Added printf style format method for String.

Added utility method to append and align a string on a specified size.


git-svn-id: http://yate.null.ro/svn/yate/trunk@5959 acf43c95-373e-0410-b603-e72c3f656dc1

engine/String.cpp

@@ -998,6 +998,77 @@ String& String::append(double value, unsigned int decimals)
     return operator+=(buf);
 }
 
+char* string_printf(unsigned int length, const char* format, va_list& va)
+{
+    if (!format)
+	return 0;
+    char* buf = (char*)::malloc(length + 1);
+    if (!buf) {
+	Debug("String",DebugFail,"malloc(%d) returned NULL!",length);
+	return 0;
+    }
+    int len = ::vsnprintf(buf,length,format,va);
+    buf[len] = 0;
+    return buf;
+}
+
+String& String::printf(unsigned int length, const char* format,  ...)
+{
+    va_list va;
+    va_start(va,format);
+    char* buf = string_printf(length,format,va);
+    va_end(va);
+    if (!buf)
+	return *this;
+    char* old = m_string;
+    m_string = buf;
+    ::free(old);
+    changed();
+    return *this;
+}
+
+String& String::printf(const char* format, ...)
+{
+    va_list va;
+    va_start(va,format);
+    char* buf = string_printf(256,format,va);
+    va_end(va);
+    if (!buf)
+	return *this;
+    char* old = m_string;
+    m_string = buf;
+    ::free(old);
+    changed();
+    return *this;
+}
+
+String& String::appendFixed(unsigned int space, const char* str, unsigned int len, char fill, int align)
+{
+    if (len == (unsigned int)-1)
+	len = ::strlen(str);
+    if (!str || len == 0)
+	return *this;
+    int alignPos = 0;
+    if (len < space) {
+	if (align == Center)
+	    alignPos = space / 2 - len / 2;
+	else if (align == Right)
+	    alignPos = space - len;
+    } else
+	len = space;
+    char* buf = (char*)::malloc(space + 1);
+    if (!buf) {
+	Debug("String",DebugFail,"malloc(%d) returned NULL!",space);
+	return *this;
+    }
+    ::memset(buf,fill,space);
+    ::memcpy(buf + alignPos,str,len);
+    buf[space] = 0;
+    operator+=(buf);
+    ::free(buf);
+    return *this;
+}
+
 bool String::operator==(const char* value) const
 {
     if (!m_string)

yateclass.h

@@ -31,6 +31,7 @@
 #include <stddef.h>
 #include <unistd.h>
 #include <errno.h>
+#include <stdarg.h>
 
 #ifndef _WORDSIZE
 #if defined(__arch64__) || defined(__x86_64__) \
@@ -1822,6 +1823,12 @@ private:
 class YATE_API String : public GenObject
 {
 public:
+    enum Align {
+	Left = 0,
+	Center,
+	Right
+    };
+
     /**
      * Creates a new, empty string.
      */
@@ -2445,6 +2452,40 @@ public:
      */
     String& append(double value, unsigned int decimals = 3);
 
+    /**
+     * Add the parameters in a printf style
+     * @param format The output format.
+     * NOTE: The length of the resulting string will be at most 256
+     */
+    String& printf(const char* format, ...) FORMAT_CHECK(2);
+
+    /**
+     * Add the parameters in a printf style
+     * @param length maximum length of the resulting string
+     * @param format The output format.
+     */
+    String& printf(unsigned int length, const char* format,  ...) FORMAT_CHECK(3);
+
+    /**
+     * Append a string and align it.
+     * @param space The space in wich the str will pe aligned.
+     * @param str The string to append
+     * @param len The str length
+     * @param fill Character to fill the empty space.
+     * @param align The alignment mode.
+     */
+    String& appendFixed(unsigned int space, const char* str, unsigned int len = -1, char fill = ' ', int align = Left);
+
+     /**
+      * Append a string and align it.
+      * @param space The space in wich the str will pe aligned.
+      * @param str The string to append
+      * @param fill Character to fill the empty space.
+      * @param align The alignment mode.
+      */
+    inline String& appendFixed(unsigned int space, const String& str, char fill = ' ', int align = Left)
+	{ return appendFixed(space,str.c_str(),str.length(),fill,align); }
+
     /**
      * Locate the first instance of a character in the string
      * @param what Character to search for