src/libds/buffer.c

   1 #include <assert.h>
   2 #include <stdlib.h>
   3
   4 #include "buffer.h"
   5 #include "client_buffer.h"
   6 #include "libds/log.h"
   7 #include "libds/interfaces/buffer.h"
   8
   9 static struct wl_array buffer_resource_interfaces = {0};
  10
  11 static void buffer_consider_destroy(struct ds_buffer *buffer);
  12 static bool ds_resource_is_buffer(struct wl_resource *resource);
  13 static const struct ds_buffer_resource_interface *
  14 get_buffer_resource_iface(struct wl_resource *resource);
  15
  16 WL_EXPORT void
  17 ds_buffer_init(struct ds_buffer *buffer, const struct ds_buffer_interface *iface,
  18         int width, int height)
  19 {
  20     buffer->iface = iface;
  21     buffer->width = width;
  22     buffer->height = height;
  23
  24     wl_signal_init(&buffer->events.destroy);
  25     wl_signal_init(&buffer->events.release);
  26 }
  27
  28 WL_EXPORT struct ds_buffer *
  29 ds_buffer_from_resource(struct wl_resource *resource)
  30 {
  31     struct ds_buffer *buffer;
  32     const struct ds_buffer_resource_interface *iface;
  33
  34     assert(resource && ds_resource_is_buffer(resource));
  35
  36     if (wl_shm_buffer_get(resource) != NULL) {
  37         struct ds_shm_client_buffer *shm_client_buffer =
  38             ds_shm_client_buffer_get_or_create(resource);
  39         if (!shm_client_buffer) {
  40             ds_err("Failed to create shm client buffer");
  41             return NULL;
  42         }
  43
  44         buffer = ds_buffer_lock(&shm_client_buffer->base);
  45     }
  46     else {
  47         iface = get_buffer_resource_iface(resource);
  48         if (!iface) {
  49             ds_err("Unknown buffer type");
  50             return NULL;
  51         }
  52
  53         buffer = iface->from_resource(resource);
  54         if (!buffer) {
  55             ds_err("Failed to create %s buffer", iface->name);
  56             return NULL;
  57         }
  58
  59         buffer = ds_buffer_lock(buffer);
  60     }
  61
  62     return buffer;
  63 }
  64
  65 WL_EXPORT void
  66 ds_buffer_drop(struct ds_buffer *buffer)
  67 {
  68     assert(!buffer->dropped);
  69     buffer->dropped = true;
  70     ds_dbg("Buffer(%p) dropped: n_locks(%zu)", buffer, buffer->n_locks);
  71     buffer_consider_destroy(buffer);
  72 }
  73
  74 WL_EXPORT struct ds_buffer *
  75 ds_buffer_lock(struct ds_buffer *buffer)
  76 {
  77     buffer->n_locks++;
  78     ds_dbg("Buffer(%p) n_locks(%zu)", buffer, buffer->n_locks);
  79     return buffer;
  80 }
  81
  82 WL_EXPORT void
  83 ds_buffer_unlock(struct ds_buffer *buffer)
  84 {
  85     assert(buffer->n_locks > 0);
  86     buffer->n_locks--;
  87     ds_dbg("Buffer(%p) n_locks(%zu)", buffer, buffer->n_locks);
  88
  89     if (buffer->n_locks == 0)
  90         wl_signal_emit(&buffer->events.release, NULL);
  91
  92     buffer_consider_destroy(buffer);
  93 }
  94
  95 WL_EXPORT bool
  96 ds_buffer_begin_data_ptr_access(struct ds_buffer *buffer, uint32_t flags,
  97         void **data, uint32_t *format, size_t *stride)
  98 {
  99     assert(!buffer->accessing_data_ptr);
 100     if (!buffer->iface->begin_data_ptr_access)
 101         return false;
 102     if (!buffer->iface->begin_data_ptr_access(buffer, flags, data, format, stride))
 103         return false;
 104     buffer->accessing_data_ptr = true;
 105     return true;
 106 }
 107
 108 WL_EXPORT void
 109 ds_buffer_end_data_ptr_access(struct ds_buffer *buffer)
 110 {
 111     assert(buffer->accessing_data_ptr);
 112     buffer->iface->end_data_ptr_access(buffer);
 113     buffer->accessing_data_ptr = false;
 114 }
 115
 116 WL_EXPORT void
 117 ds_buffer_add_destroy_listener(struct ds_buffer *buffer,
 118         struct wl_listener *listener)
 119 {
 120     wl_signal_add(&buffer->events.destroy, listener);
 121 }
 122
 123 void
 124 ds_buffer_add_release_listener(struct ds_buffer *buffer,
 125         struct wl_listener *listener)
 126 {
 127     wl_signal_add(&buffer->events.release, listener);
 128 }
 129
 130 WL_EXPORT bool
 131 ds_buffer_get_shm(struct ds_buffer *buffer, struct ds_shm_attributes *attribs)
 132 {
 133     if (!buffer->iface->get_shm)
 134         return false;
 135
 136     return buffer->iface->get_shm(buffer, attribs);
 137 }
 138
 139 WL_EXPORT void
 140 ds_buffer_get_size(struct ds_buffer *buffer, int *out_width, int *out_height)
 141 {
 142     if (out_width)
 143         *out_width = buffer->width;
 144     if (out_height)
 145         *out_height = buffer->height;
 146 }
 147
 148 WL_EXPORT void
 149 ds_buffer_register_resource_interface(
 150         const struct ds_buffer_resource_interface *iface)
 151 {
 152     const struct ds_buffer_resource_interface **iface_ptr;
 153
 154     assert(iface);
 155     assert(iface->is_instance);
 156     assert(iface->from_resource);
 157
 158     wl_array_for_each(iface_ptr, &buffer_resource_interfaces) {
 159         if (*iface_ptr == iface) {
 160             ds_dbg("ds_buffer_resource_interface %s has already "
 161                     "been registered", iface->name);
 162             return;
 163         }
 164     }
 165
 166     iface_ptr = wl_array_add(&buffer_resource_interfaces, sizeof(iface));
 167     *iface_ptr = iface;
 168 }
 169
 170 static void
 171 buffer_consider_destroy(struct ds_buffer *buffer)
 172 {
 173     if (!buffer->dropped || buffer->n_locks > 0)
 174         return;
 175
 176     assert(!buffer->accessing_data_ptr);
 177
 178     wl_signal_emit(&buffer->events.destroy, NULL);
 179     buffer->iface->destroy(buffer);
 180 }
 181
 182 static bool
 183 ds_resource_is_buffer(struct wl_resource *resource)
 184 {
 185     return strcmp(wl_resource_get_class(resource),
 186             wl_buffer_interface.name) == 0;
 187 }
 188
 189 static const struct ds_buffer_resource_interface *
 190 get_buffer_resource_iface(struct wl_resource *resource)
 191 {
 192     struct ds_buffer_resource_interface **iface_ptr;
 193
 194     wl_array_for_each(iface_ptr, &buffer_resource_interfaces) {
 195         if ((*iface_ptr)->is_instance(resource)) {
 196             return *iface_ptr;
 197         }
 198     }
 199
 200     return NULL;
 201 }