ckufio.c

C-Kermit源码。是使用串口/Modem和网络通讯的程序

#ifdef IKSD
    if (inserver && !local && (n == ZCTERM || n == ZSTDIO)) {
#ifdef COMMENT
        return(ttoc(LF));
#else
        return(0);                      /* See comments in zsout() */
#endif /* COMMENT */
    }
#endif /* IKSD */

    if (n == ZSFILE)                    /* Session log is unbuffered */
      return(write(fileno(fp[n]),"\n",1));
    else if (fputs("\n",fp[n]) == EOF)
      return(-1);
    if (n == ZDIFIL || n == ZWFILE)     /* Flush connection log records */
      fflush(fp[n]);
    return(0);
}

/*  Z S O U T X  --  Write x characters to file, unbuffered.  */

int
zsoutx(n,s,x) int n, x; char *s; {
#ifdef IKSD
    if (inserver && !local && (n == ZCTERM || n == ZSTDIO)) {
#ifdef COMMENT
        return(ttol(s,x));              /* See comments in zsout() */
#else
        return(x);
#endif /* COMMENT */
    }
#endif /* IKSD */

#ifdef COMMENT
    if (chkfn(n) < 1) return(-1);
    return(write(fp[n]->_file,s,x));
#endif /* COMMENT */
    return(write(fileno(fp[n]),s,x) == x ? x : -1);
}

/*  Z C H O U T  --  Add a character to the given file.  */

/*  Should return 0 or greater on success, -1 on failure (e.g. disk full)  */

int
#ifdef CK_ANSIC
zchout(register int n, char c)
#else
zchout(n,c) register int n; char c;
#endif /* CK_ANSIC */
/* zchout() */ {
    /* if (chkfn(n) < 1) return(-1); */

#ifdef IKSD
    if (inserver && !local && (n == ZCTERM || n == ZSTDIO)) {
#ifdef COMMENT
        return(ttoc(c));
#else
        return(0);                      /* See comments in zsout() */
#endif /* COMMENT */
    }
#endif /* IKSD */

    if (n == ZSFILE)                    /* Use unbuffered for session log */
      return(write(fileno(fp[n]),&c,1) == 1 ? 0 : -1);
                                /* Buffered for everything else */
    if (putc(c,fp[n]) == EOF)   /* If true, maybe there was an error */
      return(ferror(fp[n])?-1:0);       /* Check to make sure */
    else                                /* Otherwise... */
      return(0);                        /* There was no error. */
}

/* (PWP) buffered character output routine to speed up file IO */

int
zoutdump() {
    int x;
    char * zp;
    zoutptr = zoutbuffer;               /* Reset buffer pointer in all cases */
#ifdef DEBUG
    if (deblog)
      debug(F101,"zoutdump zoutcnt","",zoutcnt);
#endif /* DEBUG */
    if (zoutcnt == 0) {                 /* Nothing to output */
        return(0);
    } else if (zoutcnt < 0) {           /* Unexpected negative argument */
        zoutcnt = 0;                    /* Reset output buffer count */
        return(-1);                     /* and fail. */
    }

#ifdef IKSD
    if (inserver && !local && fp[ZOFILE] == stdout) {
#ifdef COMMENT
        x = ttol(zoutbuffer,zoutcnt);
#else
        x = 1;                          /* See comments in zsout() */
#endif /* COMMENT */
        zoutcnt = 0;
        return(x > 0 ? 0 : -1);
    }
#endif /* IKSD */

/*
  Frank Prindle suggested that replacing this fwrite() by an fflush()
  followed by a write() would improve the efficiency, especially when
  writing to stdout.  Subsequent tests showed a 5-fold improvement.
*/
#ifdef COMMENT
    if (x = fwrite(zoutbuffer, 1, zoutcnt, fp[ZOFILE])) ...
#endif /* COMMENT */

#ifndef CK_NONBLOCK
    fflush(fp[ZOFILE]);
#endif /* CK_NONBLOCK */
    zp = zoutbuffer;
    while (zoutcnt > 0) {
        if ((x = write(fileno(fp[ZOFILE]),zp,zoutcnt)) > -1) {
#ifdef DEBUG
            if (deblog)                 /* Save a function call... */
              debug(F101,"zoutdump wrote","",x);
#endif /* DEBUG */
            zoutcnt -= x;               /* Adjust output buffer count */
            zp += x;                    /* and pointer */
        } else {
#ifdef DEBUG
            if (deblog) {
                debug(F101,"zoutdump write error","",errno);
                debug(F101,"zoutdump write returns","",x);
            }
#endif /* DEBUG */
            zoutcnt = 0;                /* Reset output buffer count */
            return(-1);                 /* write() failed */
        }
    }
    return(0);
}

/*  C H K F N  --  Internal function to verify file number is ok  */

/*
 Returns:
  -1: File number n is out of range
   0: n is in range, but file is not open
   1: n in range and file is open
*/
int
chkfn(n) int n; {
    /* if (n != ZDFILE) debug(F101,"chkfn","",n); */
    if (n < 0 || n >= ZNFILS) {
        if (n != ZDFILE) debug(F101,"chkfn out of range","",n);
        return(-1);
    } else {
        /* if (n != ZDFILE) debug(F101,"chkfn fp[n]","",fp[n]); */
        return((fp[n] == NULL) ? 0 : 1);
    }
}

/*  Z G E T F S -- Return file size regardless of accessibility */
/*
  Used for directory listings, etc.
  Returns:
    The size of the file in bytes, 0 or greater, if the size can be learned.
    -1 if the file size can not be obtained.
  Also (and this is a hack just for UNIX):
    If the argument is the name of a symbolic link,
    the global variable issymlink is set to 1,
    and the global buffer linkname[] gets the link value.
    And it sets zgfs_dir to 1 if it's a directory, otherwise 0.
  This lets us avoid numerous redundant calls to stat().
*/
int zgfs_link = 0;
int zgfs_dir = 0;
time_t zgfs_mtime = 0;
unsigned int zgfs_mode = 0;

#ifdef CKSYMLINK
char linkname[CKMAXPATH+1];
#ifndef _IFLNK
#define _IFLNK 0120000
#endif /* _IFLNK */
#endif /* CKSYMLINK */

long
zgetfs(name) char *name; {
    struct stat buf;
    char fnam[CKMAXPATH+4];
    long size = -1L;
    int x;
    int needrlink = 0;
    char * s;

#ifdef UNIX
    x = strlen(name);
    if (x == 9 && !strcmp(name,"/dev/null"))
      return(0);
#endif /* UNIX */

    s = name;
#ifdef DTILDE
    if (*s == '~') {
        s = tilde_expand(s);
        if (!s) s = "";
        if (!*s) s = name;
    }
#endif /* DTILDE */
    x = ckstrncpy(fnam,s,CKMAXPATH);
    s = fnam;
    if (x > 0 && s[x-1] == '/')
      s[x-1] = '\0';

    zgfs_dir = 0;                       /* Assume it's not a directory */
    zgfs_link = 0;                      /* Assume it's not a symlink */
    zgfs_mtime = 0;			/* No time yet */
    zgfs_mode = 0;			/* No permission bits yet */

#ifdef CKSYMLINK                        /* We're doing symlinks? */
#ifdef USE_LSTAT                        /* OK to use lstat()? */
    x = lstat(s,&buf);
    debug(F101,"STAT","",1);
    if (x < 0)                          /* stat() failed */
      return(-1);
    if (                                /* Now see if it's a symlink */
#ifdef S_ISLNK
        S_ISLNK(buf.st_mode)
#else
#ifdef _IFLNK
        ((_IFMT & buf.st_mode) == _IFLNK)
#endif /* _IFLNK */
#endif /* S_ISLNK */
        ) {
        zgfs_link = 1;                  /* It's a symlink */
        linkname[0] = '\0';             /* Get the name */
        x = readlink(s,linkname,CKMAXPATH);
        debug(F101,"zgetfs readlink",s,x);
        if (x > -1 && x < CKMAXPATH) {  /* It's a link */
            linkname[x] = '\0';
            size = buf.st_size;         /* Remember size of link */
            x = stat(s,&buf);           /* Now stat the linked-to file */
	    debug(F101,"STAT","",2);
            if (x < 0)                  /* so we can see if it's a directory */
              return(-1);
        } else {
            strcpy(linkname,"(lookup failed)");
        }
    }
#else  /* !USE_LSTAT */
    x = stat(s,&buf);                   /* No lstat(), use stat() instead */
    debug(F101,"STAT","",3);
    if (x < 0)
      return(-1);
#endif /* USE_STAT */

    /* Do we need to call readlink()? */

#ifdef NOLINKBITS
/*
  lstat() does not work in SCO operating systems.  From "man NS lstat":

  lstat obtains information about the file named by path. In the case of a
  symbolic link, lstat returns information about the link, and not the file
  named by the link. It is only used by the NFS automount daemon and should
  not be utilized by users.
*/
    needrlink = 1;
    debug(F101,"zgetfs forced needrlink","",needrlink);
#else
#ifdef S_ISLNK
    needrlink = S_ISLNK(buf.st_mode);
    debug(F101,"zgetfs S_ISLNK needrlink","",needrlink);
#else
#ifdef _IFLNK
    needrlink = (_IFMT & buf.st_mode) == _IFLNK;
    debug(F101,"zgetfs _IFLNK needrlink","",needrlink);
#else
    needrlink = 1;
    debug(F101,"zgetfs default needrlink","",needrlink);
#endif /* _IFLNK */
#endif /* S_ISLNK */
#endif /* NOLINKBITS */

    if (needrlink) {
        linkname[0] = '\0';
        errno = 0;
        x = readlink(s,linkname,CKMAXPATH);
#ifdef DEBUG
        debug(F111,"zgetfs readlink",s,x);
        if (x < 0)
          debug(F101,"zgetfs readlink errno","",errno);
        else
          debug(F110,"zgetfs readlink result",linkname,0);
#endif /* DEBUG */
        if (x > -1 && x < CKMAXPATH) {
            zgfs_link = 1;
            linkname[x] = '\0';
        }
    }
#else  /* !CKSYMLINK */
    x = stat(s,&buf);                   /* Just stat the file */
    debug(F101,"STAT","",4);
    if (x < 0)                          /* and get the size */
      return(-1);
#endif /* CKSYMLINK */

    zgfs_mtime = buf.st_mtime;
    zgfs_mode = buf.st_mode;
    zgfs_dir = (S_ISDIR(buf.st_mode)) ? 1 : 0; /* Set "is directory" flag */
    return((size < 0L) ? buf.st_size : size); /* Return the size */
}


/*  Z C H K I  --  Check if input file exists and is readable  */

/*
  Returns:
   >= 0 if the file can be read (returns the size).
     -1 if file doesn't exist or can't be accessed,
     -2 if file exists but is not readable (e.g. a directory file).
     -3 if file exists but protected against read access.

  For Berkeley Unix, a file must be of type "regular" to be readable.
  Directory files, special files, and symbolic links are not readable.
*/
long
zchki(name) char *name; {
    struct stat buf;
    char * s;
    int x, itsadir = 0;
    extern int zchkid;

    if (!name)
      return(-1);
    x = strlen(name);
    if (x < 1)
      return(-1);
    s = name;

#ifdef UNIX
    if (x == 9 && !strcmp(s,"/dev/null"))
      return(0);
#endif /* UNIX */

#ifdef DTILDE
    if (*s == '~') {
        s = tilde_expand(s);
        if (!s) s = "";
        if (!*s) s = name;
    }
#endif /* DTILDE */

    x = stat(s,&buf);
    debug(F101,"STAT","",5);
    if (x < 0) {
        debug(F111,"zchki stat fails",s,errno);
        return(-1);
    }
    if (S_ISDIR (buf.st_mode))
      itsadir = 1;

    if (!(itsadir && zchkid)) {         /* Unless this... */
        if (!S_ISREG (buf.st_mode)      /* Must be regular file */
#ifdef S_ISFIFO
            && !S_ISFIFO (buf.st_mode)  /* or FIFO */
#endif /* S_ISFIFO */
            ) {
            debug(F111,"zchki not regular file",s,x);
            return(-2);
        }
    }
    debug(F111,"zchki stat ok:",s,x);

#ifdef SW_ACC_ID
    debug(F100,"zchki swapping ids for access()","",0);
    priv_on();
#endif /* SW_ACC_ID */
    x = access(s,R_OK);
#ifdef SW_ACC_ID
    priv_off();
    debug(F100,"zchki swapped ids restored","",0);
#endif /* SW_ACC_ID */
    if (x < 0) {                        /* Is the file accessible? */
        debug(F111,"zchki access failed:",s,x); /* No */
        return(-3);
    } else {
        iflen = buf.st_size;            /* Yes, remember size */
        ckstrncpy(nambuf,s,CKMAXPATH);  /* and name globally. */
        debug(F111,"zchki access ok:",s,iflen);
        return((iflen > -1L) ? iflen : 0L);
    }
}

/*  Z C H K O  --  Check if output file can be created  */

/*
  Returns -1 if write permission for the file would be denied, 0 otherwise.

  NOTE: The design is flawed.  There is no distinction among:
   . Can I overwrite an existing file?
   . Can I create a file (or directory) in an existing directory?
   . Can I create a file (or directory) and its parent(s)?
*/
int
zchko(name) char *name; {
    int i, x, itsadir = 0;
    char *s;
    extern int zchkod;                  /* Used by IF WRITEABLE */

    if (!name) return(-1);              /* Watch out for null pointer. */
    x = (int)strlen(name);              /* Get length of filename */
    debug(F111,"zchko",name,zchkod);

#ifdef UNIX
/*
  Writing to null device is OK.
*/
    if (x == 9 && !strcmp(name,"/dev/null"))
      return(0);
#endif /* UNIX */

    s = name;
#ifdef DTILDE
    if (*s == '~') {
        s = tilde_expand(s);
        if (!s) s = "";
        if (!*s) s = name;
    }
#endif /* DTILDE */
    name = s;
    s = NULL;
/*
  zchkod is a global flag meaning we're checking not to see if the directory
  file is writeable, but if it's OK to create files IN the directory.
*/
    if (!zchkod && isdir(name))         /* Directories are not writeable */
      return(-1);

    s = malloc(x+3);                    /* Must copy because we can't */
    if (!s) {                           /* write into our argument. */
        fprintf(stderr,"zchko: Malloc error 46\n");
        return(-1);
    }
    strcpy(s,name);

    for (i = x; i > 0; i--) {           /* Strip filename from right. */
        if (ISDIRSEP(s[i-1])) {
            itsadir = 1;
            break;
        }
    }
    debug(F101,"zchko i","",i);
    debug(F101,"zchko itsadir","",itsadir);

#ifdef COMMENT
/* X/OPEN XPG3-compliant systems fail if argument ends with "/"...  */
    if (i == 0)                         /* If no path, use current directory */
      strcpy(s,"./")