4 files changed, 92 insertions, 29 deletions

diff --git a/include/mingw.h b/include/mingw.h
index d77a9beb9..8b295814c 100644
--- a/include/mingw.h
+++ b/include/mingw.h
@@ -528,3 +528,4 @@ int root_len(const char *path);
 char *get_system_drive(void);
 int chdir_system_drive(void);
 char *xabsolute_path(char *path);
+char *get_drive_cwd(const char *path, char *buffer, int size);
diff --git a/libbb/lineedit.c b/libbb/lineedit.c
index 3725dba0d..0d5ce9082 100644
--- a/libbb/lineedit.c
+++ b/libbb/lineedit.c
@@ -843,6 +843,17 @@ static NOINLINE unsigned complete_cmd_dir_file(const char *command, int type)
         path1[0] = (char*)".";
 
         pfind = strrchr(command, '/');
+#if ENABLE_PLATFORM_MINGW32
+        if (!pfind && has_dos_drive_prefix(command) && command[2] != '\0') {
+                char buffer[PATH_MAX];
+
+                /* path is of form c:path with no '/' */
+                if (get_drive_cwd(command, buffer, PATH_MAX)) {
+                        pfind = command + 2;
+                        path1[0] = xstrdup(buffer);
+                }
+        } else
+#endif
         if (!pfind) {
                 if (type == FIND_EXE_ONLY)
                         npaths = path_parse(&paths);
diff --git a/shell/ash.c b/shell/ash.c
index 40965bafa..5f64bebe3 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -2842,6 +2842,7 @@ setprompt_if(smallint do_set, int whichprompt)
 
 #define CD_PHYSICAL 1
 #define CD_PRINT 2
+#define CD_PRINT_ALL 4
 
 static int
 cdopt(void)
@@ -2850,7 +2851,14 @@ cdopt(void)
         int i, j;
 
         j = 'L';
+#if ENABLE_PLATFORM_MINGW32
+        while ((i = nextopt("LPa")) != '\0') {
+                if (i == 'a')
+                        flags |= CD_PRINT_ALL;
+                else
+#else
         while ((i = nextopt("LP")) != '\0') {
+#endif
                 if (i != j) {
                         flags ^= CD_PHYSICAL;
                         j = i;
@@ -2882,56 +2890,62 @@ updatepwd(const char *dir)
         int len = 0;
         /*
          * There are five cases that make some kind of sense
-         *  absdrive +  abspath: c:/path
-         *  absdrive + !abspath: c:path
-         * !absdrive +  abspath: /path
-         * !absdrive +  uncpath: //host/share
-         * !absdrive + !abspath: path
          *
-         * Damn DOS!
-         * c:path behaviour is "undefined"
-         * To properly handle this case, I have to keep track of cwd
-         * of every drive, which is too painful to do.
-         * So when c:path is given, I assume it's c:${curdir}path
-         * with ${curdir} comes from the current drive
+         * Absolute paths:
+         *    c:/path
+         *    //host/share
+         *
+         * Relative to current drive:
+         *    /path
+         *
+         * Relative to current working directory of current drive
+         *    path
+         *
+         * Relative to current working directory of other drive
+         *    c:path
          */
-        int absdrive = *dir && dir[1] == ':';
-        int abspath = absdrive ? is_path_sep(dir[2]) : is_path_sep(*dir);
+        int absdrive = has_dos_drive_prefix(dir);
+        int curr_relpath = !absdrive && !is_path_sep(*dir);
+        int other_relpath = absdrive && !is_path_sep(dir[2]);
+        int relpath = curr_relpath || other_relpath;
 
         cdcomppath = sstrdup(dir);
         STARTSTACKSTR(new);
-        if (!absdrive && curdir == nullstr)
-                return 0;
-        if (!abspath || (is_root(dir) && unc_root_len(curdir))) {
+
+        /* prefix new path with current directory, if required */
+        if (other_relpath) {
+                /* c:path */
+                char buffer[PATH_MAX];
+
+                if (get_drive_cwd(dir, buffer, PATH_MAX) == NULL)
+                        return 0;
+                new = stack_putstr(buffer, new);
+        }
+        else if (curr_relpath || (is_root(dir) && unc_root_len(curdir))) {
+                /* relative path on current drive or explicit root of UNC curdir */
                 if (curdir == nullstr)
                         return 0;
                 new = stack_putstr(curdir, new);
         }
+
         new = makestrspace(strlen(dir) + 2, new);
 
         if ( (len=unc_root_len(dir)) || ((len=unc_root_len(curdir)) &&
-                                (is_root(dir) || (!absdrive && !abspath))) ) {
-                if (is_root(dir))
-                        new = (char *)stackblock() + len;
+                                (is_root(dir) || curr_relpath)) ) {
+                /* //host/share or path relative to //host/share */
                 lim = (char *)stackblock() + len;
         }
         else {
-                char *drive = stackblock();
                 if (absdrive) {
-                        *drive = *dir;
+                        if (!relpath)
+                                new = stack_nputstr(dir, 2, new);
                         cdcomppath += 2;
                         dir += 2;
-                } else {
-                        *drive = *curdir;
                 }
-                drive[1] = ':'; /* in case of absolute drive+path */
-
-                if (abspath)
-                        new = drive + 2;
-                lim = drive + 3;
+                lim = (char *)stackblock() + 3;
         }
 
-        if (!abspath) {
+        if (relpath) {
                 if (!is_path_sep(new[-1]))
                         USTPUTC('/', new);
         } else {
@@ -3160,6 +3174,25 @@ cdcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
         return 0;
 }
 
+#if ENABLE_PLATFORM_MINGW32
+static void
+print_all_cwd(void)
+{
+        FILE *mnt;
+        struct mntent *entry;
+        char buffer[PATH_MAX];
+
+        mnt = setmntent(bb_path_mtab_file, "r");
+        if (mnt) {
+                while ((entry=getmntent(mnt)) != NULL) {
+                        if (get_drive_cwd(entry->mnt_fsname, buffer, PATH_MAX) != NULL)
+                                out1fmt("%s\n", buffer);
+                }
+                endmntent(mnt);
+        }
+}
+#endif
+
 static int FAST_FUNC
 pwdcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
 {
@@ -3167,6 +3200,12 @@ pwdcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
         const char *dir = curdir;
 
         flags = cdopt();
+#if ENABLE_PLATFORM_MINGW32
+        if (flags & CD_PRINT_ALL) {
+                print_all_cwd();
+                return 0;
+        }
+#endif
         if (flags) {
                 if (physdir == nullstr)
                         setpwd(dir, 0);
diff --git a/win32/mingw.c b/win32/mingw.c
index 1d5644f92..ec7d6c456 100644
--- a/win32/mingw.c
+++ b/win32/mingw.c
@@ -1700,3 +1700,15 @@ char *xabsolute_path(char *path)
         }
         bb_perror_msg_and_die("can't open '%s'", path);
 }
+
+char *get_drive_cwd(const char *path, char *buffer, int size)
+{
+        char drive[3] = { *path, ':', '\0' };
+        DWORD ret;
+
+        ret = GetFullPathName(drive, size, buffer, NULL);
+        if (ret == 0 || ret > size)
+                return NULL;
+        bs_to_slash(buffer);
+        return buffer;
+}