Mercurial > sos > sos
changeset 74:36e6fc4a0487
Added the ability to create a new file
The function makeFile will create a file with a given name
TODO: redo the testing program (actually, I will probably do this after adding
append)
| author | Jonathan Pevarnek <pevarnj@gmail.com> |
|---|---|
| date | Tue, 26 Apr 2011 22:38:45 -0400 |
| parents | 4c47b80ad9ac |
| children | c10465be6160 |
| files | .hgignore Makefile include/error.h include/fs.h src/fs.c |
| diffstat | 5 files changed, 40 insertions(+), 2 deletions(-) [+] |
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--- a/.hgignore Tue Apr 26 21:32:20 2011 -0400 +++ b/.hgignore Tue Apr 26 22:38:45 2011 -0400 @@ -8,3 +8,5 @@ ^loader\.bin$ ^cscope\.out$ \.swp$ + +^changes
--- a/Makefile Tue Apr 26 21:32:20 2011 -0400 +++ b/Makefile Tue Apr 26 22:38:45 2011 -0400 @@ -95,10 +95,11 @@ src/dynamic.o: include/std.h include/die.h include/operations.h src/dynamic.o: include/stack.h -src/fs.o: include/fs.h include/std.h include/die.h +src/fs.o: include/fs.h include/std.h include/die.h include/error.h +src/fs.o: include/tod.h src/operations.o: include/operations.h include/std.h include/die.h src/operations.o: include/stack.h include/math.h src/sarpn.o: include/std.h include/die.h include/operations.h include/stack.h src/stack.o: include/stack.h include/std.h include/die.h src/std.o: include/std.h include/die.h -src/testFS.o: include/std.h include/die.h include/fs.h +src/testFS.o: include/std.h include/die.h include/fs.h include/error.h
--- a/include/error.h Tue Apr 26 21:32:20 2011 -0400 +++ b/include/error.h Tue Apr 26 22:38:45 2011 -0400 @@ -27,6 +27,7 @@ #define SIZETOOLARGE 7 //the user requested a size that is too large to be set for a file #define NOTINCACHE 8 #define DISKFULL 9 //every block on the disk is currently set to be in use +#define EXISTS 10 //the user tried to create a file that already exists //Codes: Time of date #define UPTIME 1 //the actual time of date was not set in the system
--- a/include/fs.h Tue Apr 26 21:32:20 2011 -0400 +++ b/include/fs.h Tue Apr 26 22:38:45 2011 -0400 @@ -53,6 +53,7 @@ ErrCode init_fs(u32 devnum, u64 __memsize); ErrCode getFInfo(u32 n, void* de); ErrCode lookupFile(char *fname, u32 *fid); +ErrCode makeFile(char *fname, u32 *fid); ErrCode getFileSize(u32 fid, u32 *size); ErrCode getFileData(u32 fid, void *ptr); ErrCode setFileData(u32 fid, const void *ptr, size_t size);
--- a/src/fs.c Tue Apr 26 21:32:20 2011 -0400 +++ b/src/fs.c Tue Apr 26 22:38:45 2011 -0400 @@ -75,6 +75,39 @@ return mkError(MODFS, NOTFILE, ERROR); } +//makes an empty file with name fname, sets fid to the fid for the new file +//If the file already exists, an error is returned but fid will be set to the +//fid of that file +ErrCode makeFile(char *fname, u32 *fid) +{ + ErrCode err; + if(lookupFile(fname, fid) != mkError(MODFS, NOTFILE, ERROR)) + return mkError(MODFS, EXISTS, ERROR); //the file should not exist + if(isError(err = nextFreeBlock(0, fid))) return err; + + Inode nin; + nin.size = 0; + nin.nblocks = 0; + if(isError(err = setTod(&nin))) return err; + nin.ctime = nin.mtime; + nin._pad0 = nin._pad1 = nin._pad2 = 0; //I am not sure if this is needed... + if(isError(err = writeFSBlock(*fid, &nin))) return err; + + //the block is now on the disk, time to add it to the root inode + Inode *root = readFSBlock(rootLoc); + if(isError(err = setFileSize(rootLoc, root->size + sizeof(Direntry)))) return err; + root = readFSBlock(rootLoc); //just in case the cache get messed up + u32 fileno = root->size/sizeof(Direntry) - 1; + u32 blkno = root->blocks[fileno/DEPBLK]; //block where direntry is + Direntry *dp = readFSBlock(blkno); + if(!dp) return ERR_FSBLKREADFAIL; + dp += fileno%DEPBLK; //dp is set to the current de + dp->inode = *fid; //set the file location + memcpy(dp->fname, fname, FNAMELEN); //set the file name + if(isError(err = sync(blkno))) return err; //update the block + return 0; +} + //PRECON: fid is a valid file id //This sets *size equal to the size of the file ErrCode getFileSize(u32 fid, u32 *size)