new usbdiskdirect driver

git-svn-id: https://svn.code.sf.net/p/gphoto/code/trunk/libgphoto2@12751 67ed7778-7388-44ab-90cf-0a291f65f57c

1 files changed, 426 insertions, 0 deletions

diff --git a/libgphoto2_port/usbdiskdirect/linux.c b/libgphoto2_port/usbdiskdirect/linux.c
new file mode 100644
index 000000000..747316b86
--- /dev/null
+++ b/libgphoto2_port/usbdiskdirect/linux.c
@@ -0,0 +1,426 @@
+/* Direct IO to USB Mass storage devices port library for Linux
+ * 
+ *   Copyright (c) 2010 Hans de Goede <hdegoede@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser 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 "config.h"
+#include <gphoto2/gphoto2-port-library.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/param.h>
+#ifdef HAVE_LOCKDEV
+#  include <lockdev.h>
+#endif
+
+#include <gphoto2/gphoto2-port-result.h>
+#include <gphoto2/gphoto2-port-log.h>
+#include <gphoto2/gphoto2-port.h>
+
+#ifdef ENABLE_NLS
+#  include <libintl.h>
+#  undef _
+#  define _(String) dgettext (GETTEXT_PACKAGE, String)
+#  ifdef gettext_noop
+#    define N_(String) gettext_noop (String)
+#  else
+#    define N_(String) (String)
+#  endif 
+#else
+#  define textdomain(String) (String)
+#  define gettext(String) (String)
+#  define dgettext(Domain,Message) (Message)
+#  define dcgettext(Domain,Message,Type) (Message)
+#  define bindtextdomain(Domain,Directory) (Domain)
+#  define _(String) (String)
+#  define N_(String) (String)
+#endif
+
+/* From Linux asm/fcntl.h */
+#ifndef O_DIRECT
+#define O_DIRECT        00040000        /* direct disk access hint */
+#endif
+
+#define CHECK(result) {int r=(result); if (r<0) return (r);}
+
+struct _GPPortPrivateLibrary {
+	int fd;       /* Device handle */
+};
+
+GPPortType
+gp_port_library_type () 
+{
+	return GP_PORT_USB_DISK_DIRECT;
+}
+
+static int
+gp_port_usbdiskdirect_lock (GPPort *port, const char *path)
+{
+#ifdef HAVE_LOCKDEV
+	int pid;
+
+	gp_log (GP_LOG_DEBUG, "gphoto2-port-usbdiskdirect",
+		"Trying to lock '%s'...", path);
+
+	pid = dev_lock (path);
+	if (pid) {
+		if (port) {
+			if (pid > 0)
+				gp_port_set_error (port, _("Device '%s' is "
+					"locked by pid %d"), path, pid);
+			else
+				gp_port_set_error (port, _("Device '%s' could "
+					"not be locked (dev_lock returned "
+					"%d)"), path, pid);
+		}
+		return GP_ERROR_IO_LOCK;
+	}
+#else
+# ifdef __GCC__
+#  warning No locking library found. 
+#  warning You will run into problems if you use
+#  warning gphoto2 with a usbdiskdirect picframe in 
+#  warning combination with Konqueror (KDE) or Nautilus (GNOME).
+#  warning This will *not* concern USB cameras.
+# endif
+#endif
+
+	return GP_OK;
+}
+
+static int
+gp_port_usbdiskdirect_unlock (GPPort *port, const char *path)
+{
+#ifdef HAVE_LOCKDEV
+	int pid;
+
+	pid = dev_unlock (path, 0);
+	if (pid) {
+		if (port) {
+			if (pid > 0)
+				gp_port_set_error (port, _("Device '%s' could "
+					"not be unlocked as it is locked by "
+					"pid %d."), path, pid);
+			else
+				gp_port_set_error (port, _("Device '%s' could "
+					"not be unlocked (dev_unlock "
+					"returned %d)"), path, pid);
+		}
+		return GP_ERROR_IO_LOCK;
+	}
+#endif /* !HAVE_LOCKDEV */
+
+	return GP_OK;
+}
+
+static const char *
+gp_port_usbdiskdirect_resolve_symlink (const char *link)
+{
+	ssize_t ret;
+	static char path[PATH_MAX + 1];
+	char *slash, buf[PATH_MAX + 1];
+	struct stat st;
+	int len;
+
+	snprintf (path, sizeof(path), "%s", link);
+
+	do {
+		ret = readlink (path, buf, PATH_MAX);
+		if (ret < 0)
+			return NULL;
+		buf[ret] = 0;
+
+		slash = strrchr (path, '/');
+		if (buf[0] == '/' || slash == NULL) {
+			snprintf (path, sizeof(path), "%s", buf);
+		} else {
+			*slash = 0;
+			len = strlen (path);
+			snprintf (path + len, sizeof (path) - len, "/%s", buf);
+		}
+
+		if (stat (path, &st))
+			return NULL;
+	} while (S_ISLNK(st.st_mode));
+
+	return path;
+}
+
+static int 
+gp_port_usbdiskdirect_get_usb_id (const char *disk,
+	unsigned short *vendor_id, unsigned short *product_id)
+{
+	FILE *f;
+	char c, *s, buf[32], path[PATH_MAX + 1];
+
+	snprintf (path, sizeof (path), "/sys/block/%s", disk);
+	snprintf (path, sizeof (path), "%s/../../../../../modalias",
+		  gp_port_usbdiskdirect_resolve_symlink(path));
+
+	f = fopen (path, "r");
+	if (!f)
+		return GP_ERROR_IO_SUPPORTED_USB;
+
+	s = fgets (buf, sizeof(buf), f);
+	fclose (f);
+
+	if (!s)
+		return GP_ERROR_IO_SUPPORTED_USB;
+
+	if (sscanf (s, "usb:v%4hxp%4hx%c", vendor_id, product_id, &c) != 3 ||
+	    c != 'd')
+		return GP_ERROR_IO_SUPPORTED_USB;
+
+	return GP_OK;
+}
+
+int
+gp_port_library_list (GPPortInfoList *list)
+{
+	DIR *dir;
+	struct dirent *dirent;
+	GPPortInfo info;
+	unsigned short vendor_id, product_id;
+
+	gp_port_info_new (&info);
+	dir = opendir ("/sys/block");
+	if (dir == NULL)
+		return GP_OK;
+
+	while ((dirent = readdir (dir))) {
+		char path[4096];
+		if (dirent->d_name[0] != 's' ||
+		    dirent->d_name[1] != 'd' ||
+		    dirent->d_name[2] < 'a' ||
+		    dirent->d_name[2] > 'z')
+			continue;
+
+		if (gp_port_usbdiskdirect_get_usb_id (dirent->d_name,
+				&vendor_id, &product_id) != GP_OK)
+			continue; /* Not a usb device */
+
+		gp_port_info_set_type (info, GP_PORT_USB_DISK_DIRECT);
+		snprintf (path, sizeof (path),
+			  "usbdiskdirect:/dev/%s",
+			  dirent->d_name);
+		gp_port_info_set_path (info, path);
+		gp_port_info_set_name (info, _("USB Mass Storage direct IO"));
+		CHECK (gp_port_info_list_append (list, info))
+	}
+	return GP_OK;
+}
+
+static int
+gp_port_usbdiskdirect_init (GPPort *port)
+{
+	port->pl = calloc (1, sizeof (GPPortPrivateLibrary));
+	if (!port->pl)
+		return GP_ERROR_NO_MEMORY;
+
+	port->pl->fd = -1;
+
+	return GP_OK;
+}
+
+static int
+gp_port_usbdiskdirect_exit (GPPort *port)
+{
+	if (!port)
+		return GP_ERROR_BAD_PARAMETERS;
+
+	if (port->pl) {
+		free (port->pl);
+		port->pl = NULL;
+	}
+
+	return GP_OK;
+}
+
+static int
+gp_port_usbdiskdirect_open (GPPort *port)
+{
+	int result, i;
+	const int max_tries = 5;
+	const char *path = port->settings.usbdiskdirect.path;
+
+	result = gp_port_usbdiskdirect_lock (port, path);
+	if (result != GP_OK) {
+		for (i = 0; i < max_tries; i++) {
+			result = gp_port_usbdiskdirect_lock (port, path);
+			if (result == GP_OK)
+				break;
+			gp_log (GP_LOG_DEBUG, "gphoto2-port-usbdiskdirect",
+				"Failed to get a lock, trying again...");
+			sleep (1);
+		}
+		CHECK (result)
+	}
+	port->pl->fd = open (path, O_RDWR|O_DIRECT|O_SYNC);
+	if (port->pl->fd == -1) {
+		gp_port_usbdiskdirect_unlock (port, path);
+		gp_port_set_error (port, _("Failed to open '%s' (%m)."), path);
+		return GP_ERROR_IO;
+	}
+
+	return GP_OK;
+}
+
+static int
+gp_port_usbdiskdirect_close (GPPort *port)
+{
+	if (!port || port->pl->fd == -1)
+		return GP_OK;
+
+	if (close (port->pl->fd) == -1) {
+		gp_port_set_error (port, _("Could not close "
+			"'%s' (%m)."), port->settings.usbdiskdirect.path);
+		return GP_ERROR_IO;
+	}
+	port->pl->fd = -1;
+
+	CHECK (gp_port_usbdiskdirect_unlock (port,
+					port->settings.usbdiskdirect.path))
+
+	return GP_OK;
+}
+
+static int gp_port_usbdiskdirect_seek (GPPort *port, int offset, int whence)
+{
+	off_t ret;
+
+	if (!port)
+		return GP_ERROR_BAD_PARAMETERS;
+
+	/* The device needs to be opened for that operation */
+	if (port->pl->fd == -1)
+		CHECK (gp_port_usbdiskdirect_open (port))
+
+	ret = lseek (port->pl->fd, offset, whence);
+	if (ret == -1) {
+		gp_port_set_error (port, _("Could not seek to offset: %x on "
+			"'%s' (%m)."), offset,
+			port->settings.usbdiskdirect.path);
+		return GP_ERROR_IO;
+	}
+
+	return ret;
+}
+
+static int
+gp_port_usbdiskdirect_write (GPPort *port, const char *bytes, int size)
+{
+	int ret;
+
+	if (!port)
+		return GP_ERROR_BAD_PARAMETERS;
+
+	/* The device needs to be opened for that operation */
+	if (port->pl->fd == -1)
+		CHECK (gp_port_usbdiskdirect_open (port))
+
+	ret = write (port->pl->fd, bytes, size);
+	if (ret < 0) {
+		gp_port_set_error (port, _("Could not write to '%s' (%m)."),
+				   port->settings.usbdiskdirect.path);
+		return GP_ERROR_IO;
+	}
+
+	return ret;
+}
+
+static int
+gp_port_usbdiskdirect_read (GPPort *port, char *bytes, int size)
+{
+	int ret;
+
+	if (!port)
+		return GP_ERROR_BAD_PARAMETERS;
+
+	/* The device needs to be opened for that operation */
+	if (port->pl->fd == -1)
+		CHECK (gp_port_usbdiskdirect_open (port))
+
+	ret = read (port->pl->fd, bytes, size);
+	if (ret < 0) {
+		gp_port_set_error (port, _("Could not read from '%s' (%m)."),
+				   port->settings.usbdiskdirect.path);
+		return GP_ERROR_IO;
+	}
+
+	return ret;
+}
+
+static int
+gp_port_usbdiskdirect_update (GPPort *port)
+{
+	if (!port)
+		return GP_ERROR_BAD_PARAMETERS;
+
+	memcpy (&port->settings, &port->settings_pending,
+		sizeof (port->settings));
+
+	return GP_OK;
+}
+
+static int
+gp_port_usbdiskdirect_find_device(GPPort *port, int idvendor, int idproduct)
+{
+	unsigned short vendor_id, product_id;
+	const char *disk;
+
+	if (!port)
+		return GP_ERROR_BAD_PARAMETERS;
+
+	disk = strrchr (port->settings.usbdiskdirect.path, '/');
+	if (!disk)
+		return GP_ERROR_BAD_PARAMETERS;
+	disk++;
+
+	CHECK (gp_port_usbdiskdirect_get_usb_id (disk,
+						 &vendor_id, &product_id))
+	if (vendor_id != idvendor || product_id != idproduct)
+		return GP_ERROR_IO_USB_FIND;
+
+	return GP_OK;
+}
+
+GPPortOperations *
+gp_port_library_operations ()
+{
+	GPPortOperations *ops;
+
+	ops = malloc (sizeof (GPPortOperations));
+	if (!ops)
+		return (NULL);
+	memset (ops, 0, sizeof (GPPortOperations)); 
+
+	ops->init   = gp_port_usbdiskdirect_init;
+	ops->exit   = gp_port_usbdiskdirect_exit;
+	ops->open   = gp_port_usbdiskdirect_open;
+	ops->close  = gp_port_usbdiskdirect_close;
+	ops->seek   = gp_port_usbdiskdirect_seek;
+	ops->read   = gp_port_usbdiskdirect_read;
+	ops->write  = gp_port_usbdiskdirect_write;
+	ops->update = gp_port_usbdiskdirect_update;
+	ops->find_device = gp_port_usbdiskdirect_find_device;
+
+	return (ops);
+}