method.c

linux 安装程序

/*
 * method.c - generic install method setup functions
 *
 * Erik Troan <[e-mail]>
 * Matt Wilson <[e-mail]>
 * Michael Fulbright <[e-mail]>
 * Jeremy Katz <[e-mail]>
 *
 * Copyright 2002 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 <inttypes.h>
#include <libgen.h>
#include <newt.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/types.h>
#include <unistd.h>
#include <libgen.h>

#include "loader.h"
#include "loadermisc.h"
#include "log.h"
#include "lang.h"
#include "mediacheck.h"
#include "method.h"

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

#include "devt.h"

#include "nfsinstall.h"
#include "hdinstall.h"
#include "urlinstall.h"

/* boot flags */
extern int flags;

int umountLoopback(char * mntpoint, char * device) {
    int loopfd;

    umount(mntpoint);

    logMessage(INFO, "umounting loopback %s %s", mntpoint, device);

    devMakeInode(device, "/tmp/loop");
    loopfd = open("/tmp/loop", O_RDONLY);

    if (ioctl(loopfd, LOOP_CLR_FD, 0) == -1)
        logMessage(ERROR, "LOOP_CLR_FD failed for %s %s (%s)", mntpoint,
                   device, strerror(errno));

    close(loopfd);

    return 0;
}


int mountLoopback(char * fsystem, char * mntpoint, char * device) {
    struct loop_info loopInfo;
    int targfd, loopfd;
    char *filename;

    mkdirChain(mntpoint);
    filename = alloca(15 + strlen(device));
    sprintf(filename, "/tmp/%s", device);

    mkdirChain(mntpoint);

#ifdef O_DIRECT
    targfd = open(fsystem, O_RDONLY | O_DIRECT);
    if (targfd == -1) {
#endif
	targfd = open(fsystem, O_RDONLY);
	if (targfd == -1) {
	    logMessage(ERROR, "open file to loop mount %s failed", fsystem);
	    return LOADER_ERROR;
	}
#ifdef O_DIRECT
    }
#endif

    devMakeInode(device, filename);
    loopfd = open(filename, O_RDONLY);
    if (loopfd == -1) {
	logMessage(ERROR, "unable to open loop device %s", filename);
	return LOADER_ERROR;
    }
    logMessage(INFO, "mntloop %s on %s as %s fd is %d", 
               device, mntpoint, fsystem, loopfd);

    if (ioctl(loopfd, LOOP_SET_FD, targfd)) {
        logMessage(ERROR, "LOOP_SET_FD failed: %s", strerror(errno));
        ioctl(loopfd, LOOP_CLR_FD, 0);
        close(targfd);
        close(loopfd);
        return LOADER_ERROR;
    }

    close(targfd);

    memset(&loopInfo, 0, sizeof(loopInfo));
    strncpy(loopInfo.lo_name, basename(fsystem), 63);

    if (ioctl(loopfd, LOOP_SET_STATUS, &loopInfo)) {
        logMessage(ERROR, "LOOP_SET_STATUS failed: %s", strerror(errno));
        close(loopfd);
        return LOADER_ERROR;
    }

    close(loopfd);

    /* FIXME: really, mountLoopback() should take a list of "valid" 
     * filesystems for the specific type of image being mounted */
    if (doPwMount(filename, mntpoint, "iso9660", IMOUNT_RDONLY, NULL)) {
        if (doPwMount(filename, mntpoint, "ext2", IMOUNT_RDONLY, NULL)) {
          if (doPwMount(filename, mntpoint, "squashfs", IMOUNT_RDONLY, NULL)) {
            if (doPwMount(filename, mntpoint, "cramfs", IMOUNT_RDONLY, NULL)) {
              if (doPwMount(filename, mntpoint, "vfat", IMOUNT_RDONLY, NULL)) {
                logMessage(ERROR, "failed to mount loop: %s", strerror(errno));
                loopfd = open(filename, O_RDONLY);
                ioctl(loopfd, LOOP_CLR_FD, 0);
                close(loopfd);
                return LOADER_ERROR;
              }
            }
          }
        }
    }

    return 0;
}

/* returns the *absolute* path (malloced) to the #1 iso image */
char * validIsoImages(char * dirName, int *foundinvalid) {
    DIR * dir;
    struct dirent * ent;
    char isoImage[1024];

    if (!(dir = opendir(dirName))) {
        newtWinMessage(_("Error"), _("OK"), 
                   _("Failed to read directory %s: %s"),
                   dirName, strerror(errno));
        return 0;
    }

    /* Walk through the directories looking for a CD image. */
    errno = 0;
    while ((ent = readdir(dir))) {
        snprintf(isoImage, sizeof(isoImage), "%s/%s", dirName, ent->d_name);
        
        if (!fileIsIso(isoImage)) {
            errno = 0;
            continue;
        }
        
        if (mountLoopback(isoImage, "/tmp/loopimage", "loop7")) {
            logMessage(WARNING, "failed to mount %s", isoImage);
            errno = 0;
            continue;
        }
        
	if (mountLoopback("/tmp/loopimage/images/stage2.img", "/mnt/runtime", "loop0")) {
	    umountLoopback("/mnt/runtime", "loop0");
	} else {
	    if (verifyStamp("/mnt/runtime")) {
		umountLoopback("/mnt/runtime", "loop0");
		umountLoopback("/tmp/loopimage", "loop7");
		break;
	    }
	    logMessage(ERROR, "disc %s is not the right image", isoImage);
	    umountLoopback("/mnt/runtime", "loop0");
	    if (foundinvalid) *foundinvalid = 1;
	}
        
        umountLoopback("/tmp/loopimage", "loop7");
        
        errno = 0;
    }
    
    closedir(dir);

    if (!ent) return NULL;

    return strdup(isoImage);
}

/* get timestamp and description of ISO image from stamp file */
/* returns 0 on success, -1 otherwise                         */
int readStampFileFromIso(char *file, char **timestamp, char **releasedescr) {
    DIR * dir;
    FILE *f;
    struct dirent * ent;
    struct stat sb;
    char *stampfile;
    char *descr, *tstamp;
    char tmpstr[1024];
    int  filetype;
    int  rc;

    lstat(file, &sb);
    if (S_ISBLK(sb.st_mode)) {
	filetype = 1;
	if (doPwMount(file, "/tmp/testmnt", "iso9660", IMOUNT_RDONLY, NULL)) {
	    logMessage(ERROR, "Failed to mount device %s to get description",
                       file);
	    return -1;
	}
    } else if (S_ISREG(sb.st_mode)) {
	filetype = 2;
	if (mountLoopback(file, "/tmp/testmnt", "loop6")) {
	    logMessage(ERROR, "Failed to mount iso %s to get description",
                       file);
	    return -1;
	}
    } else {
	    logMessage(ERROR, "Unknown type of file %s to get description",
                       file);
	    return -1;
    }

    if (!(dir = opendir("/tmp/testmnt"))) {
	umount("/tmp/testmnt");
	if (filetype == 2)
	    umountLoopback("/tmp/testmnt", "loop6");
	return -1;
    }

    errno = 0;
    stampfile = NULL;
    while ((ent = readdir(dir))) {
	if (!strncmp(ent->d_name, ".discinfo", 9)) {
	    stampfile = strdup(".discinfo");
	    break;
	}
    }

    closedir(dir);
    descr = NULL;
    tstamp = NULL;
    if (stampfile) {
	snprintf(tmpstr, sizeof(tmpstr), "/tmp/testmnt/%s", stampfile);
	f = fopen(tmpstr, "r");
	if (f) {
	    char *tmpptr;

	    /* readtime stamp line */
	    tmpptr = fgets(tmpstr, sizeof(tmpstr), f);
	    
	    if (tmpptr)
		tstamp = strdup(tmpstr);

	    /* now read OS description line */
	    if (tmpptr)
		tmpptr = fgets(tmpstr, sizeof(tmpstr), f);

	    if (tmpptr)
		descr = strdup(tmpstr);

	    /* skip over arch */
	    if (tmpptr)
		tmpptr = fgets(tmpstr, sizeof(tmpstr), f);

	    /* now get the CD number */
	    if (tmpptr) {
		unsigned int len;
		char *p, *newstr;

		tmpptr = fgets(tmpstr, sizeof(tmpstr), f);
		
		/* nuke newline from end of descr, stick number on end*/
		for (p=descr+strlen(descr); p != descr && !isspace(*p); p--);

		*p = '\0';
		len = strlen(descr) + strlen(tmpstr) + 10;
		newstr = malloc(len);
		strncpy(newstr, descr, len-1);
		strncat(newstr, " ", len-1);

		/* is this a DVD or not?  If disc id has commas, like */
		/* "1,2,3", its a DVD                                 */
		if (strchr(tmpstr, ','))
		    strncat(newstr, "DVD\n", len-1);
		else {
		    strncat(newstr, "disc ", len-1);
		    strncat(newstr, tmpstr, len-1);
		}

		free(descr);
		descr = newstr;
	    }

	    fclose(f);
	}
    }

    free(stampfile);

    umount("/tmp/testmnt");
    if (filetype == 2)
	umountLoopback("/tmp/testmnt", "loop6");

    if (descr != NULL && tstamp != NULL) {
	descr[strlen(descr)-1] = '\0';
	*releasedescr = descr;

	tstamp[strlen(tstamp)-1] = '\0';
	*timestamp = tstamp;

	rc = 0;
    } else {
	rc = 1;
    }	

    return rc;
}

/* XXX this ignores "location", which should be fixed
 *
 * Given a starting isoFile, will offer choice to mediacheck it and
 * all other ISO images in the same directory with the same stamp
 */
void queryIsoMediaCheck(char *isoFile) {
    DIR * dir;
    struct dirent * ent;
    char *isoDir;
    char isoImage[1024];
    char tmpmessage[1024];
    char *master_timestamp;
    char *tmpstr;
    int rc, first;

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

    /* if they did not specify to mediacheck explicitely then return */
    if (!FL_MEDIACHECK(flags))
	return;

    /* check that file is actually an iso */
    if (!fileIsIso(isoFile))
	return;

    /* get stamp of isoFile, free descr since we dont care */
    readStampFileFromIso(isoFile, &master_timestamp, &tmpstr);
    free(tmpstr);
    
    /* get base path from isoFile */
    tmpstr = strdup(isoFile);
    isoDir = strdup(dirname(tmpstr));
    free(tmpstr);

    logMessage(DEBUGLVL, "isoFile = %s", isoFile);
    logMessage(DEBUGLVL, "isoDir  = %s", isoDir);
    logMessage(DEBUGLVL, "Master Timestemp = %s", master_timestamp);

    if (!(dir = opendir(isoDir))) {
	newtWinMessage(_("Error"), _("OK"), 
		       _("Failed to read directory %s: %s"),
		       isoDir, strerror(errno));
	free(isoDir);
	free(master_timestamp);