1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122
|
/* getline.c -- Replacement for GNU C library function getline
Copyright (C) 1993 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
This program 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
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
/* Written by Jan Brittenson, bson@gnu.ai.mit.edu. */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <sys/types.h>
#include <stdio.h>
#define NDEBUG
#include <assert.h>
#include <stdlib.h>
/* Always add at least this many bytes when extending the buffer. */
#define MIN_CHUNK 64
/* Read up to (and including) a TERMINATOR from STREAM into *LINEPTR
+ OFFSET (and null-terminate it). *LINEPTR is a pointer returned from
malloc (or NULL), pointing to *N characters of space. It is realloc'd
as necessary. Return the number of characters read (not including the
null terminator), or -1 on error or EOF. */
int
getstr (lineptr, n, stream, terminator, offset)
char **lineptr;
size_t *n;
FILE *stream;
char terminator;
int offset;
{
int nchars_avail; /* Allocated but unused chars in *LINEPTR. */
char *read_pos; /* Where we're reading into *LINEPTR. */
int ret;
if (!lineptr || !n || !stream)
return -1;
if (!*lineptr)
{
*n = MIN_CHUNK;
*lineptr = malloc (*n);
if (!*lineptr)
return -1;
}
nchars_avail = *n - offset;
read_pos = *lineptr + offset;
for (;;)
{
register int c = getc (stream);
/* We always want at least one char left in the buffer, since we
always (unless we get an error while reading the first char)
NUL-terminate the line buffer. */
assert(*n - nchars_avail == read_pos - *lineptr);
if (nchars_avail < 1)
{
if (*n > MIN_CHUNK)
*n *= 2;
else
*n += MIN_CHUNK;
nchars_avail = *n + *lineptr - read_pos;
*lineptr = realloc (*lineptr, *n);
if (!*lineptr)
return -1;
read_pos = *n - nchars_avail + *lineptr;
assert(*n - nchars_avail == read_pos - *lineptr);
}
if (c == EOF || ferror (stream))
{
/* Return partial line, if any. */
if (read_pos == *lineptr)
return -1;
else
break;
}
*read_pos++ = c;
nchars_avail--;
if (c == terminator)
/* Return the line. */
break;
}
/* Done - NUL terminate and return the number of chars read. */
*read_pos = '\0';
ret = read_pos - (*lineptr + offset);
return ret;
}
int
getline (lineptr, n, stream)
char **lineptr;
size_t *n;
FILE *stream;
{
return getstr (lineptr, n, stream, '\n', 0);
}
|