Merge commit 'refs/top-bases/girocco' into girocco
[git/repo.git] / pager.c
blobaa0966c9c55566382bf32c946c0a1846f004125a
1 #include "cache.h"
2 #include "run-command.h"
4 /*
5 * This is split up from the rest of git so that we can do
6 * something different on Windows.
7 */
9 static int spawned_pager;
11 #ifndef __MINGW32__
12 static void pager_preexec(void)
15 * Work around bug in "less" by not starting it until we
16 * have real input
18 fd_set in;
20 FD_ZERO(&in);
21 FD_SET(0, &in);
22 select(1, &in, NULL, &in, NULL);
24 setenv("LESS", "FRSX", 0);
26 #endif
28 static const char *pager_argv[] = { "sh", "-c", NULL, NULL };
29 static struct child_process pager_process;
31 static void wait_for_pager(void)
33 fflush(stdout);
34 fflush(stderr);
35 /* signal EOF to pager */
36 close(1);
37 close(2);
38 finish_command(&pager_process);
41 void setup_pager(void)
43 const char *pager = getenv("GIT_PAGER");
45 if (!isatty(1))
46 return;
47 if (!pager) {
48 if (!pager_program)
49 git_config(git_default_config, NULL);
50 pager = pager_program;
52 if (!pager)
53 pager = getenv("PAGER");
54 if (!pager)
55 pager = "less";
56 else if (!*pager || !strcmp(pager, "cat"))
57 return;
59 spawned_pager = 1; /* means we are emitting to terminal */
61 /* spawn the pager */
62 pager_argv[2] = pager;
63 pager_process.argv = pager_argv;
64 pager_process.in = -1;
65 #ifndef __MINGW32__
66 pager_process.preexec_cb = pager_preexec;
67 #endif
68 if (start_command(&pager_process))
69 return;
71 /* original process continues, but writes to the pipe */
72 dup2(pager_process.in, 1);
73 dup2(pager_process.in, 2);
74 close(pager_process.in);
76 /* this makes sure that the parent terminates after the pager */
77 atexit(wait_for_pager);
80 int pager_in_use(void)
82 const char *env;
84 if (spawned_pager)
85 return 1;
87 env = getenv("GIT_PAGER_IN_USE");
88 return env ? git_config_bool("GIT_PAGER_IN_USE", env) : 0;