| 1 | #include <assert.h> |
| 2 | #include <errno.h> |
| 3 | #include <inttypes.h> |
| 4 | #include <stdint.h> |
| 5 | #include <stdio.h> |
| 6 | #include <stdlib.h> |
| 7 | #include <string.h> |
| 8 | |
| 9 | #include <jni.h> |
| 10 | |
| 11 | #include <sys/types.h> |
| 12 | #include <sys/socket.h> |
| 13 | #include <sys/un.h> |
| 14 | #include <unistd.h> |
| 15 | |
| 16 | #undef sun |
| 17 | |
| 18 | union align { |
| 19 | int i; |
| 20 | long l; |
| 21 | double d; |
| 22 | void *p; |
| 23 | void (*f)(void *); |
| 24 | struct notexist *s; |
| 25 | }; |
| 26 | |
| 27 | struct native_type { |
| 28 | const char *name; |
| 29 | size_t sz; |
| 30 | uint32_t tag; |
| 31 | }; |
| 32 | |
| 33 | typedef jbyteArray wrapped; |
| 34 | |
| 35 | struct open { |
| 36 | wrapped obj; |
| 37 | jbyte *arr; |
| 38 | }; |
| 39 | |
| 40 | struct base { |
| 41 | uint32_t tag; |
| 42 | }; |
| 43 | |
| 44 | static void except(JNIEnv *jni, const char *clsname, const char *msg) |
| 45 | { |
| 46 | jclass cls; |
| 47 | int rc; |
| 48 | |
| 49 | cls = (*jni)->FindClass(jni, clsname); assert(cls); |
| 50 | rc = (*jni)->ThrowNew(jni, cls, msg); assert(!rc); |
| 51 | } |
| 52 | |
| 53 | static void except_errno(JNIEnv *jni, const char *clsname, int err) |
| 54 | { except(jni, clsname, strerror(err)); } |
| 55 | |
| 56 | static void *open_struct_unchecked(JNIEnv *jni, wrapped obj, struct open *op) |
| 57 | { |
| 58 | jboolean copyp; |
| 59 | uintptr_t p, q; |
| 60 | |
| 61 | op->obj = obj; |
| 62 | op->arr = (*jni)->GetByteArrayElements(jni, obj, ©p); |
| 63 | if (!op->arr) return (0); |
| 64 | p = (uintptr_t)op->arr; |
| 65 | q = p + sizeof(union align) - 1; |
| 66 | q -= q%sizeof(union align); |
| 67 | fprintf(stderr, ";; offset = %"PRIuPTR"\n", q - p); |
| 68 | return (op->arr + (q - p)); |
| 69 | } |
| 70 | |
| 71 | static void *open_struct(JNIEnv *jni, wrapped obj, |
| 72 | const struct native_type *ty, struct open *op) |
| 73 | { |
| 74 | struct base *p; |
| 75 | jsize n; |
| 76 | |
| 77 | if (!obj) { except(jni, "java/lang/NullPointerException", 0); return (0); } |
| 78 | n = (*jni)->GetArrayLength(jni, obj); |
| 79 | if ((*jni)->ExceptionOccurred(jni)) return (0); |
| 80 | p = open_struct_unchecked(jni, obj, op); |
| 81 | if (!p) return (0); |
| 82 | if (n < ty->sz + sizeof(union align) - 1 || p->tag != ty->tag) |
| 83 | { |
| 84 | (*jni)->ReleaseByteArrayElements(jni, obj, op->arr, JNI_ABORT); |
| 85 | except(jni, "uk/org/distorted/tripe/JNI$NativeObjectTypeException", 0); |
| 86 | return (0); |
| 87 | } |
| 88 | return (p); |
| 89 | } |
| 90 | |
| 91 | static wrapped close_struct(JNIEnv *jni, struct open *op) |
| 92 | { |
| 93 | (*jni)->ReleaseByteArrayElements(jni, op->obj, op->arr, 0); |
| 94 | return (op->obj); |
| 95 | } |
| 96 | |
| 97 | static void *alloc_struct(JNIEnv *jni, const struct native_type *ty, |
| 98 | struct open *op) |
| 99 | { |
| 100 | wrapped obj; |
| 101 | struct base *p; |
| 102 | |
| 103 | obj = (*jni)->NewByteArray(jni, ty->sz + sizeof(union align) - 1); |
| 104 | if (!obj) return (0); |
| 105 | p = open_struct_unchecked(jni, obj, op); |
| 106 | if (!p) { (*jni)->DeleteLocalRef(jni, obj); return (0); } |
| 107 | p->tag = ty->tag; |
| 108 | return (p); |
| 109 | } |
| 110 | |
| 111 | JNIEXPORT void JNICALL Java_uk_org_distorted_tripe_JNI_test |
| 112 | (JNIEnv *jni, jobject cls) |
| 113 | { printf("Hello from C!\n"); } |
| 114 | |
| 115 | struct toy { |
| 116 | struct base _base; |
| 117 | const char *p; |
| 118 | }; |
| 119 | static const struct native_type toy_type = |
| 120 | { "toy", sizeof(struct toy), 0x58008918 }; |
| 121 | |
| 122 | JNIEXPORT wrapped JNICALL Java_uk_org_distorted_tripe_JNI_make |
| 123 | (JNIEnv *jni, jobject cls) |
| 124 | { |
| 125 | struct open op_toy; |
| 126 | struct toy *toy; |
| 127 | |
| 128 | toy = alloc_struct(jni, &toy_type, &op_toy); |
| 129 | if (!toy) return (0); |
| 130 | toy->p = "A working thing"; |
| 131 | return (close_struct(jni, &op_toy)); |
| 132 | } |
| 133 | |
| 134 | JNIEXPORT void JNICALL Java_uk_org_distorted_tripe_JNI_check |
| 135 | (JNIEnv *jni, jobject cls, wrapped wtoy) |
| 136 | { |
| 137 | struct toy *toy; |
| 138 | struct open op_toy; |
| 139 | |
| 140 | toy = open_struct(jni, wtoy, &toy_type, &op_toy); |
| 141 | if (!toy) return; |
| 142 | printf("Toy says: %s\n", toy->p); |
| 143 | close_struct(jni, &op_toy); |
| 144 | } |
| 145 | |
| 146 | struct conn { |
| 147 | struct base _base; |
| 148 | int fd; |
| 149 | unsigned f; |
| 150 | #define CF_CLOSERD 1u |
| 151 | #define CF_CLOSEWR 2u |
| 152 | #define CF_CLOSEMASK (CF_CLOSERD | CF_CLOSEWR) |
| 153 | }; |
| 154 | static const struct native_type conn_type |
| 155 | = { "conn", sizeof(struct conn), 0xed030167 }; |
| 156 | |
| 157 | JNIEXPORT wrapped JNICALL Java_uk_org_distorted_tripe_JNI_connect |
| 158 | (JNIEnv *jni, jobject cls) |
| 159 | { |
| 160 | struct conn *conn; |
| 161 | struct open op; |
| 162 | struct sockaddr_un sun; |
| 163 | int fd = -1; |
| 164 | |
| 165 | conn = alloc_struct(jni, &conn_type, &op); |
| 166 | if (!conn) goto err; |
| 167 | |
| 168 | fd = socket(SOCK_STREAM, PF_UNIX, 0); |
| 169 | if (!fd) goto err_except; |
| 170 | |
| 171 | sun.sun_family = AF_UNIX; |
| 172 | strcpy(sun.sun_path, "/tmp/mdw/sk"); |
| 173 | if (connect(fd, (struct sockaddr *)&sun, sizeof(sun))) goto err_except; |
| 174 | |
| 175 | conn->fd = fd; |
| 176 | return (close_struct(jni, &op)); |
| 177 | |
| 178 | err_except: |
| 179 | except_errno(jni, "java/io/IOException", errno); |
| 180 | err: |
| 181 | if (fd) close(fd); |
| 182 | return (0); |
| 183 | } |
| 184 | |
| 185 | JNIEXPORT void JNICALL Java_uk_org_distorted_tripe_JNI_send |
| 186 | (JNIEnv *jni, jobject cls, wrapped wconn, jbyteArray buf, |
| 187 | jint start, jint len) |
| 188 | { |
| 189 | struct conn *conn = 0; |
| 190 | struct open op; |
| 191 | jboolean copyp; |
| 192 | jsize bufsz; |
| 193 | ssize_t n; |
| 194 | jbyte *p = 0; |
| 195 | |
| 196 | conn = open_struct(jni, wconn, &conn_type, &op); |
| 197 | if (!conn) goto end; |
| 198 | |
| 199 | bufsz = (*jni)->GetArrayLength(jni, buf); |
| 200 | if ((*jni)->ExceptionOccurred(jni)) goto end; |
| 201 | if (bufsz < start || bufsz - start < len) { |
| 202 | except(jni, "java/lang/IndexOutOfBoundsException", |
| 203 | "bad send-buffer bounds"); |
| 204 | goto end; |
| 205 | } |
| 206 | |
| 207 | p = (*jni)->GetByteArrayElements(jni, buf, ©p); |
| 208 | if (!p) goto end; |
| 209 | |
| 210 | while (len) { |
| 211 | n = send(conn->fd, p + start, len, 0); |
| 212 | if (n < 0) { |
| 213 | except_errno(jni, "java/io/IOException", errno); |
| 214 | goto end; |
| 215 | } |
| 216 | start += n; len -= n; |
| 217 | } |
| 218 | |
| 219 | end: |
| 220 | if (p) (*jni)->ReleaseByteArrayElements(jni, buf, p, JNI_ABORT); |
| 221 | if (conn) close_struct(jni, &op); |
| 222 | return; |
| 223 | } |
| 224 | |
| 225 | JNIEXPORT jint JNICALL Java_uk_org_distorted_tripe_JNI_recv |
| 226 | (JNIEnv *jni, jobject cls, wrapped wconn, jbyteArray buf, |
| 227 | jint start, jint len) |
| 228 | { |
| 229 | struct conn *conn = 0; |
| 230 | struct open op; |
| 231 | jboolean copyp; |
| 232 | jsize bufsz; |
| 233 | jbyte *p = 0; |
| 234 | jint rc = -1; |
| 235 | |
| 236 | conn = open_struct(jni, wconn, &conn_type, &op); |
| 237 | if (!conn) goto end; |
| 238 | |
| 239 | bufsz = (*jni)->GetArrayLength(jni, buf); |
| 240 | if ((*jni)->ExceptionOccurred(jni)) goto end; |
| 241 | if (bufsz < start || bufsz - start < len) { |
| 242 | except(jni, "java/lang/IndexOutOfBoundsException", |
| 243 | "bad receive-buffer bounds"); |
| 244 | goto end; |
| 245 | } |
| 246 | |
| 247 | p = (*jni)->GetByteArrayElements(jni, buf, ©p); |
| 248 | if (!p) goto end; |
| 249 | |
| 250 | rc = recv(conn->fd, p + start, len, 0); |
| 251 | if (rc < 0) { |
| 252 | except_errno(jni, "java/io/IOException", errno); |
| 253 | goto end; |
| 254 | } |
| 255 | if (!rc) rc = -1; |
| 256 | |
| 257 | end: |
| 258 | if (p) (*jni)->ReleaseByteArrayElements(jni, buf, p, 0); |
| 259 | if (conn) close_struct(jni, &op); |
| 260 | return (rc); |
| 261 | } |
| 262 | |
| 263 | JNIEXPORT void JNICALL Java_uk_org_distorted_tripe_JNI_close |
| 264 | (JNIEnv *jni, jobject cls, wrapped wconn, jint how) |
| 265 | { |
| 266 | struct conn *conn = 0; |
| 267 | struct open op; |
| 268 | |
| 269 | conn = open_struct(jni, wconn, &conn_type, &op); |
| 270 | if (!conn || conn->fd == -1) goto end; |
| 271 | |
| 272 | how &= CF_CLOSEMASK&~conn->f; |
| 273 | conn->f |= how; |
| 274 | fprintf(stderr, ";; closing %u\n", how); |
| 275 | if ((conn->f&CF_CLOSEMASK) == CF_CLOSEMASK) { |
| 276 | close(conn->fd); |
| 277 | conn->fd = -1; |
| 278 | } else { |
| 279 | if (how&CF_CLOSERD) shutdown(conn->fd, SHUT_RD); |
| 280 | if (how&CF_CLOSEWR) shutdown(conn->fd, SHUT_WR); |
| 281 | } |
| 282 | |
| 283 | end: |
| 284 | if (conn) close_struct(jni, &op); |
| 285 | return; |
| 286 | } |