// "cfa -E fstream.c > fstream_out.c"
// "cfa -c -o fstream.o fstream.c"

#include "fstream.h"

extern "C" {
#include <stdio.h>
#include <stdlib.h>
}

struct ofstream {
    FILE *file;
    int fail;
};

ofstream * write( ofstream *os, const char *data, streamsize_type size ) {
    if( !os->fail ) {
	fwrite( data, size, 1, os->file );
	os->fail = ferror( os->file );
    }
    return os;
}

int fail( ofstream *os ) {
    return os->fail;
}

static ofstream * make_ofstream() {
    ofstream *new_stream = malloc( sizeof( ofstream ) );
    new_stream->fail = 0;
    return new_stream;
}

ofstream * ofstream_stdout() {
    ofstream *stdout_stream = make_ofstream();
    stdout_stream->file = stdout;
    return stdout_stream;
}

ofstream * ofstream_stderr() {
    ofstream *stderr_stream = make_ofstream();
    stderr_stream->file = stderr;
    return stderr_stream;
}

ofstream * ofstream_fromfile( const char *name ) {
    ofstream *file_stream = make_ofstream();
    file_stream->file = fopen( name, "w" );
    file_stream->fail = file_stream->file == 0;
    return file_stream;
}

void ofstream_close( ofstream *os ) {
    if( os->file != stdout && os->file != stderr ) {
	os->fail = fclose( os->file );
    }
    free( os );
}

struct ifstream {
    FILE *file;
    int fail;
    int eof;
};

ifstream * read( ifstream *is, char *data, streamsize_type size ) {
    if( !is->fail && !is->eof ) {
	fread( data, size, 1, is->file );
	is->fail = ferror( is->file );
	is->eof = feof( is->file );
    }
    return is;
}
  
ifstream *unread( ifstream *is, char c ) {
    if( !is->fail ) {
	if( EOF == ungetc( c, is->file ) ) {
	    is->fail = 1;
	}
    }
    return is;
}

int fail( ifstream *is ) {
    return is->fail;
}

int eof( ifstream *is ) {
    return is->eof;
}

static ifstream * make_ifstream() {
    ifstream *new_stream = malloc( sizeof( ifstream ) );
    new_stream->fail = 0;
    new_stream->eof = 0;
    return new_stream;
}

ifstream * ifstream_stdin() {
    ifstream *stdin_stream = make_ifstream();
    stdin_stream->file = stdin;
    return stdin_stream;
}

ifstream * ifstream_fromfile( const char *name ) {
    ifstream *file_stream = make_ifstream();
    file_stream->file = fopen( name, "r" );
    file_stream->fail = file_stream->file == 0;
    return file_stream;
}