/*

 * GIT - The information manager from hell

 *

 * Copyright (C) Linus Torvalds, 2005

 */

#include "git-compat-util.h"

#include "gettext.h"

#include "trace2.h"

#include "strbuf.h"

static void vfreportf(FILE *f, const char *prefix, const char *err, va_list params)

{

  char msg[4096];

  char *p, *pend = msg + sizeof(msg);

  size_t prefix_len = strlen(prefix);

  if (sizeof(msg) <= prefix_len) {

    fprintf(stderr, "BUG!!! too long a prefix '%s'\n", prefix);

    abort();

  }

  memcpy(msg, prefix, prefix_len);

  p = msg + prefix_len;

  if (vsnprintf(p, pend - p, err, params) < 0) {

    fprintf(stderr, _("error: unable to format message: %s\n"),

      err);

    *p = '\0'; /* vsnprintf() failed, clip at prefix */

  }

  for (; p != pend - 1 && *p; p++) {

    if (iscntrl(*p) && *p != '\t' && *p != '\n')

      *p = '?';

  }

  *(p++) = '\n'; /* we no longer need a NUL */

  fflush(f);

  write_in_full(fileno(f), msg, p - msg);

}

static void vreportf(const char *prefix, const char *err, va_list params)

{

  vfreportf(stderr, prefix, err, params);

}

static NORETURN void usage_builtin(const char *err, va_list params)

{

  vreportf(_("usage: "), err, params);

  /*

   * When we detect a usage error *before* the command dispatch in

   * cmd_main(), we don't know what verb to report.  Force it to this

   * to facilitate post-processing.

   */

  trace2_cmd_name("_usage_");

  /*

   * Currently, the (err, params) are usually just the static usage

   * string which isn't very useful here.  Usually, the call site

   * manually calls fprintf(stderr,...) with the actual detailed

   * syntax error before calling usage().

   *

   * TODO It would be nice to update the call sites to pass both

   * the static usage string and the detailed error message.

   */

  exit(129);

}

static void die_message_builtin(const char *err, va_list params)

{

  if (!err)

    return;

  trace2_cmd_error_va(err, params);

  vreportf(_("fatal: "), err, params);

}

/*

 * We call trace2_cmd_error_va() in the below functions first and

 * expect it to va_copy 'params' before using it (because an 'ap' can

 * only be walked once).

 */

static NORETURN void die_builtin(const char *err, va_list params)

{

  report_fn die_message_fn = get_die_message_routine();

  die_message_fn(err, params);

  exit(128);

}

static void error_builtin(const char *err, va_list params)

{

  trace2_cmd_error_va(err, params);

  vreportf(_("error: "), err, params);

}

static void warn_builtin(const char *warn, va_list params)

{

  trace2_cmd_error_va(warn, params);

  vreportf(_("warning: "), warn, params);

}

static int die_is_recursing_builtin(void)

{

  static int dying;

  /*

   * Just an arbitrary number X where "a < x < b" where "a" is

   * "maximum number of pthreads we'll ever plausibly spawn" and

   * "b" is "something less than Inf", since the point is to

   * prevent infinite recursion.

   */

  static const int recursion_limit = 1024;

  dying++;

  if (dying > recursion_limit) {

    return 1;

  } else if (dying == 2) {

    warning("die() called many times. Recursion error or racy threaded death!");

    return 0;

  } else {

    return 0;

  }

}

/* If we are in a dlopen()ed .so write to a global variable would segfault

 * (ugh), so keep things static. */

static NORETURN_PTR report_fn usage_routine = usage_builtin;

static NORETURN_PTR report_fn die_routine = die_builtin;

static report_fn die_message_routine = die_message_builtin;

static report_fn error_routine = error_builtin;

static report_fn warn_routine = warn_builtin;

static int (*die_is_recursing)(void) = die_is_recursing_builtin;

void set_die_routine(NORETURN_PTR report_fn routine)

{

  die_routine = routine;

}

report_fn get_die_message_routine(void)

{

  return die_message_routine;

}

void set_error_routine(report_fn routine)

{

  error_routine = routine;

}

report_fn get_error_routine(void)

{

  return error_routine;

}

void set_warn_routine(report_fn routine)

{

  warn_routine = routine;

}

report_fn get_warn_routine(void)

{

  return warn_routine;

}

void set_die_is_recursing_routine(int (*routine)(void))

{

  die_is_recursing = routine;

}

void NORETURN usagef(const char *err, ...)

{

  va_list params;

  va_start(params, err);

  usage_routine(err, params);

  va_end(params);

}

void NORETURN usage(const char *err)

{

  usagef("%s", err);

}

static void show_usage_if_asked_helper(const char *err, ...)

{

  va_list params;

  va_start(params, err);

  vfreportf(stdout, _("usage: "), err, params);

  va_end(params);

  exit(129);

}

void show_usage_if_asked(int ac, const char **av, const char *err)

{

  if (ac == 2 && (!strcmp(av[1], "-h") ||

      !strcmp(av[1], "--help-all")))

    show_usage_if_asked_helper(err);

}

void NORETURN die(const char *err, ...)

{

  va_list params;

  if (die_is_recursing()) {

    fputs("fatal: recursion detected in die handler\n", stderr);

    exit(128);

  }

  va_start(params, err);

  die_routine(err, params);

  va_end(params);

}

static const char *fmt_with_err(char *buf, int n, const char *fmt)

{

  char str_error[256], *err;

  size_t i, j;

  err = strerror(errno);

  for (i = j = 0; err[i] && j < sizeof(str_error) - 1; ) {

    if ((str_error[j++] = err[i++]) != '%')

      continue;

    if (j < sizeof(str_error) - 1) {

      str_error[j++] = '%';

    } else {

      /* No room to double the '%', so we overwrite it with

       * '\0' below */

      j--;

      break;

    }

  }

  str_error[j] = 0;

  /* Truncation is acceptable here */

  snprintf(buf, n, "%s: %s", fmt, str_error);

  return buf;

}

void NORETURN die_errno(const char *fmt, ...)

{

  char buf[1024];

  va_list params;

  if (die_is_recursing()) {

    fputs("fatal: recursion detected in die_errno handler\n",

      stderr);

    exit(128);

  }

  va_start(params, fmt);

  die_routine(fmt_with_err(buf, sizeof(buf), fmt), params);

  va_end(params);

}

#undef die_message

int die_message(const char *err, ...)

{

  va_list params;

  va_start(params, err);

  die_message_routine(err, params);

  va_end(params);

  return 128;

}

#undef die_message_errno

int die_message_errno(const char *fmt, ...)

{

  char buf[1024];

  va_list params;

  va_start(params, fmt);

  die_message_routine(fmt_with_err(buf, sizeof(buf), fmt), params);

  va_end(params);

  return 128;

}

#undef error_errno

int error_errno(const char *fmt, ...)

{

  char buf[1024];

  va_list params;

  va_start(params, fmt);

  error_routine(fmt_with_err(buf, sizeof(buf), fmt), params);

  va_end(params);

  return -1;

}

#undef error

int error(const char *err, ...)

{

  va_list params;

  va_start(params, err);

  error_routine(err, params);

  va_end(params);

  return -1;

}

void warning_errno(const char *warn, ...)

{

  char buf[1024];

  va_list params;

  va_start(params, warn);

  warn_routine(fmt_with_err(buf, sizeof(buf), warn), params);

  va_end(params);

}

void warning(const char *warn, ...)

{

  va_list params;

  va_start(params, warn);

  warn_routine(warn, params);

  va_end(params);

}

/* Only set this, ever, from t/helper/, when verifying that bugs are caught. */

int BUG_exit_code;

static void BUG_vfl_common(const char *file, int line, const char *fmt,

         va_list params)

{

  char prefix[256];

  /* truncation via snprintf is OK here */

  snprintf(prefix, sizeof(prefix), "BUG: %s:%d: ", file, line);

  vreportf(prefix, fmt, params);

}

static NORETURN void BUG_vfl(const char *file, int line, const char *fmt, va_list params)

{

  va_list params_copy;

  static int in_bug;

  va_copy(params_copy, params);

  BUG_vfl_common(file, line, fmt, params);

  if (in_bug)

    abort();

  in_bug = 1;

  trace2_cmd_error_va(fmt, params_copy);

  if (BUG_exit_code)

    exit(BUG_exit_code);

  abort();

}

NORETURN void BUG_fl(const char *file, int line, const char *fmt, ...)

{

  va_list ap;

  bug_called_must_BUG = 0;

  va_start(ap, fmt);

  BUG_vfl(file, line, fmt, ap);

  va_end(ap);

}

int bug_called_must_BUG;

void bug_fl(const char *file, int line, const char *fmt, ...)

{

  va_list ap;

  bug_called_must_BUG = 1;

  va_start(ap, fmt);

  BUG_vfl_common(file, line, fmt, ap);

  va_end(ap);

  va_start(ap, fmt);

  trace2_cmd_error_va(fmt, ap);

  va_end(ap);

}

NORETURN void you_still_use_that(const char *command_name, const char *hint)

{

  struct strbuf percent_encoded = STRBUF_INIT;

  strbuf_add_percentencode(&percent_encoded,

         command_name,

         STRBUF_ENCODE_SLASH);

  fprintf(stderr,

    _("'%s' is nominated for removal.\n"), command_name);

  if (hint)

    fputs(hint, stderr);

  fprintf(stderr,

    _("If you still use this command, here's what you can do:\n"

      "\n"

      "- read https://git-scm.com/docs/BreakingChanges.html\n"

      "- check if anyone has discussed this on the mailing\n"

      "  list and if they came up with something that can\n"

      "  help you: https://lore.kernel.org/git/?q=%s\n"

      "- send an email to <git@vger.kernel.org> to let us\n"

      "  know that you still use this command and were unable\n"

      "  to determine a suitable replacement\n"

      "\n"),

    percent_encoded.buf);

  strbuf_release(&percent_encoded);

  die(_("refusing to run without --i-still-use-this"));

}