libsex/utility.cxx

   1 /**
   2  * @file
   3  *
   4  * Non-template definitions of formatting-related internal
   5  * functions.
   6  */
   7
   8 #include <libsex/utility.hxx>
   9 #include <cassert>
  10
  11 bool libsex::vformat(
  12         char* const buf,
  13         size_t len,
  14         const char* const file,
  15         unsigned short line,
  16         const char* const msg,
  17         va_list ap) throw()
  18 {
  19         size_t chars = snprintf(buf, len, "%s:%d: ", file, line);
  20
  21         // If buffer was too small, chars contains length
  22         // of chars that would've been written. Chars must
  23         // be lower than length or else we could not fit
  24         // the message into buffer, too.
  25         bool didFitIntoBuffer = chars < len;
  26
  27         if (didFitIntoBuffer) {
  28                 size_t      newLength = len - chars;
  29                 char* const newBuffer = buf + chars;
  30                 chars = vsnprintf(newBuffer, newLength, msg, ap);
  31                 didFitIntoBuffer = chars <= newLength;
  32         }
  33
  34         return didFitIntoBuffer;
  35 }
  36
  37 bool libsex::format(
  38         char* const buf,
  39         size_t len,
  40         const char* const file,
  41         unsigned short line,
  42         const char* const msg,
  43         ...) throw()
  44 {
  45         va_list ap;
  46         va_start(ap, msg);
  47
  48         bool result = vformat(buf, len, file, line, msg, ap);
  49
  50         va_end(ap);
  51         return result;
  52 }