common-main.c

   1 #define USE_THE_REPOSITORY_VARIABLE
   2
   3 #include "git-compat-util.h"
   4 #include "exec-cmd.h"
   5 #include "gettext.h"
   6 #include "attr.h"
   7 #include "repository.h"
   8 #include "setup.h"
   9 #include "strbuf.h"
  10 #include "trace2.h"
  11
  12 /*
  13  * Many parts of Git have subprograms communicate via pipe, expect the
  14  * upstream of a pipe to die with SIGPIPE when the downstream of a
  15  * pipe does not need to read all that is written.  Some third-party
  16  * programs that ignore or block SIGPIPE for their own reason forget
  17  * to restore SIGPIPE handling to the default before spawning Git and
  18  * break this carefully orchestrated machinery.
  19  *
  20  * Restore the way SIGPIPE is handled to default, which is what we
  21  * expect.
  22  */
  23 static void restore_sigpipe_to_default(void)
  24 {
  25         sigset_t unblock;
  26
  27         sigemptyset(&unblock);
  28         sigaddset(&unblock, SIGPIPE);
  29         sigprocmask(SIG_UNBLOCK, &unblock, NULL);
  30         signal(SIGPIPE, SIG_DFL);
  31 }
  32
  33 int main(int argc, const char **argv)
  34 {
  35         int result;
  36         struct strbuf tmp = STRBUF_INIT;
  37
  38         trace2_initialize_clock();
  39
  40         /*
  41          * Always open file descriptors 0/1/2 to avoid clobbering files
  42          * in die().  It also avoids messing up when the pipes are dup'ed
  43          * onto stdin/stdout/stderr in the child processes we spawn.
  44          */
  45         sanitize_stdfds();
  46         restore_sigpipe_to_default();
  47
  48         git_resolve_executable_dir(argv[0]);
  49
  50         setlocale(LC_CTYPE, "");
  51         git_setup_gettext();
  52
  53         initialize_repository(the_repository);
  54
  55         attr_start();
  56
  57         trace2_initialize();
  58         trace2_cmd_start(argv);
  59         trace2_collect_process_info(TRACE2_PROCESS_INFO_STARTUP);
  60
  61         if (!strbuf_getcwd(&tmp))
  62                 tmp_original_cwd = strbuf_detach(&tmp, NULL);
  63
  64         result = cmd_main(argc, argv);
  65
  66         /* Not exit(3), but a wrapper calling our common_exit() */
  67         exit(result);
  68 }
  69
  70 static void check_bug_if_BUG(void)
  71 {
  72         if (!bug_called_must_BUG)
  73                 return;
  74         BUG("on exit(): had bug() call(s) in this process without explicit BUG_if_bug()");
  75 }
  76
  77 /* We wrap exit() to call common_exit() in git-compat-util.h */
  78 int common_exit(const char *file, int line, int code)
  79 {
  80         /*
  81          * For non-POSIX systems: Take the lowest 8 bits of the "code"
  82          * to e.g. turn -1 into 255. On a POSIX system this is
  83          * redundant, see exit(3) and wait(2), but as it doesn't harm
  84          * anything there we don't need to guard this with an "ifdef".
  85          */
  86         code &= 0xff;
  87
  88         check_bug_if_BUG();
  89         trace2_cmd_exit_fl(file, line, code);
  90
  91         return code;
  92 }