From 12ca080a1ca8dfd0aeac54485451b906a7e61b16 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Thu, 4 Feb 2010 18:41:18 +0100 Subject: *: eliminate more aliasing warnings Signed-off-by: Denys Vlasenko --- include/platform.h | 12 +++++++---- libbb/udp_io.c | 12 +++++------ networking/ipcalc.c | 44 +++++++++++++++++++-------------------- networking/udhcp/arpping.c | 3 ++- util-linux/mkswap.c | 2 +- util-linux/volume_id/linux_raid.c | 3 ++- 6 files changed, 40 insertions(+), 36 deletions(-) diff --git a/include/platform.h b/include/platform.h index ab4402e79..dcc61a77b 100644 --- a/include/platform.h +++ b/include/platform.h @@ -201,10 +201,14 @@ * a lvalue. This makes it more likely to not swap them by mistake */ #if defined(i386) || defined(__x86_64__) -# define move_from_unaligned_int(v, intp) ((v) = *(int*)(intp)) -# define move_from_unaligned16(v, u16p) ((v) = *(uint16_t*)(u16p)) -# define move_from_unaligned32(v, u32p) ((v) = *(uint32_t*)(u32p)) -# define move_to_unaligned32(u32p, v) (*(uint32_t*)(u32p) = (v)) +# include +typedef int bb__aliased_int FIX_ALIASING; +typedef uint16_t bb__aliased_uint16_t FIX_ALIASING; +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! */ #else /* performs reasonably well (gcc usually inlines memcpy here) */ diff --git a/libbb/udp_io.c b/libbb/udp_io.c index d9375eac2..24237be99 100644 --- a/libbb/udp_io.c +++ b/libbb/udp_io.c @@ -152,24 +152,24 @@ recv_from_to(int fd, void *buf, size_t len, int flags, if (cmsgptr->cmsg_level == IPPROTO_IP && 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; + /*# define pktinfo(cmsgptr) ( (struct in_pktinfo*)(CMSG_DATA(cmsgptr)) )*/ /*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 */ -# undef pktinfo break; } # if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO) if (cmsgptr->cmsg_level == IPPROTO_IPV6 && 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; + /*# define pktinfo(cmsgptr) ( (struct in6_pktinfo*)(CMSG_DATA(cmsgptr)) )*/ /*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; */ -# undef pktinfo break; } # endif diff --git a/networking/ipcalc.c b/networking/ipcalc.c index 18abc12eb..78558495e 100644 --- a/networking/ipcalc.c +++ b/networking/ipcalc.c @@ -75,29 +75,34 @@ int get_prefix(unsigned long netmask); #endif 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; - int have_netmask = 0; - in_addr_t netmask, broadcast, network, ipaddr; - struct in_addr a; + bool have_netmask = 0; + struct in_addr s_netmask, s_broadcast, s_network, s_ipaddr; + /* 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; #if ENABLE_FEATURE_IPCALC_LONG_OPTIONS applet_long_options = ipcalc_longopts; #endif opt = getopt32(argv, "mbn" IF_FEATURE_IPCALC_FANCY("phs")); - argc -= optind; argv += optind; + if (opt & SILENT) + logmode = LOGMODE_NONE; /* suppress error_msg() output */ if (opt & (BROADCAST | NETWORK | NETPREFIX)) { - if (argc > 2 || argc <= 0) + if (!argv[0] || !argv[1] || argv[2]) bb_show_usage(); } else { - if (argc != 1) + if (!argv[0] || argv[1]) bb_show_usage(); } - if (opt & SILENT) - logmode = LOGMODE_NONE; /* Suppress error_msg() output */ ipstr = argv[0]; if (ENABLE_FEATURE_IPCALC_FANCY) { @@ -108,8 +113,7 @@ int ipcalc_main(int argc, char **argv) while (*prefixstr) { if (*prefixstr == '/') { - *prefixstr = (char)0; - prefixstr++; + *prefixstr++ = '\0'; if (*prefixstr) { unsigned msk; netprefix = xatoul_range(prefixstr, 0, 32); @@ -130,42 +134,36 @@ int ipcalc_main(int argc, char **argv) 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]); } - ipaddr = a.s_addr; - if (argc == 2) { + if (argv[1]) { if (ENABLE_FEATURE_IPCALC_FANCY && have_netmask) { bb_error_msg_and_die("use prefix or netmask, not both"); } - - netmask = inet_aton(argv[1], &a); - if (netmask == 0) { + if (inet_aton(argv[1], &s_netmask) == 0) { bb_error_msg_and_die("bad netmask: %s", argv[1]); } - netmask = a.s_addr; } else { - /* JHC - If the netmask wasn't provided then calculate it */ if (!ENABLE_FEATURE_IPCALC_FANCY || !have_netmask) netmask = get_netmask(ipaddr); } if (opt & NETMASK) { - printf("NETMASK=%s\n", inet_ntoa((*(struct in_addr *) &netmask))); + printf("NETMASK=%s\n", inet_ntoa(s_netmask)); } if (opt & BROADCAST) { 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) { 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) { diff --git a/networking/udhcp/arpping.c b/networking/udhcp/arpping.c index 548796e2b..cf18153f7 100644 --- a/networking/udhcp/arpping.c +++ b/networking/udhcp/arpping.c @@ -87,6 +87,7 @@ int FAST_FUNC arpping(uint32_t test_nip, /* wait for arp reply, and check it */ timeout_ms = 2000; do { + typedef uint32_t aliased_uint32_t FIX_ALIASING; int r; unsigned prevTime = monotonic_ms(); @@ -107,7 +108,7 @@ int FAST_FUNC arpping(uint32_t test_nip, && arp.operation == htons(ARPOP_REPLY) /* don't check it: Linux doesn't return proper tHaddr (fixed in 2.6.24?) */ /* && 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 * (which is client's MAC), then it's not a conflict diff --git a/util-linux/mkswap.c b/util-linux/mkswap.c index 949c71a78..7e32d91ed 100644 --- a/util-linux/mkswap.c +++ b/util-linux/mkswap.c @@ -65,7 +65,7 @@ struct swap_header_v1 { uint32_t padding[117]; /* 11..127 */ uint32_t badpages[1]; /* 128 */ /* total 129 32-bit words in 2nd kilobyte */ -}; +} FIX_ALIASING; #define NWORDS 129 #define hdr ((struct swap_header_v1*)bb_common_bufsiz1) diff --git a/util-linux/volume_id/linux_raid.c b/util-linux/volume_id/linux_raid.c index d1bf0c308..e1c86369d 100644 --- a/util-linux/volume_id/linux_raid.c +++ b/util-linux/volume_id/linux_raid.c @@ -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) { + typedef uint32_t aliased_uint32_t FIX_ALIASING; #define off ((uint64_t)0) uint64_t sboff; 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)) return -1; - *(uint32_t*)uuid = mdp->set_uuid0; + *(aliased_uint32_t*)uuid = mdp->set_uuid0; memcpy(&uuid[4], &mdp->set_uuid1, 12); volume_id_set_uuid(id, uuid, UUID_DCE); -- cgit v1.2.3