/*

 * Copyright (c) 2015-2017, Intel Corporation

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 *

 *  * Redistributions of source code must retain the above copyright notice,

 *    this list of conditions and the following disclaimer.

 *  * Redistributions in binary form must reproduce the above copyright notice,

 *    this list of conditions and the following disclaimer in the documentation

 *    and/or other materials provided with the distribution.

 *  * Neither the name of Intel Corporation nor the names of its contributors

 *    may be used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE

 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

 * POSSIBILITY OF SUCH DAMAGE.

 */

#include "pt_section.h"

#include "pt_section_file.h"

#include "intel-pt.h"

#include <stdlib.h>

#include <stdio.h>

/* This is a variation of ptunit-section.c.

 *

 * We provide pt_section_map() et.al. that are normally provided by mmap-based

 * section implementations.  Our implementation falls back to file-based

 * sections so we're able to test them.

 *

 * The actual test is in ptunit-section.c.

 */

/* The file status used for detecting changes to a file between unmap and map.

 *

 * In our case, the changes always affect the size of the file.

 */

struct pt_file_status {

	/* The size in bytes. */

	long size;

};

int pt_section_mk_status(void **pstatus, uint64_t *psize, const char *filename)

{

	struct pt_file_status *status;

	FILE *file;

	long size;

	int errcode;

	if (!pstatus || !psize)

		return -pte_internal;

	file = fopen(filename, "rb");

	if (!file)

		return -pte_bad_image;

	errcode = fseek(file, 0, SEEK_END);

	if (errcode) {

		errcode = -pte_bad_image;

		goto out_file;

	}

	size = ftell(file);

	if (size < 0) {

		errcode = -pte_bad_image;

		goto out_file;

	}

	status = malloc(sizeof(*status));

	if (!status) {

		errcode = -pte_nomem;

		goto out_file;

	}

	status->size = size;

	*pstatus = status;

	*psize = (uint64_t) size;

	errcode = 0;

out_file:

	fclose(file);

	return errcode;

}

int pt_section_map(struct pt_section *section)

{

	struct pt_file_status *status;

	const char *filename;

	uint16_t mcount;

	FILE *file;

	long size;

	int errcode;

	if (!section)

		return -pte_internal;

	errcode = pt_section_lock(section);

	if (errcode < 0)

		return errcode;

	mcount = section->mcount + 1;

	if (mcount > 1) {

		section->mcount = mcount;

		return pt_section_unlock(section);

	}

	errcode = -pte_internal;

	if (!mcount)

		goto out_unlock;

	if (section->mapping)

		goto out_unlock;

	filename = section->filename;

	if (!filename)

		goto out_unlock;

	status = section->status;

	if (!status)

		goto out_unlock;

	errcode = -pte_bad_image;

	file = fopen(filename, "rb");

	if (!file)

		goto out_unlock;

	errcode = fseek(file, 0, SEEK_END);

	if (errcode) {

		errcode = -pte_bad_image;

		goto out_file;

	}

	errcode = -pte_bad_image;

	size = ftell(file);

	if (size < 0)

		goto out_file;

	if (size != status->size)

		goto out_file;

	/* We need to keep the file open on success.  It will be closed when

	 * the section is unmapped.

	 */

	errcode = pt_sec_file_map(section, file);

	if (!errcode) {

		section->mcount = 1;

		return pt_section_unlock(section);

	}

out_file:

	fclose(file);

out_unlock:

	(void) pt_section_unlock(section);

	return errcode;

}