BizHawk/waterbox/libc/functions/stdio/fread.c

88 lines
2.2 KiB
C

/* 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_io.h"
#include <stdbool.h>
#include <string.h>
size_t _PDCLIB_fread_unlocked(
void * _PDCLIB_restrict ptr,
size_t size, size_t nmemb,
FILE * _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 )
{
size_t numread = _PDCLIB_getchars( &dest[ nmemb_i * size ], size, EOF,
stream );
if( numread != size )
break;
}
return nmemb_i;
}
size_t fread( void * _PDCLIB_restrict ptr,
size_t size, size_t nmemb,
FILE * _PDCLIB_restrict stream )
{
_PDCLIB_flockfile( stream );
size_t r = _PDCLIB_fread_unlocked( ptr, size, nmemb, stream );
_PDCLIB_funlockfile( stream );
return r;
}
#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