top: Add unobtrusive XDG support

By default the file HOME/.toprc will be prefered.  This ensures there
should be minimal breakage even if this file is later created by some
other means.  Otherwise we will follow the new behaviour described by
the XDG Base Directory Specification:

If the XDG_CONFIG_HOME environment variable is available we will attempt
to use this as XDG_CONFIG_HOME/procps/toprc otherwise we will fall-back
to HOME/.config/procps/toprc instead.

Signed-off-by: Earnestly <zibeon@gmail.com>

diff --git a/top/top.1 b/top/top.1
index 23e3a8f618dcdf195706957e38ca0d5858152cb6..a14347d8560e7b27454efcfc5c2bae0086ec43f7 100644 (file)
--- a/top/top.1
+++ b/top/top.1
@@ -69,7 +69,7 @@
 .
 .\" Document /////////////////////////////////////////////////////////////
 .\" ----------------------------------------------------------------------
-.TH TOP 1 "November 2016" "procps-ng" "User Commands"
+.TH TOP 1 "January 2017" "procps-ng" "User Commands"
 .\" ----------------------------------------------------------------------
 
 .\" ----------------------------------------------------------------------
@@ -2195,7 +2195,14 @@ Here is an example of the contents of\fI /etc/toprc\fR:
 .\" ......................................................................
 .SS 6b. PERSONAL Configuration File
 .\" ----------------------------------------------------------------------
-This file is written as `$HOME/.your\-name\-4\-\*(We' + `rc'.
+The legacy version is written as `$HOME/.your\-name\-4\-\*(We' + `rc'
+with a leading period.
+
+A newly created \*(CF is written as procps/your\-name\-4\-\*(We' + `rc'
+without a leading period.
+The procps directory will be subordinate to either $XDG_CONFIG_HOME when
+set as an absolute path or the $HOME/.config directory.
+
 Use the `W' \*(CI to create it or update it.
 
 Here is the general layout:
@@ -2211,8 +2218,8 @@ Here is the general layout:
       "      # discussed below
 .fi
 
-If the $HOME variable is not present, \*(We will try to write the
-personal \*(CF to the current directory, subject to permissions.
+If the $HOME and $XDG_CONFIG_HOME variables are not present, \*(We will try
+to write the personal \*(CF in the current directory, subject to permissions.
 
 .\" ......................................................................
 .SS 6c. ADDING INSPECT Entries

diff --git a/top/top.c b/top/top.c
index 4427f89f00058283ab0405acff29232bd8d79665..3de6510f72b74ab2610972e9813e1628d5c299ac 100644 (file)
--- a/top/top.c
+++ b/top/top.c
@@ -43,6 +43,7 @@
 #include <sys/ioctl.h>
 #include <sys/resource.h>
 #include <sys/select.h>      // also available via <sys/types.h>
+#include <sys/stat.h>
 #include <sys/time.h>
 #include <sys/types.h>       // also available via <stdlib.h>
 
@@ -3458,13 +3459,10 @@ static int config_cvt (WIN_t *q) {
 static void configs_read (void) {
    float tmp_delay = DEF_DELAY;
    char fbuf[LRGBUFSIZ];
-   const char *p;
+   const char *p, *p_home;
    FILE *fp;
    int i;
 
-   p = getenv("HOME");
-   snprintf(Rc_name, sizeof(Rc_name), "%s/.%src", (p && *p) ? p : ".", Myname);
-
    fp = fopen(SYS_RCFILESPEC, "r");
    if (fp) {
       if (fgets(fbuf, sizeof(fbuf), fp)) {     // sys rc file, line 1
@@ -3475,6 +3473,25 @@ static void configs_read (void) {
       fclose(fp);
    }
 
+   // attempt to use the legacy file first, if we cannot access that file, use
+   // the new XDG basedir locations (XDG_CONFIG_HOME or HOME/.config) instead.
+   p_home = getenv("HOME");
+   if (!p_home || p_home[0] == '\0')
+      p_home = ".";
+   snprintf(Rc_name, sizeof(Rc_name), "%s/.%src", p_home, Myname);
+
+   if (access(Rc_name, F_OK)) {
+      p = getenv("XDG_CONFIG_HOME");
+      // ensure the path we get is absolute, fallback otherwise.
+      if (!p || p[0] != '/') {
+         p = fmtmk("%s/.config", p_home);
+         (void)mkdir(p, 0700);
+      }
+      snprintf(Rc_name, sizeof(Rc_name), "%s/procps", p);
+      (void)mkdir(Rc_name, 0700);
+      snprintf(Rc_name, sizeof(Rc_name), "%s/procps/%src", p, Myname);
+   }
+
    fp = fopen(Rc_name, "r");
    if (fp) {
       int tmp_whole, tmp_fract;