cdinstall.c

linux 安装程序

/*
 * cdinstall.c - code to set up cdrom installs
 *
 * Erik Troan <[e-mail]>
 * Matt Wilson <[e-mail]>
 * Michael Fulbright <[e-mail]>
 * Jeremy Katz <[e-mail]>
 *
 * Copyright 1997 - 2003 Red Hat, Inc.
 *
 * This software may be freely redistributed under the terms of the GNU
 * General Public License.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <newt.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mount.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <asm/types.h>
#include <linux/cdrom.h>

#include "kickstart.h"
#include "loader.h"
#include "loadermisc.h"
#include "log.h"
#include "lang.h"
#include "modules.h"
#include "method.h"
#include "cdinstall.h"
#include "mediacheck.h"

#include "../isys/imount.h"
#include "../isys/isys.h"

/* boot flags */
extern int flags;

static int getISOStatusFromFD(int isofd, char *mediasum);

/* ejects the CD device the device node /tmp/cdrom points at */
void ejectCdrom(void) {
    int ejectfd;

    logMessage(INFO, "ejecting /tmp/cdrom...");
    if ((ejectfd = open("/tmp/cdrom", O_RDONLY | O_NONBLOCK, 0)) >= 0) {
        if (ioctl(ejectfd, CDROMEJECT, 0))
            logMessage(ERROR, "eject failed %d ", errno);
        close(ejectfd);
    } else {
        logMessage(ERROR, "eject failed %d ", errno);
    }
}

/*
 * Given cd device cddriver, this function will attempt to check its internal
 * checksum.
 *
 * JKFIXME: this ignores "location", which should be fixed */
static char * mediaCheckCdrom(char *cddriver) {
    int rc;
    int first;

    devMakeInode(cddriver, "/tmp/cdrom");

    first = 1;
    do {
        char *descr;
        char *tstamp;
        int ejectcd;

        /* init every pass */
        ejectcd = 0;
        descr = NULL;

        /* if first time through, see if they want to eject the CD      */
        /* currently in the drive (most likely the CD they booted from) */
        /* and test a different disk.  Otherwise just test the disk in  */
        /* the drive since it was inserted in the previous pass through */
        /* this loop, so they want it tested.                           */
        if (first) {
            first = 0;
            rc = newtWinChoice(_("Media Check"), _("Test"), _("Eject CD"),
                               _("Choose \"%s\" to test the CD currently in "
                                 "the drive, or \"%s\" to eject the CD and "
                                 "insert another for testing."), _("Test"),
                               _("Eject CD"));

            if (rc == 2)
                ejectcd = 1;
        }

        if (!ejectcd) {
            /* XXX MSFFIXME: should check return code for error */
            readStampFileFromIso("/tmp/cdrom", &tstamp, &descr);
            mediaCheckFile("/tmp/cdrom", descr);

            if (descr)
                free(descr);
        }

        ejectCdrom();
	
        rc = newtWinChoice(_("Media Check"), _("Test"), _("Continue"),
                       _("If you would like to test additional media, "
                       "insert the next CD and press \"%s\". "
                       "Testing each CD is not strictly required, however "
                       "it is highly recommended.  Minimally, the CDs should "
                       "be tested prior to using them for the first time. "
                       "After they have been successfully tested, it is not "
                       "required to retest each CD prior to using it again."),
                       _("Test"), _("Continue"));

        if (rc == 2) {
            unlink("/tmp/cdrom");
            return NULL;
        } else {
            continue;
        }
    } while (1);
    
    return NULL;
}

/* output an error message when CD in drive is not the correct one */
/* Used by mountCdromStage2()                                      */
static void wrongCDMessage(void) {
    char *buf = sdupprintf(_("The %s CD was not found "
                             "in any of your CDROM drives. Please insert "
                             "the %s CD and press %s to retry."),
                           getProductName(), getProductName(), _("OK"));
    newtWinMessage(_("Error"), _("OK"), buf, _("OK"));
    free(buf);
}

/* Attempts to get a proper CD #1 in the drive */
/* Is called after mediacheck is done so that we can proceed with the install */
/* During mediacheck we have to have CD umount'd so it can be ejected */
/*                                                                    */
/* JKFIXME: Assumes CD is mounted as /mnt/source                      */
static void mountCdromStage2(char *cddev) {
    int gotcd1=0;
    int rc;

    devMakeInode(cddev, "/tmp/cdrom");
    do {
        do {
            if (doPwMount("/tmp/cdrom", "/mnt/source", 
                          "iso9660", IMOUNT_RDONLY, NULL)) {
                ejectCdrom();
                wrongCDMessage();
            } else {
                break;
            }
        } while (1);

        rc = mountStage2("/mnt/source/images/stage2.img");

        /* if we failed, umount /mnt/source and keep going */
        if (rc) {
            umount("/mnt/source");
            ejectCdrom();
            wrongCDMessage();
        } else {
            gotcd1 = 1;
        }
    } while (!gotcd1);
}

/* reads iso status from device cddriver */
static int getISOStatusFromCDROM(char *cddriver, char *mediasum) {
    int isofd;
    int isostatus;

    devMakeInode(cddriver, "/tmp/cdrom");
    isofd = open("/tmp/cdrom", O_RDONLY);
    if (isofd < 0) {
        logMessage(WARNING, "Could not check iso status: %s", strerror(errno));
        unlink("/tmp/cdrom");
        return 0;
    }

    isostatus = getISOStatusFromFD(isofd, mediasum);

    close(isofd);
    unlink("/tmp/cdrom");

    return isostatus;
}

/* get support status */
/* if returns 1 we found status, and mediasum will be checksum */
static int getISOStatusFromFD(int isofd, char *mediasum) {
    char tmpsum[33];
    char fragmentsums[FRAGMENT_SUM_LENGTH+1];
    int skipsectors, isostatus;
    long long isosize, pvd_offset, fragmentcount = 0;

    if (mediasum)
        mediasum[0] = '\0';

    fragmentsums[0] = '\0';

    pvd_offset = parsepvd(isofd, tmpsum, &skipsectors, &isosize, &isostatus,
                          fragmentsums, &fragmentcount);
    if (pvd_offset < 0) {
        logMessage(ERROR, "Could not parse pvd");
        return 0;
    }

    if (mediasum)
        strcpy(mediasum, tmpsum);

    return isostatus;
}

/* writes iso status info to file '/tmp/isoinfo' for later use */
static void writeISOStatus(int status, char *mediasum) {
    FILE *f;

    if (!(f = fopen("/tmp/isoinfo", "w")))
        return;

    fprintf(f, "ISOSTATUS=%d\n", status);
    fprintf(f, "MEDIASUM=%s\n", mediasum);

    fclose(f);
}

/* ask about doing media check */
/* JKFIXME: Assumes CD is mounted as /mnt/source                      */
static void queryCDMediaCheck(char *dev) {
    int rc;
    char mediasum[33];
    int isostatus;

    /* dont bother to test in automated installs */
    if (FL_KICKSTART(flags) && !FL_MEDIACHECK(flags))
        return;

    /* see what status is */
    isostatus = getISOStatusFromCDROM(dev, mediasum);
    writeISOStatus(isostatus, mediasum);

    /* see if we should check image(s) */
    /* in rescue mode only test if they explicitly asked to */
    if ((!isostatus && !FL_RESCUE(flags)) || FL_MEDIACHECK(flags)) {
        startNewt();
        rc = newtWinChoice(_("CD Found"), _("OK"), _("Skip"), 
             _("To begin testing the CD media before installation press %s.\n\n"
               "Choose %s to skip the media test and start the installation."),
             _("OK"), _("Skip"));

        if (rc != 2) {
            /* unmount CD now we've identified */
            /* a valid disc #1 is present */
            umountStage2();
            umount("/mnt/source");
      
            /* test CD(s) */
            mediaCheckCdrom(dev);
      
            /* remount stage2 from CD #1 and proceed */
            mountCdromStage2(dev);
        }
    }
}

/* set up a cdrom, nominally for installation 
 *
 * location: where to mount the cdrom at JKFIXME: ignored
 * interactive: whether or not to prompt about questions/errors (1 is yes)
 *
 * loaderData is the kickstart info, can be NULL meaning no info
 *
 * requirepkgs=1 means CD should have packages, otherwise we just find stage2
 *
 * side effect: found cdrom is mounted as /mnt/source.  stage2 mounted
 * as /mnt/runtime.
 */
char * setupCdrom(char * location, struct loaderData_s * loaderData,
                  moduleInfoSet modInfo, moduleList modLoaded, 
                  moduleDeps modDeps, int interactive, int requirepkgs) {
    int i, r, rc;
    int foundinvalid = 0;
    int stage2inram = 0;
    char * buf;
    char *stage2img;
    struct device ** devices;

    devices = probeDevices(CLASS_CDROM, BUS_UNSPEC, 0);
    if (!devices) {
        logMessage(ERROR, "got to setupCdrom without a CD device");
        return NULL;
    }

    /* JKFIXME: ASSERT -- we have a cdrom device when we get here */
    do {
        for (i = 0; devices[i]; i++) {
            if (!devices[i]->device)
                continue;

            logMessage(INFO,"trying to mount CD device %s", devices[i]->device);

            if (devMakeInode(devices[i]->device, "/tmp/cdrom") != 0) {
                logMessage(ERROR, "unable to create device node for %s",
                           devices[i]->device);
                continue;
            }

            if (!doPwMount("/tmp/cdrom", "/mnt/source", "iso9660", 
                           IMOUNT_RDONLY, NULL)) {
                if (!access("/mnt/source/images/stage2.img", R_OK) &&
                    (!requirepkgs || !access("/mnt/source/.discinfo", R_OK))) {

                    /* if in rescue mode lets copy stage 2 into RAM so we can */
                    /* free up the CD drive and user can have it avaiable to  */
                    /* aid system recovery.                                   */
                    if (FL_RESCUE(flags) && !FL_TEXT(flags) &&
                        totalMemory() > 128000) {
                        rc = copyFile("/mnt/source/images/stage2.img", 
                                      "/tmp/ramfs/stage2.img");
                        stage2img = "/tmp/ramfs/stage2.img";
                        stage2inram = 1;
                    } else {
                        stage2img = strdup("/mnt/source/images/stage2.img");
                        stage2inram = 0;
                    }
	
                    rc = mountStage2(stage2img);

                    /* if we failed, umount /mnt/source and keep going */
                    if (rc) {
                        logMessage(INFO, "mounting stage2 failed");

                        umount("/mnt/source");
                        if (rc == -1)
                            foundinvalid = 1;
                        continue;
                    }

                    /* do the media check */
                    queryCDMediaCheck(devices[i]->device);

                    /* if in rescue mode and we copied stage2 to RAM */
                    /* we can now unmount the CD                     */
                    if (FL_RESCUE(flags) && stage2inram) {
                        umount("/mnt/source");
                        unlink("/tmp/cdrom");
                    }

                    r = asprintf(&buf, "cdrom://%s:/mnt/source",
                                 devices[i]->device);
                    if (r == -1)
                        return NULL;
                    else
                        return buf;

                }

                /* this wasnt the CD we were looking for, clean up and */
                /* try the next CD drive                               */
                umount("/mnt/source");
            }
        }

        if (interactive) {
            char * buf;
            if (foundinvalid)
                buf = sdupprintf(_("No %s CD was found which matches your "
                                   "boot media.  Please insert the %s CD "
                                   "and press %s to retry."), getProductName(),
                                 getProductName(), _("OK"));
            else
                buf = sdupprintf(_("The %s CD was not found in any of your "
                                   "CDROM drives. Please insert the %s CD "
                                   "and press %s to retry."), getProductName(),
                                 getProductName(), _("OK"));

            ejectCdrom();
            unlink("/tmp/cdrom");
            rc = newtWinChoice(_("CD Not Found"),
                               _("OK"), _("Back"), buf, _("OK"));
            free(buf);
            if (rc == 2)
                return NULL;
        } else {
            /* we can't ask them about it, so just return not found */
            return NULL;
        }
    } while (1);

    return NULL;
}

/* try to find a install CD non-interactively */
char * findAnacondaCD(char * location, 
                    moduleInfoSet modInfo, 
                    moduleList modLoaded, 
                    moduleDeps modDeps, 
                    int requirepkgs) {
    return setupCdrom(location, NULL, modInfo, modLoaded, modDeps, 0, requirepkgs);
}

/* look for a CD and mount it.  if we have problems, ask */
char * mountCdromImage(struct installMethod * method,
                       char * location, struct loaderData_s * loaderData,
                       moduleInfoSet modInfo, moduleList modLoaded,
                       moduleDeps * modDepsPtr) {

    return setupCdrom(location, loaderData, modInfo, modLoaded, *modDepsPtr, 1, 1);
}

void setKickstartCD(struct loaderData_s * loaderData, int argc, char ** argv) {

    logMessage(INFO, "kickstartFromCD");
#if !defined(__s390__) && !defined(__s390x__)
    loaderData->method = METHOD_CDROM;
#endif
}

int kickstartFromCD(char *kssrc) {
    int rc, i;
    char *p, *kspath;
    struct device ** devices;

    logMessage(INFO, "getting kickstart file from first CDROM");

    devices = probeDevices(CLASS_CDROM, BUS_UNSPEC, 0);
    if (!devices) {
        logMessage(ERROR, "No CDROM devices found!");
        return 1;
    }

    /* format is cdrom:[/path/to/ks.cfg] */
    kspath = "";
    p = strchr(kssrc, ':');
    if (p)
        kspath = p + 1;

    if (!p || strlen(kspath) < 1)
        kspath = "/ks.cfg";

    for (i=0; devices[i]; i++) {
        if (!devices[i]->device)
            continue;

        rc = getKickstartFromBlockDevice(devices[i]->device, kspath);
        if (rc == 0)
            return 0;
    }

    startNewt();
    newtWinMessage(_("Error"), _("OK"),
                   _("Cannot find kickstart file on CDROM."));
    return 1;
}

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