diff options
author | tcsullivan <tullivan99@gmail.com> | 2018-11-17 13:02:57 -0500 |
---|---|---|
committer | tcsullivan <tullivan99@gmail.com> | 2018-11-17 13:02:57 -0500 |
commit | c6ef89664b8c0d7aa85bddd5c7014aa6df82cbe7 (patch) | |
tree | d1f9d09412a46bdf4344fe30392455070a72993d /src/pdclib/platform/example/functions/stdio/tmpfile.c | |
parent | db38c4b9dac461de0ed75bf6d079dacba1b31bc9 (diff) |
added pdclib, removed sash
Diffstat (limited to 'src/pdclib/platform/example/functions/stdio/tmpfile.c')
-rw-r--r-- | src/pdclib/platform/example/functions/stdio/tmpfile.c | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/src/pdclib/platform/example/functions/stdio/tmpfile.c b/src/pdclib/platform/example/functions/stdio/tmpfile.c new file mode 100644 index 0000000..585a61d --- /dev/null +++ b/src/pdclib/platform/example/functions/stdio/tmpfile.c @@ -0,0 +1,114 @@ +/* tmpfile( void ) + + 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/_PDCLIB_glue.h" + +#include <inttypes.h> +#include <stdlib.h> +#include <string.h> + +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> + +extern struct _PDCLIB_file_t * _PDCLIB_filelist; + +/* This is an example implementation of tmpfile() fit for use with POSIX + kernels. +*/ +struct _PDCLIB_file_t * tmpfile( void ) +{ + FILE * rc; + /* This is the chosen way to get high-quality randomness. Replace as + appropriate. + */ + FILE * randomsource = fopen( "/proc/sys/kernel/random/uuid", "rb" ); + char filename[ L_tmpnam ]; + _PDCLIB_fd_t fd; + if ( randomsource == NULL ) + { + return NULL; + } + for ( ;; ) + { + /* Get a filename candidate. What constitutes a valid filename and + where temporary files are usually located is platform-dependent, + which is one reason why this function is located in the platform + overlay. The other reason is that a *good* implementation should + use high-quality randomness instead of a pseudo-random sequence to + generate the filename candidate, which is *also* platform-dependent. + */ + unsigned int random; + fscanf( randomsource, "%u", &random ); + sprintf( filename, "/tmp/%u.tmp", random ); + /* Check if file of this name exists. Note that fopen() is a very weak + check, which does not take e.g. access permissions into account + (file might exist but not readable). Replace with something more + appropriate. + */ + fd = open( filename, O_CREAT | O_EXCL | O_RDWR, S_IRUSR | S_IWUSR ); + if ( fd != -1 ) + { + break; + } + close( fd ); + } + fclose( randomsource ); + /* See fopen(). */ + if ( ( rc = calloc( 1, sizeof( struct _PDCLIB_file_t ) + _PDCLIB_UNGETCBUFSIZE + L_tmpnam + BUFSIZ ) ) == NULL ) + { + /* No memory to set up FILE structure */ + close( fd ); + return NULL; + } + rc->status = _PDCLIB_filemode( "wb+" ) | _IOLBF | _PDCLIB_DELONCLOSE; + rc->handle = fd; + rc->ungetbuf = (unsigned char *)rc + sizeof( struct _PDCLIB_file_t ); + rc->filename = (char *)rc->ungetbuf + _PDCLIB_UNGETCBUFSIZE; + rc->buffer = rc->filename + L_tmpnam; + strcpy( rc->filename, filename ); + rc->bufsize = BUFSIZ; + rc->bufidx = 0; + rc->ungetidx = 0; + rc->next = _PDCLIB_filelist; + _PDCLIB_filelist = rc; + return rc; +} + +#endif + +#ifdef TEST + +#include "_PDCLIB_test.h" + +#include <string.h> + +int main( void ) +{ + FILE * fh; +#ifndef REGTEST + char filename[ L_tmpnam ]; + FILE * fhtest; +#endif + TESTCASE( ( fh = tmpfile() ) != NULL ); + TESTCASE( fputc( 'x', fh ) == 'x' ); + /* Checking that file is actually there */ + TESTCASE_NOREG( strcpy( filename, fh->filename ) == filename ); + TESTCASE_NOREG( ( fhtest = fopen( filename, "r" ) ) != NULL ); + TESTCASE_NOREG( fclose( fhtest ) == 0 ); + /* Closing tmpfile */ + TESTCASE( fclose( fh ) == 0 ); + /* Checking that file was deleted */ + TESTCASE_NOREG( fopen( filename, "r" ) == NULL ); + return TEST_RESULTS; +} + +#endif |