fwrite: output line buffered content as we go along

[pdclib.old] / functions / stdio / fwrite.c

diff --git a/functions/stdio/fwrite.c b/functions/stdio/fwrite.c
index 4eece021380b9a43ed0925fa3a9f2c6784e1cca9..d0efadb207df354eabdca050be5819c1756a370d 100644 (file)
--- a/functions/stdio/fwrite.c
+++ b/functions/stdio/fwrite.c
@@ -1,8 +1,80 @@
-// ----------------------------------------------------------------------------
-// $Id$
-// ----------------------------------------------------------------------------
-// Public Domain C Library - http://pdclib.sourceforge.net
-// This code is Public Domain. Use, modify, and redistribute at will.
-// ----------------------------------------------------------------------------
-
-size_t fwrite( const void * restrict ptr, size_t size, size_t nelem, FILE * restrict stream ) { /* TODO */ };
+/* $Id$ */
+
+/* fwrite( const void *, size_t, size_t, FILE * )
+
+   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>
+
+#ifndef REGTEST
+#include <_PDCLIB_io.h>
+#include <_PDCLIB_glue.h>
+
+#include <stdbool.h>
+#include <string.h>
+
+size_t _PDCLIB_fwrite_unlocked( const void *restrict vptr,
+               size_t size, size_t nmemb,
+               FILE * _PDCLIB_restrict stream )
+{
+    if ( _PDCLIB_prepwrite( stream ) == EOF )
+    {
+        return 0;
+    }
+
+    const char *restrict ptr = vptr;
+    size_t nmemb_i;
+    for ( nmemb_i = 0; nmemb_i < nmemb; ++nmemb_i )
+    {
+        for ( size_t size_i = 0; size_i < size; ++size_i )
+        {
+            char c = ptr[ nmemb_i * size + size_i ];
+            stream->buffer[ stream->bufidx++ ] = c;
+
+            if ( stream->bufidx == stream->bufsize || ( c == '\n' && stream->status & _IOLBF ) )
+            {
+                if ( _PDCLIB_flushbuffer( stream ) == EOF )
+                {
+                    /* Returning number of objects completely buffered */
+                    return nmemb_i;
+                }
+            }
+        }
+
+        if ( stream->status & _IONBF )
+        {
+            if ( _PDCLIB_flushbuffer( stream ) == EOF )
+            {
+                /* Returning number of objects completely buffered */
+                return nmemb_i;
+            }
+        }
+    }
+    return nmemb_i;
+}
+
+size_t fwrite( const void * _PDCLIB_restrict ptr,
+               size_t size, size_t nmemb,
+               FILE * _PDCLIB_restrict stream )
+{
+    _PDCLIB_flockfile( stream );
+    size_t r = _PDCLIB_fwrite_unlocked( ptr, size, nmemb, stream );
+    _PDCLIB_funlockfile( stream );
+    return r;
+}
+
+#endif
+
+#ifdef TEST
+#include <_PDCLIB_test.h>
+
+int main( void )
+{
+    /* Testing covered by fread(). */
+    return TEST_RESULTS;
+}
+
+#endif
+