plan9fox/sys/src/cmd/io.c

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2011-04-15 19:01:29 +00:00
#include <u.h>
#include <libc.h>
const char const * datac[] = {0,"#P/iob","#P/iow",0,"#P/iol",0,0,0,"#P/msr"};
void
main(int argc, char** argv) {
int fd, size, op;
ulong port;
uvlong data;
uchar datab[8];
data = 0;
size = 1;
op = -1;
ARGBEGIN {
case 'W': size = 2; break;
case 'L': size = 4; break;
case 'M': size = 8; break;
case 'r': op = OREAD; break;
case 'w': op = OWRITE; break;
default: sysfatal("bad flag %c", ARGC());
} ARGEND;
if(op == -1) sysfatal("no operation selected");
if(argc < 1) sysfatal("no port selected");
if(op == OWRITE && argc < 2) sysfatal("no data selected");
port = strtoul(argv[0], 0, 0);
if(op == OWRITE) data = strtoull(argv[1], 0, 0);
fd = open(datac[size], op);
if(fd == -1) sysfatal("open: %r");
if(op == OWRITE) {
datab[0] = data;
datab[1] = data >> 8;
datab[2] = data >> 16;
datab[3] = data >> 24;
datab[4] = data >> 32;
datab[5] = data >> 40;
datab[6] = data >> 48;
datab[7] = data >> 56;
if(pwrite(fd, datab, size, port) != size)
sysfatal("pwrite: %r");
}
else {
memset(datab, 0, 8);
if(pread(fd, datab, size, port) != size)
sysfatal("pread: %r");
data = datab[0] | (datab[1] << 8) | (datab[2] << 16) |
(datab[3] << 24) | ((vlong)datab[4] << 32) |
((vlong)datab[5] << 40) | ((vlong)datab[6] << 48) |
((vlong)datab[7] << 56);
print("0x%llx\n", data);
}
exits(nil);
}