1 files changed, 26 insertions, 3 deletions

diff --git a/ot_scan.c b/ot_scan.c
index a96f82b..c4b951a 100644
--- a/ot_scan.c
+++ b/ot_scan.c
@@ -11,7 +11,7 @@
 /* Opentracker */
 #include "ot_scan.h"
 
-size_t scan_udec(const char *src, uint64_t *dest, uint64_t max) {
+size_t scan_uint(const char *src, uint64_t *dest, uint64_t max) {
   unsigned long long value;
   char              *end;
 
@@ -28,9 +28,9 @@ size_t scan_udec(const char *src, uint64_t *dest, uint64_t max) {
   return (size_t)(end - src);
 }
 
-size_t scan_udec_bencode(const char *src, uint64_t *dest, uint64_t max) {
+size_t scan_uint_bencode(const char *src, uint64_t *dest, uint64_t max) {
   uint64_t value;
-  size_t   consumed = scan_udec(src, &value, max);
+  size_t   consumed = scan_uint(src, &value, max);
 
   /* bencode writes no leading zeros, so anything longer than a single digit
      must not begin with one. */
@@ -42,3 +42,26 @@ size_t scan_udec_bencode(const char *src, uint64_t *dest, uint64_t max) {
 
   return consumed;
 }
+
+int scan_int(const char *src, size_t len, int64_t *dest) {
+  int64_t value  = 0;
+  int     negate = 0;
+
+  if (len && *src == '-')
+    --len, ++src, negate = 1;
+  if (!len)
+    return -1;
+
+  while (len--) {
+    if (*src < '0' || *src > '9')
+      return -1;
+    /* A twenty character field of nines does not fit, and silently wrapping
+       would magically heal a nonsense announce */
+    if (value > (INT64_MAX - (*src - '0')) / 10)
+      return -1;
+    value = 10 * value + (*src++ - '0');
+  }
+
+  *dest = negate ? -value : value;
+  return 0;
+}