[lcd4linux @ 2004-02-27 07:06:24 by reinelt]

new function 'qprintf()' (simple but quick snprintf() replacement)

git-svn-id: https://ssl.bulix.org/svn/lcd4linux/trunk@379 3ae390bd-cb1e-0410-b409-cd5a39f66f1f

qprintf.c

@@ -0,0 +1,143 @@
+/* $Id: qprintf.c,v 1.1 2004/02/27 07:06:26 reinelt Exp $
+ *
+ * simple but quick snprintf() replacement
+ *
+ * Copyright 2004 Michael Reinelt <reinelt@eunet.at>
+ * Copyright 2004 The LCD4Linux Team <lcd4linux-devel@users.sourceforge.net>
+ *
+ * derived from a patch from Martin Hejl which is
+ * Copyright 2003 Martin Hejl (martin@hejl.de)
+ *
+ * This file is part of LCD4Linux.
+ *
+ * LCD4Linux is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * LCD4Linux is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ *
+ * $Log: qprintf.c,v $
+ * Revision 1.1  2004/02/27 07:06:26  reinelt
+ * new function 'qprintf()' (simple but quick snprintf() replacement)
+ *
+ */
+
+/* 
+ * exported functions:
+ * 
+ * int qprintf(char *str, size_t size, const char *format, ...)
+ *   works like snprintf(), but format only knows about %d and %s
+ */
+
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include <string.h>
+
+static char *itoa(char* buffer, size_t size, int value)
+{
+  char *p;
+  int sign;
+ 
+  // sanity checks
+  if (buffer==NULL || size<2) return (NULL);
+  
+  // remember sign of value
+  sign = 0;
+  if (value < 0) {
+    sign  = 1;
+    value = -value;
+  }
+  
+  // p points to last char
+  p = buffer+size-1;
+  
+  // set terminating zero
+  *p='\0';
+  
+  do {
+    *--p = value%10 + '0';
+    value = value/10;
+  } while (value!=0 && p>buffer);
+  
+  if (sign && p>buffer)
+    *--p = '-';
+  
+  return p;
+} 
+
+
+int qprintf(char *str, size_t size, const char *format, ...) {
+
+  va_list ap;
+  const char *src;
+  char *dst;
+  int len;
+  
+  src = format;
+  dst = str;
+  len = 0;
+  
+  // leave room for terminating zero 
+  size--;
+  
+  va_start(ap, format);
+  
+  while (len < size) {
+    
+    if (*src=='%') {
+      char buf[12], *s;
+      int d;
+      switch (*++src) {
+      case 's':
+	src++;
+	s = va_arg(ap, char *);
+	while (len < size && *s != '\0') {
+	  len++;
+	  *dst++ = *s++;
+	}
+	break;
+      case 'd':
+	src++;
+	d = va_arg(ap, int);
+	s = itoa (buf, sizeof(buf), d);
+	while (len < size && *s != '\0') {
+	  len++;
+	  *dst++ = *s++;
+	}
+	break;
+      default:
+	len++;
+	*dst++ = '%';
+      }
+    } else {
+      len++;
+      *dst++ = *src;
+      if (*src++ == '\0') break;
+    }
+  }
+  
+  va_end(ap);
+  
+  // enforce terminating zero
+  if (len>=size && *(dst-1)!='\0') {
+    len++;
+    *dst='\0';
+  }
+  
+  // do not count terminating zero
+  return len-1;
+}
+