unix.c

压缩算法的源代码

    } /* end while loop */

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

    /* if not saving them, remove VMS version numbers (appended ";###") */
    if (!V_flag && lastsemi) {
        pp = lastsemi + 1;
        while (isdigit((uch)(*pp)))
            ++pp;
        if (*pp == '\0')          /* only digits between ';' and end:  nuke */
            *lastsemi = '\0';
    }

/*---------------------------------------------------------------------------
    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 (filename[strlen(filename) - 1] == '/') {
        checkdir(filename, GETPATH);
        if (created_dir && QCOND2) {
            FPRINTF(stdout, "   creating: %s\n", 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') {
        FPRINTF(stderr, "mapname:  conversion of %s failed\n", filename);
        return 3;
    }

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

    return error;

} /* end function mapname() */




#if 0  /*========== NOTES ==========*/

  extract-to dir:      a:path/
  buildpath:           path1/path2/ ...   (NULL-terminated)
  pathcomp:                filename 

  mapname():
    loop over chars in zipfile member name
      checkdir(path component, COMPONENT | CREATEDIR) --> map as required?
        (d:/tmp/unzip/)                    (disk:[tmp.unzip.)
        (d:/tmp/unzip/jj/)                 (disk:[tmp.unzip.jj.)
        (d:/tmp/unzip/jj/temp/)            (disk:[tmp.unzip.jj.temp.)
    finally add filename itself and check for existence? (could use with rename)
        (d:/tmp/unzip/jj/temp/msg.outdir)  (disk:[tmp.unzip.jj.temp]msg.outdir)
    checkdir(name, COPYFREE)     -->  copy path to name and free space

#endif /* 0 */




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

int checkdir(pathcomp, flag)
    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;
#ifdef SHORT_NAMES
        char *old_end = end;
#endif

        Trace((stderr, "appending dir segment [%s]\n", pathcomp));
        while ((*end = *pathcomp++) != '\0')
            ++end;
#ifdef SHORT_NAMES   /* path components restricted to 14 chars, typically */
        if ((end-old_end) > FILENAME_MAX)  /* GRR:  proper constant? */
            *(end = old_end + FILENAME_MAX) = '\0';
#endif

        /* 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, &statbuf)) {    /* path doesn't exist */
            if (!create_dirs) {   /* told not to create (freshening) */
                free(buildpath);
                return 2;         /* path doesn't exist:  nothing to do */
            }
            if (too_long) {
                FPRINTF(stderr, "checkdir error:  path too long: %s\n",
                  buildpath);
                fflush(stderr);
                free(buildpath);
                return 4;         /* no room for filenames:  fatal */
            }
            if (mkdir(buildpath, 0777) == -1) {   /* create the directory */
                FPRINTF(stderr, "checkdir error:  can't create %s\n\
                 unable to process %s.\n", buildpath, filename);
                fflush(stderr);
                free(buildpath);
                return 3;      /* path didn't exist, tried to create, failed */
            }
            created_dir = TRUE;
        } else if (!S_ISDIR(statbuf.st_mode)) {
            FPRINTF(stderr, "checkdir error:  %s exists but is not directory\n\
                 unable to process %s.\n", buildpath, filename);
            fflush(stderr);
            free(buildpath);
            return 3;          /* path existed but wasn't dir */
        }
        if (too_long) {
            FPRINTF(stderr, "checkdir error:  path too long: %s\n", buildpath);
            fflush(stderr);
            free(buildpath);
            return 4;         /* no room for filenames:  fatal */
        }
        *end++ = '/';
        *end = '\0';
        Trace((stderr, "buildpath now = [%s]\n", 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", 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) {
#ifdef SHORT_NAMES
        char *old_end = end;
#endif

        Trace((stderr, "appending filename [%s]\n", pathcomp));
        while ((*end = *pathcomp++) != '\0') {
            ++end;
#ifdef SHORT_NAMES  /* truncate name at 14 characters, typically */
            if ((end-old_end) > FILENAME_MAX)      /* GRR:  proper constant? */
                *(end = old_end + FILENAME_MAX) = '\0';
#endif
            if ((end-buildpath) >= FILNAMSIZ) {
                *--end = '\0';
                FPRINTF(stderr, "checkdir warning:  path too long; truncating\n\
checkdir warning:  path too long; truncating\n\
                   %s\n                -> %s\n", filename, buildpath);
                fflush(stderr);
                return 1;   /* filename truncated */
            }
        }
        Trace((stderr, "buildpath now = [%s]\n", buildpath));
        return 0;  /* could check for existence here, prompt for new name... */
    }

/*---------------------------------------------------------------------------
    INIT:  allocate and initialize buffer space for the file currently being
    extracted.  If file was renamed with an absolute path, don't prepend the
    extract-to path.
  ---------------------------------------------------------------------------*/

/* GRR:  for VMS and TOPS-20, add up to 13 to strlen */

    if (FUNCTION == INIT) {
        Trace((stderr, "initializing buildpath to "));
        if ((buildpath = (char *)malloc(strlen(filename)+rootlen+1)) ==
            (char *)NULL)
            return 10;
        if ((rootlen > 0) && !renamed_fullpath) {
            strcpy(buildpath, rootpath);
            end = buildpath + rootlen;
        } else {
            *buildpath = '\0';
            end = buildpath;
        }
        Trace((stderr, "[%s]\n", buildpath));
        return 0;
    }

/*---------------------------------------------------------------------------
    ROOT:  if appropriate, store the path in rootpath and create it if neces-
    sary; else assume it's a zipfile member and return.  This path segment
    gets used in extracting all members from every zipfile specified on the
    command line.
  ---------------------------------------------------------------------------*/

#if (!defined(SFX) || defined(SFX_EXDIR))
    if (FUNCTION == ROOT) {
        Trace((stderr, "initializing root path to [%s]\n", pathcomp));
        if (pathcomp == (char *)NULL) {
            rootlen = 0;
            return 0;
        }
        if ((rootlen = strlen(pathcomp)) > 0) {
            int had_trailing_pathsep=FALSE;

            if (pathcomp[rootlen-1] == '/') {
                pathcomp[--rootlen] = '\0';
                had_trailing_pathsep = TRUE;
            }
            if (rootlen > 0 && (stat(pathcomp, &statbuf) ||
                !S_ISDIR(statbuf.st_mode)))          /* path does not exist */
            {
                if (!create_dirs                     /* || iswild(pathcomp) */
#ifdef OLD_EXDIR
                                 || !had_trailing_pathsep
#endif
                                                         ) {
                    rootlen = 0;
                    return 2;   /* skip (or treat as stored file) */
                }
                /* create the directory (could add loop here to scan pathcomp
                 * and create more than one level, but why really necessary?) */
                if (mkdir(pathcomp, 0777) == -1) {
                    FPRINTF(stderr,
                      "checkdir:  can't create extraction directory: %s\n",
                      pathcomp);
                    fflush(stderr);
                    rootlen = 0;   /* path didn't exist, tried to create, and */
                    return 3;  /* failed:  file exists, or 2+ levels required */
                }
            }
            if ((rootpath = (char *)malloc(rootlen+2)) == (char *)NULL) {
                rootlen = 0;
                return 10;
            }
            strcpy(rootpath, pathcomp);
            rootpath[rootlen++] = '/';
            rootpath[rootlen] = '\0';
        }
        Trace((stderr, "rootpath now = [%s]\n", rootpath));
        return 0;
    }
#endif /* !SFX || SFX_EXDIR */

/*---------------------------------------------------------------------------
    END:  free rootpath, immediately prior to program exit.
  ---------------------------------------------------------------------------*/

    if (FUNCTION == END) {
        Trace((stderr, "freeing rootpath\n"));
        if (rootlen > 0)
            free(rootpath);
        return 0;
    }

    return 99;  /* should never reach */

} /* end function checkdir() */





#ifdef NO_MKDIR

/********************/
/* Function mkdir() */
/********************/

int mkdir(path, mode)
    char *path;
    int mode;   /* ignored */
/*
 * returns:   0 - successful
 *           -1 - failed (errno not set, however)
 */
{
    char command[FILNAMSIZ+40]; /* buffer for system() call */

    /* GRR 930416:  added single quotes around path to avoid bug with
     * creating directories with ampersands in name; not yet tested */
    sprintf(command, "IFS=\" \t\n\" /bin/mkdir '%s' 2>/dev/null", path);
    if (system(command))
        return -1;
    return 0;
}

#endif /* NO_MKDIR */