diff options
author | tcsullivan <tullivan99@gmail.com> | 2018-11-17 13:02:57 -0500 |
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committer | tcsullivan <tullivan99@gmail.com> | 2018-11-17 13:02:57 -0500 |
commit | c6ef89664b8c0d7aa85bddd5c7014aa6df82cbe7 (patch) | |
tree | d1f9d09412a46bdf4344fe30392455070a72993d /src/pdclib/functions/stdio/setvbuf.c | |
parent | db38c4b9dac461de0ed75bf6d079dacba1b31bc9 (diff) |
added pdclib, removed sash
Diffstat (limited to 'src/pdclib/functions/stdio/setvbuf.c')
-rw-r--r-- | src/pdclib/functions/stdio/setvbuf.c | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/src/pdclib/functions/stdio/setvbuf.c b/src/pdclib/functions/stdio/setvbuf.c new file mode 100644 index 0000000..00592ff --- /dev/null +++ b/src/pdclib/functions/stdio/setvbuf.c @@ -0,0 +1,108 @@ +/* setvbuf( FILE *, char *, int, size_t ) + + 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> +#include <stdlib.h> +#include <limits.h> + +#ifndef REGTEST + +int setvbuf( struct _PDCLIB_file_t * _PDCLIB_restrict stream, char * _PDCLIB_restrict buf, int mode, size_t size ) +{ + switch ( mode ) + { + case _IONBF: + /* When unbuffered I/O is requested, we keep the buffer anyway, as + we don't want to e.g. flush the stream for every character of a + stream being printed. + */ + break; + case _IOFBF: + case _IOLBF: + if ( size > INT_MAX || size == 0 ) + { + /* PDCLib only supports buffers up to INT_MAX in size. A size + of zero doesn't make sense. + */ + return -1; + } + if ( buf == NULL ) + { + /* User requested buffer size, but leaves it to library to + allocate the buffer. + */ + /* If current buffer is big enough for requested size, but not + over twice as big (and wasting memory space), we use the + current buffer (i.e., do nothing), to save the malloc() / + free() overhead. + */ + if ( ( stream->bufsize < size ) || ( stream->bufsize > ( size << 1 ) ) ) + { + /* Buffer too small, or much too large - allocate. */ + if ( ( buf = (char *) malloc( size ) ) == NULL ) + { + /* Out of memory error. */ + return -1; + } + /* This buffer must be free()d on fclose() */ + stream->status |= _PDCLIB_FREEBUFFER; + } + } + stream->buffer = buf; + stream->bufsize = size; + break; + default: + /* If mode is something else than _IOFBF, _IOLBF or _IONBF -> exit */ + return -1; + } + /* Deleting current buffer mode */ + stream->status &= ~( _IOFBF | _IOLBF | _IONBF ); + /* Set user-defined mode */ + stream->status |= mode; + return 0; +} + +#endif + +#ifdef TEST + +#include "_PDCLIB_test.h" + +#include <errno.h> + +#define BUFFERSIZE 500 + +int main( void ) +{ +#ifndef REGTEST + char buffer[ BUFFERSIZE ]; + FILE * fh; + /* full buffered, user-supplied buffer */ + TESTCASE( ( fh = tmpfile() ) != NULL ); + TESTCASE( setvbuf( fh, buffer, _IOFBF, BUFFERSIZE ) == 0 ); + TESTCASE( fh->buffer == buffer ); + TESTCASE( fh->bufsize == BUFFERSIZE ); + TESTCASE( ( fh->status & ( _IOFBF | _IONBF | _IOLBF ) ) == _IOFBF ); + TESTCASE( fclose( fh ) == 0 ); + /* line buffered, lib-supplied buffer */ + TESTCASE( ( fh = tmpfile() ) != NULL ); + TESTCASE( setvbuf( fh, NULL, _IOLBF, BUFFERSIZE ) == 0 ); + TESTCASE( fh->buffer != NULL ); + TESTCASE( fh->bufsize == BUFFERSIZE ); + TESTCASE( ( fh->status & ( _IOFBF | _IONBF | _IOLBF ) ) == _IOLBF ); + TESTCASE( fclose( fh ) == 0 ); + /* not buffered, user-supplied buffer */ + TESTCASE( ( fh = tmpfile() ) != NULL ); + TESTCASE( setvbuf( fh, buffer, _IONBF, BUFFERSIZE ) == 0 ); + TESTCASE( ( fh->status & ( _IOFBF | _IONBF | _IOLBF ) ) == _IONBF ); + TESTCASE( fclose( fh ) == 0 ); +#else + puts( " NOTEST setvbuf() test driver is PDCLib-specific." ); +#endif + return TEST_RESULTS; +} + +#endif |