EVB-PIC24 WIZnet, EVB-PIC24 Datasheet - Page 96

• Manufacturer Part Number: EVB-PIC24
• Description: Development Boards & Kits - PIC / DSPIC W3150A+EVAL BOARD BASED ON PIC24
• Manufacturer: WIZnet

Specifications of EVB-PIC24

• Rohs: yes
• Product: Development Kits
• Interface Type: RS-232
• Data Bus Width: 16 bit
• Dimensions: 50 mm x 40 mm

QNAME Field to process the variable length processes and QTYPE, and QCLASS Field are skipped.
dns_answer() analyzes and processes Answer Section. Answer Section is a section where transformation
actually takes effects and it performs appropriate process to TYPE Field of Answer Section.
TYPE of Answer Section has one of values from <Table 3-41 : Constants Definition at QTYPE & QCLASS
Filed> and the value comes from either TYPE_A or TYPE_PTR. In case that the Domain Name is changed
to IP Address, it can get the changed IP Address from TYPE_A and if the IP Address is changed to Domain
Name, Domain Name can be obtained from TYPE_PTR. Changed Domain Name or IP Address are also
processed and extracted by parse_name().
parse_name() processes QNAME Field of Question Section or NAME, RDDATA Field of RRs Section.
qname--
N
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*qname = NULL
RETURN clen
*qname++ = .
nseg == 0
Y
clen++
cp = &dns_buf[(slen & 0x3F) << 8)+*cp]
u_int slen;
int clen =0;
int indirect = 0;
int nseg = 0;
Declare & Initialize Local Variables
<Fig 3.44: parse_name()>
qname_maxlen -= slen +1
Y
Y
slen & 0xC0==0xC0
qname_maxlen < 0
parse_name()
*qname++ = .
slen = *cp++
slen = *cp++
indirect == 0
indirect == 0
indirect == 0
indirect = 1
slen-- != 0
slen== 0
nseg++
N
Y
N
N
N
N
N
Y
Y
N
Y
Y
clen += slen
*qname++ = *cp++
clen++
Not Enough
Memory
RETURN 0
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