flexos.c

完整的解压zip文件的源码。包含密码功能

        switch (workch) {
            case '/':             /* can assume -j flag not given */
                *pp = '\0';
                map2fat(pathcomp, last_dot);   /* 8.3 truncation (in place) */
                last_dot = (char *)NULL;
                if ((error = checkdir(__G__ pathcomp, APPEND_DIR)) > 1)
                    return error;
                pp = pathcomp;    /* reset conversion buffer for next piece */
                lastsemi = (char *)NULL; /* leave directory semi-colons alone */
                break;

            /* drive names are not stored in zipfile, so no colons allowed;
             *  no brackets or most other punctuation either (all of which
             *  can appear in Unix-created archives; backslash is particularly
             *  bad unless all necessary directories exist) */
            case '[':          /* these punctuation characters forbidden */
            case ']':          /*  only on plain FAT file systems */
            case '+':
            case ',':
            case '=':
            case ':':           /* special shell characters of command.com */
            case '\\':          /*  (device and directory limiters, wildcard */
            case '"':           /*  characters, stdin/stdout redirection and */
            case '<':           /*  pipe indicators and the quote sign) are */
            case '>':           /*  never allowed in filenames on (V)FAT */
            case '|':
            case '*':
            case '?':
                *pp++ = '_';
                break;

            case '.':
                if (pp == pathcomp) {     /* nothing appended yet... */
                    if (*cp == '/') {     /* don't bother appending a "./" */
                        ++cp;             /*  component to the path:  skip */
                        break;            /*  to next char after the '/' */
                    } else if (*cp == '.' && cp[1] == '/') {   /* "../" */
                        *pp++ = '.';      /* add first dot, unchanged... */
                        ++cp;             /* skip second dot, since it will */
                    } else {              /*  be "added" at end of if-block */
                        *pp++ = '_';      /* FAT doesn't allow null filename */
                        dotname = TRUE;   /*  bodies, so map .exrc -> _.exrc */
                    }                     /*  (extra '_' now, "dot" below) */
                } else if (dotname) {     /* found a second dot, but still */
                    dotname = FALSE;      /*  have extra leading underscore: */
                    *pp = '\0';           /*  remove it by shifting chars */
                    pp = pathcomp + 1;    /*  left one space (e.g., .p1.p2: */
                    while (pp[1]) {       /*  __p1 -> _p1_p2 -> _p1.p2 when */
                        *pp = pp[1];      /*  finished) [opt.:  since first */
                        ++pp;             /*  two chars are same, can start */
                    }                     /*  shifting at second position] */
                }
                last_dot = pp;    /* point at last dot so far... */
                *pp++ = '_';      /* convert dot to underscore for now */
                break;

            case ';':             /* start of VMS version? */
                lastsemi = pp;
                break;

            case ' ':                      /* change spaces to underscores */
                if (uO.sflag)              /*  only if requested */
                    *pp++ = '_';
                else
                    *pp++ = (char)workch;
                break;

            default:
                /* allow ASCII 255 and European characters in filenames: */
                if (isprint(workch) || workch >= 127)
                    *pp++ = (char)workch;

        } /* end switch */
    } /* end while loop */

    *pp = '\0';                   /* done with pathcomp:  terminate it */

    /* if not saving them, remove VMS version numbers (appended ";###") */
    if (!uO.V_flag && lastsemi) {
        pp = lastsemi;            /* semi-colon was omitted:  expect all #'s */
        while (isdigit((uch)(*pp)))
            ++pp;
        if (*pp == '\0')          /* only digits between ';' and end:  nuke */
            *lastsemi = '\0';
    }

    map2fat(pathcomp, last_dot);  /* 8.3 truncation (in place) */

/*---------------------------------------------------------------------------
    Report if directory was created (and no file to create:  filename ended
    in '/'), check name to be sure it exists, and combine path and name be-
    fore exiting.
  ---------------------------------------------------------------------------*/

    if (G.filename[strlen(G.filename) - 1] == '/') {
        checkdir(__G__ G.filename, GETPATH);
        if (created_dir) {
            if (QCOND2) {
                Info(slide, 0, ((char *)slide, LoadFarString(Creating),
                  FnFilter1(G.filename)));
            }
            return IZ_CREATED_DIR;   /* set dir time (note trailing '/') */
        }
        return 2;   /* dir existed already; don't look for data to extract */
    }

    if (*pathcomp == '\0') {
        Info(slide, 1, ((char *)slide, LoadFarString(ConversionFailed),
          FnFilter1(G.filename)));
        return 3;
    }

    checkdir(__G__ pathcomp, APPEND_NAME);  /* returns 1 if truncated: care? */
    checkdir(__G__ G.filename, GETPATH);

    return error;

} /* end function mapname() */



/**********************/
/* Function map2fat() */
/**********************/

static void map2fat(pathcomp, last_dot)
    char *pathcomp, *last_dot;
{
    char *pEnd = pathcomp + strlen(pathcomp);

/*---------------------------------------------------------------------------
    Case 1:  filename has no dot, so figure out if we should add one.  Note
    that the algorithm does not try to get too fancy:  if there are no dots
    already, the name either gets truncated at 8 characters or the last un-
    derscore is converted to a dot (only if more characters are saved that
    way).  In no case is a dot inserted between existing characters.

              GRR:  have problem if filename is volume label??

  ---------------------------------------------------------------------------*/

    /* pEnd = pathcomp + strlen(pathcomp); */
    if (last_dot == (char *)NULL) {   /* no dots:  check for underscores... */
        char *plu = strrchr(pathcomp, '_');   /* pointer to last underscore */

        if (plu == (char *)NULL) {  /* no dots, no underscores:  truncate at */
            if (pEnd > pathcomp+8)  /* 8 chars (could insert '.' and keep 11) */
                *(pEnd = pathcomp+8) = '\0';
        } else if (MIN(plu - pathcomp, 8) + MIN(pEnd - plu - 1, 3) > 8) {
            last_dot = plu;       /* be lazy:  drop through to next if-block */
        } else if ((pEnd - pathcomp) > 8)    /* more fits into just basename */
            pathcomp[8] = '\0';    /* than if convert last underscore to dot */
        /* else whole thing fits into 8 chars or less:  no change */
    }

/*---------------------------------------------------------------------------
    Case 2:  filename has dot in it, so truncate first half at 8 chars (shift
    extension if necessary) and second half at three.
  ---------------------------------------------------------------------------*/

    if (last_dot != (char *)NULL) {   /* one dot (or two, in the case of */
        *last_dot = '.';              /*  "..") is OK:  put it back in */

        if ((last_dot - pathcomp) > 8) {
            char *p=last_dot, *q=pathcomp+8;
            int i;

            for (i = 0;  (i < 4) && *p;  ++i)  /* too many chars in basename: */
                *q++ = *p++;                   /*  shift extension left and */
            *q = '\0';                         /*  truncate/terminate it */
        } else if ((pEnd - last_dot) > 4)
            last_dot[4] = '\0';                /* too many chars in extension */
        /* else filename is fine as is:  no change */
    }
} /* end function map2fat() */



/***********************/
/* Function checkdir() */
/***********************/

int checkdir(__G__ pathcomp, flag)
    __GDEF
    char *pathcomp;
    int flag;
/*
 * returns:  1 - (on APPEND_NAME) truncated filename
 *           2 - path doesn't exist, not allowed to create
 *           3 - path doesn't exist, tried to create and failed; or
 *               path exists and is not a directory, but is supposed to be
 *           4 - path is too long
 *          10 - can't allocate memory for filename buffers
 */
{
    static int rootlen = 0;   /* length of rootpath */
    static char *rootpath;    /* user's "extract-to" directory */
    static char *buildpath;   /* full path (so far) to extracted file */
    static char *end;         /* pointer to end of buildpath ('\0') */

#   define FN_MASK   7
#   define FUNCTION  (flag & FN_MASK)



/*---------------------------------------------------------------------------
    APPEND_DIR:  append the path component to the path being built and check
    for its existence.  If doesn't exist and we are creating directories, do
    so for this one; else signal success or error as appropriate.
  ---------------------------------------------------------------------------*/

    if (FUNCTION == APPEND_DIR) {
        int too_long = FALSE;

        Trace((stderr, "appending dir segment [%s]\n", pathcomp));
        while ((*end = *pathcomp++) != '\0')
            ++end;

        /* GRR:  could do better check, see if overrunning buffer as we go:
         * check end-buildpath after each append, set warning variable if
         * within 20 of FILNAMSIZ; then if var set, do careful check when
         * appending.  Clear variable when begin new path. */

        if ((end-buildpath) > FILNAMSIZ-3)  /* need '/', one-char name, '\0' */
            too_long = TRUE;                /* check if extracting directory? */
        if (stat(buildpath, &G.statbuf))    /* path doesn't exist */
        {
            if (!G.create_dirs) { /* told not to create (freshening) */
                free(buildpath);
                return 2;         /* path doesn't exist:  nothing to do */
            }
            if (too_long) {
                Info(slide, 1, ((char *)slide, LoadFarString(PathTooLong),
                  FnFilter1(buildpath)));
                free(buildpath);
                return 4;         /* no room for filenames:  fatal */
            }
            if (mkdir(buildpath, 0777) == -1) {   /* create the directory */
                Info(slide, 1, ((char *)slide, LoadFarString(CantCreateDir),
                  FnFilter2(buildpath), FnFilter1(G.filename)));
                free(buildpath);
                return 3;      /* path didn't exist, tried to create, failed */
            }
            created_dir = TRUE;
        } else if (!S_ISDIR(G.statbuf.st_mode)) {
            Info(slide, 1, ((char *)slide, LoadFarString(DirIsntDirectory),
              FnFilter2(buildpath), FnFilter1(G.filename)));
            free(buildpath);
            return 3;          /* path existed but wasn't dir */
        }
        if (too_long) {
            Info(slide, 1, ((char *)slide, LoadFarString(PathTooLong),
              FnFilter1(buildpath)));
            free(buildpath);
            return 4;         /* no room for filenames:  fatal */
        }
        *end++ = '/';
        *end = '\0';
        Trace((stderr, "buildpath now = [%s]\n", FnFilter1(buildpath)));
        return 0;

    } /* end if (FUNCTION == APPEND_DIR) */

/*---------------------------------------------------------------------------
    GETPATH:  copy full path to the string pointed at by pathcomp, and free
    buildpath.
  ---------------------------------------------------------------------------*/

    if (FUNCTION == GETPATH) {
        strcpy(pathcomp, buildpath);
        Trace((stderr, "getting and freeing path [%s]\n",
          FnFilter1(pathcomp)));
        free(buildpath);
        buildpath = end = (char *)NULL;
        return 0;
    }

/*---------------------------------------------------------------------------
    APPEND_NAME:  assume the path component is the filename; append it and
    return without checking for existence.
  ---------------------------------------------------------------------------*/

    if (FUNCTION == APPEND_NAME) {
        Trace((stderr, "appending filename [%s]\n", FnFilter1(pathcomp)));
        while ((*end = *pathcomp++) != '\0') {
            ++end;
            if ((end-buildpath) >= FILNAMSIZ) {
                *--end = '\0';