FFmpeg
ffjni.h
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1 /*
2  * JNI utility functions
3  *
4  * Copyright (c) 2015-2016 Matthieu Bouron <matthieu.bouron stupeflix.com>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #ifndef AVCODEC_FFJNI_H
24 #define AVCODEC_FFJNI_H
25 
26 #include <jni.h>
27 #include <stddef.h>
28 
29 /*
30  * Attach permanently a JNI environment to the current thread and retrieve it.
31  *
32  * If successfully attached, the JNI environment will automatically be detached
33  * at thread destruction.
34  *
35  * @param attached pointer to an integer that will be set to 1 if the
36  * environment has been attached to the current thread or 0 if it is
37  * already attached.
38  * @param log_ctx context used for logging, can be NULL
39  * @return the JNI environment on success, NULL otherwise
40  */
41 JNIEnv *ff_jni_get_env(void *log_ctx);
42 
43 /*
44  * Convert a jstring to its utf characters equivalent.
45  *
46  * @param env JNI environment
47  * @param string Java string to convert
48  * @param log_ctx context used for logging, can be NULL
49  * @return a pointer to an array of unicode characters on success, NULL
50  * otherwise
51  */
52 char *ff_jni_jstring_to_utf_chars(JNIEnv *env, jstring string, void *log_ctx);
53 
54 /*
55  * Convert utf chars to its jstring equivalent.
56  *
57  * @param env JNI environment
58  * @param utf_chars a pointer to an array of unicode characters
59  * @param log_ctx context used for logging, can be NULL
60  * @return a Java string object on success, NULL otherwise
61  */
62 jstring ff_jni_utf_chars_to_jstring(JNIEnv *env, const char *utf_chars, void *log_ctx);
63 
64 /*
65  * Extract the error summary from a jthrowable in the form of "className: errorMessage"
66  *
67  * @param env JNI environment
68  * @param exception exception to get the summary from
69  * @param error address pointing to the error, the value is updated if a
70  * summary can be extracted
71  * @param log_ctx context used for logging, can be NULL
72  * @return 0 on success, < 0 otherwise
73  */
74 int ff_jni_exception_get_summary(JNIEnv *env, jthrowable exception, char **error, void *log_ctx);
75 
76 /*
77  * Check if an exception has occurred,log it using av_log and clear it.
78  *
79  * @param env JNI environment
80  * @param log value used to enable logging if an exception has occurred,
81  * 0 disables logging, != 0 enables logging
82  * @param log_ctx context used for logging, can be NULL
83  */
84 int ff_jni_exception_check(JNIEnv *env, int log, void *log_ctx);
85 
86 /*
87  * Jni field type.
88  */
90 
96 
97 };
98 
99 /*
100  * Jni field describing a class, a field or a method to be retrieved using
101  * the ff_jni_init_jfields method.
102  */
103 struct FFJniField {
104 
105  const char *name;
106  const char *method;
107  const char *signature;
109  size_t offset;
111 
112 };
113 
114 /*
115  * Retrieve class references, field ids and method ids to an arbitrary structure.
116  *
117  * @param env JNI environment
118  * @param jfields a pointer to an arbitrary structure where the different
119  * fields are declared and where the FFJNIField mapping table offsets are
120  * pointing to
121  * @param jfields_mapping null terminated array of FFJNIFields describing
122  * the class/field/method to be retrieved
123  * @param global make the classes references global. It is the caller
124  * responsibility to properly release global references.
125  * @param log_ctx context used for logging, can be NULL
126  * @return 0 on success, < 0 otherwise
127  */
128 int ff_jni_init_jfields(JNIEnv *env, void *jfields, const struct FFJniField *jfields_mapping, int global, void *log_ctx);
129 
130 /*
131  * Delete class references, field ids and method ids of an arbitrary structure.
132  *
133  * @param env JNI environment
134  * @param jfields a pointer to an arbitrary structure where the different
135  * fields are declared and where the FFJNIField mapping table offsets are
136  * pointing to
137  * @param jfields_mapping null terminated array of FFJNIFields describing
138  * the class/field/method to be deleted
139  * @param global threat the classes references as global and delete them
140  * accordingly
141  * @param log_ctx context used for logging, can be NULL
142  * @return 0 on success, < 0 otherwise
143  */
144 int ff_jni_reset_jfields(JNIEnv *env, void *jfields, const struct FFJniField *jfields_mapping, int global, void *log_ctx);
145 
146 #endif /* AVCODEC_FFJNI_H */
error
static void error(const char *err)
Definition: target_bsf_fuzzer.c:31
FFJniField::type
enum FFJniFieldType type
Definition: ffjni.h:108
ff_jni_exception_get_summary
int ff_jni_exception_get_summary(JNIEnv *env, jthrowable exception, char **error, void *log_ctx)
Definition: ffjni.c:143
normalize.log
log
Definition: normalize.py:21
ff_jni_reset_jfields
int ff_jni_reset_jfields(JNIEnv *env, void *jfields, const struct FFJniField *jfields_mapping, int global, void *log_ctx)
Definition: ffjni.c:368
FFJniField::offset
size_t offset
Definition: ffjni.h:109
ff_jni_utf_chars_to_jstring
jstring ff_jni_utf_chars_to_jstring(JNIEnv *env, const char *utf_chars, void *log_ctx)
Definition: ffjni.c:129
FF_JNI_CLASS
@ FF_JNI_CLASS
Definition: ffjni.h:91
FFJniFieldType
FFJniFieldType
Definition: ffjni.h:89
FF_JNI_METHOD
@ FF_JNI_METHOD
Definition: ffjni.h:94
FFJniField
Definition: ffjni.h:103
ff_jni_get_env
JNIEnv * ff_jni_get_env(void *log_ctx)
Definition: ffjni.c:53
ff_jni_jstring_to_utf_chars
char * ff_jni_jstring_to_utf_chars(JNIEnv *env, jstring string, void *log_ctx)
Definition: ffjni.c:99
FF_JNI_FIELD
@ FF_JNI_FIELD
Definition: ffjni.h:92
FF_JNI_STATIC_FIELD
@ FF_JNI_STATIC_FIELD
Definition: ffjni.h:93
ff_jni_init_jfields
int ff_jni_init_jfields(JNIEnv *env, void *jfields, const struct FFJniField *jfields_mapping, int global, void *log_ctx)
Definition: ffjni.c:279
ff_jni_exception_check
int ff_jni_exception_check(JNIEnv *env, int log, void *log_ctx)
Definition: ffjni.c:246
FF_JNI_STATIC_METHOD
@ FF_JNI_STATIC_METHOD
Definition: ffjni.h:95
FFJniField::mandatory
int mandatory
Definition: ffjni.h:110
FFJniField::signature
const char * signature
Definition: ffjni.h:107
jni.h
FFJniField::name
const char * name
Definition: ffjni.h:105
FFJniField::method
const char * method
Definition: ffjni.h:106