[systemd-devel] [PATCH] cgtop: use full terminal width

[Zbigniew Jędrzejewski-Szmek]

---
 src/cgtop/cgtop.c | 10 +++++++---
 src/shared/util.c | 31 ++++++++++++++++++++++++-------
 src/shared/util.h |  1 +
 3 files changed, 32 insertions(+), 10 deletions(-)

diff --git a/src/cgtop/cgtop.c b/src/cgtop/cgtop.c
index 3009589..fde31b9 100644
--- a/src/cgtop/cgtop.c
+++ b/src/cgtop/cgtop.c
@@ -426,7 +426,7 @@ static int display(Hashmap *a) {
         Iterator i;
         Group *g;
         Group **array;
-        unsigned rows, n = 0, j;
+        unsigned rows, path_columns, n = 0, j;
 
         assert(a);
 
@@ -446,6 +446,10 @@ static int display(Hashmap *a) {
         if (rows <= 0)
                 rows = 25;
 
+        path_columns = columns_uncached() - 42;
+        if (path_columns < 10)
+                path_columns = 10;
+
         printf("%s%-37s%s %s%7s%s %s%6s%s %s%8s%s %s%8s%s %s%8s%s\n\n",
                arg_order == ORDER_PATH   ? ANSI_HIGHLIGHT_ON : "", "Path",     arg_order == ORDER_PATH   ? ANSI_HIGHLIGHT_OFF : "",
                arg_order == ORDER_TASKS  ? ANSI_HIGHLIGHT_ON : "", "Tasks",    arg_order == ORDER_TASKS  ? ANSI_HIGHLIGHT_OFF : "",
@@ -463,8 +467,8 @@ static int display(Hashmap *a) {
 
                 g = array[j];
 
-                p = ellipsize(g->path, 37, 33);
-                printf("%-37s", p ? p : g->path);
+                p = ellipsize(g->path, path_columns, 33);
+                printf("%-*s", path_columns, p ? p : g->path);
                 free(p);
 
                 if (g->n_tasks_valid)
diff --git a/src/shared/util.c b/src/shared/util.c
index 5f36008..af97595 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -3774,18 +3774,27 @@ int fd_columns(int fd) {
         return ws.ws_col;
 }
 
-unsigned columns(void) {
-        static __thread int parsed_columns = 0;
+static unsigned columns_cached(bool cached) {
+        static __thread int parsed_columns = 0, env_columns = -1;
         const char *e;
 
-        if (_likely_(parsed_columns > 0))
+        if (_likely_(parsed_columns > 0 && cached))
                 return parsed_columns;
 
-        e = getenv("COLUMNS");
-        if (e)
-                parsed_columns = atoi(e);
+        if (_unlikely_(env_columns == -1)) {
+                e = getenv("COLUMNS");
+                if (e)
+                        env_columns = atoi(e);
+                else
+                        env_columns = 0;
+        }
 
-        if (parsed_columns <= 0)
+        if (env_columns > 0) {
+                parsed_columns = env_columns;
+                return parsed_columns;
+        }
+
+        if (parsed_columns <= 0 || !cached)
                 parsed_columns = fd_columns(STDOUT_FILENO);
 
         if (parsed_columns <= 0)
@@ -3794,6 +3803,14 @@ unsigned columns(void) {
         return parsed_columns;
 }
 
+unsigned columns(void) {
+        return columns_cached(true);
+}
+
+unsigned columns_uncached(void) {
+        return columns_cached(false);
+}
+
 int fd_lines(int fd) {
         struct winsize ws;
         zero(ws);
diff --git a/src/shared/util.h b/src/shared/util.h
index d25b7ee..b315593 100644
--- a/src/shared/util.h
+++ b/src/shared/util.h
@@ -374,6 +374,7 @@ void status_welcome(void);
 
 int fd_columns(int fd);
 unsigned columns(void);
+unsigned columns_uncached(void);
 
 int fd_lines(int fd);
 unsigned lines(void);
-- 
1.7.11.1.282.g511ba53