1 /* system/core/include/logwrap/logwrap.h 2 * 3 * Copyright 2013, The Android Open Source Project 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 #ifndef __LIBS_LOGWRAP_H 19 #define __LIBS_LOGWRAP_H 20 21 #include <stdbool.h> 22 #include <stdint.h> 23 24 __BEGIN_DECLS 25 26 /* 27 * Run a command while logging its stdout and stderr 28 * 29 * WARNING: while this function is running it will clear all SIGCHLD handlers 30 * if you rely on SIGCHLD in the caller there is a chance zombies will be 31 * created if you're not calling waitpid after calling this. This function will 32 * log a warning when it clears SIGCHLD for processes other than the child it 33 * created. 34 * 35 * Arguments: 36 * argc: the number of elements in argv 37 * argv: an array of strings containing the command to be executed and its 38 * arguments as separate strings. argv does not need to be 39 * NULL-terminated 40 * status: the equivalent child status as populated by wait(status). This 41 * value is only valid when logwrap successfully completes. If NULL 42 * the return value of the child will be the function's return value. 43 * ignore_int_quit: set to true if you want to completely ignore SIGINT and 44 * SIGQUIT while logwrap is running. This may force the end-user to 45 * send a signal twice to signal the caller (once for the child, and 46 * once for the caller) 47 * log_target: Specify where to log the output of the child, either LOG_NONE, 48 * LOG_ALOG (for the Android system log), LOG_KLOG (for the kernel 49 * log), or LOG_FILE (and you need to specify a pathname in the 50 * file_path argument, otherwise pass NULL). These are bit fields, 51 * and can be OR'ed together to log to multiple places. 52 * abbreviated: If true, capture up to the first 100 lines and last 4K of 53 * output from the child. The abbreviated output is not dumped to 54 * the specified log until the child has exited. 55 * file_path: if log_target has the LOG_FILE bit set, then this parameter 56 * must be set to the pathname of the file to log to. 57 * opts: set to non-NULL if you want to use one or more of the 58 * FORK_EXECVP_OPTION_* features. 59 * opts_len: the length of the opts array. When opts is NULL, pass 0. 60 * 61 * Return value: 62 * 0 when logwrap successfully run the child process and captured its status 63 * -1 when an internal error occurred 64 * -ECHILD if status is NULL and the child didn't exit properly 65 * the return value of the child if it exited properly and status is NULL 66 * 67 */ 68 69 /* Values for the log_target parameter android_fork_execvp_ext() */ 70 #define LOG_NONE 0 71 #define LOG_ALOG 1 72 #define LOG_KLOG 2 73 #define LOG_FILE 4 74 75 /* Write data to child's stdin. */ 76 #define FORK_EXECVP_OPTION_INPUT 0 77 /* Capture data from child's stdout and stderr. */ 78 #define FORK_EXECVP_OPTION_CAPTURE_OUTPUT 1 79 80 struct AndroidForkExecvpOption { 81 int opt_type; 82 union { 83 struct { 84 const uint8_t* input; 85 size_t input_len; 86 } opt_input; 87 struct { 88 void (*on_output)(const uint8_t* /*output*/, 89 size_t /*output_len*/, 90 void* /* user_pointer */); 91 void* user_pointer; 92 } opt_capture_output; 93 }; 94 }; 95 96 int android_fork_execvp_ext(int argc, char* argv[], int *status, bool ignore_int_quit, 97 int log_target, bool abbreviated, char *file_path, 98 const struct AndroidForkExecvpOption* opts, size_t opts_len); 99 100 /* Similar to above, except abbreviated logging is not available, and if logwrap 101 * is true, logging is to the Android system log, and if false, there is no 102 * logging. 103 */ 104 static inline int android_fork_execvp(int argc, char* argv[], int *status, 105 bool ignore_int_quit, bool logwrap) 106 { 107 return android_fork_execvp_ext(argc, argv, status, ignore_int_quit, 108 (logwrap ? LOG_ALOG : LOG_NONE), false, NULL, 109 NULL, 0); 110 } 111 112 __END_DECLS 113 114 #endif /* __LIBS_LOGWRAP_H */ 115