| 1 | // |
| 2 | // Copyright 2011 The Android Open Source Project |
| 3 | // |
| 4 | // Defines an abstraction for opening a directory on the filesystem and |
| 5 | // iterating through it. |
| 6 | |
| 7 | #ifndef DIRECTORYWALKER_H |
| 8 | #define DIRECTORYWALKER_H |
| 9 | |
| 10 | #include <dirent.h> |
| 11 | #include <sys/types.h> |
| 12 | #include <sys/param.h> |
| 13 | #include <sys/stat.h> |
| 14 | #include <unistd.h> |
| 15 | #include <utils/String8.h> |
| 16 | |
| 17 | #include <stdio.h> |
| 18 | |
| 19 | using namespace android; |
| 20 | |
| 21 | // Directory Walker |
| 22 | // This is an abstraction for walking through a directory and getting files |
| 23 | // and descriptions. |
| 24 | |
| 25 | class DirectoryWalker { |
| 26 | public: |
| 27 | virtual ~DirectoryWalker() {}; |
| 28 | virtual bool openDir(String8 path) = 0; |
| 29 | virtual bool openDir(const char* path) = 0; |
| 30 | // Advance to next directory entry |
| 31 | virtual struct dirent* nextEntry() = 0; |
| 32 | // Get the stats for the current entry |
| 33 | virtual struct stat* entryStats() = 0; |
| 34 | // Clean Up |
| 35 | virtual void closeDir() = 0; |
| 36 | // This class is able to replicate itself on the heap |
| 37 | virtual DirectoryWalker* clone() = 0; |
| 38 | |
| 39 | // DATA MEMBERS |
| 40 | // Current directory entry |
| 41 | struct dirent mEntry; |
| 42 | // Stats for that directory entry |
| 43 | struct stat mStats; |
| 44 | // Base path |
| 45 | String8 mBasePath; |
| 46 | }; |
| 47 | |
| 48 | // System Directory Walker |
| 49 | // This is an implementation of the above abstraction that calls |
| 50 | // real system calls and is fully functional. |
| 51 | // functions are inlined since they're very short and simple |
| 52 | |
| 53 | class SystemDirectoryWalker : public DirectoryWalker { |
| 54 | |
| 55 | // Default constructor, copy constructor, and destructor are fine |
| 56 | public: |
| 57 | virtual bool openDir(String8 path) { |
| 58 | mBasePath = path; |
| 59 | dir = NULL; |
| 60 | dir = opendir(mBasePath.string() ); |
| 61 | |
| 62 | if (dir == NULL) |
| 63 | return false; |
| 64 | |
| 65 | return true; |
| 66 | }; |
| 67 | virtual bool openDir(const char* path) { |
| 68 | String8 p(path); |
| 69 | openDir(p); |
| 70 | return true; |
| 71 | }; |
| 72 | // Advance to next directory entry |
| 73 | virtual struct dirent* nextEntry() { |
| 74 | struct dirent* entryPtr = readdir(dir); |
| 75 | if (entryPtr == NULL) |
| 76 | return NULL; |
| 77 | |
| 78 | mEntry = *entryPtr; |
| 79 | // Get stats |
| 80 | String8 fullPath = mBasePath.appendPathCopy(mEntry.d_name); |
| 81 | stat(fullPath.string(),&mStats); |
| 82 | return &mEntry; |
| 83 | }; |
| 84 | // Get the stats for the current entry |
| 85 | virtual struct stat* entryStats() { |
| 86 | return &mStats; |
| 87 | }; |
| 88 | virtual void closeDir() { |
| 89 | closedir(dir); |
| 90 | }; |
| 91 | virtual DirectoryWalker* clone() { |
| 92 | return new SystemDirectoryWalker(*this); |
| 93 | }; |
| 94 | private: |
| 95 | DIR* dir; |
| 96 | }; |
| 97 | |
| 98 | #endif // DIRECTORYWALKER_H |