diff options
Diffstat (limited to 'pager.c')
-rw-r--r-- | pager.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/pager.c b/pager.c new file mode 100644 index 0000000000..dac358f047 --- /dev/null +++ b/pager.c @@ -0,0 +1,118 @@ +#include "cache.h" +#include "run-command.h" +#include "sigchain.h" + +#ifndef DEFAULT_PAGER +#define DEFAULT_PAGER "less" +#endif + +/* + * This is split up from the rest of git so that we can do + * something different on Windows. + */ + +static int spawned_pager; + +#ifndef WIN32 +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); +} +#endif + +static const char *pager_argv[] = { 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); +} + +const char *git_pager(int stdout_is_tty) +{ + const char *pager; + + if (!stdout_is_tty) + return NULL; + + pager = getenv("GIT_PAGER"); + if (!pager) { + if (!pager_program) + git_config(git_default_config, NULL); + pager = pager_program; + } + if (!pager) + pager = getenv("PAGER"); + if (!pager) + pager = DEFAULT_PAGER; + else if (!*pager || !strcmp(pager, "cat")) + pager = NULL; + + return pager; +} + +void setup_pager(void) +{ + const char *pager = git_pager(isatty(1)); + + if (!pager) + return; + + spawned_pager = 1; /* means we are emitting to terminal */ + + /* spawn the pager */ + pager_argv[0] = pager; + pager_process.use_shell = 1; + pager_process.argv = pager_argv; + pager_process.in = -1; + if (!getenv("LESS")) { + static const char *env[] = { "LESS=FRSX", NULL }; + pager_process.env = env; + } +#ifndef WIN32 + pager_process.preexec_cb = pager_preexec; +#endif + 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("GIT_PAGER_IN_USE"); + return env ? git_config_bool("GIT_PAGER_IN_USE", env) : 0; +} |