Loader.cpp revision 1508ae60cc02d0ed84f216f3ddd43a932c2ede42 
1/*
2 ** Copyright 2007, The Android Open Source Project
3 **
4 ** Licensed under the Apache License, Version 2.0 (the "License");
5 ** you may not use this file except in compliance with the License.
6 ** You may obtain a copy of the License at
7 **
8 **     http://www.apache.org/licenses/LICENSE-2.0
9 **
10 ** Unless required by applicable law or agreed to in writing, software
11 ** distributed under the License is distributed on an "AS IS" BASIS,
12 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 ** See the License for the specific language governing permissions and
14 ** limitations under the License.
15 */
16
17//#define LOG_NDEBUG 0
18#define ATRACE_TAG ATRACE_TAG_GRAPHICS
19
20#include <array>
21#include <ctype.h>
22#include <dirent.h>
23#include <dlfcn.h>
24#include <errno.h>
25#include <limits.h>
26#include <stdio.h>
27#include <stdlib.h>
28#include <string.h>
29
30#include <android/dlext.h>
31#include <cutils/properties.h>
32#include <log/log.h>
33#include <utils/Trace.h>
34
35#include <EGL/egl.h>
36
37#include "egldefs.h"
38#include "Loader.h"
39
40// ----------------------------------------------------------------------------
41namespace android {
42// ----------------------------------------------------------------------------
43
44
45/*
46 * EGL userspace drivers must be provided either:
47 * - as a single library:
48 *      /vendor/lib/egl/libGLES.so
49 *
50 * - as separate libraries:
51 *      /vendor/lib/egl/libEGL.so
52 *      /vendor/lib/egl/libGLESv1_CM.so
53 *      /vendor/lib/egl/libGLESv2.so
54 *
55 * The software renderer for the emulator must be provided as a single
56 * library at:
57 *
58 *      /system/lib/egl/libGLES_android.so
59 *
60 *
61 * For backward compatibility and to facilitate the transition to
62 * this new naming scheme, the loader will additionally look for:
63 *
64 *      /{vendor|system}/lib/egl/lib{GLES | [EGL|GLESv1_CM|GLESv2]}_*.so
65 *
66 */
67
68ANDROID_SINGLETON_STATIC_INSTANCE( Loader )
69
70/* This function is called to check whether we run inside the emulator,
71 * and if this is the case whether GLES GPU emulation is supported.
72 *
73 * Returned values are:
74 *  -1   -> not running inside the emulator
75 *   0   -> running inside the emulator, but GPU emulation not supported
76 *   1   -> running inside the emulator, GPU emulation is supported
77 *          through the "emulation" host-side OpenGL ES implementation.
78 *   2   -> running inside the emulator, GPU emulation is supported
79 *          through a guest-side vendor driver's OpenGL ES implementation.
80 */
81static int
82checkGlesEmulationStatus(void)
83{
84    /* We're going to check for the following kernel parameters:
85     *
86     *    qemu=1                      -> tells us that we run inside the emulator
87     *    android.qemu.gles=<number>  -> tells us the GLES GPU emulation status
88     *
89     * Note that we will return <number> if we find it. This let us support
90     * more additionnal emulation modes in the future.
91     */
92    char  prop[PROPERTY_VALUE_MAX];
93    int   result = -1;
94
95    /* First, check for qemu=1 */
96    property_get("ro.kernel.qemu",prop,"0");
97    if (atoi(prop) != 1)
98        return -1;
99
100    /* We are in the emulator, get GPU status value */
101    property_get("qemu.gles",prop,"0");
102    return atoi(prop);
103}
104
105// ----------------------------------------------------------------------------
106
107static char const * getProcessCmdline() {
108    long pid = getpid();
109    char procPath[128];
110    snprintf(procPath, 128, "/proc/%ld/cmdline", pid);
111    FILE * file = fopen(procPath, "r");
112    if (file) {
113        static char cmdline[256];
114        char *str = fgets(cmdline, sizeof(cmdline) - 1, file);
115        fclose(file);
116        if (str) {
117            return cmdline;
118        }
119    }
120    return NULL;
121}
122
123static void* do_dlopen(const char* path, int mode) {
124    ATRACE_CALL();
125    return dlopen(path, mode);
126}
127
128// ----------------------------------------------------------------------------
129
130Loader::driver_t::driver_t(void* gles)
131{
132    dso[0] = gles;
133    for (size_t i=1 ; i<NELEM(dso) ; i++)
134        dso[i] = 0;
135}
136
137Loader::driver_t::~driver_t()
138{
139    for (size_t i=0 ; i<NELEM(dso) ; i++) {
140        if (dso[i]) {
141            dlclose(dso[i]);
142            dso[i] = 0;
143        }
144    }
145}
146
147status_t Loader::driver_t::set(void* hnd, int32_t api)
148{
149    switch (api) {
150        case EGL:
151            dso[0] = hnd;
152            break;
153        case GLESv1_CM:
154            dso[1] = hnd;
155            break;
156        case GLESv2:
157            dso[2] = hnd;
158            break;
159        default:
160            return BAD_INDEX;
161    }
162    return NO_ERROR;
163}
164
165// ----------------------------------------------------------------------------
166
167Loader::Loader()
168    : getProcAddress(NULL),
169      mLibGui(nullptr),
170      mGetDriverNamespace(nullptr)
171{
172    // FIXME: See note in GraphicsEnv.h about android_getDriverNamespace().
173    // libgui should already be loaded in any process that uses libEGL, but
174    // if for some reason it isn't, then we're not going to get a driver
175    // namespace anyway, so don't force it to be loaded.
176    mLibGui = dlopen("libgui.so", RTLD_NOLOAD | RTLD_LOCAL | RTLD_LAZY);
177    if (!mLibGui) {
178        ALOGD("failed to load libgui: %s", dlerror());
179        return;
180    }
181    mGetDriverNamespace = reinterpret_cast<decltype(mGetDriverNamespace)>(
182            dlsym(mLibGui, "android_getDriverNamespace"));
183}
184
185Loader::~Loader() {
186    if (mLibGui)
187        dlclose(mLibGui);
188}
189
190static void* load_wrapper(const char* path) {
191    void* so = do_dlopen(path, RTLD_NOW | RTLD_LOCAL);
192    ALOGE_IF(!so, "dlopen(\"%s\") failed: %s", path, dlerror());
193    return so;
194}
195
196#ifndef EGL_WRAPPER_DIR
197#if defined(__LP64__)
198#define EGL_WRAPPER_DIR "/system/lib64"
199#else
200#define EGL_WRAPPER_DIR "/system/lib"
201#endif
202#endif
203
204static void setEmulatorGlesValue(void) {
205    char prop[PROPERTY_VALUE_MAX];
206    property_get("ro.kernel.qemu", prop, "0");
207    if (atoi(prop) != 1) return;
208
209    property_get("ro.kernel.qemu.gles",prop,"0");
210    if (atoi(prop) == 1) {
211        ALOGD("Emulator has host GPU support, qemu.gles is set to 1.");
212        property_set("qemu.gles", "1");
213        return;
214    }
215
216    // for now, checking the following
217    // directory is good enough for emulator system images
218    const char* vendor_lib_path =
219#if defined(__LP64__)
220        "/vendor/lib64/egl";
221#else
222        "/vendor/lib/egl";
223#endif
224
225    const bool has_vendor_lib = (access(vendor_lib_path, R_OK) == 0);
226    if (has_vendor_lib) {
227        ALOGD("Emulator has vendor provided software renderer, qemu.gles is set to 2.");
228        property_set("qemu.gles", "2");
229    } else {
230        ALOGD("Emulator without GPU support detected. "
231              "Fallback to legacy software renderer, qemu.gles is set to 0.");
232        property_set("qemu.gles", "0");
233    }
234}
235
236void* Loader::open(egl_connection_t* cnx)
237{
238    ATRACE_CALL();
239
240    void* dso;
241    driver_t* hnd = 0;
242
243    setEmulatorGlesValue();
244
245    dso = load_driver("GLES", cnx, EGL | GLESv1_CM | GLESv2);
246    if (dso) {
247        hnd = new driver_t(dso);
248    } else {
249        // Always load EGL first
250        dso = load_driver("EGL", cnx, EGL);
251        if (dso) {
252            hnd = new driver_t(dso);
253            hnd->set( load_driver("GLESv1_CM", cnx, GLESv1_CM), GLESv1_CM );
254            hnd->set( load_driver("GLESv2",    cnx, GLESv2),    GLESv2 );
255        }
256    }
257
258    LOG_ALWAYS_FATAL_IF(!hnd, "couldn't find an OpenGL ES implementation");
259
260    cnx->libEgl   = load_wrapper(EGL_WRAPPER_DIR "/libEGL.so");
261    cnx->libGles2 = load_wrapper(EGL_WRAPPER_DIR "/libGLESv2.so");
262    cnx->libGles1 = load_wrapper(EGL_WRAPPER_DIR "/libGLESv1_CM.so");
263
264    LOG_ALWAYS_FATAL_IF(!cnx->libEgl,
265            "couldn't load system EGL wrapper libraries");
266
267    LOG_ALWAYS_FATAL_IF(!cnx->libGles2 || !cnx->libGles1,
268            "couldn't load system OpenGL ES wrapper libraries");
269
270    return (void*)hnd;
271}
272
273status_t Loader::close(void* driver)
274{
275    driver_t* hnd = (driver_t*)driver;
276    delete hnd;
277    return NO_ERROR;
278}
279
280void Loader::init_api(void* dso,
281        char const * const * api,
282        __eglMustCastToProperFunctionPointerType* curr,
283        getProcAddressType getProcAddress)
284{
285    ATRACE_CALL();
286
287    const ssize_t SIZE = 256;
288    char scrap[SIZE];
289    while (*api) {
290        char const * name = *api;
291        __eglMustCastToProperFunctionPointerType f =
292            (__eglMustCastToProperFunctionPointerType)dlsym(dso, name);
293        if (f == NULL) {
294            // couldn't find the entry-point, use eglGetProcAddress()
295            f = getProcAddress(name);
296        }
297        if (f == NULL) {
298            // Try without the OES postfix
299            ssize_t index = ssize_t(strlen(name)) - 3;
300            if ((index>0 && (index<SIZE-1)) && (!strcmp(name+index, "OES"))) {
301                strncpy(scrap, name, index);
302                scrap[index] = 0;
303                f = (__eglMustCastToProperFunctionPointerType)dlsym(dso, scrap);
304                //ALOGD_IF(f, "found <%s> instead", scrap);
305            }
306        }
307        if (f == NULL) {
308            // Try with the OES postfix
309            ssize_t index = ssize_t(strlen(name)) - 3;
310            if (index>0 && strcmp(name+index, "OES")) {
311                snprintf(scrap, SIZE, "%sOES", name);
312                f = (__eglMustCastToProperFunctionPointerType)dlsym(dso, scrap);
313                //ALOGD_IF(f, "found <%s> instead", scrap);
314            }
315        }
316        if (f == NULL) {
317            //ALOGD("%s", name);
318            f = (__eglMustCastToProperFunctionPointerType)gl_unimplemented;
319
320            /*
321             * GL_EXT_debug_label is special, we always report it as
322             * supported, it's handled by GLES_trace. If GLES_trace is not
323             * enabled, then these are no-ops.
324             */
325            if (!strcmp(name, "glInsertEventMarkerEXT")) {
326                f = (__eglMustCastToProperFunctionPointerType)gl_noop;
327            } else if (!strcmp(name, "glPushGroupMarkerEXT")) {
328                f = (__eglMustCastToProperFunctionPointerType)gl_noop;
329            } else if (!strcmp(name, "glPopGroupMarkerEXT")) {
330                f = (__eglMustCastToProperFunctionPointerType)gl_noop;
331            }
332        }
333        *curr++ = f;
334        api++;
335    }
336}
337
338static void* load_system_driver(const char* kind) {
339    ATRACE_CALL();
340    class MatchFile {
341    public:
342        static String8 find(const char* kind) {
343            String8 result;
344            int emulationStatus = checkGlesEmulationStatus();
345            switch (emulationStatus) {
346                case 0:
347#if defined(__LP64__)
348                    result.setTo("/system/lib64/egl/libGLES_android.so");
349#else
350                    result.setTo("/system/lib/egl/libGLES_android.so");
351#endif
352                    return result;
353                case 1:
354                    // Use host-side OpenGL through the "emulation" library
355#if defined(__LP64__)
356                    result.appendFormat("/system/lib64/egl/lib%s_emulation.so", kind);
357#else
358                    result.appendFormat("/system/lib/egl/lib%s_emulation.so", kind);
359#endif
360                    return result;
361                default:
362                    // Not in emulator, or use other guest-side implementation
363                    break;
364            }
365
366            String8 pattern;
367            pattern.appendFormat("lib%s", kind);
368            const char* const searchPaths[] = {
369#if defined(__LP64__)
370                    "/vendor/lib64/egl",
371                    "/system/lib64/egl"
372#else
373                    "/vendor/lib/egl",
374                    "/system/lib/egl"
375#endif
376            };
377
378            // first, we search for the exact name of the GLES userspace
379            // driver in both locations.
380            // i.e.:
381            //      libGLES.so, or:
382            //      libEGL.so, libGLESv1_CM.so, libGLESv2.so
383
384            for (size_t i=0 ; i<NELEM(searchPaths) ; i++) {
385                if (find(result, pattern, searchPaths[i], true)) {
386                    return result;
387                }
388            }
389
390            // for compatibility with the old "egl.cfg" naming convention
391            // we look for files that match:
392            //      libGLES_*.so, or:
393            //      libEGL_*.so, libGLESv1_CM_*.so, libGLESv2_*.so
394
395            pattern.append("_");
396            for (size_t i=0 ; i<NELEM(searchPaths) ; i++) {
397                if (find(result, pattern, searchPaths[i], false)) {
398                    return result;
399                }
400            }
401
402            // we didn't find the driver. gah.
403            result.clear();
404            return result;
405        }
406
407    private:
408        static bool find(String8& result,
409                const String8& pattern, const char* const search, bool exact) {
410            if (exact) {
411                String8 absolutePath;
412                absolutePath.appendFormat("%s/%s.so", search, pattern.string());
413                if (!access(absolutePath.string(), R_OK)) {
414                    result = absolutePath;
415                    return true;
416                }
417                return false;
418            }
419
420            DIR* d = opendir(search);
421            if (d != NULL) {
422                struct dirent cur;
423                struct dirent* e;
424                while (readdir_r(d, &cur, &e) == 0 && e) {
425                    if (e->d_type == DT_DIR) {
426                        continue;
427                    }
428                    if (!strcmp(e->d_name, "libGLES_android.so")) {
429                        // always skip the software renderer
430                        continue;
431                    }
432                    if (strstr(e->d_name, pattern.string()) == e->d_name) {
433                        if (!strcmp(e->d_name + strlen(e->d_name) - 3, ".so")) {
434                            result.clear();
435                            result.appendFormat("%s/%s", search, e->d_name);
436                            closedir(d);
437                            return true;
438                        }
439                    }
440                }
441                closedir(d);
442            }
443            return false;
444        }
445    };
446
447
448    String8 absolutePath = MatchFile::find(kind);
449    if (absolutePath.isEmpty()) {
450        // this happens often, we don't want to log an error
451        return 0;
452    }
453    const char* const driver_absolute_path = absolutePath.string();
454
455    void* dso = do_dlopen(driver_absolute_path, RTLD_NOW | RTLD_LOCAL);
456    if (dso == 0) {
457        const char* err = dlerror();
458        ALOGE("load_driver(%s): %s", driver_absolute_path, err?err:"unknown");
459        return 0;
460    }
461
462    ALOGD("loaded %s", driver_absolute_path);
463
464    return dso;
465}
466
467static void* do_android_dlopen_ext(const char* path, int mode, const android_dlextinfo* info) {
468    ATRACE_CALL();
469    return android_dlopen_ext(path, mode, info);
470}
471
472static const std::array<const char*, 2> HAL_SUBNAME_KEY_PROPERTIES = {{
473    "ro.hardware.egl",
474    "ro.board.platform",
475}};
476
477static void* load_updated_driver(const char* kind, android_namespace_t* ns) {
478    ATRACE_CALL();
479    const android_dlextinfo dlextinfo = {
480        .flags = ANDROID_DLEXT_USE_NAMESPACE,
481        .library_namespace = ns,
482    };
483    void* so = nullptr;
484    char prop[PROPERTY_VALUE_MAX + 1];
485    for (auto key : HAL_SUBNAME_KEY_PROPERTIES) {
486        if (property_get(key, prop, nullptr) > 0) {
487            String8 name;
488            name.appendFormat("lib%s_%s.so", kind, prop);
489            so = do_android_dlopen_ext(name.string(), RTLD_LOCAL | RTLD_NOW,
490                    &dlextinfo);
491            if (so)
492                return so;
493        }
494    }
495    return nullptr;
496}
497
498void *Loader::load_driver(const char* kind,
499        egl_connection_t* cnx, uint32_t mask)
500{
501    ATRACE_CALL();
502
503    void* dso = nullptr;
504    if (mGetDriverNamespace) {
505        android_namespace_t* ns = mGetDriverNamespace();
506        if (ns) {
507            dso = load_updated_driver(kind, ns);
508        }
509    }
510    if (!dso) {
511        dso = load_system_driver(kind);
512        if (!dso)
513            return NULL;
514    }
515
516    if (mask & EGL) {
517        getProcAddress = (getProcAddressType)dlsym(dso, "eglGetProcAddress");
518
519        ALOGE_IF(!getProcAddress,
520                "can't find eglGetProcAddress() in EGL driver library");
521
522        egl_t* egl = &cnx->egl;
523        __eglMustCastToProperFunctionPointerType* curr =
524            (__eglMustCastToProperFunctionPointerType*)egl;
525        char const * const * api = egl_names;
526        while (*api) {
527            char const * name = *api;
528            __eglMustCastToProperFunctionPointerType f =
529                (__eglMustCastToProperFunctionPointerType)dlsym(dso, name);
530            if (f == NULL) {
531                // couldn't find the entry-point, use eglGetProcAddress()
532                f = getProcAddress(name);
533                if (f == NULL) {
534                    f = (__eglMustCastToProperFunctionPointerType)0;
535                }
536            }
537            *curr++ = f;
538            api++;
539        }
540    }
541
542    if (mask & GLESv1_CM) {
543        init_api(dso, gl_names,
544            (__eglMustCastToProperFunctionPointerType*)
545                &cnx->hooks[egl_connection_t::GLESv1_INDEX]->gl,
546            getProcAddress);
547    }
548
549    if (mask & GLESv2) {
550      init_api(dso, gl_names,
551            (__eglMustCastToProperFunctionPointerType*)
552                &cnx->hooks[egl_connection_t::GLESv2_INDEX]->gl,
553            getProcAddress);
554    }
555
556    return dso;
557}
558
559// ----------------------------------------------------------------------------
560}; // namespace android
561// ----------------------------------------------------------------------------
562