diff options
Diffstat (limited to 'drivers/staging/unisys/visorbus/vbuschannel.h')
| -rw-r--r-- | drivers/staging/unisys/visorbus/vbuschannel.h | 211 |
1 files changed, 210 insertions, 1 deletions
diff --git a/drivers/staging/unisys/visorbus/vbuschannel.h b/drivers/staging/unisys/visorbus/vbuschannel.h index 90fa12e62f26..e97917522f6a 100644 --- a/drivers/staging/unisys/visorbus/vbuschannel.h +++ b/drivers/staging/unisys/visorbus/vbuschannel.h @@ -23,7 +23,6 @@ * the client devices and client drivers for the server end to see. */ #include <linux/uuid.h> -#include "vbusdeviceinfo.h" #include "channel.h" /* {193b331b-c58f-11da-95a9-00e08161165f} */ @@ -58,6 +57,216 @@ static const uuid_le spar_vbus_channel_protocol_uuid = actual_bytes)) #pragma pack(push, 1) /* both GCC and VC now allow this pragma */ + +/* + * An array of this struct is present in the channel area for each vbus. + * (See vbuschannel.h.) + * It is filled in by the client side to provide info about the device + * and driver from the client's perspective. + */ +struct ultra_vbus_deviceinfo { + u8 devtype[16]; /* short string identifying the device type */ + u8 drvname[16]; /* driver .sys file name */ + u8 infostrs[96]; /* kernel version */ + u8 reserved[128]; /* pad size to 256 bytes */ +}; + +/** + * vbuschannel_sanitize_buffer() - remove non-printable chars from buffer + * @p: destination buffer where chars are written to + * @remain: number of bytes that can be written starting at #p + * @src: pointer to source buffer + * @srcmax: number of valid characters at #src + * + * Reads chars from the buffer at @src for @srcmax bytes, and writes to + * the buffer at @p, which is @remain bytes long, ensuring never to + * overflow the buffer at @p, using the following rules: + * - printable characters are simply copied from the buffer at @src to the + * buffer at @p + * - intervening streaks of non-printable characters in the buffer at @src + * are replaced with a single space in the buffer at @p + * Note that we pay no attention to '\0'-termination. + * + * Pass @p == NULL and @remain == 0 for this special behavior -- In this + * case, we simply return the number of bytes that WOULD HAVE been written + * to a buffer at @p, had it been infinitely big. + * + * Return: the number of bytes written to @p (or WOULD HAVE been written to + * @p, as described in the previous paragraph) + */ +static inline int +vbuschannel_sanitize_buffer(char *p, int remain, char *src, int srcmax) +{ + int chars = 0; + int nonprintable_streak = 0; + + while (srcmax > 0) { + if ((*src >= ' ') && (*src < 0x7f)) { + if (nonprintable_streak) { + if (remain > 0) { + *p = ' '; + p++; + remain--; + chars++; + } else if (!p) { + chars++; + } + nonprintable_streak = 0; + } + if (remain > 0) { + *p = *src; + p++; + remain--; + chars++; + } else if (!p) { + chars++; + } + } else { + nonprintable_streak = 1; + } + src++; + srcmax--; + } + return chars; +} + +#define VBUSCHANNEL_ADDACHAR(ch, p, remain, chars) \ + do { \ + if (remain <= 0) \ + break; \ + *p = ch; \ + p++; chars++; remain--; \ + } while (0) + +/** + * vbuschannel_itoa() - convert non-negative int to string + * @p: destination string + * @remain: max number of bytes that can be written to @p + * @num: input int to convert + * + * Converts the non-negative value at @num to an ascii decimal string + * at @p, writing at most @remain bytes. Note there is NO '\0' termination + * written to @p. + * + * Return: number of bytes written to @p + * + */ +static inline int +vbuschannel_itoa(char *p, int remain, int num) +{ + int digits = 0; + char s[32]; + int i; + + if (num == 0) { + /* '0' is a special case */ + if (remain <= 0) + return 0; + *p = '0'; + return 1; + } + /* form a backwards decimal ascii string in <s> */ + while (num > 0) { + if (digits >= (int)sizeof(s)) + return 0; + s[digits++] = (num % 10) + '0'; + num = num / 10; + } + if (remain < digits) { + /* not enough room left at <p> to hold number, so fill with + * '?' + */ + for (i = 0; i < remain; i++, p++) + *p = '?'; + return remain; + } + /* plug in the decimal ascii string representing the number, by */ + /* reversing the string we just built in <s> */ + i = digits; + while (i > 0) { + i--; + *p = s[i]; + p++; + } + return digits; +} + +/** + * vbuschannel_devinfo_to_string() - format a struct ultra_vbus_deviceinfo + * to a printable string + * @devinfo: the struct ultra_vbus_deviceinfo to format + * @p: destination string area + * @remain: size of destination string area in bytes + * @devix: the device index to be included in the output data, or -1 if no + * device index is to be included + * + * Reads @devInfo, and converts its contents to a printable string at @p, + * writing at most @remain bytes. Note there is NO '\0' termination + * written to @p. + * + * Return: number of bytes written to @p + */ +static inline int +vbuschannel_devinfo_to_string(struct ultra_vbus_deviceinfo *devinfo, + char *p, int remain, int devix) +{ + char *psrc; + int nsrc, x, i, pad; + int chars = 0; + + psrc = &devinfo->devtype[0]; + nsrc = sizeof(devinfo->devtype); + if (vbuschannel_sanitize_buffer(NULL, 0, psrc, nsrc) <= 0) + return 0; + + /* emit device index */ + if (devix >= 0) { + VBUSCHANNEL_ADDACHAR('[', p, remain, chars); + x = vbuschannel_itoa(p, remain, devix); + p += x; + remain -= x; + chars += x; + VBUSCHANNEL_ADDACHAR(']', p, remain, chars); + } else { + VBUSCHANNEL_ADDACHAR(' ', p, remain, chars); + VBUSCHANNEL_ADDACHAR(' ', p, remain, chars); + VBUSCHANNEL_ADDACHAR(' ', p, remain, chars); + } + + /* emit device type */ + x = vbuschannel_sanitize_buffer(p, remain, psrc, nsrc); + p += x; + remain -= x; + chars += x; + pad = 15 - x; /* pad device type to be exactly 15 chars */ + for (i = 0; i < pad; i++) + VBUSCHANNEL_ADDACHAR(' ', p, remain, chars); + VBUSCHANNEL_ADDACHAR(' ', p, remain, chars); + + /* emit driver name */ + psrc = &devinfo->drvname[0]; + nsrc = sizeof(devinfo->drvname); + x = vbuschannel_sanitize_buffer(p, remain, psrc, nsrc); + p += x; + remain -= x; + chars += x; + pad = 15 - x; /* pad driver name to be exactly 15 chars */ + for (i = 0; i < pad; i++) + VBUSCHANNEL_ADDACHAR(' ', p, remain, chars); + VBUSCHANNEL_ADDACHAR(' ', p, remain, chars); + + /* emit strings */ + psrc = &devinfo->infostrs[0]; + nsrc = sizeof(devinfo->infostrs); + x = vbuschannel_sanitize_buffer(p, remain, psrc, nsrc); + p += x; + remain -= x; + chars += x; + VBUSCHANNEL_ADDACHAR('\n', p, remain, chars); + + return chars; +} + struct spar_vbus_headerinfo { u32 struct_bytes; /* size of this struct in bytes */ u32 device_info_struct_bytes; /* sizeof(ULTRA_VBUS_DEVICEINFO) */ |