Function url_base::set_encoded_host_address

Set the host to an address

Synopsis

Declared in header <boost/url/url_base.hpp>

url_base&
set_encoded_host_address(pct_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. This string can contain percent escapes, or can be empty. Escapes in the string are preserved, and 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( "127.0.0.1" ).buffer() == "http://127.0.0.1" );

Postconditions

this->has_authority() == true

Complexity

Linear in this->size() + s.size().

Exception Safety

Strong guarantee. Calls to allocate may throw. Exceptions thrown on invalid input.

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

Exceptions

Name Thrown on

system_error

s contains an invalid percent-encoding.

Parameters

Name Description

s

The string to set.