From ab99f5f837e40a30be249923a5b4247679b9735d Mon Sep 17 00:00:00 2001
From: Luke Ceddia <flukiluke@gmail.com>
Date: Sun, 16 Aug 2015 01:59:46 +1000
Subject: [PATCH] Added overflow checks to the portable version of qb(), and
 corrected some missing negative signs in the other version. Also patched
 func_val to behave properly when parsing integers > UINT64_MAX.

---
 internal/c/common.cpp | 14 +++++++++++---
 internal/c/libqb.cpp  |  6 +++---
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/internal/c/common.cpp b/internal/c/common.cpp
index 340f411e8..9f4e1baab 100644
--- a/internal/c/common.cpp
+++ b/internal/c/common.cpp
@@ -231,7 +231,15 @@ struct img_struct{
 extern void error(int32 error_number); //declare the erorr handler so we can call it if needed.
 
 #ifdef QB64_NOT_X86
-inline int64 qbr(long double f){if (f<0) return(f-0.5f); else return(f+0.5f);}
+inline int64 qbr(long double f){
+  int64 i; int temp=0;
+  if (f<=-9223372036854775808.5) {error(6); return 0;} // if the float is smaller than what an integer 64 could possible hold, toss an overflow error.
+  if (f>=18446744073709551615.5) {error(6); return 0;} // same result if the number is larger than what an integer 64 could possibly hold.
+  if (f>9223372036854775807) {temp=1;f=f-9223372036854775808;} //if it's too large for a signed int64, make it an unsigned int64 and return that value if possible.
+  if (f<0) i=f-0.5f; else i=f+0.5f;
+  if (temp) return i|0x8000000000000000;//+9223372036854775808;
+  return i;
+}
 inline uint64 qbr_longdouble_to_uint64(long double f){if (f<0) return(f-0.5f); else return(f+0.5f);}
 inline int32 qbr_float_to_long(float f){if (f<0) return(f-0.5f); else return(f+0.5f);}
 inline int32 qbr_double_to_long(double f){if (f<0) return(f-0.5f); else return(f+0.5f);}
@@ -240,7 +248,7 @@ inline int32 qbr_double_to_long(double f){if (f<0) return(f-0.5f); else return(f
 #ifdef QB64_MICROSOFT
 inline int64 qbr(long double f){
   int64 i; int temp=0;
-  if (f<=9223372036854775808.5) {error(6); return 0;} // if the float is smaller than what an integer 64 could possible hold, toss an overflow error.
+  if (f<=-9223372036854775808.5) {error(6); return 0;} // if the float is smaller than what an integer 64 could possible hold, toss an overflow error.
   if (f>=18446744073709551615.5) {error(6); return 0;} // same result if the number is larger than what an integer 64 could possibly hold.
   if (f>9223372036854775807) {temp=1;f=f-9223372036854775808;} //if it's too large for a signed int64, make it an unsigned int64 and return that value if possible.
   __asm{
@@ -280,7 +288,7 @@ inline int32 qbr_double_to_long(double f){
 //FLDT=load long double
 inline int64 qbr(long double f){
   int64 i; int temp=0;
-  if (f<=9223372036854775808.5) {error(6); return 0;} // if the float is smaller than what an integer 64 could possible hold, toss an overflow error.
+  if (f<=-9223372036854775808.5) {error(6); return 0;} // if the float is smaller than what an integer 64 could possible hold, toss an overflow error.
   if (f>=18446744073709551615.5) {error(6); return 0;} // same result if the number is larger than what an integer 64 could possibly hold.
   if (f>9223372036854775807) {temp=1;f=f-9223372036854775808;} //if it's too large for a signed int64, make it an unsigned int64 and return that value if possible.
   __asm__ (
diff --git a/internal/c/libqb.cpp b/internal/c/libqb.cpp
index b8c508183..d035c5e70 100644
--- a/internal/c/libqb.cpp
+++ b/internal/c/libqb.cpp
@@ -14015,6 +14015,9 @@ long double func_val(qbs *s){
  finish:;
 
   if (num_significant_digits==0) return 0;
+  //adjust exponent value appropriately
+  //if most_significant_digit_position=1, then no change need occur
+  exponent_value=exponent_value+most_significant_digit_position-1;
 
   if (exponent_value==0){
     if (num_significant_digits==most_significant_digit_position){
@@ -14032,9 +14035,6 @@ long double func_val(qbs *s){
       built_number[i]=significant_digits[i2]; i++;
     }
     built_number[i]=69; i++;//E
-    //adjust exponent value appropriately
-    //if most_significant_digit_position=1, then no change need occur
-    exponent_value=exponent_value+most_significant_digit_position-1;
     //add exponent's value
 #ifdef QB64_WINDOWS
     i2=sprintf((char*)&built_number[i],"%I64i",exponent_value);