strv: add new STR_IN_SET() macro that operates similar to IN_SET() but for strings

[elogind.git] / src / shared / pager.c

diff --git a/src/shared/pager.c b/src/shared/pager.c
index 36b409c07031932843c5994209d8daa3bed44fc9..55b13d6ff63ecbf80198b5d9144c12fa5474320d 100644 (file)
--- a/src/shared/pager.c
+++ b/src/shared/pager.c
@@ -32,32 +32,36 @@
 
 static pid_t pager_pid = 0;
 
-_noreturn_ static void pager_fallback(void) {
+noreturn static void pager_fallback(void) {
         ssize_t n;
+
         do {
                 n = splice(STDIN_FILENO, NULL, STDOUT_FILENO, NULL, 64*1024, 0);
         } while (n > 0);
+
         if (n < 0) {
                 log_error("Internal pager failed: %m");
                 _exit(EXIT_FAILURE);
         }
+
         _exit(EXIT_SUCCESS);
 }
 
-bool pager_open(void) {
+int pager_open(bool jump_to_end) {
         int fd[2];
         const char *pager;
         pid_t parent_pid;
+        int r;
 
         if (pager_pid > 0)
-                return false;
+                return 1;
 
         if ((pager = getenv("SYSTEMD_PAGER")) || (pager = getenv("PAGER")))
                 if (!*pager || streq(pager, "cat"))
-                        return false;
+                        return 0;
 
-        if (isatty(STDOUT_FILENO) <= 0)
-                return false;
+        if (!on_tty())
+                return 0;
 
         /* Determine and cache number of columns before we spawn the
          * pager so that we get the value from the actual tty */
@@ -65,25 +69,32 @@ bool pager_open(void) {
 
         if (pipe(fd) < 0) {
                 log_error("Failed to create pager pipe: %m");
-                return false;
+                return -errno;
         }
 
         parent_pid = getpid();
 
         pager_pid = fork();
         if (pager_pid < 0) {
+                r = -errno;
                 log_error("Failed to fork pager: %m");
                 close_pipe(fd);
-                return false;
+                return r;
         }
 
         /* In the child start the pager */
         if (pager_pid == 0) {
+                const char* less_opts;
 
                 dup2(fd[0], STDIN_FILENO);
                 close_pipe(fd);
 
-                setenv("LESS", "FRSX", 0);
+                less_opts = getenv("SYSTEMD_LESS");
+                if (!less_opts)
+                        less_opts = "FRSXMK";
+                if (jump_to_end)
+                        less_opts = strappenda(less_opts, " +G");
+                setenv("LESS", less_opts, 1);
 
                 /* Make sure the pager goes away when the parent dies */
                 if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
@@ -117,11 +128,11 @@ bool pager_open(void) {
         /* Return in the parent */
         if (dup2(fd[1], STDOUT_FILENO) < 0) {
                 log_error("Failed to duplicate pager pipe: %m");
-                return false;
+                return -errno;
         }
 
         close_pipe(fd);
-        return true;
+        return 1;
 }
 
 void pager_close(void) {
@@ -135,3 +146,7 @@ void pager_close(void) {
         wait_for_terminate(pager_pid, NULL);
         pager_pid = 0;
 }
+
+bool pager_have(void) {
+        return pager_pid > 0;
+}