1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/******************************************************************************
3 *
4 * Module Name: cmfsize - Common get file size function
5 *
6 * Copyright (C) 2000 - 2023, Intel Corp.
7 *
8 *****************************************************************************/
9
10#include <acpi/acpi.h>
11#include "accommon.h"
12#include "acapps.h"
13
14#define _COMPONENT ACPI_TOOLS
15ACPI_MODULE_NAME("cmfsize")
16
17/*******************************************************************************
18 *
19 * FUNCTION: cm_get_file_size
20 *
21 * PARAMETERS: file - Open file descriptor
22 *
23 * RETURN: File Size. On error, -1 (ACPI_UINT32_MAX)
24 *
25 * DESCRIPTION: Get the size of a file. Uses seek-to-EOF. File must be open.
26 * Does not disturb the current file pointer.
27 *
28 ******************************************************************************/
29u32 cm_get_file_size(ACPI_FILE file)
30{
31 long file_size;
32 long current_offset;
33 acpi_status status;
34
35 /* Save the current file pointer, seek to EOF to obtain file size */
36
37 current_offset = ftell(file);
38 if (current_offset < 0) {
39 goto offset_error;
40 }
41
42 status = fseek(file, 0, SEEK_END);
43 if (ACPI_FAILURE(status)) {
44 goto seek_error;
45 }
46
47 file_size = ftell(file);
48 if (file_size < 0) {
49 goto offset_error;
50 }
51
52 /* Restore original file pointer */
53
54 status = fseek(file, current_offset, SEEK_SET);
55 if (ACPI_FAILURE(status)) {
56 goto seek_error;
57 }
58
59 return ((u32)file_size);
60
61offset_error:
62 fprintf(stderr, "Could not get file offset\n");
63 return (ACPI_UINT32_MAX);
64
65seek_error:
66 fprintf(stderr, "Could not set file offset\n");
67 return (ACPI_UINT32_MAX);
68}
69

source code of linux/tools/power/acpi/common/cmfsize.c