-// ----------------------------------------------------------------------------
-// $Id$
-// ----------------------------------------------------------------------------
-// Public Domain C Library - http://pdclib.sourceforge.net
-// This code is Public Domain. Use, modify, and redistribute at will.
-// ----------------------------------------------------------------------------
-
-FILE * fopen( const char * restrict filename, const char * restrict mode ) { /* TODO */ };
+/* $Id$ */
+
+/* fopen( const char *, const char * )
+
+ This file is part of the Public Domain C Library (PDCLib).
+ Permission is granted to use, modify, and / or redistribute at will.
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#ifndef REGTEST
+#include <_PDCLIB_glue.h>
+
+static FILE * _PDCLIB_filelist = NULL;
+
+/* Helper function that parses the C-style mode string passed to fopen() into
+ the PDCLib flags.FREAD, FWRITE, FAPPEND, FRW (read-write) and FBIN (
+ mode).
+*/
+static unsigned int filemode( char const * const mode )
+{
+ int rc = 0;
+ switch ( mode[0] )
+ {
+ case 'r':
+ rc |= _PDCLIB_FREAD;
+ break;
+ case 'w':
+ rc |= _PDCLIB_FWRITE;
+ break;
+ case 'a':
+ rc |= _PDCLIB_FAPPEND;
+ break;
+ default:
+ /* Other than read, write, or append - invalid */
+ return 0;
+ }
+ for ( size_t i = 1; i < 4; ++i )
+ {
+ switch ( mode[1] )
+ {
+ case '+':
+ if ( rc & _PDCLIB_FRW ) return 0; /* Duplicates are invalid */
+ rc |= _PDCLIB_FRW;
+ break;
+ case 'b':
+ if ( rc & _PDCLIB_FBIN ) return 0; /* Duplicates are invalid */
+ rc |= _PDCLIB_FBIN;
+ break;
+ case '\0':
+ /* End of mode */
+ return rc;
+ default:
+ /* Other than read/write or binary - invalid. */
+ return 0;
+ }
+ }
+ /* Longer than three chars - invalid. */
+ return 0;
+}
+
+FILE * fopen( const char * _PDCLIB_restrict filename, const char * _PDCLIB_restrict mode )
+{
+ FILE * rc;
+ if ( mode == NULL || filename == NULL || filename[0] == '\0' )
+ {
+ /* Mode or filename invalid */
+ return NULL;
+ }
+ if ( ( rc = calloc( 1, sizeof( FILE ) ) ) == NULL )
+ {
+ /* no memory for another FILE */
+ return NULL;
+ }
+ if ( ( rc->status = filemode( mode ) ) == 0 ) goto fail; /* invalid mode */
+ rc->handle = _PDCLIB_open( filename, rc->status );
+ if ( rc->handle == _PDCLIB_NOHANDLE ) goto fail; /* OS open() failed */
+
+ /* Adding to list of open files */
+ rc->next = _PDCLIB_filelist;
+ _PDCLIB_filelist = rc;
+ /* Setting buffer. TODO: Check for unbuffered? */
+ if ( ( rc->buffer = malloc( BUFSIZ ) ) == NULL ) goto fail;
+ /* TODO: Setting mbstate */
+ return rc;
+fail:
+ free( rc );
+ return NULL;
+}
+
+#endif
+
+#ifdef TEST
+#include <_PDCLIB_test.h>
+
+int main( void )
+{
+ TESTCASE( NO_TESTDRIVER );
+ return TEST_RESULTS;
+}
+
+#endif