libbb/bb_strtonum: always set end ptr, even on error return

function                                             old     new   delta
handle_errors                                         69      61      -8

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 40 insertions, 19 deletions

diff --git a/libbb/bb_strtonum.c b/libbb/bb_strtonum.c
index c66c774f4..949f26bee 100644
--- a/libbb/bb_strtonum.c
+++ b/libbb/bb_strtonum.c
@@ -36,14 +36,14 @@ static unsigned long long ret_ERANGE(void)
         return ULLONG_MAX;
 }
 
-static unsigned long long handle_errors(unsigned long long v, char **endp, char *endptr)
+static unsigned long long handle_errors(unsigned long long v, char **endp)
 {
-        if (endp) *endp = endptr;
+        char next_ch = **endp;
 
         /* errno is already set to ERANGE by strtoXXX if value overflowed */
-        if (endptr[0]) {
+        if (next_ch) {
                 /* "1234abcg" or out-of-range? */
-                if (isalnum(endptr[0]) || errno)
+                if (isalnum(next_ch) || errno)
                         return ret_ERANGE();
                 /* good number, just suspicious terminator */
                 errno = EINVAL;
@@ -57,30 +57,37 @@ unsigned long long FAST_FUNC bb_strtoull(const char *arg, char **endp, int base)
         unsigned long long v;
         char *endptr;
 
+        if (!endp) endp = &endptr;
+        *endp = (char*) arg;
+
         /* strtoul("  -4200000000") returns 94967296, errno 0 (!) */
         /* I don't think that this is right. Preventing this... */
         if (!isalnum(arg[0])) return ret_ERANGE();
 
         /* not 100% correct for lib func, but convenient for the caller */
         errno = 0;
-        v = strtoull(arg, &endptr, base);
-        return handle_errors(v, endp, endptr);
+        v = strtoull(arg, endp, base);
+        return handle_errors(v, endp);
 }
 
 long long FAST_FUNC bb_strtoll(const char *arg, char **endp, int base)
 {
         unsigned long long v;
         char *endptr;
+        char first;
+
+        if (!endp) endp = &endptr;
+        *endp = (char*) arg;
 
         /* Check for the weird "feature":
          * a "-" string is apparently a valid "number" for strto[u]l[l]!
          * It returns zero and errno is 0! :( */
-        char first = (arg[0] != '-' ? arg[0] : arg[1]);
+        first = (arg[0] != '-' ? arg[0] : arg[1]);
         if (!isalnum(first)) return ret_ERANGE();
 
         errno = 0;
-        v = strtoll(arg, &endptr, base);
-        return handle_errors(v, endp, endptr);
+        v = strtoll(arg, endp, base);
+        return handle_errors(v, endp);
 }
 
 #if ULONG_MAX != ULLONG_MAX
@@ -89,23 +96,30 @@ unsigned long FAST_FUNC bb_strtoul(const char *arg, char **endp, int base)
         unsigned long v;
         char *endptr;
 
+        if (!endp) endp = &endptr;
+        *endp = (char*) arg;
+
         if (!isalnum(arg[0])) return ret_ERANGE();
         errno = 0;
-        v = strtoul(arg, &endptr, base);
-        return handle_errors(v, endp, endptr);
+        v = strtoul(arg, endp, base);
+        return handle_errors(v, endp);
 }
 
 long FAST_FUNC bb_strtol(const char *arg, char **endp, int base)
 {
         long v;
         char *endptr;
+        char first;
 
-        char first = (arg[0] != '-' ? arg[0] : arg[1]);
+        if (!endp) endp = &endptr;
+        *endp = (char*) arg;
+
+        first = (arg[0] != '-' ? arg[0] : arg[1]);
         if (!isalnum(first)) return ret_ERANGE();
 
         errno = 0;
-        v = strtol(arg, &endptr, base);
-        return handle_errors(v, endp, endptr);
+        v = strtol(arg, endp, base);
+        return handle_errors(v, endp);
 }
 #endif
 
@@ -115,25 +129,32 @@ unsigned FAST_FUNC bb_strtou(const char *arg, char **endp, int base)
         unsigned long v;
         char *endptr;
 
+        if (!endp) endp = &endptr;
+        *endp = (char*) arg;
+
         if (!isalnum(arg[0])) return ret_ERANGE();
         errno = 0;
-        v = strtoul(arg, &endptr, base);
+        v = strtoul(arg, endp, base);
         if (v > UINT_MAX) return ret_ERANGE();
-        return handle_errors(v, endp, endptr);
+        return handle_errors(v, endp);
 }
 
 int FAST_FUNC bb_strtoi(const char *arg, char **endp, int base)
 {
         long v;
         char *endptr;
+        char first;
+
+        if (!endp) endp = &endptr;
+        *endp = (char*) arg;
 
-        char first = (arg[0] != '-' ? arg[0] : arg[1]);
+        first = (arg[0] != '-' ? arg[0] : arg[1]);
         if (!isalnum(first)) return ret_ERANGE();
 
         errno = 0;
-        v = strtol(arg, &endptr, base);
+        v = strtol(arg, endp, base);
         if (v > INT_MAX) return ret_ERANGE();
         if (v < INT_MIN) return ret_ERANGE();
-        return handle_errors(v, endp, endptr);
+        return handle_errors(v, endp);
 }
 #endif