1 /* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef ANDROID_PRINTER_H 18 #define ANDROID_PRINTER_H 19 20 #include <android/log.h> 21 22 namespace android { 23 24 // Interface for printing to an arbitrary data stream 25 class Printer { 26 public: 27 // Print a new line specified by 'string'. \n is appended automatically. 28 // -- Assumes that the string has no new line in it. 29 virtual void printLine(const char* string = "") = 0; 30 31 // Print a new line specified by the format string. \n is appended automatically. 32 // -- Assumes that the resulting string has no new line in it. 33 virtual void printFormatLine(const char* format, ...) __attribute__((format (printf, 2, 3))); 34 35 protected: 36 Printer(); 37 virtual ~Printer(); 38 }; // class Printer 39 40 // Print to logcat 41 class LogPrinter : public Printer { 42 public: 43 // Create a printer using the specified logcat and log priority 44 // - Unless ignoreBlankLines is false, print blank lines to logcat 45 // (Note that the default ALOG behavior is to ignore blank lines) 46 LogPrinter(const char* logtag, 47 android_LogPriority priority = ANDROID_LOG_DEBUG, 48 const char* prefix = nullptr, 49 bool ignoreBlankLines = false); 50 51 // Print the specified line to logcat. No \n at the end is necessary. 52 virtual void printLine(const char* string); 53 54 private: 55 void printRaw(const char* string); 56 57 const char* mLogTag; 58 android_LogPriority mPriority; 59 const char* mPrefix; 60 bool mIgnoreBlankLines; 61 }; // class LogPrinter 62 63 // Print to a file descriptor 64 class FdPrinter : public Printer { 65 public: 66 // Create a printer using the specified file descriptor. 67 // - Each line will be prefixed with 'indent' number of blank spaces. 68 // - In addition, each line will be prefixed with the 'prefix' string. 69 FdPrinter(int fd, unsigned int indent = 0, const char* prefix = nullptr); 70 71 // Print the specified line to the file descriptor. \n is appended automatically. 72 virtual void printLine(const char* string); 73 74 private: 75 enum { 76 MAX_FORMAT_STRING = 20, 77 }; 78 79 int mFd; 80 unsigned int mIndent; 81 const char* mPrefix; 82 char mFormatString[MAX_FORMAT_STRING]; 83 }; // class FdPrinter 84 85 class String8; 86 87 // Print to a String8 88 class String8Printer : public Printer { 89 public: 90 // Create a printer using the specified String8 as the target. 91 // - In addition, each line will be prefixed with the 'prefix' string. 92 // - target's memory lifetime must be a superset of this String8Printer. 93 String8Printer(String8* target, const char* prefix = nullptr); 94 95 // Append the specified line to the String8. \n is appended automatically. 96 virtual void printLine(const char* string); 97 98 private: 99 String8* mTarget; 100 const char* mPrefix; 101 }; // class String8Printer 102 103 // Print to an existing Printer by adding a prefix to each line 104 class PrefixPrinter : public Printer { 105 public: 106 // Create a printer using the specified printer as the target. 107 PrefixPrinter(Printer& printer, const char* prefix); 108 109 // Print the line (prefixed with prefix) using the printer. 110 virtual void printLine(const char* string); 111 112 private: 113 Printer& mPrinter; 114 const char* mPrefix; 115 }; 116 117 } // namespace android 118 119 #endif // ANDROID_PRINTER_H 120