FBB::EoiBuf(3bobcat)

📦
version 6.15.01 · 7 versions
, in ubuntu stonking

💖 FBB::EoiBuf 💖

okay bestie, welcome to FBB::EoiBuf from the bobcat manual pages (that's the 3bobcat bit, iykyk) ✨

🌸 NAME 🌸

FBB::EoiBuf — a std::streambuf class offering an eoi manipulator. literally that's the whole vibe 🎀

✨ SYNOPSIS ✨

#include <bobcat/eoibuf>
Linking option: -lbobcat

🦋 DESCRIPTION 🦋

So. The class EoiBuf inherits from Eoi and may therefore be used as a base class of classes specializing std::streambuf. It also provides a configurable character buffer for storing characters received from their devices. 🌈

Here's the tea, bestie: often, when deriving classes from std::streambuf, the derived classes must implement storage to and retrieval from a character buffer. Not me having to write that from scratch every single time 😭. By deriving from EoiBuf, buffer-handling is automatically provided: it contains a (resizable) character buffer, and offers a setp member as well as a setg member that can be used to specify the index range of the buffer from which extractions receive characters. 💅

Also — and this part is iconic — when overriding its base class's eoi_ member it can be used to signal the end of input inserted into std::ostream classes using EoiBuf objects as std::streambuf objects. 👑

💜 NAMESPACE 💜

FBB

All constructors, members, operators and manipulators mentioned in this man-page are defined in the namespace FBB. periodt.

🧚 INHERITS FROM 🧚

FBB::Eoi (and thus from: std::streambuf)

so yeah, you're getting the whole family tree, no cap 🌳

🎀 PROTECTED CONSTRUCTOR 🎀

Analogously to std::streambuf, only protected constructors are available. so you can't just new one up in the middle of the street, babe 🙈

  • EoiBuf() — The default constructor initializes an empty buffer. ✨
  • EoiBuf(size_t size) — This initializes an empty buffer of a predefined size of size characters .

Note that there's no inherent limit to the size of the internal buffer: its size can always be enlarged or reduced. it's giving elastic 💅

🚨 Copy and move constructors (and assignment operators) are not available. not a thing. don't try it.

💅 PROTECTED MEMBER FUNCTIONS 💅

All members of std::streambuf and Eoi are available, as FBB::EoiBuf inherits from these classes. you get it all, bestie, no gatekeeping 🫶

  • std::string &buffer() — A reference to the internal buffer is returned; 🍓
  • size_t bufSize() const — The length (size) of the internal buffer is returned; 📏
  • void resize(size_t size) — The size of the internal buffer is changed to size characters; 🌸
  • void setg(unsigned next, unsigned beyond) — The streambuf::eback member returns the address of the internal buffer's first character, streambuf::gptr returns the address of the internal buffer's next character, streambuf::egptr returns the address of the internal buffer's beyond character; 🔥
  • void setp() — The streambuf::pbase and pptr members return the address of the internal buffer's first character, streambuf::epptr returns the address immediately beyond the internal buffer's last character; ✨
  • unsigned char *ucharPtr() — The address of the first character of the internal buffer is returned as a pointer to an unsigned character; 👑
  • unsigned char const *ucharPtr() const — Same as the previous member, but this time the address of the first character of the internal buffer is returned as a pointer to an immutable unsigned character. 🔒

🌟 PROTECTED STATIC MEMBER FUNCTIONS 🌟

The following two static members are provided as convenient functions for derived classes to convert the address of the first character of std::string objects to pointers to unsigned characters:

  • unsigned char *ucharPtr(std::string &str) — The address of the first character of str is returned as a pointer to an unsigned character; 💖
  • unsigned char const *ucharPtr(std::string const &str) const — Same as the previous member, but this time the address of the first character of str is returned as a pointer to an immutable unsigned character. 🦋

🌈 EXAMPLE 🌈

The following two functions are defined in the (internally used only) class FBB::OSymCryptBase, which is the base class of osymcryptstreambuf(3bobcat). internally used only, so don't come for me about it 💀

  • evpUpdate — updates the ongoing encryption or decryption, e.g., using the openssl function EVP_EncryptUpdate, using ucharPtr to access characters currently in EoiBuf's buffer:
#include "osymcryptbase.ih"

void OSymCryptBase::evpUpdate()
{
    size_t inBufRead = pptr() - pbase();    // # read chars

    checkOutBufSize(inBufRead);

    int nOutputChars;

    if (not ((*d_evpUpdate)(                // en/decrypt the bytes in d_inBuf
            ctx(),
            uOutBuf(), &nOutputChars,
            ucharPtr(), inBufRead
        ))
    )
        throw Exception{} << "EVP_{En,De}cryptUpdate failed";

    d_outStream.write(outBuf(), nOutputChars);      // write the processed
                                                    // chars to d_outSteam

    setp();
}
  • eoi_ — overrides FBB::Eoi::eoi_() function, preventing new information from being inserted into the FBB::OSymCryptBase object (and thus from being inserted into its FBB::OSymCryptStreambuf derived class):
#include "osymcryptbase.ih"

void OSymCryptBase::eoi_()
{
    if (d_eoi)
        return;

    evpUpdate();                // process available chars in the input
    d_eoi = true;
    resize(0);                  // clear the input buffer
    evpUpdate();                // update an empty buffer

}

🍓 FILES 🍓

bobcat/eoibuf — defines the class interface 📁

👀 SEE ALSO 👀

bobcat(7), eoi(3bobcat)

go read those too, bestie, they're the siblings 🫶

💀 BUGS 💀

None Reported.

and that's the flex of the century, honestly 👑

🎀 BOBCAT PROJECT FILES 🎀

Debian Bobcat project files:

  • libbobcat6 — debian package containing the shared library, changelog and copyright note; 🧚
  • libbobcat-dev — debian package containing the static library, headers, manual pages, and developer info; ✨

🌸 BOBCAT 🌸

Bobcat is an acronym of Brokken's Own Base Classes And Templates. cute name, cute origin story 💖

This is free software, distributed under the terms of the GNU General Public License (GPL). slay 🎉

⭐ AUTHOR ⭐

Frank B. Brokken (f.b.brokken@rug.nl). the icon, the legend, the main character 👑

that's the whole page, bestie — this one ships with libbobcat-dev_6.15.01, dated 2005-2026, and yes it's been serving looks since 2005 💅✨ mwah, go compile something gorgeous 🎀

📦 where this page comes from