diff options
Diffstat (limited to 'stdio/getdelim.c')
| -rw-r--r-- | stdio/getdelim.c | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/stdio/getdelim.c b/stdio/getdelim.c new file mode 100644 index 0000000000..8047c1fe0c --- /dev/null +++ b/stdio/getdelim.c @@ -0,0 +1,173 @@ +/* Copyright (C) 1991, 1992, 1995 Free Software Foundation, Inc. +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#include <ansidecl.h> +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <limits.h> + +/* Read up to (and including) a TERMINATOR from STREAM into *LINEPTR + (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. Returns the number of characters read (not including the + null terminator), or -1 on error or EOF. */ + +ssize_t +DEFUN(__getdelim, (lineptr, n, terminator, stream), + char **lineptr AND size_t *n AND int terminator AND FILE *stream) +{ + char *line, *p; + size_t size, copy; + + if (!__validfp (stream) || lineptr == NULL || n == NULL) + { + errno = EINVAL; + return -1; + } + + if (ferror (stream)) + return -1; + + /* Make sure we have a line buffer to start with. */ + if (*lineptr == NULL || *n < 2) /* !seen and no buf yet need 2 chars. */ + { +#ifndef MAX_CANON +#define MAX_CANON 256 +#endif + line = realloc (*lineptr, MAX_CANON); + if (line == NULL) + return -1; + *lineptr = line; + *n = MAX_CANON; + } + + line = *lineptr; + size = *n; + + copy = size; + p = line; + + if (stream->__buffer == NULL && stream->__userbuf) + { + /* Unbuffered stream. Not much optimization to do. */ + + while (1) + { + size_t len; + + while (--copy > 0) + { + register int c = getc (stream); + if (c == EOF) + goto lose; + else if ((*p++ = c) == terminator) + goto win; + } + + /* Need to enlarge the line buffer. */ + len = p - line; + size *= 2; + line = realloc (line, size); + if (line == NULL) + goto lose; + *lineptr = line; + *n = size; + p = line + len; + copy = size - len; + } + } + else + { + /* Leave space for the terminating null. */ + --copy; + + if (!stream->__seen || stream->__buffer == NULL || stream->__pushed_back) + { + /* Do one with getc to allocate a buffer. */ + int c = getc (stream); + if (c == EOF) + goto lose; + *p++ = c; + if (c == terminator) + goto win; + --copy; + } + + while (1) + { + size_t i; + char *found; + + i = stream->__get_limit - stream->__bufp; + if (i == 0) + { + /* Refill the buffer. */ + int c = __fillbf (stream); + if (c == EOF) + goto lose; + *p++ = c; + if (c == terminator) + goto win; + --copy; + i = stream->__get_limit - stream->__bufp; + } + + if (i > copy) + i = copy; + + found = (char *) __memccpy ((PTR) p, stream->__bufp, terminator, i); + if (found != NULL) + { + stream->__bufp += found - p; + p = found; + goto win; + } + + stream->__bufp += i; + p += i; + copy -= i; + if (copy == 0) + { + /* Need to enlarge the line buffer. */ + size_t len = p - line; + size *= 2; + line = realloc (line, size); + if (line == NULL) + goto lose; + *lineptr = line; + *n = size; + p = line + len; + copy = size - len; + /* Leave space for the terminating null. */ + --copy; + } + } + } + + lose: + if (p == *lineptr) + return -1; + /* Return a partial line since we got an error in the middle. */ + win: + *p = '\0'; + return p - *lineptr; +} + +weak_alias (__getdelim, getdelim) |