diff options
Diffstat (limited to 'src/net')
| -rw-r--r-- | src/net/dhcpopts.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/src/net/dhcpopts.c b/src/net/dhcpopts.c index 4f67f846e..ebd6de757 100644 --- a/src/net/dhcpopts.c +++ b/src/net/dhcpopts.c @@ -24,6 +24,7 @@ #include <assert.h> #include <vsprintf.h> #include <gpxe/list.h> +#include <gpxe/in.h> #include <gpxe/dhcp.h> /** @file @@ -86,6 +87,21 @@ unsigned long dhcp_num_option ( struct dhcp_option *option ) { } /** + * Obtain value of an IPv4-address DHCP option + * + * @v option DHCP option, or NULL + * @v inp IPv4 address to fill in + * + * Parses the IPv4 address value from a DHCP option, if present. It + * is permitted to call dhcp_ipv4_option() with @c option set to NULL; + * in this case the address will be set to 0.0.0.0. + */ +void dhcp_ipv4_option ( struct dhcp_option *option, struct in_addr *inp ) { + if ( option ) + *inp = option->data.in; +} + +/** * Calculate length of a normal DHCP option * * @v option DHCP option @@ -461,6 +477,45 @@ unsigned long find_global_dhcp_num_option ( unsigned int tag ) { } /** + * Find DHCP IPv4-address option, and return its value + * + * @v options DHCP options block + * @v tag DHCP option tag to search for + * @v inp IPv4 address to fill in + * @ret value Numerical value of the option, or 0 if not found + * + * This function exists merely as a notational shorthand for a call to + * find_dhcp_option() followed by a call to dhcp_ipv4_option(). It is + * not possible to distinguish between the cases "option not found" + * and "option has a value of 0.0.0.0" using this function; if this + * matters to you then issue the two constituent calls directly and + * check that find_dhcp_option() returns a non-NULL value. + */ +void find_dhcp_ipv4_option ( struct dhcp_option_block *options, + unsigned int tag, struct in_addr *inp ) { + dhcp_ipv4_option ( find_dhcp_option ( options, tag ), inp ); +} + +/** + * Find DHCP IPv4-address option, and return its value + * + * @v options DHCP options block + * @v tag DHCP option tag to search for + * @v inp IPv4 address to fill in + * @ret value Numerical value of the option, or 0 if not found + * + * This function exists merely as a notational shorthand for a call to + * find_dhcp_option() followed by a call to dhcp_ipv4_option(). It is + * not possible to distinguish between the cases "option not found" + * and "option has a value of 0.0.0.0" using this function; if this + * matters to you then issue the two constituent calls directly and + * check that find_dhcp_option() returns a non-NULL value. + */ +void find_global_dhcp_ipv4_option ( unsigned int tag, struct in_addr *inp ) { + dhcp_ipv4_option ( find_global_dhcp_option ( tag ), inp ); +} + +/** * Delete DHCP option * * @v options DHCP options block |