doc: wip

docs/book/main.tex

@@ -62,6 +62,8 @@
 
 	\mainmatter
 
+	\chapter{File, file system, and memory size limits}
+
 	\chapter{Magic Numbers}
 
 	\begin{center}
@@ -70,15 +72,32 @@
  			\textbf{Flag} & \textbf{Hexadecimal} & \textbf{ASCII} & \textbf{Data structure}  \\ 
 			\hline
  			STPDFS\_SB\_MAGIC & 0x44505453 & STPD & Superblock \\
+			STDFS\_BLOCK\_SIZE & 512 & &  Block size\\ 
  			\hline
 		\end{tabular}
 	\end{center}
 
 	\chapter{Structures}
 
-	\section{Superblocks}
+	\section{Superblock}
+
+	\subsection{free list}
 
 	\begin{lstlisting}[language=C]
+struct stpdfs_free {
+	uint32_t free[100];
+	uint8_t nfree;
+};
+	\end{lstlisting}
+
+	\subsection{superblock}
+
+	\begin{lstlisting}[language=C]
+
+#define STPDFS_SB_MAGIC 0x44505453
+#define STPDFS_REV      STPDFS_REV_1
+#define STPDFS_REV_1    0x1
+
 struct stpdfs_sb {
 	uint32_t magic;
 	uint32_t isize;
@@ -86,7 +105,7 @@ struct stpdfs_sb {
 	uint32_t free[100];
 	uint8_t nfree;
 	uint8_t revision;
-	uint8_t state;
+	uint16_t state;
 	uint64_t time;
 };
 	\end{lstlisting}
@@ -106,6 +125,46 @@ struct inode {
 	uint64_t modtime;
 };
 	\end{lstlisting}
+	
+	\subsection{flags}
+
+	\begin{center}
+		\begin{tabular}{ |c|c|c|c| } 
+ 			\hline
+	 		\textbf{flags} & \textbf{value} & \textbf{Description}  \\ 
+			\hline
+			STPDFS\_INODE\_ALLOCATED & 1 << 15 & if set inode is allocated \\
+			STPDFS\_INODE\_LARGE\_FILE & 1 << 0 & \\
+			STPDFS\_INODE\_LZP & 1 << 1 & if set data are compressed \\
+			STPDFS\_INODE\_ENC &  1 << 2 & if set data are encrypted \\
+ 		\hline
+		\end{tabular}
+	\end{center}
+
+	\begin{center}
+		\begin{tabular}{ |c|c| }
+			zone 0-6 & direct \\
+			zone 7 & indirect \\
+			zone 8 & double indirect \\
+			zone 9 & triple indirect \\
+		\end{tabular}
+	\end{center}
+
+	\subsection{mode}
+
+	\begin{center}
+		\begin{tabular}{ |c|c|c|c| } 
+ 			\hline
+ 			\textbf{mode} & \textbf{value} & \textbf{Description}  \\ 
+			 STPDFS\_S\_IFSOCK & 0xA000 & \\
+			STPDFS\_S\_IFLNK  & 0xC000 & \\
+			STPDFS\_S\_IFREG & 0x8000 & \\
+			STPDFS\_S\_IFBLK  & 0x6000 & \\
+			STPDFS\_S\_IFDIR &  0x4000 & \\
+ 			\hline
+		\end{tabular}
+	\end{center}
+
 	\appendix
 
 \end{document}

lib/Makefile.am

@@ -1,5 +1,7 @@
 noinst_LIBRARIES = libstpdfs.a
 libstpdfs_a_SOURCES = block.c \
+						inode.c \
+						dir.c
 						superblock.c \
 						compression/lzp.c \
 						crypto/hchacha.c \

lib/crypto/chacha.h

@@ -2,6 +2,7 @@
 # define STPDFS_CRYPTO_CHACHA_H 1
 
 # include <stdint.h>
+# include <stddef.h>
 
 # define CHACHA_CONST1 "expa"
 # define CHACHA_CONST2 "nd 3"

lib/data.c

@@ -0,0 +1,16 @@
+#include "stpdfs.h"
+
+int
+stpdfs_add_data(int fd, struct stpdfs_sb *sb, struct stpdfs_inode *inode, uint8_t *buffer, size_t size)
+{
+	size_t idx;
+	size_t max_zone;
+
+	if (size > STPDFS_BLOCK_SIZE)
+	{
+		for (idx = 0; idx < size / STPDFS_BLOCK_SIZE; idx++)
+		{
+			stpdfs_add_data(fd, sb, inode, buffer, 512 * idx);
+		}
+	}
+}

lib/dir.c

@@ -0,0 +1,63 @@
+#include "stpdfs.h"
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+
+int
+stpdfs_dir_add_entry(int fd, uint8_t inonum, const char *name, uint32_t target)
+{
+	struct stpdfs_inode inode;
+	struct stpdfs_dirent dirent[STPDFS_DIRENT_PER_BLOCK];
+	struct stpdfs_sb sb;
+	size_t max_zone;
+	size_t zone;
+	uint32_t blocknum;
+	
+	stpdfs_read_superblock(fd, &sb);
+	stpdfs_read_inode(fd, inonum, &inode);
+	if (!(inode.mode & STPDFS_S_IFDIR))
+	{
+		return (-1);
+	}
+
+	max_zone = (inode.size + sizeof(struct stpdfs_dirent)) / STPDFS_DIRENT_PER_BLOCK;
+	zone = max_zone;
+
+	if (max_zone > 2113671)
+	{
+
+	}
+	if (max_zone > 16519)
+	{
+
+	}
+	else if (max_zone > 135)
+	{
+
+	}
+	else if (max_zone > 7)
+	{
+	}
+	else
+	{
+		if (inode.zones[max_zone] == 0)
+		{
+			inode.zones[max_zone] = stpdfs_alloc_block(fd, &sb);
+		}
+
+		blocknum = inode.zones[max_zone];
+	}
+
+	stpdfs_read(fd, blocknum, &dirent, sizeof(struct stpdfs_dirent) * STPDFS_DIRENT_PER_BLOCK);
+	dirent[inode.size % STPDFS_DIRENT_PER_BLOCK].inode = target;
+	memcpy(dirent[inode.size % STPDFS_DIRENT_PER_BLOCK].filename, name, STPDFS_NAME_MAX);
+	stpdfs_write(fd, blocknum, &dirent, sizeof(struct stpdfs_dirent) * STPDFS_DIRENT_PER_BLOCK);
+	
+	inode.size += sizeof(struct stpdfs_dirent);
+
+	stpdfs_write_inode(fd, inonum, &inode);
+
+	stpdfs_write(fd, 1, &sb, sizeof(struct stpdfs_sb));
+
+	return (0);
+}

lib/inode.c

@@ -9,14 +9,28 @@ stpdfs_locate_inode(uint32_t inode)
 }
 
 int
-stpdfs_read_inode()
+stpdfs_read_inode(int fd, uint32_t inodenum, struct stpdfs_inode *ino)
 {
+	struct stpdfs_inode inodes[STPDFS_INODES_PER_BLOCK];
+
+	stpdfs_read(fd, 2 + inodenum / STPDFS_INODES_PER_BLOCK, (uint8_t *)&inodes, sizeof(struct stpdfs_inode) * STPDFS_INODES_PER_BLOCK);
+
+	memcpy(ino, &inodes[inodenum % STPDFS_INODES_PER_BLOCK], sizeof(struct stpdfs_inode));
+	
 	return (0);
 }
 
 int
-stpdfs_write_inode()
+stpdfs_write_inode(int fd, uint32_t inodenum, const struct stpdfs_inode *inode)
 {
+	struct stpdfs_inode inodes[STPDFS_INODES_PER_BLOCK];
+
+	stpdfs_read(fd, 2 + inodenum / STPDFS_INODES_PER_BLOCK, (uint8_t *)&inodes, sizeof(struct stpdfs_inode) * STPDFS_INODES_PER_BLOCK);
+
+	memcpy(&inodes[inodenum % STPDFS_INODES_PER_BLOCK], inode, sizeof(struct stpdfs_inode));
+
+	stpdfs_write(fd, 2 + inodenum / STPDFS_INODES_PER_BLOCK, (uint8_t *)&inodes, sizeof(struct stpdfs_inode) * STPDFS_INODES_PER_BLOCK);
+	
 	return (0);
 }
 

lib/stpdfs.h

@@ -16,6 +16,7 @@
 # define STPDFS_NAME_MAX 28
 
 # define STPDFS_INODES_PER_BLOCK (STPDFS_BLOCK_SIZE / (sizeof(struct stpdfs_inode)))
+# define STPDFS_DIRENT_PER_BLOCK (STPDFS_BLOCK_SIZE / (sizeof(struct stpdfs_dirent)))
 
 # define STPDFS_ROOT_INO 1
 
@@ -96,5 +97,7 @@ int stpdfs_read_superblock(int fd, struct stpdfs_sb *sb);
 
 /* inode.c */
 uint32_t stpdfd_alloc_inode(int fd, struct stpdfs_sb *sb);
+int stpdfs_read_inode(int fd, uint32_t inodenum, struct stpdfs_inode *ino);
+int stpdfs_write_inode(int fd, uint32_t inodenum, const struct stpdfs_inode *inode);
 
 #endif /* !STPDFS_H */