xref: /linux/tools/power/acpi/common/cmfsize.c (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
1 /******************************************************************************
2  *
3  * Module Name: cfsize - Common get file size function
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2015, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acapps.h"
47 #include <stdio.h>
48 
49 #define _COMPONENT          ACPI_TOOLS
50 ACPI_MODULE_NAME("cmfsize")
51 
52 /*******************************************************************************
53  *
54  * FUNCTION:    cm_get_file_size
55  *
56  * PARAMETERS:  file                    - Open file descriptor
57  *
58  * RETURN:      File Size. On error, -1 (ACPI_UINT32_MAX)
59  *
60  * DESCRIPTION: Get the size of a file. Uses seek-to-EOF. File must be open.
61  *              Does not disturb the current file pointer.
62  *
63  ******************************************************************************/
64 u32 cm_get_file_size(ACPI_FILE file)
65 {
66 	long file_size;
67 	long current_offset;
68 	acpi_status status;
69 
70 	/* Save the current file pointer, seek to EOF to obtain file size */
71 
72 	current_offset = acpi_os_get_file_offset(file);
73 	if (current_offset < 0) {
74 		goto offset_error;
75 	}
76 
77 	status = acpi_os_set_file_offset(file, 0, ACPI_FILE_END);
78 	if (ACPI_FAILURE(status)) {
79 		goto seek_error;
80 	}
81 
82 	file_size = acpi_os_get_file_offset(file);
83 	if (file_size < 0) {
84 		goto offset_error;
85 	}
86 
87 	/* Restore original file pointer */
88 
89 	status = acpi_os_set_file_offset(file, current_offset, ACPI_FILE_BEGIN);
90 	if (ACPI_FAILURE(status)) {
91 		goto seek_error;
92 	}
93 
94 	return ((u32)file_size);
95 
96 offset_error:
97 	acpi_log_error("Could not get file offset");
98 	return (ACPI_UINT32_MAX);
99 
100 seek_error:
101 	acpi_log_error("Could not set file offset");
102 	return (ACPI_UINT32_MAX);
103 }
104