Set the host to an address

Synopsis

Declared in header </boost/url/url_base.hpp#L1103[boost/url/url_base.hpp,window=blank_]>

url_base&
set_host_address(string_view s);

Description

Depending on the contents of the passed string, this function sets the host:

  • If the string is a valid IPv4 address, then the host is set to the address. The host type is host_type::ipv4.

  • If the string is a valid IPv6 address, then the host is set to that address. The host type is host_type::ipv6.

  • If the string is a valid IPvFuture, then the host is set to that address. The host type is host_type::ipvfuture.

  • Otherwise, the host name is set to the string, which may be empty. Reserved characters in the string are percent-escaped in the result. The host type is host_type::name. In all cases, when this function returns, the URL contains an authority.

Example

assert( url( "http://www.example.com" ).set_host_address( "127.0.0.1" ).buffer() == "http://127.0.0.1" );

Postconditions

this->has_authority() == true

Complexity

Linear in s.size().

Exception Safety

Strong guarantee. Calls to allocate may throw.

BNF

IPv4address = dec-octet "." dec-octet "." dec-octet "." dec-octet

dec-octet   = DIGIT                 ; 0-9
            / %x31-39 DIGIT         ; 10-99
            / "1" 2DIGIT            ; 100-199
            / "2" %x30-34 DIGIT     ; 200-249
            / "25" %x30-35          ; 250-255

IPv6address =                            6( h16 ":" ) ls32
            /                       "::" 5( h16 ":" ) ls32
            / [               h16 ] "::" 4( h16 ":" ) ls32
            / [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
            / [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
            / [ *3( h16 ":" ) h16 ] "::"    h16 ":"   ls32
            / [ *4( h16 ":" ) h16 ] "::"              ls32
            / [ *5( h16 ":" ) h16 ] "::"              h16
            / [ *6( h16 ":" ) h16 ] "::"

ls32        = ( h16 ":" h16 ) / IPv4address
            ; least-significant 32 bits of address

h16         = 1*4HEXDIG
            ; 16 bits of address represented in hexadecimal

IPvFuture     = "v" 1*HEXDIG "." 1*( unreserved / sub-delims / ":" )

reg-name    = *( unreserved / pct-encoded / "-" / ".")

Specification

Return Value

  • ``

Parameters

Name Type

s

string_view