From 586463c3cf247dbead8553da7284a346b2faf1fb Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Mon, 27 Oct 2014 11:38:43 +0800 Subject: [CD] support drive letters on Cygwin The Cygwin platform supports DOS style drive-letter paths such as "C:\\dir", even though the preferred form is a POSIX-style "/cygdrive/c/dir". This can be seen by doing things such as chdir("c:") (which succeeds) followed by getcwd(NULL, 0) (which returns the normalized "/cygdrive/c"). However, dash was trying to perform local manipulations on the argument to 'cd' prior to calling into libc, in order to update the state of $PWD and friends; these manipulations were assuming that the user meant to change to a relative subdirectory of the current location, as in './c:', instead of honoring the drive letter. None of the other dash builtins take a filename and manipulate it to affect shell state (some, like 'test', take a file name, but as stat("c:") works just fine, there is no need to normalize). This patch has no impact outside of cygwin; on cygwin, it takes advantage of a native function call to canonicalize any incoming name into preferred form before updating shell state. Pre-patch: $ dash -c 'cd c: && echo $PWD' dash: 1: cd: can't cd to c: Post-patch: $ dash -c 'cd c: && echo $PWD' /cygdrive/c Signed-off-by: Eric Blake Signed-off-by: Herbert Xu --- src/cd.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'src') diff --git a/src/cd.c b/src/cd.c index 2d9d4b5..a4e024d 100644 --- a/src/cd.c +++ b/src/cd.c @@ -38,6 +38,9 @@ #include #include #include +#ifdef __CYGWIN__ +#include +#endif /* * The cd and pwd commands. @@ -194,6 +197,17 @@ updatepwd(const char *dir) char *cdcomppath; const char *lim; +#ifdef __CYGWIN__ + /* On cygwin, thanks to drive letters, some absolute paths do + not begin with slash; but cygwin includes a function that + forces normalization to the posix form */ + char pathbuf[PATH_MAX]; + if (cygwin_conv_path(CCP_WIN_A_TO_POSIX | CCP_RELATIVE, dir, pathbuf, + sizeof(pathbuf)) < 0) + sh_error("can't normalize %s", dir); + dir = pathbuf; +#endif + cdcomppath = sstrdup(dir); STARTSTACKSTR(new); if (*dir != '/') { -- cgit 1.4.1