In
4dc42c6c186 (mingw: refuse paths containing reserved names,
2019-12-21), we started disallowing file names that are reserved, e.g.
`NUL`, `CONOUT$`, etc.
This included `COM<n>` where `<n>` is a digit. Unfortunately, this
includes `COM0` but only `COM1`, ..., `COM9` are reserved, according to
the official documentation, `COM0` is mentioned in the "NT Namespaces"
section but it is explicitly _omitted_ from the list of reserved names:
https://docs.microsoft.com/en-us/windows/win32/fileio/naming-a-file#naming-conventions
Tests corroborate this: it is totally possible to write a file called
`com0.c` on Windows 10, but not `com1.c`.
So let's tighten the code to disallow only the reserved `COM<n>` file
names, but to allow `COM0` again.
This fixes https://github.com/git-for-windows/git/issues/2470.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
continue;
}
break;
- case 'c': case 'C': /* COM<N>, CON, CONIN$, CONOUT$ */
+ case 'c': case 'C':
+ /* COM1 ... COM9, CON, CONIN$, CONOUT$ */
if ((c = path[++i]) != 'o' && c != 'O')
goto not_a_reserved_name;
c = path[++i];
- if (c == 'm' || c == 'M') { /* COM<N> */
- if (!isdigit(path[++i]))
+ if (c == 'm' || c == 'M') { /* COM1 ... COM9 */
+ c = path[++i];
+ if (c < '1' || c > '9')
goto not_a_reserved_name;
} else if (c == 'n' || c == 'N') { /* CON */
c = path[i + 1];
C:\\git \
comm \
conout.c \
+ com0.c \
lptN \
\
--not \
"AUX.c" \
"abc/conOut\$ .xyz/test" \
lpt8 \
+ com9.c \
"lpt*" \
Nul \
"PRN./abc"