test

static int load(const char *id,        const char *path,        const struct hw_module_t **pHmi){    int status;    void *handle;    struct hw_module_t *hmi;    /*     * load the symbols resolving undefined symbols before     * dlopen returns. Since RTLD_GLOBAL is not or'd in with     * RTLD_NOW the external symbols will not be global     */    handle = dlopen(path, RTLD_NOW);    if (handle == NULL) {        char const *err_str = dlerror();        ALOGE("load: module=%s\n%s", path, err_str?err_str:"unknown");        status = -EINVAL;        goto done;    }    /* Get the address of the struct hal_module_info. */    const char *sym = HAL_MODULE_INFO_SYM_AS_STR;    hmi = (struct hw_module_t *)dlsym(handle, sym);    if (hmi == NULL) {        ALOGE("load: couldn't find symbol %s", sym);        status = -EINVAL;        goto done;    }    /* Check that the id matches */    if (strcmp(id, hmi->id) != 0) {        ALOGE("load: id=%s != hmi->id=%s", id, hmi->id);        status = -EINVAL;        goto done;    }    hmi->dso = handle;    /* success */    status = 0;    done:    if (status != 0) {        hmi = NULL;        if (handle != NULL) {            dlclose(handle);            handle = NULL;        }    } else {        ALOGV("loaded HAL id=%s path=%s hmi=%p handle=%p",                id, path, *pHmi, handle);    }    *pHmi = hmi;    return status;}

</pre><pre name="code" class="cpp">/** Base path of the hal modules */#if defined(__LP64__)#define HAL_LIBRARY_PATH1 "/system/lib64/hw"#define HAL_LIBRARY_PATH2 "/vendor/lib64/hw"#else#define HAL_LIBRARY_PATH1 "/system/lib/hw"#define HAL_LIBRARY_PATH2 "/vendor/lib/hw"#endif/** * There are a set of variant filename for modules. The form of the filename * is "<MODULE_ID>.variant.so" so for the led module the Dream variants  * of base "ro.product.board", "ro.board.platform" and "ro.arch" would be: * * led.trout.so * led.msm7k.so * led.ARMV6.so * led.default.so */static const char *variant_keys[] = {    "ro.hardware",  /* This goes first so that it can pick up a different                       file on the emulator. */    "ro.product.board",    "ro.board.platform",    "ro.arch"};static const int HAL_VARIANT_KEYS_COUNT =    (sizeof(variant_keys)/sizeof(variant_keys[0]));....../* * Check if a HAL with given name and subname exists, if so return 0, otherwise * otherwise return negative.  On success path will contain the path to the HAL. */static int hw_module_exists(char *path, size_t path_len, const char *name,                            const char *subname){    snprintf(path, path_len, "%s/%s.%s.so",             HAL_LIBRARY_PATH2, name, subname);    if (access(path, R_OK) == 0)        return 0;    snprintf(path, path_len, "%s/%s.%s.so",             HAL_LIBRARY_PATH1, name, subname);    if (access(path, R_OK) == 0)        return 0;    return -ENOENT;}int hw_get_module_by_class(const char *class_id, const char *inst,                           const struct hw_module_t **module){    int i;    char prop[PATH_MAX];    char path[PATH_MAX];    char name[PATH_MAX];    char prop_name[PATH_MAX];    if (inst)        snprintf(name, PATH_MAX, "%s.%s", class_id, inst);    else        strlcpy(name, class_id, PATH_MAX);    /*     * Here we rely on the fact that calling dlopen multiple times on     * the same .so will simply increment a refcount (and not load     * a new copy of the library).     * We also assume that dlopen() is thread-safe.     */    /* First try a property specific to the class and possibly instance */    snprintf(prop_name, sizeof(prop_name), "ro.hardware.%s", name);    if (property_get(prop_name, prop, NULL) > 0) {        if (hw_module_exists(path, sizeof(path), name, prop) == 0) {            goto found;        }    }    /* Loop through the configuration variants looking for a module */    for (i=0 ; i<HAL_VARIANT_KEYS_COUNT; i++) {        if (property_get(variant_keys[i], prop, NULL) == 0) {            continue;        }        if (hw_module_exists(path, sizeof(path), name, prop) == 0) {            goto found;        }    }    /* Nothing found, try the default */    if (hw_module_exists(path, sizeof(path), name, "default") == 0) {        goto found;    }    return -ENOENT;found:    /* load the module, if this fails, we're doomed, and we should not try     * to load a different variant. */    return load(class_id, path, module);}int hw_get_module(const char *id, const struct hw_module_t **module){    return hw_get_module_by_class(id, NULL, module);}

</pre><p></p><p>这是test</p><p></p><pre name="code" class="cpp">/** Base path of the hal modules */#if defined(__LP64__)#define HAL_LIBRARY_PATH1 "/system/lib64/hw"#define HAL_LIBRARY_PATH2 "/vendor/lib64/hw"#else#define HAL_LIBRARY_PATH1 "/system/lib/hw"#define HAL_LIBRARY_PATH2 "/vendor/lib/hw"#endif/** * There are a set of variant filename for modules. The form of the filename * is "<MODULE_ID>.variant.so" so for the led module the Dream variants  * of base "ro.product.board", "ro.board.platform" and "ro.arch" would be: * * led.trout.so * led.msm7k.so * led.ARMV6.so * led.default.so */static const char *variant_keys[] = {    "ro.hardware",  /* This goes first so that it can pick up a different                       file on the emulator. */    "ro.product.board",    "ro.board.platform",    "ro.arch"};static const int HAL_VARIANT_KEYS_COUNT =    (sizeof(variant_keys)/sizeof(variant_keys[0]));

typedef struct hw_module_t {    uint32_t tag;    uint16_t module_api_version;#define version_major module_api_version       uint16_t hal_api_version;#define version_minor hal_api_version    /** Identifier of module */    const char *id;    /** Name of this module */    const char *name;    const char *author;    /** Modules methods */    struct hw_module_methods_t* methods;    void* dso;#ifdef __LP64__    uint64_t reserved[32-7];#else    uint32_t reserved[32-7];#endif} hw_module_t;

test

typedef struct hw_module_methods_t {    /** Open a specific device */    int (*open)(const struct hw_module_t* module, const char* id,            struct hw_device_t** device);} hw_module_methods_t;

test

typedef struct hw_device_t {    uint32_t tag;    uint32_t version;    /** reference to the module this device belongs to */    struct hw_module_t* module;#ifdef __LP64__    uint64_t reserved[12];#else    uint32_t reserved[12];#endif    /** Close this device */    int (*close)(struct hw_device_t* device);} hw_device_t;

struct fb_context_t {    framebuffer_device_t  device;};......int fb_device_open(hw_module_t const* module, const char* name,        hw_device_t** device){    int status = -EINVAL;    if (!strcmp(name, GRALLOC_HARDWARE_FB0)) {        /* initialize our state here */        fb_context_t *dev = (fb_context_t*)malloc(sizeof(*dev));        memset(dev, 0, sizeof(*dev));        /* initialize the procs */        dev->device.common.tag = HARDWARE_DEVICE_TAG;        dev->device.common.version = 0;        dev->device.common.module = const_cast<hw_module_t*>(module);        dev->device.common.close = fb_close;        dev->device.setSwapInterval = fb_setSwapInterval;        dev->device.post            = fb_post;        dev->device.setUpdateRect = 0;        private_module_t* m = (private_module_t*)module;        status = mapFrameBuffer(m);        if (status >= 0) {            int stride = m->finfo.line_length / (m->info.bits_per_pixel >> 3);            int format = (m->info.bits_per_pixel == 32)                         ? (m->info.red.offset ? HAL_PIXEL_FORMAT_BGRA_8888 : HAL_PIXEL_FORMAT_RGBX_8888)                         : HAL_PIXEL_FORMAT_RGB_565;            const_cast<uint32_t&>(dev->device.flags) = 0;            const_cast<uint32_t&>(dev->device.width) = m->info.xres;            const_cast<uint32_t&>(dev->device.height) = m->info.yres;            const_cast<int&>(dev->device.stride) = stride;            const_cast<int&>(dev->device.format) = format;            const_cast<float&>(dev->device.xdpi) = m->xdpi;            const_cast<float&>(dev->device.ydpi) = m->ydpi;            const_cast<float&>(dev->device.fps) = m->fps;            const_cast<int&>(dev->device.minSwapInterval) = 1;            const_cast<int&>(dev->device.maxSwapInterval) = 1;            *device = &dev->device.common;        }    }    return status;}