From: Eugene Syromyatnikov <evgsyr-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
To: strace-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
Cc: dm-devel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org,
mpatocka-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org
Subject: [PATCH 08/21] dm: Use static constants for offset sizes
Date: Sun, 9 Oct 2016 16:30:06 +0300 [thread overview]
Message-ID: <20161009133006.GA3129@obsidian> (raw)
In-Reply-To: <20161005.192828.566127461630656590.yamato-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
This may improve readability an leads to more compact code.
---
dm.c | 58 +++++++++++++++++++++++++++++++---------------------------
1 file changed, 31 insertions(+), 27 deletions(-)
diff --git a/dm.c b/dm.c
index 66b615d..adfa97e 100644
--- a/dm.c
+++ b/dm.c
@@ -102,12 +102,14 @@ static void
dm_decode_dm_target_spec(struct tcb *tcp, const struct dm_ioctl *ioc,
const char *extra, uint32_t extra_size)
{
+ static const uint32_t target_spec_size =
+ sizeof(struct dm_target_spec);
uint32_t i;
uint32_t offset = ioc->data_start;
for (i = 0; i < ioc->target_count; i++) {
- if (offset + (uint32_t) sizeof(struct dm_target_spec) >= offset &&
- offset + (uint32_t) sizeof(struct dm_target_spec) < extra_size) {
+ if (offset + target_spec_size >= offset &&
+ offset + target_spec_size < extra_size) {
uint32_t new_offset;
const struct dm_target_spec *s =
(const struct dm_target_spec *) (extra + offset);
@@ -121,16 +123,14 @@ dm_decode_dm_target_spec(struct tcb *tcp, const struct dm_ioctl *ioc,
QUOTE_0_TERMINATED);
tprints(", string=");
print_quoted_string((const char *) (s + 1), extra_size -
- (offset +
- sizeof(struct dm_target_spec)),
+ (offset + target_spec_size),
QUOTE_0_TERMINATED);
tprintf("}");
if (entering(tcp))
new_offset = offset + s->next;
else
new_offset = ioc->data_start + s->next;
- if (new_offset <= offset +
- (uint32_t) sizeof(struct dm_target_spec))
+ if (new_offset <= offset + target_spec_size)
goto misplaced;
offset = new_offset;
} else {
@@ -145,13 +145,15 @@ static void
dm_decode_dm_target_deps(const struct dm_ioctl *ioc, const char *extra,
uint32_t extra_size)
{
+ static const uint32_t target_deps_dev_offs =
+ offsetof(struct dm_target_deps, dev);
uint32_t offset = ioc->data_start;
- if (offset + (uint32_t) offsetof(struct dm_target_deps, dev) >= offset &&
- offset + (uint32_t) offsetof(struct dm_target_deps, dev) <= extra_size) {
+ if (offset + target_deps_dev_offs >= offset &&
+ offset + target_deps_dev_offs <= extra_size) {
uint32_t i;
- uint32_t space = (extra_size - (offset +
- offsetof(struct dm_target_deps, dev))) / sizeof(__u64);
+ uint32_t space = (extra_size - offset - target_deps_dev_offs) /
+ sizeof(__u64);
const struct dm_target_deps *s =
(const struct dm_target_deps *) (extra + offset);
@@ -173,11 +175,13 @@ static void
dm_decode_dm_name_list(const struct dm_ioctl *ioc, const char *extra,
uint32_t extra_size)
{
+ static const uint32_t name_list_name_offs =
+ offsetof(struct dm_name_list, name);
uint32_t offset = ioc->data_start;
while (1) {
- if (offset + (uint32_t) offsetof(struct dm_name_list, name) >= offset &&
- offset + (uint32_t) offsetof(struct dm_name_list, name) < extra_size) {
+ if (offset + name_list_name_offs >= offset &&
+ offset + name_list_name_offs < extra_size) {
const struct dm_name_list *s =
(const struct dm_name_list *) (extra + offset);
@@ -186,13 +190,12 @@ dm_decode_dm_name_list(const struct dm_ioctl *ioc, const char *extra,
tprintf(", {dev=makedev(%u, %u), name=", major(s->dev),
minor(s->dev));
print_quoted_string(s->name, extra_size - (offset +
- offsetof(struct dm_name_list,
- name)), QUOTE_0_TERMINATED);
+ name_list_name_offs),
+ QUOTE_0_TERMINATED);
tprints("}");
if (!s->next)
break;
- if (offset + s->next <= offset +
- (uint32_t) offsetof(struct dm_name_list, name))
+ if (offset + s->next <= offset + name_list_name_offs)
goto misplaced;
offset = offset + s->next;
} else {
@@ -207,26 +210,25 @@ static void
dm_decode_dm_target_versions(const struct dm_ioctl *ioc, const char *extra,
uint32_t extra_size)
{
+ static const uint32_t target_vers_name_offs =
+ offsetof(struct dm_target_versions, name);
uint32_t offset = ioc->data_start;
while (1) {
- if (offset + (uint32_t) offsetof(struct dm_target_versions, name) >=
- offset &&
- offset + (uint32_t) offsetof(struct dm_target_versions, name) <
- extra_size) {
+ if (offset + target_vers_name_offs >= offset &&
+ offset + target_vers_name_offs < extra_size) {
const struct dm_target_versions *s =
(const struct dm_target_versions *)(extra + offset);
tprints(", {name=");
print_quoted_string(s->name, extra_size - (offset +
- offsetof(struct dm_target_versions,
- name)), QUOTE_0_TERMINATED);
+ target_vers_name_offs),
+ QUOTE_0_TERMINATED);
tprintf(", version=%" PRIu32 ".%" PRIu32 ".%" PRIu32 "}",
s->version[0], s->version[1], s->version[2]);
if (!s->next)
break;
- if (offset + s->next <= offset +
- (uint32_t) offsetof(struct dm_target_versions, name))
+ if (offset + s->next <= offset + target_vers_name_offs)
goto misplaced;
offset = offset + s->next;
} else {
@@ -242,17 +244,19 @@ static void
dm_decode_dm_target_msg(const struct dm_ioctl *ioc, const char *extra,
uint32_t extra_size)
{
+ static const uint32_t target_msg_message_offs =
+ offsetof(struct dm_target_msg, message);
uint32_t offset = ioc->data_start;
- if (offset + (uint32_t) offsetof(struct dm_target_msg, message) >= offset &&
- offset + (uint32_t) offsetof(struct dm_target_msg, message) < extra_size) {
+ if (offset + target_msg_message_offs >= offset &&
+ offset + target_msg_message_offs < extra_size) {
const struct dm_target_msg *s =
(const struct dm_target_msg *) (extra + offset);
tprintf(", {sector=%" PRIu64 ", message=",
(uint64_t) s->sector);
print_quoted_string(s->message, extra_size -
- offsetof(struct dm_target_msg, message),
+ target_msg_message_offs,
QUOTE_0_TERMINATED);
tprints("}");
} else {
--
1.7.10.4
------------------------------------------------------------------------------
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next prev parent reply other threads:[~2016-10-09 13:30 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <alpine.LRH.2.02.1608221155410.17400@file01.intranet.prod.int.rdu2.redhat.com>
[not found] ` <20160822170920.GA5147@altlinux.org>
[not found] ` <alpine.LRH.2.02.1608231303510.7049@file01.intranet.prod.int.rdu2.redhat.com>
[not found] ` <20160824.233543.198328104871315294.yamato@redhat.com>
[not found] ` <20160824.233543.198328104871315294.yamato-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2016-08-25 12:27 ` [PATCH] Re: your dm patch for strace Mikulas Patocka
[not found] ` <alpine.LRH.2.02.1608250823130.24332-Hpncn10jQN4oNljnaZt3ZvA+iT7yCHsGwRM8/txMwJMAicBL8TP8PQ@public.gmane.org>
2016-09-12 17:10 ` Dmitry V. Levin
[not found] ` <20160912171029.GA5263-u2l5PoMzF/Vg9hUCZPvPmw@public.gmane.org>
2016-10-02 21:59 ` Mikulas Patocka
[not found] ` <alpine.LRH.2.02.1610021751280.29417-Hpncn10jQN4oNljnaZt3ZvA+iT7yCHsGwRM8/txMwJMAicBL8TP8PQ@public.gmane.org>
2016-10-05 10:28 ` Masatake YAMATO
[not found] ` <20161005.192828.566127461630656590.yamato-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2016-10-09 13:27 ` [PATCH 00/21] Some possible additions to the DM ioctl " Eugene Syromyatnikov
2016-10-09 13:28 ` [PATCH 01/21] tests/ioctl_dm: Formatting Eugene Syromyatnikov
2016-10-09 13:28 ` [PATCH 02/21] dm: whitespace fixes Eugene Syromyatnikov
2016-10-09 13:28 ` [PATCH 03/21] tests: Working around bounds check Eugene Syromyatnikov
2016-10-09 13:28 ` [PATCH 04/21] dm: Minor output tweaks Eugene Syromyatnikov
2016-10-09 13:29 ` [PATCH 05/21] xlat: Add values for dm_flags Eugene Syromyatnikov
2016-10-09 13:29 ` [PATCH 06/21] dm: Some future-proofing by means of compile-time DM_VERSION_MAJOR check Eugene Syromyatnikov
2016-10-09 13:29 ` [PATCH 07/21] dm: Add definitions for ioctl commands not implemented initially Eugene Syromyatnikov
2016-10-09 13:30 ` Eugene Syromyatnikov [this message]
2016-10-09 13:30 ` [PATCH 09/21] dm: Remove char * cast Eugene Syromyatnikov
2016-10-09 13:30 ` [PATCH 10/21] dm: use => instead of , for splitting output structure from input Eugene Syromyatnikov
2016-10-09 13:30 ` [PATCH 11/21] dm: Compare entering field values with exiting ones Eugene Syromyatnikov
2016-10-09 13:30 ` [PATCH 12/21] dm: Add inttypes.h, include reorder Eugene Syromyatnikov
2016-10-09 13:30 ` [PATCH 13/21] dm: Move printing of dm_ioctl fields before allocation of extra data Eugene Syromyatnikov
2016-10-09 13:30 ` [PATCH 14/21] dm: replace abbrev branching with goto Eugene Syromyatnikov
2016-10-09 13:31 ` [PATCH 15/21] dm: Additional data_size/data_start checks Eugene Syromyatnikov
2016-10-09 13:31 ` [PATCH 16/21] dm: Add comment regarding intended fall-through in switch statement Eugene Syromyatnikov
2016-10-09 13:31 ` [PATCH 17/21] dm: Add data_size and data_offset fields to output Eugene Syromyatnikov
2016-10-09 13:31 ` [PATCH 18/21] tests/ioctl_dm: Allow passing size and data_start to init_s Eugene Syromyatnikov
2016-10-09 13:31 ` [PATCH 19/21] dm: Add check whether command uses parameters Eugene Syromyatnikov
2016-10-09 13:31 ` [PATCH 20/21] dm: Fix printing of version field Eugene Syromyatnikov
2016-10-09 13:31 ` [PATCH 21/21] dm: rewrite structure decoding Eugene Syromyatnikov
2016-10-10 10:27 ` [PATCH] Re: your dm patch for strace Mikulas Patocka
2016-10-11 22:38 ` [PATCH 0/9] Additional checks for strace DM ioctl decoder test Eugene Syromyatnikov
2016-10-19 20:31 ` [PATCH] device mapper ioctl Mikulas Patocka
[not found] ` <alpine.LRH.2.02.1610191626360.628-Hpncn10jQN4oNljnaZt3ZvA+iT7yCHsGwRM8/txMwJMAicBL8TP8PQ@public.gmane.org>
2016-11-10 21:01 ` Eugene Syromyatnikov
[not found] ` <CACGkJdts9AKHnXb+b6J2kfpDNZJZW12WaNaYukrA11PHtAydag-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2016-11-11 3:13 ` Masatake YAMATO
2016-10-11 22:38 ` [PATCH 1/9] util: Add support for QUOTE_0_TERMINATED in user_style to ptrintstr_ex Eugene Syromyatnikov
2016-10-11 22:38 ` [PATCH 2/9] tests: Add check for printing of overlength strings to ioctl_dm test Eugene Syromyatnikov
2016-10-11 22:38 ` [PATCH 3/9] tests: Add check for presence of HAVE_LINUX_DM_IOCTL_H macro definition " Eugene Syromyatnikov
2016-10-11 22:38 ` [PATCH 4/9] tests/ioctl_dm: whitespace Eugene Syromyatnikov
2016-10-11 22:38 ` [PATCH 5/9] dm: Fix comma printing for the case when dm_target_msg structure is inaccessible Eugene Syromyatnikov
2016-10-11 22:39 ` [PATCH 6/9] tests/ioctl_dm: overly long string printing checks Eugene Syromyatnikov
2016-10-11 22:39 ` [PATCH 7/9] tests: Some additional checks for ioctl_dm test Eugene Syromyatnikov
2016-10-11 22:39 ` [PATCH 8/9] tests: Add ioctl_dm to .gitignore Eugene Syromyatnikov
2016-10-11 22:39 ` [PATCH 9/9] tests: Add checks for abbreviated DM ioctl output Eugene Syromyatnikov
2016-10-08 17:45 ` [PATCH] Re: your dm patch for strace Eugene Syromyatnikov
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