1 #define _SNPRINTF_DLLIMPORT __declspec( dllexport ) 2 3 #include <stdarg.h> 4 #include <stdio.h> 5 6 #include <tchar.h> 7 #include <systools/win32/snprintf.h> 8 9 #if defined(_MSC_VER) && (_MSC_VER >= 1400) 10 #pragma warning(disable:4273) // inconsistent dll linkage 11 #endif 12 13 #if (defined(_MSC_VER) && (_MSC_VER < 1300)) || (defined(__MINGW32_VERSION) && ((__MINGW32_MAJOR_VERSION < 3)||((__MINGW32_MAJOR_VERSION == 3)&&(__MINGW32_MINOR_VERSION < 18)))) 14 15 /* The non-debug versions of _vscprintf/_scprintf are just calls 16 to _vsprintf/_sprintf with string buffer pointer set to NULL, 17 requires MSVCRT version 7.0 */ 18 #ifdef __MINGW32__ 19 static int __cdecl _vsctprintf( const TCHAR *format, va_list ap ) 20 #else 21 static int __cdecl _vsctprintf( const _TXCHAR *format, va_list ap ) 22 #endif 23 { 24 FILE *fp = _tfopen( _T("NUL"), _T("wb") ); 25 26 if ( fp ) 27 { 28 int retval = _vftprintf( fp, format, ap ); 29 fclose( fp ); 30 31 return retval; 32 } 33 34 return -1; 35 } 36 #endif 37 38 /* This function retrieves the pointer to the last character of a buffer. 39 That is the pointer to the last character of the buffer that fits 40 completly into that buffer or the position of the terminating zero. 41 42 buffer Pointer to a _TXCHAR buffer to be examined 43 count size of the buffer to be examined 44 45 return The pointer to the last character that fits into the buffer or 46 NULL if count is zero or count is one and the first byte was a 47 leading DBCS character 48 */ 49 50 static _TCHAR *GetLastBufferChar( _TCHAR *buffer, size_t count ) 51 { 52 _TCHAR *last = NULL; 53 _TCHAR *cur = buffer; 54 55 while ( (size_t)(cur - buffer) < count ) 56 { 57 last = cur; 58 59 if ( !*last ) 60 break; 61 62 cur = _tcsinc(last); 63 } 64 65 return last; 66 } 67 68 /* Implementation of snprintf following the ISO/IEC 9899:1999 (ISO C99) standard */ 69 70 _SNPRINTF_DLLIMPORT int __cdecl vsntprintf( _TCHAR *buffer, size_t count, const _TCHAR *format, va_list list ) 71 { 72 int retval; 73 74 /* First of all call the existing non POSIX standard function assuming 75 the buffer size will be large enough */ 76 77 retval = _vsntprintf( buffer, count, format, list ); 78 79 if ( retval < 0 ) 80 { 81 /* If the buffer wasn't large enough ensure that the buffer will be 82 zero terminated */ 83 84 _TCHAR *last = GetLastBufferChar( buffer, count ); 85 if (last ) 86 *last = 0; 87 88 /* Retrieve the count of characters that would have been written 89 if the buffer were large enough */ 90 91 retval = _vsctprintf( format, list ); 92 } 93 else if ( (size_t)retval == count && count ) 94 { 95 /* If the buffer was large enough but not large enough for the trailing 96 zero make the buffer zero terminated */ 97 98 _TCHAR *last = GetLastBufferChar( buffer, count ); 99 if (last ) 100 *last = 0; 101 } 102 103 return retval; 104 } 105 106 /* Implementation of snprintf following the ISO/IEC 9899:1999 (ISO C99) standard */ 107 108 _SNPRINTF_DLLIMPORT int __cdecl sntprintf( _TCHAR *buffer, size_t count, const _TCHAR *format, ... ) 109 { 110 va_list list; 111 int retval; 112 113 va_start( list, format ); 114 retval = vsntprintf( buffer, count, format, list ); 115 va_end( list ); 116 117 return retval; 118 } 119