Loader.cpp revision 69e5b1ab80018817b1d4ffbbdb5695ff70168c95 
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#include <ctype.h>
18#include <stdlib.h>
19#include <stdio.h>
20#include <string.h>
21#include <errno.h>
22#include <dlfcn.h>
23#include <limits.h>
24#include <dirent.h>
25
26#include <cutils/log.h>
27#include <cutils/properties.h>
28
29#include <EGL/egl.h>
30
31#include "egldefs.h"
32#include "Loader.h"
33
34// ----------------------------------------------------------------------------
35namespace android {
36// ----------------------------------------------------------------------------
37
38
39/*
40 * EGL userspace drivers must be provided either:
41 * - as a single library:
42 *      /vendor/lib/egl/libGLES.so
43 *
44 * - as separate libraries:
45 *      /vendor/lib/egl/libEGL.so
46 *      /vendor/lib/egl/libGLESv1_CM.so
47 *      /vendor/lib/egl/libGLESv2.so
48 *
49 * The software renderer for the emulator must be provided as a single
50 * library at:
51 *
52 *      /system/lib/egl/libGLES_android.so
53 *
54 *
55 * For backward compatibility and to facilitate the transition to
56 * this new naming scheme, the loader will additionally look for:
57 *
58 *      /{vendor|system}/lib/egl/lib{GLES | [EGL|GLESv1_CM|GLESv2]}_*.so
59 *
60 */
61
62ANDROID_SINGLETON_STATIC_INSTANCE( Loader )
63
64/* This function is called to check whether we run inside the emulator,
65 * and if this is the case whether GLES GPU emulation is supported.
66 *
67 * Returned values are:
68 *  -1   -> not running inside the emulator
69 *   0   -> running inside the emulator, but GPU emulation not supported
70 *   1   -> running inside the emulator, GPU emulation is supported
71 *          through the "emulation" host-side OpenGL ES implementation.
72 *   2   -> running inside the emulator, GPU emulation is supported
73 *          through a guest-side vendor driver's OpenGL ES implementation.
74 */
75static int
76checkGlesEmulationStatus(void)
77{
78    /* We're going to check for the following kernel parameters:
79     *
80     *    qemu=1                      -> tells us that we run inside the emulator
81     *    android.qemu.gles=<number>  -> tells us the GLES GPU emulation status
82     *
83     * Note that we will return <number> if we find it. This let us support
84     * more additionnal emulation modes in the future.
85     */
86    char  prop[PROPERTY_VALUE_MAX];
87    int   result = -1;
88
89    /* First, check for qemu=1 */
90    property_get("ro.kernel.qemu",prop,"0");
91    if (atoi(prop) != 1)
92        return -1;
93
94    /* We are in the emulator, get GPU status value */
95    property_get("qemu.gles",prop,"0");
96    return atoi(prop);
97}
98
99// ----------------------------------------------------------------------------
100
101static char const * getProcessCmdline() {
102    long pid = getpid();
103    char procPath[128];
104    snprintf(procPath, 128, "/proc/%ld/cmdline", pid);
105    FILE * file = fopen(procPath, "r");
106    if (file) {
107        static char cmdline[256];
108        char *str = fgets(cmdline, sizeof(cmdline) - 1, file);
109        fclose(file);
110        if (str) {
111            return cmdline;
112        }
113    }
114    return NULL;
115}
116
117// ----------------------------------------------------------------------------
118
119Loader::driver_t::driver_t(void* gles)
120{
121    dso[0] = gles;
122    for (size_t i=1 ; i<NELEM(dso) ; i++)
123        dso[i] = 0;
124}
125
126Loader::driver_t::~driver_t()
127{
128    for (size_t i=0 ; i<NELEM(dso) ; i++) {
129        if (dso[i]) {
130            dlclose(dso[i]);
131            dso[i] = 0;
132        }
133    }
134}
135
136status_t Loader::driver_t::set(void* hnd, int32_t api)
137{
138    switch (api) {
139        case EGL:
140            dso[0] = hnd;
141            break;
142        case GLESv1_CM:
143            dso[1] = hnd;
144            break;
145        case GLESv2:
146            dso[2] = hnd;
147            break;
148        default:
149            return BAD_INDEX;
150    }
151    return NO_ERROR;
152}
153
154// ----------------------------------------------------------------------------
155
156Loader::Loader()
157    : getProcAddress(NULL) {
158}
159
160Loader::~Loader() {
161}
162
163static void* load_wrapper(const char* path) {
164    void* so = dlopen(path, RTLD_NOW | RTLD_LOCAL);
165    ALOGE_IF(!so, "dlopen(\"%s\") failed: %s", path, dlerror());
166    return so;
167}
168
169#ifndef EGL_WRAPPER_DIR
170#if defined(__LP64__)
171#define EGL_WRAPPER_DIR "/system/lib64"
172#else
173#define EGL_WRAPPER_DIR "/system/lib"
174#endif
175#endif
176
177static void setEmulatorGlesValue(void) {
178    char prop[PROPERTY_VALUE_MAX];
179    property_get("ro.kernel.qemu", prop, "0");
180    if (atoi(prop) != 1) return;
181
182    property_get("ro.kernel.qemu.gles",prop,"0");
183    if (atoi(prop) == 1) {
184        ALOGD("Emulator has host GPU support, qemu.gles is set to 1.");
185        property_set("qemu.gles", "1");
186        return;
187    }
188
189    // for now, checking the following
190    // directory is good enough for emulator system images
191    const char* vendor_lib_path =
192#if defined(__LP64__)
193        "/vendor/lib64/egl";
194#else
195        "/vendor/lib/egl";
196#endif
197
198    const bool has_vendor_lib = (access(vendor_lib_path, R_OK) == 0);
199    if (has_vendor_lib) {
200        ALOGD("Emulator has vendor provided software renderer, qemu.gles is set to 2.");
201        property_set("qemu.gles", "2");
202    } else {
203        ALOGD("Emulator without GPU support detected. "
204              "Fallback to legacy software renderer, qemu.gles is set to 0.");
205        property_set("qemu.gles", "0");
206    }
207}
208
209void* Loader::open(egl_connection_t* cnx)
210{
211    void* dso;
212    driver_t* hnd = 0;
213
214    setEmulatorGlesValue();
215
216    dso = load_driver("GLES", cnx, EGL | GLESv1_CM | GLESv2);
217    if (dso) {
218        hnd = new driver_t(dso);
219    } else {
220        // Always load EGL first
221        dso = load_driver("EGL", cnx, EGL);
222        if (dso) {
223            hnd = new driver_t(dso);
224            hnd->set( load_driver("GLESv1_CM", cnx, GLESv1_CM), GLESv1_CM );
225            hnd->set( load_driver("GLESv2",    cnx, GLESv2),    GLESv2 );
226        }
227    }
228
229    LOG_ALWAYS_FATAL_IF(!hnd, "couldn't find an OpenGL ES implementation");
230
231    cnx->libEgl   = load_wrapper(EGL_WRAPPER_DIR "/libEGL.so");
232    cnx->libGles2 = load_wrapper(EGL_WRAPPER_DIR "/libGLESv2.so");
233    cnx->libGles1 = load_wrapper(EGL_WRAPPER_DIR "/libGLESv1_CM.so");
234
235    LOG_ALWAYS_FATAL_IF(!cnx->libEgl,
236            "couldn't load system EGL wrapper libraries");
237
238    LOG_ALWAYS_FATAL_IF(!cnx->libGles2 || !cnx->libGles1,
239            "couldn't load system OpenGL ES wrapper libraries");
240
241    return (void*)hnd;
242}
243
244status_t Loader::close(void* driver)
245{
246    driver_t* hnd = (driver_t*)driver;
247    delete hnd;
248    return NO_ERROR;
249}
250
251void Loader::init_api(void* dso,
252        char const * const * api,
253        __eglMustCastToProperFunctionPointerType* curr,
254        getProcAddressType getProcAddress)
255{
256    const ssize_t SIZE = 256;
257    char scrap[SIZE];
258    while (*api) {
259        char const * name = *api;
260        __eglMustCastToProperFunctionPointerType f =
261            (__eglMustCastToProperFunctionPointerType)dlsym(dso, name);
262        if (f == NULL) {
263            // couldn't find the entry-point, use eglGetProcAddress()
264            f = getProcAddress(name);
265        }
266        if (f == NULL) {
267            // Try without the OES postfix
268            ssize_t index = ssize_t(strlen(name)) - 3;
269            if ((index>0 && (index<SIZE-1)) && (!strcmp(name+index, "OES"))) {
270                strncpy(scrap, name, index);
271                scrap[index] = 0;
272                f = (__eglMustCastToProperFunctionPointerType)dlsym(dso, scrap);
273                //ALOGD_IF(f, "found <%s> instead", scrap);
274            }
275        }
276        if (f == NULL) {
277            // Try with the OES postfix
278            ssize_t index = ssize_t(strlen(name)) - 3;
279            if (index>0 && strcmp(name+index, "OES")) {
280                snprintf(scrap, SIZE, "%sOES", name);
281                f = (__eglMustCastToProperFunctionPointerType)dlsym(dso, scrap);
282                //ALOGD_IF(f, "found <%s> instead", scrap);
283            }
284        }
285        if (f == NULL) {
286            //ALOGD("%s", name);
287            f = (__eglMustCastToProperFunctionPointerType)gl_unimplemented;
288
289            /*
290             * GL_EXT_debug_label is special, we always report it as
291             * supported, it's handled by GLES_trace. If GLES_trace is not
292             * enabled, then these are no-ops.
293             */
294            if (!strcmp(name, "glInsertEventMarkerEXT")) {
295                f = (__eglMustCastToProperFunctionPointerType)gl_noop;
296            } else if (!strcmp(name, "glPushGroupMarkerEXT")) {
297                f = (__eglMustCastToProperFunctionPointerType)gl_noop;
298            } else if (!strcmp(name, "glPopGroupMarkerEXT")) {
299                f = (__eglMustCastToProperFunctionPointerType)gl_noop;
300            }
301        }
302        *curr++ = f;
303        api++;
304    }
305}
306
307void *Loader::load_driver(const char* kind,
308        egl_connection_t* cnx, uint32_t mask)
309{
310    class MatchFile {
311    public:
312        static String8 find(const char* kind) {
313            String8 result;
314            int emulationStatus = checkGlesEmulationStatus();
315            switch (emulationStatus) {
316                case 0:
317#if defined(__LP64__)
318                    result.setTo("/system/lib64/egl/libGLES_android.so");
319#else
320                    result.setTo("/system/lib/egl/libGLES_android.so");
321#endif
322                    return result;
323                case 1:
324                    // Use host-side OpenGL through the "emulation" library
325#if defined(__LP64__)
326                    result.appendFormat("/system/lib64/egl/lib%s_emulation.so", kind);
327#else
328                    result.appendFormat("/system/lib/egl/lib%s_emulation.so", kind);
329#endif
330                    return result;
331                default:
332                    // Not in emulator, or use other guest-side implementation
333                    break;
334            }
335
336            String8 pattern;
337            pattern.appendFormat("lib%s", kind);
338            const char* const searchPaths[] = {
339#if defined(__LP64__)
340                    "/vendor/lib64/egl",
341                    "/system/lib64/egl"
342#else
343                    "/vendor/lib/egl",
344                    "/system/lib/egl"
345#endif
346            };
347
348            // first, we search for the exact name of the GLES userspace
349            // driver in both locations.
350            // i.e.:
351            //      libGLES.so, or:
352            //      libEGL.so, libGLESv1_CM.so, libGLESv2.so
353
354            for (size_t i=0 ; i<NELEM(searchPaths) ; i++) {
355                if (find(result, pattern, searchPaths[i], true)) {
356                    return result;
357                }
358            }
359
360            // for compatibility with the old "egl.cfg" naming convention
361            // we look for files that match:
362            //      libGLES_*.so, or:
363            //      libEGL_*.so, libGLESv1_CM_*.so, libGLESv2_*.so
364
365            pattern.append("_");
366            for (size_t i=0 ; i<NELEM(searchPaths) ; i++) {
367                if (find(result, pattern, searchPaths[i], false)) {
368                    return result;
369                }
370            }
371
372            // we didn't find the driver. gah.
373            result.clear();
374            return result;
375        }
376
377    private:
378        static bool find(String8& result,
379                const String8& pattern, const char* const search, bool exact) {
380            if (exact) {
381                String8 absolutePath;
382                absolutePath.appendFormat("%s/%s.so", search, pattern.string());
383                if (!access(absolutePath.string(), R_OK)) {
384                    result = absolutePath;
385                    return true;
386                }
387                return false;
388            }
389
390            DIR* d = opendir(search);
391            if (d != NULL) {
392                struct dirent cur;
393                struct dirent* e;
394                while (readdir_r(d, &cur, &e) == 0 && e) {
395                    if (e->d_type == DT_DIR) {
396                        continue;
397                    }
398                    if (!strcmp(e->d_name, "libGLES_android.so")) {
399                        // always skip the software renderer
400                        continue;
401                    }
402                    if (strstr(e->d_name, pattern.string()) == e->d_name) {
403                        if (!strcmp(e->d_name + strlen(e->d_name) - 3, ".so")) {
404                            result.clear();
405                            result.appendFormat("%s/%s", search, e->d_name);
406                            closedir(d);
407                            return true;
408                        }
409                    }
410                }
411                closedir(d);
412            }
413            return false;
414        }
415    };
416
417
418    String8 absolutePath = MatchFile::find(kind);
419    if (absolutePath.isEmpty()) {
420        // this happens often, we don't want to log an error
421        return 0;
422    }
423    const char* const driver_absolute_path = absolutePath.string();
424
425    void* dso = dlopen(driver_absolute_path, RTLD_NOW | RTLD_LOCAL);
426    if (dso == 0) {
427        const char* err = dlerror();
428        ALOGE("load_driver(%s): %s", driver_absolute_path, err?err:"unknown");
429        return 0;
430    }
431
432    ALOGD("loaded %s", driver_absolute_path);
433
434    if (mask & EGL) {
435        getProcAddress = (getProcAddressType)dlsym(dso, "eglGetProcAddress");
436
437        ALOGE_IF(!getProcAddress,
438                "can't find eglGetProcAddress() in %s", driver_absolute_path);
439
440        egl_t* egl = &cnx->egl;
441        __eglMustCastToProperFunctionPointerType* curr =
442            (__eglMustCastToProperFunctionPointerType*)egl;
443        char const * const * api = egl_names;
444        while (*api) {
445            char const * name = *api;
446            __eglMustCastToProperFunctionPointerType f =
447                (__eglMustCastToProperFunctionPointerType)dlsym(dso, name);
448            if (f == NULL) {
449                // couldn't find the entry-point, use eglGetProcAddress()
450                f = getProcAddress(name);
451                if (f == NULL) {
452                    f = (__eglMustCastToProperFunctionPointerType)0;
453                }
454            }
455            *curr++ = f;
456            api++;
457        }
458    }
459
460    if (mask & GLESv1_CM) {
461        init_api(dso, gl_names,
462            (__eglMustCastToProperFunctionPointerType*)
463                &cnx->hooks[egl_connection_t::GLESv1_INDEX]->gl,
464            getProcAddress);
465    }
466
467    if (mask & GLESv2) {
468      init_api(dso, gl_names,
469            (__eglMustCastToProperFunctionPointerType*)
470                &cnx->hooks[egl_connection_t::GLESv2_INDEX]->gl,
471            getProcAddress);
472    }
473
474    return dso;
475}
476
477// ----------------------------------------------------------------------------
478}; // namespace android
479// ----------------------------------------------------------------------------
480