Attachment 113994 Details for Bug 17289 – [1/6 v2] Use new _dbus_string_get_length_uint() to avoid another -Wsign-compare

[patch] [1/6 v2] Use new _dbus_string_get_length_uint() to avoid another -Wsign-compare

0001-Use-new-_dbus_string_get_length_uint-to-avoid-anothe.patch (text/plain), 2.96 KB, created by Simon McVittie on 2015-03-04 11:58:49 UTC

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Creator: Simon McVittie

Created: 2015-03-04 11:58:49 UTC

Size: 2.96 KB

patch

obsolete

>From df7779b089499409526a76e33b07763cbfdf9bcf Mon Sep 17 00:00:00 2001
>From: Simon McVittie <simon.mcvittie@collabora.co.uk>
>Date: Wed, 4 Mar 2015 11:58:45 +0000
>Subject: [PATCH 1/6] Use new _dbus_string_get_length_uint() to avoid another
> -Wsign-compare
>
>DBusString's length is signed for historical reasons: the right type
>would have been size_t or some other unsigned type. We have a *lot*
>of callers of _dbus_string_get_length(), so it is not really desirable
>to do a flag-day switch; but we know that the length is always in the
>range [0, INT_MAX] that is common to int and unsigned int, so we can
>safely add an unsigned accessor.
>---
> dbus/dbus-string.h       | 16 ++++++++++++++++
> dbus/dbus-sysdeps-unix.c |  8 ++++----
> 2 files changed, 20 insertions(+), 4 deletions(-)
>
>diff --git a/dbus/dbus-string.h b/dbus/dbus-string.h
>index 95a0309..adf709b 100644
>--- a/dbus/dbus-string.h
>+++ b/dbus/dbus-string.h
>@@ -151,6 +151,22 @@ DBUS_PRIVATE_EXPORT
> int           _dbus_string_get_length            (const DBusString  *str);
> #endif /* !_dbus_string_get_length */
> 
>+/**
>+ * Get the string's length as an unsigned integer, for comparison with
>+ * size_t and similar unsigned types that does not trigger compiler
>+ * warnings about potential value changes during conversion.
>+ *
>+ * DBusString lengths are signed for historical reasons, but we know that
>+ * the length is always >= 0 (and DBUS_GENERIC_STRING_PREAMBLE asserts
>+ * that this is the case) so we know that this cast does not change the
>+ * value.
>+ */
>+static inline unsigned int
>+_dbus_string_get_length_uint (const DBusString *str)
>+{
>+  return (unsigned int) _dbus_string_get_length (str);
>+}
>+
> DBUS_PRIVATE_EXPORT
> dbus_bool_t   _dbus_string_lengthen              (DBusString        *str,
>                                                   int                additional_length);
>diff --git a/dbus/dbus-sysdeps-unix.c b/dbus/dbus-sysdeps-unix.c
>index 0bcd5ab..c706952 100644
>--- a/dbus/dbus-sysdeps-unix.c
>+++ b/dbus/dbus-sysdeps-unix.c
>@@ -1689,7 +1689,7 @@ add_linux_security_label_to_credentials (int              client_fd,
>       _dbus_verbose ("getsockopt failed with %s, len now %lu\n",
>                      _dbus_strerror (e), (unsigned long) len);
> 
>-      if (e != ERANGE || len <= _dbus_string_get_length (&buf))
>+      if (e != ERANGE || len <= _dbus_string_get_length_uint (&buf))
>         {
>           _dbus_verbose ("Failed to getsockopt(SO_PEERSEC): %s\n",
>                          _dbus_strerror (e));
>@@ -1714,10 +1714,10 @@ add_linux_security_label_to_credentials (int              client_fd,
>       goto out;
>     }
> 
>-  if (len > _dbus_string_get_length (&buf))
>+  if (len > _dbus_string_get_length_uint (&buf))
>     {
>-      _dbus_verbose ("%lu > %d", (unsigned long) len,
>-                     _dbus_string_get_length (&buf));
>+      _dbus_verbose ("%lu > %u", (unsigned long) len,
>+                     _dbus_string_get_length_uint (&buf));
>       _dbus_assert_not_reached ("getsockopt(SO_PEERSEC) overflowed");
>     }
> 
>-- 
>2.1.4
>

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Attachments on bug 17289: 18494 | 18495 | 113960 | 113966 | 113983 | 113984 | 113988 | 113989 | 113990 | 113991 | 113992 | 113993 | 113994 | 113996 | 114001 | 114002

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