-lite: The missing C-lib functions

Libite, or -lite, is a light-weight library of utility functions and missing C library functions. It holds a many functions previously found in Finit, complemented with a few of my own and some from the OpenBSD project, most notably their famous string functions: strlcpy(3) and strlcat(3). It also holds the very useful *BSD linked list API sys/queue.h, which is a much more up to date version than GLIBC carries! GLIBC does not have the _SAFE macros for traversing lists while deleting/freeing nodes.

Helper Macros

• blkdev(dev)

Create block device

• chardev(dev)

Create character device

• erase(path)

  Erase file/directory with remove(). Errors on stderr

• makedir(path)

  Create directory, like mkdir(). Errors on stderr

• makefifo(path)

  Create a FIFO, like mkfifo(). Errors on stderr

• touch(path)

  Create a file, or update mtime. Errors on stderr

• S_ISEXEC(mode_t m)

Mysteriously missing from GLIBC

• UNUSED(var)

Shorter and more readable version of var __attribute__ ((unused))

Generic Functions

• chomp(str)

  Perl like chomp function, chop off last char if newline.

• copyfile(src, dst, len, symlink)

  Like the shell cp(1) and dd(1), can also create symlinks.

• dir(dir, ext, filter, list, strip)

  Wrapper for scandir() with optional filter. Returns a list of names: files and directories that must be freed after use. See the unit test at the bottom for an example.

• fcopyfile(src, dst)

  Like copyfile() but uses already open FILE * pointers. Copies from current file positions to current file positions until EOF.

• fexist(file)

  Check for the existance of a file, returns True(1) or False(0).

• fisdir(path)

  Check for the existance of a directory, returns True(1) or False(0).

• fmode(file)

  Returns the mode_t bits of a file or directory.

• fsendfile(src, dst, len)

  Copy data between file streams, very similar to fcopyfile(), but dst is allowed to be NULL to be able to read and discard len bytes from src.

• makepath(dir)

  Create all components of the specified directory.

• mkpath(dir, mode)

  Like makepath(), but also takes a mode_t permission mode argument.

• movefile(src, dst)

  Like copyfile(), but renames src to dst, or recreates symlink with the dst name. On successful operation the source is removed and the function returns POSIX OK (0).

• pidfile(basename)

  Write a daemon pid file. Creates a pidfile in _PATH_VARRUN using either basename or, if basename is NULL, __progname. The file name has the form /var/run/basename.pid.

  Use this function to create a pid file for your daemon when it is ready to receive signals. A client application may poll for the existence of this file, so make sure to have your signal handlers properly setup before calling this function.

  The pidfile is removed when the program exits, using an atexit() handler. However, depending on how the program terminates the file may still exist even though the program is no longer running. This is only a problem for clients.

• pidfile_read(pidfile)

  Read PID from pid file created by pidfile().

• pidfile_signal(pidfile, signal)

  Send signal to PID found in pid file created by pidfile().

• rsync(src, dst, delete, *filter())

  Very simple rsync() to copy files files and directories recursively.

• tempfile()

  Secure replacement for tmpfile(). Creates an invisible temporary file in /tmp that is removed when the returned FILE pointer is closed. Note: Requires Linux v3.11, or later.

OpenBSD Functions

The following are the popular OpenBSD string functions.

• strlcpy(dst, src, len)
• strlcat(dst, src, len)
• strtonum()
• sys/queue.h API

TODO

• Improve documentation, possibly use kdoc or gdoc2 to generate docs from API.