/*
 *
 *   Copyright (c) International Business Machines  Corp., 2001
 *
 *   This program is free software;  you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program 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 General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program;  if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

/*
 * Test Name: mmap01
 *
 * Test Description:
 *  Verify that, mmap() succeeds when used to map a file where size of the
 *  file is not a multiple of the page size, the memory area beyond the end
 *  of the file to the end of the page is accessible. Also, verify that
 *  this area is all zeroed and the modifications done to this area are
 *  not written to the file.
 *
 * Expected Result:
 *  mmap() should succeed returning the address of the mapped region.
 *  The memory area beyond the end of file to the end of page should be
 *  filled with zero.
 *  The changes beyond the end of file should not get written to the file.
 *
 * Algorithm:
 *  Setup:
 *   Setup signal handling.
 *   Pause for SIGUSR1 if option specified.
 *   Create temporary directory.
 *
 *  Test:
 *   Loop if the proper options are given.
 *   Execute system call
 *   Check return code, if system call failed (return=-1)
 *	Log the errno and Issue a FAIL message.
 *   Otherwise,
 *	Verify the Functionality of system call
 *      if successful,
 *		Issue Functionality-Pass message.
 *      Otherwise,
 *		Issue Functionality-Fail message.
 *  Cleanup:
 *   Print timing stats if options given
 *   Delete the temporary directory created.
 *
 * Usage:  <for command-line>
 *  mmap01 [-c n] [-f] [-i n] [-I x] [-P x] [-t]
 *     where,  -c n : Run n copies concurrently.
 *             -f   : Turn off functionality Testing.
 *	       -i n : Execute test n times.
 *	       -I x : Execute test for x seconds.
 *	       -P x : Pause for x seconds between iterations.
 *	       -t   : Turn on syscall timing.
 *
 * HISTORY
 *	07/2001 Ported by Wayne Boyer
 *
 * RESTRICTIONS:
 *  None.
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <signal.h>
#include <stdint.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/shm.h>

#define TEMPFILE	"mmapfile"

char *TCID = "mmap01";		/* Test program identifier.    */
int TST_TOTAL = 1;		/* Total number of test cases. */
extern int Tst_count;		/* Test Case counter for tst_* routines */
char *addr;			/* addr of memory mapped region */
char *dummy;			/* dummy string */
size_t page_sz;			/* system page size */
size_t file_sz;			/* mapped file size */
int fildes;			/* file descriptor for tempfile */
char Cmd_buffer[BUFSIZ];	/* command buffer to hold test command */

void setup();			/* Main setup function of test */
void cleanup();			/* cleanup function for the test */

int main(int ac, char **av)
{
	int lc;			/* loop counter */
	char *msg;		/* message returned from parse_opts */
	int i;
	/* Perform global setup for test */
	struct stat stat_buf;
	char write_buf[] = "ABCD\n EFGH\n"; //41424344 

	/* Creat a temporary file used for mapping */
	if ((fildes = open(TEMPFILE, O_RDWR | O_CREAT, 0666)) < 0) {
		printf( "open() on %s Failed, errno=%d : %s", TEMPFILE, errno, strerror(errno));
		cleanup();
	}

	/* Write some data into temporary file */
	if (write(fildes, write_buf, strlen(write_buf)) != strlen(write_buf)) {
		printf("write() on %s Failed, errno=%d : %s", TEMPFILE, errno, strerror(errno));
		cleanup();
	}

	/* Get the size of temporary file */
	if (stat(TEMPFILE, &stat_buf) < 0) {
		printf( "stat() on %s Failed, errno=%d : %s", TEMPFILE, errno, strerror(errno));
		cleanup();
	}
	file_sz = stat_buf.st_size;

	/* Get the system page size */
	if ((page_sz = getpagesize()) < 0) {
		printf("getpagesize() fails to get system page size");
		cleanup();
	}

	/* Allocate and initialize dummy string of system page size bytes */
	if ((dummy = (char *)calloc(page_sz, sizeof(char))) == NULL) {
		printf("calloc() failed to allocate space");
		cleanup();
	}

	/*
	 * Initialize addr to align with the first segment boundary address
	 * above the break address of the process.
	 */
	addr = (void *)(((intptr_t) sbrk(0) + (SHMLBA - 1)) & ~(SHMLBA - 1));

	printf("dummy 0x%x, addr 0x%x, sbrk 0x%x 0x%x\n", dummy, addr, sbrk, SHMLBA);

	/* Set the break address of the process to the addr plus one
	 * page size.
	 */
	if ((intptr_t) sbrk(SHMLBA + page_sz) == -1) {
		printf("sbrk(SHMLBA + page_sz) failed");
		cleanup();
	}

	/* Initialize one page region from addr with 'A' */
	memset(addr, 'A', page_sz);


#if 0
/* delayed loops */
/* Hera is one loop which read all data which are in addr -> all are 0x41414141 which is correct */
	int *test = (int *)addr;

	/* +1 caused that I read one word after allocated space */ 
	for( i = 0; i<(page_sz/4 + 1); i++) {
		printf("0x%x: 0x%x\n", test, *test);
		test++;
	}


/* test with printf - on nfs works, on initramfs sometimes failed */
	printf("hello\n");

/* test with syscall */
	sync();
#endif

		/*
		 * Call mmap to map the temporary file beyond EOF
		 * with write access.
		 */
		errno = 0;
		addr = mmap(addr, page_sz, PROT_READ | PROT_WRITE,
			    MAP_FILE | MAP_SHARED | MAP_FIXED, fildes, 0);

		/* Check for the return value of mmap() */
		if (addr == MAP_FAILED) {
			printf("mmap() Failed on %s, errno=%d : %s",
				 TEMPFILE, errno, strerror(errno));
		}


	printf("file size=0x%x, first writing addr=0x%x\n", file_sz, &addr[file_sz]);

/* 1. checking loop after mmap */
/* read fist 15 words mmap memory */
	int *file = (int *)addr;
	for( i = 0; i<(15); i++) {
		printf("0x%x: 0x%08x\n", file, *file);
		file++;
	}

	/*
	 * Initialize memory beyond file size
	 */
	addr[file_sz] = 0x11;
	addr[file_sz + 1] = 0x12;
	addr[file_sz + 2] = 0x13;

/* 2. checking after writing - always is correct */
	printf("------------\n");
	file = (int *)addr;
	for( i = 0; i<(15); i++) {
		printf("0x%x: 0x%08x\n", file, *file);
		file++;
	}

	/*
	 * Synchronize the mapped memory region
	 * with the file.
	 */
	if (msync(addr, page_sz, MS_SYNC) != 0) {
		printf("msync() failed to "
				"synchronize mapped file, error:%d",
				errno);
		cleanup();
	}

	/* Create the command which will be executed in the test */
	sprintf(Cmd_buffer, "grep XYZ %s > /dev/null", TEMPFILE);


	/*
		* Now, Search for the pattern 'XYZ' in the
		* temporary file.  The pattern should not be
		* found and the return value should be 1.
		*/
	if (system(Cmd_buffer) != 0) {
		printf("Functionality of mmap() successful");
	} else {
		printf("Specified pattern found in file");
	}




		/* Clean up things in case we are looping */
		/* Unmap the mapped memory */
		if (munmap(addr, page_sz) != 0) {
			printf("munmap() fails to unmap the "
				 "memory, errno=%d", errno);
		}




	/* Call cleanup() to undo setup done for the test. */
	cleanup();
	 /*NOTREACHED*/ return 0;
}				/* End main */

/*
 * cleanup() - performs all ONE TIME cleanup for this test at
 *             completion or premature exit.
 *	       Free the memory allocated to  variable.
 *	       Remove the temporary directory created.
 */
void cleanup()
{
	/*
	 * print timing stats if that option was specified.
	 */
	close(fildes);

	/* Free the memory allocated for dummy string */
	if (dummy) {
		free(dummy);
	}
}