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diff --git a/driver_fw/mini-printf.c b/driver_fw/mini-printf.c
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+/*
+ * The Minimal snprintf() implementation
+ *
+ * Copyright (c) 2013,2014 Michal Ludvig <michal@logix.cz>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * * Neither the name of the auhor nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * ----
+ *
+ * This is a minimal snprintf() implementation optimised
+ * for embedded systems with a very limited program memory.
+ * mini_snprintf() doesn't support _all_ the formatting
+ * the glibc does but on the other hand is a lot smaller.
+ * Here are some numbers from my STM32 project (.bin file size):
+ * no snprintf(): 10768 bytes
+ * mini snprintf(): 11420 bytes (+ 652 bytes)
+ * glibc snprintf(): 34860 bytes (+24092 bytes)
+ * Wasting nearly 24kB of memory just for snprintf() on
+ * a chip with 32kB flash is crazy. Use mini_snprintf() instead.
+ *
+ */
+
+#include "mini-printf.h"
+
+static unsigned int
+mini_strlen(const char *s)
+{
+ unsigned int len = 0;
+ while (s[len] != '\0') len++;
+ return len;
+}
+
+static unsigned int
+mini_itoa(int value, unsigned int radix, unsigned int uppercase, unsigned int unsig,
+ char *buffer, unsigned int zero_pad)
+{
+ char *pbuffer = buffer;
+ int negative = 0;
+ unsigned int i, len;
+
+ /* No support for unusual radixes. */
+ if (radix > 16)
+ return 0;
+
+ if (value < 0 && !unsig) {
+ negative = 1;
+ value = -value;
+ }
+
+ /* This builds the string back to front ... */
+ do {
+ int digit = value % radix;
+ *(pbuffer++) = (digit < 10 ? '0' + digit : (uppercase ? 'A' : 'a') + digit - 10);
+ value /= radix;
+ } while (value > 0);
+
+ for (i = (pbuffer - buffer); i < zero_pad; i++)
+ *(pbuffer++) = '0';
+
+ if (negative)
+ *(pbuffer++) = '-';
+
+ *(pbuffer) = '\0';
+
+ /* ... now we reverse it (could do it recursively but will
+ * conserve the stack space) */
+ len = (pbuffer - buffer);
+ for (i = 0; i < len / 2; i++) {
+ char j = buffer[i];
+ buffer[i] = buffer[len-i-1];
+ buffer[len-i-1] = j;
+ }
+
+ return len;
+}
+
+struct mini_buff {
+ char *buffer, *pbuffer;
+ unsigned int buffer_len;
+};
+
+static int
+_putc(int ch, struct mini_buff *b)
+{
+ if ((unsigned int)((b->pbuffer - b->buffer) + 1) >= b->buffer_len)
+ return 0;
+ *(b->pbuffer++) = ch;
+ *(b->pbuffer) = '\0';
+ return 1;
+}
+
+static int
+_puts(char *s, unsigned int len, struct mini_buff *b)
+{
+ unsigned int i;
+
+ if (b->buffer_len - (b->pbuffer - b->buffer) - 1 < len)
+ len = b->buffer_len - (b->pbuffer - b->buffer) - 1;
+
+ /* Copy to buffer */
+ for (i = 0; i < len; i++)
+ *(b->pbuffer++) = s[i];
+ *(b->pbuffer) = '\0';
+
+ return len;
+}
+
+int
+mini_vsnprintf(char *buffer, unsigned int buffer_len, const char *fmt, va_list va)
+{
+ struct mini_buff b;
+ char bf[24];
+ char ch;
+
+ b.buffer = buffer;
+ b.pbuffer = buffer;
+ b.buffer_len = buffer_len;
+
+ while ((ch=*(fmt++))) {
+ if ((unsigned int)((b.pbuffer - b.buffer) + 1) >= b.buffer_len)
+ break;
+ if (ch!='%')
+ _putc(ch, &b);
+ else {
+ char zero_pad = 0;
+ char *ptr;
+ unsigned int len;
+
+ ch=*(fmt++);
+
+ /* Zero padding requested */
+ if (ch=='0') {
+ ch=*(fmt++);
+ if (ch == '\0')
+ goto end;
+ if (ch >= '0' && ch <= '9')
+ zero_pad = ch - '0';
+ ch=*(fmt++);
+ }
+
+ switch (ch) {
+ case 0:
+ goto end;
+
+ case 'u':
+ case 'd':
+ len = mini_itoa(va_arg(va, unsigned int), 10, 0, (ch=='u'), bf, zero_pad);
+ _puts(bf, len, &b);
+ break;
+
+ case 'x':
+ case 'X':
+ len = mini_itoa(va_arg(va, unsigned int), 16, (ch=='X'), 1, bf, zero_pad);
+ _puts(bf, len, &b);
+ break;
+
+ case 'c' :
+ _putc((char)(va_arg(va, int)), &b);
+ break;
+
+ case 's' :
+ ptr = va_arg(va, char*);
+ _puts(ptr, mini_strlen(ptr), &b);
+ break;
+
+ default:
+ _putc(ch, &b);
+ break;
+ }
+ }
+ }
+end:
+ return b.pbuffer - b.buffer;
+}
+
+
+int
+mini_snprintf(char* buffer, unsigned int buffer_len, const char *fmt, ...)
+{
+ int ret;
+ va_list va;
+ va_start(va, fmt);
+ ret = mini_vsnprintf(buffer, buffer_len, fmt, va);
+ va_end(va);
+
+ return ret;
+}