Loader.cpp revision 48d438d05f14c2f4bd83ae89f520368cd49122df 
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
25#include <cutils/log.h>
26#include <cutils/properties.h>
27
28#include <EGL/egl.h>
29
30#include "egldefs.h"
31#include "glestrace.h"
32#include "hooks.h"
33#include "Loader.h"
34
35// ----------------------------------------------------------------------------
36namespace android {
37// ----------------------------------------------------------------------------
38
39
40/*
41 * EGL drivers are called
42 *
43 * /system/lib/egl/lib{[EGL|GLESv1_CM|GLESv2] | GLES}_$TAG.so
44 *
45 */
46
47ANDROID_SINGLETON_STATIC_INSTANCE( Loader )
48
49/* This function is called to check whether we run inside the emulator,
50 * and if this is the case whether GLES GPU emulation is supported.
51 *
52 * Returned values are:
53 *  -1   -> not running inside the emulator
54 *   0   -> running inside the emulator, but GPU emulation not supported
55 *   1   -> running inside the emulator, GPU emulation is supported
56 *          through the "emulation" config.
57 */
58static int
59checkGlesEmulationStatus(void)
60{
61    /* We're going to check for the following kernel parameters:
62     *
63     *    qemu=1                      -> tells us that we run inside the emulator
64     *    android.qemu.gles=<number>  -> tells us the GLES GPU emulation status
65     *
66     * Note that we will return <number> if we find it. This let us support
67     * more additionnal emulation modes in the future.
68     */
69    char  prop[PROPERTY_VALUE_MAX];
70    int   result = -1;
71
72    /* First, check for qemu=1 */
73    property_get("ro.kernel.qemu",prop,"0");
74    if (atoi(prop) != 1)
75        return -1;
76
77    /* We are in the emulator, get GPU status value */
78    property_get("ro.kernel.qemu.gles",prop,"0");
79    return atoi(prop);
80}
81
82// ----------------------------------------------------------------------------
83
84Loader::driver_t::driver_t(void* gles)
85{
86    dso[0] = gles;
87    for (size_t i=1 ; i<NELEM(dso) ; i++)
88        dso[i] = 0;
89}
90
91Loader::driver_t::~driver_t()
92{
93    for (size_t i=0 ; i<NELEM(dso) ; i++) {
94        if (dso[i]) {
95            dlclose(dso[i]);
96            dso[i] = 0;
97        }
98    }
99}
100
101status_t Loader::driver_t::set(void* hnd, int32_t api)
102{
103    switch (api) {
104        case EGL:
105            dso[0] = hnd;
106            break;
107        case GLESv1_CM:
108            dso[1] = hnd;
109            break;
110        case GLESv2:
111            dso[2] = hnd;
112            break;
113        default:
114            return BAD_INDEX;
115    }
116    return NO_ERROR;
117}
118
119// ----------------------------------------------------------------------------
120
121Loader::entry_t::entry_t(int dpy, int impl, const char* tag)
122    : dpy(dpy), impl(impl), tag(tag) {
123}
124
125// ----------------------------------------------------------------------------
126
127Loader::Loader()
128{
129    char line[256];
130    char tag[256];
131
132    /* Special case for GLES emulation */
133    if (checkGlesEmulationStatus() == 0) {
134        ALOGD("Emulator without GPU support detected. Fallback to software renderer.");
135        gConfig.add( entry_t(0, 0, "android") );
136        return;
137    }
138
139    /* Otherwise, use egl.cfg */
140    FILE* cfg = fopen("/system/lib/egl/egl.cfg", "r");
141    if (cfg == NULL) {
142        // default config
143        ALOGD("egl.cfg not found, using default config");
144        gConfig.add( entry_t(0, 0, "android") );
145    } else {
146        while (fgets(line, 256, cfg)) {
147            int dpy;
148            int impl;
149            if (sscanf(line, "%u %u %s", &dpy, &impl, tag) == 3) {
150                //ALOGD(">>> %u %u %s", dpy, impl, tag);
151                gConfig.add( entry_t(dpy, impl, tag) );
152            }
153        }
154        fclose(cfg);
155    }
156}
157
158Loader::~Loader()
159{
160    GLTrace_stop();
161}
162
163const char* Loader::getTag(int dpy, int impl)
164{
165    const Vector<entry_t>& cfgs(gConfig);
166    const size_t c = cfgs.size();
167    for (size_t i=0 ; i<c ; i++) {
168        if (dpy == cfgs[i].dpy)
169            if (impl == cfgs[i].impl)
170                return cfgs[i].tag.string();
171    }
172    return 0;
173}
174
175void* Loader::open(EGLNativeDisplayType display, int impl, egl_connection_t* cnx)
176{
177    /*
178     * TODO: if we don't find display/0, then use 0/0
179     * (0/0 should always work)
180     */
181
182    void* dso;
183    int index = int(display);
184    driver_t* hnd = 0;
185
186    char const* tag = getTag(index, impl);
187    if (tag) {
188        dso = load_driver("GLES", tag, cnx, EGL | GLESv1_CM | GLESv2);
189        if (dso) {
190            hnd = new driver_t(dso);
191        } else {
192            // Always load EGL first
193            dso = load_driver("EGL", tag, cnx, EGL);
194            if (dso) {
195                hnd = new driver_t(dso);
196
197                // TODO: make this more automated
198                hnd->set( load_driver("GLESv1_CM", tag, cnx, GLESv1_CM), GLESv1_CM );
199
200                hnd->set( load_driver("GLESv2", tag, cnx, GLESv2), GLESv2 );
201            }
202        }
203    }
204
205    LOG_FATAL_IF(!index && !impl && !hnd,
206            "couldn't find the default OpenGL ES implementation "
207            "for default display");
208
209    return (void*)hnd;
210}
211
212status_t Loader::close(void* driver)
213{
214    driver_t* hnd = (driver_t*)driver;
215    delete hnd;
216    return NO_ERROR;
217}
218
219void Loader::init_api(void* dso,
220        char const * const * api,
221        __eglMustCastToProperFunctionPointerType* curr,
222        getProcAddressType getProcAddress)
223{
224    const size_t SIZE = 256;
225    char scrap[SIZE];
226    while (*api) {
227        char const * name = *api;
228        __eglMustCastToProperFunctionPointerType f =
229            (__eglMustCastToProperFunctionPointerType)dlsym(dso, name);
230        if (f == NULL) {
231            // couldn't find the entry-point, use eglGetProcAddress()
232            f = getProcAddress(name);
233        }
234        if (f == NULL) {
235            // Try without the OES postfix
236            ssize_t index = ssize_t(strlen(name)) - 3;
237            if ((index>0 && (index<SIZE-1)) && (!strcmp(name+index, "OES"))) {
238                strncpy(scrap, name, index);
239                scrap[index] = 0;
240                f = (__eglMustCastToProperFunctionPointerType)dlsym(dso, scrap);
241                //ALOGD_IF(f, "found <%s> instead", scrap);
242            }
243        }
244        if (f == NULL) {
245            // Try with the OES postfix
246            ssize_t index = ssize_t(strlen(name)) - 3;
247            if (index>0 && strcmp(name+index, "OES")) {
248                snprintf(scrap, SIZE, "%sOES", name);
249                f = (__eglMustCastToProperFunctionPointerType)dlsym(dso, scrap);
250                //ALOGD_IF(f, "found <%s> instead", scrap);
251            }
252        }
253        if (f == NULL) {
254            //ALOGD("%s", name);
255            f = (__eglMustCastToProperFunctionPointerType)gl_unimplemented;
256
257            /*
258             * GL_EXT_debug_label is special, we always report it as
259             * supported, it's handled by GLES_trace. If GLES_trace is not
260             * enabled, then these are no-ops.
261             */
262            if (!strcmp(name, "glInsertEventMarkerEXT")) {
263                f = (__eglMustCastToProperFunctionPointerType)gl_noop;
264            } else if (!strcmp(name, "glPushGroupMarkerEXT")) {
265                f = (__eglMustCastToProperFunctionPointerType)gl_noop;
266            } else if (!strcmp(name, "glPopGroupMarkerEXT")) {
267                f = (__eglMustCastToProperFunctionPointerType)gl_noop;
268            }
269        }
270        *curr++ = f;
271        api++;
272    }
273}
274
275void *Loader::load_driver(const char* kind, const char *tag,
276        egl_connection_t* cnx, uint32_t mask)
277{
278    char driver_absolute_path[PATH_MAX];
279    const char* const search1 = "/vendor/lib/egl/lib%s_%s.so";
280    const char* const search2 = "/system/lib/egl/lib%s_%s.so";
281
282    snprintf(driver_absolute_path, PATH_MAX, search1, kind, tag);
283    if (access(driver_absolute_path, R_OK)) {
284        snprintf(driver_absolute_path, PATH_MAX, search2, kind, tag);
285        if (access(driver_absolute_path, R_OK)) {
286            // this happens often, we don't want to log an error
287            return 0;
288        }
289    }
290
291    void* dso = dlopen(driver_absolute_path, RTLD_NOW | RTLD_LOCAL);
292    if (dso == 0) {
293        const char* err = dlerror();
294        ALOGE("load_driver(%s): %s", driver_absolute_path, err?err:"unknown");
295        return 0;
296    }
297
298    ALOGD("loaded %s", driver_absolute_path);
299
300    if (mask & EGL) {
301        getProcAddress = (getProcAddressType)dlsym(dso, "eglGetProcAddress");
302
303        ALOGE_IF(!getProcAddress,
304                "can't find eglGetProcAddress() in %s", driver_absolute_path);
305
306        egl_t* egl = &cnx->egl;
307        __eglMustCastToProperFunctionPointerType* curr =
308            (__eglMustCastToProperFunctionPointerType*)egl;
309        char const * const * api = egl_names;
310        while (*api) {
311            char const * name = *api;
312            __eglMustCastToProperFunctionPointerType f =
313                (__eglMustCastToProperFunctionPointerType)dlsym(dso, name);
314            if (f == NULL) {
315                // couldn't find the entry-point, use eglGetProcAddress()
316                f = getProcAddress(name);
317                if (f == NULL) {
318                    f = (__eglMustCastToProperFunctionPointerType)0;
319                }
320            }
321            *curr++ = f;
322            api++;
323        }
324    }
325
326    if (mask & GLESv1_CM) {
327        init_api(dso, gl_names,
328            (__eglMustCastToProperFunctionPointerType*)
329                &cnx->hooks[GLESv1_INDEX]->gl,
330            getProcAddress);
331    }
332
333    if (mask & GLESv2) {
334      init_api(dso, gl_names,
335            (__eglMustCastToProperFunctionPointerType*)
336                &cnx->hooks[GLESv2_INDEX]->gl,
337            getProcAddress);
338    }
339
340    return dso;
341}
342
343// ----------------------------------------------------------------------------
344}; // namespace android
345// ----------------------------------------------------------------------------
346