cmd/pax/pax-flash.c

/***********************************************************************
*                                                                      *
*               This software is part of the ast package               *
*          Copyright (c) 1987-2011 AT&T Intellectual Property          *
*                      and is licensed under the                       *
*                 Eclipse Public License, Version 1.0                  *
*                    by AT&T Intellectual Property                     *
*                                                                      *
*                A copy of the License is available at                 *
*          http://www.eclipse.org/org/documents/epl-v10.html           *
*         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
*                                                                      *
*              Information and Software Systems Research               *
*                            AT&T Research                             *
*                           Florham Park NJ                            *
*                                                                      *
*                 Glenn Fowler <gsf@research.att.com>                  *
*                                                                      *
***********************************************************************/
#pragma prototyped

/*
 * pax solaris flash format
 */

#include "format.h"

#define FLASH_MAGIC "FlAsH-aRcHiVe-"
#define FLASH_DATA  "section_begin=archive"

static int
flash_getprologue(Pax_t* pax, Format_t* fp, register Archive_t* ap, File_t* f, unsigned char* buf, size_t size)
{
    unsigned char*  s;
    unsigned char*  e;
    unsigned char*  t;
    char*       v;
    int     i;
    off_t       n;
    char        version[16];

    if (size < sizeof(FLASH_MAGIC) - 1 || memcmp(buf, FLASH_MAGIC, sizeof(FLASH_MAGIC) - 1))
        return 0;

    /*
     * get the flash format version
     */

    s = buf + sizeof(FLASH_MAGIC) - 1;
    e = buf + size;
    v = version;
    while (v < &version[sizeof(version) - 1] && s < e && *s != '\n')
        *v++ = *s++;
    *v = 0;

    /*
     * skip over the flash headers to the embedded archive
     */

    s = e;
    for (;;)
    {
        if (s >= e)
        {
            if (!(buf = (unsigned char*)paxget(pax, ap, -PAX_DEFBUFFER * PAX_BLOCK, &n)))
                return -1;
            s = buf;
            e = buf + n;
        }
        if (t = (unsigned char*)memchr(s, '\n', e - s))
        {
            if ((t - s) == (sizeof(FLASH_DATA) - 1) && !memcmp(s, FLASH_DATA, sizeof(FLASH_DATA) - 1))
            {
                if (paxseek(pax, ap, -(e - t - 1), SEEK_CUR, 0) < 0)
                    return -1;
                break;
            }
            if (t < e)
            {
                s = t + 1;
                continue;
            }
        }
        if (paxseek(pax, ap, -(e - s), SEEK_CUR, 0) < 0)
            return -1;
        s = e;
    }
    ap->entry = 0;
    ap->swap = 0;
    ap->swapio = 0;
    ap->volume--;
    i = state.volume[0];
    if (getprologue(ap) <= 0)
    {
        error(2, "%s: %s format embedded archive expected", ap->name, fp->name);
        return -1;
    }
    state.volume[0] = i;
    ap->package = strdup(sfprints("%s %s", fp->name, version));
    return 1;
}

Format_t    pax_flash_format =
{
    "flash",
    0,
    "Solaris flash package encapsulated archive",
    0,
    ARCHIVE|IN,
    DEFBUFFER,
    DEFBLOCKS,
    0,
    PAXNEXT(flash),
    0,
    0,
    flash_getprologue,
};

PAXLIB(flash)