Added fclose().

[pdclib] / functions / stdio / fopen.c

diff --git a/functions/stdio/fopen.c b/functions/stdio/fopen.c
index 04020d94645a1f52dee6f3bd88da52c0e91f4850..2abb66407bb9bb7e80eb53dcecd0740148a2697e 100644 (file)
--- a/functions/stdio/fopen.c
+++ b/functions/stdio/fopen.c
@@ -1,8 +1,128 @@
-// ----------------------------------------------------------------------------
-// $Id$
-// ----------------------------------------------------------------------------
-// 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>
+
+/* FIXME: This approach is a possible attack vector. */
+struct _PDCLIB_file_t * _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 (binary
+   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[i] )
+        {
+            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;
+}
+
+struct _PDCLIB_file_t * fopen( const char * _PDCLIB_restrict filename, const char * _PDCLIB_restrict mode )
+{
+    struct _PDCLIB_file_t * rc;
+    if ( mode == NULL || filename == NULL || filename[0] == '\0' )
+    {
+        /* Mode or filename invalid */
+        return NULL;
+    }
+    if ( ( rc = calloc( 1, sizeof( struct _PDCLIB_file_t ) ) ) == 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, and mark as internal. TODO: Check for unbuffered? */
+    if ( ( rc->buffer = malloc( BUFSIZ ) ) == NULL ) goto fail;
+    rc->status |= _PDCLIB_LIBBUFFER;
+    /* TODO: Setting mbstate */
+    return rc;
+fail:
+    free( rc );
+    return NULL;
+}
+
+#endif
+
+#ifdef TEST
+#include <_PDCLIB_test.h>
+
+int main( void )
+{
+    TESTCASE( filemode( "r" ) == _PDCLIB_FREAD );
+    TESTCASE( filemode( "w" ) == _PDCLIB_FWRITE );
+    TESTCASE( filemode( "a" ) == _PDCLIB_FAPPEND );
+    TESTCASE( filemode( "r+" ) == ( _PDCLIB_FREAD | _PDCLIB_FRW ) );
+    TESTCASE( filemode( "w+" ) == ( _PDCLIB_FWRITE | _PDCLIB_FRW ) );
+    TESTCASE( filemode( "a+" ) == ( _PDCLIB_FAPPEND | _PDCLIB_FRW ) );
+    TESTCASE( filemode( "rb" ) == ( _PDCLIB_FREAD | _PDCLIB_FBIN ) );
+    TESTCASE( filemode( "wb" ) == ( _PDCLIB_FWRITE | _PDCLIB_FBIN ) );
+    TESTCASE( filemode( "ab" ) == ( _PDCLIB_FAPPEND | _PDCLIB_FBIN ) );
+    TESTCASE( filemode( "r+b" ) == ( _PDCLIB_FREAD | _PDCLIB_FRW | _PDCLIB_FBIN ) );
+    TESTCASE( filemode( "w+b" ) == ( _PDCLIB_FWRITE | _PDCLIB_FRW | _PDCLIB_FBIN ) );
+    TESTCASE( filemode( "a+b" ) == ( _PDCLIB_FAPPEND | _PDCLIB_FRW | _PDCLIB_FBIN ) );
+    TESTCASE( filemode( "rb+" ) == ( _PDCLIB_FREAD | _PDCLIB_FRW | _PDCLIB_FBIN ) );
+    TESTCASE( filemode( "wb+" ) == ( _PDCLIB_FWRITE | _PDCLIB_FRW | _PDCLIB_FBIN ) );
+    TESTCASE( filemode( "ab+" ) == ( _PDCLIB_FAPPEND | _PDCLIB_FRW | _PDCLIB_FBIN ) );
+    TESTCASE( fopen( NULL, NULL ) == NULL );
+    TESTCASE( fopen( NULL, "w" ) == NULL );
+    TESTCASE( fopen( "", NULL ) == NULL );
+    TESTCASE( fopen( "", "w" ) == NULL );
+    TESTCASE( fopen( "foo", "" ) == NULL );
+    TESTCASE( fopen( "testfile", "wq" ) == NULL ); /* Illegal mode */
+    TESTCASE( fopen( "testfile", "wr" ) == NULL ); /* Illegal mode */
+    TESTCASE( fopen( "testfile", "w" ) != NULL );
+    system( "rm testfile" );
+    return TEST_RESULTS;
+}
+
+#endif