]> pd.if.org Git - pdclib.old/blobdiff - functions/stdio/fwrite.c
Namespace cleanliness: Rename all ***_unlocked functions to _PDCLIB_***_unlocked.
[pdclib.old] / functions / stdio / fwrite.c
index 4eece021380b9a43ed0925fa3a9f2c6784e1cca9..c9396bf6751fcf6df33fd3f0e73095f2a8b8ae5f 100644 (file)
@@ -1,8 +1,115 @@
-// ----------------------------------------------------------------------------
-// $Id$
-// ----------------------------------------------------------------------------
-// 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>
+
+//TODO OS(2012-08-01): Ascertain purpose of lineend & potentially remove
+
+size_t _PDCLIB_fwrite_unlocked( const void * _PDCLIB_restrict ptr, 
+               size_t size, size_t nmemb, 
+               FILE * _PDCLIB_restrict stream )
+{
+    if ( _PDCLIB_prepwrite( stream ) == EOF )
+    {
+        return 0;
+    }
+    _PDCLIB_size_t offset = 0;
+    //bool lineend = false;
+    size_t nmemb_i;
+    for ( nmemb_i = 0; nmemb_i < nmemb; ++nmemb_i )
+    {
+        for ( size_t size_i = 0; size_i < size; ++size_i )
+        {
+            if ( ( stream->buffer[ stream->bufidx++ ] = ((char*)ptr)[ nmemb_i * size + size_i ] ) == '\n' )
+            {
+                /* Remember last newline, in case we have to do a partial line-buffered flush */
+                offset = stream->bufidx;
+                //lineend = true;
+            }
+            if ( stream->bufidx == stream->bufsize )
+            {
+                if ( _PDCLIB_flushbuffer( stream ) == EOF )
+                {
+                    /* Returning number of objects completely buffered */
+                    return nmemb_i;
+                }
+                //lineend = false;
+                /*
+                 * The entire buffer has been flushed; this means we have to
+                 * reset our newline position as we have already written
+                 * that part of the stream.
+                 */
+                offset = 0;
+            }
+        }
+    }
+    /* Fully-buffered streams are OK. Non-buffered streams must be flushed,
+       line-buffered streams only if there's a newline in the buffer.
+    */
+    switch ( stream->status & ( _IONBF | _IOLBF ) )
+    {
+        case _IONBF:
+            if ( _PDCLIB_flushbuffer( stream ) == EOF )
+            {
+                /* We are in a pinch here. We have an error, which requires a
+                   return value < nmemb. On the other hand, all objects have
+                   been written to buffer, which means all the caller had to
+                   do was removing the error cause, and re-flush the stream...
+                   Catch 22. We'll return a value one short, to indicate the
+                   error, and can't really do anything about the inconsistency.
+                */
+                return nmemb_i - 1;
+            }
+            break;
+        case _IOLBF:
+            {
+            size_t bufidx = stream->bufidx;
+            stream->bufidx = offset;
+            if ( _PDCLIB_flushbuffer( stream ) == EOF )
+            {
+                /* See comment above. */
+                stream->bufidx = bufidx;
+                return nmemb_i - 1;
+            }
+            stream->bufidx = bufidx - offset;
+            memmove( stream->buffer, stream->buffer + offset, stream->bufidx );
+            }
+    }
+    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
+