GUACAMOLE-1686: Add convenience function for converting integer to st…

…ring.

src/libguac/guacamole/string.h

@@ -29,6 +29,24 @@
 #include <stddef.h>
 #include <string.h>
 
+/**
+ * Convert the provided unsigned integer into a string, returning the number of
+ * characters written into the destination string, or a negative value if an
+ * error occurs.
+ *
+ * @param dest
+ *     The destination string to copy the data into, which should already be
+ *     allocated and at a size that can handle the string representation of the
+ *     inteer.
+ *
+ * @param integer
+ *     The unsigned integer to convert to a string.
+ * 
+ * @return
+ *     The number of characters written into the dest string.
+ */
+int guac_itoa(char* restrict dest, unsigned int integer);
+
 /**
  * Copies a limited number of bytes from the given source string to the given
  * destination buffer. The resulting buffer will always be null-terminated,

src/libguac/string.c

@@ -22,6 +22,7 @@
 #include "guacamole/mem.h"
 
 #include <stddef.h>
+#include <stdio.h>
 #include <string.h>
 
 /**
@@ -44,6 +45,20 @@
  */
 #define REMAINING(n, length) (((n) < (length)) ? 0 : ((n) - (length)))
 
+int guac_itoa(char* restrict dest, unsigned int integer) {
+
+    /* Determine size of string. */
+    int str_size = snprintf(dest, 0, "%i", integer);
+
+    /* If an error occurs, just return that and skip the conversion. */
+    if (str_size < 0)
+        return str_size;
+
+    /* Do the conversion and return. */
+    return snprintf(dest, (str_size + 1), "%i", integer);
+
+}
+
 size_t guac_strlcpy(char* restrict dest, const char* restrict src, size_t n) {
 
 #ifdef HAVE_STRLCPY