dhcp: get rid of last global data

function                                             old     new   delta
udhcpc_main                                         2680    2684      +4
state                                                  1       -      -1
listen_mode                                            1       -      -1
sockfd                                                 4       -      -4
------------------------------------------------------------------------------
(add/remove: 0/3 grow/shrink: 1/0 up/down: 4/-6)               Total: -2 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2019-05-26 13:05:04 +02:00
parent dff2bd733f
commit a4ed2c45b9
3 changed files with 82 additions and 80 deletions

View File

@ -903,13 +903,12 @@ static NOINLINE int d6_recv_raw_packet(struct in6_addr *peer_ipv6, struct d6_pac
/*** Main ***/
static int sockfd = -1;
/* Values for client_config.listen_mode */
#define LISTEN_NONE 0
#define LISTEN_KERNEL 1
#define LISTEN_RAW 2
static smallint listen_mode;
/* Values for client_config.state */
/* initial state: (re)start DHCP negotiation */
#define INIT_SELECTING 0
/* discover was sent, DHCPOFFER reply received */
@ -924,7 +923,6 @@ static smallint listen_mode;
#define RENEW_REQUESTED 5
/* release, possibly manually requested (SIGUSR2) */
#define RELEASED 6
static smallint state;
static int d6_raw_socket(int ifindex)
{
@ -1018,35 +1016,35 @@ static void change_listen_mode(int new_mode)
: "none"
);
listen_mode = new_mode;
if (sockfd >= 0) {
close(sockfd);
sockfd = -1;
client_config.listen_mode = new_mode;
if (client_config.sockfd >= 0) {
close(client_config.sockfd);
client_config.sockfd = -1;
}
if (new_mode == LISTEN_KERNEL)
sockfd = udhcp_listen_socket(/*INADDR_ANY,*/ CLIENT_PORT6, client_config.interface);
client_config.sockfd = udhcp_listen_socket(/*INADDR_ANY,*/ CLIENT_PORT6, client_config.interface);
else if (new_mode != LISTEN_NONE)
sockfd = d6_raw_socket(client_config.ifindex);
/* else LISTEN_NONE: sockfd stays closed */
client_config.sockfd = d6_raw_socket(client_config.ifindex);
/* else LISTEN_NONE: client_config.sockfd stays closed */
}
/* Called only on SIGUSR1 */
static void perform_renew(void)
{
bb_info_msg("performing DHCP renew");
switch (state) {
switch (client_config.state) {
case BOUND:
change_listen_mode(LISTEN_KERNEL);
case RENEWING:
case REBINDING:
state = RENEW_REQUESTED;
client_config.state = RENEW_REQUESTED;
break;
case RENEW_REQUESTED: /* impatient are we? fine, square 1 */
d6_run_script_no_option("deconfig");
case REQUESTING:
case RELEASED:
change_listen_mode(LISTEN_RAW);
state = INIT_SELECTING;
client_config.state = INIT_SELECTING;
break;
case INIT_SELECTING:
break;
@ -1056,10 +1054,10 @@ static void perform_renew(void)
static void perform_d6_release(struct in6_addr *server_ipv6, struct in6_addr *our_cur_ipv6)
{
/* send release packet */
if (state == BOUND
|| state == RENEWING
|| state == REBINDING
|| state == RENEW_REQUESTED
if (client_config.state == BOUND
|| client_config.state == RENEWING
|| client_config.state == REBINDING
|| client_config.state == RENEW_REQUESTED
) {
bb_info_msg("unicasting a release");
send_d6_release(server_ipv6, our_cur_ipv6); /* unicast */
@ -1073,7 +1071,7 @@ static void perform_d6_release(struct in6_addr *server_ipv6, struct in6_addr *ou
*/
d6_run_script_no_option("deconfig");
change_listen_mode(LISTEN_NONE);
state = RELEASED;
client_config.state = RELEASED;
}
///static uint8_t* alloc_dhcp_option(int code, const char *str, int extra)
@ -1174,6 +1172,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
IF_FEATURE_UDHCP_PORT(CLIENT_PORT6 = 546;)
client_config.interface = "eth0";
client_config.script = CONFIG_UDHCPC_DEFAULT_SCRIPT;
client_config.sockfd = -1;
/* Parse command line */
opt = getopt32long(argv, "^"
@ -1278,7 +1277,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
/* Set up the signal pipe */
udhcp_sp_setup();
state = INIT_SELECTING;
client_config.state = INIT_SELECTING;
d6_run_script_no_option("deconfig");
change_listen_mode(LISTEN_RAW);
packet_num = 0;
@ -1297,16 +1296,16 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
/* silence "uninitialized!" warning */
unsigned timestamp_before_wait = timestamp_before_wait;
//bb_error_msg("sockfd:%d, listen_mode:%d", sockfd, listen_mode);
//bb_error_msg("sockfd:%d, listen_mode:%d", client_config.sockfd, client_config.listen_mode);
/* Was opening raw or udp socket here
* if (listen_mode != LISTEN_NONE && sockfd < 0),
* if (client_config.listen_mode != LISTEN_NONE && client_config.sockfd < 0),
* but on fast network renew responses return faster
* than we open sockets. Thus this code is moved
* to change_listen_mode(). Thus we open listen socket
* BEFORE we send renew request (see "case BOUND:"). */
udhcp_sp_fd_set(pfds, sockfd);
udhcp_sp_fd_set(pfds, client_config.sockfd);
tv = timeout - already_waited_sec;
retval = 0;
@ -1348,7 +1347,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
/* We will restart the wait in any case */
already_waited_sec = 0;
switch (state) {
switch (client_config.state) {
case INIT_SELECTING:
if (!discover_retries || packet_num < discover_retries) {
if (packet_num == 0)
@ -1397,11 +1396,11 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
* were seen in the wild. Treat them similarly
* to "no response to discover" case */
change_listen_mode(LISTEN_RAW);
state = INIT_SELECTING;
client_config.state = INIT_SELECTING;
goto leasefail;
case BOUND:
/* 1/2 lease passed, enter renewing state */
state = RENEWING;
client_config.state = RENEWING;
client_config.first_secs = 0; /* make secs field count from 0 */
change_listen_mode(LISTEN_KERNEL);
log1("entering renew state");
@ -1425,7 +1424,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
}
/* Timed out, enter rebinding state */
log1("entering rebinding state");
state = REBINDING;
client_config.state = REBINDING;
/* fall right through */
case REBINDING:
/* Switch to bcast receive */
@ -1441,7 +1440,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
/* Timed out, enter init state */
bb_info_msg("lease lost, entering init state");
d6_run_script_no_option("deconfig");
state = INIT_SELECTING;
client_config.state = INIT_SELECTING;
client_config.first_secs = 0; /* make secs field count from 0 */
/*timeout = 0; - already is */
packet_num = 0;
@ -1461,7 +1460,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
client_config.first_secs = 0; /* make secs field count from 0 */
already_waited_sec = 0;
perform_renew();
if (state == RENEW_REQUESTED) {
if (client_config.state == RENEW_REQUESTED) {
/* We might be either on the same network
* (in which case renew might work),
* or we might be on a completely different one
@ -1496,15 +1495,15 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
int len;
/* A packet is ready, read it */
if (listen_mode == LISTEN_KERNEL)
len = d6_recv_kernel_packet(&srv6_buf, &packet, sockfd);
if (client_config.listen_mode == LISTEN_KERNEL)
len = d6_recv_kernel_packet(&srv6_buf, &packet, client_config.sockfd);
else
len = d6_recv_raw_packet(&srv6_buf, &packet, sockfd);
len = d6_recv_raw_packet(&srv6_buf, &packet, client_config.sockfd);
if (len == -1) {
/* Error is severe, reopen socket */
bb_error_msg("read error: "STRERROR_FMT", reopening socket" STRERROR_ERRNO);
sleep(discover_timeout); /* 3 seconds by default */
change_listen_mode(listen_mode); /* just close and reopen */
change_listen_mode(client_config.listen_mode); /* just close and reopen */
}
/* If this packet will turn out to be unrelated/bogus,
* we will go back and wait for next one.
@ -1521,7 +1520,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
continue;
}
switch (state) {
switch (client_config.state) {
case INIT_SELECTING:
if (packet.d6_msg_type == D6_MSG_ADVERTISE)
goto type_is_ok;
@ -1547,11 +1546,11 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
bb_info_msg("received DHCP NAK (%u)", option->data[4]);
d6_run_script(packet.d6_options,
packet_end, "nak");
if (state != REQUESTING)
if (client_config.state != REQUESTING)
d6_run_script_no_option("deconfig");
change_listen_mode(LISTEN_RAW);
sleep(3); /* avoid excessive network traffic */
state = INIT_SELECTING;
client_config.state = INIT_SELECTING;
client_config.first_secs = 0; /* make secs field count from 0 */
requested_ipv6 = NULL;
timeout = 0;
@ -1572,7 +1571,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
client6_data.server_id = option;
if (packet.d6_msg_type == D6_MSG_ADVERTISE) {
/* enter requesting state */
state = REQUESTING;
client_config.state = REQUESTING;
timeout = 0;
packet_num = 0;
already_waited_sec = 0;
@ -1747,9 +1746,9 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
timeout = 61;
/* enter bound state */
d6_run_script(packet.d6_options, packet_end,
(state == REQUESTING ? "bound" : "renew"));
(client_config.state == REQUESTING ? "bound" : "renew"));
state = BOUND;
client_config.state = BOUND;
change_listen_mode(LISTEN_NONE);
if (opt & OPT_q) { /* quit after lease */
goto ret0;

View File

@ -984,13 +984,12 @@ static NOINLINE int udhcp_recv_raw_packet(struct dhcp_packet *dhcp_pkt, int fd)
/*** Main ***/
static int sockfd = -1;
/* Values for client_config.listen_mode */
#define LISTEN_NONE 0
#define LISTEN_KERNEL 1
#define LISTEN_RAW 2
static smallint listen_mode;
/* Values for client_config.state */
/* initial state: (re)start DHCP negotiation */
#define INIT_SELECTING 0
/* discover was sent, DHCPOFFER reply received */
@ -1005,7 +1004,6 @@ static smallint listen_mode;
#define RENEW_REQUESTED 5
/* release, possibly manually requested (SIGUSR2) */
#define RELEASED 6
static smallint state;
static int udhcp_raw_socket(int ifindex)
{
@ -1102,35 +1100,35 @@ static void change_listen_mode(int new_mode)
: "none"
);
listen_mode = new_mode;
if (sockfd >= 0) {
close(sockfd);
sockfd = -1;
client_config.listen_mode = new_mode;
if (client_config.sockfd >= 0) {
close(client_config.sockfd);
client_config.sockfd = -1;
}
if (new_mode == LISTEN_KERNEL)
sockfd = udhcp_listen_socket(/*INADDR_ANY,*/ CLIENT_PORT, client_config.interface);
client_config.sockfd = udhcp_listen_socket(/*INADDR_ANY,*/ CLIENT_PORT, client_config.interface);
else if (new_mode != LISTEN_NONE)
sockfd = udhcp_raw_socket(client_config.ifindex);
/* else LISTEN_NONE: sockfd stays closed */
client_config.sockfd = udhcp_raw_socket(client_config.ifindex);
/* else LISTEN_NONE: client_config.sockfd stays closed */
}
/* Called only on SIGUSR1 */
static void perform_renew(void)
{
bb_info_msg("performing DHCP renew");
switch (state) {
switch (client_config.state) {
case BOUND:
change_listen_mode(LISTEN_KERNEL);
case RENEWING:
case REBINDING:
state = RENEW_REQUESTED;
client_config.state = RENEW_REQUESTED;
break;
case RENEW_REQUESTED: /* impatient are we? fine, square 1 */
udhcp_run_script(NULL, "deconfig");
case REQUESTING:
case RELEASED:
change_listen_mode(LISTEN_RAW);
state = INIT_SELECTING;
client_config.state = INIT_SELECTING;
break;
case INIT_SELECTING:
break;
@ -1143,10 +1141,10 @@ static void perform_release(uint32_t server_addr, uint32_t requested_ip)
struct in_addr temp_addr;
/* send release packet */
if (state == BOUND
|| state == RENEWING
|| state == REBINDING
|| state == RENEW_REQUESTED
if (client_config.state == BOUND
|| client_config.state == RENEWING
|| client_config.state == REBINDING
|| client_config.state == RENEW_REQUESTED
) {
temp_addr.s_addr = server_addr;
strcpy(buffer, inet_ntoa(temp_addr));
@ -1165,7 +1163,7 @@ static void perform_release(uint32_t server_addr, uint32_t requested_ip)
udhcp_run_script(NULL, "deconfig");
change_listen_mode(LISTEN_NONE);
state = RELEASED;
client_config.state = RELEASED;
}
static uint8_t* alloc_dhcp_option(int code, const char *str, int extra)
@ -1270,6 +1268,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
IF_FEATURE_UDHCP_PORT(CLIENT_PORT = 68;)
client_config.interface = "eth0";
client_config.script = CONFIG_UDHCPC_DEFAULT_SCRIPT;
client_config.sockfd = -1;
str_V = "udhcp "BB_VER;
/* Parse command line */
@ -1397,7 +1396,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
/* We want random_xid to be random... */
srand(monotonic_us());
state = INIT_SELECTING;
client_config.state = INIT_SELECTING;
udhcp_run_script(NULL, "deconfig");
change_listen_mode(LISTEN_RAW);
packet_num = 0;
@ -1415,16 +1414,16 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
/* silence "uninitialized!" warning */
unsigned timestamp_before_wait = timestamp_before_wait;
//bb_error_msg("sockfd:%d, listen_mode:%d", sockfd, listen_mode);
//bb_error_msg("sockfd:%d, listen_mode:%d", client_config.sockfd, client_config.listen_mode);
/* Was opening raw or udp socket here
* if (listen_mode != LISTEN_NONE && sockfd < 0),
* if (client_config.listen_mode != LISTEN_NONE && client_config.sockfd < 0),
* but on fast network renew responses return faster
* than we open sockets. Thus this code is moved
* to change_listen_mode(). Thus we open listen socket
* BEFORE we send renew request (see "case BOUND:"). */
udhcp_sp_fd_set(pfds, sockfd);
udhcp_sp_fd_set(pfds, client_config.sockfd);
tv = timeout - already_waited_sec;
retval = 0;
@ -1466,7 +1465,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
/* We will restart the wait in any case */
already_waited_sec = 0;
switch (state) {
switch (client_config.state) {
case INIT_SELECTING:
if (!discover_retries || packet_num < discover_retries) {
if (packet_num == 0)
@ -1515,11 +1514,11 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
* were seen in the wild. Treat them similarly
* to "no response to discover" case */
change_listen_mode(LISTEN_RAW);
state = INIT_SELECTING;
client_config.state = INIT_SELECTING;
goto leasefail;
case BOUND:
/* 1/2 lease passed, enter renewing state */
state = RENEWING;
client_config.state = RENEWING;
client_config.first_secs = 0; /* make secs field count from 0 */
change_listen_mode(LISTEN_KERNEL);
log1("entering renew state");
@ -1556,7 +1555,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
}
/* Timed out or error, enter rebinding state */
log1("entering rebinding state");
state = REBINDING;
client_config.state = REBINDING;
/* fall right through */
case REBINDING:
/* Switch to bcast receive */
@ -1572,7 +1571,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
/* Timed out, enter init state */
bb_info_msg("lease lost, entering init state");
udhcp_run_script(NULL, "deconfig");
state = INIT_SELECTING;
client_config.state = INIT_SELECTING;
client_config.first_secs = 0; /* make secs field count from 0 */
/*timeout = 0; - already is */
packet_num = 0;
@ -1592,7 +1591,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
client_config.first_secs = 0; /* make secs field count from 0 */
already_waited_sec = 0;
perform_renew();
if (state == RENEW_REQUESTED) {
if (client_config.state == RENEW_REQUESTED) {
/* We might be either on the same network
* (in which case renew might work),
* or we might be on a completely different one
@ -1627,15 +1626,15 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
int len;
/* A packet is ready, read it */
if (listen_mode == LISTEN_KERNEL)
len = udhcp_recv_kernel_packet(&packet, sockfd);
if (client_config.listen_mode == LISTEN_KERNEL)
len = udhcp_recv_kernel_packet(&packet, client_config.sockfd);
else
len = udhcp_recv_raw_packet(&packet, sockfd);
len = udhcp_recv_raw_packet(&packet, client_config.sockfd);
if (len == -1) {
/* Error is severe, reopen socket */
bb_error_msg("read error: "STRERROR_FMT", reopening socket" STRERROR_ERRNO);
sleep(discover_timeout); /* 3 seconds by default */
change_listen_mode(listen_mode); /* just close and reopen */
change_listen_mode(client_config.listen_mode); /* just close and reopen */
}
/* If this packet will turn out to be unrelated/bogus,
* we will go back and wait for next one.
@ -1666,7 +1665,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
continue;
}
switch (state) {
switch (client_config.state) {
case INIT_SELECTING:
/* Must be a DHCPOFFER */
if (*message == DHCPOFFER) {
@ -1708,7 +1707,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
requested_ip = packet.yiaddr;
/* enter requesting state */
state = REQUESTING;
client_config.state = REQUESTING;
timeout = 0;
packet_num = 0;
already_waited_sec = 0;
@ -1763,10 +1762,10 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
"(got ARP reply), declining");
send_decline(/*xid,*/ server_addr, packet.yiaddr);
if (state != REQUESTING)
if (client_config.state != REQUESTING)
udhcp_run_script(NULL, "deconfig");
change_listen_mode(LISTEN_RAW);
state = INIT_SELECTING;
client_config.state = INIT_SELECTING;
client_config.first_secs = 0; /* make secs field count from 0 */
requested_ip = 0;
timeout = tryagain_timeout;
@ -1783,7 +1782,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
requested_ip = packet.yiaddr;
start = monotonic_sec();
udhcp_run_script(&packet, state == REQUESTING ? "bound" : "renew");
udhcp_run_script(&packet, client_config.state == REQUESTING ? "bound" : "renew");
already_waited_sec = (unsigned)monotonic_sec() - start;
timeout = lease_seconds / 2;
if ((unsigned)timeout < already_waited_sec) {
@ -1791,7 +1790,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
timeout = already_waited_sec = 0;
}
state = BOUND;
client_config.state = BOUND;
change_listen_mode(LISTEN_NONE);
if (opt & OPT_q) { /* quit after lease */
goto ret0;
@ -1833,11 +1832,11 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
/* return to init state */
bb_info_msg("received %s", "DHCP NAK");
udhcp_run_script(&packet, "nak");
if (state != REQUESTING)
if (client_config.state != REQUESTING)
udhcp_run_script(NULL, "deconfig");
change_listen_mode(LISTEN_RAW);
sleep(3); /* avoid excessive network traffic */
state = INIT_SELECTING;
client_config.state = INIT_SELECTING;
client_config.first_secs = 0; /* make secs field count from 0 */
requested_ip = 0;
timeout = 0;

View File

@ -24,6 +24,10 @@ struct client_config_t {
uint16_t first_secs;
uint16_t last_secs;
int sockfd;
smallint listen_mode;
smallint state;
} FIX_ALIASING;
/* server_config sits in 1st half of bb_common_bufsiz1 */