systemctl: try harder to find a suitable pager

diff --git a/src/systemctl.c b/src/systemctl.c
index 585f1dc5fee1d56670a9c0089187a78ead227013..8a6277e75c62a941822ba7a8bd7313788371e456 100644 (file)
--- a/src/systemctl.c
+++ b/src/systemctl.c
@@ -4251,7 +4251,7 @@ static int systemctl_parse_argv(int argc, char *argv[]) {
                 ARG_SYSTEM,
                 ARG_GLOBAL,
                 ARG_NO_BLOCK,
-               ARG_NO_PAGER,
+                ARG_NO_PAGER,
                 ARG_NO_WALL,
                 ARG_ORDER,
                 ARG_REQUIRE,
@@ -4352,9 +4352,9 @@ static int systemctl_parse_argv(int argc, char *argv[]) {
                         arg_no_block = true;
                         break;
 
-               case ARG_NO_PAGER:
-                       arg_no_pager = true;
-                       break;
+                case ARG_NO_PAGER:
+                        arg_no_pager = true;
+                        break;
 
                 case ARG_NO_WALL:
                         arg_no_wall = true;
@@ -5283,45 +5283,56 @@ static int runlevel_main(void) {
 }
 
 static void pager_open(void) {
-       pid_t pid;
-       int fd[2];
-       const char *pager = getenv("PAGER");
-
-       if (!on_tty() || arg_no_pager)
-               return;
-       if (!pager)
-               pager = "less";
-       else if (!*pager || !strcmp(pager, "cat"))
-               return;
-
-       if (pipe(fd) < 0)
-               return;
-       pid = fork();
-       if (pid < 0) {
-               close(fd[0]);
-               close(fd[1]);
-               return;
-       }
-
-       /* Return in the child */
-       if (!pid) {
-               dup2(fd[1], 1);
-               close(fd[0]);
-               close(fd[1]);
-               return;
-       }
-
-       /* The original process turns into the PAGER */
-       dup2(fd[0], 0);
-       close(fd[0]);
-       close(fd[1]);
-
-       setenv("LESS", "FRSX", 0);
-       execlp(pager, pager, NULL);
-       execl("/bin/sh", "sh", "-c", pager, NULL);
-
-       log_error("unable to execute pager '%s'", pager);
-       _exit(EXIT_FAILURE);
+        pid_t pid;
+        int fd[2];
+        const char *pager;
+
+        if (!on_tty() || arg_no_pager)
+                return;
+
+        if ((pager = getenv("PAGER")))
+                if (!*pager || streq(pager, "cat"))
+                        return;
+
+        if (pipe(fd) < 0) {
+                log_error("Failed to create pager pipe: %m");
+                return;
+        }
+
+        pid = fork();
+        if (pid < 0) {
+                log_error("Failed to fork pager: %m");
+                close_pipe(fd);
+                return;
+        }
+
+        /* The original process turns into the PAGER */
+        if (pid != 0) {
+
+                dup2(fd[0], STDIN_FILENO);
+                close_pipe(fd);
+
+                if (!getenv("LESS"))
+                        setenv("LESS", "FRSX", 0);
+
+                if (pager) {
+                        execlp(pager, pager, NULL);
+                        execl("/bin/sh", "sh", "-c", pager, NULL);
+                } else {
+                        execlp("sensible-pager", "sensible-pager", NULL);
+                        execlp("less", "less", NULL);
+                        execlp("more", "more", NULL);
+                }
+
+                log_error("Unable to execute pager: %m");
+                _exit(EXIT_FAILURE);
+        }
+
+        /* Return in the child */
+        if (dup2(fd[1], STDOUT_FILENO) < 0)
+                log_error("Failed to duplicate pager pipe: %m");
+
+        close_pipe(fd);
 }
 
 int main(int argc, char*argv[]) {
@@ -5341,7 +5352,7 @@ int main(int argc, char*argv[]) {
                 goto finish;
         }
 
-       pager_open();
+        pager_open();
 
         /* /sbin/runlevel doesn't need to communicate via D-Bus, so
          * let's shortcut this */