+ va_list argptr;
+ va_start(argptr, format);
+
+ wxString s;
+ s.PrintfV(format, argptr);
+
+ va_end(argptr);
+
+ return s;
+}
+#endif // wxUSE_UNICODE_UTF8
+
+/* static */
+wxString wxString::FormatV(const wxString& format, va_list argptr)
+{
+ wxString s;
+ s.PrintfV(format, argptr);
+ return s;
+}
+
+#if !wxUSE_UTF8_LOCALE_ONLY
+#ifdef wxNEEDS_WXSTRING_PRINTF_MIXIN
+int wxStringPrintfMixinBase::DoPrintfWchar(const wxChar *format, ...)
+#else
+int wxString::DoPrintfWchar(const wxChar *format, ...)
+#endif
+{
+ va_list argptr;
+ va_start(argptr, format);
+
+#ifdef wxNEEDS_WXSTRING_PRINTF_MIXIN
+ // get a pointer to the wxString instance; we have to use dynamic_cast<>
+ // because it's the only cast that works safely for downcasting when
+ // multiple inheritance is used:
+ wxString *str = static_cast<wxString*>(this);
+#else
+ wxString *str = this;
+#endif
+
+ int iLen = str->PrintfV(format, argptr);
+
+ va_end(argptr);
+
+ return iLen;
+}
+#endif // !wxUSE_UTF8_LOCALE_ONLY
+
+#if wxUSE_UNICODE_UTF8
+int wxString::DoPrintfUtf8(const char *format, ...)
+{
+ va_list argptr;
+ va_start(argptr, format);
+
+ int iLen = PrintfV(format, argptr);
+
+ va_end(argptr);
+
+ return iLen;
+}
+#endif // wxUSE_UNICODE_UTF8
+
+/*
+ Uses wxVsnprintf and places the result into the this string.
+
+ In ANSI build, wxVsnprintf is effectively vsnprintf but in Unicode build
+ it is vswprintf. Due to a discrepancy between vsnprintf and vswprintf in
+ the ISO C99 (and thus SUSv3) standard the return value for the case of
+ an undersized buffer is inconsistent. For conforming vsnprintf
+ implementations the function must return the number of characters that
+ would have been printed had the buffer been large enough. For conforming
+ vswprintf implementations the function must return a negative number
+ and set errno.
+
+ What vswprintf sets errno to is undefined but Darwin seems to set it to
+ EOVERFLOW. The only expected errno are EILSEQ and EINVAL. Both of
+ those are defined in the standard and backed up by several conformance
+ statements. Note that ENOMEM mentioned in the manual page does not
+ apply to swprintf, only wprintf and fwprintf.
+
+ Official manual page:
+ http://www.opengroup.org/onlinepubs/009695399/functions/swprintf.html
+
+ Some conformance statements (AIX, Solaris):
+ http://www.opengroup.org/csq/view.mhtml?RID=ibm%2FSD1%2F3
+ http://www.theopengroup.org/csq/view.mhtml?norationale=1&noreferences=1&RID=Fujitsu%2FSE2%2F10
+
+ Since EILSEQ and EINVAL are rather common but EOVERFLOW is not and since
+ EILSEQ and EINVAL are specifically defined to mean the error is other than
+ an undersized buffer and no other errno are defined we treat those two
+ as meaning hard errors and everything else gets the old behavior which
+ is to keep looping and increasing buffer size until the function succeeds.
+
+ In practice it's impossible to determine before compilation which behavior
+ may be used. The vswprintf function may have vsnprintf-like behavior or
+ vice-versa. Behavior detected on one release can theoretically change
+ with an updated release. Not to mention that configure testing for it
+ would require the test to be run on the host system, not the build system
+ which makes cross compilation difficult. Therefore, we make no assumptions
+ about behavior and try our best to handle every known case, including the
+ case where wxVsnprintf returns a negative number and fails to set errno.
+
+ There is yet one more non-standard implementation and that is our own.
+ Fortunately, that can be detected at compile-time.
+
+ On top of all that, ISO C99 explicitly defines snprintf to write a null
+ character to the last position of the specified buffer. That would be at
+ at the given buffer size minus 1. It is supposed to do this even if it
+ turns out that the buffer is sized too small.
+
+ Darwin (tested on 10.5) follows the C99 behavior exactly.
+
+ Glibc 2.6 almost follows the C99 behavior except vswprintf never sets
+ errno even when it fails. However, it only seems to ever fail due
+ to an undersized buffer.
+*/
+#if wxUSE_UNICODE_UTF8
+template<typename BufferType>
+#else
+// we only need one version in non-UTF8 builds and at least two Windows
+// compilers have problems with this function template, so use just one
+// normal function here
+#endif
+static int DoStringPrintfV(wxString& str,
+ const wxString& format, va_list argptr)
+{
+ int size = 1024;
+
+ for ( ;; )
+ {
+#if wxUSE_UNICODE_UTF8
+ BufferType tmp(str, size + 1);
+ typename BufferType::CharType *buf = tmp;
+#else
+ wxStringBuffer tmp(str, size + 1);
+ wxChar *buf = tmp;
+#endif
+
+ if ( !buf )
+ {
+ // out of memory
+
+ // in UTF-8 build, leaving uninitialized junk in the buffer
+ // could result in invalid non-empty UTF-8 string, so just
+ // reset the string to empty on failure:
+ buf[0] = '\0';
+ return -1;
+ }
+
+ // wxVsnprintf() may modify the original arg pointer, so pass it
+ // only a copy
+ va_list argptrcopy;
+ wxVaCopy(argptrcopy, argptr);
+
+#ifndef __WXWINCE__
+ // Set errno to 0 to make it determinate if wxVsnprintf fails to set it.
+ errno = 0;
+#endif
+ int len = wxVsnprintf(buf, size, format, argptrcopy);
+ va_end(argptrcopy);
+
+ // some implementations of vsnprintf() don't NUL terminate
+ // the string if there is not enough space for it so
+ // always do it manually
+ // FIXME: This really seems to be the wrong and would be an off-by-one
+ // bug except the code above allocates an extra character.
+ buf[size] = _T('\0');
+
+ // vsnprintf() may return either -1 (traditional Unix behaviour) or the
+ // total number of characters which would have been written if the
+ // buffer were large enough (newer standards such as Unix98)
+ if ( len < 0 )
+ {
+ // NB: wxVsnprintf() may call either wxCRT_VsnprintfW or
+ // wxCRT_VsnprintfA in UTF-8 build; wxUSE_WXVSNPRINTF
+ // is true if *both* of them use our own implementation,
+ // otherwise we can't be sure
+#if wxUSE_WXVSNPRINTF
+ // we know that our own implementation of wxVsnprintf() returns -1
+ // only for a format error - thus there's something wrong with
+ // the user's format string
+ buf[0] = '\0';
+ return -1;
+#else // possibly using system version
+ // assume it only returns error if there is not enough space, but
+ // as we don't know how much we need, double the current size of
+ // the buffer
+#ifndef __WXWINCE__
+ if( (errno == EILSEQ) || (errno == EINVAL) )
+ // If errno was set to one of the two well-known hard errors
+ // then fail immediately to avoid an infinite loop.
+ return -1;
+ else
+#endif // __WXWINCE__
+ // still not enough, as we don't know how much we need, double the
+ // current size of the buffer
+ size *= 2;
+#endif // wxUSE_WXVSNPRINTF/!wxUSE_WXVSNPRINTF
+ }
+ else if ( len >= size )
+ {
+#if wxUSE_WXVSNPRINTF
+ // we know that our own implementation of wxVsnprintf() returns
+ // size+1 when there's not enough space but that's not the size
+ // of the required buffer!
+ size *= 2; // so we just double the current size of the buffer
+#else
+ // some vsnprintf() implementations NUL-terminate the buffer and
+ // some don't in len == size case, to be safe always add 1
+ // FIXME: I don't quite understand this comment. The vsnprintf
+ // function is specifically defined to return the number of
+ // characters printed not including the null terminator.
+ // So OF COURSE you need to add 1 to get the right buffer size.
+ // The following line is definitely correct, no question.
+ size = len + 1;
+#endif
+ }
+ else // ok, there was enough space
+ {
+ break;
+ }
+ }
+
+ // we could have overshot
+ str.Shrink();
projects / wxWidgets.git / blobdiff