v4l2-apps: move libraries around to make the directory tree flatter

From: Hans Verkuil <hverkuil@xs4all.nl>

Instead of having libv4l2util in v4l2-apps/lib and libv4l in v4l2-apps/lib/libv4l,
both are now moved to v4l2-apps/libv4l2util and v4l2-apps/libv4l.

This is much cleaner and less confusing.

Priority: normal

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>

5 files changed, 1636 insertions, 0 deletions

diff --git a/v4l2-apps/libv4l/libv4l2/Makefile b/v4l2-apps/libv4l/libv4l2/Makefile
new file mode 100644
index 000000000..648d27c0c
--- /dev/null
+++ b/v4l2-apps/libv4l/libv4l2/Makefile
@@ -0,0 +1,82 @@
+override CPPFLAGS += -I../include -I../../../include -fvisibility=hidden
+
+CFLAGS := -g -O1
+CFLAGS += -Wall -Wno-unused -Wpointer-arith -Wstrict-prototypes -Wmissing-prototypes
+
+LIBS = -lpthread
+
+V4L2_OBJS     = libv4l2.o log.o
+V4L2CONVERT   = v4l2convert.so
+V4L2CONVERT_O = v4l2convert.o libv4l2.so
+TARGETS       = $(V4L2_LIB) libv4l2.pc
+INCLUDES      = ../include/libv4l2.h
+
+ifeq ($(LINKTYPE),static)
+V4L2_LIB      = libv4l2.a
+else
+V4L2_LIB      = libv4l2.so
+V4L2_OBJS    += ../libv4lconvert/libv4lconvert.so
+TARGETS      += $(V4L2CONVERT)
+override CPPFLAGS += -fPIC
+endif
+
+ifeq ($(LIB_RELEASE),)
+LIB_RELEASE = 0
+endif
+
+ifeq ($(PREFIX),)
+PREFIX = /usr/local
+endif
+
+ifeq ($(LIBDIR),)
+LIBDIR = $(PREFIX)/lib
+endif
+
+all: $(TARGETS)
+
+$(V4L2_LIB): $(V4L2_OBJS)
+
+$(V4L2CONVERT): $(V4L2CONVERT_O) $(V4L2_LIB)
+
+libv4l2.pc:
+	@echo prefix=$(PREFIX) > libv4l2.pc
+	@echo libdir=$(LIBDIR) >> libv4l2.pc
+	@echo >> libv4l2.pc
+	@echo 'Name: libv4l2' >> libv4l2.pc
+	@echo 'Description: v4l2 device access library' >> libv4l2.pc
+	@echo 'Version: '$(V4L2_LIB_VERSION) >> libv4l2.pc
+	@echo 'Requires: libv4lconvert' >> libv4l2.pc
+	@echo 'Libs: -L$${libdir} -lv4l2' >> libv4l2.pc
+	@echo 'Libs.private: -lpthread' >> libv4l2.pc
+	@echo 'Cflags: -I$${prefix}/include' >> libv4l2.pc
+
+install: all
+	mkdir -p $(DESTDIR)$(PREFIX)/include
+	install -p -m 644 $(INCLUDES) $(DESTDIR)$(PREFIX)/include
+ifeq ($(LINKTYPE),static)
+	mkdir -p $(DESTDIR)$(LIBDIR)
+	install -m 644 $(V4L2_LIB) $(DESTDIR)$(LIBDIR)
+else
+	mkdir -p $(DESTDIR)$(LIBDIR)/libv4l
+	install -m 755 $(V4L2_LIB).$(LIB_RELEASE) $(DESTDIR)$(LIBDIR)
+	cd $(DESTDIR)$(LIBDIR) && \
+	  ln -f -s $(V4L2_LIB).$(LIB_RELEASE) $(V4L2_LIB)
+	install -m 755 $(V4L2CONVERT).$(LIB_RELEASE) \
+	  $(DESTDIR)$(LIBDIR)/libv4l/$(V4L2CONVERT)
+endif
+	mkdir -p $(DESTDIR)$(LIBDIR)/pkgconfig
+	install -m 644 libv4l2.pc $(DESTDIR)$(LIBDIR)/pkgconfig
+
+clean::
+	rm -f *.a *.so* *.o *.d libv4l2.pc log *~
+
+%.o: %.c
+	$(CC) -c -MMD $(CPPFLAGS) $(CFLAGS) -o $@ $<
+
+%.so:
+	$(CC) -shared $(LDFLAGS) -Wl,-soname,$@.$(LIB_RELEASE) -o $@.$(LIB_RELEASE) $^ $(LIBS)
+	ln -f -s $@.$(LIB_RELEASE) $@
+
+%.a:
+	$(AR) cqs $@ $^
+
diff --git a/v4l2-apps/libv4l/libv4l2/libv4l2-priv.h b/v4l2-apps/libv4l/libv4l2/libv4l2-priv.h
new file mode 100644
index 000000000..8724832e1
--- /dev/null
+++ b/v4l2-apps/libv4l/libv4l2/libv4l2-priv.h
@@ -0,0 +1,95 @@
+/*
+#             (C) 2008 Hans de Goede <j.w.r.degoede@hhs.nl>
+
+# 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
+*/
+
+#ifndef __LIBV4L2_PRIV_H
+#define __LIBV4L2_PRIV_H
+
+#include <stdio.h>
+#include <pthread.h>
+#include <libv4lconvert.h> /* includes videodev2.h for us */
+
+/* On 32 bits archs we always use mmap2, on 64 bits archs there is no mmap2 */
+#ifdef __NR_mmap2
+#define SYS_mmap2 __NR_mmap2
+#define MMAP2_PAGE_SHIFT 12
+#else
+#define SYS_mmap2 SYS_mmap
+#define MMAP2_PAGE_SHIFT 0
+#endif
+
+#define V4L2_MAX_DEVICES 16
+/* Warning when making this larger the frame_queued and frame_mapped members of
+   the v4l2_dev_info struct can no longer be a bitfield, so the code needs to
+   be adjusted! */
+#define V4L2_MAX_NO_FRAMES 32
+#define V4L2_DEFAULT_NREADBUFFERS 4
+#define V4L2_FRAME_BUF_SIZE (4096 * 4096)
+
+#define V4L2_LOG_ERR(...) \
+  do { \
+    if (v4l2_log_file) { \
+      fprintf(v4l2_log_file, "libv4l2: error " __VA_ARGS__); \
+      fflush(v4l2_log_file); \
+    } else \
+      fprintf(stderr, "libv4l2: error " __VA_ARGS__); \
+  } while(0)
+
+#define V4L2_LOG_WARN(...) \
+  do { \
+    if (v4l2_log_file) { \
+      fprintf(v4l2_log_file, "libv4l2: warning " __VA_ARGS__); \
+      fflush(v4l2_log_file); \
+    } else \
+      fprintf(stderr, "libv4l2: warning " __VA_ARGS__); \
+  } while(0)
+
+#define V4L2_LOG(...) \
+  do { \
+    if (v4l2_log_file) { \
+      fprintf(v4l2_log_file, "libv4l2: " __VA_ARGS__); \
+      fflush(v4l2_log_file); \
+    } \
+  } while(0)
+
+#define MIN(a,b) (((a)<(b))?(a):(b))
+
+struct v4l2_dev_info {
+  int fd;
+  int flags;
+  int open_count;
+  /* actually format of the cam */
+  struct v4l2_format src_fmt;
+  /* fmt as seen by the application (iow after conversion) */
+  struct v4l2_format dest_fmt;
+  pthread_mutex_t stream_lock;
+  unsigned int no_frames;
+  unsigned int nreadbuffers;
+  struct v4lconvert_data *convert;
+  unsigned char *convert_mmap_buf;
+  /* Frame bookkeeping is only done when in read or mmap-conversion mode */
+  unsigned char *frame_pointers[V4L2_MAX_NO_FRAMES];
+  int frame_sizes[V4L2_MAX_NO_FRAMES];
+  int frame_queued; /* 1 status bit per frame */
+  /* mapping tracking of our fake (converting mmap) frame buffers */
+  unsigned char frame_map_count[V4L2_MAX_NO_FRAMES];
+};
+
+/* From log.c */
+void v4l2_log_ioctl(unsigned long int request, void *arg, int result);
+
+#endif
diff --git a/v4l2-apps/libv4l/libv4l2/libv4l2.c b/v4l2-apps/libv4l/libv4l2/libv4l2.c
new file mode 100644
index 000000000..b4a10afac
--- /dev/null
+++ b/v4l2-apps/libv4l/libv4l2/libv4l2.c
@@ -0,0 +1,1145 @@
+/*
+#             (C) 2008 Hans de Goede <j.w.r.degoede@hhs.nl>
+
+# 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
+*/
+
+/* MAKING CHANGES TO THIS FILE??   READ THIS FIRST!!!
+
+   This file implements libv4l2, which offers v4l2_ prefixed versions of
+   open/close/etc. The API is 100% the same as directly opening /dev/videoX
+   using regular open/close/etc, the big difference is that format conversion
+   is done if necessary when capturing. That is if you (try to) set a capture
+   format which is not supported by the cam, but is supported by libv4lconvert,
+   then the try_fmt / set_fmt will succeed as if the cam supports the format
+   and on dqbuf / read the data will be converted for you and returned in
+   the request format.
+
+   Important note to people making changes to this file: All functions
+   (v4l2_close, v4l2_ioctl, etc.) are designed to function as their regular
+   counterpart when they get passed a fd that is not "registered" by libv4l2,
+   there are 2 reasons for this:
+   1) This allows us to get completely out of the way when dealing with non
+      capture devices.
+   2) libv4l2 is the base of the v4l2convert.so wrapper lib, which is a .so
+      which can be LD_PRELOAD-ed and the overrules the libc's open/close/etc,
+      and when opening /dev/videoX or /dev/v4l/ calls v4l2_open.  Because we
+      behave as the regular counterpart when the fd is not known (instead of say
+      throwing an error), v4l2convert.so can simply call the v4l2_ prefixed
+      function for all wrapped functions (except for v4l2_open which will fail
+      when not called on a v4l2 device). This way the wrapper does not have to
+      keep track of which fd's are being handled by libv4l2, as libv4l2 already
+      keeps track of this itself.
+
+      This also means that libv4l2 may not use any of the regular functions
+      it mimics, as for example open could be a symbol in v4l2convert.so, which
+      in turn will call v4l2_open, so therefor v4l2_open (for example) may not
+      use the regular open()!
+
+   Another important note: libv4l2 does conversion for capture usage only, if
+   any calls are made which are passed a v4l2_buffer or v4l2_format with a
+   v4l2_buf_type which is different from V4L2_BUF_TYPE_VIDEO_CAPTURE, then
+   the v4l2_ methods behave exactly the same as their regular counterparts.
+   When modifications are made, one should be carefull that this behavior is
+   preserved.
+*/
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <syscall.h>
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include "libv4l2.h"
+#include "libv4l2-priv.h"
+
+/* Note these flags are stored together with the flags passed to v4l2_fd_open()
+   in v4l2_dev_info's flags member, so care should be taken that the do not
+   use the same bits! */
+#define V4L2_STREAMON			0x0100
+#define V4L2_BUFFERS_REQUESTED_BY_READ	0x0200
+#define V4L2_STREAM_CONTROLLED_BY_READ	0x0400
+#define V4L2_SUPPORTS_READ		0x0800
+
+#define V4L2_MMAP_OFFSET_MAGIC      0xABCDEF00u
+
+static pthread_mutex_t v4l2_open_mutex = PTHREAD_MUTEX_INITIALIZER;
+static struct v4l2_dev_info devices[V4L2_MAX_DEVICES] = { { .fd = -1 },
+  { .fd = -1 }, { .fd = -1 }, { .fd = -1 }, { .fd = -1 }, { .fd = -1 },
+  { .fd = -1 }, { .fd = -1 }, { .fd = -1 }, { .fd = -1 }, { .fd = -1 },
+  { .fd = -1 }, { .fd = -1 }, { .fd = -1 }, { .fd = -1 }, { .fd = -1 }};
+static int devices_used = 0;
+
+
+static int v4l2_request_read_buffers(int index)
+{
+  int result;
+  struct v4l2_requestbuffers req;
+
+  /* Note we re-request the buffers if they are already requested as the format
+     and thus the needed buffersize may have changed. */
+  req.count = (devices[index].no_frames)? devices[index].no_frames:
+					  devices[index].nreadbuffers;
+  req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+  req.memory = V4L2_MEMORY_MMAP;
+  if ((result = syscall(SYS_ioctl, devices[index].fd, VIDIOC_REQBUFS, &req)) < 0){
+    int saved_err = errno;
+    V4L2_LOG_ERR("requesting %u buffers: %s\n", req.count, strerror(errno));
+    errno = saved_err;
+    return result;
+  }
+
+  if (!devices[index].no_frames && req.count)
+    devices[index].flags |= V4L2_BUFFERS_REQUESTED_BY_READ;
+
+  devices[index].no_frames = MIN(req.count, V4L2_MAX_NO_FRAMES);
+  return 0;
+}
+
+static void v4l2_unrequest_read_buffers(int index)
+{
+  struct v4l2_requestbuffers req;
+
+  if (!(devices[index].flags & V4L2_BUFFERS_REQUESTED_BY_READ) ||
+      devices[index].no_frames == 0)
+    return;
+
+  /* (Un)Request buffers, note not all driver support this, and those
+     who do not support it don't need it. */
+  req.count = 0;
+  req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+  req.memory = V4L2_MEMORY_MMAP;
+  if(syscall(SYS_ioctl, devices[index].fd, VIDIOC_REQBUFS, &req) < 0)
+    return;
+
+  devices[index].no_frames = MIN(req.count, V4L2_MAX_NO_FRAMES);
+  if (devices[index].no_frames == 0)
+    devices[index].flags &= ~V4L2_BUFFERS_REQUESTED_BY_READ;
+}
+
+static int v4l2_map_buffers(int index)
+{
+  int result = 0;
+  unsigned int i;
+  struct v4l2_buffer buf;
+
+  for (i = 0; i < devices[index].no_frames; i++) {
+    if (devices[index].frame_pointers[i] != MAP_FAILED)
+      continue;
+
+    buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+    buf.memory = V4L2_MEMORY_MMAP;
+    buf.index = i;
+    result = syscall(SYS_ioctl, devices[index].fd, VIDIOC_QUERYBUF, &buf);
+    if (result) {
+      int saved_err = errno;
+      V4L2_LOG_ERR("querying buffer %u: %s\n", i, strerror(errno));
+      errno = saved_err;
+      break;
+    }
+
+    devices[index].frame_pointers[i] = (void *)syscall(SYS_mmap2, NULL,
+      (size_t)buf.length, PROT_READ|PROT_WRITE, MAP_SHARED, devices[index].fd,
+      (__off_t)(buf.m.offset >> MMAP2_PAGE_SHIFT));
+    if (devices[index].frame_pointers[i] == MAP_FAILED) {
+      int saved_err = errno;
+      V4L2_LOG_ERR("mmapping buffer %u: %s\n", i, strerror(errno));
+      errno = saved_err;
+      result = -1;
+      break;
+    }
+    V4L2_LOG("mapped buffer %u at %p\n", i,
+      devices[index].frame_pointers[i]);
+
+    devices[index].frame_sizes[i] = buf.length;
+  }
+
+  return result;
+}
+
+static void v4l2_unmap_buffers(int index)
+{
+  unsigned int i;
+
+  /* unmap the buffers */
+  for (i = 0; i < devices[index].no_frames; i++) {
+    if (devices[index].frame_pointers[i] != MAP_FAILED) {
+      syscall(SYS_munmap, devices[index].frame_pointers[i],
+	      devices[index].frame_sizes[i]);
+      devices[index].frame_pointers[i] = MAP_FAILED;
+      V4L2_LOG("unmapped buffer %u\n", i);
+    }
+  }
+}
+
+static int v4l2_streamon(int index)
+{
+  int result;
+  enum v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+
+  if (!(devices[index].flags & V4L2_STREAMON)) {
+    if ((result = syscall(SYS_ioctl, devices[index].fd, VIDIOC_STREAMON,
+			  &type))) {
+      int saved_err = errno;
+      V4L2_LOG_ERR("turning on stream: %s\n", strerror(errno));
+      errno = saved_err;
+      return result;
+    }
+    devices[index].flags |= V4L2_STREAMON;
+  }
+
+  return 0;
+}
+
+static int v4l2_streamoff(int index)
+{
+  int result;
+  enum v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+
+  if (devices[index].flags & V4L2_STREAMON) {
+    if ((result = syscall(SYS_ioctl, devices[index].fd, VIDIOC_STREAMOFF,
+			  &type))) {
+      int saved_err = errno;
+      V4L2_LOG_ERR("turning off stream: %s\n", strerror(errno));
+      errno = saved_err;
+      return result;
+    }
+    devices[index].flags &= ~V4L2_STREAMON;
+
+    /* Stream off also unqueues all our buffers! */
+    devices[index].frame_queued = 0;
+  }
+
+  return 0;
+}
+
+static int v4l2_queue_read_buffer(int index, int buffer_index)
+{
+  int result;
+  struct v4l2_buffer buf;
+
+  if (devices[index].frame_queued & (1 << buffer_index))
+    return 0;
+
+  memset(&buf, 0, sizeof(buf));
+  buf.type   = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+  buf.memory = V4L2_MEMORY_MMAP;
+  buf.index  = buffer_index;
+  if ((result = syscall(SYS_ioctl, devices[index].fd, VIDIOC_QBUF, &buf))) {
+    int saved_err = errno;
+    V4L2_LOG_ERR("queuing buf %d: %s\n", buffer_index, strerror(errno));
+    errno = saved_err;
+    return result;
+  }
+
+  devices[index].frame_queued |= 1 << buffer_index;
+  return 0;
+}
+
+static int v4l2_dequeue_and_convert(int index, struct v4l2_buffer *buf,
+  unsigned char *dest, int dest_size)
+{
+  const int max_tries = 10;
+  int result, tries = max_tries;
+
+  /* Make sure we have the real v4l2 buffers mapped */
+  if ((result = v4l2_map_buffers(index)))
+    return result;
+
+  do {
+    if ((result = syscall(SYS_ioctl, devices[index].fd, VIDIOC_DQBUF, buf))) {
+      int saved_err = errno;
+      V4L2_LOG_ERR("dequeuing buf: %s\n", strerror(errno));
+      errno = saved_err;
+      return result;
+    }
+
+    devices[index].frame_queued &= ~(1 << buf->index);
+
+    result = v4lconvert_convert(devices[index].convert,
+	   &devices[index].src_fmt, &devices[index].dest_fmt,
+	   devices[index].frame_pointers[buf->index],
+	   buf->bytesused, dest ? dest : (devices[index].convert_mmap_buf +
+	     buf->index * V4L2_FRAME_BUF_SIZE), dest_size);
+
+    if (result < 0) {
+      int saved_err = errno;
+
+      if(errno == EAGAIN)
+	V4L2_LOG("warning error while converting frame data: %s\n",
+	  v4lconvert_get_error_message(devices[index].convert));
+      else
+	V4L2_LOG_ERR("converting / decoding frame data: %s\n",
+	  v4lconvert_get_error_message(devices[index].convert));
+
+      v4l2_queue_read_buffer(index, buf->index);
+      errno = saved_err;
+    }
+    tries--;
+  } while (result < 0 && errno == EAGAIN && tries);
+
+  if (result < 0 && errno == EAGAIN) {
+    V4L2_LOG_ERR("got %d consecutive frame decode errors, last error: %s\n",
+      max_tries, v4lconvert_get_error_message(devices[index].convert));
+  }
+
+  return result;
+}
+
+static int v4l2_queue_read_buffers(int index)
+{
+  unsigned int i;
+  int last_error = EIO, queued = 0;
+
+  for (i = 0; i < devices[index].no_frames; i++) {
+    /* Don't queue unmapped buffers (should never happen) */
+    if (devices[index].frame_pointers[i] != MAP_FAILED) {
+      if (v4l2_queue_read_buffer(index, i)) {
+	last_error = errno;
+	continue;
+      }
+      queued++;
+    }
+  }
+
+  if (!queued) {
+    errno = last_error;
+    return -1;
+  }
+  return 0;
+}
+
+static int v4l2_activate_read_stream(int index)
+{
+  int result;
+
+  if ((result = v4l2_request_read_buffers(index)))
+    return result;
+
+  if ((result = v4l2_map_buffers(index)))
+    return result;
+
+  if ((result = v4l2_queue_read_buffers(index)))
+    return result;
+
+  devices[index].flags |= V4L2_STREAM_CONTROLLED_BY_READ;
+
+  return result = v4l2_streamon(index);
+}
+
+static int v4l2_deactivate_read_stream(int index)
+{
+  int result;
+
+  if ((result = v4l2_streamoff(index)))
+    return result;
+
+  /* No need to unqueue our buffers, streamoff does that for us */
+
+  v4l2_unmap_buffers(index);
+
+  v4l2_unrequest_read_buffers(index);
+
+  devices[index].flags &= ~V4L2_STREAM_CONTROLLED_BY_READ;
+
+  return 0;
+}
+
+static int v4l2_buffers_mapped(int index)
+{
+  unsigned int i;
+
+  if (devices[index].src_fmt.fmt.pix.pixelformat ==
+      devices[index].dest_fmt.fmt.pix.pixelformat) {
+    /* Normal (no conversion) mode */
+    struct v4l2_buffer buf;
+
+    for (i = 0; i < devices[index].no_frames; i++) {
+      buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+      buf.memory = V4L2_MEMORY_MMAP;
+      buf.index = i;
+      if (syscall(SYS_ioctl, devices[index].fd, VIDIOC_QUERYBUF, &buf)) {
+	int saved_err = errno;
+	V4L2_LOG_ERR("querying buffer %u: %s\n", i, strerror(errno));
+	errno = saved_err;
+	break;
+      }
+      if (buf.flags & V4L2_BUF_FLAG_MAPPED)
+	break;
+    }
+  } else {
+    /* Conversion mode */
+    for (i = 0; i < devices[index].no_frames; i++)
+      if (devices[index].frame_map_count[i])
+	break;
+  }
+
+  if (i != devices[index].no_frames)
+    V4L2_LOG("v4l2_buffers_mapped(): buffers still mapped\n");
+
+  return i != devices[index].no_frames;
+}
+
+
+int v4l2_open (const char *file, int oflag, ...)
+{
+  int fd;
+
+  /* original open code */
+  if (oflag & O_CREAT)
+  {
+    va_list ap;
+    mode_t mode;
+
+    va_start (ap, oflag);
+    mode = va_arg (ap, mode_t);
+
+    fd = syscall(SYS_open, file, oflag, mode);
+
+    va_end(ap);
+  }
+  else
+    fd = syscall(SYS_open, file, oflag);
+  /* end of original open code */
+
+  if (fd == -1)
+    return fd;
+
+  if (v4l2_fd_open(fd, 0) == -1) {
+    int saved_err = errno;
+    syscall(SYS_close, fd);
+    errno = saved_err;
+    return -1;
+  }
+
+  return fd;
+}
+
+int v4l2_fd_open(int fd, int v4l2_flags)
+{
+  int i, index;
+  char *lfname;
+  struct v4l2_capability cap;
+  struct v4l2_format fmt;
+  struct v4lconvert_data *convert;
+
+  /* If no log file was set by the app, see if one was specified through the
+     environment */
+  if (!v4l2_log_file && (lfname = getenv("LIBV4L2_LOG_FILENAME")))
+    v4l2_log_file = fopen(lfname, "w");
+
+  /* check that this is an v4l2 device */
+  if (syscall(SYS_ioctl, fd, VIDIOC_QUERYCAP, &cap)) {
+    int saved_err = errno;
+    V4L2_LOG_ERR("getting capabilities: %s\n", strerror(errno));
+    errno = saved_err;
+    return -1;
+  }
+
+  /* we only add functionality for video capture devices, and we do not
+     handle devices which don't do mmap */
+  if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE) ||
+      !(cap.capabilities & V4L2_CAP_STREAMING))
+    return fd;
+
+  /* Get current cam format */
+  fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+  if (syscall(SYS_ioctl, fd, VIDIOC_G_FMT, &fmt)) {
+    int saved_err = errno;
+    V4L2_LOG_ERR("getting pixformat: %s\n", strerror(errno));
+    errno = saved_err;
+    return -1;
+  }
+
+  /* init libv4lconvert */
+  if (!(convert = v4lconvert_create(fd)))
+    return -1;
+
+  /* So we have a v4l2 capture device, register it in our devices array */
+  pthread_mutex_lock(&v4l2_open_mutex);
+  for (index = 0; index < V4L2_MAX_DEVICES; index++)
+    if(devices[index].fd == -1) {
+      devices[index].fd = fd;
+      break;
+    }
+  pthread_mutex_unlock(&v4l2_open_mutex);
+
+  if (index == V4L2_MAX_DEVICES) {
+    V4L2_LOG_ERR("attempting to open more then %d video devices\n",
+      V4L2_MAX_DEVICES);
+    errno = EBUSY;
+    return -1;
+  }
+
+  devices[index].flags = v4l2_flags;
+  if (cap.capabilities & V4L2_CAP_READWRITE)
+    devices[index].flags |= V4L2_SUPPORTS_READ;
+  devices[index].open_count = 1;
+  devices[index].src_fmt = fmt;
+  devices[index].dest_fmt = fmt;
+
+  pthread_mutex_init(&devices[index].stream_lock, NULL);
+
+  devices[index].no_frames = 0;
+  devices[index].nreadbuffers = V4L2_DEFAULT_NREADBUFFERS;
+  devices[index].convert = convert;
+  devices[index].convert_mmap_buf = MAP_FAILED;
+  for (i = 0; i < V4L2_MAX_NO_FRAMES; i++) {
+    devices[index].frame_pointers[i] = MAP_FAILED;
+    devices[index].frame_map_count[i] = 0;
+  }
+  devices[index].frame_queued = 0;
+
+  if (index >= devices_used)
+    devices_used = index + 1;
+
+  V4L2_LOG("open: %d\n", fd);
+
+  return fd;
+}
+
+/* Is this an fd for which we are emulating v4l1 ? */
+static int v4l2_get_index(int fd)
+{
+  int index;
+
+  /* We never handle fd -1 */
+  if (fd == -1)
+    return -1;
+
+  for (index = 0; index < devices_used; index++)
+    if (devices[index].fd == fd)
+      break;
+
+  if (index == devices_used)
+    return -1;
+
+  return index;
+}
+
+
+int v4l2_close(int fd)
+{
+  int index, result;
+
+  if ((index = v4l2_get_index(fd)) == -1)
+    return syscall(SYS_close, fd);
+
+  /* Abuse stream_lock to stop 2 closes from racing and trying to free the
+     resources twice */
+  pthread_mutex_lock(&devices[index].stream_lock);
+  devices[index].open_count--;
+  result = devices[index].open_count != 0;
+  pthread_mutex_unlock(&devices[index].stream_lock);
+
+  if (result)
+    return 0;
+
+  /* Free resources */
+  v4l2_unmap_buffers(index);
+  v4lconvert_destroy(devices[index].convert);
+  if (devices[index].convert_mmap_buf != MAP_FAILED) {
+    if (v4l2_buffers_mapped(index))
+      V4L2_LOG_WARN("v4l2 mmap buffers still mapped on close()\n");
+    else
+      syscall(SYS_munmap, devices[index].convert_mmap_buf,
+	      devices[index].no_frames * V4L2_FRAME_BUF_SIZE);
+    devices[index].convert_mmap_buf = MAP_FAILED;
+  }
+
+  /* Remove the fd from our list of managed fds before closing it, because as
+     soon as we've done the actual close the fd maybe returned by an open in
+     another thread and we don't want to intercept calls to this new fd. */
+  devices[index].fd = -1;
+
+  /* Since we've marked the fd as no longer used, and freed the resources,
+     redo the close in case it was interrupted */
+  do {
+    result = syscall(SYS_close, fd);
+  } while (result == -1 && errno == EINTR);
+
+  V4L2_LOG("close: %d\n", fd);
+
+  return result;
+}
+
+int v4l2_dup(int fd)
+{
+  int index;
+
+  if ((index = v4l2_get_index(fd)) == -1)
+    return syscall(SYS_dup, fd);
+
+  devices[index].open_count++;
+
+  return fd;
+}
+
+static int v4l2_check_buffer_change_ok(int index)
+{
+  v4l2_unmap_buffers(index);
+
+  /* Check if the app itself still is using the stream */
+  if (v4l2_buffers_mapped(index) ||
+       (!(devices[index].flags & V4L2_STREAM_CONTROLLED_BY_READ) &&
+	 ((devices[index].flags & V4L2_STREAMON) ||
+	   devices[index].frame_queued))) {
+    V4L2_LOG("v4l2_check_buffer_change_ok(): stream busy\n");
+    errno = EBUSY;
+    return -1;
+  }
+
+  /* We may change from convert to non conversion mode and
+     v4l2_unrequest_read_buffers may change the no_frames, so free the
+     convert mmap buffer */
+  syscall(SYS_munmap, devices[index].convert_mmap_buf,
+    devices[index].no_frames * V4L2_FRAME_BUF_SIZE);
+  devices[index].convert_mmap_buf = MAP_FAILED;
+
+  if (devices[index].flags & V4L2_STREAM_CONTROLLED_BY_READ) {
+    V4L2_LOG("deactivating read-stream for settings change\n");
+    return v4l2_deactivate_read_stream(index);
+  }
+
+  return 0;
+}
+
+int v4l2_ioctl (int fd, unsigned long int request, ...)
+{
+  void *arg;
+  va_list ap;
+  int result, converting, index, saved_err;
+  int is_capture_request = 0, stream_needs_locking = 0;
+
+  va_start (ap, request);
+  arg = va_arg (ap, void *);
+  va_end (ap);
+
+  if ((index = v4l2_get_index(fd)) == -1)
+    return syscall(SYS_ioctl, fd, request, arg);
+
+  /* Appearantly the kernel and / or glibc ignore the 32 most significant bits
+     when long = 64 bits, and some applications pass an int holding the req to
+     ioctl, causing it to get sign extended, depending upon this behavior */
+  request = (unsigned int)request;
+
+  /* Is this a capture request and do we need to take the stream lock? */
+  switch (request) {
+    case VIDIOC_QUERYCAP:
+      is_capture_request = 1;
+      break;
+    case VIDIOC_ENUM_FMT:
+      if (((struct v4l2_fmtdesc *)arg)->type == V4L2_BUF_TYPE_VIDEO_CAPTURE &&
+	  (devices[index].flags & V4L2_ENABLE_ENUM_FMT_EMULATION))
+	is_capture_request = 1;
+      break;
+    case VIDIOC_ENUM_FRAMESIZES:
+    case VIDIOC_ENUM_FRAMEINTERVALS:
+      if (devices[index].flags & V4L2_ENABLE_ENUM_FMT_EMULATION)
+	is_capture_request = 1;
+      break;
+    case VIDIOC_TRY_FMT:
+      if (((struct v4l2_format *)arg)->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
+	is_capture_request = 1;
+      break;
+    case VIDIOC_S_FMT:
+    case VIDIOC_G_FMT:
+      if (((struct v4l2_format *)arg)->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+	is_capture_request = 1;
+	stream_needs_locking = 1;
+      }
+      break;
+    case VIDIOC_REQBUFS:
+      if (((struct v4l2_requestbuffers *)arg)->type ==
+	  V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+	is_capture_request = 1;
+	stream_needs_locking = 1;
+      }
+      break;
+    case VIDIOC_QUERYBUF:
+    case VIDIOC_QBUF:
+    case VIDIOC_DQBUF:
+      if (((struct v4l2_buffer *)arg)->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+	is_capture_request = 1;
+	stream_needs_locking = 1;
+      }
+      break;
+    case VIDIOC_STREAMON:
+    case VIDIOC_STREAMOFF:
+      if (*((enum v4l2_buf_type *)arg) == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+	is_capture_request = 1;
+	stream_needs_locking = 1;
+      }
+  }
+
+  if (!is_capture_request) {
+    result = syscall(SYS_ioctl, fd, request, arg);
+    saved_err = errno;
+    v4l2_log_ioctl(request, arg, result);
+    errno = saved_err;
+    return result;
+  }
+
+
+  if (stream_needs_locking)
+    pthread_mutex_lock(&devices[index].stream_lock);
+
+  converting = v4lconvert_needs_conversion(devices[index].convert,
+			 &devices[index].src_fmt, &devices[index].dest_fmt);
+
+  switch (request) {
+    case VIDIOC_QUERYCAP:
+      {
+	struct v4l2_capability *cap = arg;
+
+	result = syscall(SYS_ioctl, devices[index].fd, VIDIOC_QUERYCAP, cap);
+	if (result == 0)
+	  /* We always support read() as we fake it using mmap mode */
+	  cap->capabilities |= V4L2_CAP_READWRITE;
+      }
+      break;
+
+    case VIDIOC_ENUM_FMT:
+      result = v4lconvert_enum_fmt(devices[index].convert, arg);
+      break;
+
+    case VIDIOC_ENUM_FRAMESIZES:
+      result = v4lconvert_enum_framesizes(devices[index].convert, arg);
+      break;
+
+    case VIDIOC_ENUM_FRAMEINTERVALS:
+      result = v4lconvert_enum_frameintervals(devices[index].convert, arg);
+      break;
+
+    case VIDIOC_TRY_FMT:
+      result = v4lconvert_try_format(devices[index].convert, arg, NULL);
+      break;
+
+    case VIDIOC_S_FMT:
+      {
+	struct v4l2_format src_fmt, *dest_fmt = arg;
+
+	if (!memcmp(&devices[index].dest_fmt, dest_fmt, sizeof(*dest_fmt))) {
+	  result = 0;
+	  break;
+	}
+
+	if (devices[index].flags & V4L2_DISABLE_CONVERSION) {
+	  result = syscall(SYS_ioctl, devices[index].fd, VIDIOC_TRY_FMT,
+			   dest_fmt);
+	  src_fmt = *dest_fmt;
+	} else {
+	  result = v4lconvert_try_format(devices[index].convert, dest_fmt,
+					 &src_fmt);
+	}
+
+	if (result)
+	  break;
+
+	if (src_fmt.fmt.pix.pixelformat != dest_fmt->fmt.pix.pixelformat &&
+	    v4l2_log_file) {
+	  int pixfmt = src_fmt.fmt.pix.pixelformat;
+
+	  fprintf(v4l2_log_file, "VIDIOC_S_FMT converting from: %c%c%c%c\n",
+	    pixfmt & 0xff,
+	    (pixfmt >> 8) & 0xff,
+	    (pixfmt >> 16) & 0xff,
+	    pixfmt >> 24);
+	}
+
+	/* Maybe after try format has adjusted width/height etc, to whats
+	   available nothing has changed (on the cam side) ? */
+	if (!memcmp(&devices[index].src_fmt, &src_fmt, sizeof(src_fmt))) {
+	  devices[index].dest_fmt = *dest_fmt;
+	  result = 0;
+	  break;
+	}
+
+	if ((result = v4l2_check_buffer_change_ok(index)))
+	  break;
+
+	result = syscall(SYS_ioctl, devices[index].fd, VIDIOC_S_FMT, &src_fmt);
+	if (result) {
+	  saved_err = errno;
+	  V4L2_LOG_ERR("setting pixformat: %s\n", strerror(errno));
+	  /* Report to the app dest_fmt has not changed */
+	  *dest_fmt = devices[index].dest_fmt;
+	  errno = saved_err;
+	  break;
+	}
+
+	devices[index].src_fmt = src_fmt;
+	devices[index].dest_fmt = *dest_fmt;
+      }
+      break;
+
+    case VIDIOC_G_FMT:
+      {
+	struct v4l2_format* fmt = arg;
+
+	*fmt = devices[index].dest_fmt;
+	result = 0;
+      }
+      break;
+
+    case VIDIOC_REQBUFS:
+      {
+	struct v4l2_requestbuffers *req = arg;
+
+	/* IMPROVEME (maybe?) add support for userptr's? */
+	if (req->memory != V4L2_MEMORY_MMAP) {
+	  errno = EINVAL;
+	  result = -1;
+	  break;
+	}
+
+	if ((result = v4l2_check_buffer_change_ok(index)))
+	  break;
+
+	/* No more buffers then we can manage please */
+	if (req->count > V4L2_MAX_NO_FRAMES)
+	  req->count = V4L2_MAX_NO_FRAMES;
+
+	result = syscall(SYS_ioctl, devices[index].fd, VIDIOC_REQBUFS, req);
+	if (result < 0)
+	  break;
+	result = 0; /* some drivers return the number of buffers on success */
+
+	devices[index].no_frames = MIN(req->count, V4L2_MAX_NO_FRAMES);
+	devices[index].flags &= ~V4L2_BUFFERS_REQUESTED_BY_READ;
+      }
+      break;
+
+    case VIDIOC_QUERYBUF:
+      {
+	struct v4l2_buffer *buf = arg;
+
+	if (devices[index].flags & V4L2_STREAM_CONTROLLED_BY_READ)
+	  if ((result = v4l2_deactivate_read_stream(index)))
+	    break;
+
+	/* Do a real query even when converting to let the driver fill in
+	   things like buf->field */
+	result = syscall(SYS_ioctl, devices[index].fd, VIDIOC_QUERYBUF, buf);
+	if (result || !converting)
+	  break;
+
+	buf->m.offset = V4L2_MMAP_OFFSET_MAGIC | buf->index;
+	buf->length = V4L2_FRAME_BUF_SIZE;
+	if (devices[index].frame_map_count[buf->index])
+	  buf->flags |= V4L2_BUF_FLAG_MAPPED;
+	else
+	  buf->flags &= ~V4L2_BUF_FLAG_MAPPED;
+      }
+      break;
+
+    case VIDIOC_QBUF:
+      if (devices[index].flags & V4L2_STREAM_CONTROLLED_BY_READ)
+	if ((result = v4l2_deactivate_read_stream(index)))
+	  break;
+
+      /* With some drivers the buffers must be mapped before queuing */
+      if (converting)
+	if ((result = v4l2_map_buffers(index)))
+	  break;
+
+      result = syscall(SYS_ioctl, devices[index].fd, VIDIOC_QBUF, arg);
+      break;
+
+    case VIDIOC_DQBUF:
+      {
+	struct v4l2_buffer *buf = arg;
+
+	if (devices[index].flags & V4L2_STREAM_CONTROLLED_BY_READ)
+	  if ((result = v4l2_deactivate_read_stream(index)))
+	    break;
+
+	if (!converting) {
+	  result = syscall(SYS_ioctl, devices[index].fd, VIDIOC_DQBUF, buf);
+	  if (result) {
+	    int saved_err = errno;
+	    V4L2_LOG_ERR("dequeuing buf: %s\n", strerror(errno));
+	    errno = saved_err;
+	  }
+	  break;
+	}
+
+	/* An application can do a DQBUF before mmap-ing in the buffer,
+	   but we need the buffer _now_ to write our converted data
+	   to it! */
+	if (devices[index].convert_mmap_buf == MAP_FAILED) {
+	  devices[index].convert_mmap_buf = (void *)syscall(SYS_mmap2,
+						   (size_t)(
+						     devices[index].no_frames *
+						     V4L2_FRAME_BUF_SIZE),
+						   PROT_READ|PROT_WRITE,
+						   MAP_ANONYMOUS|MAP_PRIVATE,
+						   -1, 0);
+	  if (devices[index].convert_mmap_buf == MAP_FAILED) {
+	    saved_err = errno;
+	    V4L2_LOG_ERR("allocating conversion buffer\n");
+	    errno = saved_err;
+	    result = -1;
+	    break;
+	  }
+	}
+
+	result = v4l2_dequeue_and_convert(index, buf, 0, V4L2_FRAME_BUF_SIZE);
+	if (result < 0)
+	  break;
+
+	buf->bytesused = result;
+	buf->m.offset = V4L2_MMAP_OFFSET_MAGIC | buf->index;
+	buf->length = V4L2_FRAME_BUF_SIZE;
+	if (devices[index].frame_map_count[buf->index])
+	  buf->flags |= V4L2_BUF_FLAG_MAPPED;
+	else
+	  buf->flags &= ~V4L2_BUF_FLAG_MAPPED;
+
+	result = 0;
+      }
+      break;
+
+    case VIDIOC_STREAMON:
+    case VIDIOC_STREAMOFF:
+      if (devices[index].flags & V4L2_STREAM_CONTROLLED_BY_READ)
+	if ((result = v4l2_deactivate_read_stream(index)))
+	  break;
+
+      if (request == VIDIOC_STREAMON)
+	result = v4l2_streamon(index);
+      else
+	result = v4l2_streamoff(index);
+      break;
+
+    default:
+      result = syscall(SYS_ioctl, fd, request, arg);
+  }
+
+  if (stream_needs_locking)
+    pthread_mutex_unlock(&devices[index].stream_lock);
+
+  saved_err = errno;
+  v4l2_log_ioctl(request, arg, result);
+  errno = saved_err;
+
+  return result;
+}
+
+
+ssize_t v4l2_read (int fd, void* dest, size_t n)
+{
+  ssize_t result;
+  int index;
+  struct v4l2_buffer buf;
+
+  if ((index = v4l2_get_index(fd)) == -1)
+    return syscall(SYS_read, fd, dest, n);
+
+  pthread_mutex_lock(&devices[index].stream_lock);
+
+  /* When not converting and the device supports read let the kernel handle
+     it */
+  if ((devices[index].flags & V4L2_SUPPORTS_READ) &&
+      !v4lconvert_needs_conversion(devices[index].convert,
+		   &devices[index].src_fmt, &devices[index].dest_fmt)) {
+    result = syscall(SYS_read, fd, dest, n);
+    goto leave;
+  }
+
+  if (!(devices[index].flags & V4L2_STREAM_CONTROLLED_BY_READ)) {
+    if ((devices[index].flags & V4L2_STREAMON) ||
+	devices[index].frame_queued) {
+      errno = EBUSY;
+      result = -1;
+      goto leave;
+    }
+    if ((result = v4l2_activate_read_stream(index)))
+      goto leave;
+  }
+
+  buf.type   = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+  buf.memory = V4L2_MEMORY_MMAP;
+  result = v4l2_dequeue_and_convert(index, &buf, dest, n);
+
+  if (result >= 0)
+    v4l2_queue_read_buffer(index, buf.index);
+
+leave:
+  pthread_mutex_unlock(&devices[index].stream_lock);
+
+  return result;
+}
+
+void *v4l2_mmap(void *start, size_t length, int prot, int flags, int fd,
+  __off64_t offset)
+{
+  int index;
+  unsigned int buffer_index;
+  void *result;
+
+  if ((index = v4l2_get_index(fd)) == -1 ||
+      /* Check if the mmap data matches our answer to QUERY_BUF, if it doesn't
+	 let the kernel handle it (to allow for mmap based non capture use) */
+      start || length != V4L2_FRAME_BUF_SIZE ||
+      ((unsigned int)offset & ~0xFFu) != V4L2_MMAP_OFFSET_MAGIC) {
+    if (index != -1)
+      V4L2_LOG("Passing mmap(%p, %d, ..., %x, through to the driver\n",
+	start, (int)length, (int)offset);
+
+    if (offset & ((1 << MMAP2_PAGE_SHIFT) - 1)) {
+      errno = EINVAL;
+      return MAP_FAILED;
+    }
+
+    return (void *)syscall(SYS_mmap2, start, length, prot, flags, fd,
+			   (__off_t)(offset >> MMAP2_PAGE_SHIFT));
+  }
+
+  pthread_mutex_lock(&devices[index].stream_lock);
+
+  buffer_index = offset & 0xff;
+  if (buffer_index >= devices[index].no_frames ||
+      /* Got magic offset and not converting ?? */
+      !v4lconvert_needs_conversion(devices[index].convert,
+		   &devices[index].src_fmt, &devices[index].dest_fmt)) {
+    errno = EINVAL;
+    result = MAP_FAILED;
+    goto leave;
+  }
+
+  if (devices[index].convert_mmap_buf == MAP_FAILED) {
+    devices[index].convert_mmap_buf = (void *)syscall(SYS_mmap2, NULL,
+					     (size_t)(
+					       devices[index].no_frames *
+					       V4L2_FRAME_BUF_SIZE),
+					     PROT_READ|PROT_WRITE,
+					     MAP_ANONYMOUS|MAP_PRIVATE,
+					     -1, 0);
+    if (devices[index].convert_mmap_buf == MAP_FAILED) {
+      int saved_err = errno;
+      V4L2_LOG_ERR("allocating conversion buffer\n");
+      errno = saved_err;
+      result = MAP_FAILED;
+      goto leave;
+    }
+  }
+
+  devices[index].frame_map_count[buffer_index]++;
+
+  result = devices[index].convert_mmap_buf +
+    buffer_index * V4L2_FRAME_BUF_SIZE;
+
+  V4L2_LOG("Fake (conversion) mmap buf %u, seen by app at: %p\n",
+    buffer_index, result);
+
+leave:
+  pthread_mutex_unlock(&devices[index].stream_lock);
+
+  return result;
+}
+
+int v4l2_munmap(void *_start, size_t length)
+{
+  int index;
+  unsigned int buffer_index;
+  unsigned char *start = _start;
+
+  /* Is this memory ours? */
+  if (start != MAP_FAILED && length == V4L2_FRAME_BUF_SIZE) {
+    for (index = 0; index < devices_used; index++)
+      if (devices[index].fd != -1 &&
+	  devices[index].convert_mmap_buf != MAP_FAILED &&
+	  start >= devices[index].convert_mmap_buf &&
+	  (start - devices[index].convert_mmap_buf) % length == 0)
+	break;
+
+    if (index != devices_used) {
+      int unmapped = 0;
+
+      pthread_mutex_lock(&devices[index].stream_lock);
+
+      buffer_index = (start - devices[index].convert_mmap_buf) / length;
+
+      /* Redo our checks now that we have the lock, things may have changed */
+      if (devices[index].convert_mmap_buf != MAP_FAILED &&
+	  start >= devices[index].convert_mmap_buf &&
+	  (start - devices[index].convert_mmap_buf) % length == 0 &&
+	  buffer_index < devices[index].no_frames) {
+	if (devices[index].frame_map_count[buffer_index] > 0)
+	  devices[index].frame_map_count[buffer_index]--;
+	unmapped = 1;
+      }
+
+      pthread_mutex_unlock(&devices[index].stream_lock);
+
+      if (unmapped) {
+	V4L2_LOG("v4l2 fake buffer munmap %p, %d\n", start, (int)length);
+	return 0;
+      }
+    }
+  }
+
+  V4L2_LOG("v4l2 unknown munmap %p, %d\n", start, (int)length);
+
+  return syscall(SYS_munmap, _start, length);
+}
+
+/* Misc utility functions */
+int v4l2_set_control(int fd, int cid, int value)
+{
+  struct v4l2_queryctrl qctrl = { .id = cid };
+  struct v4l2_control ctrl = { .id = cid };
+  int result;
+
+  if ((result = syscall(SYS_ioctl, fd, VIDIOC_QUERYCTRL, &qctrl)))
+    return result;
+
+  if (!(qctrl.flags & V4L2_CTRL_FLAG_DISABLED) &&
+      !(qctrl.flags & V4L2_CTRL_FLAG_GRABBED)) {
+    if (qctrl.type == V4L2_CTRL_TYPE_BOOLEAN)
+      ctrl.value = value? 1:0;
+    else
+      ctrl.value = (value * (qctrl.maximum - qctrl.minimum) + 32767) / 65535 +
+		   qctrl.minimum;
+
+    result = syscall(SYS_ioctl, fd, VIDIOC_S_CTRL, &ctrl);
+  }
+
+  return result;
+}
+
+int v4l2_get_control(int fd, int cid)
+{
+  struct v4l2_queryctrl qctrl = { .id = cid };
+  struct v4l2_control ctrl = { .id = cid };
+
+  if (syscall(SYS_ioctl, fd, VIDIOC_QUERYCTRL, &qctrl))
+    return 0;
+
+  if (qctrl.flags & V4L2_CTRL_FLAG_DISABLED)
+    return 0;
+
+  if (syscall(SYS_ioctl, fd, VIDIOC_G_CTRL, &ctrl))
+    return 0;
+
+  return ((ctrl.value - qctrl.minimum) * 65535 +
+	  (qctrl.maximum - qctrl.minimum) / 2) /
+	 (qctrl.maximum - qctrl.minimum);
+}
diff --git a/v4l2-apps/libv4l/libv4l2/log.c b/v4l2-apps/libv4l/libv4l2/log.c
new file mode 100644
index 000000000..6237d55ec
--- /dev/null
+++ b/v4l2-apps/libv4l/libv4l2/log.c
@@ -0,0 +1,148 @@
+/*
+#             (C) 2008 Hans de Goede <j.w.r.degoede@hhs.nl>
+
+# 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 <stdio.h>
+#include <stdlib.h>
+#include <linux/ioctl.h>
+/* These headers are not needed by us, but by linux/videodev2.h,
+   which is broken on some systems and doesn't include them itself :( */
+#include <sys/time.h>
+#include <asm/types.h>
+/* end broken header workaround includes */
+#include <linux/videodev2.h>
+#include "libv4l2.h"
+#include "libv4l2-priv.h"
+
+#define ARRAY_SIZE(x) (sizeof(x)/sizeof((x)[0]))
+
+FILE *v4l2_log_file = NULL;
+
+static const char *v4l2_ioctls[] = {
+	/* start v4l2 ioctls */
+	[_IOC_NR(VIDIOC_QUERYCAP)]         = "VIDIOC_QUERYCAP",
+	[_IOC_NR(VIDIOC_RESERVED)]         = "VIDIOC_RESERVED",
+	[_IOC_NR(VIDIOC_ENUM_FMT)]         = "VIDIOC_ENUM_FMT",
+	[_IOC_NR(VIDIOC_G_FMT)]            = "VIDIOC_G_FMT",
+	[_IOC_NR(VIDIOC_S_FMT)]            = "VIDIOC_S_FMT",
+	[_IOC_NR(VIDIOC_REQBUFS)]          = "VIDIOC_REQBUFS",
+	[_IOC_NR(VIDIOC_QUERYBUF)]         = "VIDIOC_QUERYBUF",
+	[_IOC_NR(VIDIOC_G_FBUF)]           = "VIDIOC_G_FBUF",
+	[_IOC_NR(VIDIOC_S_FBUF)]           = "VIDIOC_S_FBUF",
+	[_IOC_NR(VIDIOC_OVERLAY)]          = "VIDIOC_OVERLAY",
+	[_IOC_NR(VIDIOC_QBUF)]             = "VIDIOC_QBUF",
+	[_IOC_NR(VIDIOC_DQBUF)]            = "VIDIOC_DQBUF",
+	[_IOC_NR(VIDIOC_STREAMON)]         = "VIDIOC_STREAMON",
+	[_IOC_NR(VIDIOC_STREAMOFF)]        = "VIDIOC_STREAMOFF",
+	[_IOC_NR(VIDIOC_G_PARM)]           = "VIDIOC_G_PARM",
+	[_IOC_NR(VIDIOC_S_PARM)]           = "VIDIOC_S_PARM",
+	[_IOC_NR(VIDIOC_G_STD)]            = "VIDIOC_G_STD",
+	[_IOC_NR(VIDIOC_S_STD)]            = "VIDIOC_S_STD",
+	[_IOC_NR(VIDIOC_ENUMSTD)]          = "VIDIOC_ENUMSTD",
+	[_IOC_NR(VIDIOC_ENUMINPUT)]        = "VIDIOC_ENUMINPUT",
+	[_IOC_NR(VIDIOC_G_CTRL)]           = "VIDIOC_G_CTRL",
+	[_IOC_NR(VIDIOC_S_CTRL)]           = "VIDIOC_S_CTRL",
+	[_IOC_NR(VIDIOC_G_TUNER)]          = "VIDIOC_G_TUNER",
+	[_IOC_NR(VIDIOC_S_TUNER)]          = "VIDIOC_S_TUNER",
+	[_IOC_NR(VIDIOC_G_AUDIO)]          = "VIDIOC_G_AUDIO",
+	[_IOC_NR(VIDIOC_S_AUDIO)]          = "VIDIOC_S_AUDIO",
+	[_IOC_NR(VIDIOC_QUERYCTRL)]        = "VIDIOC_QUERYCTRL",
+	[_IOC_NR(VIDIOC_QUERYMENU)]        = "VIDIOC_QUERYMENU",
+	[_IOC_NR(VIDIOC_G_INPUT)]          = "VIDIOC_G_INPUT",
+	[_IOC_NR(VIDIOC_S_INPUT)]          = "VIDIOC_S_INPUT",
+	[_IOC_NR(VIDIOC_G_OUTPUT)]         = "VIDIOC_G_OUTPUT",
+	[_IOC_NR(VIDIOC_S_OUTPUT)]         = "VIDIOC_S_OUTPUT",
+	[_IOC_NR(VIDIOC_ENUMOUTPUT)]       = "VIDIOC_ENUMOUTPUT",
+	[_IOC_NR(VIDIOC_G_AUDOUT)]         = "VIDIOC_G_AUDOUT",
+	[_IOC_NR(VIDIOC_S_AUDOUT)]         = "VIDIOC_S_AUDOUT",
+	[_IOC_NR(VIDIOC_G_MODULATOR)]      = "VIDIOC_G_MODULATOR",
+	[_IOC_NR(VIDIOC_S_MODULATOR)]      = "VIDIOC_S_MODULATOR",
+	[_IOC_NR(VIDIOC_G_FREQUENCY)]      = "VIDIOC_G_FREQUENCY",
+	[_IOC_NR(VIDIOC_S_FREQUENCY)]      = "VIDIOC_S_FREQUENCY",
+	[_IOC_NR(VIDIOC_CROPCAP)]          = "VIDIOC_CROPCAP",
+	[_IOC_NR(VIDIOC_G_CROP)]           = "VIDIOC_G_CROP",
+	[_IOC_NR(VIDIOC_S_CROP)]           = "VIDIOC_S_CROP",
+	[_IOC_NR(VIDIOC_G_JPEGCOMP)]       = "VIDIOC_G_JPEGCOMP",
+	[_IOC_NR(VIDIOC_S_JPEGCOMP)]       = "VIDIOC_S_JPEGCOMP",
+	[_IOC_NR(VIDIOC_QUERYSTD)]         = "VIDIOC_QUERYSTD",
+	[_IOC_NR(VIDIOC_TRY_FMT)]          = "VIDIOC_TRY_FMT",
+	[_IOC_NR(VIDIOC_ENUMAUDIO)]        = "VIDIOC_ENUMAUDIO",
+	[_IOC_NR(VIDIOC_ENUMAUDOUT)]       = "VIDIOC_ENUMAUDOUT",
+	[_IOC_NR(VIDIOC_G_PRIORITY)]       = "VIDIOC_G_PRIORITY",
+	[_IOC_NR(VIDIOC_S_PRIORITY)]       = "VIDIOC_S_PRIORITY",
+	[_IOC_NR(VIDIOC_G_SLICED_VBI_CAP)] = "VIDIOC_G_SLICED_VBI_CAP",
+	[_IOC_NR(VIDIOC_LOG_STATUS)]       = "VIDIOC_LOG_STATUS",
+	[_IOC_NR(VIDIOC_G_EXT_CTRLS)]      = "VIDIOC_G_EXT_CTRLS",
+	[_IOC_NR(VIDIOC_S_EXT_CTRLS)]      = "VIDIOC_S_EXT_CTRLS",
+	[_IOC_NR(VIDIOC_TRY_EXT_CTRLS)]    = "VIDIOC_TRY_EXT_CTRLS",
+};
+
+void v4l2_log_ioctl(unsigned long int request, void *arg, int result)
+{
+  const char *ioctl_str;
+  char buf[40];
+
+  if (!v4l2_log_file)
+    return;
+
+  if (_IOC_TYPE(request) == 'V' && _IOC_NR(request) < ARRAY_SIZE(v4l2_ioctls))
+    ioctl_str = v4l2_ioctls[_IOC_NR(request)];
+  else {
+    snprintf(buf, sizeof(buf), "unknown request: %c %d\n",
+      (int)_IOC_TYPE(request), (int)_IOC_NR(request));
+    ioctl_str = buf;
+  }
+
+  fprintf(v4l2_log_file, "request == %s\n", ioctl_str);
+
+  switch (request) {
+    case VIDIOC_G_FMT:
+    case VIDIOC_S_FMT:
+    case VIDIOC_TRY_FMT:
+      {
+	struct v4l2_format* fmt = arg;
+	int pixfmt = fmt->fmt.pix.pixelformat;
+
+	if (fmt->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+	  fprintf(v4l2_log_file, "  pixelformat: %c%c%c%c %ux%u\n",
+	    pixfmt & 0xff,
+	    (pixfmt >> 8) & 0xff,
+	    (pixfmt >> 16) & 0xff,
+	    pixfmt >> 24,
+	    fmt->fmt.pix.width,
+	    fmt->fmt.pix.height);
+	  fprintf(v4l2_log_file, "  field: %d bytesperline: %d imagesize%d\n",
+	    (int)fmt->fmt.pix.field, (int)fmt->fmt.pix.bytesperline,
+	    (int)fmt->fmt.pix.sizeimage);
+	  fprintf(v4l2_log_file, "  colorspace: %d, priv: %x\n",
+	    (int)fmt->fmt.pix.colorspace, (int)fmt->fmt.pix.priv);
+	}
+      }
+      break;
+    case VIDIOC_REQBUFS:
+      {
+	struct v4l2_requestbuffers *req = arg;
+
+	fprintf(v4l2_log_file, "  count: %u type: %d memory: %d\n",
+	  req->count, (int)req->type, (int)req->memory);
+      }
+      break;
+  }
+
+  fprintf(v4l2_log_file, "result == %d\n", result);
+  fflush(v4l2_log_file);
+}
diff --git a/v4l2-apps/libv4l/libv4l2/v4l2convert.c b/v4l2-apps/libv4l/libv4l2/v4l2convert.c
new file mode 100644
index 000000000..307a03ce5
--- /dev/null
+++ b/v4l2-apps/libv4l/libv4l2/v4l2convert.c
@@ -0,0 +1,166 @@
+/*
+# open/close/ioctl/mmap/munmap library call wrapper doing format conversion
+# for v4l2 applications which want to be able to simply capture bgr24 / yuv420
+# from v4l2 devices with more exotic frame formats.
+
+#             (C) 2008 Hans de Goede <j.w.r.degoede@hhs.nl>
+
+# 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
+*/
+
+#define _LARGEFILE64_SOURCE 1
+
+#include <stdarg.h>
+#include <stdlib.h>
+#include <syscall.h>
+#include <fcntl.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+/* These headers are not needed by us, but by linux/videodev2.h,
+   which is broken on some systems and doesn't include them itself :( */
+#include <sys/time.h>
+#include <asm/types.h>
+#include <linux/ioctl.h>
+/* end broken header workaround includes */
+#include <linux/videodev2.h>
+#include <libv4l2.h>
+
+/* Check that open/read/mmap is not a define */
+#if defined open || defined read || defined mmap
+#error open/read/mmap is a prepocessor macro !!
+#endif
+
+#if __GNUC__ >= 4
+#define LIBV4L_PUBLIC __attribute__ ((visibility("default")))
+#else
+#define LIBV4L_PUBLIC
+#endif
+
+LIBV4L_PUBLIC int open (const char *file, int oflag, ...)
+{
+  int fd;
+  struct v4l2_capability cap;
+  int v4l_device = 0;
+
+  /* check if we're opening a video4linux2 device */
+  if (!strncmp(file, "/dev/video", 10) || !strncmp(file, "/dev/v4l/", 9)) {
+    /* Some apps open the device read only, but we need rw rights as the
+       buffers *MUST* be mapped rw */
+    oflag = (oflag & ~O_ACCMODE) | O_RDWR;
+    v4l_device = 1;
+  }
+
+  /* original open code */
+  if (oflag & O_CREAT)
+  {
+    va_list ap;
+    mode_t mode;
+
+    va_start (ap, oflag);
+    mode = va_arg (ap, mode_t);
+
+    fd = syscall(SYS_open, file, oflag, mode);
+
+    va_end(ap);
+  } else
+    fd = syscall(SYS_open, file, oflag);
+  /* end of original open code */
+
+  if (fd == -1 || !v4l_device)
+    return fd;
+
+  /* check that this is an v4l2 device, libv4l2 only supports v4l2 devices */
+  if (syscall(SYS_ioctl, fd, VIDIOC_QUERYCAP, &cap))
+    return fd;
+
+  /* libv4l2 only adds functionality to capture capable devices */
+  if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE))
+    return fd;
+
+  /* Try to Register with libv4l2 (in case of failure pass the fd to the
+     application as is) */
+  v4l2_fd_open(fd, V4L2_ENABLE_ENUM_FMT_EMULATION);
+
+  return fd;
+}
+
+LIBV4L_PUBLIC int open64(const char *file, int oflag, ...)
+{
+  int fd;
+
+  /* original open code */
+  if (oflag & O_CREAT)
+  {
+    va_list ap;
+    mode_t mode;
+
+    va_start (ap, oflag);
+    mode = va_arg (ap, mode_t);
+
+    fd = open(file, oflag | O_LARGEFILE, mode);
+
+    va_end(ap);
+  } else
+    fd = open(file, oflag | O_LARGEFILE);
+  /* end of original open code */
+
+  return fd;
+}
+
+LIBV4L_PUBLIC int close(int fd)
+{
+  return v4l2_close(fd);
+}
+
+LIBV4L_PUBLIC int dup(int fd)
+{
+  return v4l2_dup(fd);
+}
+
+LIBV4L_PUBLIC int ioctl (int fd, unsigned long int request, ...)
+{
+  void *arg;
+  va_list ap;
+
+  va_start (ap, request);
+  arg = va_arg (ap, void *);
+  va_end (ap);
+
+  return v4l2_ioctl (fd, request, arg);
+}
+
+LIBV4L_PUBLIC ssize_t read (int fd, void* buffer, size_t n)
+{
+  return v4l2_read (fd, buffer, n);
+}
+
+LIBV4L_PUBLIC void *mmap(void *start, size_t length, int prot, int flags, int fd,
+  __off_t offset)
+{
+  return v4l2_mmap(start, length, prot, flags, fd, offset);
+}
+
+LIBV4L_PUBLIC void *mmap64(void *start, size_t length, int prot, int flags, int fd,
+  __off64_t offset)
+{
+  return v4l2_mmap(start, length, prot, flags, fd, offset);
+}
+
+LIBV4L_PUBLIC int munmap(void *start, size_t length)
+{
+  return v4l2_munmap(start, length);
+}
+