/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
 * Copyright (C) 2019, Google Inc.
 *
 * Proxy to V4L2 compatibility camera
 */

#pragma once

#include <linux/videodev2.h>
#include <map>
#include <memory>
#include <set>
#include <sys/types.h>
#include <vector>

#include <libcamera/base/mutex.h>

#include <libcamera/camera.h>

#include "v4l2_camera.h"

class V4L2CameraFile;

class V4L2CameraProxy
{
public:
	V4L2CameraProxy(unsigned int index, std::shared_ptr<libcamera::Camera> camera);

	int open(V4L2CameraFile *file) LIBCAMERA_TSA_EXCLUDES(proxyMutex_);
	void close(V4L2CameraFile *file) LIBCAMERA_TSA_EXCLUDES(proxyMutex_);
	void *mmap(V4L2CameraFile *file, void *addr, size_t length, int prot,
		   int flags, off64_t offset) LIBCAMERA_TSA_EXCLUDES(proxyMutex_);
	int munmap(V4L2CameraFile *file, void *addr, size_t length)
		LIBCAMERA_TSA_EXCLUDES(proxyMutex_);

	int ioctl(V4L2CameraFile *file, unsigned long request, void *arg)
		LIBCAMERA_TSA_EXCLUDES(proxyMutex_);

private:
	bool validateBufferType(uint32_t type);
	bool validateMemoryType(uint32_t memory);
	void setFmtFromConfig(const libcamera::StreamConfiguration &streamConfig);
	void querycap(std::shared_ptr<libcamera::Camera> camera);
	int tryFormat(struct v4l2_format *arg);
	enum v4l2_priority maxPriority();
	void updateBuffers();
	void freeBuffers();

	int vidioc_querycap(V4L2CameraFile *file, struct v4l2_capability *arg);
	int vidioc_enum_framesizes(V4L2CameraFile *file, struct v4l2_frmsizeenum *arg);
	int vidioc_enum_fmt(V4L2CameraFile *file, struct v4l2_fmtdesc *arg);
	int vidioc_g_fmt(V4L2CameraFile *file, struct v4l2_format *arg);
	int vidioc_s_fmt(V4L2CameraFile *file, struct v4l2_format *arg);
	int vidioc_try_fmt(V4L2CameraFile *file, struct v4l2_format *arg);
	int vidioc_g_priority(V4L2CameraFile *file, enum v4l2_priority *arg);
	int vidioc_s_priority(V4L2CameraFile *file, enum v4l2_priority *arg);
	int vidioc_enuminput(V4L2CameraFile *file, struct v4l2_input *arg);
	int vidioc_g_input(V4L2CameraFile *file, int *arg);
	int vidioc_s_input(V4L2CameraFile *file, int *arg);
	int vidioc_reqbufs(V4L2CameraFile *file, struct v4l2_requestbuffers *arg);
	int vidioc_querybuf(V4L2CameraFile *file, struct v4l2_buffer *arg);
	int vidioc_prepare_buf(V4L2CameraFile *file, struct v4l2_buffer *arg);
	int vidioc_qbuf(V4L2CameraFile *file, struct v4l2_buffer *arg);
	int vidioc_dqbuf(V4L2CameraFile *file, struct v4l2_buffer *arg,
			 libcamera::Mutex *lock) LIBCAMERA_TSA_REQUIRES(*lock);
	int vidioc_expbuf(V4L2CameraFile *file, struct v4l2_exportbuffer *arg);
	int vidioc_streamon(V4L2CameraFile *file, int *arg);
	int vidioc_streamoff(V4L2CameraFile *file, int *arg);
	int vidioc_g_parm(V4L2CameraFile *file, struct v4l2_streamparm *arg);
	int vidioc_s_parm(V4L2CameraFile *file, struct v4l2_streamparm *arg);

	bool hasOwnership(V4L2CameraFile *file);
	int acquire(V4L2CameraFile *file);
	void release(V4L2CameraFile *file);

	static const std::set<unsigned long> supportedIoctls_;

	unsigned int refcount_;
	unsigned int index_;

	libcamera::StreamConfiguration streamConfig_;
	unsigned int bufferCount_;
	unsigned int currentBuf_;
	unsigned int sizeimage_;

	struct v4l2_capability capabilities_;
	struct v4l2_pix_format v4l2PixFormat_;
	struct v4l2_fract v4l2TimePerFrame_;

	std::vector<struct v4l2_buffer> buffers_;
	std::map<void *, unsigned int> mmaps_;

	std::set<V4L2CameraFile *> files_;

	std::unique_ptr<V4L2Camera> vcam_;

	/*
	 * This is the exclusive owner of this V4L2CameraProxy instance.
	 * When there is no owner, anybody can call any ioctl before reqbufs.
	 * The first file to call reqbufs with count > 0 or s_fmt will become
	 * the owner, and when the owner calls reqbufs with count = 0 it will
	 * release ownership. Any buffer-related ioctl (except querybuf) or
	 * s_fmt that is called by a non-owner while there exists an owner
	 * will return -EBUSY.
	 */
	V4L2CameraFile *owner_;

	/* This mutex is to serialize access to the proxy. */
	libcamera::Mutex proxyMutex_;
};
2</a>
<a id='n13' href='#n13'>13</a>
<a id='n14' href='#n14'>14</a>
<a id='n15' href='#n15'>15</a>
<a id='n16' href='#n16'>16</a>
<a id='n17' href='#n17'>17</a>
<a id='n18' href='#n18'>18</a>
<a id='n19' href='#n19'>19</a>
<a id='n20' href='#n20'>20</a>
<a id='n21' href='#n21'>21</a>
<a id='n22' href='#n22'>22</a>
<a id='n23' href='#n23'>23</a>
<a id='n24' href='#n24'>24</a>
<a id='n25' href='#n25'>25</a>
<a id='n26' href='#n26'>26</a>
<a id='n27' href='#n27'>27</a>
<a id='n28' href='#n28'>28</a>
<a id='n29' href='#n29'>29</a>
<a id='n30' href='#n30'>30</a>
<a id='n31' href='#n31'>31</a>
<a id='n32' href='#n32'>32</a>
<a id='n33' href='#n33'>33</a>
<a id='n34' href='#n34'>34</a>
<a id='n35' href='#n35'>35</a>
<a id='n36' href='#n36'>36</a>
<a id='n37' href='#n37'>37</a>
<a id='n38' href='#n38'>38</a>
<a id='n39' href='#n39'>39</a>
<a id='n40' href='#n40'>40</a>
<a id='n41' href='#n41'>41</a>
<a id='n42' href='#n42'>42</a>
<a id='n43' href='#n43'>43</a>
<a id='n44' href='#n44'>44</a>
<a id='n45' href='#n45'>45</a>
<a id='n46' href='#n46'>46</a>
<a id='n47' href='#n47'>47</a>
<a id='n48' href='#n48'>48</a>
<a id='n49' href='#n49'>49</a>
<a id='n50' href='#n50'>50</a>
<a id='n51' href='#n51'>51</a>
<a id='n52' href='#n52'>52</a>
<a id='n53' href='#n53'>53</a>
<a id='n54' href='#n54'>54</a>
<a id='n55' href='#n55'>55</a>
<a id='n56' href='#n56'>56</a>
<a id='n57' href='#n57'>57</a>
<a id='n58' href='#n58'>58</a>
<a id='n59' href='#n59'>59</a>
<a id='n60' href='#n60'>60</a>
<a id='n61' href='#n61'>61</a>
<a id='n62' href='#n62'>62</a>
<a id='n63' href='#n63'>63</a>
<a id='n64' href='#n64'>64</a>
<a id='n65' href='#n65'>65</a>
<a id='n66' href='#n66'>66</a>
<a id='n67' href='#n67'>67</a>
<a id='n68' href='#n68'>68</a>
<a id='n69' href='#n69'>69</a>
<a id='n70' href='#n70'>70</a>
<a id='n71' href='#n71'>71</a>
<a id='n72' href='#n72'>72</a>
<a id='n73' href='#n73'>73</a>
<a id='n74' href='#n74'>74</a>
<a id='n75' href='#n75'>75</a>
<a id='n76' href='#n76'>76</a>
<a id='n77' href='#n77'>77</a>
<a id='n78' href='#n78'>78</a>
<a id='n79' href='#n79'>79</a>
<a id='n80' href='#n80'>80</a>
<a id='n81' href='#n81'>81</a>
<a id='n82' href='#n82'>82</a>
<a id='n83' href='#n83'>83</a>
<a id='n84' href='#n84'>84</a>
<a id='n85' href='#n85'>85</a>
<a id='n86' href='#n86'>86</a>
<a id='n87' href='#n87'>87</a>
<a id='n88' href='#n88'>88</a>
<a id='n89' href='#n89'>89</a>
<a id='n90' href='#n90'>90</a>
<a id='n91' href='#n91'>91</a>
<a id='n92' href='#n92'>92</a>
<a id='n93' href='#n93'>93</a>
<a id='n94' href='#n94'>94</a>
<a id='n95' href='#n95'>95</a>
<a id='n96' href='#n96'>96</a>
<a id='n97' href='#n97'>97</a>
<a id='n98' href='#n98'>98</a>
<a id='n99' href='#n99'>99</a>
<a id='n100' href='#n100'>100</a>
<a id='n101' href='#n101'>101</a>
<a id='n102' href='#n102'>102</a>
<a id='n103' href='#n103'>103</a>
<a id='n104' href='#n104'>104</a>
<a id='n105' href='#n105'>105</a>
<a id='n106' href='#n106'>106</a>
<a id='n107' href='#n107'>107</a>
<a id='n108' href='#n108'>108</a>
<a id='n109' href='#n109'>109</a>
<a id='n110' href='#n110'>110</a>
<a id='n111' href='#n111'>111</a>
<a id='n112' href='#n112'>112</a>
<a id='n113' href='#n113'>113</a>
<a id='n114' href='#n114'>114</a>
<a id='n115' href='#n115'>115</a>
<a id='n116' href='#n116'>116</a>
<a id='n117' href='#n117'>117</a>
<a id='n118' href='#n118'>118</a>
<a id='n119' href='#n119'>119</a>
<a id='n120' href='#n120'>120</a>
<a id='n121' href='#n121'>121</a>
<a id='n122' href='#n122'>122</a>
<a id='n123' href='#n123'>123</a>
<a id='n124' href='#n124'>124</a>
<a id='n125' href='#n125'>125</a>
<a id='n126' href='#n126'>126</a>
<a id='n127' href='#n127'>127</a>
<a id='n128' href='#n128'>128</a>
<a id='n129' href='#n129'>129</a>
<a id='n130' href='#n130'>130</a>
<a id='n131' href='#n131'>131</a>
<a id='n132' href='#n132'>132</a>
<a id='n133' href='#n133'>133</a>
<a id='n134' href='#n134'>134</a>
<a id='n135' href='#n135'>135</a>
<a id='n136' href='#n136'>136</a>
<a id='n137' href='#n137'>137</a>
<a id='n138' href='#n138'>138</a>
<a id='n139' href='#n139'>139</a>
<a id='n140' href='#n140'>140</a>
<a id='n141' href='#n141'>141</a>
</pre></td>
<td class='lines'><pre><code><span class="hl com">/* SPDX-License-Identifier: LGPL-2.1-or-later */</span>
<span class="hl com">/*</span>
<span class="hl com"> * Copyright (C) 2019, Google Inc.</span>
<span class="hl com"> *</span>
<span class="hl com"> * event_notifier.cpp - File descriptor event notifier</span>
<span class="hl com"> */</span>

<span class="hl ppc">#include &lt;libcamera/base/event_notifier.h&gt;</span>

<span class="hl ppc">#include &lt;libcamera/base/event_dispatcher.h&gt;</span>
<span class="hl ppc">#include &lt;libcamera/base/message.h&gt;</span>
<span class="hl ppc">#include &lt;libcamera/base/thread.h&gt;</span>

<span class="hl ppc">#include &lt;libcamera/camera_manager.h&gt;</span>

<span class="hl com">/**</span>
<span class="hl com"> * \file event_notifier.h</span>
<span class="hl com"> * \brief File descriptor event notifier</span>
<span class="hl com"> */</span>

<span class="hl kwa">namespace</span> libcamera <span class="hl opt">{</span>

<span class="hl com">/**</span>
<span class="hl com"> * \class EventNotifier</span>
<span class="hl com"> * \brief Notify of activity on a file descriptor</span>
<span class="hl com"> *</span>
<span class="hl com"> * The EventNotifier models a file descriptor event source that can be</span>
<span class="hl com"> * monitored. It is created with the file descriptor to be monitored and the</span>
<span class="hl com"> * type of event, and is enabled by default. It will emit the \ref activated</span>
<span class="hl com"> * signal whenever an event of the monitored type occurs on the file descriptor.</span>
<span class="hl com"> *</span>
<span class="hl com"> * Supported type of events are EventNotifier::Read, EventNotifier::Write and</span>
<span class="hl com"> * EventNotifier::Exception. The type is specified when constructing the</span>
<span class="hl com"> * notifier, and can be retrieved using the type() function. To listen to</span>
<span class="hl com"> * multiple event types on the same file descriptor multiple notifiers must be</span>
<span class="hl com"> * created.</span>
<span class="hl com"> *</span>
<span class="hl com"> * The notifier can be disabled with the setEnabled() function. When the notifier</span>
<span class="hl com"> * is disabled it ignores events and does not emit the \ref activated signal.</span>
<span class="hl com"> * The notifier can then be re-enabled with the setEnabled() function.</span>
<span class="hl com"> *</span>
<span class="hl com"> * Creating multiple notifiers of the same type for the same file descriptor is</span>
<span class="hl com"> * not allowed and results in undefined behaviour.</span>
<span class="hl com"> *</span>
<span class="hl com"> * Notifier events are detected and dispatched from the</span>
<span class="hl com"> * EventDispatcher::processEvents() function.</span>
<span class="hl com"> */</span>

<span class="hl com">/**</span>
<span class="hl com"> * \enum EventNotifier::Type</span>
<span class="hl com"> * Type of file descriptor event to listen for.</span>
<span class="hl com"> * \var EventNotifier::Read</span>
<span class="hl com"> * Data is available to be read from the file descriptor</span>
<span class="hl com"> * \var EventNotifier::Write</span>
<span class="hl com"> * Data can be written to the file descriptor</span>
<span class="hl com"> * \var EventNotifier::Exception</span>
<span class="hl com"> * An exception has occurred on the file descriptor</span>
<span class="hl com"> */</span>

<span class="hl com">/**</span>
<span class="hl com"> * \brief Construct an event notifier with a file descriptor and event type</span>
<span class="hl com"> * \param[in] fd The file descriptor to monitor</span>
<span class="hl com"> * \param[in] type The event type to monitor</span>
<span class="hl com"> * \param[in] parent The parent Object</span>
<span class="hl com"> */</span>
<span class="hl kwc">EventNotifier</span><span class="hl opt">::</span><span class="hl kwd">EventNotifier</span><span class="hl opt">(</span><span class="hl kwb">int</span> fd<span class="hl opt">,</span> Type type<span class="hl opt">,</span> Object <span class="hl opt">*</span>parent<span class="hl opt">)</span>
	<span class="hl opt">:</span> <span class="hl kwd">Object</span><span class="hl opt">(</span>parent<span class="hl opt">),</span> <span class="hl kwd">fd_</span><span class="hl opt">(</span>fd<span class="hl opt">),</span> <span class="hl kwd">type_</span><span class="hl opt">(</span>type<span class="hl opt">),</span> <span class="hl kwd">enabled_</span><span class="hl opt">(</span><span class="hl kwa">false</span><span class="hl opt">)</span>
<span class="hl opt">{</span>
	<span class="hl kwd">setEnabled</span><span class="hl opt">(</span><span class="hl kwa">true</span><span class="hl opt">);</span>
<span class="hl opt">}</span>

<span class="hl kwc">EventNotifier</span><span class="hl opt">::~</span><span class="hl kwd">EventNotifier</span><span class="hl opt">()</span>
<span class="hl opt">{</span>
	<span class="hl kwd">setEnabled</span><span class="hl opt">(</span><span class="hl kwa">false</span><span class="hl opt">);</span>
<span class="hl opt">}</span>

<span class="hl com">/**</span>
<span class="hl com"> * \fn EventNotifier::type()</span>
<span class="hl com"> * \brief Retrieve the type of the event being monitored</span>
<span class="hl com"> * \return The type of the event</span>
<span class="hl com"> */</span>

<span class="hl com">/**</span>
<span class="hl com"> * \fn EventNotifier::fd()</span>
<span class="hl com"> * \brief Retrieve the file descriptor being monitored</span>
<span class="hl com"> * \return The file descriptor</span>
<span class="hl com"> */</span>

<span class="hl com">/**</span>
<span class="hl com"> * \fn EventNotifier::enabled()</span>
<span class="hl com"> * \brief Retrieve the notifier state</span>
<span class="hl com"> * \return True if the notifier is enabled, or false otherwise</span>
<span class="hl com"> * \sa setEnabled()</span>
<span class="hl com"> */</span>

<span class="hl com">/**</span>
<span class="hl com"> * \brief Enable or disable the notifier</span>
<span class="hl com"> * \param[in] enable True to enable the notifier, false to disable it</span>
<span class="hl com"> *</span>
<span class="hl com"> * This function enables or disables the notifier. A disabled notifier ignores</span>
<span class="hl com"> * events and does not emit the \ref activated signal.</span>
<span class="hl com"> *</span>
<span class="hl com"> * \context This function is \threadbound.</span>
<span class="hl com"> */</span>