X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=functions%2Fstdio%2Ffseek.c;h=ab6679bfb7ae590336b16abcb722ecd66971bfc6;hb=33515db12d3cc5e53a8bdea58d2cde299cba2267;hp=f33f250938a0e1cdaaa7fddbe6f971b2e8d52b3a;hpb=e8945ee2684f5c8de0104ea183de2010ae72ffd5;p=pdclib.old

diff --git a/functions/stdio/fseek.c b/functions/stdio/fseek.c
index f33f250..ab6679b 100644
--- a/functions/stdio/fseek.c
+++ b/functions/stdio/fseek.c
@@ -1,6 +1,6 @@
 /* $Id$ */
 
-/* fseek( FILE *, long int, int )
+/* fseek( FILE *, long offset, int )
 
    This file is part of the Public Domain C Library (PDCLib).
    Permission is granted to use, modify, and / or redistribute at will.
@@ -10,21 +10,77 @@
 
 #ifndef REGTEST
 
-int fseek( struct _PDCLIB_file_t * stream, long int offset, int whence )
+#include <_PDCLIB_glue.h>
+
+int fseek( struct _PDCLIB_file_t * stream, long offset, int whence )
 {
-    /* TODO: Implement. */
-    return 0;
+    if ( stream->status & _PDCLIB_FWRITE )
+    {
+        if ( _PDCLIB_flushbuffer( stream ) == EOF )
+        {
+            return EOF;
+        }
+    }
+    stream->status &= ~ _PDCLIB_EOFFLAG;
+    if ( stream->status & _PDCLIB_FRW )
+    {
+        stream->status &= ~ ( _PDCLIB_FREAD | _PDCLIB_FWRITE );
+    }
+    return ( _PDCLIB_seek( stream, offset, whence ) != EOF ) ? 0 : EOF;
 }
 
 #endif
 
 #ifdef TEST
 #include <_PDCLIB_test.h>
+#include <string.h>
 
 int main( void )
 {
-    TESTCASE( NO_TESTDRIVER );
+    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
+