xref: /linux/tools/power/acpi/common/cmfsize.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /******************************************************************************
2  *
3  * Module Name: cfsize - Common get file size function
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2017, 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 
48 #define _COMPONENT          ACPI_TOOLS
49 ACPI_MODULE_NAME("cmfsize")
50 
51 /*******************************************************************************
52  *
53  * FUNCTION:    cm_get_file_size
54  *
55  * PARAMETERS:  file                    - Open file descriptor
56  *
57  * RETURN:      File Size. On error, -1 (ACPI_UINT32_MAX)
58  *
59  * DESCRIPTION: Get the size of a file. Uses seek-to-EOF. File must be open.
60  *              Does not disturb the current file pointer.
61  *
62  ******************************************************************************/
63 u32 cm_get_file_size(ACPI_FILE file)
64 {
65 	long file_size;
66 	long current_offset;
67 	acpi_status status;
68 
69 	/* Save the current file pointer, seek to EOF to obtain file size */
70 
71 	current_offset = ftell(file);
72 	if (current_offset < 0) {
73 		goto offset_error;
74 	}
75 
76 	status = fseek(file, 0, SEEK_END);
77 	if (ACPI_FAILURE(status)) {
78 		goto seek_error;
79 	}
80 
81 	file_size = ftell(file);
82 	if (file_size < 0) {
83 		goto offset_error;
84 	}
85 
86 	/* Restore original file pointer */
87 
88 	status = fseek(file, current_offset, SEEK_SET);
89 	if (ACPI_FAILURE(status)) {
90 		goto seek_error;
91 	}
92 
93 	return ((u32)file_size);
94 
95 offset_error:
96 	fprintf(stderr, "Could not get file offset\n");
97 	return (ACPI_UINT32_MAX);
98 
99 seek_error:
100 	fprintf(stderr, "Could not set file offset\n");
101 	return (ACPI_UINT32_MAX);
102 }
103