1 files changed, 173 insertions, 0 deletions
diff --git a/filter.c b/filter.c
new file mode 100644
index 0000000..11d8158
--- /dev/null
+++ b/filter.c
@@ -0,0 +1,173 @@
+/*  Copyright 1996,1997,1999,2001-2003,2008,2009 Alain Knaff.
+ *  This file is part of mtools.
+ *
+ *  Mtools 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 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  Mtools 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 Mtools.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "sysincludes.h"
+#include "msdos.h"
+#include "mtools.h"
+#include "codepage.h"
+
+typedef struct Filter_t {
+	Class_t *Class;
+	int refs;
+	Stream_t *Next;
+	Stream_t *Buffer;
+
+	int dospos;
+	int unixpos;
+	int mode;
+	int rw;
+	int lastchar;
+	/* int convertCharset; */
+} Filter_t;
+
+#define F_READ 1
+#define F_WRITE 2
+
+/* read filter filters out messy dos' bizarre end of lines and final 0x1a's */
+
+static int read_filter(Stream_t *Stream, char *buf, mt_off_t iwhere, size_t len)
+{
+	DeclareThis(Filter_t);
+	int i,j,ret;
+	unsigned char newchar;
+
+	off_t where = truncBytes32(iwhere);
+
+	if ( where != This->unixpos ){
+		fprintf(stderr,"Bad offset\n");
+		exit(1);
+	}
+	if (This->rw == F_WRITE){
+		fprintf(stderr,"Change of transfer direction!\n");
+		exit(1);
+	}
+	This->rw = F_READ;
+	
+	ret = READS(This->Next, buf, (mt_off_t) This->dospos, len);
+	if ( ret < 0 )
+		return ret;
+
+	j = 0;
+	for (i=0; i< ret; i++){
+		if ( buf[i] == '\r' )
+			continue;
+		if (buf[i] == 0x1a)
+			break;
+		newchar = buf[i];
+		/*
+		if (This->convertCharset) newchar = contents_to_unix(newchar);
+		*/
+		This->lastchar = buf[j++] = newchar;
+	}
+
+	This->dospos += i;
+	This->unixpos += j;
+	return j;
+}
+
+static int write_filter(Stream_t *Stream, char *buf, mt_off_t iwhere,
+						size_t len)
+{
+	DeclareThis(Filter_t);
+	unsigned int i,j;
+	int ret;
+	char buffer[1025];
+	unsigned char newchar;
+	
+	off_t where = truncBytes32(iwhere);
+
+	if(This->unixpos == -1)
+		return -1;
+
+	if (where != This->unixpos ){
+		fprintf(stderr,"Bad offset\n");
+		exit(1);
+	}
+	
+	if (This->rw == F_READ){
+		fprintf(stderr,"Change of transfer direction!\n");
+		exit(1);
+	}
+	This->rw = F_WRITE;
+
+	j=i=0;
+	while(i < 1024 && j < len){
+		if (buf[j] == '\n' ){
+			buffer[i++] = '\r';
+			buffer[i++] = '\n';
+			j++;
+			continue;
+		}
+		newchar = buf[j++];
+		/*
+		if (This->convertCharset) newchar = to_dos(newchar);
+		*/
+		buffer[i++] = newchar;
+	}
+	This->unixpos += j;
+
+	ret = force_write(This->Next, buffer, (mt_off_t) This->dospos, i);
+	if(ret >0 )
+		This->dospos += ret;
+	if ( ret != (signed int) i ){
+		/* no space on target file ? */
+		This->unixpos = -1;
+		return -1;
+	}
+	return j;
+}
+
+static int free_filter(Stream_t *Stream)
+{
+	DeclareThis(Filter_t);
+	char buffer=0x1a;
+
+	/* write end of file */
+	if (This->rw == F_WRITE)
+		return force_write(This->Next, &buffer, (mt_off_t) This->dospos, 1);
+	else
+		return 0;
+}
+
+static Class_t FilterClass = {
+	read_filter,
+	write_filter,
+	0, /* flush */
+	free_filter,
+	0, /* set geometry */
+	get_data_pass_through,
+	0
+};
+
+Stream_t *open_filter(Stream_t *Next, int convertCharset UNUSEDP)
+{
+	Filter_t *This;
+
+	This = New(Filter_t);
+	if (!This)
+		return NULL;
+	This->Class = &FilterClass;
+	This->dospos = This->unixpos = This->rw = 0;
+	This->Next = Next;
+	This->refs = 1;
+	This->Buffer = 0;
+	/*
+	  This->convertCharset = convertCharset;
+	*/
+
+	return (Stream_t *) This;
+}