Add streaming version of sqlite3changeset_invert() to sessions module.

FossilOrigin-Name: 8ded6a46794c7bff1c8b790c662ba7e92f576380

ext/session/sqlite3session.c

@@ -334,10 +334,11 @@ static int sessionSerializeValue(
     if( aBuf ) aBuf[0] = '\0';
   }
 
-  *pnWrite += nByte;
+  if( pnWrite ) *pnWrite += nByte;
   return SQLITE_OK;
 }
 
+
 /*
 ** This macro is used to calculate hash key values for data structures. In
 ** order to use this macro, the entire data structure must be represented
@@ -1330,6 +1331,29 @@ static int sessionBufferGrow(SessionBuffer *p, int nByte, int *pRc){
   return (*pRc!=SQLITE_OK);
 }
 
+/*
+** Append the value passed as the second argument to the buffer passed
+** as the first.
+**
+** This function is a no-op if *pRc is non-zero when it is called.
+** Otherwise, if an error occurs, *pRc is set to an SQLite error code
+** before returning.
+*/
+static void sessionAppendValue(SessionBuffer *p, sqlite3_value *pVal, int *pRc){
+  int rc = *pRc;
+  if( rc==SQLITE_OK ){
+    int nByte = 0;
+    sessionSerializeValue(0, pVal, &nByte);
+    sessionBufferGrow(p, nByte, &rc);
+    if( rc==SQLITE_OK ){
+      rc = sessionSerializeValue(&p->aBuf[p->nBuf], pVal, 0);
+      p->nBuf += nByte;
+    }else{
+      *pRc = rc;
+    }
+  }
+}
+
 /*
 ** This function is a no-op if *pRc is other than SQLITE_OK when it is 
 ** called. Otherwise, append a single byte to the buffer. 
@@ -2268,6 +2292,38 @@ static int sessionChangesetBufferTblhdr(SessionInput *pIn, int *pnByte){
   return rc;
 }
 
+/*
+** The input pointer currently points to the first byte of the first field
+** of a record consisting of nCol columns. This function ensures the entire
+** record is buffered.
+*/
+static int sessionChangesetBufferRecord(
+  SessionInput *pIn, 
+  int nCol, 
+  int *pnByte
+){
+  int rc = SQLITE_OK;
+  int nByte = 0;
+  int i;
+  for(i=0; rc==SQLITE_OK && i<nCol; i++){
+    int eType;
+    rc = sessionInputBuffer(pIn, nByte + 10);
+    if( rc==SQLITE_OK ){
+      eType = pIn->aData[pIn->iNext + nByte++];
+      if( eType==SQLITE_TEXT || eType==SQLITE_BLOB ){
+        int n;
+        nByte += sessionVarintGet(&pIn->aData[pIn->iNext+nByte], &n);
+        nByte += n;
+        rc = sessionInputBuffer(pIn, nByte);
+      }else if( eType==SQLITE_INTEGER || eType==SQLITE_FLOAT ){
+        nByte += 8;
+      }
+    }
+  }
+  *pnByte = nByte;
+  return rc;
+}
+
 /*
 ** The input pointer currently points to the second byte of a table-header.
 ** Specifically, to the following:
@@ -2582,44 +2638,37 @@ int sqlite3changeset_finalize(sqlite3_changeset_iter *p){
   return rc;
 }
 
-/*
+static int sessionChangesetInvert(
-** Invert a changeset object.
+  SessionInput *pInput,           /* Input changeset */
-*/
+  int (*xOutput)(void *pOut, const void *pData, int nData),
-int sqlite3changeset_invert(
+  void *pOut,
-  int nChangeset,                 /* Number of bytes in input */
-  const void *pChangeset,         /* Input changeset */
   int *pnInverted,                /* OUT: Number of bytes in output changeset */
   void **ppInverted               /* OUT: Inverse of pChangeset */
 ){
   int rc = SQLITE_OK;             /* Return value */
-  u8 *aOut;
+  SessionBuffer sOut;             /* Output buffer */
-  u8 *aIn;
-  int i;
-  SessionInput sInput;
   int nCol = 0;                   /* Number of cols in current table */
   u8 *abPK = 0;                   /* PK array for current table */
   sqlite3_value **apVal = 0;      /* Space for values for UPDATE inversion */
   SessionBuffer sPK = {0, 0, 0};  /* PK array for current table */
 
+  /* Initialize the output buffer */
+  memset(&sOut, 0, sizeof(SessionBuffer));
+
   /* Zero the output variables in case an error occurs. */
-  *ppInverted = 0;
+  if( ppInverted ){
-  *pnInverted = 0;
+    *ppInverted = 0;
-  if( nChangeset==0 ) return SQLITE_OK;
+    *pnInverted = 0;
+  }
 
-  /* Set up the input stream */
+  while( 1 ){
-  memset(&sInput, 0, sizeof(SessionInput));
-  sInput.nData = nChangeset;
-  sInput.aData = (u8*)pChangeset;
-
-  aOut = (u8 *)sqlite3_malloc(nChangeset);
-  if( !aOut ) return SQLITE_NOMEM;
-  aIn = (u8 *)pChangeset;
-
-  i = 0;
-  while( i<nChangeset ){
     u8 eType;
-    if( (rc = sessionInputBuffer(&sInput, 2)) ) goto finished_invert;
+
-    eType = sInput.aData[sInput.iNext];
+    /* Test for EOF. */
+    if( (rc = sessionInputBuffer(pInput, 2)) ) goto finished_invert;
+    if( pInput->iNext>=pInput->nData ) break;
+    eType = pInput->aData[pInput->iNext];
+
     switch( eType ){
       case 'T': {
         /* A 'table' record consists of:
@@ -2630,19 +2679,19 @@ int sqlite3changeset_invert(
         **   * A nul-terminated table name.
         */
         int nByte;
-        int nVarint;
+        int nVar;
-        int iNext = sInput.iNext;
+        pInput->iNext++;
-        sInput.iNext++;
+        if( (rc = sessionChangesetBufferTblhdr(pInput, &nByte)) ){
-        if( (rc = sessionChangesetBufferTblhdr(&sInput, &nByte)) ){
           goto finished_invert;
         }
-        nVarint = sessionVarintGet(&sInput.aData[iNext+1], &nCol);
+        nVar = sessionVarintGet(&pInput->aData[pInput->iNext], &nCol);
         sPK.nBuf = 0;
-        sessionAppendBlob(&sPK, &sInput.aData[iNext+1+nVarint], nCol, &rc);
+        sessionAppendBlob(&sPK, &pInput->aData[pInput->iNext+nVar], nCol, &rc);
+        sessionAppendByte(&sOut, eType, &rc);
+        sessionAppendBlob(&sOut, &pInput->aData[pInput->iNext], nByte, &rc);
         if( rc ) goto finished_invert;
-        sInput.iNext += nByte;
+
-        memcpy(&aOut[i], &sInput.aData[iNext], nByte+1);
+        pInput->iNext += nByte;
-        i += nByte+1;
         sqlite3_free(apVal);
         apVal = 0;
         abPK = sPK.aBuf;
@@ -2651,22 +2700,22 @@ int sqlite3changeset_invert(
 
       case SQLITE_INSERT:
       case SQLITE_DELETE: {
-        int iStart;
         int nByte;
-        sInput.iNext += 2;
+        int bIndirect = pInput->aData[pInput->iNext+1];
-        iStart = sInput.iNext;
+        int eType2 = (eType==SQLITE_DELETE ? SQLITE_INSERT : SQLITE_DELETE);
-        sessionReadRecord(&sInput, nCol, 0, 0);
+        pInput->iNext += 2;
-        aOut[i] = (eType==SQLITE_DELETE ? SQLITE_INSERT : SQLITE_DELETE);
+        assert( rc==SQLITE_OK );
-        aOut[i+1] = aIn[i+1];               /* indirect-flag */
+        rc = sessionChangesetBufferRecord(pInput, nCol, &nByte);
-        nByte = sInput.iNext - iStart;
+        sessionAppendByte(&sOut, eType2, &rc);
-        memcpy(&aOut[i+2], &sInput.aData[iStart], nByte);
+        sessionAppendByte(&sOut, bIndirect, &rc);
-        i += 2 + nByte;
+        sessionAppendBlob(&sOut, &pInput->aData[pInput->iNext], nByte, &rc);
+        pInput->iNext += nByte;
+        if( rc ) goto finished_invert;
         break;
       }
 
       case SQLITE_UPDATE: {
         int iCol;
-        int nWrite = 0;
 
         if( 0==apVal ){
           apVal = (sqlite3_value **)sqlite3_malloc(sizeof(apVal[0])*nCol*2);
@@ -2678,15 +2727,14 @@ int sqlite3changeset_invert(
         }
 
         /* Write the header for the new UPDATE change. Same as the original. */
-        aOut[i] = SQLITE_UPDATE;
+        sessionAppendByte(&sOut, eType, &rc);
-        aOut[i+1] = sInput.aData[sInput.iNext+1];
+        sessionAppendByte(&sOut, pInput->aData[pInput->iNext+1], &rc);
-        nWrite = 2;
 
         /* Read the old.* and new.* records for the update change. */
-        sInput.iNext += 2;
+        pInput->iNext += 2;
-        rc = sessionReadRecord(&sInput, nCol, 0, &apVal[0]);
+        rc = sessionReadRecord(pInput, nCol, 0, &apVal[0]);
         if( rc==SQLITE_OK ){
-          rc = sessionReadRecord(&sInput, nCol, 0, &apVal[nCol]);
+          rc = sessionReadRecord(pInput, nCol, 0, &apVal[nCol]);
         }
 
         /* Write the new old.* record. Consists of the PK columns from the
@@ -2694,7 +2742,7 @@ int sqlite3changeset_invert(
         ** new.* record. */
         for(iCol=0; rc==SQLITE_OK && iCol<nCol; iCol++){
           sqlite3_value *pVal = apVal[iCol + (abPK[iCol] ? 0 : nCol)];
-          rc = sessionSerializeValue(&aOut[i+nWrite], pVal, &nWrite);
+          sessionAppendValue(&sOut, pVal, &rc);
         }
 
         /* Write the new new.* record. Consists of a copy of all values
@@ -2702,7 +2750,7 @@ int sqlite3changeset_invert(
         ** are set to "undefined". */
         for(iCol=0; rc==SQLITE_OK && iCol<nCol; iCol++){
           sqlite3_value *pVal = (abPK[iCol] ? 0 : apVal[iCol]);
-          rc = sessionSerializeValue(&aOut[i+nWrite], pVal, &nWrite);
+          sessionAppendValue(&sOut, pVal, &rc);
         }
 
         for(iCol=0; iCol<nCol*2; iCol++){
@@ -2713,8 +2761,6 @@ int sqlite3changeset_invert(
           goto finished_invert;
         }
 
-        i += nWrite;
-        assert( i==sInput.iNext );
         break;
       }
 
@@ -2722,21 +2768,73 @@ int sqlite3changeset_invert(
         rc = SQLITE_CORRUPT_BKPT;
         goto finished_invert;
     }
+
+    assert( rc==SQLITE_OK );
+    if( xOutput && sOut.nBuf>=SESSIONS_STR_CHUNK_SIZE ){
+      rc = xOutput(pOut, sOut.aBuf, sOut.nBuf);
+      sOut.nBuf = 0;
+      if( rc!=SQLITE_OK ) goto finished_invert;
+    }
   }
 
   assert( rc==SQLITE_OK );
-  *pnInverted = nChangeset;
+  if( pnInverted ){
-  *ppInverted = (void *)aOut;
+    *pnInverted = sOut.nBuf;
+    *ppInverted = sOut.aBuf;
+    sOut.aBuf = 0;
+  }else if( sOut.nBuf>0 ){
+    rc = xOutput(pOut, sOut.aBuf, sOut.nBuf);
+  }
 
  finished_invert:
-  if( rc!=SQLITE_OK ){
+  sqlite3_free(sOut.aBuf);
-    sqlite3_free(aOut);
-  }
   sqlite3_free(apVal);
   sqlite3_free(sPK.aBuf);
   return rc;
 }
 
+
+/*
+** Invert a changeset object.
+*/
+int sqlite3changeset_invert(
+  int nChangeset,                 /* Number of bytes in input */
+  const void *pChangeset,         /* Input changeset */
+  int *pnInverted,                /* OUT: Number of bytes in output changeset */
+  void **ppInverted               /* OUT: Inverse of pChangeset */
+){
+  SessionInput sInput;
+
+  /* Set up the input stream */
+  memset(&sInput, 0, sizeof(SessionInput));
+  sInput.nData = nChangeset;
+  sInput.aData = (u8*)pChangeset;
+
+  return sessionChangesetInvert(&sInput, 0, 0, pnInverted, ppInverted);
+}
+
+/*
+** Streaming version of sqlite3changeset_invert().
+*/
+int sqlite3changeset_invert_str(
+  int (*xInput)(void *pIn, void *pData, int *pnData),
+  void *pIn,
+  int (*xOutput)(void *pOut, const void *pData, int nData),
+  void *pOut
+){
+  SessionInput sInput;
+  int rc;
+
+  /* Set up the input stream */
+  memset(&sInput, 0, sizeof(SessionInput));
+  sInput.xInput = xInput;
+  sInput.pIn = pIn;
+
+  rc = sessionChangesetInvert(&sInput, xOutput, pOut, 0, 0);
+  sqlite3_free(sInput.buf.aBuf);
+  return rc;
+}
+
 typedef struct SessionApplyCtx SessionApplyCtx;
 struct SessionApplyCtx {
   sqlite3 *db;

ext/session/sqlite3session.h

@@ -670,6 +670,16 @@ int sqlite3changeset_invert(
   int *pnOut, void **ppOut        /* OUT: Inverse of input */
 );
 
+/*
+** Streaming version of sqlite3changeset_invert().
+*/
+int sqlite3changeset_invert_str(
+  int (*xInput)(void *pIn, void *pData, int *pnData),
+  void *pIn,
+  int (*xOutput)(void *pOut, const void *pData, int nData),
+  void *pOut
+);
+
 /*
 ** CAPI3REF: Concatenate Two Changeset Objects
 **

ext/session/test_session.c

@@ -676,24 +676,33 @@ static int test_sqlite3changeset_invert(
   Tcl_Obj *CONST objv[]
 ){
   int rc;                         /* Return code from changeset_invert() */
-  void *aChangeset;               /* Input changeset */
+  TestStreamInput sIn;            /* Input stream */
-  int nChangeset;                 /* Size of buffer aChangeset in bytes */
+  TestSessionsBlob sOut;          /* Output blob */
-  void *aOut;                     /* Output changeset */
-  int nOut;                       /* Size of buffer aOut in bytes */
 
   if( objc!=2 ){
     Tcl_WrongNumArgs(interp, 1, objv, "CHANGESET");
     return TCL_ERROR;
   }
-  aChangeset = (void *)Tcl_GetByteArrayFromObj(objv[1], &nChangeset);
 
-  rc = sqlite3changeset_invert(nChangeset, aChangeset, &nOut, &aOut);
+  memset(&sIn, 0, sizeof(sIn));
-  if( rc!=SQLITE_OK ){
+  memset(&sOut, 0, sizeof(sOut));
-    return test_session_error(interp, rc);
+  sIn.nStream = test_tcl_integer(interp, SESSION_STREAM_TCL_VAR);
+  sIn.aData = Tcl_GetByteArrayFromObj(objv[1], &sIn.nData);
+
+  if( sIn.nStream ){
+    rc = sqlite3changeset_invert_str(
+        testStreamInput, (void*)&sIn, testSessionsOutput, (void*)&sOut
+    );
+  }else{
+    rc = sqlite3changeset_invert(sIn.nData, sIn.aData, &sOut.n, &sOut.p);
   }
-  Tcl_SetObjResult(interp, Tcl_NewByteArrayObj((unsigned char *)aOut, nOut));
+  if( rc!=SQLITE_OK ){
-  sqlite3_free(aOut);
+    rc = test_session_error(interp, rc);
-  return TCL_OK;
+  }else{
+    Tcl_SetObjResult(interp,Tcl_NewByteArrayObj((unsigned char*)sOut.p,sOut.n));
+  }
+  sqlite3_free(sOut.p);
+  return rc;
 }
 
 /*

manifest

@@ -1,5 +1,5 @@
-C Add\sstreaming\sversion\sof\ssqlite3changeset_apply().\sTests\sand\sfixes\sfor\sthe\ssame\sand\ssqlite3changeset_start_str().
+C Add\sstreaming\sversion\sof\ssqlite3changeset_invert()\sto\ssessions\smodule.
-D 2014-09-24T17:13:20.331
+D 2014-09-25T14:54:20.019
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in dd5f245aa8c741bc65845747203c8ce2f3fb6c83
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -158,9 +158,9 @@ F ext/session/sessionA.test eb05c13e4ef1ca8046a3a6dbf2d5f6f5b04a11d4
 F ext/session/sessionB.test 276267cd7fc37c2e2dd03f1e2ed9ada336a8bdb4
 F ext/session/session_common.tcl 1539d8973b2aea0025c133eb0cc4c89fcef541a5
 F ext/session/sessionfault.test e7965159a73d385c1a4af12d82c3a039ebdd71a6
-F ext/session/sqlite3session.c 1c653844900de41e175f77f22fe1af7abb05e798
+F ext/session/sqlite3session.c 9edf9273280c804c45e7508be9644cf96f278c63
-F ext/session/sqlite3session.h 7e7a31ad1992f6678a20654c9751dacd10384292
+F ext/session/sqlite3session.h 944d7b2c3e87b5598a2c34afe8dd032d51d09818
-F ext/session/test_session.c 77f1e7a269daeb60f82441ff859c812d686ef79d
+F ext/session/test_session.c 4449ef150e52baad844aa08c29569f3ec10902d8
 F ext/userauth/sqlite3userauth.h 19cb6f0e31316d0ee4afdfb7a85ef9da3333a220
 F ext/userauth/user-auth.txt e6641021a9210364665fe625d067617d03f27b04
 F ext/userauth/userauth.c 5fa3bdb492f481bbc1709fc83c91ebd13460c69e
@@ -1216,7 +1216,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 0abfd78ceb09b7f7c27c688c8e3fe93268a13b32
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 3c7d3d950bbf5f5ed3696ebc61c77ca48bafe2b5
+P b917fc146876f764442de08d5ec36e5b4cf5ab52
-R bba1026624291c9ce371985c2bc9cae0
+R b1265a84c7bae5ddb87cac377b4def7e
 U dan
-Z 40a11f75418a19b3b02aba54325bf64c
+Z 0bbb9bee98e102db876d83b2977969a7

manifest.uuid

@@ -1 +1 @@
-b917fc146876f764442de08d5ec36e5b4cf5ab52
+8ded6a46794c7bff1c8b790c662ba7e92f576380