C++ (Cpp) sdf_extension_create Examples

Example #1

void *sdf_extension_load(sdf_file_t *h)
{
    sdf_extension_create_t *sdf_extension_create;
    void *p;

    h->sdf_extension_version  = SDF_EXTENSION_VERSION;
    h->sdf_extension_revision = SDF_EXTENSION_REVISION;

    if (sdf_global_extension_failed) {
        h->error_message = "sdf_extension_load: failed to load extension.";
        return NULL;
    }

    if (sdf_global_extension) return sdf_global_extension;

    sdf_global_extension_dlhandle = dlopen("sdf_extension.so", RTLD_LAZY);

    if (!sdf_global_extension_dlhandle) {
        sdf_global_extension_failed = 1;
        h->error_message = dlerror();
        return NULL;
    }

    // Weird pointer copying required by ISO C
    p = dlsym(sdf_global_extension_dlhandle, "sdf_extension_create");
    memcpy(&sdf_extension_create, &p, sizeof(p));

    sdf_global_extension = sdf_extension_create(h);

    return sdf_global_extension;
}

Example #2

File: sdf_extension_util.c Project: keithbennett/SDF_C

void *sdf_extension_load(sdf_file_t *h)
{
#ifndef _WIN32
    sdf_extension_create_t *sdf_extension_create;
    void *p;
    char *libname1 = "sdf_extension.so";
    char *libname2 = "libsdf_extension.so";
    char *path_env, *pathname, *path;
    char *sep = ":;,";
    int len;
    struct stat sb;

    h->sdf_extension_version  = SDF_EXTENSION_VERSION;
    h->sdf_extension_revision = SDF_EXTENSION_REVISION;

    if (sdf_global_extension_failed) {
        h->error_message = "sdf_extension_load: failed to load extension.";
        return NULL;
    }

    if (sdf_global_extension) return sdf_global_extension;

    /*
     * SDF_EXTENSION_PATH is a string separated by colon, semicolon or comma
     * Each substring is examined in turn. If it is a file then we attempt to
     * load it as a dynamic library. If it is a directory then we attempt to
     * load a file named "sdf_extension.so" or "libsdf_extension.so" in that
     * directory. The routine exits once a valid library is found.
     */
    path_env = getenv("SDF_EXTENSION_PATH");
    if (path_env) {
        len = strlen(path_env) + strlen(libname1) + strlen(libname2) + 2;
        pathname = malloc(len);
        for (path = strtok(path_env, sep); path; path = strtok(NULL, sep)) {
            stat(path, &sb);
            if (S_ISDIR(sb.st_mode)) {
                snprintf(pathname, len, "%s/%s", path, libname1);
                sdf_global_extension_dlhandle = dlopen(pathname, RTLD_LAZY);
                if (!sdf_global_extension_dlhandle) {
                    snprintf(pathname, len, "%s/%s", path, libname2);
                    sdf_global_extension_dlhandle = dlopen(pathname, RTLD_LAZY);
                }
            } else if (S_ISREG(sb.st_mode)) {
                sdf_global_extension_dlhandle = dlopen(path, RTLD_LAZY);
            }
            if (sdf_global_extension_dlhandle) break;
        }
        free(pathname);
    }

    if (!sdf_global_extension_dlhandle) {
        sdf_global_extension_dlhandle = dlopen(libname1, RTLD_LAZY);
        if (!sdf_global_extension_dlhandle)
            sdf_global_extension_dlhandle = dlopen(libname2, RTLD_LAZY);
    }

    if (!sdf_global_extension_dlhandle) {
        sdf_global_extension_failed = 1;
        h->error_message = dlerror();
        return NULL;
    }

    // Weird pointer copying required by ISO C
    p = dlsym(sdf_global_extension_dlhandle, "sdf_extension_create");
    memcpy(&sdf_extension_create, &p, sizeof(p));

    sdf_global_extension = sdf_extension_create(h);

    return sdf_global_extension;
#endif
}