common-main.c

   1 #include "cache.h"
   2 #include "exec-cmd.h"
   3 #include "attr.h"
   4
   5 /*
   6  * Many parts of Git have subprograms communicate via pipe, expect the
   7  * upstream of a pipe to die with SIGPIPE when the downstream of a
   8  * pipe does not need to read all that is written.  Some third-party
   9  * programs that ignore or block SIGPIPE for their own reason forget
  10  * to restore SIGPIPE handling to the default before spawning Git and
  11  * break this carefully orchestrated machinery.
  12  *
  13  * Restore the way SIGPIPE is handled to default, which is what we
  14  * expect.
  15  */
  16 static void restore_sigpipe_to_default(void)
  17 {
  18         sigset_t unblock;
  19
  20         sigemptyset(&unblock);
  21         sigaddset(&unblock, SIGPIPE);
  22         sigprocmask(SIG_UNBLOCK, &unblock, NULL);
  23         signal(SIGPIPE, SIG_DFL);
  24 }
  25
  26 int main(int argc, const char **argv)
  27 {
  28         int result;
  29
  30         trace2_initialize_clock();
  31
  32         /*
  33          * Always open file descriptors 0/1/2 to avoid clobbering files
  34          * in die().  It also avoids messing up when the pipes are dup'ed
  35          * onto stdin/stdout/stderr in the child processes we spawn.
  36          */
  37         sanitize_stdfds();
  38         restore_sigpipe_to_default();
  39
  40         git_resolve_executable_dir(argv[0]);
  41
  42         git_setup_gettext();
  43
  44         initialize_the_repository();
  45
  46         attr_start();
  47
  48         trace2_initialize();
  49         trace2_cmd_start(argv);
  50         trace2_collect_process_info(TRACE2_PROCESS_INFO_STARTUP);
  51
  52         result = cmd_main(argc, argv);
  53
  54         /*
  55          * We define exit() to call trace2_cmd_exit_fl() in
  56          * git-compat-util.h. Whether we reach this or exit()
  57          * elsewhere we'll always run our trace2 exit handler.
  58          */
  59         exit(result);
  60 }