1 files changed, 21 insertions, 0 deletions
diff --git a/src/libstddjb/uint64_scan_base_max.c b/src/libstddjb/uint64_scan_base_max.c
new file mode 100644
index 0000000..6debe0a
--- /dev/null
+++ b/src/libstddjb/uint64_scan_base_max.c
@@ -0,0 +1,21 @@
+/* ISC license. */
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include <skalibs/uint64.h>
+#include <skalibs/fmtscan.h>
+
+size_t uint64_scan_base_max (char const *s, uint64_t *u, uint8_t base, uint64_t max)
+{
+  uint64_t result = 0 ;
+  size_t pos = 0 ;
+  for (;; pos++)
+  {
+    uint8_t c = fmtscan_num(s[pos], base) ;
+    if (c >= base || result > ((max - c) / base)) break ;
+    result = result * base + c ;
+  }
+  if (pos) *u = result ;
+  return pos ;
+}