ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/tools/lib/subcmd/pager.c b/marvell/linux/tools/lib/subcmd/pager.c
new file mode 100644
index 0000000..e3d47b5
--- /dev/null
+++ b/marvell/linux/tools/lib/subcmd/pager.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <sys/select.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <signal.h>
+#include <sys/ioctl.h>
+#include "pager.h"
+#include "run-command.h"
+#include "sigchain.h"
+#include "subcmd-config.h"
+
+/*
+ * This is split up from the rest of git so that we can do
+ * something different on Windows.
+ */
+
+static int spawned_pager;
+static int pager_columns;
+
+void pager_init(const char *pager_env)
+{
+ subcmd_config.pager_env = pager_env;
+}
+
+static const char *forced_pager;
+
+void force_pager(const char *pager)
+{
+ forced_pager = pager;
+}
+
+static void pager_preexec(void)
+{
+ /*
+ * Work around bug in "less" by not starting it until we
+ * have real input
+ */
+ fd_set in;
+ fd_set exception;
+
+ FD_ZERO(&in);
+ FD_ZERO(&exception);
+ FD_SET(0, &in);
+ FD_SET(0, &exception);
+ select(1, &in, NULL, &exception, NULL);
+
+ setenv("LESS", "FRSX", 0);
+}
+
+static const char *pager_argv[] = { "sh", "-c", NULL, NULL };
+static struct child_process pager_process;
+
+static void wait_for_pager(void)
+{
+ fflush(stdout);
+ fflush(stderr);
+ /* signal EOF to pager */
+ close(1);
+ close(2);
+ finish_command(&pager_process);
+}
+
+static void wait_for_pager_signal(int signo)
+{
+ wait_for_pager();
+ sigchain_pop(signo);
+ raise(signo);
+}
+
+void setup_pager(void)
+{
+ const char *pager = getenv(subcmd_config.pager_env);
+ struct winsize sz;
+
+ if (forced_pager)
+ pager = forced_pager;
+ if (!isatty(1) && !forced_pager)
+ return;
+ if (ioctl(1, TIOCGWINSZ, &sz) == 0)
+ pager_columns = sz.ws_col;
+ if (!pager)
+ pager = getenv("PAGER");
+ if (!(pager || access("/usr/bin/pager", X_OK)))
+ pager = "/usr/bin/pager";
+ if (!(pager || access("/usr/bin/less", X_OK)))
+ pager = "/usr/bin/less";
+ if (!pager)
+ pager = "cat";
+ if (!*pager || !strcmp(pager, "cat"))
+ return;
+
+ spawned_pager = 1; /* means we are emitting to terminal */
+
+ /* spawn the pager */
+ pager_argv[2] = pager;
+ pager_process.argv = pager_argv;
+ pager_process.in = -1;
+ pager_process.preexec_cb = pager_preexec;
+
+ if (start_command(&pager_process))
+ return;
+
+ /* original process continues, but writes to the pipe */
+ dup2(pager_process.in, 1);
+ if (isatty(2))
+ dup2(pager_process.in, 2);
+ close(pager_process.in);
+
+ /* this makes sure that the parent terminates after the pager */
+ sigchain_push_common(wait_for_pager_signal);
+ atexit(wait_for_pager);
+}
+
+int pager_in_use(void)
+{
+ return spawned_pager;
+}
+
+int pager_get_columns(void)
+{
+ char *s;
+
+ s = getenv("COLUMNS");
+ if (s)
+ return atoi(s);
+
+ return (pager_columns ? pager_columns : 80) - 2;
+}