diff --git a/TODO b/TODO
index ded7ab96e..6d58cd1b3 100644
--- a/TODO
+++ b/TODO
@@ -34,6 +34,8 @@ Core
- Check incoming packets and log errors!!
+- implement snprintf etc. and clean up debugging and logging functions
+
RIP
~~~
diff --git a/lib/Modules b/lib/Modules
index 18447e1eb..5657ee73c 100644
--- a/lib/Modules
+++ b/lib/Modules
@@ -17,3 +17,5 @@ slab.c
socket.h
unaligned.h
xmalloc.c
+printf.c
+string.h
diff --git a/lib/printf.c b/lib/printf.c
new file mode 100644
index 000000000..dc9ea1b3c
--- /dev/null
+++ b/lib/printf.c
@@ -0,0 +1,291 @@
+/*
+ * BIRD Library -- Formatted Output
+ *
+ * (c) 1991, 1992 Lars Wirzenius & Linus Torvalds
+ *
+ * Hacked up for BIRD by Martin Mares <mj@ucw.cz>
+ */
+
+#include "nest/bird.h"
+#include "string.h"
+
+/* we use this so that we can do without the ctype library */
+#define is_digit(c) ((c) >= '0' && (c) <= '9')
+
+static int skip_atoi(const char **s)
+{
+ int i=0;
+
+ while (is_digit(**s))
+ i = i*10 + *((*s)++) - '0';
+ return i;
+}
+
+#define ZEROPAD 1 /* pad with zero */
+#define SIGN 2 /* unsigned/signed long */
+#define PLUS 4 /* show plus */
+#define SPACE 8 /* space if plus */
+#define LEFT 16 /* left justified */
+#define SPECIAL 32 /* 0x */
+#define LARGE 64 /* use 'ABCDEF' instead of 'abcdef' */
+
+#define do_div(n,base) ({ \
+int __res; \
+__res = ((unsigned long) n) % (unsigned) base; \
+n = ((unsigned long) n) / (unsigned) base; \
+__res; })
+
+static char * number(char * str, long num, int base, int size, int precision
+ ,int type)
+{
+ char c,sign,tmp[66];
+ const char *digits="0123456789abcdefghijklmnopqrstuvwxyz";
+ int i;
+
+ if (type & LARGE)
+ digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+ if (type & LEFT)
+ type &= ~ZEROPAD;
+ if (base < 2 || base > 36)
+ return 0;
+ c = (type & ZEROPAD) ? '0' : ' ';
+ sign = 0;
+ if (type & SIGN) {
+ if (num < 0) {
+ sign = '-';
+ num = -num;
+ size--;
+ } else if (type & PLUS) {
+ sign = '+';
+ size--;
+ } else if (type & SPACE) {
+ sign = ' ';
+ size--;
+ }
+ }
+ if (type & SPECIAL) {
+ if (base == 16)
+ size -= 2;
+ else if (base == 8)
+ size--;
+ }
+ i = 0;
+ if (num == 0)
+ tmp[i++]='0';
+ else while (num != 0)
+ tmp[i++] = digits[do_div(num,base)];
+ if (i > precision)
+ precision = i;
+ size -= precision;
+ if (!(type&(ZEROPAD+LEFT)))
+ while(size-->0)
+ *str++ = ' ';
+ if (sign)
+ *str++ = sign;
+ if (type & SPECIAL) {
+ if (base==8)
+ *str++ = '0';
+ else if (base==16) {
+ *str++ = '0';
+ *str++ = digits[33];
+ }
+ }
+ if (!(type & LEFT))
+ while (size-- > 0)
+ *str++ = c;
+ while (i < precision--)
+ *str++ = '0';
+ while (i-- > 0)
+ *str++ = tmp[i];
+ while (size-- > 0)
+ *str++ = ' ';
+ return str;
+}
+
+int bvsprintf(char *buf, const char *fmt, va_list args)
+{
+ int len;
+ unsigned long num;
+ int i, base;
+ char * str;
+ const char *s;
+
+ int flags; /* flags to number() */
+
+ int field_width; /* width of output field */
+ int precision; /* min. # of digits for integers; max
+ number of chars for from string */
+ int qualifier; /* 'h', 'l', or 'L' for integer fields */
+
+ for (str=buf ; *fmt ; ++fmt) {
+ if (*fmt != '%') {
+ *str++ = *fmt;
+ continue;
+ }
+
+ /* process flags */
+ flags = 0;
+ repeat:
+ ++fmt; /* this also skips first '%' */
+ switch (*fmt) {
+ case '-': flags |= LEFT; goto repeat;
+ case '+': flags |= PLUS; goto repeat;
+ case ' ': flags |= SPACE; goto repeat;
+ case '#': flags |= SPECIAL; goto repeat;
+ case '0': flags |= ZEROPAD; goto repeat;
+ }
+
+ /* get field width */
+ field_width = -1;
+ if (is_digit(*fmt))
+ field_width = skip_atoi(&fmt);
+ else if (*fmt == '*') {
+ ++fmt;
+ /* it's the next argument */
+ field_width = va_arg(args, int);
+ if (field_width < 0) {
+ field_width = -field_width;
+ flags |= LEFT;
+ }
+ }
+
+ /* get the precision */
+ precision = -1;
+ if (*fmt == '.') {
+ ++fmt;
+ if (is_digit(*fmt))
+ precision = skip_atoi(&fmt);
+ else if (*fmt == '*') {
+ ++fmt;
+ /* it's the next argument */
+ precision = va_arg(args, int);
+ }
+ if (precision < 0)
+ precision = 0;
+ }
+
+ /* get the conversion qualifier */
+ qualifier = -1;
+ if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L') {
+ qualifier = *fmt;
+ ++fmt;
+ }
+
+ /* default base */
+ base = 10;
+
+ switch (*fmt) {
+ case 'c':
+ if (!(flags & LEFT))
+ while (--field_width > 0)
+ *str++ = ' ';
+ *str++ = (unsigned char) va_arg(args, int);
+ while (--field_width > 0)
+ *str++ = ' ';
+ continue;
+
+ case 's':
+ s = va_arg(args, char *);
+ if (!s)
+ s = "<NULL>";
+
+ len = strlen(s);
+ if (precision >= 0 && len > precision)
+ len = precision;
+
+ if (!(flags & LEFT))
+ while (len < field_width--)
+ *str++ = ' ';
+ for (i = 0; i < len; ++i)
+ *str++ = *s++;
+ while (len < field_width--)
+ *str++ = ' ';
+ continue;
+
+ case 'p':
+ if (field_width == -1) {
+ field_width = 2*sizeof(void *);
+ flags |= ZEROPAD;
+ }
+ str = number(str,
+ (unsigned long) va_arg(args, void *), 16,
+ field_width, precision, flags);
+ continue;
+
+
+ case 'n':
+ if (qualifier == 'l') {
+ long * ip = va_arg(args, long *);
+ *ip = (str - buf);
+ } else {
+ int * ip = va_arg(args, int *);
+ *ip = (str - buf);
+ }
+ continue;
+
+ /* IP address */
+ case 'I':
+ if (flags & SPECIAL)
+ str = ip_ntox(va_arg(args, ip_addr), str);
+ else {
+ len = ip_ntop(va_arg(args, ip_addr), str) - str;
+ str += len;
+ if (field_width >= 0)
+ while (len++ < STD_ADDRESS_P_LENGTH)
+ *str++ = ' ';
+ }
+ continue;
+
+ /* integer number formats - set up the flags and "break" */
+ case 'o':
+ base = 8;
+ break;
+
+ case 'X':
+ flags |= LARGE;
+ case 'x':
+ base = 16;
+ break;
+
+ case 'd':
+ case 'i':
+ flags |= SIGN;
+ case 'u':
+ break;
+
+ default:
+ if (*fmt != '%')
+ *str++ = '%';
+ if (*fmt)
+ *str++ = *fmt;
+ else
+ --fmt;
+ continue;
+ }
+ if (qualifier == 'l')
+ num = va_arg(args, unsigned long);
+ else if (qualifier == 'h') {
+ if (flags & SIGN)
+ num = va_arg(args, short);
+ else
+ num = va_arg(args, unsigned short);
+ } else if (flags & SIGN)
+ num = va_arg(args, int);
+ else
+ num = va_arg(args, unsigned int);
+ str = number(str, num, base, field_width, precision, flags);
+ }
+ *str = '\0';
+ return str-buf;
+}
+
+int bsprintf(char * buf, const char *fmt, ...)
+{
+ va_list args;
+ int i;
+
+ va_start(args, fmt);
+ i=bvsprintf(buf,fmt,args);
+ va_end(args);
+ return i;
+}
diff --git a/lib/string.h b/lib/string.h
new file mode 100644
index 000000000..9f72cb798
--- /dev/null
+++ b/lib/string.h
@@ -0,0 +1,17 @@
+/*
+ * BIRD Library -- String Functions
+ *
+ * (c) 1998 Martin Mares <mj@ucw.cz>
+ *
+ * Can be freely distributed and used under the terms of the GNU GPL.
+ */
+
+#ifndef _BIRD_STRING_H_
+#define _BIRD_STRING_H_
+
+#include <stdarg.h>
+
+int bsprintf(char *str, const char *fmt, ...);
+int bvsprintf(char *str, const char *fmt, va_list args);
+
+#endif