shared: explicitly ignore the return value of wait_for_terminate

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

diff --git a/src/shared/pager.c b/src/shared/pager.c
index 6799787e85b0cf7d339e23d553b328b6fbd9d3ab..001927ce93e093e26a210a9326826e16d9c57b02 100644 (file)
--- a/src/shared/pager.c
+++ b/src/shared/pager.c
@@ -32,19 +32,22 @@
 
 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);
 }
 
-int pager_open(void) {
+int pager_open(bool jump_to_end) {
         int fd[2];
         const char *pager;
         pid_t parent_pid;
@@ -57,7 +60,7 @@ int pager_open(void) {
                 if (!*pager || streq(pager, "cat"))
                         return 0;
 
-        if (isatty(STDOUT_FILENO) <= 0)
+        if (!on_tty())
                 return 0;
 
         /* Determine and cache number of columns before we spawn the
@@ -75,17 +78,23 @@ int pager_open(void) {
         if (pager_pid < 0) {
                 r = -errno;
                 log_error("Failed to fork pager: %m");
-                close_pipe(fd);
+                safe_close_pair(fd);
                 return r;
         }
 
         /* In the child start the pager */
         if (pager_pid == 0) {
+                const char* less_opts;
 
                 dup2(fd[0], STDIN_FILENO);
-                close_pipe(fd);
+                safe_close_pair(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)
@@ -122,7 +131,7 @@ int pager_open(void) {
                 return -errno;
         }
 
-        close_pipe(fd);
+        safe_close_pair(fd);
         return 1;
 }
 
@@ -134,10 +143,63 @@ void pager_close(void) {
         /* Inform pager that we are done */
         fclose(stdout);
         kill(pager_pid, SIGCONT);
-        wait_for_terminate(pager_pid, NULL);
+        (void) wait_for_terminate(pager_pid, NULL);
         pager_pid = 0;
 }
 
 bool pager_have(void) {
         return pager_pid > 0;
 }
+
+int show_man_page(const char *desc, bool null_stdio) {
+        const char *args[4] = { "man", NULL, NULL, NULL };
+        char *e = NULL;
+        pid_t pid;
+        size_t k;
+        int r;
+        siginfo_t status;
+
+        k = strlen(desc);
+
+        if (desc[k-1] == ')')
+                e = strrchr(desc, '(');
+
+        if (e) {
+                char *page = NULL, *section = NULL;
+
+                page = strndupa(desc, e - desc);
+                section = strndupa(e + 1, desc + k - e - 2);
+
+                args[1] = section;
+                args[2] = page;
+        } else
+                args[1] = desc;
+
+        pid = fork();
+        if (pid < 0) {
+                log_error("Failed to fork: %m");
+                return -errno;
+        }
+
+        if (pid == 0) {
+                /* Child */
+                if (null_stdio) {
+                        r = make_null_stdio();
+                        if (r < 0) {
+                                log_error("Failed to kill stdio: %s", strerror(-r));
+                                _exit(EXIT_FAILURE);
+                        }
+                }
+
+                execvp(args[0], (char**) args);
+                log_error("Failed to execute man: %m");
+                _exit(EXIT_FAILURE);
+        }
+
+        r = wait_for_terminate(pid, &status);
+        if (r < 0)
+                return r;
+
+        log_debug("Exit code %i status %i", status.si_code, status.si_status);
+        return status.si_status;
+}