NAME¶
tbuf_create, tbuf_destroy, tbuf_copy, tbuf_cat, tbuf_length, tbuf_chars -
manipulate text editor buffer
SYNOPSIS¶
#include <publib.h>
Tbuf *tbuf_create(const char *chars, size_t len);
void tbuf_destroy(Tbuf *tbuf);
Tbuf *tbuf_copy(Tbuf *tbuf, size_t offset, size_tlen);
Tbuf *tbuf_cat(Tbuf *tbuf, Tbuf * tbuf);
size_t tbuf_length(Tbuf *tbuf);
void tbuf_chars(char *chars, Tbuf *tbuf, size_t offset, size_t len);
DESCRIPTION¶
These routines create and manipulate simple text editor buffers, which can also
be thought of as arbitrarily large text strings. The buffers are
one-dimensional (i.e., not automatically divided into lines), and are indexed
with character offsets. They are 8-bit and binary clean, i.e., they may
contain any 8-bit characters, including the zero byte ('\0').
tbuf_create creates a buffer from a C character array, and
tbuf_destroy destroys it. Once it's created, a buffer may not be
modified. Instead, a new buffer needs to be created, using
tbuf_cat and
tbuf_copy. They create the new buffer so that it shares as much memory
as possible with the old buffer, so the immutability does not necessarily
waste memory much. By never changing a buffer, it is rather simple to
implement undo and redo: you only need to keep a list of buffers and display
the suitable one to the user. The caller should remember to call
tbuf_destroy for unnecessary buffers, of course.
tbuf_length returns the number of characters in the buffer.
tbuf_copy copies part of a buffer into a C character array. The array
is
not zero-terminated; the caller must do it himself.
RETURN VALUE¶
tbuf_create,
tbuf_copy, and
tbuf_cat return a pointer to
the new buffer, or NULL if the operation failed.
tbuf_length returns the number of characters in the buffer.
tbuf_destroy and
tbuf_chars return nothing and cannot fail.
SEE ALSO¶
publib(3),
sbuf(3)
AUTHOR¶
Lars Wirzenius, liw@iki.fi.