linux_module_learn/examples/misc-progs/inp.c

130 lines
3.3 KiB
C

/*
* inp.c -- read all the ports specified in hex on the command line.
* The program uses the faster ioperm/iopl calls on x86, /dev/port
* on other platforms. The program acts as inb/inw/inl according
* to its own name
*
* Copyright (C) 1998,2000,2001 Alessandro Rubini
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <asm/io.h> /* linux-specific */
#ifdef __GLIBC__
# include <sys/perm.h>
#endif
#define PORT_FILE "/dev/port"
char *prgname;
#ifdef __i386__
static int read_and_print_one(unsigned int port,int size)
{
static int iopldone = 0;
if (port > 1024) {
if (!iopldone && iopl(3)) {
fprintf(stderr, "%s: iopl(): %s\n", prgname, strerror(errno));
return 1;
}
iopldone++;
} else if (ioperm(port,size,1)) {
fprintf(stderr, "%s: ioperm(%x): %s\n", prgname,
port, strerror(errno));
return 1;
}
if (size == 4)
printf("%04x: %08x\n", port, inl(port));
else if (size == 2)
printf("%04x: %04x\n", port, inw(port));
else
printf("%04x: %02x\n", port, inb(port));
return 0;
}
#else /* not i386 */
static int read_and_print_one(unsigned int port,int size)
{
static int fd = -1;
unsigned char b; unsigned short w; unsigned int l;
if (fd < 0)
fd = open(PORT_FILE, O_RDONLY);
if (fd < 0) {
fprintf(stderr, "%s: %s: %s\n", prgname, PORT_FILE, strerror(errno));
return 1;
}
lseek(fd, port, SEEK_SET);
if (size == 4) {
read(fd, &l, 4);
printf("%04x: 0x%08x\n", port, l);
} else if (size == 2) {
read(fd, &w, 2);
printf("%04x: 0x%04x\n", port, w & 0xffff);
} else {
read(fd, &b, 1);
printf("%04x: 0x%02x\n", port, b & 0xff);
}
return 0;
}
#endif /* i386 */
int main(int argc, char **argv)
{
unsigned int i, n, port, size, error = 0;
prgname = argv[0];
/* find the data size */
switch (prgname[strlen(prgname)-1]) {
case 'w': size = 2; break;
case 'l': size = 4; break;
case 'b': case 'p': default:
size = 1;
}
setuid(0); /* if we're setuid, force it on */
for (i = 1; i < argc; i++) {
if ( sscanf(argv[i], "%x%n", &port, &n) < 1
|| n != strlen(argv[i]) ) {
fprintf(stderr, "%s: argument \"%s\" is not a hex number\n",
argv[0], argv[i]);
error++; continue;
}
if (port & (size-1)) {
fprintf(stderr, "%s: argument \"%s\" is not properly aligned\n",
argv[0], argv[i]);
error++; continue;
}
error += read_and_print_one(port, size);
}
exit (error ? 1 : 0);
}