*: eliminate more aliasing warnings

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2010-02-04 18:41:18 +01:00
parent 98a4c7cf3d
commit 12ca080a1c
6 changed files with 40 additions and 36 deletions

View File

@ -201,10 +201,14 @@
* a lvalue. This makes it more likely to not swap them by mistake * a lvalue. This makes it more likely to not swap them by mistake
*/ */
#if defined(i386) || defined(__x86_64__) #if defined(i386) || defined(__x86_64__)
# define move_from_unaligned_int(v, intp) ((v) = *(int*)(intp)) # include <stdint.h>
# define move_from_unaligned16(v, u16p) ((v) = *(uint16_t*)(u16p)) typedef int bb__aliased_int FIX_ALIASING;
# define move_from_unaligned32(v, u32p) ((v) = *(uint32_t*)(u32p)) typedef uint16_t bb__aliased_uint16_t FIX_ALIASING;
# define move_to_unaligned32(u32p, v) (*(uint32_t*)(u32p) = (v)) typedef uint32_t bb__aliased_uint32_t FIX_ALIASING;
# define move_from_unaligned_int(v, intp) ((v) = *(bb__aliased_int*)(intp))
# define move_from_unaligned16(v, u16p) ((v) = *(bb__aliased_uint16_t*)(u16p))
# define move_from_unaligned32(v, u32p) ((v) = *(bb__aliased_uint32_t*)(u32p))
# define move_to_unaligned32(u32p, v) (*(bb__aliased_uint32_t*)(u32p) = (v))
/* #elif ... - add your favorite arch today! */ /* #elif ... - add your favorite arch today! */
#else #else
/* performs reasonably well (gcc usually inlines memcpy here) */ /* performs reasonably well (gcc usually inlines memcpy here) */

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@ -152,24 +152,24 @@ recv_from_to(int fd, void *buf, size_t len, int flags,
if (cmsgptr->cmsg_level == IPPROTO_IP if (cmsgptr->cmsg_level == IPPROTO_IP
&& cmsgptr->cmsg_type == IP_PKTINFO && cmsgptr->cmsg_type == IP_PKTINFO
) { ) {
# define pktinfo(cmsgptr) ( (struct in_pktinfo*)(CMSG_DATA(cmsgptr)) ) const int IPI_ADDR_OFF = offsetof(struct in_pktinfo, ipi_addr);
to->sa_family = AF_INET; to->sa_family = AF_INET;
/*# define pktinfo(cmsgptr) ( (struct in_pktinfo*)(CMSG_DATA(cmsgptr)) )*/
/*to4->sin_addr = pktinfo(cmsgptr)->ipi_addr; - may be unaligned */ /*to4->sin_addr = pktinfo(cmsgptr)->ipi_addr; - may be unaligned */
memcpy(&to4->sin_addr, &pktinfo(cmsgptr)->ipi_addr, sizeof(to4->sin_addr)); memcpy(&to4->sin_addr, (char*)(CMSG_DATA(cmsgptr)) + IPI_ADDR_OFF, sizeof(to4->sin_addr));
/*to4->sin_port = 123; - this data is not supplied by kernel */ /*to4->sin_port = 123; - this data is not supplied by kernel */
# undef pktinfo
break; break;
} }
# if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO) # if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO)
if (cmsgptr->cmsg_level == IPPROTO_IPV6 if (cmsgptr->cmsg_level == IPPROTO_IPV6
&& cmsgptr->cmsg_type == IPV6_PKTINFO && cmsgptr->cmsg_type == IPV6_PKTINFO
) { ) {
# define pktinfo(cmsgptr) ( (struct in6_pktinfo*)(CMSG_DATA(cmsgptr)) ) const int IPI6_ADDR_OFF = offsetof(struct in6_pktinfo, ipi6_addr);
to->sa_family = AF_INET6; to->sa_family = AF_INET6;
/*# define pktinfo(cmsgptr) ( (struct in6_pktinfo*)(CMSG_DATA(cmsgptr)) )*/
/*to6->sin6_addr = pktinfo(cmsgptr)->ipi6_addr; - may be unaligned */ /*to6->sin6_addr = pktinfo(cmsgptr)->ipi6_addr; - may be unaligned */
memcpy(&to6->sin6_addr, &pktinfo(cmsgptr)->ipi6_addr, sizeof(to6->sin6_addr)); memcpy(&to6->sin6_addr, (char*)(CMSG_DATA(cmsgptr)) + IPI6_ADDR_OFF, sizeof(to6->sin6_addr));
/*to6->sin6_port = 123; */ /*to6->sin6_port = 123; */
# undef pktinfo
break; break;
} }
# endif # endif

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@ -75,29 +75,34 @@ int get_prefix(unsigned long netmask);
#endif #endif
int ipcalc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int ipcalc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int ipcalc_main(int argc, char **argv) int ipcalc_main(int argc UNUSED_PARAM, char **argv)
{ {
unsigned opt; unsigned opt;
int have_netmask = 0; bool have_netmask = 0;
in_addr_t netmask, broadcast, network, ipaddr; struct in_addr s_netmask, s_broadcast, s_network, s_ipaddr;
struct in_addr a; /* struct in_addr { in_addr_t s_addr; } and in_addr_t
* (which in turn is just a typedef to uint32_t)
* are essentially the same type. A few macros for less verbosity: */
#define netmask (s_netmask.s_addr)
#define broadcast (s_broadcast.s_addr)
#define network (s_network.s_addr)
#define ipaddr (s_ipaddr.s_addr)
char *ipstr; char *ipstr;
#if ENABLE_FEATURE_IPCALC_LONG_OPTIONS #if ENABLE_FEATURE_IPCALC_LONG_OPTIONS
applet_long_options = ipcalc_longopts; applet_long_options = ipcalc_longopts;
#endif #endif
opt = getopt32(argv, "mbn" IF_FEATURE_IPCALC_FANCY("phs")); opt = getopt32(argv, "mbn" IF_FEATURE_IPCALC_FANCY("phs"));
argc -= optind;
argv += optind; argv += optind;
if (opt & SILENT)
logmode = LOGMODE_NONE; /* suppress error_msg() output */
if (opt & (BROADCAST | NETWORK | NETPREFIX)) { if (opt & (BROADCAST | NETWORK | NETPREFIX)) {
if (argc > 2 || argc <= 0) if (!argv[0] || !argv[1] || argv[2])
bb_show_usage(); bb_show_usage();
} else { } else {
if (argc != 1) if (!argv[0] || argv[1])
bb_show_usage(); bb_show_usage();
} }
if (opt & SILENT)
logmode = LOGMODE_NONE; /* Suppress error_msg() output */
ipstr = argv[0]; ipstr = argv[0];
if (ENABLE_FEATURE_IPCALC_FANCY) { if (ENABLE_FEATURE_IPCALC_FANCY) {
@ -108,8 +113,7 @@ int ipcalc_main(int argc, char **argv)
while (*prefixstr) { while (*prefixstr) {
if (*prefixstr == '/') { if (*prefixstr == '/') {
*prefixstr = (char)0; *prefixstr++ = '\0';
prefixstr++;
if (*prefixstr) { if (*prefixstr) {
unsigned msk; unsigned msk;
netprefix = xatoul_range(prefixstr, 0, 32); netprefix = xatoul_range(prefixstr, 0, 32);
@ -130,42 +134,36 @@ int ipcalc_main(int argc, char **argv)
prefixstr++; prefixstr++;
} }
} }
ipaddr = inet_aton(ipstr, &a);
if (ipaddr == 0) { if (inet_aton(ipstr, &s_ipaddr) == 0) {
bb_error_msg_and_die("bad IP address: %s", argv[0]); bb_error_msg_and_die("bad IP address: %s", argv[0]);
} }
ipaddr = a.s_addr;
if (argc == 2) { if (argv[1]) {
if (ENABLE_FEATURE_IPCALC_FANCY && have_netmask) { if (ENABLE_FEATURE_IPCALC_FANCY && have_netmask) {
bb_error_msg_and_die("use prefix or netmask, not both"); bb_error_msg_and_die("use prefix or netmask, not both");
} }
if (inet_aton(argv[1], &s_netmask) == 0) {
netmask = inet_aton(argv[1], &a);
if (netmask == 0) {
bb_error_msg_and_die("bad netmask: %s", argv[1]); bb_error_msg_and_die("bad netmask: %s", argv[1]);
} }
netmask = a.s_addr;
} else { } else {
/* JHC - If the netmask wasn't provided then calculate it */ /* JHC - If the netmask wasn't provided then calculate it */
if (!ENABLE_FEATURE_IPCALC_FANCY || !have_netmask) if (!ENABLE_FEATURE_IPCALC_FANCY || !have_netmask)
netmask = get_netmask(ipaddr); netmask = get_netmask(ipaddr);
} }
if (opt & NETMASK) { if (opt & NETMASK) {
printf("NETMASK=%s\n", inet_ntoa((*(struct in_addr *) &netmask))); printf("NETMASK=%s\n", inet_ntoa(s_netmask));
} }
if (opt & BROADCAST) { if (opt & BROADCAST) {
broadcast = (ipaddr & netmask) | ~netmask; broadcast = (ipaddr & netmask) | ~netmask;
printf("BROADCAST=%s\n", inet_ntoa((*(struct in_addr *) &broadcast))); printf("BROADCAST=%s\n", inet_ntoa(s_broadcast));
} }
if (opt & NETWORK) { if (opt & NETWORK) {
network = ipaddr & netmask; network = ipaddr & netmask;
printf("NETWORK=%s\n", inet_ntoa((*(struct in_addr *) &network))); printf("NETWORK=%s\n", inet_ntoa(s_network));
} }
if (ENABLE_FEATURE_IPCALC_FANCY) { if (ENABLE_FEATURE_IPCALC_FANCY) {

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@ -87,6 +87,7 @@ int FAST_FUNC arpping(uint32_t test_nip,
/* wait for arp reply, and check it */ /* wait for arp reply, and check it */
timeout_ms = 2000; timeout_ms = 2000;
do { do {
typedef uint32_t aliased_uint32_t FIX_ALIASING;
int r; int r;
unsigned prevTime = monotonic_ms(); unsigned prevTime = monotonic_ms();
@ -107,7 +108,7 @@ int FAST_FUNC arpping(uint32_t test_nip,
&& arp.operation == htons(ARPOP_REPLY) && arp.operation == htons(ARPOP_REPLY)
/* don't check it: Linux doesn't return proper tHaddr (fixed in 2.6.24?) */ /* don't check it: Linux doesn't return proper tHaddr (fixed in 2.6.24?) */
/* && memcmp(arp.tHaddr, from_mac, 6) == 0 */ /* && memcmp(arp.tHaddr, from_mac, 6) == 0 */
&& *((uint32_t *) arp.sInaddr) == test_nip && *(aliased_uint32_t*)arp.sInaddr == test_nip
) { ) {
/* if ARP source MAC matches safe_mac /* if ARP source MAC matches safe_mac
* (which is client's MAC), then it's not a conflict * (which is client's MAC), then it's not a conflict

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@ -65,7 +65,7 @@ struct swap_header_v1 {
uint32_t padding[117]; /* 11..127 */ uint32_t padding[117]; /* 11..127 */
uint32_t badpages[1]; /* 128 */ uint32_t badpages[1]; /* 128 */
/* total 129 32-bit words in 2nd kilobyte */ /* total 129 32-bit words in 2nd kilobyte */
}; } FIX_ALIASING;
#define NWORDS 129 #define NWORDS 129
#define hdr ((struct swap_header_v1*)bb_common_bufsiz1) #define hdr ((struct swap_header_v1*)bb_common_bufsiz1)

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@ -44,6 +44,7 @@ struct mdp_super_block {
int FAST_FUNC volume_id_probe_linux_raid(struct volume_id *id /*,uint64_t off*/, uint64_t size) int FAST_FUNC volume_id_probe_linux_raid(struct volume_id *id /*,uint64_t off*/, uint64_t size)
{ {
typedef uint32_t aliased_uint32_t FIX_ALIASING;
#define off ((uint64_t)0) #define off ((uint64_t)0)
uint64_t sboff; uint64_t sboff;
uint8_t uuid[16]; uint8_t uuid[16];
@ -63,7 +64,7 @@ int FAST_FUNC volume_id_probe_linux_raid(struct volume_id *id /*,uint64_t off*/,
if (mdp->md_magic != cpu_to_le32(MD_MAGIC)) if (mdp->md_magic != cpu_to_le32(MD_MAGIC))
return -1; return -1;
*(uint32_t*)uuid = mdp->set_uuid0; *(aliased_uint32_t*)uuid = mdp->set_uuid0;
memcpy(&uuid[4], &mdp->set_uuid1, 12); memcpy(&uuid[4], &mdp->set_uuid1, 12);
volume_id_set_uuid(id, uuid, UUID_DCE); volume_id_set_uuid(id, uuid, UUID_DCE);