dhcp: readability cleanups and small code shrink
function old new delta
udhcp_run_script 654 617 -37
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index 24ff82d..c2b21c6 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -229,37 +229,41 @@
/* put all the parameters into the environment */
static char **fill_envp(struct dhcp_packet *packet)
{
- int num_options = 0;
+ int envc;
int i;
char **envp, **curr;
const char *opt_name;
uint8_t *temp;
- uint8_t over = 0;
+ uint8_t overload = 0;
+ /* We need 6 elements for:
+ * "interface=IFACE"
+ * "ip=N.N.N.N" from packet->yiaddr
+ * "siaddr=IP" from packet->siaddr_nip (unless 0)
+ * "boot_file=FILE" from packet->file (unless overloaded)
+ * "sname=SERVER_HOSTNAME" from packet->sname (unless overloaded)
+ * terminating NULL
+ */
+ envc = 6;
+ /* +1 element for each option, +2 for subnet option: */
if (packet) {
for (i = 0; dhcp_optflags[i].code; i++) {
if (udhcp_get_option(packet, dhcp_optflags[i].code)) {
- num_options++;
if (dhcp_optflags[i].code == DHCP_SUBNET)
- num_options++; /* for mton */
+ envc++; /* for mton */
+ envc++;
}
}
- if (packet->siaddr_nip)
- num_options++;
temp = udhcp_get_option(packet, DHCP_OPTION_OVERLOAD);
if (temp)
- over = *temp;
- if (!(over & FILE_FIELD) && packet->file[0])
- num_options++;
- if (!(over & SNAME_FIELD) && packet->sname[0])
- num_options++;
+ overload = *temp;
}
+ curr = envp = xzalloc(sizeof(char *) * envc);
- curr = envp = xzalloc(sizeof(char *) * (num_options + 3));
*curr = xasprintf("interface=%s", client_config.interface);
putenv(*curr++);
- if (packet == NULL)
+ if (!packet)
return envp;
*curr = xmalloc(sizeof("ip=255.255.255.255"));
@@ -274,9 +278,8 @@
goto next;
*curr = xmalloc_optname_optval(temp, &dhcp_optflags[i], opt_name);
putenv(*curr++);
-
- /* Fill in a subnet bits option for things like /24 */
if (dhcp_optflags[i].code == DHCP_SUBNET) {
+ /* Subnet option: make things like "$ip/$mask" possible */
uint32_t subnet;
move_from_unaligned32(subnet, temp);
*curr = xasprintf("mask=%d", mton(subnet));
@@ -291,12 +294,12 @@
sprint_nip(*curr, "siaddr=", (uint8_t *) &packet->siaddr_nip);
putenv(*curr++);
}
- if (!(over & FILE_FIELD) && packet->file[0]) {
+ if (!(overload & FILE_FIELD) && packet->file[0]) {
/* watch out for invalid packets */
*curr = xasprintf("boot_file=%."DHCP_PKT_FILE_LEN_STR"s", packet->file);
putenv(*curr++);
}
- if (!(over & SNAME_FIELD) && packet->sname[0]) {
+ if (!(overload & SNAME_FIELD) && packet->sname[0]) {
/* watch out for invalid packets */
*curr = xasprintf("sname=%."DHCP_PKT_SNAME_LEN_STR"s", packet->sname);
putenv(*curr++);