The Android Open Source Project | f6c3871 | 2009-03-03 19:28:47 -0800 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2006 The Android Open Source Project |
| 3 | * |
| 4 | * JNI helper functions. |
| 5 | */ |
| 6 | #define LOG_TAG "JNIHelp" |
| 7 | #include "JNIHelp.h" |
| 8 | #include "utils/Log.h" |
| 9 | |
| 10 | #include <string.h> |
| 11 | #include <assert.h> |
| 12 | |
| 13 | /* |
| 14 | * Register native JNI-callable methods. |
| 15 | * |
| 16 | * "className" looks like "java/lang/String". |
| 17 | */ |
| 18 | int jniRegisterNativeMethods(JNIEnv* env, const char* className, |
| 19 | const JNINativeMethod* gMethods, int numMethods) |
| 20 | { |
| 21 | jclass clazz; |
| 22 | |
| 23 | LOGV("Registering %s natives\n", className); |
| 24 | clazz = (*env)->FindClass(env, className); |
| 25 | if (clazz == NULL) { |
| 26 | LOGE("Native registration unable to find class '%s'\n", className); |
| 27 | return -1; |
| 28 | } |
| 29 | if ((*env)->RegisterNatives(env, clazz, gMethods, numMethods) < 0) { |
| 30 | LOGE("RegisterNatives failed for '%s'\n", className); |
| 31 | return -1; |
| 32 | } |
| 33 | return 0; |
| 34 | } |
| 35 | |
| 36 | /* |
| 37 | * Throw an exception with the specified class and an optional message. |
| 38 | */ |
| 39 | int jniThrowException(JNIEnv* env, const char* className, const char* msg) |
| 40 | { |
| 41 | jclass exceptionClass; |
| 42 | |
| 43 | exceptionClass = (*env)->FindClass(env, className); |
| 44 | if (exceptionClass == NULL) { |
| 45 | LOGE("Unable to find exception class %s\n", className); |
| 46 | assert(0); /* fatal during dev; should always be fatal? */ |
| 47 | return -1; |
| 48 | } |
| 49 | |
| 50 | if ((*env)->ThrowNew(env, exceptionClass, msg) != JNI_OK) { |
| 51 | LOGE("Failed throwing '%s' '%s'\n", className, msg); |
| 52 | assert(!"failed to throw"); |
| 53 | } |
| 54 | return 0; |
| 55 | } |
| 56 | |
| 57 | /* |
| 58 | * Throw a java.IO.IOException, generating the message from errno. |
| 59 | */ |
| 60 | int jniThrowIOException(JNIEnv* env, int errnum) |
| 61 | { |
| 62 | // note: glibc has a nonstandard |
| 63 | // strerror_r that looks like this: |
| 64 | // char *strerror_r(int errnum, char *buf, size_t n); |
| 65 | |
| 66 | const char* message; |
| 67 | char buffer[80]; |
| 68 | char* ret; |
| 69 | |
| 70 | buffer[0] = 0; |
| 71 | ret = (char*) strerror_r(errnum, buffer, sizeof(buffer)); |
| 72 | |
| 73 | if (((int)ret) == 0) { |
| 74 | //POSIX strerror_r, success |
| 75 | message = buffer; |
| 76 | } else if (((int)ret) == -1) { |
| 77 | //POSIX strerror_r, failure |
| 78 | |
| 79 | snprintf (buffer, sizeof(buffer), "errno %d", errnum); |
| 80 | message = buffer; |
| 81 | } else { |
| 82 | //glibc strerror_r returning a string |
| 83 | message = ret; |
| 84 | } |
| 85 | |
| 86 | return jniThrowException(env, "java/io/IOException", message); |
| 87 | } |
| 88 | |