Improved rounding policy.

FossilOrigin-Name: 6f1122e942b8269552daaf13d647d200d8546ec25f36310d67037c6b58d09976

4 files changed, 7 insertions, 6 deletions

diff --git a/src/func.c b/src/func.c
index b24359186..07ada2ef6 100644
--- a/src/func.c
+++ b/src/func.c
@@ -461,7 +461,7 @@ static void roundFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
   }else if( n==0 ){ 
     r = (double)((sqlite_int64)(r+(r<0?-0.5:+0.5)));
   }else{
-    zBuf = sqlite3_mprintf("%.*f",n,r);
+    zBuf = sqlite3_mprintf("%!.*f",n,r);
     if( zBuf==0 ){
       sqlite3_result_error_nomem(context);
       return;
diff --git a/src/printf.c b/src/printf.c
index 4de06c116..f00ad4cb2 100644
--- a/src/printf.c
+++ b/src/printf.c
@@ -502,7 +502,7 @@ void sqlite3_str_vappendf(
         }else{
           iRound = precision+1;
         }
-        sqlite3FpDecode(&s, realvalue, iRound);
+        sqlite3FpDecode(&s, realvalue, iRound, flag_altform2 ? 26 : 16);
         if( s.isSpecial ){
           if( s.isSpecial==2 ){
             bufpt = flag_zeropad ? "null" : "NaN";
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 011a44bcb..5662ab4fd 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -4610,7 +4610,7 @@ struct FpDecode {
   char z[24];          /* Significiant digits */
 };
 
-void sqlite3FpDecode(FpDecode*,double,int);
+void sqlite3FpDecode(FpDecode*,double,int,int);
 char *sqlite3MPrintf(sqlite3*,const char*, ...);
 char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
 #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE)
diff --git a/src/util.c b/src/util.c
index 0950d8427..41359ea2a 100644
--- a/src/util.c
+++ b/src/util.c
@@ -937,7 +937,7 @@ int sqlite3Atoi(const char *z){
 ** decimal point if n is negative.  No rounding is performed if
 ** n is zero.
 */
-void sqlite3FpDecode(FpDecode *p, double r, int iRound){
+void sqlite3FpDecode(FpDecode *p, double r, int iRound, int mxRound){
   int i;
   u64 v;
   int e, exp = 0;
@@ -972,7 +972,7 @@ void sqlite3FpDecode(FpDecode *p, double r, int iRound){
     while( r>=1.0e+119 ){ exp+=100; r /= 1.0e+100; }
     while( r>=1.0e+29  ){ exp+=10;  r /= 1.0e+10;  }
     while( r>=1.0e+19  ){ exp++;    r /= 10.0;     }
-  }else if( r<1.0e+17 ){
+  }else{
     while( r<1.0e-97   ){ exp-=100; r *= 1.0e+100; }
     while( r<1.0e+07   ){ exp-=10;  r *= 1.0e+10;  }
     while( r<1.0e+17   ){ exp--;    r *= 10.0;     }
@@ -991,8 +991,9 @@ void sqlite3FpDecode(FpDecode *p, double r, int iRound){
       p->iDP++;
     }
   }
-  if( iRound>0 && iRound<p->n ){
+  if( iRound>0 && (iRound<p->n || p->n>mxRound) ){
     char *z = &p->z[i+1];
+    if( iRound>mxRound ) iRound = mxRound;
     p->n = iRound;
     if( z[iRound]>='5' ){
       int j = iRound-1;