atari.c

压缩算法的源代码

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

  atari.c

  Atari-specific routines for use with Info-ZIP's UnZip 5.1 and later.

  Contains:  readdir()
             do_wild()           <-- generic enough to put in file_io.c?
             mapattr()
             mapname()
             checkdir()
             mkdir()
             close_outfile()
             version()

  Due to the amazing MiNT library being very, very close to BSD unix's
  library, I'm using the unix.c as a base for this.  Note:  If you're not
  going to compile this with the MiNT libraries (for GNU C, Turbo C, Pure C,
  Lattice C, or Heat & Serve C), you're going to be in for some nasty work.
  Most of the modifications in this file were made by Chris Herborth
  ([e-mail]) and /should/ be marked with [cjh].

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


#include "unzip.h"
#include <dirent.h>            /* MiNTlibs has dirent [cjh] */

static int created_dir;        /* used in mapname(), checkdir() */
static int renamed_fullpath;   /* ditto */

/**********************/
/* Function do_wild() */   /* for porting:  dir separator; match(ignore_case) */
/**********************/

char *do_wild(wildspec)
    char *wildspec;         /* only used first time on a given dir */
{
    static DIR *dir = NULL;
    static char *dirname, *wildname, matchname[FILNAMSIZ];
    static int firstcall=TRUE, have_dirname, dirnamelen;
    struct dirent *file;


    /* Even when we're just returning wildspec, we *always* do so in
     * matchname[]--calling routine is allowed to append four characters
     * to the returned string, and wildspec may be a pointer to argv[].
     */
    if (firstcall) {        /* first call:  must initialize everything */
        firstcall = FALSE;

        /* break the wildspec into a directory part and a wildcard filename */
        if ((wildname = strrchr(wildspec, '/')) == NULL) {
            dirname = ".";
            dirnamelen = 1;
            have_dirname = FALSE;
            wildname = wildspec;
        } else {
            ++wildname;     /* point at character after '/' */
            dirnamelen = wildname - wildspec;
            if ((dirname = (char *)malloc(dirnamelen+1)) == NULL) {
                fprintf(stderr, "warning:  can't allocate wildcard buffers\n");
                strcpy(matchname, wildspec);
                return matchname;   /* but maybe filespec was not a wildcard */
            }
            strncpy(dirname, wildspec, dirnamelen);
            dirname[dirnamelen] = '\0';   /* terminate for strcpy below */
            have_dirname = TRUE;
        }

        if ((dir = opendir(dirname)) != NULL) {
            while ((file = readdir(dir)) != NULL) {
                if (file->d_name[0] == '.' && wildname[0] != '.')
                    continue;  /* Unix:  '*' and '?' do not match leading dot */
                    /* Need something here for TOS filesystem? [cjh] */
                if (match(file->d_name, wildname, 0)) {  /* 0 == case sens. */
                    if (have_dirname) {
                        strcpy(matchname, dirname);
                        strcpy(matchname+dirnamelen, file->d_name);
                    } else
                        strcpy(matchname, file->d_name);
                    return matchname;
                }
            }
            /* if we get to here directory is exhausted, so close it */
            closedir(dir);
            dir = NULL;
        }

        /* return the raw wildspec in case that works (e.g., directory not
         * searchable, but filespec was not wild and file is readable) */
        strcpy(matchname, wildspec);
        return matchname;
    }

    /* last time through, might have failed opendir but returned raw wildspec */
    if (dir == NULL) {
        firstcall = TRUE;  /* nothing left to try--reset for new wildspec */
        if (have_dirname)
            free(dirname);
        return (char *)NULL;
    }

    /* If we've gotten this far, we've read and matched at least one entry
     * successfully (in a previous call), so dirname has been copied into
     * matchname already.
     */
    while ((file = readdir(dir)) != NULL)
        /* May need special TOS handling here. [cjh] */
        if (match(file->d_name, wildname, 0)) {   /* 0 == don't ignore case */
            if (have_dirname) {
                /* strcpy(matchname, dirname); */
                strcpy(matchname+dirnamelen, file->d_name);
            } else
                strcpy(matchname, file->d_name);
            return matchname;
        }

    closedir(dir);     /* have read at least one dir entry; nothing left */
    dir = NULL;
    firstcall = TRUE;  /* reset for new wildspec */
    if (have_dirname)
        free(dirname);
    return (char *)NULL;

} /* end function do_wild() */





/**********************/
/* Function mapattr() */
/**********************/

int mapattr()
{
    ulg tmp = crec.external_file_attributes;

    switch (pInfo->hostnum) {
        case UNIX_:
            /* minix filesystem under MiNT on Atari [cjh] */
        case VMS_:
            pInfo->file_attr = (unsigned)(tmp >> 16);
            return 0;
        case AMIGA_:
            tmp = (unsigned)(tmp>>17 & 7);   /* Amiga RWE bits */
            pInfo->file_attr = (unsigned)(tmp<<6 | tmp<<3 | tmp);
            break;
        /* all remaining cases:  expand MSDOS read-only bit into write perms */
        case FS_FAT_:
        case FS_HPFS_:
        case FS_NTFS_:
        case MAC_:
        case ATARI_:             /* (used to set = 0666) */
            /* TOS filesystem [cjh] */
        case TOPS20_:
        default:
            tmp = !(tmp & 1) << 1;   /* read-only bit --> write perms bits */
            pInfo->file_attr = (unsigned)(0444 | tmp<<6 | tmp<<3 | tmp);
            break;
    } /* end switch (host-OS-created-by) */

    /* for originating systems with no concept of "group," "other," "system": */
    umask( (int)(tmp=umask(0)) );    /* apply mask to expanded r/w(/x) perms */
    pInfo->file_attr &= ~tmp;

    return 0;

} /* end function mapattr() */





/************************/
/*  Function mapname()  */
/************************/

int mapname(renamed)  /* return 0 if no error, 1 if caution (filename trunc), */
    int renamed;      /* 2 if warning (skip file because dir doesn't exist), */
{                     /* 3 if error (skip file), 10 if no memory (skip file) */
    char pathcomp[FILNAMSIZ];   /* path-component buffer */
    char *pp, *cp=NULL;         /* character pointers */
    char *lastsemi = NULL;      /* pointer to last semi-colon in pathcomp */
    int quote = FALSE;          /* flags */
    int error = 0;
    register unsigned workch;   /* hold the character being tested */


/*---------------------------------------------------------------------------
    Initialize various pointers and counters and stuff.
  ---------------------------------------------------------------------------*/

    if (pInfo->vollabel)
        return IZ_VOL_LABEL;    /* can't set disk volume labels in Unix */

    /* can create path as long as not just freshening, or if user told us */
    create_dirs = (!fflag || renamed);

    created_dir = FALSE;        /* not yet */

    /* user gave full pathname:  don't prepend rootpath */
    renamed_fullpath = (renamed && (*filename == '/'));

    if (checkdir((char *)NULL, INIT) == 10)
        return 10;              /* initialize path buffer, unless no memory */

    *pathcomp = '\0';           /* initialize translation buffer */
    pp = pathcomp;              /* point to translation buffer */
    if (jflag)                  /* junking directories */
        cp = (char *)strrchr(filename, '/');
    if (cp == NULL)             /* no '/' or not junking dirs */
        cp = filename;          /* point to internal zipfile-member pathname */
    else
        ++cp;                   /* point to start of last component of path */

/*---------------------------------------------------------------------------
    Begin main loop through characters in filename.
  ---------------------------------------------------------------------------*/

    while ((workch = (uch)*cp++) != 0) {

        if (quote) {                 /* if character quoted, */
            *pp++ = (char)workch;    /*  include it literally */
            quote = FALSE;
        } else
            switch (workch) {
            case '/':             /* can assume -j flag not given */
                *pp = '\0';
                if ((error = checkdir(pathcomp, APPEND_DIR)) > 1)
                    return error;
                pp = pathcomp;    /* reset conversion buffer for next piece */
                lastsemi = NULL;  /* leave directory semi-colons alone */
                break;

            case ';':             /* VMS version (or DEC-20 attrib?) */
                lastsemi = pp;         /* keep for now; remove VMS ";##" */
                *pp++ = (char)workch;  /*  later, if requested */
                break;

            case '\026':          /* control-V quote for special chars */
                quote = TRUE;     /* set flag for next character */
                break;

#ifdef MTS
            case ' ':             /* change spaces to underscore under */
                *pp++ = '_';      /*  MTS; leave as spaces under Unix */
                break;
#endif

            default:
                /* allow European characters in filenames: */
                if (isprint(workch) || (128 <= workch && workch <= 254))
                    *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 (!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;
/* SHORT_NAMES required for TOS, but it has to co-exist for minix fs... [cjh] */
#ifdef SHORT_NAMES
        char *old_end = end;
#endif