diff --git a/epan/range.c b/epan/range.c
index 7bbf4f8c70..0dce529554 100644
--- a/epan/range.c
+++ b/epan/range.c
@@ -13,6 +13,7 @@
 
 #include "config.h"
 
+#include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
 #include <errno.h>
@@ -22,7 +23,8 @@
 #include <epan/frame_data.h>
 
 #include <epan/range.h>
-#include <stdio.h>
+
+#include <wsutil/strtoi.h>
 
 /*
  * Size of the header of a range_t.
@@ -84,11 +86,11 @@ range_convert_str_work(wmem_allocator_t *scope, range_t **rangep, const gchar *e
    range_t       *range;
    guint         nranges;
    const gchar   *p;
-   char          *endp;
+   const char    *endp;
    gchar         c;
    guint         i;
    guint32       tmp;
-   unsigned long val;
+   guint32       val;
 
    if ( (rangep == NULL) || (es == NULL) )
       return CVT_SYNTAX_ERROR;
@@ -135,8 +137,8 @@ range_convert_str_work(wmem_allocator_t *scope, range_t **rangep, const gchar *e
       } else if (g_ascii_isdigit(c)) {
          /* Subrange starts with the specified number */
          errno = 0;
-         val = strtoul(p, &endp, 0);
-         if (p == endp) {
+         ws_basestrtou32(p, &endp, &val, 0);
+         if (errno == EINVAL) {
             /* That wasn't a valid number. */
             wmem_free(scope, range);
             return CVT_SYNTAX_ERROR;
@@ -181,8 +183,8 @@ range_convert_str_work(wmem_allocator_t *scope, range_t **rangep, const gchar *e
          } else if (g_ascii_isdigit(c)) {
             /* Subrange ends with the specified number. */
             errno = 0;
-            val = strtoul(p, &endp, 0);
-            if (p == endp) {
+            ws_basestrtou32(p, &endp, &val, 0);
+            if (errno == EINVAL) {
                /* That wasn't a valid number. */
                wmem_free(scope, range);
                return CVT_SYNTAX_ERROR;
diff --git a/wsutil/strtoi.c b/wsutil/strtoi.c
index ac97efe163..a70deced89 100644
--- a/wsutil/strtoi.c
+++ b/wsutil/strtoi.c
@@ -102,7 +102,7 @@ DEFINE_WS_STRTOI_BITS(32)
 DEFINE_WS_STRTOI_BITS(16)
 DEFINE_WS_STRTOI_BITS(8)
 
-static gboolean ws_basestrtou64(const gchar* str, const gchar** endptr, guint64* cint, int base)
+gboolean ws_basestrtou64(const gchar* str, const gchar** endptr, guint64* cint, int base)
 {
 	gchar* end;
 	guint64 val;
@@ -160,7 +160,7 @@ gboolean ws_hexstrtou64(const gchar* str, const gchar** endptr, guint64* cint)
 }
 
 #define DEFINE_WS_STRTOU_BITS(bits) \
-static gboolean ws_basestrtou##bits(const gchar* str, const gchar** endptr, guint##bits* cint, int base) \
+gboolean ws_basestrtou##bits(const gchar* str, const gchar** endptr, guint##bits* cint, int base) \
 { \
 	guint64 val; \
 	if (!ws_basestrtou64(str, endptr, &val, base)) { \
diff --git a/wsutil/strtoi.h b/wsutil/strtoi.h
index 1e3fa6acd8..072f05a0c1 100644
--- a/wsutil/strtoi.h
+++ b/wsutil/strtoi.h
@@ -61,6 +61,28 @@ WS_DLL_PUBLIC gboolean ws_hexstrtou32(const gchar* str, const gchar** endptr, gu
 WS_DLL_PUBLIC gboolean ws_hexstrtou16(const gchar* str, const gchar** endptr, guint16* cint);
 WS_DLL_PUBLIC gboolean ws_hexstrtou8 (const gchar* str, const gchar** endptr, guint8*  cint);
 
+/*
+ * \brief Convert a string in the specified base to an unsigned int, with
+ * error checks.
+ * \param str The string to convert
+ * \param endptr A pointer that will store a pointer to the first invalid
+ * character in str, allowing a number to be parsed even if there is trailing
+ * whitespace. If NULL, then the string is assumed to contain only valid
+ * characters (or it will error out).
+ * \param cint The converted integer
+ * \param base The base for the integer; 0 means "if it begins with 0x,
+ * it's hex, otherwise if it begins with 0, it's octal, otherwise it's
+ * decimal".
+ * \return TRUE if the conversion succeeds, FALSE otherwise.
+ * On error, errno is set to EINVAL for unrecognized input and ERANGE
+ * if the resulting number does not fit in the type.
+ */
+
+WS_DLL_PUBLIC gboolean ws_basestrtou64(const gchar* str, const gchar** endptr, guint64* cint, int base);
+WS_DLL_PUBLIC gboolean ws_basestrtou32(const gchar* str, const gchar** endptr, guint32* cint, int base);
+WS_DLL_PUBLIC gboolean ws_basestrtou16(const gchar* str, const gchar** endptr, guint16* cint, int base);
+WS_DLL_PUBLIC gboolean ws_basestrtou8 (const gchar* str, const gchar** endptr, guint8*  cint, int base);
+
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */