📄 preadwrite.c
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/* Tests for pread and pwrite. Copyright (C) 1998, 2000 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */#define _GNU_SOURCE#include <stdlib.h>#include <stdio.h>#include <search.h>#include <errno.h>#include <error.h>#include <string.h>#include <unistd.h>#define TESTFILE_NAME "CRAP.XXXXXX"#define STRINGIFY(s) STRINGIFY2 (s)#define STRINGIFY2(s) #s/* These are for the temporary file we generate. */char *name;int fd;/* Test the 32-bit versions first. */#define PREAD pread#define PWRITE pwriteint test(int argc, char *argv[]){ char buf[1000]; char res[1000]; int i; memset (buf, '\0', sizeof (buf)); memset (res, '\xff', sizeof (res)); if (write (fd, buf, sizeof (buf)) != sizeof (buf)) error (EXIT_FAILURE, errno, "during write"); for (i = 100; i < 200; ++i) buf[i] = i; if (PWRITE (fd, buf + 100, 100, 100) != 100) error (EXIT_FAILURE, errno, "during %s", STRINGIFY (PWRITE)); for (i = 450; i < 600; ++i) buf[i] = i; if (PWRITE (fd, buf + 450, 150, 450) != 150) error (EXIT_FAILURE, errno, "during %s", STRINGIFY (PWRITE)); if (PREAD (fd, res, sizeof (buf) - 50, 50) != sizeof (buf) - 50) error (EXIT_FAILURE, errno, "during %s", STRINGIFY (PREAD)); close (fd); unlink (name); return memcmp (buf + 50, res, sizeof (buf) - 50);}/* Test the 64-bit versions as well. */#if defined __UCLIBC_HAS_LFS__ #undef PREAD#undef PWRITE#define PREAD pread64#define PWRITE pwrite64int test64(int argc, char *argv[]){ char buf[1000]; char res[1000]; int i; memset (buf, '\0', sizeof (buf)); memset (res, '\xff', sizeof (res)); if (write (fd, buf, sizeof (buf)) != sizeof (buf)) error (EXIT_FAILURE, errno, "during write"); for (i = 100; i < 200; ++i) buf[i] = i; if (PWRITE (fd, buf + 100, 100, 100) != 100) error (EXIT_FAILURE, errno, "during %s", STRINGIFY (PWRITE)); for (i = 450; i < 600; ++i) buf[i] = i; if (PWRITE (fd, buf + 450, 150, 450) != 150) error (EXIT_FAILURE, errno, "during %s", STRINGIFY (PWRITE)); if (PREAD (fd, res, sizeof (buf) - 50, 50) != sizeof (buf) - 50) error (EXIT_FAILURE, errno, "during %s", STRINGIFY (PREAD)); close (fd); unlink (name); return memcmp (buf + 50, res, sizeof (buf) - 50);}#endifvoid prepare(void){ if (!name) { name = malloc (BUFSIZ); if (name == NULL) error (EXIT_FAILURE, errno, "cannot allocate file name"); } strncpy(name, TESTFILE_NAME, BUFSIZ); /* Open our test file. */ fd = mkstemp (name); if (fd == -1) error (EXIT_FAILURE, errno, "cannot open test file `%s'", name);}int main (int argc, char **argv){ int result = 0; prepare(); result+=test(argc, argv); if (result) { fprintf(stderr, "pread/pwrite test failed.\n"); return(EXIT_FAILURE); } fprintf(stderr, "pread/pwrite test successful.\n");#if defined __UCLIBC_HAS_LFS__ prepare(); result+=test64(argc, argv); if (result) { fprintf(stderr, "pread64/pwrite64 test failed.\n"); return(EXIT_FAILURE); } fprintf(stderr, "pread64/pwrite64 test successful.\n");#endif return(EXIT_SUCCESS);}
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