Commit 5ecd1fec authored by Nick Mathewson's avatar Nick Mathewson 🤹
Browse files

Move horrible-emergency handling into torerr.[ch] 

Previously we had code like this for bad things happening from
signal handlers, but it makes sense to use the same logic to handle
cases when something is happening at a level too low for log.c to be
involved.

My raw_assert*() stuff now uses this code.
parent 8865972a

src/common/backtrace.c

+1 −1
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ 
#include "common/compat.h"

#include "common/util.h"

#include "common/torlog.h"

#include "common/torerr.h"



#ifdef HAVE_EXECINFO_H

#include <execinfo.h>
@@ -245,4 +246,3 @@ clean_up_backtrace_handler(void) 


  tor_free(bt_version);

}

src/common/compat_time.c

+1 −0
Original line number Diff line number Diff line
@@ -34,6 +34,7 @@ 
#include <mach/mach_time.h>

#endif



#include "common/torerr.h"

#include "common/torlog.h"

#include "common/util.h"

#include "common/container.h"

src/common/include.am

+2 −0
Original line number Diff line number Diff line
@@ -99,6 +99,7 @@ LIBOR_A_SRC = \ 
  src/common/sandbox.c					\

  src/common/storagedir.c				\

  src/common/token_bucket.c				\

  src/common/torerr.c					\

  src/common/workqueue.c				\

  $(libor_extra_source)					\

  $(threads_impl_source)				\
@@ -201,6 +202,7 @@ COMMONHEADERS = \ 
  src/common/testsupport.h			\

  src/common/timers.h				\

  src/common/token_bucket.h			\

  src/common/torerr.c				\

  src/common/torint.h				\

  src/common/torlog.h				\

  src/common/tortls.h				\

src/common/log.c

+16 −73
Original line number Diff line number Diff line
@@ -34,6 +34,8 @@ 
#define LOG_PRIVATE

#include "common/torlog.h"

#include "common/container.h"

#include "common/torerr.h"



#ifdef HAVE_ANDROID_LOG_H

#include <android/log.h>

#endif // HAVE_ANDROID_LOG_H.
@@ -265,6 +267,7 @@ void 
set_log_time_granularity(int granularity_msec)

{

  log_time_granularity = granularity_msec;

  tor_log_sigsafe_err_set_granularity(granularity_msec);

}



/** Helper: Write the standard prefix for log lines to a
@@ -631,71 +634,6 @@ tor_log(int severity, log_domain_mask_t domain, const char *format, ...) 
  va_end(ap);

}



/** Maximum number of fds that will get notifications if we crash */

#define MAX_SIGSAFE_FDS 8

/** Array of fds to log crash-style warnings to. */

static int sigsafe_log_fds[MAX_SIGSAFE_FDS] = { STDERR_FILENO };

/** The number of elements used in sigsafe_log_fds */

static int n_sigsafe_log_fds = 1;



/** Write <b>s</b> to each element of sigsafe_log_fds. Return 0 on success, -1

 * on failure. */

static int

tor_log_err_sigsafe_write(const char *s)

{

  int i;

  ssize_t r;

  size_t len = strlen(s);

  int err = 0;

  for (i=0; i < n_sigsafe_log_fds; ++i) {

    r = write(sigsafe_log_fds[i], s, len);

    err += (r != (ssize_t)len);

  }

  return err ? -1 : 0;

}



/** Given a list of string arguments ending with a NULL, writes them

 * to our logs and to stderr (if possible).  This function is safe to call

 * from within a signal handler. */

void

tor_log_err_sigsafe(const char *m, ...)

{

  va_list ap;

  const char *x;

  char timebuf[33];

  time_t now = time(NULL);



  if (!m)

    return;

  if (log_time_granularity >= 2000) {

    int g = log_time_granularity / 1000;

    now -= now % g;

  }

  timebuf[0] = now < 0 ? '-' : ' ';

  if (now < 0) now = -now;

  timebuf[1] = '\0';

  format_dec_number_sigsafe(now, timebuf+1, sizeof(timebuf)-1);

  tor_log_err_sigsafe_write("\n=========================================="

                             "================== T=");

  tor_log_err_sigsafe_write(timebuf);

  tor_log_err_sigsafe_write("\n");

  tor_log_err_sigsafe_write(m);

  va_start(ap, m);

  while ((x = va_arg(ap, const char*))) {

    tor_log_err_sigsafe_write(x);

  }

  va_end(ap);

}



/** Set *<b>out</b> to a pointer to an array of the fds to log errors to from

 * inside a signal handler. Return the number of elements in the array. */

int

tor_log_get_sigsafe_err_fds(const int **out)

{

  *out = sigsafe_log_fds;

  return n_sigsafe_log_fds;

}



/** Helper function; return true iff the <b>n</b>-element array <b>array</b>

 * contains <b>item</b>. */

static int
@@ -717,11 +655,14 @@ tor_log_update_sigsafe_err_fds(void) 
  const logfile_t *lf;

  int found_real_stderr = 0;



  int fds[TOR_SIGSAFE_LOG_MAX_FDS];

  int n_fds;



  LOCK_LOGS();

  /* Reserve the first one for stderr. This is safe because when we daemonize,

   * we dup2 /dev/null to stderr, */

  sigsafe_log_fds[0] = STDERR_FILENO;

  n_sigsafe_log_fds = 1;

  fds[0] = STDERR_FILENO;

  n_fds = 1;



  for (lf = logfiles; lf; lf = lf->next) {

     /* Don't try callback to the control port, or syslogs: We can't
@@ -735,22 +676,24 @@ tor_log_update_sigsafe_err_fds(void) 
      if (lf->fd == STDERR_FILENO)

        found_real_stderr = 1;

      /* Avoid duplicates */

      if (int_array_contains(sigsafe_log_fds, n_sigsafe_log_fds, lf->fd))

      if (int_array_contains(fds, n_fds, lf->fd))

        continue;

      sigsafe_log_fds[n_sigsafe_log_fds++] = lf->fd;

      if (n_sigsafe_log_fds == MAX_SIGSAFE_FDS)

      fds[n_fds++] = lf->fd;

      if (n_fds == TOR_SIGSAFE_LOG_MAX_FDS)

        break;

    }

  }



  if (!found_real_stderr &&

      int_array_contains(sigsafe_log_fds, n_sigsafe_log_fds, STDOUT_FILENO)) {

      int_array_contains(fds, n_fds, STDOUT_FILENO)) {

    /* Don't use a virtual stderr when we're also logging to stdout. */

    raw_assert(n_sigsafe_log_fds >= 2); /* Don't tor_assert inside log fns */

    sigsafe_log_fds[0] = sigsafe_log_fds[--n_sigsafe_log_fds];

    raw_assert(n_fds >= 2); /* Don't tor_assert inside log fns */

    fds[0] = fds[--n_fds];

  }



  UNLOCK_LOGS();



  tor_log_set_sigsafe_err_fds(fds, n_fds);

}



/** Add to <b>out</b> a copy of every currently configured log file name. Used

src/common/sandbox.c

+2 −2
Original line number Diff line number Diff line
@@ -34,6 +34,7 @@ 


#include "common/sandbox.h"

#include "common/container.h"

#include "common/torerr.h"

#include "common/torlog.h"

#include "common/torint.h"

#include "common/util.h"
@@ -1974,4 +1975,3 @@ sandbox_disable_getaddrinfo_cache(void) 
{

}

#endif /* !defined(USE_LIBSECCOMP) */