-// ----------------------------------------------------------------------------
-// $Id$
-// ----------------------------------------------------------------------------
-// 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 */ };
+/* 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
+