mirror of https://gitee.com/openkylin/linux.git
96 lines
1.8 KiB
C
96 lines
1.8 KiB
C
#include "cache.h"
|
|
#include "run-command.h"
|
|
#include "sigchain.h"
|
|
|
|
/*
|
|
* This is split up from the rest of git so that we can do
|
|
* something different on Windows.
|
|
*/
|
|
|
|
static int spawned_pager;
|
|
|
|
static void pager_preexec(void)
|
|
{
|
|
/*
|
|
* Work around bug in "less" by not starting it until we
|
|
* have real input
|
|
*/
|
|
fd_set in;
|
|
|
|
FD_ZERO(&in);
|
|
FD_SET(0, &in);
|
|
select(1, &in, NULL, &in, NULL);
|
|
|
|
setenv("LESS", "FRSX", 0);
|
|
}
|
|
|
|
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)
|
|
{
|
|
const char *pager = getenv("PERF_PAGER");
|
|
|
|
if (!isatty(1))
|
|
return;
|
|
if (!pager)
|
|
pager = getenv("PAGER");
|
|
if (!(pager || access("/usr/bin/pager", X_OK)))
|
|
pager = "/usr/bin/pager";
|
|
if (!(pager || access("/usr/bin/less", X_OK)))
|
|
pager = "/usr/bin/less";
|
|
if (!pager)
|
|
pager = "cat";
|
|
if (!*pager || !strcmp(pager, "cat"))
|
|
return;
|
|
|
|
spawned_pager = 1; /* means we are emitting to terminal */
|
|
|
|
/* spawn the pager */
|
|
pager_argv[2] = pager;
|
|
pager_process.argv = pager_argv;
|
|
pager_process.in = -1;
|
|
pager_process.preexec_cb = pager_preexec;
|
|
|
|
if (start_command(&pager_process))
|
|
return;
|
|
|
|
/* 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);
|
|
|
|
/* 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)
|
|
{
|
|
const char *env;
|
|
|
|
if (spawned_pager)
|
|
return 1;
|
|
|
|
env = getenv("PERF_PAGER_IN_USE");
|
|
return env ? perf_config_bool("PERF_PAGER_IN_USE", env) : 0;
|
|
}
|