Windows patch: _dbus_printf_length

[Peter Kümmel]

Here a next windows patch:

changelog entry:

	* dbus/dbus-sysdeps.h: add _dbus_printf_length
	* dbus/dbus-sysdeps.c: add _dbus_printf_length


Peter
-------------- next part --------------
Index: dbus/dbus-string.c
===================================================================
--- dbus/dbus-string.c  (revision 49)
+++ dbus/dbus-string.c  (working copy)
@@ -1193,7 +1193,6 @@
                                     va_list            args)
 {
   int len;
-  char c;
   va_list args_copy;

   DBUS_STRING_PREAMBLE (str);
@@ -1201,7 +1200,7 @@
   DBUS_VA_COPY (args_copy, args);

   /* Measure the message length without terminating nul */
-  len = vsnprintf (&c, 1, format, args);
+  len = _dbus_printf_length (format, args);

   if (!_dbus_string_lengthen (str, len))
     {
     
     
Index: dbus/dbus-sysdeps.h
===================================================================
--- dbus/dbus-sysdeps.h (revision 49)
+++ dbus/dbus-sysdeps.h (working copy)
@@ -272,6 +272,10 @@

 void _dbus_exit (int code) _DBUS_GNUC_NORETURN;

+int _dbus_printf_length (const char *format,
+                         va_list args);
+
+
 /**
  * Portable struct with stat() results
  */
-------------- next part --------------
relating notes:

> +#ifdef DBUS_WIN
> +#include <malloc.h>
> +#endif

(Havoc) What function in here requires malloc.h? Can we abstract it?

>  /**
>   * @defgroup DBusString string class
>   * @ingroup  DBusInternals
> @@ -1193,7 +1197,6 @@
>                                      va_list            args)
>  {
>    int len;
> -  char c;
>    va_list args_copy;
>  
>    DBUS_STRING_PREAMBLE (str);
> @@ -1201,7 +1204,34 @@
>    DBUS_VA_COPY (args_copy, args);
>  
>    /* Measure the message length without terminating nul */
> +#ifndef DBUS_WIN
> +  {
> +    char c;
>    len = vsnprintf (&c, 1, format, args);
> +  }
> +#else
> +  /* MSVCRT's vsnprintf semantics are a bit different */
> +  /* The C library source in the Platform SDK indicates that this
> +   * would work, but alas, it doesn't. At least not on Windows
> +   * 2000. Presumably those sources correspond to the C library on
> +   * some newer or even future Windows version.
> +   *
> +    len = _vsnprintf (NULL, _DBUS_INT_MAX, format, args);
> +   */
> +  {
> +    char p[1024];
> +    len = vsnprintf (p, sizeof(p)-1, format, args);
> +    if (len == -1) // try again
> +      {
> +        char *p;
> +        p = malloc (strlen(format)*3);
> +        len = vsnprintf (p, sizeof(p)-1, format, args);
> +        free(p);

(Havoc) If the malloc.h include was for this, just use _dbus_malloc instead here. 
(Havoc) Also, I think it would be better to add a _dbus_printf_length() 
(Havoc) or something to dbus-sysdeps




changelog entry: 

	* dbus/dbus-sysdeps.h: add _dbus_printf_length
	* dbus/dbus-sysdeps.c: add _dbus_printf_length