/*
** The implementation of the sqlite_record() function. This function accepts
** a single argument of any type. The return value is a formatted database
** record (a blob) containing the argument value.
**
** This is used to convert the value stored in the 'sample' column of the
** sqlite_stat3 table to the record format SQLite uses internally.
*/
static void recordFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
const int file_format = 1;
int iSerial; /* Serial type */
int nSerial; /* Bytes of space for iSerial as varint */
int nVal; /* Bytes of space required for argv[0] */
int nRet;
sqlite3 *db;
u8 *aRet;
UNUSED_PARAMETER( argc );
iSerial = sqlite3VdbeSerialType(argv[0], file_format);
nSerial = sqlite3VarintLen(iSerial);
nVal = sqlite3VdbeSerialTypeLen(iSerial);
db = sqlite3_context_db_handle(context);
nRet = 1 + nSerial + nVal;
aRet = sqlite3DbMallocRaw(db, nRet);
if( aRet==0 ){
sqlite3_result_error_nomem(context);
}else{
aRet[0] = nSerial+1;
sqlite3PutVarint(&aRet[1], iSerial);
sqlite3VdbeSerialPut(&aRet[1+nSerial], nVal, argv[0], file_format);
sqlite3_result_blob(context, aRet, nRet, SQLITE_TRANSIENT);
sqlite3DbFree(db, aRet);
}
}
/*
** Write a single varint, value iVal, to file-descriptor pFile. Return
** SQLITE_OK if successful, or an SQLite error code if some error occurs.
**
** The value of *piOffset when this function is called is used as the byte
** offset in file pFile to write to. Before returning, *piOffset is
** incremented by the number of bytes written.
*/
static int vdbeSorterWriteVarint(
sqlite3_file *pFile, /* File to write to */
i64 iVal, /* Value to write as a varint */
i64 *piOffset /* IN/OUT: Write offset in file pFile */
){
u8 aVarint[9]; /* Buffer large enough for a varint */
int nVarint; /* Number of used bytes in varint */
int rc; /* Result of write() call */
nVarint = sqlite3PutVarint(aVarint, iVal);
rc = sqlite3OsWrite(pFile, aVarint, nVarint, *piOffset);
*piOffset += nVarint;
return rc;
}
/*
** Write value iVal encoded as a varint to the file-write object. Return
** SQLITE_OK if successful, or an SQLite error code if an error occurs.
*/
static void fileWriterWriteVarint(FileWriter *p, u64 iVal){
int nByte;
u8 aByte[10];
nByte = sqlite3PutVarint(aByte, iVal);
fileWriterWrite(p, aByte, nByte);
}