XD/XD.c

#include <stdio.h>
#include <stdlib.h>
#ifdef ERR
#include <stdarg.h>
#include <string.h>
#endif

#ifdef GIT
#include <git2.h>
#include <git2/common.h>
#include <git2/errors.h>
#include <git2/global.h>
#include <git2/refs.h>
#include <git2/repository.h>
#include <git2/status.h>
#endif

enum face { EYES, NOSE, MOUTH };

void
l(const char *fmt, ...)
{
  #ifdef ERR
	va_list ap;

	va_start(ap, fmt);
	vfprintf(stderr, fmt, ap);
	va_end(ap);

	if (fmt[0] && fmt[strlen(fmt) - 1] == ':') {
		fputc(' ', stderr);
		perror(NULL);
	} else {
		fputc('\n', stderr);
	}
  #endif
}

#ifdef GIT
/**
 * @brief open git repo if one is available at the current path
 *
 * @return a pointer to the git repo object
 */
git_repository
*init_git()
{
  git_buf buf = GIT_BUF_INIT_CONST(NULL, 0);
  git_repository *repo;

  if (git_libgit2_init() < 0) {
    l("Failed to initalize libgit2, proceeding without git functionality enabled.");
    return NULL;
  }

  if (git_repository_discover(&buf, ".", 0, NULL) < 0) {
    l("Failed to discover git repo: %s", git_error_last()->message);
    return NULL;
  }

  if (git_repository_open(&repo, buf.ptr) < 0) {
    l("Failed to open git repo: %s", git_error_last()->message);
    git_buf_dispose(&buf);
    return NULL;
  }

  /* get rid of object containing git repo path and return the repo */
  git_buf_dispose(&buf);
  return repo;
}

/**
 * @brief check for any existing stashes in the provided git repo
 *
 * @param repo git repo to check for existing stashes
 * @return 1 if stashes found 0 otherwise
 */
int
has_stashes(git_repository *repo)
{
	git_reference *stash = NULL;
  int e;

  e = git_reference_lookup(&stash, repo, "refs/stash");
  if (e == GIT_ENOTFOUND) {
    git_error_clear();
    return 0;
  } else if (e < GIT_OK) {
    l("Error looking up stash reference: %s", git_error_last()->message);
    return 0;
  } else {
    e = 1;
  }

  git_reference_free(stash);
  return e;
}

/**
 * @brief check for any untracked changes in the current git repo
 *
 * @param repo git repository object
 * @return 1 if any untracked changes have been found 0 otherwise
 */
int
has_untracked(git_repository *repo)
{
  git_status_options opts = GIT_STATUS_OPTIONS_INIT;
  git_status_list *list = NULL;
  int r = 0;

  opts.show = GIT_STATUS_SHOW_INDEX_AND_WORKDIR;
  opts.flags = GIT_STATUS_OPT_INCLUDE_UNTRACKED |
    GIT_STATUS_OPT_RENAMES_HEAD_TO_INDEX;

  if (git_status_list_new(&list, repo, &opts) < 0) {
    l("Error checking for untacked changes: %s", git_error_last()->message);
    return 0;
  }

  /* if any changes are found return 1 */
  if (git_status_list_entrycount(list) > 0) {
    r = 1;
  }

  git_status_list_free(list);
  return r;
}
#endif

int
main(int argc, char *argv[])
{
  int code = -1;
  char face[] = { ':', 0, '|' };

  #ifdef GIT
  git_repository *repo;
  int git_ok = 0;

  if ((repo = init_git())) {
    git_ok = 1;
  }

  if (git_ok) {
    /* change the eyes depending on the current git repo's status */
    if (has_stashes(repo)) {
      face[EYES] = '8'; /* goggle eyes if we have some stashed changes */
    } else if (git_repository_is_empty(repo)) {
      face[EYES] = 'B'; /* sunglasses if we're in a new repo with no HEAD */
    } else {
      face[EYES] = ';'; /* wink when we're in a git repo */
    }

    /* change the nose depending on the current git repo's status */
    if (has_untracked(repo)) {
      face[NOSE] = '^'; /* add a little nose when there are untracked changes in the repo */
    } else if (git_repository_head_detached(repo)) {
      face[NOSE] = '-'; /* add a minus nose when the HEAD is detached */
    }
  }
  #endif

  /* get exit code from user args */
  code = atoi(argv[1] ? argv[1] : "-1");

  /* change mouth based on exit code */
  if (code >= 0) {
    switch (code) {
      case 0: face[MOUTH] = ')'; break; /* all good */
      case 130: face[MOUTH] = 'O'; break; /* Ctrl-c pressed (SIGTERM) */
      case 126: face[MOUTH] = 'P'; break; /* permission denied */
      case 127: face[MOUTH] = '/'; break; /* command not found */
      default: face[MOUTH] = '('; break; /* all other codes (usually the program saying it has failed) */
    }
  } else {
    face[MOUTH] = '|'; /* no code info */
  }

  #ifdef GIT
  git_repository_free(repo);
  git_libgit2_shutdown();
  #endif

  printf("%c%c%c", face[EYES], face[NOSE], face[MOUTH]);
}