sortix-mirror/libc/stdio/getdelim.cpp

80 lines
2.1 KiB
C++

/*******************************************************************************
Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2014.
This file is part of the Sortix C Library.
The Sortix C Library is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
The Sortix C Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
stdio/getdelim.cpp
Delimited string input.
*******************************************************************************/
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
extern "C" ssize_t getdelim(char** lineptr, size_t* n, int delim, FILE* fp)
{
if ( !lineptr || (*lineptr && !n) || !fp )
return errno = EINVAL, -1;
const size_t DEFAULT_BUFSIZE = 32UL;
bool malloced = !*lineptr;
if ( malloced )
*lineptr = (char*) malloc(DEFAULT_BUFSIZE);
if ( !*lineptr )
return -1;
size_t bufsize = malloced ? DEFAULT_BUFSIZE : *n;
if ( n )
*n = bufsize;
ssize_t written = 0;
int c;
flockfile(fp);
do
{
if ( (c = getc_unlocked(fp)) == EOF )
{
if ( written )
break;
else
goto cleanup;
}
if ( bufsize <= (size_t) written + 1UL )
{
size_t newbufsize = 2UL * bufsize;
char* newbuf = (char*) realloc(*lineptr, newbufsize);
if ( !newbuf )
goto cleanup;
bufsize = newbufsize;
if ( n )
*n = bufsize;
*lineptr = newbuf;
}
(*lineptr)[written++] = c;
} while ( c != delim );
funlockfile(fp);
(*lineptr)[written] = 0;
return written;
cleanup:
funlockfile(fp);
if ( malloced )
{
free(*lineptr);
*lineptr = NULL;
}
return -1;
}