Fix the sqlite3_dbpage virtual table so that it can read and write from

any attached database.

FossilOrigin-Name: d4f893e1ae53a0445939ea2920af87d21dd36270494381028b2eaebe5c188f18

diff --git a/manifest b/manifest
index 367a1a1375e6ae0f22673889e3d251c603b224c2..a593818258106c98e8f6545f7dfa684f71f35dad 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Add\stests\scases\sand\sfix\sminor\sissues\sin\sthe\srtreecheck()\sfunction.
-D 2017-10-25T18:17:24.834
+C Fix\sthe\ssqlite3_dbpage\svirtual\stable\sso\sthat\sit\scan\sread\sand\swrite\sfrom\nany\sattached\sdatabase.
+D 2017-10-25T19:18:33.009
 F Makefile.in e016061b23e60ac9ec27c65cb577292b6bde0307ca55abd874ab3487b3b1beb2
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc 37740aba9c4bb359c627eadccf1cfd7be4f5f847078723777ea7763969e533b1
@@ -413,7 +413,7 @@ F src/callback.c 28a8ede982fde4129b828350f78f2c01fe7d12c74d1a0a05d7108ab36f30868
 F src/complete.c a3634ab1e687055cd002e11b8f43eb75c17da23e
 F src/ctime.c ff1be3eed7bdd75aaca61ca8dc848f7c9f850ef2fb9cb56f2734e922a098f9c0
 F src/date.c 48f743d88bbe88f848532d333cca84f26e52a4f217e86f86be7fc1b919c33d74
-F src/dbpage.c c625a0bd605d4cea9a3258b8db49a5474a04976e95a9fe380cdaf74e8eb6736d
+F src/dbpage.c 196a072dffda3ad50bb078da86bb39f1d07cabe4f88e2b12482f4f5ffce73352
 F src/dbstat.c 7a4ba8518b6369ef3600c49cf9c918ad979acba610b2aebef1b656d649b96720
 F src/delete.c 21a5f1812fdb599e9f7afb9f650bdabab60a3afd51d7e94e539c982f647b0023
 F src/expr.c 755caeafc43e3cd31e1d810795712641f6e19f7e7e9575faece4c77381fd8304
@@ -715,7 +715,7 @@ F test/cursorhint2.test 8457e93d97f665f23f97cdbc8477d16e3480331b
 F test/date.test 9b73bbeb1b82d9c1f44dec5cf563bf7da58d2373
 F test/date2.test 74c234bece1b016e94dd4ef9c8cc7a199a8806c0e2291cab7ba64bace6350b10
 F test/dbfuzz.c 73047c920d6210e5912c87cdffd9a1c281d4252e
-F test/dbpage.test 10b9e91d07b0892444fff4578706648e955b5fb260218298f838da74f0d9d211
+F test/dbpage.test ace7a8d2d66b0ad043dacc61d206991184c9916de6862bf4ff165a7906a624af
 F test/dbstatus.test 73149851b3aff14fc6db478e58f9083a66422cf5
 F test/dbstatus2.test e93ab03bfae6d62d4d935f20de928c19ca0ed0ab
 F test/default.test 0cb49b1c315a0d81c81d775e407f66906a2a604d
@@ -1666,7 +1666,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 7d26498063bbc4525976ace698fafcf161d939908f4ffb36d7a4df8fb1bce1fb
-R b18b38b834db7af5e4754d71c435762f
-U dan
-Z f91c79bfd0a67ab59612bc897b82c53b
+P d6130cd226c0ca95e02f0cbabfdc27071acdcf83e0d0cb0eaa47d992479ed9a1
+R de06ad2d264283eba96aba95f64ee6f5
+U drh
+Z 3b4d77a61659a96790923a30bda00b59

diff --git a/manifest.uuid b/manifest.uuid
index cb99ca30c6a9fe5634d346e3d8655e679de19bbc..ce16a7caf02bf690a9310dcda55c40f7ce80ed99 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-d6130cd226c0ca95e02f0cbabfdc27071acdcf83e0d0cb0eaa47d992479ed9a1
\ No newline at end of file
+d4f893e1ae53a0445939ea2920af87d21dd36270494381028b2eaebe5c188f18
\ No newline at end of file

diff --git a/src/dbpage.c b/src/dbpage.c
index d21c5b6df1a505f2883805c91589d57719428deb..54fb5beaa76d5ebdff7e8cd8fa9b379d3984825c 100644 (file)
--- a/src/dbpage.c
+++ b/src/dbpage.c
@@ -42,17 +42,24 @@ struct DbpageCursor {
   sqlite3_vtab_cursor base;       /* Base class.  Must be first */
   int pgno;                       /* Current page number */
   int mxPgno;                     /* Last page to visit on this scan */
+  Pager *pPager;                  /* Pager being read/written */
+  DbPage *pPage1;                 /* Page 1 of the database */
+  int iDb;                        /* Index of database to analyze */
+  int szPage;                     /* Size of each page in bytes */
 };
 
 struct DbpageTable {
   sqlite3_vtab base;              /* Base class.  Must be first */
   sqlite3 *db;                    /* The database */
-  Pager *pPager;                  /* Pager being read/written */
-  int iDb;                        /* Index of database to analyze */
-  int szPage;                     /* Size of each page in bytes */
-  int nPage;                      /* Number of pages in the file */
 };
 
+/* Columns */
+#define DBPAGE_COLUMN_PGNO    0
+#define DBPAGE_COLUMN_DATA    1
+#define DBPAGE_COLUMN_SCHEMA  2
+
+
+
 /*
 ** Connect to or create a dbpagevfs virtual table.
 */
@@ -65,19 +72,7 @@ static int dbpageConnect(
 ){
   DbpageTable *pTab = 0;
   int rc = SQLITE_OK;
-  int iDb;
 
-  if( argc>=4 ){
-    Token nm;
-    sqlite3TokenInit(&nm, (char*)argv[3]);
-    iDb = sqlite3FindDb(db, &nm);
-    if( iDb<0 ){
-      *pzErr = sqlite3_mprintf("no such schema: %s", argv[3]);
-      return SQLITE_ERROR;
-    }
-  }else{
-    iDb = 0;
-  }
   rc = sqlite3_declare_vtab(db, 
           "CREATE TABLE x(pgno INTEGER PRIMARY KEY, data BLOB, schema HIDDEN)");
   if( rc==SQLITE_OK ){
@@ -87,11 +82,8 @@ static int dbpageConnect(
 
   assert( rc==SQLITE_OK || pTab==0 );
   if( rc==SQLITE_OK ){
-    Btree *pBt = db->aDb[iDb].pBt;
     memset(pTab, 0, sizeof(DbpageTable));
     pTab->db = db;
-    pTab->iDb = iDb;
-    pTab->pPager = pBt ? sqlite3BtreePager(pBt) : 0;
   }
 
   *ppVtab = (sqlite3_vtab*)pTab;
@@ -109,24 +101,55 @@ static int dbpageDisconnect(sqlite3_vtab *pVtab){
 /*
 ** idxNum:
 **
-**     0     full table scan
-**     1     pgno=?1
+**     0     schema=main, full table scan
+**     1     schema=main, pgno=?1
+**     2     schema=?1, full table scan
+**     3     schema=?1, pgno=?2
 */
 static int dbpageBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
   int i;
-  pIdxInfo->estimatedCost = 1.0e6;  /* Initial cost estimate */
+  int iPlan = 0;
+
+  /* If there is a schema= constraint, it must be honored.  Report a
+  ** ridiculously large estimated cost if the schema= constraint is
+  ** unavailable
+  */
+  for(i=0; i<pIdxInfo->nConstraint; i++){
+    struct sqlite3_index_constraint *p = &pIdxInfo->aConstraint[i];
+    if( p->iColumn!=DBPAGE_COLUMN_SCHEMA ) continue;
+    if( p->op!=SQLITE_INDEX_CONSTRAINT_EQ ) continue;
+    if( !p->usable ){
+      /* No solution.  Use the default SQLITE_BIG_DBL cost */
+      pIdxInfo->estimatedRows = 0x7fffffff;
+      return SQLITE_OK;
+    }
+    iPlan = 2;
+    pIdxInfo->aConstraintUsage[i].argvIndex = 1;
+    pIdxInfo->aConstraintUsage[i].omit = 1;
+    break;
+  }
+
+  /* If we reach this point, it means that either there is no schema=
+  ** constraint (in which case we use the "main" schema) or else the
+  ** schema constraint was accepted.  Lower the estimated cost accordingly
+  */
+  pIdxInfo->estimatedCost = 1.0e6;
+
+  /* Check for constraints against pgno */
   for(i=0; i<pIdxInfo->nConstraint; i++){
     struct sqlite3_index_constraint *p = &pIdxInfo->aConstraint[i];
     if( p->usable && p->iColumn<=0 && p->op==SQLITE_INDEX_CONSTRAINT_EQ ){
       pIdxInfo->estimatedRows = 1;
       pIdxInfo->idxFlags = SQLITE_INDEX_SCAN_UNIQUE;
       pIdxInfo->estimatedCost = 1.0;
-      pIdxInfo->idxNum = 1;
-      pIdxInfo->aConstraintUsage[i].argvIndex = 1;
+      pIdxInfo->aConstraintUsage[i].argvIndex = iPlan ? 2 : 1;
       pIdxInfo->aConstraintUsage[i].omit = 1;
+      iPlan |= 1;
       break;
     }
   }
+  pIdxInfo->idxNum = iPlan;
+
   if( pIdxInfo->nOrderBy>=1
    && pIdxInfo->aOrderBy[0].iColumn<=0
    && pIdxInfo->aOrderBy[0].desc==0
@@ -160,6 +183,7 @@ static int dbpageOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
 */
 static int dbpageClose(sqlite3_vtab_cursor *pCursor){
   DbpageCursor *pCsr = (DbpageCursor *)pCursor;
+  if( pCsr->pPage1 ) sqlite3PagerUnrefPageOne(pCsr->pPage1);
   sqlite3_free(pCsr);
   return SQLITE_OK;
 }
@@ -179,6 +203,16 @@ static int dbpageEof(sqlite3_vtab_cursor *pCursor){
   return pCsr->pgno > pCsr->mxPgno;
 }
 
+/*
+** idxNum:
+**
+**     0     schema=main, full table scan
+**     1     schema=main, pgno=?1
+**     2     schema=?1, full table scan
+**     3     schema=?1, pgno=?2
+**
+** idxStr is not used
+*/
 static int dbpageFilter(
   sqlite3_vtab_cursor *pCursor, 
   int idxNum, const char *idxStr,
@@ -187,22 +221,40 @@ static int dbpageFilter(
   DbpageCursor *pCsr = (DbpageCursor *)pCursor;
   DbpageTable *pTab = (DbpageTable *)pCursor->pVtab;
   int rc = SQLITE_OK;
-  Btree *pBt = pTab->db->aDb[pTab->iDb].pBt;
+  sqlite3 *db = pTab->db;
+  Btree *pBt;
+
+  /* Default setting is no rows of result */
+  pCsr->pgno = 1; 
+  pCsr->mxPgno = 0;
 
-  pTab->szPage = sqlite3BtreeGetPageSize(pBt);
-  pTab->nPage = sqlite3BtreeLastPage(pBt);
-  if( idxNum==1 ){
-    pCsr->pgno = sqlite3_value_int(argv[0]);
-    if( pCsr->pgno<1 || pCsr->pgno>pTab->nPage ){
+  if( idxNum & 2 ){
+    const char *zSchema;
+    assert( argc>=1 );
+    zSchema = (const char*)sqlite3_value_text(argv[0]);
+    pCsr->iDb = sqlite3FindDbName(db, zSchema);
+    if( pCsr->iDb<0 ) return SQLITE_OK;
+  }else{
+    pCsr->iDb = 0;
+  }
+  pBt = db->aDb[pCsr->iDb].pBt;
+  if( pBt==0 ) return SQLITE_OK;
+  pCsr->pPager = sqlite3BtreePager(pBt);
+  pCsr->szPage = sqlite3BtreeGetPageSize(pBt);
+  pCsr->mxPgno = sqlite3BtreeLastPage(pBt);
+  if( idxNum & 1 ){
+    assert( argc>(idxNum>>1) );
+    pCsr->pgno = sqlite3_value_int(argv[idxNum>>1]);
+    if( pCsr->pgno<1 || pCsr->pgno>pCsr->mxPgno ){
       pCsr->pgno = 1;
       pCsr->mxPgno = 0;
     }else{
       pCsr->mxPgno = pCsr->pgno;
     }
   }else{
-    pCsr->pgno = 1;
-    pCsr->mxPgno = pTab->nPage;
+    assert( pCsr->pgno==1 );
   }
+  rc = sqlite3PagerGet(pCsr->pPager, 1, &pCsr->pPage1, 0);
   return rc;
 }
 
@@ -212,7 +264,6 @@ static int dbpageColumn(
   int i
 ){
   DbpageCursor *pCsr = (DbpageCursor *)pCursor;
-  DbpageTable *pTab = (DbpageTable *)pCursor->pVtab;
   int rc = SQLITE_OK;
   switch( i ){
     case 0: {           /* pgno */
@@ -221,9 +272,9 @@ static int dbpageColumn(
     }
     case 1: {           /* data */
       DbPage *pDbPage = 0;
-      rc = sqlite3PagerGet(pTab->pPager, pCsr->pgno, (DbPage**)&pDbPage, 0);
+      rc = sqlite3PagerGet(pCsr->pPager, pCsr->pgno, (DbPage**)&pDbPage, 0);
       if( rc==SQLITE_OK ){
-        sqlite3_result_blob(ctx, sqlite3PagerGetData(pDbPage), pTab->szPage,
+        sqlite3_result_blob(ctx, sqlite3PagerGetData(pDbPage), pCsr->szPage,
                             SQLITE_TRANSIENT);
       }
       sqlite3PagerUnref(pDbPage);
@@ -231,7 +282,7 @@ static int dbpageColumn(
     }
     default: {          /* schema */
       sqlite3 *db = sqlite3_context_db_handle(ctx);
-      sqlite3_result_text(ctx, db->aDb[pTab->iDb].zDbSName, -1, SQLITE_STATIC);
+      sqlite3_result_text(ctx, db->aDb[pCsr->iDb].zDbSName, -1, SQLITE_STATIC);
       break;
     }
   }
@@ -255,33 +306,47 @@ static int dbpageUpdate(
   DbPage *pDbPage = 0;
   int rc = SQLITE_OK;
   char *zErr = 0;
+  const char *zSchema;
+  int iDb;
+  Btree *pBt;
+  Pager *pPager;
+  int szPage;
 
   if( argc==1 ){
     zErr = "cannot delete";
     goto update_fail;
   }
   pgno = sqlite3_value_int(argv[0]);
-  if( pgno<1 || pgno>pTab->nPage ){
-    zErr = "bad page number";
-    goto update_fail;
-  }
   if( sqlite3_value_int(argv[1])!=pgno ){
     zErr = "cannot insert";
     goto update_fail;
   }
+  zSchema = (const char*)sqlite3_value_text(argv[4]);
+  iDb = zSchema ? sqlite3FindDbName(pTab->db, zSchema) : -1;
+  if( iDb<0 ){
+    zErr = "no such schema";
+    goto update_fail;
+  }
+  pBt = pTab->db->aDb[iDb].pBt;
+  if( pgno<1 || pBt==0 || pgno>sqlite3BtreeLastPage(pBt) ){
+    zErr = "bad page number";
+    goto update_fail;
+  }
+  szPage = sqlite3BtreeGetPageSize(pBt);
   if( sqlite3_value_type(argv[3])!=SQLITE_BLOB 
-   || sqlite3_value_bytes(argv[3])!=pTab->szPage 
+   || sqlite3_value_bytes(argv[3])!=szPage
   ){
     zErr = "bad page value";
     goto update_fail;
   }
-  rc = sqlite3PagerGet(pTab->pPager, pgno, (DbPage**)&pDbPage, 0);
+  pPager = sqlite3BtreePager(pBt);
+  rc = sqlite3PagerGet(pPager, pgno, (DbPage**)&pDbPage, 0);
   if( rc==SQLITE_OK ){
     rc = sqlite3PagerWrite(pDbPage);
     if( rc==SQLITE_OK ){
       memcpy(sqlite3PagerGetData(pDbPage),
              sqlite3_value_blob(argv[3]),
-             pTab->szPage);
+             szPage);
     }
   }
   sqlite3PagerUnref(pDbPage);
@@ -293,6 +358,22 @@ update_fail:
   return SQLITE_ERROR;
 }
 
+/* Since we do not know in advance which database files will be
+** written by the sqlite_dbpage virtual table, start a write transaction
+** on them all.
+*/
+static int dbpageBegin(sqlite3_vtab *pVtab){
+  DbpageTable *pTab = (DbpageTable *)pVtab;
+  sqlite3 *db = pTab->db;
+  int i;
+  for(i=0; i<db->nDb; i++){
+    Btree *pBt = db->aDb[i].pBt;
+    if( pBt ) sqlite3BtreeBeginTrans(pBt, 1);
+  }
+  return SQLITE_OK;
+}
+
+
 /*
 ** Invoke this routine to register the "dbpage" virtual table module
 */
@@ -312,7 +393,7 @@ int sqlite3DbpageRegister(sqlite3 *db){
     dbpageColumn,                 /* xColumn - read data */
     dbpageRowid,                  /* xRowid - read data */
     dbpageUpdate,                 /* xUpdate */
-    0,                            /* xBegin */
+    dbpageBegin,                  /* xBegin */
     0,                            /* xSync */
     0,                            /* xCommit */
     0,                            /* xRollback */

diff --git a/test/dbpage.test b/test/dbpage.test
index a8ef8c0800bd8ecd71799398ae718dda0acd94cc..5a68d3cabaa8af795735364d70f7f72e1fa5fe7a 100644 (file)
--- a/test/dbpage.test
+++ b/test/dbpage.test
@@ -49,6 +49,13 @@ do_execsql_test 140 {
 do_execsql_test 150 {
   SELECT pgno, quote(substr(data,1,5)) FROM sqlite_dbpage WHERE pgno=0;
 } {}
+do_execsql_test 160 {
+  ATTACH ':memory:' AS aux1;
+  PRAGMA aux1.page_size=4096;
+  CREATE TABLE aux1.t2(a,b,c);
+  INSERT INTO t2 VALUES(11,12,13);
+  SELECT pgno, quote(substr(data,1,5)) FROM sqlite_dbpage('aux1');
+} {1 X'53514C6974' 2 X'0D00000001'}
 
 do_execsql_test 200 {
   CREATE TEMP TABLE saved_content(x);
@@ -67,8 +74,23 @@ do_execsql_test 230 {
 do_catchsql_test 230 {
   PRAGMA integrity_check;
 } {0 ok}
-
-
-
+do_execsql_test 240 {
+  DELETE FROM saved_content;
+  INSERT INTO saved_content(x) 
+     SELECT data FROM sqlite_dbpage WHERE schema='aux1' AND pgno=2;
+} {}
+do_execsql_test 241 {
+  UPDATE sqlite_dbpage SET data=zeroblob(4096) WHERE pgno=2 AND schema='aux1';
+} {}
+do_catchsql_test 250 {
+  PRAGMA aux1.integrity_check;
+} {1 {database disk image is malformed}}
+do_execsql_test 260 {
+  UPDATE sqlite_dbpage SET data=(SELECT x FROM saved_content)
+   WHERE pgno=2 AND schema='aux1';
+} {}
+do_catchsql_test 270 {
+  PRAGMA aux1.integrity_check;
+} {0 ok}
 
 finish_test