amiga.c

压缩算法的源代码

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

  amiga.c

  Amiga-specific routines for use with Info-ZIP's UnZip 5.1 and later.
  See History.5xx for revision history.

  Contents:   mapattr()
              mapname()
              do_wild()
              checkdir()
              cmptime()
              invlocal()
              close_outfile()
              _abort()         (Aztec C only)
              version()

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


#include "unzip.h"

/* Globular varibundus */

static int created_dir;      /* used in mapname(), checkdir() */
static int renamed_fullpath; /* ditto */
#define PERMS   0777
#define MKDIR(path,mode) mkdir(path)


#ifndef S_ISCRIPT          /* not having one implies you have none */
#  define S_IARCHIVE 0020  /* not modified since this bit was last set */
#  define S_IREAD    0010  /* can be opened for reading */
#  define S_IWRITE   0004  /* can be opened for writing */
#  define S_IDELETE  0001  /* can be deleted */
#endif /* S_ISCRIPT */

#ifndef S_IRWD
#  define S_IRWD     0015  /* useful combo of Amiga privileges */
#endif /* !S_IRWD */

#ifndef S_IHIDDEN
#  define S_IHIDDEN  0200  /* hidden supported in future AmigaDOS (someday) */
#endif /* !S_HIDDEN */



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

int mapattr(void)      /* Amiga version */
{
    ulg  tmp = crec.external_file_attributes;


    /* Amiga attributes = hsparwed = hidden, script, pure, archive,
     * read, write, execute, delete */

    switch (pInfo->hostnum) {
        case AMIGA_:
            if ((tmp & 1) == (tmp>>18 & 1))
                tmp ^= 0x000F0000;      /* PKAZip compatibility kluge */
            /* turn off archive bit for restored Amiga files */
            pInfo->file_attr = (unsigned)((tmp>>16) & (~S_IARCHIVE));
            break;

        case UNIX_:   /* preserve read, write, execute:  use logical-OR of */
        case VMS_:    /* user, group, and other; if writable, set delete bit */
            tmp >>= 16;
            tmp = (( tmp>>6 | tmp>>3 | tmp) & 07) << 1;
            pInfo->file_attr = (unsigned)(tmp&S_IWRITE? tmp|S_IDELETE : tmp);
            break;

        /* all other platforms:  assume read-only bit in DOS half of attribute
         * word is set correctly ==> will become READ or READ+WRITE+DELETE */
        case FS_FAT_:
        case FS_HPFS_:  /* can add S_IHIDDEN check to MSDOS/OS2/NT eventually */
        case FS_NTFS_:
        case MAC_:
        case ATARI_:
        case TOPS20_:
        default:
            pInfo->file_attr = (unsigned)(tmp&1? S_IREAD : S_IRWD); 
            break;

    } /* end switch (host-OS-created-by) */

    pInfo->file_attr &= 0xff;   /* mask off all but lower eight bits */
    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.
  ---------------------------------------------------------------------------*/

    /* 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 && strchr(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;

            default:
                /* allow European characters in filenames: */
                if (isprint(workch) || (128 <= workch && workch <= 255))
                    *pp++ = (char)workch;
            } /* end switch */

    } /* end while loop */

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

    /* if not saving them, remove with 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] == '/') {
        if (checkdir(filename, GETPATH) == 1) {
            fprintf(stderr, "pathname too long:  truncat{ed/ing}\n");
            return 1;  /* GRR:  NEEDS WORK! (do checking only when appending) */
        }
        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;
    }

    if ((error = checkdir(pathcomp, APPEND_NAME)) == 1) {
        /* GRR:  OK if truncated here:  warn and continue */
        /* (warn in checkdir?) */
    }
    checkdir(filename, GETPATH);

    return error;

} /* end function mapname() */


static int ispattern(char *p)
{
    register char c;
    while (c = *p++)
	if (c == '\\') {
	    if (!*++p)
		return FALSE;
        } else if (c == '?' || c == '*')
            return TRUE;
        else if (c == '[') {
            for (;;) {
                if (!(c = *p++))
                    return FALSE;
                else if (c == '\\') {
                    if (!*++p)
			return FALSE;
                } else if (c == ']')
                    return TRUE;
            }
        }
    return FALSE;
}

/**********************/
/* 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;
    BPTR lok = 0;
    /* 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;
        /* avoid needless readdir() scans: */
        if (!ispattern(wildspec) || (lok = Lock(wildspec, ACCESS_READ))) {
            if (lok) UnLock(lok);
            have_dirname = FALSE;
            strcpy(matchname, wildspec);
            return matchname;
        }

        /* break the wildspec into a directory part and a wildcard filename */
        if ((wildname = strrchr(wildspec, '/')) == NULL
                        && (wildname = strrchr(wildspec, ':')) == NULL) {
            dirname = "";               /* current dir */
            dirnamelen = 1;
            have_dirname = FALSE;
            wildname = wildspec;
        } else {
            ++wildname;     /* point at character after '/' or ':' */
            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;
            have_dirname = TRUE;
        }

        if ((dir = opendir(dirname)) != NULL) {
            while ((file = readdir(dir)) != NULL) {
                if (match(file->d_name, wildname, 1)) {  /* case insensitive */
                    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)
        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 checkdir() */
/***********************/

int checkdir(pathcomp, flag)
    char *pathcomp;
    int flag;
/*
 * returns:  1 - (on APPEND_xxx) truncated path component
 *           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
 *          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.
  ---------------------------------------------------------------------------*/

/* GRR:  check path length after each segment:  warn about truncation */

    if (FUNCTION == APPEND_DIR) {
        Trace((stderr, "appending dir segment [%s]\n", pathcomp));
        while ((*end = *pathcomp++))
            ++end;
        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 (MKDIR(buildpath, 0777) == -1) {   /* create the directory */
                fprintf(stderr, 
                "checkdir:  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 */