source: MondoRescue/branches/2.2.5/mindi-busybox/libbb/get_line_from_file.c@ 1765

/* vi: set sw=4 ts=4: */
/*
 * Utility routines.
 *
 * Copyright (C) 2005, 2006 Rob Landley <rob@landley.net>
 * Copyright (C) 2004 Erik Andersen <andersen@codepoet.org>
 * Copyright (C) 2001 Matt Krai
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

#include "libbb.h"

/* This function reads an entire line from a text file, up to a newline
 * or NUL byte, inclusive.  It returns a malloc'ed char * which must be
 * stored and free'ed by the caller.  If end is NULL '\n' isn't considered
 * end of line.  If end isn't NULL, length of the chunk read is stored in it.
 * Return NULL if EOF/error */

char *bb_get_chunk_from_file(FILE *file, int *end)
{
    int ch;
    int idx = 0;
    char *linebuf = NULL;
    int linebufsz = 0;

    while ((ch = getc(file)) != EOF) {
        /* grow the line buffer as necessary */
        if (idx >= linebufsz) {
            linebufsz += 80;
            linebuf = xrealloc(linebuf, linebufsz);
        }
        linebuf[idx++] = (char) ch;
        if (!ch || (end && ch == '\n'))
            break;
    }
    if (end)
        *end = idx;
    if (linebuf) {
        // huh, does fgets discard prior data on error like this?
        // I don't think so....
        //if (ferror(file)) {
        //  free(linebuf);
        //  return NULL;
        //}
        linebuf = xrealloc(linebuf, idx+1);
        linebuf[idx] = '\0';
    }
    return linebuf;
}

/* Get line, including trailing \n if any */
char *xmalloc_fgets(FILE *file)
{
    int i;

    return bb_get_chunk_from_file(file, &i);
}

/* Get line.  Remove trailing \n */
char *xmalloc_getline(FILE *file)
{
    int i;
    char *c = bb_get_chunk_from_file(file, &i);

    if (i && c[--i] == '\n')
        c[i] = '\0';

    return c;
}