haiku/src/bin/diskimage.cpp
Ingo Weinhold 6cc1f01511 Implemented small tool diskimage, which allows to register/unregister files
as disk devices. It also demonstrates that the respective devfs functionality
is utterly broken.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@33384 a95241bf-73f2-0310-859d-f6bbb57e9c96
2009-10-01 03:05:06 +00:00

247 lines
6.0 KiB
C++

/*
* Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
* Distributed under the terms of the MIT License.
*/
#include <errno.h>
#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
#include <DiskDevice.h>
#include <DiskDeviceRoster.h>
#include <Path.h>
extern const char* __progname;
const char* kCommandName = __progname;
static const char* kUsage =
"Usage: %s register <file>\n"
" %s unregister ( <file> | <device path> | <device ID> )\n"
" %s list\n"
"Registers a regular file as disk device, unregisters an already "
"registered\n"
"one, or lists all file disk devices.\n"
"\n"
"Options:\n"
" -h, --help - Print this usage info.\n"
;
static void
print_usage_and_exit(bool error)
{
fprintf(error ? stderr : stdout, kUsage, kCommandName, kCommandName,
kCommandName);
exit(error ? 1 : 0);
}
static status_t
list_file_disk_devices()
{
printf(" ID File Device\n");
printf("------------------------------------------------------------------"
"-------------\n");
BDiskDeviceRoster roster;
BDiskDevice device;
while (roster.GetNextDevice(&device) == B_OK) {
if (!device.IsFile())
continue;
// ID
printf("%6ld ", device.ID());
// file path
BPath path;
printf("%-35s",
device.GetFilePath(&path) == B_OK ? path.Path() : "???");
// device path
printf("%s", device.GetPath(&path) == B_OK ? path.Path() : "???");
printf("\n");
}
return B_OK;
}
static status_t
register_file_disk_device(const char* fileName)
{
// stat() the file to verify that it's a regular file
struct stat st;
if (lstat(fileName, &st) != 0) {
status_t error = errno;
fprintf(stderr, "Error: Failed to stat() \"%s\": %s\n", fileName,
strerror(error));
return error;
}
if (!S_ISREG(st.st_mode)) {
fprintf(stderr, "Error: \"%s\" is not a regular file.\n", fileName);
return B_BAD_VALUE;
}
// register the file
BDiskDeviceRoster roster;
partition_id id = roster.RegisterFileDevice(fileName);
if (id < 0) {
fprintf(stderr, "Error: Failed to register file disk device: %s\n",
strerror(id));
return id;
}
// print the success message (get the device path)
BDiskDevice device;
BPath path;
if (roster.GetDeviceWithID(id, &device) == B_OK
&& device.GetPath(&path) == B_OK) {
printf("Registered file as disk device \"%s\" with ID %ld.\n",
path.Path(), id);
} else {
printf("Registered file as disk device with ID %ld, but failed to "
"get the device path.\n", id);
}
return B_OK;
}
static status_t
unregister_file_disk_device(const char* fileNameOrID)
{
// try to parse the parameter as ID
char* numberEnd;
partition_id id = strtol(fileNameOrID, &numberEnd, 0);
BDiskDeviceRoster roster;
if (id >= 0 && numberEnd != fileNameOrID && *numberEnd == '\0') {
BDiskDevice device;
if (roster.GetDeviceWithID(id, &device) == B_OK && device.IsFile()) {
status_t error = roster.UnregisterFileDevice(id);
if (error != B_OK) {
fprintf(stderr, "Error: Failed to unregister file disk device "
"with ID %ld: %s\n", id, strerror(error));
return error;
}
printf("Unregistered file disk device with ID %ld.\n", id);
return B_OK;
} else {
fprintf(stderr, "No file disk device with ID %ld, trying file "
"\"%s\"\n", id, fileNameOrID);
}
}
// the parameter must be a file name -- stat() it
struct stat st;
if (lstat(fileNameOrID, &st) != 0) {
status_t error = errno;
fprintf(stderr, "Error: Failed to stat() \"%s\": %s\n", fileNameOrID,
strerror(error));
return error;
}
// remember the volume and node ID, so we can identify the file
// NOTE: There's a race condition -- we would need to open the file and
// keep it open to avoid it.
dev_t volumeID = st.st_dev;
ino_t nodeID = st.st_ino;
// iterate through all file disk devices and try to find a match
BDiskDevice device;
while (roster.GetNextDevice(&device) == B_OK) {
if (!device.IsFile())
continue;
// get file path and stat it, same for the device path
BPath path;
bool isFilePath = true;
if ((device.GetFilePath(&path) == B_OK && lstat(path.Path(), &st) == 0
&& volumeID == st.st_dev && nodeID == st.st_ino)
|| (isFilePath = false, false)
|| (device.GetPath(&path) == B_OK && lstat(path.Path(), &st) == 0
&& volumeID == st.st_dev && nodeID == st.st_ino)) {
status_t error = roster.UnregisterFileDevice(device.ID());
if (error != B_OK) {
fprintf(stderr, "Error: Failed to unregister file disk device"
"%s \"%s\" (ID: %ld): %s\n", isFilePath ? " for file" : "",
fileNameOrID, device.ID(), strerror(error));
return error;
}
printf("Unregistered file disk device%s \"%s\" (ID: %ld)\n",
isFilePath ? " for file" : "", fileNameOrID, device.ID());
return B_OK;
}
}
fprintf(stderr, "Error: \"%s\" does not refer to a file disk device.\n",
fileNameOrID);
return B_BAD_VALUE;
}
int
main(int argc, const char* const* argv)
{
while (true) {
static struct option sLongOptions[] = {
{ "help", no_argument, 0, 'h' },
{ 0, 0, 0, 0 }
};
opterr = 0; // don't print errors
int c = getopt_long(argc, (char**)argv, "+h", sLongOptions, NULL);
if (c == -1)
break;
switch (c) {
case 'h':
print_usage_and_exit(false);
break;
default:
print_usage_and_exit(true);
break;
}
}
// Of the remaining arguments the next one should be the command.
if (optind >= argc)
print_usage_and_exit(true);
status_t error = B_OK;
const char* command = argv[optind++];
if (strcmp(command, "list") == 0) {
if (optind < argc)
print_usage_and_exit(true);
list_file_disk_devices();
} else if (strcmp(command, "register") == 0) {
if (optind + 1 != argc)
print_usage_and_exit(true);
const char* fileName = argv[optind++];
register_file_disk_device(fileName);
} else if (strcmp(command, "unregister") == 0) {
if (optind + 1 != argc)
print_usage_and_exit(true);
const char* fileName = argv[optind++];
unregister_file_disk_device(fileName);
} else
print_usage_and_exit(true);
return error == B_OK ? 0 : 1;
}