Support for <device file> option when doing --device-list

- simple-mtpfs can be used as lightweight crossplatform mtp-probe
- at current state simple-mtpfs does not respect libmtp device quirks
  when connecting via device file. That leads to errors on some devices
  This issue can be workarounded now with following command:
     simple-mtpfs --device `simple-mtpfs <device file> -l | cut -f1 -d:` <mount point>

man/simple-mtpfs.1

@@ -30,7 +30,7 @@ print version
 .SS "SIMPLE-MTPFS options:"
 .TP
 \fB\-l\fR   \fB\-\-list\-devices\fR
-list available MTP devices
+list available MTP devices. Supports \fB<device>\fR option
 .TP
      \fB\-\-device\fR
 select device no. to mount

src/simple-mtpfs-fuse.cpp

@@ -180,15 +180,16 @@ int SMTPFileSystem::SMTPFileSystemOptions::opt_proc(void *data, const char *arg,
     SMTPFileSystemOptions *options = static_cast<SMTPFileSystemOptions*>(data);
 
     if (key == FUSE_OPT_KEY_NONOPT) {
-        if (options->m_mount_point && !options->m_device_file) {
-            options->m_device_file = options->m_mount_point;
-            options->m_mount_point = nullptr;
-        } else if (options->m_mount_point && options->m_device_file) {
+        if (options->m_mount_point && options->m_device_file) {
             // Unknown positional argument supplied
             return -1;
         }
+        if (options->m_device_file) {
+            fuse_opt_add_opt(&options->m_mount_point, arg);
+            return 0;
+        }
 
-        fuse_opt_add_opt(&options->m_mount_point, arg);
+        fuse_opt_add_opt(&options->m_device_file, arg);
         return 0;
     }
     return 1;
@@ -287,6 +288,11 @@ bool SMTPFileSystem::parseOptions(int argc, char **argv)
         return true;
     }
 
+    if (m_options.m_device_file && !m_options.m_mount_point) {
+        m_options.m_mount_point = m_options.m_device_file;
+        m_options.m_device_file = nullptr;
+    }
+
     if (!m_options.m_mount_point) {
         logerr("Mount point missing.\n");
         m_options.m_good = false;
@@ -326,7 +332,7 @@ void SMTPFileSystem::printHelp() const
         << "    -V   --version         print version\n\n"
         << "simple-mtpfs options:\n"
         << "    -v   --verbose         verbose output, implies -f\n"
-        << "    -l   --list-devices    print available devices\n"
+        << "    -l   --list-devices    print available devices. Supports <source> option\n"
         << "         --device          select a device number to mount\n"
         << "    -o enable-move         enable the move operations\n\n";
     fuse_opt_add_arg(&args, m_args.argv[0]);
@@ -350,7 +356,9 @@ void SMTPFileSystem::printVersion() const
 
 bool SMTPFileSystem::listDevices() const
 {
-    return MTPDevice::listDevices(m_options.m_verbose);
+    const std::string dev_file = m_options.m_device_file ? m_options.m_device_file : "";
+
+    return MTPDevice::listDevices(m_options.m_verbose, dev_file);
 }
 
 bool SMTPFileSystem::exec()

src/simple-mtpfs-mtp-device.cpp

@@ -646,10 +646,11 @@ MTPDevice::Capabilities MTPDevice::getCapabilities(const MTPDevice &device)
     return capabilities;
 }
 
-bool MTPDevice::listDevices(bool verbose)
+bool MTPDevice::listDevices(bool verbose, const std::string &dev_file)
 {
     int raw_devices_cnt;
     LIBMTP_raw_device_t *raw_devices;
+    std::string dev_path;
 
     // Do not output LIBMTP debug stuff
     StreamHelper::off();
@@ -663,7 +664,18 @@ bool MTPDevice::listDevices(bool verbose)
         return false;
     }
 
+    if (!dev_file.empty()) {
+        dev_path = smtpfs_realpath(dev_file);
+        if (dev_path.empty()) {
+            std::cerr << "Can not open such device '" << dev_file << "'.\n";
+            return false;
+        }
+    }
+
     for (int i = 0; i < raw_devices_cnt; ++i) {
+        if (!dev_file.empty() &&
+            dev_path != smtpfs_usb_devpath(raw_devices[i].bus_location, raw_devices[i].devnum))
+            continue;
         std::cout << i + 1 << ": "
             << (raw_devices[i].device_entry.vendor ? raw_devices[i].device_entry.vendor : "Unknown vendor ")
             << (raw_devices[i].device_entry.product ? raw_devices[i].device_entry.product : "Unknown product")

src/simple-mtpfs-mtp-device.h

@@ -85,7 +85,7 @@ public:
 
     Capabilities getCapabilities() const;
 
-    static bool listDevices(bool verbose = false);
+    static bool listDevices(bool verbose, const std::string &dev_file);
 
 private:
     void criticalEnter() { m_device_mutex.lock(); }