git add: trivial codestyle cleanup

[git.git] / pager.c

diff --git a/pager.c b/pager.c
index dbd941421bf90bb1c4b6ad26ba46869f57d15cd8..4921843577e42b774457a61277b9bc3441d3ab6b 100644 (file)
--- a/pager.c
+++ b/pager.c
@@ -1,13 +1,16 @@
 #include "cache.h"
+#include "run-command.h"
+#include "sigchain.h"
 
 /*
- * This is split up from the rest of git so that we might do
- * something different on Windows, for example.
+ * This is split up from the rest of git so that we can do
+ * something different on Windows.
  */
 
 static int spawned_pager;
 
-static void run_pager(const char *pager)
+#ifndef __MINGW32__
+static void pager_preexec(void)
 {
        /*
         * Work around bug in "less" by not starting it until we
@@ -19,14 +22,32 @@ static void run_pager(const char *pager)
        FD_SET(0, &in);
        select(1, &in, NULL, &in, NULL);
 
-       execlp(pager, pager, NULL);
-       execl("/bin/sh", "sh", "-c", pager, NULL);
+       setenv("LESS", "FRSX", 0);
+}
+#endif
+
+static const char *pager_argv[] = { "sh", "-c", NULL, NULL };
+static struct child_process pager_process;
+
+static void wait_for_pager(void)
+{
+       fflush(stdout);
+       fflush(stderr);
+       /* signal EOF to pager */
+       close(1);
+       close(2);
+       finish_command(&pager_process);
+}
+
+static void wait_for_pager_signal(int signo)
+{
+       wait_for_pager();
+       sigchain_pop(signo);
+       raise(signo);
 }
 
 void setup_pager(void)
 {
-       pid_t pid;
-       int fd[2];
        const char *pager = getenv("GIT_PAGER");
 
        if (!isatty(1))
@@ -45,33 +66,25 @@ void setup_pager(void)
 
        spawned_pager = 1; /* means we are emitting to terminal */
 
-       if (pipe(fd) < 0)
-               return;
-       pid = fork();
-       if (pid < 0) {
-               close(fd[0]);
-               close(fd[1]);
+       /* spawn the pager */
+       pager_argv[2] = pager;
+       pager_process.argv = pager_argv;
+       pager_process.in = -1;
+#ifndef __MINGW32__
+       pager_process.preexec_cb = pager_preexec;
+#endif
+       if (start_command(&pager_process))
                return;
-       }
 
-       /* return in the child */
-       if (!pid) {
-               dup2(fd[1], 1);
-               dup2(fd[1], 2);
-               close(fd[0]);
-               close(fd[1]);
-               return;
-       }
-
-       /* The original process turns into the PAGER */
-       dup2(fd[0], 0);
-       close(fd[0]);
-       close(fd[1]);
+       /* original process continues, but writes to the pipe */
+       dup2(pager_process.in, 1);
+       if (isatty(2))
+               dup2(pager_process.in, 2);
+       close(pager_process.in);
 
-       setenv("LESS", "FRSX", 0);
-       run_pager(pager);
-       die("unable to execute pager '%s'", pager);
-       exit(255);
+       /* this makes sure that the parent terminates after the pager */
+       sigchain_push_common(wait_for_pager_signal);
+       atexit(wait_for_pager);
 }
 
 int pager_in_use(void)