1 files changed, 52 insertions, 33 deletions

diff --git a/src/shared/pager.c b/src/shared/pager.c
index 13f03e798b..09672a4abf 100644
--- a/src/shared/pager.c
+++ b/src/shared/pager.c
@@ -1,5 +1,3 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
 /***
   This file is part of systemd.
 
@@ -19,55 +17,67 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <fcntl.h>
+#include <errno.h>
+#include <signal.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
 #include <stdlib.h>
-#include <unistd.h>
 #include <string.h>
 #include <sys/prctl.h>
+#include <unistd.h>
 
+#include "copy.h"
+#include "fd-util.h"
+#include "locale-util.h"
+#include "log.h"
+#include "macro.h"
 #include "pager.h"
-#include "util.h"
 #include "process-util.h"
-#include "macro.h"
-#include "terminal-util.h"
 #include "signal-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "terminal-util.h"
 
 static pid_t pager_pid = 0;
 
 noreturn static void pager_fallback(void) {
-        ssize_t n;
-
-        do {
-                n = splice(STDIN_FILENO, NULL, STDOUT_FILENO, NULL, 64*1024, 0);
-        } while (n > 0);
+        int r;
 
-        if (n < 0) {
-                log_error_errno(errno, "Internal pager failed: %m");
+        r = copy_bytes(STDIN_FILENO, STDOUT_FILENO, (uint64_t) -1, false);
+        if (r < 0) {
+                log_error_errno(r, "Internal pager failed: %m");
                 _exit(EXIT_FAILURE);
         }
 
         _exit(EXIT_SUCCESS);
 }
 
-int pager_open(bool jump_to_end) {
-        int fd[2];
+int pager_open(bool no_pager, bool jump_to_end) {
+        _cleanup_close_pair_ int fd[2] = { -1, -1 };
         const char *pager;
         pid_t parent_pid;
-        int r;
+
+        if (no_pager)
+                return 0;
 
         if (pager_pid > 0)
                 return 1;
 
-        if ((pager = getenv("SYSTEMD_PAGER")) || (pager = getenv("PAGER")))
-                if (!*pager || streq(pager, "cat"))
-                        return 0;
+        if (terminal_is_dumb())
+                return 0;
 
-        if (!on_tty())
+        pager = getenv("SYSTEMD_PAGER");
+        if (!pager)
+                pager = getenv("PAGER");
+
+        /* If the pager is explicitly turned off, honour it */
+        if (pager && STR_IN_SET(pager, "", "cat"))
                 return 0;
 
         /* Determine and cache number of columns before we spawn the
          * pager so that we get the value from the actual tty */
-        columns();
+        (void) columns();
 
         if (pipe(fd) < 0)
                 return log_error_errno(errno, "Failed to create pager pipe: %m");
@@ -75,23 +85,20 @@ int pager_open(bool jump_to_end) {
         parent_pid = getpid();
 
         pager_pid = fork();
-        if (pager_pid < 0) {
-                r = -errno;
-                log_error_errno(errno, "Failed to fork pager: %m");
-                safe_close_pair(fd);
-                return r;
-        }
+        if (pager_pid < 0)
+                return log_error_errno(errno, "Failed to fork pager: %m");
 
         /* In the child start the pager */
         if (pager_pid == 0) {
-                const char* less_opts;
+                const char* less_opts, *less_charset;
 
                 (void) reset_all_signal_handlers();
                 (void) reset_signal_mask();
 
-                dup2(fd[0], STDIN_FILENO);
+                (void) dup2(fd[0], STDIN_FILENO);
                 safe_close_pair(fd);
 
+                /* Initialize a good set of less options */
                 less_opts = getenv("SYSTEMD_LESS");
                 if (!less_opts)
                         less_opts = "FRSXMK";
@@ -99,6 +106,15 @@ int pager_open(bool jump_to_end) {
                         less_opts = strjoina(less_opts, " +G");
                 setenv("LESS", less_opts, 1);
 
+                /* Initialize a good charset for less. This is
+                 * particularly important if we output UTF-8
+                 * characters. */
+                less_charset = getenv("SYSTEMD_LESSCHARSET");
+                if (!less_charset && is_locale_utf8())
+                        less_charset = "utf-8";
+                if (less_charset)
+                        setenv("LESSCHARSET", less_charset, 1);
+
                 /* Make sure the pager goes away when the parent dies */
                 if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
                         _exit(EXIT_FAILURE);
@@ -131,8 +147,9 @@ int pager_open(bool jump_to_end) {
         /* Return in the parent */
         if (dup2(fd[1], STDOUT_FILENO) < 0)
                 return log_error_errno(errno, "Failed to duplicate pager pipe: %m");
+        if (dup2(fd[1], STDERR_FILENO) < 0)
+                return log_error_errno(errno, "Failed to duplicate pager pipe: %m");
 
-        safe_close_pair(fd);
         return 1;
 }
 
@@ -142,8 +159,10 @@ void pager_close(void) {
                 return;
 
         /* Inform pager that we are done */
-        fclose(stdout);
-        kill(pager_pid, SIGCONT);
+        stdout = safe_fclose(stdout);
+        stderr = safe_fclose(stderr);
+
+        (void) kill(pager_pid, SIGCONT);
         (void) wait_for_terminate(pager_pid, NULL);
         pager_pid = 0;
 }