source: MondoRescue/branches/3.3/mondo/src/common/libmondo-files.c@ 3866

/* file manipulation
   $Id: libmondo-files.c 3866 2024-03-07 12:55:18Z bruno $
*/

/**
 * @file
 * Functions to manipulate files.
 */


#include "my-stuff.h"
#include "mr_mem.h"
#include "mr_file.h"
#include "mondostructures.h"
#include "libmondo-files.h"

#include "lib-common-externs.h"

#include "libmondo-tools-EXT.h"
#include "libmondo-gui-EXT.h"
#include "libmondo-devices-EXT.h"
#include "libmondo-fork-EXT.h"
#include "libmondo-string-EXT.h"

/*@unused@*/
//static char cvsid[] = "$Id: libmondo-files.c 3866 2024-03-07 12:55:18Z bruno $";

extern char err_log_lines[NOOF_ERR_LINES][MAX_STR_LEN];

extern char *mr_popup_and_get_string(const char *, const char *, const char *);

extern int g_currentY;
extern char *g_mondo_home;

extern bool g_text_mode;

/* Reference to global bkpinfo */
extern struct s_bkpinfo *bkpinfo;

/**
 * @addtogroup fileGroup
 * @{
 */
/**
 * Get an md5 checksum of the specified file.
 * @param filename The file to checksum.
 * @return The 32-character ASCII representation of the 128-bit checksum.
 * @note The returned string points to static storage that will be overwritten with each call.
 */
char *calc_checksum_of_file(char *filename)
{
    /*@ buffers ***************************************************** */
    static char output[MAX_STR_LEN];
    char *command = NULL;

    /*@ pointers **************************************************** */
    char *p = NULL;
    char *q;
    FILE *fin;

    /*@ initialize pointers ***************************************** */

    p = output;

    /*@************************************************************** */

    assert_string_is_neither_NULL_nor_zerolength(filename);
    if (does_file_exist(filename)) {
        mr_asprintf(command, "md5sum \"%s\"", filename);
        fin = popen(command, "r");
        if (fin) {
            q = fgets(output, MAX_STR_LEN, fin);
            if (!q) {
                // FIXME
            }
            q = strchr(output, ' ');
            paranoid_pclose(fin);
        }
        mr_free(command);
    } else {
        log_it("File '%s' not found; cannot calc checksum", filename);
    }
    if (p) {
        *p = '\0';
    }
    return (output);
}


/**
 * Get a not-quite-unique representation of some of the file's @c stat properties.
 * The returned string has the form <tt>size-mtime-ctime</tt>.
 * @param curr_fname The file to generate the "checksum" for.
 * @return The "checksum".
 * @note The returned string points to static storage that will be overwritten with each call.
 */
char *calc_file_ugly_minichecksum(char *curr_fname)
{

    /*@ buffers ***************************************************** */
    static char curr_cksum[1000];

    /*@ pointers **************************************************** */

    /*@ structures ************************************************** */
    struct stat buf;

    /*@ initialize data *************************************************** */
    curr_cksum[0] = '\0';

    /*@************************************************************** */

    assert_string_is_neither_NULL_nor_zerolength(curr_fname);
    if (lstat(curr_fname, &buf)) {
        return (curr_cksum);    // empty
    }

    sprintf(curr_cksum, "%ld-%ld-%ld", (long) (buf.st_size),
            (long) (buf.st_mtime), (long) (buf.st_ctime));
    return (curr_cksum);
}



/**
 * Get the number of lines in @p filename.
 * @param filename The file to count lines in.
 * @return The number of lines in @p filename.
 * @bug This function uses the shell and "wc -l"; it should probably be rewritten in C.
 */
long count_lines_in_file(char *filename)
{

    /*@ buffers ***************************************************** */
    char *command = NULL;
    char *incoming = NULL;

    /*@ long ******************************************************** */
    long noof_lines = -1L;

    /*@ pointers **************************************************** */
    FILE *fin;

    assert_string_is_neither_NULL_nor_zerolength(filename);
    if (!does_file_exist(filename)) {
        log_it("%s does not exist, so I cannot found the number of lines in it", filename);
        return (0);
    }
    mr_asprintf(command, "cat %s | wc -l", filename);
    if (!does_file_exist(filename)) {
        mr_free(command);
        return (-1);
    }
    fin = popen(command, "r");
    mr_free(command);

    if (fin) {
        if (feof(fin)) {
            noof_lines = 0;
        } else {
            mr_getline(incoming, fin);
            while (strlen(incoming) > 0 && incoming[strlen(incoming) - 1] < 32) {
                incoming[strlen(incoming) - 1] = '\0';
            }
            noof_lines = atol(incoming);
            mr_free(incoming);
        }
        paranoid_pclose(fin);
    }
    return (noof_lines);
}


/**
 * Check for existence of given @p filename.
 * @param filename The file to check for.
 * @return TRUE if it exists, FALSE otherwise.
 */
bool does_file_exist(const char *filename)
{

    /*@ structures ************************************************** */
    struct stat buf;

    /*@************************************************************** */

    assert(filename != NULL);
    //  assert_string_is_neither_NULL_nor_zerolength(filename);
    if (lstat(filename, &buf)) {
        log_msg(20, "%s does not exist", filename);
        return (FALSE);
    } else {
        log_msg(20, "%s exists", filename);
        return (TRUE);
    }
}






/**
 * Modify @p inout (a file containing a list of files) to only contain files
 * that exist.
 * @param inout The filelist to operate on.
 * @note The original file is renamed beforehand, so it will not be accessible
 * while the modification is in progress.
 */
void exclude_nonexistent_files(char *inout)
{
    char *infname = NULL;
    char *outfname = NULL;
    char *tmp = NULL;
    char *incoming = NULL;

    /*@ int ********************************************************* */
    int i;

    /*@ pointers **************************************************** */
    FILE *fin, *fout;


    /*@ end vars *********************************************************** */

    assert_string_is_neither_NULL_nor_zerolength(inout);
    mr_asprintf(infname, "%s.in", inout);
    mr_asprintf(tmp, "cp -f %s %s", inout, infname);
    run_program_and_log_output(tmp, FALSE);
    mr_free(tmp);

    if (!(fin = fopen(infname, "r"))) {
        log_OS_error("Unable to openin infname");
        mr_free(infname);
        return;
    }

    mr_asprintf(outfname, "%s", inout);
    if (!(fout = fopen(outfname, "w"))) {
        log_OS_error("Unable to openout outfname");
        mr_free(infname);
        mr_free(outfname);
        return;
    }
    mr_free(outfname);

    for (mr_getline(incoming, fin); !feof(fin); mr_getline(incoming, fin)) {
        i = strlen(incoming) - 1;
        if (i >= 0 && incoming[i] < 32) {
            incoming[i] = '\0';
        }
        if (does_file_exist(incoming)) {
            fprintf(fout, "%s\n", incoming);
        } else {
            log_it("Excluding '%s'-nonexistent\n", incoming);
        }
        mr_free(incoming);
    }
    mr_free(incoming);

    paranoid_fclose(fout);
    paranoid_fclose(fin);
    unlink(infname);
    mr_free(infname);
}


/**
 * Attempt to find the user's kernel by calling Mindi.
 * If Mindi can't find the kernel, ask user. If @p kernel is not empty,
 * don't do anything.
 * @param kernel Where to put the found kernel.
 * @return 0 for success aborts otherwise
 */
int figure_out_kernel_path_interactively_if_necessary(char *kernel)
{
    char *tmp = NULL;
    char *command = NULL;

    if (kernel == NULL) {
        kernel = call_program_and_get_last_line_of_output("mindi --findkernel 2> /dev/null");
    }
    // If we didn't get anything back, check whether mindi raised a fatal error
    if (strcmp(kernel,"") == 0) {
        mr_asprintf(command, "grep 'Fatal error' %s", MINDI_LOGFILE);
        tmp = call_program_and_get_last_line_of_output(command);
        if (strlen(tmp) > 1) {
            popup_and_OK(tmp);
            mr_free(tmp);
            mr_free(command);
            fatal_error("Mindi gave a fatal error. Please check "MINDI_LOGFILE);
        }
        mr_free(tmp);
        mr_free(command);
    } else {
        // If we've found the kernel, allow sysadmin to modify it if he wants
        while ((kernel == NULL) || (strcmp(kernel,"") == 0)) {
            if (!g_text_mode) {
                tmp = mr_popup_and_get_string("Kernel path", "We found this full path name for your kernel. You should just use it in most cases", kernel);
                if (tmp == NULL) {
                    fatal_error("Kernel not found. Please specify with the '-k' flag.");
                } else {
                    mr_free(kernel);
                    kernel = tmp;
                }
            }
        }
    }
    log_it("User says kernel is at %s", kernel);

    log_it("Calling Mindi with kernel path of '%s'", kernel);
    return(0);
}


/**
 * Find location of specified executable in user's PATH.
 * @param fname The basename of the executable to search for (e.g. @c afio).
 * @return The full path to the executable, or NULL if it does not exist, or if @c file could not be found.
 * @note The returned string points to an allocated string that needs to be freed by caller
 * @bug The checks with @c file and @c dirname seem pointless. If @c incoming is "", then you're calling
 * <tt>dirname 2\>/dev/null</tt> or <tt>file 2\>/dev/null | cut -d':' -f1 2\>/dev/null</tt>, which basically amounts
 * to nothing.
 */
char *find_home_of_exe(const char *fname)
{
    /*@ buffers ********************* */
    char *output = NULL;
    char *command = NULL;

    /*@******************************* */

    assert_string_is_neither_NULL_nor_zerolength(fname);

    mr_asprintf(command, "whereis %s 2>/dev/null | awk '{ print $2 }'", fname);
    /* either "" or the string  can't be NULL*/
    output = call_program_and_get_last_line_of_output(command);
    mr_free(command);

    if (output[0] == '\0') {
        mr_asprintf(command, "which %s 2> /dev/null", fname);
        /* either "" or the string  can't be NULL*/
        mr_free(output);
        output = call_program_and_get_last_line_of_output(command);
        mr_free(command);
    }

    if (output[0] != '\0' && does_file_exist(output)) {
        log_msg(4, "find_home_of_exe --- Found %s at %s", fname, output);
        return(output);
    } else {
        log_msg(4, "find_home_of_exe --- Could not find %s", fname);
        return(NULL);
    }
}


/**
 * Get the last sequence of digits surrounded by non-digits in the first 32k of
 * a file.
 * @param logfile The file to look in.
 * @return The number found, or 0 if none.
 */
int get_trackno_from_logfile(char *logfile)
{

    /*@ pointers ********************************************************* */
    FILE *fin;

    /*@ int ************************************************************** */
    int trackno = 0;
    size_t len = 0;

    /*@ buffer ************************************************************ */
    char datablock[32701];

    assert_string_is_neither_NULL_nor_zerolength(logfile);
    if (!(fin = fopen(logfile, "r"))) {
        log_OS_error("Unable to open logfile");
        fatal_error("Unable to open logfile to read trackno");
    }
    len = fread(datablock, 1, 32700, fin);
    paranoid_fclose(fin);
    if (len <= 0) {
        return (0);
    }
    for (; len > 0 && !isdigit(datablock[len - 1]); len--);
    datablock[len--] = '\0';
    for (; len > 0 && isdigit(datablock[len - 1]); len--);
    trackno = atoi(datablock + len);
    return (trackno);
}







/**
 * Get a percentage from the last line of @p filename. We look for the string
 * "% done" on the last line and, if we find it, grab the number before the last % sign.
 * @param filename The file to get the percentage from.
 * @return The percentage found, or 0 for error.
 */
int grab_percentage_from_last_line_of_file(char *filename)
{

    /*@ buffers ***************************************************** */
    char *lastline = NULL;
    char *command = NULL;
    /*@ pointers **************************************************** */
    char *p = NULL;

    /*@ int's ******************************************************* */
    int i = 0;

    for (i = NOOF_ERR_LINES - 1; i >= 0 && !strstr(err_log_lines[i], "% Done") && !strstr(err_log_lines[i], "% done"); i--);
    if (i < 0) {
        mr_asprintf(command, "tail -n3 %s | grep -Fi \"%c\" | tail -n1 | awk '{print $0;}'", filename, '%');
        lastline = call_program_and_get_last_line_of_output(command);
        mr_free(command);
        if (!lastline[0]) {
            mr_free(lastline);
            return(0);
        }
    } else {
        mr_asprintf(lastline, "%s", err_log_lines[i]);
    }

    p = strrchr(lastline, '%');
    if (p) {
        *p = '\0';
    } else {
        mr_free(lastline);
        return(0);
    }

    for (p--; isdigit(*p) && p != lastline; p--);
    if (p != lastline) {
        p++;
    }
    i = atoi(p);
    mr_free(lastline);
    return(i);
}





/**
 * Return the last line of @p filename.
 * @param filename The file to get the last line of.
 * @return The last line of the file.
 * @note The returned string points to static storage that will be overwritten with each call.
 */
char *last_line_of_file(char *filename)
{
    /*@ buffers ***************************************************** */
    static char output[MAX_STR_LEN];
    char *command = NULL;
    char *p = NULL;

    /*@ pointers **************************************************** */
    FILE *fin;

    /*@ end vars **************************************************** */

    if (!does_file_exist(filename)) {
        log_it("Trying to get last line of nonexistent file (%s)", filename);
        output[0] = '\0';
        return (output);
    }
    mr_asprintf(command, "tail -n1 %s", filename);
    fin = popen(command, "r");
    mr_free(command);
    p = fgets(output, MAX_STR_LEN, fin);
    if (p == NULL) {
        // FIXME
    }
    paranoid_pclose(fin);
    while (strlen(output) > 0 && output[strlen(output) - 1] < 32) {
        output[strlen(output) - 1] = '\0';
    }
    return(output);
}

/**
 * Get the length of @p filename in bytes.
 * @param filename The file to get the length of.
 * @return The length of the file, or -1 for error.
 */
off_t length_of_file(char *filename)
{
    /*@ pointers *************************************************** */
    FILE *fin;

    /*@ long long ************************************************* */
    off_t length;

    fin = fopen(filename, "r");
    if (!fin) {
        log_it("filename=%s", filename);
        log_OS_error("Unable to openin filename");
        return(-1);
    }
    fseeko(fin, 0, SEEK_END);
    length = ftello(fin);
    paranoid_fclose(fin);
    return(length);
}



/**
 * ?????
 * @bug I don't know what this function does. However, it seems orphaned, so it should probably be removed.
 */
int make_checksum_list_file(char *filelist, char *cksumlist, char *comppath) {
    /*@ pointers **************************************************** */
    FILE *fin;
    FILE *fout;

    /*@ int   ******************************************************* */
    int percentage;
    int i;
    int counter = 0;

    /*@ buffer ****************************************************** */
    char *stub_fname = NULL;
    char *curr_fname = NULL;
    char *curr_cksum = NULL;
    char *tmp = NULL;

    /*@ long [long] ************************************************* */
    off_t filelist_length;
    off_t curr_pos;
    long start_time;
    long current_time;
    long time_taken;
    long time_remaining;

    /*@ end vars *************************************************** */

    start_time = get_time();
    filelist_length = length_of_file(filelist);
    log_it("filelist = %s; cksumlist = %s", filelist, cksumlist);

    fin = fopen(filelist, "r");
    if (fin == NULL) {
        log_OS_error("Unable to fopen-in filelist");
        log_to_screen("Can't open filelist");
        return(1);
    }
    fout = fopen(cksumlist, "w");
    if (fout == NULL) {
        log_OS_error("Unable to openout cksumlist");
        paranoid_fclose(fin);
        log_to_screen("Can't open checksum list");
        return(1);
    }
    for (mr_getline(stub_fname, fin); !feof(fin); mr_getline(stub_fname, fin)) {
        i = strlen(stub_fname) - 1;
        if (stub_fname[i] < 32) {
            stub_fname[i] = '\0';
        }
        mr_asprintf(tmp, "%s%s", comppath, stub_fname);
        mr_free(stub_fname);

        mr_asprintf(curr_fname, "%s", tmp + 1);
        mr_free(tmp);

        mr_asprintf(curr_cksum, "%s", calc_file_ugly_minichecksum(curr_fname));
        fprintf(fout, "%s\t%s\n", curr_fname, curr_cksum);
        mr_free(curr_cksum);

        if (counter++ > 12) {
            current_time = get_time();
            counter = 0;
            /* TODO: 37 really ? */
            curr_fname[37] = '\0';
            curr_pos = ftello(fin) / 1024;
            percentage = (int) (curr_pos * 100 / filelist_length);
            time_taken = current_time - start_time;
            if (percentage != 0) {
                time_remaining = time_taken * 100 / (long) (percentage) - time_taken;
                log_to_screen("%02d%% done   %02d:%02d taken   %02d:%02d remaining  %-37s\r", percentage, (int) (time_taken / 60), (int) (time_taken % 60), (int) (time_remaining / 60), (int) (time_remaining % 60), curr_fname);
            }
            sync();
        }
        mr_free(curr_fname);
    }
    mr_free(stub_fname);

    paranoid_fclose(fout);
    paranoid_fclose(fin);
    log_it("Done.");
    return(0);
}


/**
 * Create the directory @p outdir_fname and all parent directories. Equivalent to <tt>mkdir -p</tt>.
 * @param outdir_fname The directory to create.
 * @return The return value of @c mkdir.
 */
int make_hole_for_dir(const char *outdir_fname)
{
    char *tmp = NULL;
    int res = 0;

    assert_string_is_neither_NULL_nor_zerolength(outdir_fname);
    mr_asprintf(tmp, "mkdir -p %s", outdir_fname);
    res = system(tmp);
    mr_free(tmp);
    return(res);
}


/**
 * Create the parent directories of @p outfile_fname.
 * @param outfile_fname The file to make a "hole" for.
 * @return 0, always.
 * @bug Return value unnecessary.
 */
int make_hole_for_file(char *outfile_fname)
{
    /*@ buffer ****************************************************** */
    char *command = NULL;

    /*@ int  ******************************************************** */
    int res = 0;

    /*@ end vars *************************************************** */

    assert_string_is_neither_NULL_nor_zerolength(outfile_fname);
    assert(!strstr(outfile_fname, MNT_CDROM));
    assert(!strstr(outfile_fname, "/dev/cdrom"));
    mr_asprintf(command, "mkdir -p \"%s\" 2> /dev/null", outfile_fname);
    res += system(command);
    mr_free(command);

    mr_asprintf(command, "rmdir \"%s\" 2> /dev/null", outfile_fname);
    res += system(command);
    mr_free(command);

    mr_asprintf(command, "rm -f \"%s\" 2> /dev/null", outfile_fname);
    res += system(command);
    mr_free(command);

    unlink(outfile_fname);
    return(0);
}


/**
 * Get the number of lines in @p filelist_fname that contain the string @p wildcard.
 * @param filelist_fname The file to search through.
 * @param wildcard The string to search for. This is @e not a shell glob or a regular expression.
 * @return The number of lines matched.
 */
long noof_lines_that_match_wildcard(char *filelist_fname, char *wildcard)
{
    /*@ long ******************************************************* */
    long matches = 0;

    /*@ pointers *************************************************** */
    FILE *fin;

    /*@ buffers **************************************************** */
    char *incoming = NULL;

    /*@ end vars *************************************************** */


    fin = fopen(filelist_fname, "r");

    if (!fin) {
        log_OS_error("Unable to openin filelist_fname");
        return(0);
    }
    mr_getline(incoming, fin);
    while (!feof(fin)) {
        if (strstr(incoming, wildcard)) {
            matches++;
        }
        mr_free(incoming);
        mr_getline(incoming, fin);
    }
    mr_free(incoming);
    paranoid_fclose(fin);
    return(matches);
}



/**
 * Determine the size (in KB) of @p dev in the mountlist in <tt>tmpdir</tt>/mountlist.txt.
 * @param tmpdir The tempdir where the mountlist is stored.
 * @param dev The device to search for.
 * @return The size of the partition in KB.
 */
long size_of_partition_in_mountlist_K(char *tmpdir, char *dev)
{
    char *command = NULL;
    char *mountlist = NULL;
    char *sz_res = NULL;
    long file_len_K;

    mr_asprintf(mountlist, "%s/mountlist.txt", tmpdir);
    mr_asprintf(command, "grep \"%s \" %s/mountlist.txt | head -n1 | awk '{print $4}'", dev, tmpdir);
    mr_free(mountlist);

    log_it(command);
    sz_res = call_program_and_get_last_line_of_output(command);
    file_len_K = atol(sz_res);
    log_msg(4, "%s --> %s --> %ld", command, sz_res, file_len_K);
    mr_free(sz_res);
    mr_free(command);

    return(file_len_K);
}

/**
 * Calculate the total size (in KB) of all the biggiefiles in this backup.
 * @param bkpinfo The backup information structure. Only the @c bkpinfo->tmpdir field is used.
 * @return The total size of all biggiefiles in KB.
 */
long size_of_all_biggiefiles_K()
{
    /*@ buffers ***************************************************** */
    char *fname = NULL;
    char *biggielist = NULL;
    char *tmp = NULL;
    char *command = NULL;

    /*@ long ******************************************************** */
    long scratchL = 0;
    long file_len_K;

    /*@ pointers *************************************************** */
    FILE *fin = NULL;

    /*@ end vars *************************************************** */

    log_it("Calculating size of all biggiefiles (in total)");
    mr_asprintf(biggielist, "%s/biggielist.txt", bkpinfo->tmpdir);
    log_it("biggielist = %s", biggielist);
    fin = fopen(biggielist, "r");
    mr_free(biggielist);

    if (!(fin)) {
        log_OS_error("Cannot open biggielist. OK, so estimate is based on filesets only.");
    } else {
        log_msg(4, "Reading it...");
        for (mr_getline(fname, fin); !feof(fin); mr_getline(fname, fin)) {
            if (fname[strlen(fname) - 1] <= 32) {
                fname[strlen(fname) - 1] = '\0';
            }
            if (0 == strncmp(fname, "/dev/", 5)) {
                if (is_dev_an_NTFS_dev(fname)) {
                    if ((tmp = find_home_of_exe("ntfsresize")) == NULL) {
                        mr_free(tmp);
                        mr_free(fname);
                        fatal_error("ntfsresize not found");
                    }
                    mr_asprintf(command, "%s --force --info %s|grep '^You might resize at '|cut -d' ' -f5", tmp, fname);
                    mr_free(tmp);
                    log_it("command = %s", command);
                    tmp = call_program_and_get_last_line_of_output(command);
                    mr_free(command);

                    log_it("res of it = %s", tmp);
                    file_len_K = atoll(tmp) / 1024L;
                    mr_free(tmp);
                } else {
                    file_len_K = get_phys_size_of_drive(fname) * 1024L;
                }
            } else {
                /* TODO: more than long here ??? */
                file_len_K = (long) (length_of_file(fname) / 1024);
            }
            if (file_len_K > 0) {
                scratchL += file_len_K;
                log_msg(4, "%s --> %ld K", fname, file_len_K);
            }
            log_msg(4, "After adding %s, scratchL+%ld now equals %ld", fname, file_len_K, scratchL);
            if (feof(fin)) {
                break;
            }
            mr_free(fname);
        }
        mr_free(fname);
    }
    log_it("Closing...");
    paranoid_fclose(fin);
    log_it("Finished calculating total size of all biggiefiles");
    log_it("Total size of all biggiefiles = %ld Kb", scratchL);
    return(scratchL);
}

/**
 * Determine the amount of space (in KB) occupied by a mounted CD.
 * This can also be used to find the space used for other directories.
 * @param mountpt The mountpoint/directory to check.
 * @return The amount of space occupied in KB.
 */
long long space_occupied_by_cd(char *mountpt)
{
    /*@ buffer ****************************************************** */
    char *tmp = NULL;
    char *command = NULL;
    long long llres;
    /*@ pointers **************************************************** */
    char *p;
    FILE *fin;

    /*@ end vars *************************************************** */

    mr_asprintf(command, "du -sk %s", mountpt);
    errno = 0;
    fin = popen(command, "r");
    if (errno) {
      log_it("popen() FAILED: command=%s, mountpt=%s, fin=%d, errno=%d, strerror=%s", command, mountpt, fin, errno, strerror(errno));
      llres = 0;
    } else {
      mr_getline(tmp, fin);
      paranoid_pclose(fin);
      p = strchr(tmp, '\t');
      if (p) {
        *p = '\0';
      }
      for (p = tmp, llres = 0; *p != '\0'; p++) {
        llres *= 10;
        llres += (int) (*p - '0');
      }
      mr_free(tmp);
    }
    mr_free(command);

    return(llres);
}


/**
 * Update a CRC checksum to include another character.
 * @param crc The original CRC checksum.
 * @param c The character to add.
 * @return The new CRC checksum.
 * @ingroup utilityGroup
 */
unsigned int updcrc(unsigned int crc, unsigned int c)
{
    unsigned int tmp;
    tmp = (crc >> 8) ^ c;
    crc = (crc << 8) ^ crctttab[tmp & 255];
    return(crc);
}

/**
 * Update a reverse CRC checksum to include another character.
 * @param crc The original CRC checksum.
 * @param c The character to add.
 * @return The new CRC checksum.
 * @ingroup utilityGroup
 */
unsigned int updcrcr(unsigned int crc, unsigned int c)
{
    unsigned int tmp;
    tmp = crc ^ c;
    crc = (crc >> 8) ^ crc16tab[tmp & 0xff];
    return(crc);
}




/**
 * Check for an executable on the user's system; write a message to the
 * screen and the log if we can't find it.
 * @param fname The executable basename to look for.
 * @return 0 if it's found, nonzero if not.
 */
int whine_if_not_found(char *fname)
{
    /*@ buffers *** */
    char *tmp = NULL;

    tmp = find_home_of_exe(fname);
    if (tmp == NULL) {
        log_to_screen("Please install '%s'. I cannot find it on your system.", fname);
        return(1);
    } else {
        mr_free(tmp);
        return(0);
    }
}



/**
 * Create a data file at @p fname containing @p contents.
 * The data actually can be multiple lines, despite the name.
 * @param fname The file to create.
 * @param contents The data to put in it.
 * @return 0 for success, 1 for failure.
 */
int write_one_liner_data_file(char *fname, char *contents)
{
    /*@ pointers *************************************************** */
    FILE *fout;
    int res = 0;

    /*@ end vars *************************************************** */

    assert_string_is_neither_NULL_nor_zerolength(fname);
    if (!contents) {
        log_it("%d: Warning - writing NULL to %s", __LINE__, fname);
    }
    if (!(fout = fopen(fname, "w"))) {
        log_it("fname=%s");
        log_OS_error("Unable to openout fname");
        return (1);
    }
    fprintf(fout, "%s\n", contents);
    paranoid_fclose(fout);
    return (res);
}



/**
 * Read @p fname into @p contents.
 * @param fname The file to read.
 * @param contents Where to put its contents.
 * @return 0 for success, nonzero for failure.
 */
int read_one_liner_data_file(char *fname, char *contents)
{
    /*@ pointers *************************************************** */
    FILE *fin;
    int res = 0;
    int i;

    /*@ end vars *************************************************** */

    assert_string_is_neither_NULL_nor_zerolength(fname);
    if (!contents) {
        log_it("%d: Warning - reading NULL from %s", __LINE__, fname);
    }
    if (!(fin = fopen(fname, "r"))) {
        log_it("fname=%s", fname);
        log_OS_error("Unable to openin fname");
        return(1);
    }
    res = fscanf(fin, "%s\n", contents);
    i = strlen(contents);
    if (i > 0 && contents[i - 1] < 32) {
        contents[i - 1] = '\0';
    }
    paranoid_fclose(fin);
    res = 0;
    return(res);
}






/**
 * Copy the files that Mondo/Mindi need to run to the scratchdir or tempdir.
 * Currently this includes: copy Mondo's home directory to scratchdir, untar "mondo_home/payload.tgz"
 * if it exists, copy LAST-FILELIST-NUMBER to scratchdir, copy mondorestore
 * and post-nuke.tgz (if it exists) to tmpdir, and run "hostname > scratchdir/HOSTNAME".
 * @param bkpinfo The backup information structure. Fields used:
 * - @c bkpinfo->postnuke_tarball
 * - @c bkpinfo->scratchdir
 * - @c bkpinfo->tmpdir
 */
void copy_mondo_and_mindi_stuff_to_scratchdir()
{
    /*@ Char buffers ** */
    char *command = NULL;
    char *tmp = NULL;
    char *old_pwd = NULL;
    int res = 0;

    mvaddstr_and_log_it(g_currentY, 0, "Copying Mondo's core files to the scratch directory");

    log_msg(4, "g_mondo_home='%s'", g_mondo_home);
    if (strlen(g_mondo_home) < 2) {
        find_and_store_mondoarchives_home(g_mondo_home);
    }
    mr_asprintf(command, CP_BIN " --parents -pRdf %s %s", g_mondo_home, bkpinfo->scratchdir);

    log_msg(4, "command = %s", command);
    res = run_program_and_log_output(command, 1);
    mr_free(command);

    if (res) {
        fatal_error("Failed to copy Mondo's stuff to scratchdir");
    }

    mr_asprintf(tmp, "%s/payload.tgz", g_mondo_home);
    if (does_file_exist(tmp)) {
        log_it("Untarring payload %s to scratchdir %s", tmp, bkpinfo->scratchdir);
        old_pwd = mr_getcwd();
        if (chdir(bkpinfo->scratchdir)) {
            // FIXME
        }
        mr_asprintf(command, "tar -zxvf %s", tmp);
        res = run_program_and_log_output(command, FALSE);
        if (res) {
            mr_free(command);
            mr_free(tmp);
            fatal_error("Failed to untar payload");
        }
        mr_free(command);
        if (chdir(old_pwd)) {
            // FIXME
        }
        mr_free(old_pwd);
    }
    mr_free(tmp);

    mr_asprintf(command, "cp -f %s/LAST-FILELIST-NUMBER %s", bkpinfo->tmpdir, bkpinfo->scratchdir);

    if (run_program_and_log_output(command, FALSE)) {
        fatal_error("Failed to copy LAST-FILELIST-NUMBER to scratchdir");
    }
    mr_free(command);

    tmp = call_program_and_get_last_line_of_output("which mondorestore");
    if (!tmp[0]) {
        mr_free(tmp);
        fatal_error("'which mondorestore' returned null. Where's your mondorestore? `which` can't find it. That's odd. Did you install mondorestore?");
    }

    mr_asprintf(command, "cp -f %s %s", tmp, bkpinfo->tmpdir);
    mr_free(tmp);
    res = run_program_and_log_output(command, FALSE);
    if (res) {
        mr_free(command);
        fatal_error("Failed to copy mondorestore to tmpdir");
    }
    mr_free(command);

    mr_asprintf(command, "hostname > %s/HOSTNAME", bkpinfo->scratchdir);
    paranoid_system(command);
    mr_free(command);

    if (bkpinfo->postnuke_tarball != NULL) {
        mr_asprintf(command, "cp -f %s %s/post-nuke.tgz", bkpinfo->postnuke_tarball, bkpinfo->tmpdir);
        res = run_program_and_log_output(command, FALSE);
        mr_free(command);

        if (res) {
            fatal_error("Unable to copy post-nuke tarball to tmpdir");
        }
    }

    mvaddstr_and_log_it(g_currentY++, 74, "Done.");
}


/**
 * Determine the approximate number of media that the backup will take up,
 * and tell the user. The uncompressed size is estimated as size_of_all_biggiefiles_K()
 * plus (noof_sets x bkpinfo->optimal_set_size). The compression factor is estimated as
 * 2/3 for LZO and 1/2 for bzip2. The data is not saved anywhere. If there are any
 * "imagedevs", the estimate is not shown as it will be wildly inaccurate.
 * If there are more than 50 media estimated, the estimate will not be shown.
 * @param bkpinfo The backup information structure. Fields used:
 * - @c bkpinfo->backup_media_type
 * - @c bkpinfo->media_size
 * - @c bkpinfo->optimal_set_size
 * - @c bkpinfo->use_lzo
 * @param noof_sets The number of filesets created.
 * @ingroup archiveGroup
 */
void
estimate_noof_media_required(long noof_sets)
{
    /*@ buffers *************** */
    char *tmp = NULL;
    char *tmp1 = NULL;
    char *mds = NULL;

    /*@ long long ************* */
    long long scratchLL;

    if (bkpinfo->media_size <= 0) {
        log_to_screen("Number of media required: UNKNOWN");
        return;
    }

    log_it("Estimating number of media required...");
    scratchLL = (long long) (noof_sets) * (long long) (bkpinfo->optimal_set_size) + (long long) (size_of_all_biggiefiles_K());
    scratchLL = (scratchLL / 1024) / bkpinfo->media_size;
    scratchLL++;
    if (bkpinfo->use_lzo) {
        scratchLL = (scratchLL * 2) / 3;
    } else if (bkpinfo->use_gzip) {
        scratchLL = (scratchLL * 2) / 3;
    } else if (bkpinfo->use_lzma) {
        scratchLL = (scratchLL * 2) / 3;
    } else {
        scratchLL = scratchLL / 2;
    }
    if (!scratchLL) {
        scratchLL++;
    }
    tmp1 = number_to_text((int) (scratchLL + 1));
    if (scratchLL <= 1) {
        mds = media_descriptor_string(bkpinfo->backup_media_type);
        mr_asprintf(tmp, "Your backup will probably occupy a single %s. Maybe two.", mds);
        mr_free(mds);
    } else if (scratchLL > 5) {
        mr_asprintf(tmp, "Your backup will occupy one meeeeellion media! (maybe %s)", tmp1);
    } else {
        mr_asprintf(tmp, "Your backup will occupy approximately %s media.", tmp1);
    }
    if (scratchLL < 50) {
        log_to_screen(tmp);
    }
    mr_free(tmp1);
    mr_free(tmp);
}


/**
 * Determine whether a file is compressed. This is done
 * by reading through the "do-not-compress-these" file distributed with Mondo.
 * @param filename The file to check.
 * @return TRUE if it's compressed, FALSE if not.
 */
bool is_this_file_compressed(char *filename)
{
    char *do_not_compress_these = NULL;
    char *tmp = NULL;
    char *p;
    char *q = NULL;

    q = strrchr(filename, '.');
    if (q == NULL) {
        return (FALSE);
    }

    mr_asprintf(tmp, "%s/do-not-compress-these", g_mondo_home);
    if (!does_file_exist(tmp)) {
        mr_free(tmp);
        return (FALSE);
    }
    /* TODO: This is just plain WRONG !! */
    mr_asprintf(do_not_compress_these,"%s", last_line_of_file(tmp));
    mr_free(tmp);

    for (p = do_not_compress_these; p != NULL; p++) {
        mr_asprintf(tmp, "%s", p);
        if (strchr(tmp, ' ')) {
            *(strchr(tmp, ' ')) = '\0';
        }
        if (!strcmp(q, tmp)) {
            mr_free(tmp);
            mr_free(do_not_compress_these);
            return (TRUE);
        }
        if (!(p = strchr(p, ' '))) {
            break;
        }
        mr_free(tmp);
    }
    mr_free(do_not_compress_these);
    return (FALSE);
}

/* @} - end fileGroup */