X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=functions%2Fstdio%2Ffread.c;h=d1afc99be3016a720a7d2311e45f8315eaeaeaad;hb=b1fc26afebd4d557ff89a44bc21767a8704c3809;hp=905ff4dc906c674f2d5ab776569e772066c5a258;hpb=34893ecc2200dc7017c36a54cb6c5f4c2378b5ec;p=pdclib

diff --git a/functions/stdio/fread.c b/functions/stdio/fread.c
index 905ff4d..d1afc99 100644
--- a/functions/stdio/fread.c
+++ b/functions/stdio/fread.c
@@ -1,8 +1,82 @@
-// ----------------------------------------------------------------------------
-// $Id$
-// ----------------------------------------------------------------------------
-// Public Domain C Library - http://pdclib.sourceforge.net
-// This code is Public Domain. Use, modify, and redistribute at will.
-// ----------------------------------------------------------------------------
-
-size_t fread( void * restrict ptr, size_t size, size_t nelem, FILE * restrict stream ) { /* TODO */ };
+/* fwrite( 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_glue.h>
+
+#include <stdbool.h>
+#include <string.h>
+
+size_t fread( void * _PDCLIB_restrict ptr, size_t size, size_t nmemb, struct _PDCLIB_file_t * _PDCLIB_restrict stream )
+{
+    if ( _PDCLIB_prepread( stream ) == EOF )
+    {
+        return 0;
+    }
+    char * dest = (char *)ptr;
+    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->bufidx == stream->bufend )
+            {
+                if ( _PDCLIB_fillbuffer( stream ) == EOF )
+                {
+                    /* Could not read requested data */
+                    return nmemb_i;
+                }
+            }
+            dest[ nmemb_i * size + size_i ] = stream->buffer[ stream->bufidx++ ];
+        }
+    }
+    return nmemb_i;
+}
+
+#endif
+
+#ifdef TEST
+#include <_PDCLIB_test.h>
+
+int main( void )
+{
+    FILE * fh;
+    char const * message = "Testing fwrite()...\n";
+    char buffer[21];
+    buffer[20] = 'x';
+    TESTCASE( ( fh = tmpfile() ) != NULL );
+    /* fwrite() / readback */
+    TESTCASE( fwrite( message, 1, 20, fh ) == 20 );
+    rewind( fh );
+    TESTCASE( fread( buffer, 1, 20, fh ) == 20 );
+    TESTCASE( memcmp( buffer, message, 20 ) == 0 );
+    TESTCASE( buffer[20] == 'x' );
+    /* same, different nmemb / size settings */
+    rewind( fh );
+    TESTCASE( memset( buffer, '\0', 20 ) == buffer );
+    TESTCASE( fwrite( message, 5, 4, fh ) == 4 );
+    rewind( fh );
+    TESTCASE( fread( buffer, 5, 4, fh ) == 4 );
+    TESTCASE( memcmp( buffer, message, 20 ) == 0 );
+    TESTCASE( buffer[20] == 'x' );
+    /* same... */
+    rewind( fh );
+    TESTCASE( memset( buffer, '\0', 20 ) == buffer );
+    TESTCASE( fwrite( message, 20, 1, fh ) == 1 );
+    rewind( fh );
+    TESTCASE( fread( buffer, 20, 1, fh ) == 1 );
+    TESTCASE( memcmp( buffer, message, 20 ) == 0 );
+    TESTCASE( buffer[20] == 'x' );
+    /* Done. */
+    TESTCASE( fclose( fh ) == 0 );
+    return TEST_RESULTS;
+}
+
+#endif
+