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author | Jim Meyering <jim@meyering.net> | 1995-09-19 14:30:59 +0000 |
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committer | Jim Meyering <jim@meyering.net> | 1995-09-19 14:30:59 +0000 |
commit | 3ed71a2fdd0ad2baa3137c06327ff993bcd07a29 (patch) | |
tree | 3d265bacb6759270d201968317efe25701aa8d26 /lib | |
parent | 0e15d57a89324fb7f68ec8c5b41656b09ff0a8fd (diff) | |
download | coreutils-3ed71a2fdd0ad2baa3137c06327ff993bcd07a29.tar.xz |
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Diffstat (limited to 'lib')
-rw-r--r-- | lib/getline.c | 126 | ||||
-rw-r--r-- | lib/getline.h | 17 |
2 files changed, 143 insertions, 0 deletions
diff --git a/lib/getline.c b/lib/getline.c new file mode 100644 index 000000000..c69946148 --- /dev/null +++ b/lib/getline.c @@ -0,0 +1,126 @@ +/* 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> + +#if STDC_HEADERS +#include <stdlib.h> +#else +char *malloc (), *realloc (); +#endif + +/* 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 < 2) + { + 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); +} diff --git a/lib/getline.h b/lib/getline.h new file mode 100644 index 000000000..c71aea1f3 --- /dev/null +++ b/lib/getline.h @@ -0,0 +1,17 @@ +#ifndef _getline_h_ +#define _getline_h_ 1 + +#include <stdio.h> + +#ifndef __P +#if defined (__GNUC__) || (defined (__STDC__) && __STDC__) +#define __P(args) args +#else +#define __P(args) () +#endif /* GCC. */ +#endif /* Not __P. */ + +int + getline __P ((char **_lineptr, size_t *_n, FILE *_stream)); + +#endif /* _getline_h_ */ |