uIP hostname resolver functions
[The uIP TCP/IP stack]

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Detailed Description

The uIP DNS resolver functions are used to lookup a hostname and map it to a numerical IP address. It maintains a list of resolved hostnames that can be queried with the resolv_lookup() function. New hostnames can be resolved using the resolv_query() function.

When a hostname has been resolved (or found to be non-existant), the resolver code calls a callback function called resolv_found() that must be implemented by the module that uses the resolver.

Files
file	resolv.c
	DNS host name to IP address resolver.
file	resolv.h
	DNS resolver code header file.
Functions
void	resolv_found (char *name, u16_t *ipaddr)
	Callback function which is called when a hostname is found.
void	resolv_conf (u16_t *dnsserver)
	Configure which DNS server to use for queries.
u16_t *	resolv_getserver (void)
	Obtain the currently configured DNS server.
void	resolv_init (void)
	Initalize the resolver.
u16_t *	resolv_lookup (char *name)
	Look up a hostname in the array of known hostnames.
void	resolv_query (char *name)
	Queues a name so that a question for the name will be sent out.

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Function Documentation

void resolv_conf (  u16_t *  dnsserver  )

Configure which DNS server to use for queries. Parameters: dnsserver  A pointer to a 4-byte representation of the IP address of the DNS server to be configured.

Here is the call graph for this function:

void resolv_found (  char *  name, u16_t *  ipaddr )

Callback function which is called when a hostname is found. This function must be implemented by the module that uses the DNS resolver. It is called when a hostname is found, or when a hostname was not found. Parameters: name  A pointer to the name that was looked up. ipaddr  A pointer to a 4-byte array containing the IP address of the hostname, or NULL if the hostname could not be found.

u16_t* resolv_getserver (  void   )

Obtain the currently configured DNS server. Returns: A pointer to a 4-byte representation of the IP address of the currently configured DNS server or NULL if no DNS server has been configured.

u16_t* resolv_lookup (  char *  name  )

Look up a hostname in the array of known hostnames. Note: This function only looks in the internal array of known hostnames, it does not send out a query for the hostname if none was found. The function resolv_query() can be used to send a query for a hostname. Returns: A pointer to a 4-byte representation of the hostname's IP address, or NULL if the hostname was not found in the array of hostnames.

void resolv_query (  char *  name  )

Queues a name so that a question for the name will be sent out. Parameters: name  The hostname that is to be queried.

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