1 /* GStreamer Wayland video sink
2  *
3  * Copyright (C) 2012 Intel Corporation
4  * Copyright (C) 2012 Sreerenj Balachandran <sreerenj.balachandran@intel.com>
5  * Copyright (C) 2014 Collabora Ltd.
6  *
7  * This library is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Library General Public
9  * License as published by the Free Software Foundation; either
10  * version 2 of the License, or (at your option) any later version.
11  *
12  * This library is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Library General Public License for more details.
16  *
17  * You should have received a copy of the GNU Library General Public
18  * License along with this library; if not, write to the
19  * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
20  * Boston, MA 02110-1301, USA.
21  */
22 
23 #include "wlshmallocator.h"
24 #include "wlvideoformat.h"
25 
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <errno.h>
30 #include <unistd.h>
31 #include <sys/mman.h>
32 #include <sys/types.h>
33 
34 GST_DEBUG_CATEGORY_EXTERN (gstwayland_debug);
35 #define GST_CAT_DEFAULT gstwayland_debug
36 
37 G_DEFINE_TYPE (GstWlShmAllocator, gst_wl_shm_allocator, GST_TYPE_FD_ALLOCATOR);
38 
39 static GstMemory *
gst_wl_shm_allocator_alloc(GstAllocator * allocator,gsize size,GstAllocationParams * params)40 gst_wl_shm_allocator_alloc (GstAllocator * allocator, gsize size,
41     GstAllocationParams * params)
42 {
43   GstWlShmAllocator *self = GST_WL_SHM_ALLOCATOR (allocator);
44   char filename[1024];
45   static int init = 0;
46   int fd;
47   GstMemory *mem;
48   GstMapInfo info;
49 
50   /* TODO: make use of the allocation params, if necessary */
51 
52   /* allocate shm pool */
53   snprintf (filename, 1024, "%s/%s-%d-%s", g_get_user_runtime_dir (),
54       "wayland-shm", init++, "XXXXXX");
55 
56   fd = g_mkstemp (filename);
57   if (fd < 0) {
58     GST_ERROR_OBJECT (self, "opening temp file %s failed: %s", filename,
59         strerror (errno));
60     return NULL;
61   }
62   if (ftruncate (fd, size) < 0) {
63     GST_ERROR_OBJECT (self, "ftruncate failed: %s", strerror (errno));
64     close (fd);
65     return NULL;
66   }
67 
68   mem = gst_fd_allocator_alloc (allocator, fd, size,
69       GST_FD_MEMORY_FLAG_KEEP_MAPPED);
70   if (G_UNLIKELY (!mem)) {
71     GST_ERROR_OBJECT (self, "GstFdMemory allocation failed");
72     close (fd);
73     return NULL;
74   }
75 
76   /* we need to map the memory in order to unlink the file without losing it */
77   if (!gst_memory_map (mem, &info, GST_MAP_READWRITE)) {
78     GST_ERROR_OBJECT (self, "GstFdMemory map failed");
79     close (fd);
80     return NULL;
81   }
82 
83   /* unmap will not really munmap(), we just
84    * need it to release the miniobject lock */
85   gst_memory_unmap (mem, &info);
86 
87   unlink (filename);
88 
89   return mem;
90 }
91 
92 static void
gst_wl_shm_allocator_class_init(GstWlShmAllocatorClass * klass)93 gst_wl_shm_allocator_class_init (GstWlShmAllocatorClass * klass)
94 {
95   GstAllocatorClass *alloc_class = (GstAllocatorClass *) klass;
96 
97   alloc_class->alloc = GST_DEBUG_FUNCPTR (gst_wl_shm_allocator_alloc);
98 }
99 
100 static void
gst_wl_shm_allocator_init(GstWlShmAllocator * self)101 gst_wl_shm_allocator_init (GstWlShmAllocator * self)
102 {
103   GstAllocator *alloc = GST_ALLOCATOR_CAST (self);
104 
105   alloc->mem_type = GST_ALLOCATOR_WL_SHM;
106 
107   GST_OBJECT_FLAG_UNSET (self, GST_ALLOCATOR_FLAG_CUSTOM_ALLOC);
108 }
109 
110 void
gst_wl_shm_allocator_register(void)111 gst_wl_shm_allocator_register (void)
112 {
113   GstAllocator *alloc;
114 
115   alloc = g_object_new (GST_TYPE_WL_SHM_ALLOCATOR, NULL);
116   gst_object_ref_sink (alloc);
117   gst_allocator_register (GST_ALLOCATOR_WL_SHM, alloc);
118 }
119 
120 GstAllocator *
gst_wl_shm_allocator_get(void)121 gst_wl_shm_allocator_get (void)
122 {
123   return gst_allocator_find (GST_ALLOCATOR_WL_SHM);
124 }
125 
126 gboolean
gst_is_wl_shm_memory(GstMemory * mem)127 gst_is_wl_shm_memory (GstMemory * mem)
128 {
129   return gst_memory_is_type (mem, GST_ALLOCATOR_WL_SHM);
130 }
131 
132 /* Copied from gst_v4l2_object_extrapolate_stride() */
133 static gint
gst_wl_shm_extrapolate_stride(const GstVideoFormatInfo * finfo,gint plane,gint stride)134 gst_wl_shm_extrapolate_stride (const GstVideoFormatInfo * finfo, gint plane,
135     gint stride)
136 {
137   gint estride;
138 
139   switch (finfo->format) {
140     case GST_VIDEO_FORMAT_NV12:
141     case GST_VIDEO_FORMAT_NV12_64Z32:
142     case GST_VIDEO_FORMAT_NV21:
143     case GST_VIDEO_FORMAT_NV16:
144     case GST_VIDEO_FORMAT_NV61:
145     case GST_VIDEO_FORMAT_NV24:
146       estride = (plane == 0 ? 1 : 2) *
147           GST_VIDEO_FORMAT_INFO_SCALE_WIDTH (finfo, plane, stride);
148       break;
149     default:
150       estride = GST_VIDEO_FORMAT_INFO_SCALE_WIDTH (finfo, plane, stride);
151       break;
152   }
153 
154   return estride;
155 }
156 
157 static gboolean
gst_wl_shm_validate_video_info(const GstVideoInfo * vinfo)158 gst_wl_shm_validate_video_info (const GstVideoInfo * vinfo)
159 {
160   gint height = GST_VIDEO_INFO_HEIGHT (vinfo);
161   gint base_stride = GST_VIDEO_INFO_PLANE_STRIDE (vinfo, 0);
162   gsize base_offs = GST_VIDEO_INFO_PLANE_OFFSET (vinfo, 0);
163   gint i;
164   gsize offs = 0;
165 
166   for (i = 0; i < GST_VIDEO_INFO_N_PLANES (vinfo); i++) {
167     guint32 estride;
168 
169     /* Overwrite the video info's stride and offset using the pitch calculcated
170      * by the kms driver. */
171     estride = gst_wl_shm_extrapolate_stride (vinfo->finfo, i, base_stride);
172 
173     if (estride != GST_VIDEO_INFO_PLANE_STRIDE (vinfo, i))
174       return FALSE;
175 
176     if (GST_VIDEO_INFO_PLANE_OFFSET (vinfo, i) - base_offs != offs)
177       return FALSE;
178 
179     /* Note that we cannot negotiate special padding betweem each planes,
180      * hence using the display height here. */
181     offs +=
182         estride * GST_VIDEO_FORMAT_INFO_SCALE_HEIGHT (vinfo->finfo, i, height);
183   }
184 
185   if (vinfo->size < offs)
186     return FALSE;
187 
188   return TRUE;
189 }
190 
191 struct wl_buffer *
gst_wl_shm_memory_construct_wl_buffer(GstMemory * mem,GstWlDisplay * display,const GstVideoInfo * info)192 gst_wl_shm_memory_construct_wl_buffer (GstMemory * mem, GstWlDisplay * display,
193     const GstVideoInfo * info)
194 {
195   gint width, height, stride;
196   gsize offset, size, memsize, maxsize;
197   enum wl_shm_format format;
198   struct wl_shm_pool *wl_pool;
199   struct wl_buffer *wbuffer;
200 
201   if (!gst_wl_shm_validate_video_info (info)) {
202     GST_DEBUG_OBJECT (display, "Unsupported strides and offsets.");
203     return NULL;
204   }
205 
206   width = GST_VIDEO_INFO_WIDTH (info);
207   height = GST_VIDEO_INFO_HEIGHT (info);
208   stride = GST_VIDEO_INFO_PLANE_STRIDE (info, 0);
209   size = GST_VIDEO_INFO_SIZE (info);
210   format = gst_video_format_to_wl_shm_format (GST_VIDEO_INFO_FORMAT (info));
211 
212   memsize = gst_memory_get_sizes (mem, &offset, &maxsize);
213   offset += GST_VIDEO_INFO_PLANE_OFFSET (info, 0);
214 
215   g_return_val_if_fail (gst_is_fd_memory (mem), NULL);
216   g_return_val_if_fail (size <= memsize, NULL);
217   g_return_val_if_fail (gst_wl_display_check_format_for_shm (display,
218           GST_VIDEO_INFO_FORMAT (info)), NULL);
219 
220   GST_DEBUG_OBJECT (display, "Creating wl_buffer from SHM of size %"
221       G_GSSIZE_FORMAT " (%d x %d, stride %d), format %s", size, width, height,
222       stride, gst_wl_shm_format_to_string (format));
223 
224   wl_pool = wl_shm_create_pool (display->shm, gst_fd_memory_get_fd (mem),
225       memsize);
226   wbuffer = wl_shm_pool_create_buffer (wl_pool, offset, width, height, stride,
227       format);
228   wl_shm_pool_destroy (wl_pool);
229 
230   return wbuffer;
231 }
232