Prep v234: Apply missing upstream fixes in src/login (3/6)

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

diff --git a/src/shared/pager.c b/src/shared/pager.c
index 0e21065076e50cf0676fd85b52bf5886220a5928..8f3fc133ba29dab4899ace53d5cbe1c145e8bb99 100644 (file)
--- a/src/shared/pager.c
+++ b/src/shared/pager.c
@@ -36,6 +36,7 @@
 #include "process-util.h"
 #include "signal-util.h"
 #include "string-util.h"
+#include "strv.h"
 #include "terminal-util.h"
 
 static pid_t pager_pid = 0;
@@ -43,7 +44,7 @@ static pid_t pager_pid = 0;
 noreturn static void pager_fallback(void) {
         int r;
 
-        r = copy_bytes(STDIN_FILENO, STDOUT_FILENO, (uint64_t) -1, false);
+        r = copy_bytes(STDIN_FILENO, STDOUT_FILENO, (uint64_t) -1, 0);
         if (r < 0) {
                 log_error_errno(r, "Internal pager failed: %m");
                 _exit(EXIT_FAILURE);
@@ -52,23 +53,31 @@ noreturn static void pager_fallback(void) {
         _exit(EXIT_SUCCESS);
 }
 
-int pager_open(bool jump_to_end) {
+static int stored_stdout = -1;
+static int stored_stderr = -1;
+static bool stdout_redirected = false;
+static bool stderr_redirected = false;
+
+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;
 
+        if (no_pager)
+                return 0;
+
         if (pager_pid > 0)
                 return 1;
 
-        if (!on_tty())
-                        return 0;
+        if (terminal_is_dumb())
+                return 0;
 
         pager = getenv("SYSTEMD_PAGER");
         if (!pager)
                 pager = getenv("PAGER");
 
         /* If the pager is explicitly turned off, honour it */
-        if (pager && (pager[0] == 0 || streq(pager, "cat")))
+        if (pager && STR_IN_SET(pager, "", "cat"))
                 return 0;
 
         /* Determine and cache number of columns before we spawn the
@@ -100,7 +109,8 @@ int pager_open(bool jump_to_end) {
                         less_opts = "FRSXMK";
                 if (jump_to_end)
                         less_opts = strjoina(less_opts, " +G");
-                setenv("LESS", less_opts, 1);
+                if (setenv("LESS", less_opts, 1) < 0)
+                        _exit(EXIT_FAILURE);
 
                 /* Initialize a good charset for less. This is
                  * particularly important if we output UTF-8
@@ -108,8 +118,9 @@ int pager_open(bool jump_to_end) {
                 less_charset = getenv("SYSTEMD_LESSCHARSET");
                 if (!less_charset && is_locale_utf8())
                         less_charset = "utf-8";
-                if (less_charset)
-                        setenv("LESSCHARSET", less_charset, 1);
+                if (less_charset &&
+                    setenv("LESSCHARSET", less_charset, 1) < 0)
+                        _exit(EXIT_FAILURE);
 
                 /* Make sure the pager goes away when the parent dies */
                 if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
@@ -141,10 +152,19 @@ int pager_open(bool jump_to_end) {
         }
 
         /* Return in the parent */
-        if (dup2(fd[1], STDOUT_FILENO) < 0)
+        stored_stdout = fcntl(STDOUT_FILENO, F_DUPFD_CLOEXEC, 3);
+        if (dup2(fd[1], STDOUT_FILENO) < 0) {
+                stored_stdout = safe_close(stored_stdout);
                 return log_error_errno(errno, "Failed to duplicate pager pipe: %m");
-        if (dup2(fd[1], STDERR_FILENO) < 0)
+        }
+        stdout_redirected = true;
+
+        stored_stderr = fcntl(STDERR_FILENO, F_DUPFD_CLOEXEC, 3);
+        if (dup2(fd[1], STDERR_FILENO) < 0) {
+                stored_stderr = safe_close(stored_stderr);
                 return log_error_errno(errno, "Failed to duplicate pager pipe: %m");
+        }
+        stderr_redirected = true;
 
         return 1;
 }
@@ -155,13 +175,17 @@ void pager_close(void) {
                 return;
 
         /* Inform pager that we are done */
-#if defined(__GLIBC__)
-        stdout = safe_fclose(stdout);
-        stderr = safe_fclose(stderr);
-#else
-        (void) safe_fclose(stdout);
-        (void) safe_fclose(stderr);
-#endif // in musl-libc these are const
+        (void) fflush(stdout);
+        if (stdout_redirected)
+                if (stored_stdout < 0 || dup2(stored_stdout, STDOUT_FILENO) < 0)
+                        (void) close(STDOUT_FILENO);
+        stored_stdout = safe_close(stored_stdout);
+        (void) fflush(stderr);
+        if (stderr_redirected)
+                if (stored_stderr < 0 || dup2(stored_stderr, STDERR_FILENO) < 0)
+                        (void) close(STDERR_FILENO);
+        stored_stderr = safe_close(stored_stderr);
+        stdout_redirected = stderr_redirected = false;
 
         (void) kill(pager_pid, SIGCONT);
         (void) wait_for_terminate(pager_pid, NULL);