1 /* Copyright (C) 2010 - 2013 UNISYS CORPORATION
2 * All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or (at
7 * your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
12 * NON INFRINGEMENT. See the GNU General Public License for more
13 * details.
14 */
15
16 #ifndef __VBUSDEVICEINFO_H__
17 #define __VBUSDEVICEINFO_H__
18
19 #include <linux/types.h>
20
21 #pragma pack(push, 1) /* both GCC and VC now allow this pragma */
22
23 /* An array of this struct is present in the channel area for each vbus.
24 * (See vbuschannel.h.)
25 * It is filled in by the client side to provide info about the device
26 * and driver from the client's perspective.
27 */
28 struct ultra_vbus_deviceinfo {
29 u8 devtype[16]; /* short string identifying the device type */
30 u8 drvname[16]; /* driver .sys file name */
31 u8 infostrs[96]; /* sequence of tab-delimited id strings: */
32 /* <DRIVER_REV> <DRIVER_VERTAG> <DRIVER_COMPILETIME> */
33 u8 reserved[128]; /* pad size to 256 bytes */
34 };
35
36 #pragma pack(pop)
37
38 /* Reads chars from the buffer at <src> for <srcmax> bytes, and writes to
39 * the buffer at <p>, which is <remain> bytes long, ensuring never to
40 * overflow the buffer at <p>, using the following rules:
41 * - printable characters are simply copied from the buffer at <src> to the
42 * buffer at <p>
43 * - intervening streaks of non-printable characters in the buffer at <src>
44 * are replaced with a single space in the buffer at <p>
45 * Note that we pay no attention to '\0'-termination.
46 * Returns the number of bytes written to <p>.
47 *
48 * Pass <p> == NULL and <remain> == 0 for this special behavior. In this
49 * case, we simply return the number of bytes that WOULD HAVE been written
50 * to a buffer at <p>, had it been infinitely big.
51 */
52 static inline int
vbuschannel_sanitize_buffer(char * p,int remain,char * src,int srcmax)53 vbuschannel_sanitize_buffer(char *p, int remain, char *src, int srcmax)
54 {
55 int chars = 0;
56 int nonprintable_streak = 0;
57
58 while (srcmax > 0) {
59 if ((*src >= ' ') && (*src < 0x7f)) {
60 if (nonprintable_streak) {
61 if (remain > 0) {
62 *p = ' ';
63 p++;
64 remain--;
65 chars++;
66 } else if (p == NULL) {
67 chars++;
68 }
69 nonprintable_streak = 0;
70 }
71 if (remain > 0) {
72 *p = *src;
73 p++;
74 remain--;
75 chars++;
76 } else if (p == NULL) {
77 chars++;
78 }
79 } else {
80 nonprintable_streak = 1;
81 }
82 src++;
83 srcmax--;
84 }
85 return chars;
86 }
87
88 #define VBUSCHANNEL_ADDACHAR(ch, p, remain, chars) \
89 do { \
90 if (remain <= 0) \
91 break; \
92 *p = ch; \
93 p++; chars++; remain--; \
94 } while (0)
95
96 /* Converts the non-negative value at <num> to an ascii decimal string
97 * at <p>, writing at most <remain> bytes. Note there is NO '\0' termination
98 * written to <p>.
99 *
100 * Returns the number of bytes written to <p>.
101 *
102 * Note that we create this function because we need to do this operation in
103 * an environment-independent way (since we are in a common header file).
104 */
105 static inline int
vbuschannel_itoa(char * p,int remain,int num)106 vbuschannel_itoa(char *p, int remain, int num)
107 {
108 int digits = 0;
109 char s[32];
110 int i;
111
112 if (num == 0) {
113 /* '0' is a special case */
114 if (remain <= 0)
115 return 0;
116 *p = '0';
117 return 1;
118 }
119 /* form a backwards decimal ascii string in <s> */
120 while (num > 0) {
121 if (digits >= (int)sizeof(s))
122 return 0;
123 s[digits++] = (num % 10) + '0';
124 num = num / 10;
125 }
126 if (remain < digits) {
127 /* not enough room left at <p> to hold number, so fill with
128 * '?' */
129 for (i = 0; i < remain; i++, p++)
130 *p = '?';
131 return remain;
132 }
133 /* plug in the decimal ascii string representing the number, by */
134 /* reversing the string we just built in <s> */
135 i = digits;
136 while (i > 0) {
137 i--;
138 *p = s[i];
139 p++;
140 }
141 return digits;
142 }
143
144 /* Reads <devInfo>, and converts its contents to a printable string at <p>,
145 * writing at most <remain> bytes. Note there is NO '\0' termination
146 * written to <p>.
147 *
148 * Pass <devix> >= 0 if you want a device index presented.
149 *
150 * Returns the number of bytes written to <p>.
151 */
152 static inline int
vbuschannel_devinfo_to_string(struct ultra_vbus_deviceinfo * devinfo,char * p,int remain,int devix)153 vbuschannel_devinfo_to_string(struct ultra_vbus_deviceinfo *devinfo,
154 char *p, int remain, int devix)
155 {
156 char *psrc;
157 int nsrc, x, i, pad;
158 int chars = 0;
159
160 psrc = &devinfo->devtype[0];
161 nsrc = sizeof(devinfo->devtype);
162 if (vbuschannel_sanitize_buffer(NULL, 0, psrc, nsrc) <= 0)
163 return 0;
164
165 /* emit device index */
166 if (devix >= 0) {
167 VBUSCHANNEL_ADDACHAR('[', p, remain, chars);
168 x = vbuschannel_itoa(p, remain, devix);
169 p += x;
170 remain -= x;
171 chars += x;
172 VBUSCHANNEL_ADDACHAR(']', p, remain, chars);
173 } else {
174 VBUSCHANNEL_ADDACHAR(' ', p, remain, chars);
175 VBUSCHANNEL_ADDACHAR(' ', p, remain, chars);
176 VBUSCHANNEL_ADDACHAR(' ', p, remain, chars);
177 }
178
179 /* emit device type */
180 x = vbuschannel_sanitize_buffer(p, remain, psrc, nsrc);
181 p += x;
182 remain -= x;
183 chars += x;
184 pad = 15 - x; /* pad device type to be exactly 15 chars */
185 for (i = 0; i < pad; i++)
186 VBUSCHANNEL_ADDACHAR(' ', p, remain, chars);
187 VBUSCHANNEL_ADDACHAR(' ', p, remain, chars);
188
189 /* emit driver name */
190 psrc = &devinfo->drvname[0];
191 nsrc = sizeof(devinfo->drvname);
192 x = vbuschannel_sanitize_buffer(p, remain, psrc, nsrc);
193 p += x;
194 remain -= x;
195 chars += x;
196 pad = 15 - x; /* pad driver name to be exactly 15 chars */
197 for (i = 0; i < pad; i++)
198 VBUSCHANNEL_ADDACHAR(' ', p, remain, chars);
199 VBUSCHANNEL_ADDACHAR(' ', p, remain, chars);
200
201 /* emit strings */
202 psrc = &devinfo->infostrs[0];
203 nsrc = sizeof(devinfo->infostrs);
204 x = vbuschannel_sanitize_buffer(p, remain, psrc, nsrc);
205 p += x;
206 remain -= x;
207 chars += x;
208 VBUSCHANNEL_ADDACHAR('\n', p, remain, chars);
209
210 return chars;
211 }
212
213 #endif
214