added linux test module with first implementation of a screengrabber using the xshm extension for x11

test/CMakeLists.txt

@@ -8,3 +8,7 @@ endif()
 if(APPLE AND UNIX)
 	add_subdirectory(osx)
 endif()
+
+if("${CMAKE_SYSTEM_NAME}" MATCHES "Linux")
+    add_subdirectory(linux)
+endif()

test/linux/CMakeLists.txt

@@ -0,0 +1,29 @@
+project(linux)
+
+find_package(X11 REQUIRED)
+
+include_directories(SYSTEM "${CMAKE_SOURCE_DIR}/libobs")
+#include_directories(SYSTEM "${CMAKE_SOURCE_DIR}/libobs-opengl")
+
+set(linux_SOURCES
+    linux.c
+    xshm-input.c
+)
+set(linux_HEADERS
+    linux.h
+    xshm-input.h
+)
+    
+add_library(linux MODULE
+    ${linux_SOURCES}
+    ${linux_HEADERS}
+)
+target_link_libraries(linux
+    libobs
+    ${X11_LIBRARIES}
+    ${X11_XShm_LIB}
+)
+
+install_obs_plugin(linux)
+
+#obs_fixup_install_target(xshm-input PATH ${Libx264_LIBRARIES})

test/linux/linux.c

@@ -0,0 +1,25 @@
+#include <obs.h>
+#include "linux.h"
+
+const char *inputs[] = {
+    "xshm_input"
+};
+
+uint32_t module_version(uint32_t in_version)
+{
+    return LIBOBS_API_VER;
+}
+
+bool enum_inputs(size_t idx, const char **name)
+{
+    if (idx >= (sizeof(inputs)/sizeof(const char*)))
+        return false;
+
+    *name = inputs[idx];
+    return true;
+}
+
+bool enum_filters(size_t idx, const char **name)
+{
+    return false;
+}

test/linux/linux.h

@@ -0,0 +1,15 @@
+#pragma once
+
+#include <util/c99defs.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+EXPORT uint32_t module_version(uint32_t in_version);
+EXPORT bool enum_inputs(size_t idx, const char **name);
+EXPORT bool enum_filters(size_t idx, const char **name);
+
+#ifdef __cplusplus
+}
+#endif

test/linux/xshm-input.c

@@ -0,0 +1,173 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/shm.h>
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include <X11/extensions/XShm.h>
+#include "xshm-input.h"
+
+struct xshm_data {
+    Display *dpy;
+    Screen *screen;
+    Window root_window;
+    Visual *visual;
+    int depth;
+    uint32_t width, height;
+    int shm_attached;
+    XShmSegmentInfo shm_info;
+    XImage *image;
+    texture_t texture;
+};
+
+const char* xshm_input_getname(const char* locale)
+{
+    return "X11 Shared Memory Screen Input";
+}
+
+struct xshm_data *xshm_input_create(const char *settings, obs_source_t source)
+{
+    // create data structure
+    struct xshm_data *data = bmalloc(sizeof(struct xshm_data));
+    memset(data, 0, sizeof(struct xshm_data));
+    
+    // try to open display and all the good stuff
+    data->dpy = XOpenDisplay(NULL);
+    if (!data->dpy)
+        goto fail;
+    
+    data->screen = XDefaultScreenOfDisplay(data->dpy);
+    data->width = WidthOfScreen(data->screen);
+    data->height = HeightOfScreen(data->screen);
+    data->root_window = XRootWindowOfScreen(data->screen);
+    data->visual = DefaultVisualOfScreen(data->screen);
+    data->depth = DefaultDepthOfScreen(data->screen);
+    
+    // query for shm extension
+    if (!XShmQueryExtension(data->dpy))
+        goto fail;
+    
+    // create xshm image
+    data->image = XShmCreateImage(data->dpy, data->visual, data->depth,
+                                  ZPixmap, NULL, &data->shm_info,
+                                  data->width, data->height);
+    if (!data->image)
+        goto fail;
+    
+    printf("Image size: %dx%d\n", data->image->width, data->image->height);
+    
+    // create shared memory
+    data->shm_info.shmid = shmget(IPC_PRIVATE, data->image->bytes_per_line *
+                                  data->image->height, IPC_CREAT | 0700);
+    if (data->shm_info.shmid < 0) {
+        printf("Failed to create shared memory !\n");
+        goto fail;
+    }
+    
+    // attach shared memory
+    data->shm_info.shmaddr = data->image->data 
+                           = (char *) shmat(data->shm_info.shmid, 0, 0);
+    if (data->shm_info.shmaddr == (char *) -1) {
+        printf("Failed to attach shared memory !\n");
+        goto fail;
+    }
+    // set shared memory as read only
+    data->shm_info.readOnly = False;
+    
+    // attach shm
+    if (!XShmAttach(data->dpy, &data->shm_info)) {
+        printf("Failed to attach to XShm !\n");
+        goto fail;
+    }
+    data->shm_attached = 1;
+
+    // get image
+    if (!XShmGetImage(data->dpy, data->root_window, data->image,
+                      0, 0, AllPlanes)) {
+        printf("Failed to get image data !\n");
+        goto fail;
+    }
+
+    // create obs texture    
+    gs_entercontext(obs_graphics());
+    data->texture = gs_create_texture(data->width, data->height, GS_BGRA, 1,
+                                      (const void**) &data->image->data,
+                                      GS_DYNAMIC);
+    gs_leavecontext();
+    
+    if (!data->texture)
+        goto fail;
+    
+    return data;
+    
+fail:
+    // clean up and return null
+    xshm_input_destroy(data);
+    return NULL;
+}
+
+void xshm_input_destroy(struct xshm_data *data)
+{
+    if (data) {
+        gs_entercontext(obs_graphics());
+
+        texture_destroy(data->texture);
+
+        gs_leavecontext();
+        
+        // detach xshm
+        if (data->shm_attached)
+            XShmDetach(data->dpy, &data->shm_info);
+        
+        // detach shared memory
+        if (data->shm_info.shmaddr != (char *) -1) {
+            shmdt(data->shm_info.shmaddr);
+            data->shm_info.shmaddr = (char *) -1;
+        }
+        
+        // remove shared memory
+        if (data->shm_info.shmid != -1)
+            shmctl(data->shm_info.shmid, IPC_RMID, NULL);
+        
+        // destroy image
+        if (data->image)
+            XDestroyImage(data->image);
+        
+        // close display
+        if (data->dpy)
+            XCloseDisplay(data->dpy);
+            
+        bfree(data);
+    }
+}
+
+uint32_t xshm_input_get_output_flags(struct xshm_data *data)
+{
+    return SOURCE_VIDEO | SOURCE_DEFAULT_EFFECT;
+}
+
+void xshm_input_video_render(struct xshm_data *data, obs_source_t filter_target)
+{
+    // update texture
+    if (!XShmGetImage(data->dpy, data->root_window, data->image,
+                      0, 0, AllPlanes)) {
+        printf("Failed to get image !\n");
+    }
+    texture_setimage(data->texture, (void *) data->image->data,
+                     data->width * 4, False);
+    
+    //effect_t effect  = gs_geteffect();
+    //eparam_t diffuse = effect_getparambyname(effect, "diffuse");
+
+    //effect_settexture(effect, diffuse, data->texture);
+    gs_draw_sprite(data->texture, 0, 0, 0);
+}
+
+uint32_t xshm_input_getwidth(struct xshm_data *data)
+{
+    return texture_getwidth(data->texture);
+}
+
+uint32_t xshm_input_getheight(struct xshm_data *data)
+{
+    return texture_getheight(data->texture);
+}

test/linux/xshm-input.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <obs.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// forward declare struct, so we don't have to include X11 headers here
+struct xshm_data;
+    
+EXPORT const char *xshm_input_getname(const char *locale);
+
+EXPORT struct xshm_data *xshm_input_create(const char *settings,
+        obs_source_t source);
+EXPORT void xshm_input_destroy(struct xshm_data *data);
+EXPORT uint32_t xshm_input_get_output_flags(struct xshm_data *data);
+
+EXPORT void xshm_input_video_render(struct xshm_data *data,
+        obs_source_t filter_target);
+
+EXPORT uint32_t xshm_input_getwidth(struct xshm_data *data);
+EXPORT uint32_t xshm_input_getheight(struct xshm_data *data);
+
+#ifdef __cplusplus
+}
+#endif