1 files changed, 51 insertions, 0 deletions
diff --git a/src/utils.c b/src/utils.c
index d63edcc..4c6224d 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -2,6 +2,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <ctype.h>
 #include <stdarg.h>
 #include <fcntl.h>
 #include <signal.h>
@@ -25,6 +26,7 @@ char *arg0 = NULL;
 static int null_fd = -1;
 
 static void sighandler_child(int signo);
+static inline void bin2hex_char(unsigned char c, char hexc[5]);
 
 
 int set_fd_nonblock(int fd)
@@ -445,3 +447,52 @@ int update_setgroups_self(int allow)
     return 0;
 }
 #endif
+
+static inline void bin2hex_char(unsigned char c, char hexc[5])
+{
+    static const char hexalnum[] = "0123456789ABCDEF";
+
+    hexc[0] = '\\';
+    hexc[1] = 'x';
+    hexc[2] = hexalnum[ (c >> 4)%16 ];
+    hexc[3] = hexalnum[ (c & 0x0F)%16 ];
+    hexc[4] = 0;
+}
+
+void escape_ascii_string(const char ascii[], size_t siz, char **dest, size_t *newsiz)
+{
+    char hexbyte[5];
+    const size_t binsiz = 4;
+    size_t i, j, ns;
+
+    assert(ascii && dest && newsiz);
+
+    ns = 0;
+    for (i = 0; i < siz; ++i) {
+        if (isprint(ascii[i]))
+            ns++;
+        else
+            ns += binsiz;
+    }
+
+    if (ns > *newsiz) {
+        if (*dest)
+            free(*dest);
+        *dest = (char *) malloc(sizeof(char) * (ns+1));
+        assert(*dest);
+        (*newsiz) = ns;
+    }
+
+    for (i = 0, j = 0; i < siz && j < ns; ++i) {
+        if (isprint(ascii[i])) {
+            (*dest)[j] = ascii[i];
+            j++;
+        } else {
+            bin2hex_char(ascii[i], hexbyte);
+            snprintf((*dest)+j, binsiz+1, "%s", hexbyte);
+            j += binsiz;
+        }
+    }
+
+    (*dest)[ns] = 0;
+}