PDCLIB-7: Add _PDCLIB_ftell64 to give us full precision file positioning information...

[pdclib] / functions / stdio / fseek.c

diff --git a/functions/stdio/fseek.c b/functions/stdio/fseek.c
index ab6679bfb7ae590336b16abcb722ecd66971bfc6..8e10c2ba007f49cd599c7c5fc62275995076e729 100644 (file)
--- a/functions/stdio/fseek.c
+++ b/functions/stdio/fseek.c
@@ -12,8 +12,9 @@
 
 #include <_PDCLIB_glue.h>
 
-int fseek( struct _PDCLIB_file_t * stream, long offset, int whence )
+int fseek( struct _PDCLIB_file_t * stream, long loffset, int whence )
 {
+    _PDCLIB_int64_t offset = loffset;
     if ( stream->status & _PDCLIB_FWRITE )
     {
         if ( _PDCLIB_flushbuffer( stream ) == EOF )
@@ -26,6 +27,13 @@ int fseek( struct _PDCLIB_file_t * stream, long offset, int whence )
     {
         stream->status &= ~ ( _PDCLIB_FREAD | _PDCLIB_FWRITE );
     }
+
+    if ( whence == SEEK_CUR )
+    {
+        whence  = SEEK_SET;
+        offset += _PDCLIB_ftell64( stream );
+    }
+
     return ( _PDCLIB_seek( stream, offset, whence ) != EOF ) ? 0 : EOF;
 }
 
@@ -75,6 +83,16 @@ int main( void )
     TESTCASE( ftell( fh ) == 2 );
     TESTCASE( fseek( fh, 2, SEEK_SET ) == 0 );
     TESTCASE( fgetc( fh ) == teststring[2] );
+    /* PDCLIB-7: Check that we handle the underlying file descriptor correctly
+     *           in the SEEK_CUR case */
+    TESTCASE( fseek( fh, 10, SEEK_SET ) == 0 );
+    TESTCASE( ftell( fh ) == 10l );
+    TESTCASE( fseek( fh, 0, SEEK_CUR ) == 0 );
+    TESTCASE( ftell( fh ) == 10l );
+    TESTCASE( fseek( fh, 2, SEEK_CUR ) == 0 );
+    TESTCASE( ftell( fh ) == 12l );
+    TESTCASE( fseek( fh, -1, SEEK_CUR ) == 0 );
+    TESTCASE( ftell( fh ) == 11l );
     /* Checking error handling */
     TESTCASE( fseek( fh, -5, SEEK_SET ) == -1 );
     TESTCASE( fseek( fh, 0, SEEK_END ) == 0 );