On 09/27/16 17:07, Carsey, Jaben wrote: > Apparently all the good threads happen at night for me...
The blessings of a distributed team! ;) > Kesheva, > > There are a few functions in the ShellLib that call into the UEFI Shell > binary to help you. Some of these are duplicates of what others suggested, > but I figured I would elaborate. I appreciate that, thanks! Cheers, Laszlo > ShellOpenFileMetaArg - open a file or group of files. can handle something > like "open *.txt" > ShellOpenFileByName - open a single file. > > These functions in turn call into functions in the ShellProtocol that the > UEFI Shell produces during the time it is running. > > ShellOpenFileMetaArg calls into gEfiShellProtocol->OpenFileList > ShellOpenFileByName calls into gEfiShellProtocol->OpenFileByName > > There is some examples of use of these functions in the files for the > commands "Touch" and "Type" and these are located in: > ShellPkg\Library\UefiShellLevel3CommandsLib > > > -Jaben > >> -----Original Message----- >> From: edk2-devel [mailto:[email protected]] On Behalf Of >> GN Keshava >> Sent: Tuesday, September 27, 2016 4:52 AM >> To: Laszlo Ersek <[email protected]> >> Cc: [email protected] <[email protected]> >> Subject: Re: [edk2] How to open a file by it's full path in UEFI >> >> Thank you Laszlo. >> >> I'll check it out. :) >> >> Thanks again. >> Regards, >> Keshava >> >> On Tue, 27 Sep 2016 at 16:47 Laszlo Ersek <[email protected]> wrote: >> >>> On 09/27/16 12:46, GN Keshava wrote: >>>> Hi Laszlo, >>>> >>>> Thank you for the answer. It was helpful. >>>> >>>> Considering option #1, can you give some more details (a small example >>>> or any reference link would be helpful), how I can use Shell APIs in my >>>> C file (which will compile to my .efi app)? >>> >>> Hmmm, I don't have hands-on experience with this, but you might want to >>> try the ShellOpenFileByName() function, from >>> "ShellPkg/Include/Library/ShellLib.h". >>> >>> You can find examples for UEFI applications that use the Shell library >>> with: >>> >>> git grep -w ShellLib -- '*inf' >>> >>> or just grep the tree for ShellOpenFileByName(). >>> >>> See also "AppPkg/ReadMe.txt". >>> >>>> Considering option #2, How I can find device path programatically from >>>> my C file? >>> >>> The EFI_SHELL_PROTOCOL.GetDevicePathFromMap() member function >> seems >>> relevant -- it is specified in the UEFI Shell spec --, but I would >>> definitely try ShellOpenFileByName() first. >>> >>> Thanks >>> Laszlo >>> >>>> Thanks again for the help. :) >>>> With regards, >>>> Keshava >>>> >>>> On Tue, 27 Sep 2016 at 15:19 Laszlo Ersek <[email protected] >>>> <mailto:[email protected]>> wrote: >>>> >>>> On 09/27/16 11:25, GN Keshava wrote: >>>> > Hi Laszlo, >>>> > >>>> > Thanks for the reply. I meant I have complete file path. I believe >>> the >>>> > "device path" is different. Is it possible to obtain DevicePath >>>> using my >>>> > full file path? >>>> >>>> The pathname you seem to have (as "complete") is specific to a given >>>> simple FS, so system-wide it cannot be considered complete (there >>> can be >>>> multiple filesystems). >>>> >>>> In your original email I missed that you started with "FS1:". >>> Andrew's >>>> answer covers that case. >>>> >>>> In summary, you can do three things: >>>> - have a pathname that starts with FSx: (which is a shell-specific >>>> mapping), and use Andrew's recommendation, >>>> - have a complete UEFI device path, and then use what I >> recommended, >>>> - have no information for selecting the filesystem (from the many >>>> possible), and use your current iteration. >>>> >>>> Options #1 and #2 actually correspond to each other, considering >>>> "expressive power" / information content (as long as you are in the >>>> shell); please see the MAP shell command. >>>> >>>> Thanks >>>> Laszlo >>>> >>>> > On Tue, 27 Sep 2016 at 14:46 Laszlo Ersek <[email protected] >>>> <mailto:[email protected]> >>>> > <mailto:[email protected] <mailto:[email protected]>>> wrote: >>>> > >>>> > On 09/27/16 11:03, GN Keshava wrote: >>>> > > Hi all, >>>> > > >>>> > > >>>> > > I'm trying to open a file from my UEFI application. The path >>> of >>>> > file is >>>> > > >>>> > > fs1:/myfolder/myfile.txt >>>> > > >>>> > > The code : >>>> > > >>>> > > efiStatus = bs->LocateHandleBuffer(ByProtocol, >>>> > > &sfspGuid, >>>> > > NULL, >>>> > > &handleCount, >>>> > > &handles); >>>> > > >>>> > > for (index = 0; index < (int)handleCount; ++ index) >>>> > > { >>>> > > EFI_SIMPLE_FILE_SYSTEM_PROTOCOL* fs = NULL; >>>> > > >>>> > > efiStatus = bs->HandleProtocol( >>>> > > handles[index], >>>> > > &sfspGuid, >>>> > > (void**)&fs); >>>> > > >>>> > > EFI_FILE_PROTOCOL* root = NULL; >>>> > > ... >>>> > > efiStatus = fs->OpenVolume(fs, &root); >>>> > > >>>> > > EFI_FILE_PROTOCOL* token = NULL; >>>> > > >>>> > > efiStatus = root->Open( >>>> > > root, >>>> > > &token, >>>> > > L"myfolder\\myfile.txt", >>>> > > EFI_FILE_MODE_READ, >>>> > > EFI_FILE_READ_ONLY | EFI_FILE_HIDDEN | >>> EFI_FILE_SYSTEM); >>>> > > } >>>> > > >>>> > > But using this method, I can only go through all the file >>> system >>>> > handles >>>> > > and open each volume and try opening my file. >>>> > > >>>> > > But I want to give full path to my file and open it in it's >>>> volume. >>>> > > >>>> > > How can I acheive this? >>>> > > Thanks. >>>> > >>>> > If you have a complete device path, you can use >>>> gBS->LocateDevicePath() >>>> > with gEfiSimpleFileSystemProtocolGuid, to locate the handle >>>> with the >>>> > most specific device path (--> the longest device path prefix) >>>> with the >>>> > simple FS protocol installed on it. Then you can check if the >>>> remaining >>>> > device path (returned by the service) consist of nothing but >>>> one File >>>> > Path Media Device Path node. If so, you can open the simple FS >>>> protocol >>>> > on the handle found, then use that to open the file by >>> pathname. >>>> > >>>> > Laszlo >>>> > >>>> >>> >>> >> _______________________________________________ >> edk2-devel mailing list >> [email protected] >> https://lists.01.org/mailman/listinfo/edk2-devel _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
