highperfocused/bitcoin
1
0
Fork 0
mirror of https://github.com/bitcoin/bitcoin.git synced 2025-12-04 01:32:31 +01:00
Code Issues Packages Projects Releases Wiki Activity

Fix bugs on 'unsigned char' platforms.

Browse Source 
In ISO C++, the signedness of 'char' is undefined.  On some platforms (e.g.
ARM), 'char' is an unsigned type, but some of the code relies on 'char' being
signed (as it is on x86).  This is indicated by compiler warnings like this:

 bignum.h: In constructor 'CBigNum::CBigNum(char)':
 bignum.h:81:59: warning: comparison is always true due to limited range of data type [-Wtype-limits]

 util.cpp: In function 'bool IsHex(const string&)':
 util.cpp:427:28: warning: comparison is always false due to limited range of data type [-Wtype-limits]

In particular, IsHex erroneously returned true regardless of the input
characters, as long as the length of the string was a positive multiple of 2.

Note: For testing, it's possible using GCC to force char to be unsigned by
adding the -funsigned-char parameter to xCXXFLAGS.
This commit is contained in:
Dwayne C. Litzenberger
2012-04-16 01:32:55 -04:00
parent a6fa147c8d
commit 8c8e8c2e93
4 changed files with 12 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
src/util.cpp
View File

@@ -425,7 +425,7 @@ bool ParseMoney(const char* pszIn, int64& nRet)
}
static char phexdigit[256] =
static signed char phexdigit[256] =
{ -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
@@ -461,12 +461,12 @@ vector<unsigned char> ParseHex(const char* psz)
{
while (isspace(*psz))
psz++;
char c = phexdigit[(unsigned char)*psz++];
if (c == (char)-1)
signed char c = phexdigit[(unsigned char)*psz++];
if (c == (signed char)-1)
break;
unsigned char n = (c << 4);
c = phexdigit[(unsigned char)*psz++];
if (c == (char)-1)
if (c == (signed char)-1)
break;
n |= c;
vch.push_back(n);