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[git/git.git] / pager.c
CommitLineData
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1#include "cache.h"
2
3/*
4 * This is split up from the rest of git so that we might do
5 * something different on Windows, for example.
6 */
7
402461aa 8static void run_pager(const char *pager)
f67b45f8 9{
402461aa 10 execlp(pager, pager, NULL);
34fd1c9a 11 execl("/bin/sh", "sh", "-c", pager, NULL);
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12}
13
14void setup_pager(void)
15{
16 pid_t pid;
17 int fd[2];
402461aa 18 const char *pager = getenv("PAGER");
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19
20 if (!isatty(1))
21 return;
402461aa
JS
22 if (!pager)
23 pager = "less";
caef71a5 24 else if (!*pager || !strcmp(pager, "cat"))
402461aa
JS
25 return;
26
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27 if (pipe(fd) < 0)
28 return;
29 pid = fork();
30 if (pid < 0) {
31 close(fd[0]);
32 close(fd[1]);
33 return;
34 }
35
36 /* return in the child */
37 if (!pid) {
38 dup2(fd[1], 1);
39 close(fd[0]);
40 close(fd[1]);
41 return;
42 }
43
44 /* The original process turns into the PAGER */
45 dup2(fd[0], 0);
46 close(fd[0]);
47 close(fd[1]);
48
cd112cef 49 setenv("LESS", "-RS", 0);
402461aa 50 run_pager(pager);
34fd1c9a 51 die("unable to execute pager '%s'", pager);
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52 exit(255);
53}