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 - 2021, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acapps.h"
13 
14 #define _COMPONENT          ACPI_TOOLS
15 ACPI_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  ******************************************************************************/
cm_get_file_size(ACPI_FILE file)29 u32 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 
61 offset_error:
62 	fprintf(stderr, "Could not get file offset\n");
63 	return (ACPI_UINT32_MAX);
64 
65 seek_error:
66 	fprintf(stderr, "Could not set file offset\n");
67 	return (ACPI_UINT32_MAX);
68 }
69