X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=functions%2Fstdio%2Ffseek.c;h=ab6679bfb7ae590336b16abcb722ecd66971bfc6;hb=a7a8d2f1c85c2d7760d4d3479e90466cc3a81b04;hp=9a945477445c4642291748ba17cd86cd97fe4855;hpb=526e9954c39f30819e421cb74e82aa59d5a41013;p=pdclib

diff --git a/functions/stdio/fseek.c b/functions/stdio/fseek.c
index 9a94547..ab6679b 100644
--- a/functions/stdio/fseek.c
+++ b/functions/stdio/fseek.c
@@ -26,17 +26,59 @@ int fseek( struct _PDCLIB_file_t * stream, long offset, int whence )
     {
         stream->status &= ~ ( _PDCLIB_FREAD | _PDCLIB_FWRITE );
     }
-    return ( _PDCLIB_seek( stream, offset, whence ) == offset ) ? 0 : EOF;
+    return ( _PDCLIB_seek( stream, offset, whence ) != EOF ) ? 0 : EOF;
 }
 
 #endif
 
 #ifdef TEST
 #include <_PDCLIB_test.h>
+#include <string.h>
 
 int main( void )
 {
-    /* Testing covered by ftell.c */
+    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;
 }