[xml] [patch] xmlStrVPrintf

[Aleksey Sanin <aleksey aleksey com>]

Daniel,

I found that in addition to xmlStrPrintf I need xmlStrVPrintf function
for strings formatting. It's a trivial wrapper around Trio function and 
I hope
that you wouldn't object to add this function to LibXML2 API.

Thank you in advance,

Aleksey


Index: parser.c
===================================================================
RCS file: /cvs/gnome/gnome-xml/parser.c,v
retrieving revision 1.340
diff -u -r1.340 parser.c
--- parser.c    28 Oct 2003 23:06:30 -0000      1.340
+++ parser.c    29 Oct 2003 04:03:56 -0000
@@ -2482,6 +2482,30 @@
     return(ret);
 }
 
+/**
+ * xmlStrVPrintf:
+ * @buf:   the result buffer.
+ * @len:   the result buffer length.
+ * @msg:   the message with printf formatting.
+ * @ap:    extra parameters for the message.
+ *
+ * Formats @msg and places result into @buf.
+ *
+ * Returns the number of characters written to @buf or -1 if an error occurs.
+ */
+int 
+xmlStrVPrintf(xmlChar *buf, int len, const xmlChar *msg, va_list ap) {
+    int ret;
+    
+    if((buf == NULL) || (msg == NULL)) {
+       return(-1);
+    }
+    
+    ret = vsnprintf((char *) buf, len, (const char *) msg, ap);
+    buf[len - 1] = 0; /* be safe ! */
+    
+    return(ret);
+}
 /************************************************************************
  *                                                                     *
  *             Commodity functions, cleanup needed ?                   *
Index: include/libxml/parser.h
===================================================================
RCS file: /cvs/gnome/gnome-xml/include/libxml/parser.h,v
retrieving revision 1.107
diff -u -r1.107 parser.h
--- include/libxml/parser.h     28 Oct 2003 21:31:45 -0000      1.107
+++ include/libxml/parser.h     29 Oct 2003 04:03:58 -0000
@@ -9,6 +9,8 @@
 #ifndef __XML_PARSER_H__
 #define __XML_PARSER_H__
 
+#include <stdarg.h>
+
 #include <libxml/xmlversion.h>
 #include <libxml/tree.h>
 #include <libxml/dict.h>
@@ -863,6 +865,12 @@
                                         int len,
                                         const xmlChar *msg,
                                         ...);
+
+XMLPUBFUN int XMLCALL  
+               xmlStrVPrintf           (xmlChar *buf,
+                                        int len,
+                                        const xmlChar *msg,
+                                        va_list ap);
 
 /*
  * Basic parsing Interfaces