osc2021/include/cpio.h at 9f21d9147fa65da23a11d538d4cc4f2e1b42f411 · GrassLab/osc2021 · GitHub

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/*
 * Code modified from SEL4PROJ@github (https://github.com/SEL4PROJ/libcpio)
 */

/*
 * Parse cpio archive files in "New ASCII Format"
 *
 * Freebsd’s man page (https://www.freebsd.org/cgi/man.cgi?query=cpio&sektion=5)
 * has a detailed definition of how New ASCII Format Cpio Archive is structured.
 */

#ifndef _LIB_CPIO_H_
#define _LIB_CPIO_H_

#include "base.h"

/* Magic identifiers for the "cpio" file format. */
#define CPIO_HEADER_MAGIC "070701"
#define CPIO_FOOTER_MAGIC "TRAILER!!!"
#define CPIO_ALIGNMENT 4

#define INITRAMFS_ADDR (void *)0x8000000 + VA_START

#ifndef NULL
#define NULL ((void *)0)
#endif

/* CPIO "New ASCII Format" header structure */
struct cpio_header {
    char c_magic[6];      /* Magic header '070701'. */
    char c_ino[8];        /* "i-node" number. */
    char c_mode[8];       /* The mode specifies	both the regular permissions and the file type. */
    char c_uid[8];        /* User ID. */
    char c_gid[8];        /* Group ID. */
    char c_nlink[8];      /* Number of hard links. */
    char c_mtime[8];      /* Modification time. */
    char c_filesize[8];   /* File size. */
    char c_devmajor[8];   /* Major dev number. */
    char c_devminor[8];   /* Minor dev number. */
    char c_rdevmajor[8];
    char c_rdevminor[8];
    char c_namesize[8];   /* Length of filename in bytes. */
    char c_check[8];      /* Checksum. */
};

/**
 *
 * Return value define for cpio_parse_header()
 *
 */
 // TODO:
 // Embed this object to cpio_parse_header function
// enum cpio_parse_header_result
// {
//     notValid = -1,
//     OK = 0,
//     EOF = 1
// };

/**
 * Stores information about the underlying implementation.
 */
struct cpio_info {
    /// The number of files in the CPIO archive
    unsigned int file_count;
    /// The maximum size of a file name
    unsigned int max_path_sz;
};

/**
 * Parse the header of the given CPIO entry.
 * Return -1 if the header is not valid, 1 if it is EOF.
 *
 * @param[in] archive     The location of the CPIO archive
 * @param[out] filename   ###The name of the file in question.
 * @param[out] filesize  ###The filesize of the file in question.
 * @param[out] data       ###The data of the file in question.
 * @param[out] next       ####The next file in question.
 */
int cpio_parse_header(struct cpio_header *archive,
        const char **filename, unsigned long *_filesize, void **data,
        struct cpio_header **next);

/**
 * Retrieve file information from a provided file name
 * @param[in] archive  The location of the CPIO archive
 * @param[in] name     The name of the file in question.
 * @param[out] size    The retrieved size of the file in question
 * @return             The location of the file in memory; NULL if the file
 *                     does not exist.
 */
void *cpio_get_file(void *archive, const char *name, unsigned long *size);

/**
 * Writes the list of file names contained within a CPIO archive into
 * a provided buffer
 * @param[in] archive  The location of the CPIO archive
 * @param[in] buf      A memory location to store the CPIO file list to
 * @param[in] buf_len  The length of the provided buf
 */
void cpio_ls(void *archive);

void *cpio_move_file(void *archive, const char *name, unsigned long move_addr);
#endif /* _LIB_CPIO_H_ */