Added file home command for (possible) Tcl 9 TIP 602 migration

1 files changed, 239 insertions, 0 deletions

diff --git a/generic/tclPathObj.c b/generic/tclPathObj.c
index 9524f26..bb269de 100644
--- a/generic/tclPathObj.c
+++ b/generic/tclPathObj.c
@@ -2559,6 +2559,245 @@ TclNativePathInFilesystem(
 }
 
 /*
+ *----------------------------------------------------------------------
+ *
+ * TclGetHomeDir --
+ *
+ *      Returns the home directory of a user.  Note there is a difference
+ *	between not specifying a user and explicitly specifying the current
+ *	user. This mimics Tcl8's tilde expansion.
+ *
+ * Results:
+ *	Returns TCL_OK on success with home directory path in *dsPtr
+ *	and TCL_ERROR on failure with error message in interp if non-NULL.
+ *
+ *----------------------------------------------------------------------
+ */
+int
+TclGetHomeDir(
+    Tcl_Interp *interp, /* May be NULL. Only used for error messages */
+    const char *user,   /* User name. NULL -> current user */
+    Tcl_DString *dsPtr) /* Output. Is initialized by the function. Must be
+                           freed on success */
+{
+    const char *dir;
+    Tcl_DString nativeString;
+
+    Tcl_DStringInit(dsPtr);
+    Tcl_DStringInit(&nativeString);
+
+    if (user == NULL || user[0] == 0) {
+        /* No user name specified -> current user */
+
+	dir = TclGetEnv("HOME", &nativeString);
+	if (dir == NULL) {
+            if (interp) {
+                Tcl_SetObjResult(interp, Tcl_NewStringObj(
+                                     "couldn't find HOME environment variable to"
+                                     " expand path", -1));
+                Tcl_SetErrorCode(interp, "TCL", "VALUE", "PATH",
+                                 "HOMELESS", NULL);
+            }
+            return TCL_ERROR;
+        }
+    } else {
+        /* User name specified - ~user */
+	dir = TclpGetUserHome(user, &nativeString);
+	if (dir == NULL) {
+	    if (interp != NULL) {
+                Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+                                     "user \"%s\" doesn't exist", user));
+                Tcl_SetErrorCode(interp, "TCL", "VALUE", "PATH", "NOUSER",
+                                 NULL);
+            }
+            return TCL_ERROR;
+	}
+    }
+    Tcl_JoinPath(1, &dir, dsPtr);
+
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclGetHomeDirObj --
+ *
+ *	Wrapper around TclGetHomeDir. See that function.
+ *
+ * Results:
+ *      Returns a Tcl_Obj containing the home directory of a user
+ *	or NULL on failure with error message in interp if non-NULL.
+ *
+ *----------------------------------------------------------------------
+ */
+Tcl_Obj *
+TclGetHomeDirObj(
+    Tcl_Interp *interp, /* May be NULL. Only used for error messages */
+    const char *user)   /* User name. NULL -> current user */
+{
+    Tcl_DString dirString;
+
+    if (TclGetHomeDir(interp, user, &dirString) != TCL_OK) {
+	return NULL;
+    }
+    return TclDStringToObj(&dirString);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclResolveTildePath --
+ *
+ *	If the passed path is begins with a tilde, does tilde resolution
+ *	and returns a Tcl_Obj containing the resolved path. If the tilde
+ *	component cannot be resolved, returns NULL. If the path does not
+ *	begin with a tilde, returns as is.
+ *
+ *      The trailing components of the path are returned verbatim. No
+ *	processing is done on them. Moreover, no assumptions should be
+ *	made about the separators in the returned path. They may be /
+ *	or native. Appropriate path manipulations functions should be
+ *	used by caller if desired.
+ *
+ * Results:
+ *      Returns a Tcl_Obj with resolved path. This may be a new Tcl_Obj
+ *	with ref count 0 or that pathObj that was passed in without its
+ *	ref count modified.
+ *      Returns NULL if the path begins with a ~ that cannot be resolved
+ *	and stores an error message in interp if non-NULL.
+ *
+ *----------------------------------------------------------------------
+ */
+Tcl_Obj *
+TclResolveTildePath(
+    Tcl_Interp *interp, /* May be NULL. Only used for error messages */
+    Tcl_Obj *pathObj)
+{
+    const char *path;
+    int len;
+    Tcl_Obj *resolvedObj;
+    Tcl_DString dirString;
+    int split;
+
+    path = Tcl_GetStringFromObj(pathObj, &len);
+    if (path[0] != '~') {
+	return pathObj;
+    }
+
+    /*
+     * We have multiple cases '~/foo/bar...', '~user/foo/bar...', etc.
+     * split becomes value 1 for '~/...' as well as for '~'. Note on
+     * Windows FindSplitPos will implicitly check for '\' as separator
+     * in addition to what is passed.
+     */
+    split = FindSplitPos(path, '/');
+
+    if (split == 1) {
+        /* No user name specified -> current user */
+	if (TclGetHomeDir(interp, NULL, &dirString) != TCL_OK) {
+	    return NULL;
+	}
+    } else {
+        /* User name specified - ~user */
+
+        const char *expandedUser;
+        Tcl_DString userName;
+
+        Tcl_DStringInit(&userName);
+        Tcl_DStringAppend(&userName, path+1, split-1);
+        expandedUser = Tcl_DStringValue(&userName);
+
+	if (TclGetHomeDir(interp, expandedUser, &dirString) != TCL_OK) {
+            Tcl_DStringFree(&userName);
+	    return NULL;
+	}
+        Tcl_DStringFree(&userName);
+    }
+    resolvedObj = TclDStringToObj(&dirString);
+
+    if (split < len) {
+        /* If any trailer, append it verbatim */
+        Tcl_AppendToObj(resolvedObj, split + path, len-split);
+    }
+
+    return resolvedObj;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclResolveTildePathList --
+ *
+ *	Given a Tcl_Obj that is a list of paths, returns a Tcl_Obj containing
+ *	the paths with any ~-prefixed paths resolved.
+ *
+ *	Empty strings and ~-prefixed paths that cannot be resolved are
+ *      removed from the returned list.
+ *
+ *      The trailing components of the path are returned verbatim. No
+ *	processing is done on them. Moreover, no assumptions should be
+ *	made about the separators in the returned path. They may be /
+ *	or native. Appropriate path manipulations functions should be
+ *	used by caller if desired.
+ *
+ * Results:
+ *	Returns a Tcl_Obj with resolved paths. This may be a new Tcl_Obj with
+ *	reference count 0 or the original passed-in Tcl_Obj if no paths needed
+ *	resolution. A NULL is returned if the passed in value is not a list
+ *	or was NULL.
+ *
+ *----------------------------------------------------------------------
+ */
+Tcl_Obj *
+TclResolveTildePathList(
+    Tcl_Obj *pathsObj)
+{
+    Tcl_Obj **objv;
+    int objc;
+    int i;
+    Tcl_Obj *resolvedPaths;
+    const char *path;
+
+    if (pathsObj == NULL) {
+        return NULL;
+    }
+    if (Tcl_ListObjGetElements(NULL, pathsObj, &objc, &objv) != TCL_OK) {
+        return NULL; /* Not a list */
+    }
+
+    /*
+     * Figure out if any paths need resolving to avoid unnecessary allocations.
+     */
+    for (i = 0; i < objc; ++i) {
+        path = Tcl_GetString(objv[i]);
+        if (path[0] == '~') {
+            break; /* At least one path needs resolution */
+        }
+    }
+    if (i == objc) {
+        return pathsObj; /* No paths needed to be resolved */
+    }
+
+    resolvedPaths = Tcl_NewListObj(objc, NULL);
+    for (i = 0; i < objc; ++i) {
+	Tcl_Obj *resolvedPath;
+        path = Tcl_GetString(objv[i]);
+	if (path[0] == 0) {
+	    continue; /* Skip empty strings */
+	}
+	resolvedPath = TclResolveTildePath(NULL, objv[i]);
+	if (resolvedPath) {
+	    /* Paths that cannot be resolved are skipped */
+	    Tcl_ListObjAppendElement(NULL, resolvedPaths, resolvedPath);
+	}
+    }
+
+    return resolvedPaths;
+}
+
+
+/*
  * Local Variables:
  * mode: c
  * c-basic-offset: 4