xref: /OK3568_Linux_fs/kernel/tools/power/acpi/common/cmfsize.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2*4882a593Smuzhiyun /******************************************************************************
3*4882a593Smuzhiyun  *
4*4882a593Smuzhiyun  * Module Name: cfsize - Common get file size function
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * Copyright (C) 2000 - 2020, Intel Corp.
7*4882a593Smuzhiyun  *
8*4882a593Smuzhiyun  *****************************************************************************/
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun #include <acpi/acpi.h>
11*4882a593Smuzhiyun #include "accommon.h"
12*4882a593Smuzhiyun #include "acapps.h"
13*4882a593Smuzhiyun 
14*4882a593Smuzhiyun #define _COMPONENT          ACPI_TOOLS
15*4882a593Smuzhiyun ACPI_MODULE_NAME("cmfsize")
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun /*******************************************************************************
18*4882a593Smuzhiyun  *
19*4882a593Smuzhiyun  * FUNCTION:    cm_get_file_size
20*4882a593Smuzhiyun  *
21*4882a593Smuzhiyun  * PARAMETERS:  file                    - Open file descriptor
22*4882a593Smuzhiyun  *
23*4882a593Smuzhiyun  * RETURN:      File Size. On error, -1 (ACPI_UINT32_MAX)
24*4882a593Smuzhiyun  *
25*4882a593Smuzhiyun  * DESCRIPTION: Get the size of a file. Uses seek-to-EOF. File must be open.
26*4882a593Smuzhiyun  *              Does not disturb the current file pointer.
27*4882a593Smuzhiyun  *
28*4882a593Smuzhiyun  ******************************************************************************/
cm_get_file_size(ACPI_FILE file)29*4882a593Smuzhiyun u32 cm_get_file_size(ACPI_FILE file)
30*4882a593Smuzhiyun {
31*4882a593Smuzhiyun 	long file_size;
32*4882a593Smuzhiyun 	long current_offset;
33*4882a593Smuzhiyun 	acpi_status status;
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun 	/* Save the current file pointer, seek to EOF to obtain file size */
36*4882a593Smuzhiyun 
37*4882a593Smuzhiyun 	current_offset = ftell(file);
38*4882a593Smuzhiyun 	if (current_offset < 0) {
39*4882a593Smuzhiyun 		goto offset_error;
40*4882a593Smuzhiyun 	}
41*4882a593Smuzhiyun 
42*4882a593Smuzhiyun 	status = fseek(file, 0, SEEK_END);
43*4882a593Smuzhiyun 	if (ACPI_FAILURE(status)) {
44*4882a593Smuzhiyun 		goto seek_error;
45*4882a593Smuzhiyun 	}
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun 	file_size = ftell(file);
48*4882a593Smuzhiyun 	if (file_size < 0) {
49*4882a593Smuzhiyun 		goto offset_error;
50*4882a593Smuzhiyun 	}
51*4882a593Smuzhiyun 
52*4882a593Smuzhiyun 	/* Restore original file pointer */
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun 	status = fseek(file, current_offset, SEEK_SET);
55*4882a593Smuzhiyun 	if (ACPI_FAILURE(status)) {
56*4882a593Smuzhiyun 		goto seek_error;
57*4882a593Smuzhiyun 	}
58*4882a593Smuzhiyun 
59*4882a593Smuzhiyun 	return ((u32)file_size);
60*4882a593Smuzhiyun 
61*4882a593Smuzhiyun offset_error:
62*4882a593Smuzhiyun 	fprintf(stderr, "Could not get file offset\n");
63*4882a593Smuzhiyun 	return (ACPI_UINT32_MAX);
64*4882a593Smuzhiyun 
65*4882a593Smuzhiyun seek_error:
66*4882a593Smuzhiyun 	fprintf(stderr, "Could not set file offset\n");
67*4882a593Smuzhiyun 	return (ACPI_UINT32_MAX);
68*4882a593Smuzhiyun }
69