Android MediaScanner.cpp Source Code parsing

1. Introduction

Implementing recursive scanning of folders
Libmedia–libmedia.so
Frameworks\av\media\libmedia\mediascanner.cpp

2. Scanning of files

The processdirectory is called by JNI, and then the recursive scan of the folder is implemented by Doprocessdirectory and Doprocessdirectoryentry.

2.1 Doprocessdirectory

Cycle through all items in the folder

Mediascanresult Mediascanner::d oprocessdirectory (Char*path,intPathremaining, Mediascannerclient &client,BOOLNoMedia) {Char* Filespot = path + strlen (path);structdirent* entry; .....//Treat All files as Non-media in directories that contain a ". Nomedia" File.....//skip. nomedia filedir*dir= Opendir (path); Mediascanresult result = MEDIA_SCAN_RESULT_OK; while(Entry = Readdir (dir))) {if(Doprocessdirectoryentry (path, pathremaining, client, NoMedia, entry, filespot) = = Media_scan_result_error) {result = Media_scan_result_error; Break; }} closedir (dir);returnResult;}

2.2 Doprocessdirectoryentry

determines whether the item is a file, a folder, or an item that needs to be skipped.
If folder
Doprocessdirectory
else if file
Calling Java layer Scanfile via JNI
else if Skip
Skip this file or folder

Mediascanresult Mediascanner::d oprocessdirectoryentry (Char*path,intPathremaining, Mediascannerclient &client,BOOLNoMedia,structdirent* entry,Char* Filespot) {structStat statbuf;Const Char* Name = entry->d_name; ........int type= entry->d_type;if(type= = Dt_unknown) {if(Stat (path, &statbuf) = =0) {if(S_isreg (Statbuf.st_mode)) {//Documents                type= Dt_reg; }Else if(S_isdir (Statbuf.st_mode)) {//Folder                type= Dt_dir; }        }    }if(type= = Dt_dir) {BOOLChildnomedia = NoMedia;//Set NoMedia flag on directories with a name the starts with '. '        //For example, the MAC. Trashes "Directory        if(name[0] =='. ') Childnomedia =true;// Report of the directory to the client        if(Stat (path, &statbuf) = =0{status_t status = Client.scanfile (path, Statbuf.st_mtime,0,true /*isdirectory*/, Childnomedia);if(status) {returnMedia_scan_result_error; }        }//And now process its contentsstrcat (Filespot,"/"); Mediascanresult result = doprocessdirectory (path, Pathremaining-namelength-1, client, Childnomedia);if(Result = = Media_scan_result_error) {returnMedia_scan_result_error; }    }Else if(type= = Dt_reg) {stat (path, &statbuf); status_t status = Client.scanfile (path, Statbuf.st_mtime, Statbuf.st_size,false /*isdirectory*/, NoMedia);if(status) {returnMedia_scan_result_error; }    }returnMEDIA_SCAN_RESULT_OK;}

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Android MediaScanner.cpp Source Code parsing