X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=functions%2Fstdio%2Ffseek.c;h=167c18693800903bc71fb3f315363752ed96c0b5;hb=b1fc26afebd4d557ff89a44bc21767a8704c3809;hp=61dbc4fc7c9799a4c46c5ecd03c256b54fe7bd10;hpb=1d9d92ba957a0b8307c9a65c35867fde68e6533b;p=pdclib

diff --git a/functions/stdio/fseek.c b/functions/stdio/fseek.c
index 61dbc4f..167c186 100644
--- a/functions/stdio/fseek.c
+++ b/functions/stdio/fseek.c
@@ -1,65 +1,84 @@
-/* ----------------------------------------------------------------------------
- * $Id$
- * ----------------------------------------------------------------------------
- * Public Domain C Library - http://pdclib.sourceforge.net
- * This code is Public Domain. Use, modify, and redistribute at will.
- * --------------------------------------------------------------------------*/
+/* fseek( FILE *, long, int )
 
-int fseek( FILE * stream, long offset, int mode ) { /* TODO */ };
+   This file is part of the Public Domain C Library (PDCLib).
+   Permission is granted to use, modify, and / or redistribute at will.
+*/
 
-/* PDPC code - unreviewed
-Read the note in fopen.c.
-{
-    long newpos;
-#ifdef __OS2__
-    ULONG retpos;
-    APIRET rc;
-#endif
+#include <stdio.h>
 
-    if (stream->mode == __WRITE_MODE)
-    {
-        fflush(stream);
-    }
-    if (whence == SEEK_SET)
-    {
-        newpos = offset;
-    }
-    else if (whence == SEEK_CUR)
+#ifndef REGTEST
+
+#include <_PDCLIB_glue.h>
+
+int fseek( struct _PDCLIB_file_t * stream, long offset, int whence )
+{
+    if ( stream->status & _PDCLIB_FWRITE )
     {
-        newpos = offset + stream->bufStartR + (stream->upto - stream->fbuf);
+        if ( _PDCLIB_flushbuffer( stream ) == EOF )
+        {
+            return EOF;
+        }
     }
-    if ((newpos > stream->bufStartR)
-        && (newpos < (stream->bufStartR + (stream->endbuf - stream->fbuf)))
-        && stream->update)
+    stream->status &= ~ _PDCLIB_EOFFLAG;
+    if ( stream->status & _PDCLIB_FRW )
     {
-        stream->upto = stream->fbuf + (size_t)(newpos - stream->bufStartR);
+        stream->status &= ~ ( _PDCLIB_FREAD | _PDCLIB_FWRITE );
     }
-    else
-    {
-#ifdef __OS2__
-        rc = DosSetFilePtr(stream->hfile, newpos, FILE_BEGIN, &retpos);
-        if ((rc != 0) || (retpos != newpos))
-        {
-            errno = rc;
-            return (-1);
-        }
-        else
-        {
-            stream->endbuf = stream->fbuf + stream->szfbuf;
-            stream->upto = stream->endbuf;
-            stream->bufStartR = newpos - stream->szfbuf;
-        }
-#endif
-#ifdef __MSDOS
-        __seek(stream->hfile, newpos, whence);
-        stream->endbuf = stream->fbuf + stream->szfbuf;
-        stream->upto = stream->endbuf;
-        stream->bufStartR = newpos - stream->szfbuf;
+    return ( _PDCLIB_seek( stream, offset, whence ) != EOF ) ? 0 : EOF;
+}
+
 #endif
-    }
-    stream->quickBin = 0;
-    stream->quickText = 0;
-    stream->ungetCh = -1;
-    return (0);
+
+#ifdef TEST
+#include <_PDCLIB_test.h>
+#include <string.h>
+
+int main( void )
+{
+    FILE * fh;
+    TESTCASE( ( fh = tmpfile() ) != NULL );
+    TESTCASE( fwrite( teststring, 1, strlen( teststring ), fh ) == strlen( teststring ) );
+    /* General functionality */
+    TESTCASE( fseek( fh, -1, SEEK_END ) == 0  );
+    TESTCASE( (size_t)ftell( fh ) == strlen( teststring ) - 1 );
+    TESTCASE( fseek( fh, 0, SEEK_END ) == 0 );
+    TESTCASE( (size_t)ftell( fh ) == strlen( teststring ) );
+    TESTCASE( fseek( fh, 0, SEEK_SET ) == 0 );
+    TESTCASE( ftell( fh ) == 0 );
+    TESTCASE( fseek( fh, 5, SEEK_CUR ) == 0 );
+    TESTCASE( ftell( fh ) == 5 );
+    TESTCASE( fseek( fh, -3, SEEK_CUR ) == 0 );
+    TESTCASE( ftell( fh ) == 2 );
+    /* Checking behaviour around EOF */
+    TESTCASE( fseek( fh, 0, SEEK_END ) == 0 );
+    TESTCASE( ! feof( fh ) );
+    TESTCASE( fgetc( fh ) == EOF );
+    TESTCASE( feof( fh ) );
+    TESTCASE( fseek( fh, 0, SEEK_END ) == 0 );
+    TESTCASE( ! feof( fh ) );
+    /* Checking undo of ungetc() */
+    TESTCASE( fseek( fh, 0, SEEK_SET ) == 0 );
+    TESTCASE( fgetc( fh ) == teststring[0] );
+    TESTCASE( fgetc( fh ) == teststring[1] );
+    TESTCASE( fgetc( fh ) == teststring[2] );
+    TESTCASE( ftell( fh ) == 3 );
+    TESTCASE( ungetc( teststring[2], fh ) == teststring[2] );
+    TESTCASE( ftell( fh ) == 2 );
+    TESTCASE( fgetc( fh ) == teststring[2] );
+    TESTCASE( ftell( fh ) == 3 );
+    TESTCASE( ungetc( 'x', fh ) == 'x' );
+    TESTCASE( ftell( fh ) == 2 );
+    TESTCASE( fgetc( fh ) == 'x' );
+    TESTCASE( ungetc( 'x', fh ) == 'x' );
+    TESTCASE( ftell( fh ) == 2 );
+    TESTCASE( fseek( fh, 2, SEEK_SET ) == 0 );
+    TESTCASE( fgetc( fh ) == teststring[2] );
+    /* Checking error handling */
+    TESTCASE( fseek( fh, -5, SEEK_SET ) == -1 );
+    TESTCASE( fseek( fh, 0, SEEK_END ) == 0 );
+    TESTCASE( fclose( fh ) == 0 );
+    return TEST_RESULTS;
 }
-*/
+
+#endif
+