[PATCH 1/7] Move term_columns() to pager.c and save terminal width before pager

["Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>]

term_columns() checks for terminal width via ioctl(1). After
redirecting, stdin is no longer terminal to get terminal width.

Check terminal width and save it before redirect stdin in setup_pager()
and let term_columns() reuse the value.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 cache.h |    1 +
 help.c  |   22 ----------------------
 pager.c |   32 ++++++++++++++++++++++++++++++++
 3 files changed, 33 insertions(+), 22 deletions(-)

diff --git a/cache.h b/cache.h
index d83d68c..bcbd5f2 100644
--- a/cache.h
+++ b/cache.h
@@ -1045,6 +1045,7 @@ extern void setup_pager(void);
 extern const char *pager_program;
 extern int pager_in_use(void);
 extern int pager_use_color;
+extern int term_columns();
 
 extern const char *editor_program;
 extern const char *askpass_program;
diff --git a/help.c b/help.c
index 7654f1b..1344208 100644
--- a/help.c
+++ b/help.c
@@ -5,28 +5,6 @@
 #include "help.h"
 #include "common-cmds.h"
 
-/* most GUI terminals set COLUMNS (although some don't export it) */
-static int term_columns(void)
-{
-	char *col_string = getenv("COLUMNS");
-	int n_cols;
-
-	if (col_string && (n_cols = atoi(col_string)) > 0)
-		return n_cols;
-
-#ifdef TIOCGWINSZ
-	{
-		struct winsize ws;
-		if (!ioctl(1, TIOCGWINSZ, &ws)) {
-			if (ws.ws_col)
-				return ws.ws_col;
-		}
-	}
-#endif
-
-	return 80;
-}
-
 void add_cmdname(struct cmdnames *cmds, const char *name, int len)
 {
 	struct cmdname *ent = xmalloc(sizeof(*ent) + len + 1);
diff --git a/pager.c b/pager.c
index dac358f..ad447cf 100644
--- a/pager.c
+++ b/pager.c
@@ -12,6 +12,7 @@
  */
 
 static int spawned_pager;
+static int max_columns;
 
 #ifndef WIN32
 static void pager_preexec(void)
@@ -80,6 +81,15 @@ void setup_pager(void)
 
 	spawned_pager = 1; /* means we are emitting to terminal */
 
+#ifdef TIOCGWINSZ
+	{
+		struct winsize ws;
+		if (!ioctl(1, TIOCGWINSZ, &ws)) {
+			if (ws.ws_col)
+				max_columns = ws.ws_col;
+		}
+	}
+#endif
 	/* spawn the pager */
 	pager_argv[0] = pager;
 	pager_process.use_shell = 1;
@@ -116,3 +126,25 @@ int pager_in_use(void)
 	env = getenv("GIT_PAGER_IN_USE");
 	return env ? git_config_bool("GIT_PAGER_IN_USE", env) : 0;
 }
+
+int term_columns()
+{
+	char *col_string = getenv("COLUMNS");
+	int n_cols;
+
+	if (col_string && (n_cols = atoi(col_string)) > 0)
+		return n_cols;
+
+	else if (spawned_pager && max_columns)
+		return max_columns;
+#ifdef TIOCGWINSZ
+	else {
+		struct winsize ws;
+		if (!ioctl(1, TIOCGWINSZ, &ws)) {
+			if (ws.ws_col)
+				return ws.ws_col;
+		}
+	}
+#endif
+	return 80;
+}
-- 
1.7.2.2