/* linebuffer.c -- read arbitrarily long lines Copyright (C) 1986, 1991, 1998, 1999, 2001, 2003, 2004, 2006, 2007 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, 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ /* Written by Richard Stallman. */ #include #include #include #include #include #include "linebuffer.h" #include "xalloc.h" #if USE_UNLOCKED_IO # include "unlocked-io.h" #endif /* Initialize linebuffer LINEBUFFER for use. */ void initbuffer (struct linebuffer *linebuffer) { memset (linebuffer, 0, sizeof *linebuffer); } struct linebuffer * readlinebuffer (struct linebuffer *linebuffer, FILE *stream) { return readlinebuffer_delim (linebuffer, stream, '\n'); } /* Read an arbitrarily long line of text from STREAM into LINEBUFFER. Consider lines to be terminated by DELIMITER. Keep the delimiter; append DELIMITER if it's the last line of a file that ends in a character other than DELIMITER. Do not NUL-terminate. Therefore the stream can contain NUL bytes, and the length (including the delimiter) is returned in linebuffer->length. Return NULL when stream is empty. Return NULL and set errno upon error; callers can distinguish this case from the empty case by invoking ferror (stream). Otherwise, return LINEBUFFER. */ struct linebuffer * readlinebuffer_delim (struct linebuffer *linebuffer, FILE *stream, char delimiter) { int c; char *buffer = linebuffer->buffer; char *p = linebuffer->buffer; char *end = buffer + linebuffer->size; /* Sentinel. */ if (feof (stream)) return NULL; do { c = getc (stream); if (c == EOF) { if (p == buffer || ferror (stream)) return NULL; if (p[-1] == delimiter) break; c = delimiter; } if (p == end) { size_t oldsize = linebuffer->size; buffer = x2realloc (buffer, &linebuffer->size); p = buffer + oldsize; linebuffer->buffer = buffer; end = buffer + linebuffer->size; } *p++ = c; } while (c != delimiter); linebuffer->length = p - buffer; return linebuffer; } /* Free the buffer that was allocated for linebuffer LINEBUFFER. */ void freebuffer (struct linebuffer *linebuffer) { free (linebuffer->buffer); }