/fts3_hash.c 3c8f6387a4a7f5305588b203fa7c887d753e1f1c
 F ext/fts3/fts3_hash.h 8331fb2206c609f9fc4c4735b9ab5ad6137c88ec
 F ext/fts3/fts3_icu.c ac494aed69835008185299315403044664bda295
 F ext/fts3/fts3_porter.c d61cfd81fb0fd8fbcb25adcaee0ba671aefaa5c2
-F ext/fts3/fts3_snippet.c 3a26a835732619b62f3af1b73f96d017f8651f9f
+F ext/fts3/fts3_snippet.c 196c5e6cde57bfc1907c2d60e9c29590e4f93fb6
 F ext/fts3/fts3_tokenizer.c 055f3dc7369585350b28db1ee0f3b214dca6724d
 F ext/fts3/fts3_tokenizer.h 13ffd9fcb397fec32a05ef5cd9e0fa659bf3dbd3
 F ext/fts3/fts3_tokenizer1.c 6e5cbaa588924ac578263a598e4fb9f5c9bb179d
-F ext/fts3/fts3_write.c 1fd0988538fb3b40009a99068148e63cec7426aa
+F ext/fts3/fts3_write.c 9f3545ae27c13553a6f433fa0ec260fe8bf0cf2f
 F ext/fts3/fts3speed.tcl b54caf6a18d38174f1a6e84219950d85e98bb1e9
 F ext/fts3/mkfts3amal.tcl 252ecb7fe6467854f2aa237bf2c390b74e71f100
 F ext/icu/README.txt bf8461d8cdc6b8f514c080e4e10dc3b2bbdfefa9
@@ -100,7 +97,7 @@ F ext/rtree/rtree_util.tcl 06aab2ed5b826545bf215fff90ecb9255a8647ea
 F ext/rtree/sqlite3rtree.h 1af0899c63a688e272d69d8e746f24e76f10a3f0
 F ext/rtree/tkt3363.test 142ab96eded44a3615ec79fba98c7bde7d0f96de
 F ext/rtree/viewrtree.tcl eea6224b3553599ae665b239bd827e182b466024
-F install-sh 9d4de14ab9fb0facae2f48780b874848cbf2f895 x
+F install-sh 9d4de14ab9fb0facae2f48780b874848cbf2f895
 F ltmain.sh 3ff0879076df340d2e23ae905484d8c15d5fdea8
 F main.mk 05d0f3475dd331896bd607cfb45c5e21b94589ad
 F mkdll.sh 7d09b23c05d56532e9d44a50868eb4b12ff4f74a
@@ -453,7 +450,7 @@ F test/fts3expr.test 5e745b2b6348499d9ef8d59015de3182072c564c
 F test/fts3expr2.test 18da930352e5693eaa163a3eacf96233b7290d1a
 F test/fts3fault.test f83e556465bb69dc8bc676339eca408dce4ca246
 F test/fts3malloc.test 9c8cc3f885bb4dfc66d0460c52f68f45e4710d1b
-F test/fts3matchinfo.test ae910aa666285e14743a80799214bfb3f1aab8f2
+F test/fts3matchinfo.test 32e31467963698cc7fa311e9a61f99d7d06cf72b
 F test/fts3near.test 2e318ee434d32babd27c167142e2b94ddbab4844
 F test/fts3query.test ef79d31fdb355d094baec1c1b24b60439a1fb8a2
 F test/fts3rnd.test 2b1a579be557ab8ac54a51b39caa4aa8043cc4ad
@@ -592,7 +589,7 @@ F test/permutations.test c0ce0f3b741dd92a6d4c2671dbacba4b92dd81eb
 F test/pragma.test fdfc09067ea104a0c247a1a79d8093b56656f850
 F test/pragma2.test 5364893491b9231dd170e3459bfc2e2342658b47
 F test/printf.test 05970cde31b1a9f54bd75af60597be75a5c54fea
-F test/progress.test 5b075c3c790c7b2a61419bc199db87aaf48b8301
+F test/progress.test 5b075c3c790c7b2a61419bc199db87aaf48b8301 x
 F test/ptrchng.test ef1aa72d6cf35a2bbd0869a649b744e9d84977fc
 F test/quick.test 1681febc928d686362d50057c642f77a02c62e57
 F test/quota.test ddafe133653093eb9a99ccd6264884ae43f9c9b8
@@ -873,7 +870,7 @@ F tool/genfkey.test 4196a8928b78f51d54ef58e99e99401ab2f0a7e5
 F tool/lemon.c dfd81a51b6e27e469ba21d01a75ddf092d429027
 F tool/lempar.c 01ca97f87610d1dac6d8cd96ab109ab1130e76dc
 F tool/mkkeywordhash.c d2e6b4a5965e23afb80fbe74bb54648cd371f309
-F tool/mkopts.tcl 66ac10d240cc6e86abd37dc908d50382f84ff46e
+F tool/mkopts.tcl 66ac10d240cc6e86abd37dc908d50382f84ff46e x
 F tool/mkspeedsql.tcl a1a334d288f7adfe6e996f2e712becf076745c97
 F tool/mksqlite3c.tcl e0db70c2c52b0e3d0867ca931229e5b90ffe7837
 F tool/mksqlite3h.tcl d76c226a5e8e1f3b5f6593bcabe5e98b3b1ec9ff
@@ -898,14 +895,7 @@ F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
-P b7d080b8e850bd262f53f29ba4687a62cf76d4ef
-R 3df20cbf1e57e735d0696445d60d0fe8
-U drh
-Z 2ae16dc41b5332856d6b8afad9a17eaa
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-
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-fRWuQnWOMCXleg04aoLM6ng=
-=2nsc
------END PGP SIGNATURE-----
+P 114640d920e16c85de90b19d53c485135875de5b
+R f5eb10b21437fad711a6b9be4e7a8db9
+U dan
+Z a737930e0e8a10b4bde0b31ffbd88e53

manifest.uuid

@@ -1 +1 @@
-114640d920e16c85de90b19d53c485135875de5b
+fe9047668eaaf76e7aa1ef1f32dec7c7c4226e45

test/fts3matchinfo.test

@@ -337,6 +337,32 @@ do_execsql_test 7.4 {
   FROM t10 WHERE t10 MATCH 'record'
 } {blob 20 blob 20}
 
+#-------------------------------------------------------------------------
+# Test a special case - matchinfo('nxa') with many zero length documents. 
+# Special because "x" internally uses a statement used by both "n" and "a". 
+# This was causing a problem at one point in the obscure case where the
+# total number of bytes of data stored in an fts3 table was greater than
+# the number of rows. i.e. when the following query returns true:
+#
+#   SELECT sum(length(content)) < count(*) FROM fts4table;
+#
+do_execsql_test 8.1 {
+  CREATE VIRTUAL TABLE t11 USING fts4;
+  INSERT INTO t11(t11) VALUES('nodesize=24');
+  INSERT INTO t11 VALUES('quitealongstringoftext');
+  INSERT INTO t11 VALUES('anotherquitealongstringoftext');
+  INSERT INTO t11 VALUES('athirdlongstringoftext');
+  INSERT INTO t11 VALUES('andonemoreforgoodluck');
+}
+do_test 8.2 {
+  for {set i 0} {$i < 200} {incr i} {
+    execsql { INSERT INTO t11 VALUES('') }
+  }
+  execsql { INSERT INTO t11(t11) VALUES('optimize') }
+} {}
+do_execsql_test 8.3 {
+  SELECT mit(matchinfo(t11, 'nxa')) FROM t11 WHERE t11 MATCH 'a*'
+} {{204 1 3 3 0} {204 1 3 3 0} {204 1 3 3 0}}
 
 finish_test