mangle.c

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							if (strchr (special, firstpt[1]) != NULL) {
								ivldchar = 1;
								break;
							}
						}
					}
				} else if (lkp[(unsigned char) (*pt)] != *pt) {
					ivldchar = 1;
					break;
				}
				pt++;
			}
		} else {
			ivldchar = 1;
		}
		if (ivldchar
		    || (firstpt == NULL && len > 8)
		    || (len == UMSDOS_EMD_NAMELEN
			&& memcmp (fname, UMSDOS_EMD_FILE, UMSDOS_EMD_NAMELEN) == 0)) {
			/* #Specification: file name / --linux-.---
			 * The name of the EMD file --linux-.--- is map to a mangled
			 * name. So UMSDOS does not restrict its use.
			 */
			/* #Specification: file name / non MSDOS conforming / mangling
			 * Non MSDOS conforming file names must use some alias to fit
			 * in the MSDOS name space.
			 * 
			 * The strategy is simple. The name is simply truncated to
			 * 8 char. points are replace with underscore and a
			 * number is given as an extension. This number correspond
			 * to the entry number in the EMD file. The EMD file
			 * only need to carry the real name.
			 * 
			 * Upper case is also converted to lower case.
			 * Control character are converted to #.
			 * Spaces are converted to #.
			 * The following characters are also converted to #.
			 * #
			 * " * + , / : ; < = > ? [ \ ] | ~
			 * #
			 * 
			 * Sometimes the problem is not in MS-DOS itself but in
			 * command.com.
			 */
			int i;
			char *pt = info->fake.fname;

			base_len = msdos_len = (msdos_len > 8) ? 8 : msdos_len;
			/*
			 * There is no '.' any more so we know for a fact that
			 * the base length is the length.
			 */
			memcpy (info->fake.fname, fname, msdos_len);
			for (i = 0; i < msdos_len; i++, pt++)
				*pt = lkp[(unsigned char) (*pt)];
			*pt = '\0';	/* GLU  We force null termination. */
			info->msdos_reject = 1;
			/*
			 * The numeric extension is added only when we know
			 * the position in the EMD file, in umsdos_newentry(),
			 * umsdos_delentry(), and umsdos_findentry().
			 * See umsdos_manglename().
			 */
		} else {
			/* Conforming MSDOS file name */
			strncpy (info->fake.fname, fname, len);
			info->msdos_reject = 0;
			base_len = firstpt != NULL ? (int) (firstpt - fname) : len;
		}
		if (cardinal_per_size[base_len]) {
			/* #Specification: file name / MSDOS devices / mangling
			 * To avoid unreachable file from MS-DOS, any MS-DOS conforming
			 * file with a basename equal to one of the MS-DOS pseudo
			 * devices will be mangled.
			 * 
			 * If a file such as "prn" was created, it would be unreachable
			 * under MS-DOS because "prn" is assumed to be the printer, even
			 * if the file does have an extension.
			 * 
			 * Since the extension is unimportant to MS-DOS, we must patch
			 * the basename also. We simply insert a minus '-'. To avoid
			 * conflict with valid file with a minus in front (such as
			 * "-prn"), we add an mangled extension like any other
			 * mangled file name.
			 * 
			 * Here is the list of DOS pseudo devices:
			 * 
			 * #
			 * "prn","con","aux","nul",
			 * "lpt1","lpt2","lpt3","lpt4",
			 * "com1","com2","com3","com4",
			 * "clock$"
			 * #
			 * 
			 * and some standard ones for common DOS programs
			 * 
			 * "emmxxxx0","xmsxxxx0","setverxx"
			 * 
			 * (Thanks to Chris Hall <[e-mail]>
			 * for pointing these out to me).
			 * 
			 * Is there one missing?
			 */
			/* This table must be ordered by length */
			static const char *tbdev[] =
			{
				"prn", "con", "aux", "nul",
				"lpt1", "lpt2", "lpt3", "lpt4",
				"com1", "com2", "com3", "com4",
				"clock$",
				"emmxxxx0", "xmsxxxx0", "setverxx"
			};

			/* Tell where to find in tbdev[], the first name of */
			/* a certain length */
			static const char start_ind_dev[9] =
			{
				0, 0, 0, 4, 12, 12, 13, 13, 16
			};
			char basen[9];
			int i;

			for (i = start_ind_dev[base_len - 1]; i < start_ind_dev[base_len]; i++) {
				if (memcmp (info->fake.fname, tbdev[i], base_len) == 0) {
					memcpy (basen, info->fake.fname, base_len);
					basen[base_len] = '\0';		/* GLU  We force null termination. */
					/*
					 * GLU        We do that only if necessary; we try to do the
					 * GLU        simple thing in the usual circumstance. 
					 */
					info->fake.fname[0] = '-';
					strcpy (info->fake.fname + 1, basen);	/* GLU  We already guaranteed a null would be at the end. */
					msdos_len = (base_len == 8) ? 8 : base_len + 1;
					info->msdos_reject = 1;
					break;
				}
			}
		}
		info->fake.fname[msdos_len] = '\0';	/* Help doing printk */
		/* GLU      This zero should (always?) be there already. */
		info->fake.len = msdos_len;
		/* Why not use info->fake.len everywhere? Is it longer?
                 */
		memcpy (info->entry.name, fname, len);
		info->entry.name[len] = '\0';	/* for printk */
		info->entry.name_len = len;
		ret = 0;
	}
	/*
	 * Evaluate how many records are needed to store this entry.
	 */
	info->recsize = umsdos_evalrecsize (len);
	return ret;
}

#ifdef TEST

struct MANG_TEST {
	char *fname;		/* Name to validate */
	int msdos_reject;	/* Expected msdos_reject flag */
	char *msname;		/* Expected msdos name */
};

struct MANG_TEST tb[] =
{
	"hello", 0, "hello",
	"hello.1", 0, "hello.1",
	"hello.1_", 0, "hello.1_",
	"prm", 0, "prm",

#ifdef PROPOSITION
	"HELLO", 1, "hello",
	"Hello.1", 1, "hello.1",
	"Hello.c", 1, "hello.c",
#else
/*
 * I find the three examples below very unfortunate.  I propose to
 * convert them to lower case in a quick preliminary pass, then test
 * whether there are other troublesome characters.  I have not made
 * this change, because it is not easy, but I wanted to mention the 
 * principle.  Obviously something like that would increase the chance
 * of collisions, for example between "HELLO" and "Hello", but these
 * can be treated elsewhere along with the other collisions.
 */

	"HELLO", 1, "hello",
	"Hello.1", 1, "hello_1",
	"Hello.c", 1, "hello_c",
#endif

	"hello.{_1", 1, "hello_{_",
	"hello\t", 1, "hello#",
	"hello.1.1", 1, "hello_1_",
	"hel,lo", 1, "hel#lo",
	"Salut.Tu.vas.bien?", 1, "salut_tu",
	".profile", 1, "_profile",
	".xv", 1, "_xv",
	"toto.", 1, "toto_",
	"clock$.x", 1, "-clock$",
	"emmxxxx0", 1, "-emmxxxx",
	"emmxxxx0.abcd", 1, "-emmxxxx",
	"aux", 1, "-aux",
	"prn", 1, "-prn",
	"prn.abc", 1, "-prn",
	"PRN", 1, "-prn",
  /* 
   * GLU        WARNING:  the results of these are different with my version
   * GLU        of mangling compared to the original one.
   * GLU        CAUSE:  the manner of calculating the baselen variable.
   * GLU                For you they are always 3.
   * GLU                For me they are respectively 7, 8, and 8.

   */
	"PRN.abc", 1, "prn_abc",
	"Prn.abcd", 1, "prn_abcd",
	"prn.abcd", 1, "prn_abcd",
	"Prn.abcdefghij", 1, "prn_abcd"
};

int main (int argc, char *argv[])
{
	int i, rold, rnew;

	printf ("Testing the umsdos_parse.\n");
	for (i = 0; i < sizeof (tb) / sizeof (tb[0]); i++) {
		struct MANG_TEST *pttb = tb + i;
		struct umsdos_info info;
		int ok = umsdos_parse (pttb->fname, strlen (pttb->fname), &info);

		if (strcmp (info.fake.fname, pttb->msname) != 0) {
			printf ("**** %s -> ", pttb->fname);
			printf ("%s <> %s\n", info.fake.fname, pttb->msname);
		} else if (info.msdos_reject != pttb->msdos_reject) {
			printf ("**** %s -> %s ", pttb->fname, pttb->msname);
			printf ("%d <> %d\n", info.msdos_reject, pttb->msdos_reject);
		} else {
			printf ("     %s -> %s %d\n", pttb->fname, pttb->msname
				,pttb->msdos_reject);
		}
	}
	printf ("Testing the new umsdos_evalrecsize.");
	for (i = 0; i < UMSDOS_MAXNAME; i++) {
		rnew = umsdos_evalrecsize (i);
		rold = umsdos_evalrecsize_old (i);
		if (!(i % UMSDOS_REC_SIZE)) {
			printf ("\n%d:\t", i);
		}
		if (rnew != rold) {
			printf ("**** %d newres: %d != %d \n", i, rnew, rold);
		} else {
			printf (".");
		}
	}
	printf ("\nEnd of Testing.\n");

	return 0;
}

#endif