Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "run-command.h"
   3#include "sigchain.h"
   4
   5/*
   6 * This is split up from the rest of git so that we can do
   7 * something different on Windows.
   8 */
   9
  10static int spawned_pager;
  11
  12#ifndef __MINGW32__
  13static void pager_preexec(void)
  14{
  15        /*
  16         * Work around bug in "less" by not starting it until we
  17         * have real input
  18         */
  19        fd_set in;
  20
  21        FD_ZERO(&in);
  22        FD_SET(0, &in);
  23        select(1, &in, NULL, &in, NULL);
  24
  25        setenv("LESS", "FRSX", 0);
  26}
  27#endif
  28
  29static const char *pager_argv[] = { "sh", "-c", NULL, NULL };
  30static struct child_process pager_process;
  31
  32static void wait_for_pager(void)
  33{
  34        fflush(stdout);
  35        fflush(stderr);
  36        /* signal EOF to pager */
  37        close(1);
  38        close(2);
  39        finish_command(&pager_process);
  40}
  41
  42static void wait_for_pager_signal(int signo)
  43{
  44        wait_for_pager();
  45        sigchain_pop(signo);
  46        raise(signo);
  47}
  48
  49void setup_pager(void)
  50{
  51        const char *pager = getenv("GIT_PAGER");
  52
  53        if (!isatty(1))
  54                return;
  55        if (!pager) {
  56                if (!pager_program)
  57                        git_config(git_default_config, NULL);
  58                pager = pager_program;
  59        }
  60        if (!pager)
  61                pager = getenv("PAGER");
  62        if (!pager)
  63                pager = "less";
  64        else if (!*pager || !strcmp(pager, "cat"))
  65                return;
  66
  67        spawned_pager = 1; /* means we are emitting to terminal */
  68
  69        /* spawn the pager */
  70        pager_argv[2] = pager;
  71        pager_process.argv = pager_argv;
  72        pager_process.in = -1;
  73#ifndef __MINGW32__
  74        pager_process.preexec_cb = pager_preexec;
  75#endif
  76        if (start_command(&pager_process))
  77                return;
  78
  79        /* original process continues, but writes to the pipe */
  80        dup2(pager_process.in, 1);
  81        if (isatty(2))
  82                dup2(pager_process.in, 2);
  83        close(pager_process.in);
  84
  85        /* this makes sure that the parent terminates after the pager */
  86        sigchain_push_common(wait_for_pager_signal);
  87        atexit(wait_for_pager);
  88}
  89
  90int pager_in_use(void)
  91{
  92        const char *env;
  93
  94        if (spawned_pager)
  95                return 1;
  96
  97        env = getenv("GIT_PAGER_IN_USE");
  98        return env ? git_config_bool("GIT_PAGER_IN_USE", env) : 0;
  99}