remove printf from signal handlers

use AC_SEARCH_LIB in configure.ac (shorter code)
replace '-lm -lcrypto -lz' by  @LIBS@ in Makefile.in and AC_CHECK_LIB macros in configure.ac
replace NO_BACKTRACE by HAVE_EXECINFO_H

Makefile.in

@@ -6,8 +6,8 @@ CPPFLAGS=@CPPFLAGS@
 DEFS=@DEFS@
 COMPILE_FLAGS=${CFLAGS} ${CPPFLAGS} ${DEFS} -Wall -Wextra -Werror -Wno-deprecated -fno-strict-aliasing -fno-omit-frame-pointer -ggdb
 
-EXTRA_LIBS=@EXTRA_LIBS@
-LOCAL_LDFLAGS=-lm -lcrypto -lz -lssl -rdynamic -ggdb ${EXTRA_LIBS}
+EXTRA_LIBS=-lssl @LIBS@ @EXTRA_LIBS@
+LOCAL_LDFLAGS=-rdynamic -ggdb ${EXTRA_LIBS}
 LINK_FLAGS=${LDFLAGS} ${LOCAL_LDFLAGS}
 
 HEADERS= ${srcdir}/constants.h  ${srcdir}/include.h  ${srcdir}/interface.h  ${srcdir}/LICENSE.h  ${srcdir}/loop.h  ${srcdir}/mtproto-client.h  ${srcdir}/mtproto-common.h  ${srcdir}/net.h  ${srcdir}/no-preview.h  ${srcdir}/queries.h  ${srcdir}/structures.h  ${srcdir}/telegram.h  ${srcdir}/tree.h ${srcdir}/config.h ${srcdir}/binlog.h ${srcdir}/tools.h ${srcdir}/lua-tg.h

config.h

@@ -13,6 +13,9 @@
 /* Define to 1 if you have the `endpwent' function. */
 #define HAVE_ENDPWENT 1
 
+/* Define to 1 if you have the <execinfo.h> header file. */
+#define HAVE_EXECINFO_H 1
+
 /* Define to 1 if you have the <fcntl.h> header file. */
 #define HAVE_FCNTL_H 1
 
@@ -31,6 +34,9 @@
 /* Define to 1 if you have the `m' library (-lm). */
 #define HAVE_LIBM 1
 
+/* Define to 1 if you have the `z' library (-lz). */
+#define HAVE_LIBZ 1
+
 /* Define to 1 if you have the <luaconf.h> header file. */
 #define HAVE_LUACONF_H 1
 

config.h.in

@@ -12,6 +12,9 @@
 /* Define to 1 if you have the `endpwent' function. */
 #undef HAVE_ENDPWENT
 
+/* Define to 1 if you have the <execinfo.h> header file. */
+#undef HAVE_EXECINFO_H
+
 /* Define to 1 if you have the <fcntl.h> header file. */
 #undef HAVE_FCNTL_H
 
@@ -30,6 +33,9 @@
 /* Define to 1 if you have the `m' library (-lm). */
 #undef HAVE_LIBM
 
+/* Define to 1 if you have the `z' library (-lz). */
+#undef HAVE_LIBZ
+
 /* Define to 1 if you have the <luaconf.h> header file. */
 #undef HAVE_LUACONF_H
 

configure.ac

@@ -10,25 +10,12 @@ AC_PROG_CC
 
 # Checks for libraries.
 AC_CHECK_LIB([m], [sqrt])
+AC_SEARCH_LIBS([clock_gettime], [rt])
+AC_SEARCH_LIBS([backtrace], [execinfo])
+AC_CHECK_LIB([z], [inflate])
 AC_CHECK_LIB([crypto], [AES_set_encrypt_key])
-
 EXTRA_LIBS=""
 
-BT=
-AC_CHECK_FUNC([backtrace],
-  [
-    BT=1
-  ],
-  [
-  ]
-)
-
-if test "x$BT" = "x" ; then
-  AC_CHECK_LIB([execinfo], [backtrace],
-  [ EXTRA_LIBS="${EXTRA_LIBS} -lexecinfo" ; ],
-  [ CFLAGS="${CFLAGS} -DNO_BACKTRACE" ; ])
-fi
-
 AC_CHECK_LIB([readline], [rl_save_prompt], 
   [
     AC_DEFINE([READLINE_GNU], [1], [Use gnu libreadline])
@@ -41,14 +28,6 @@ AC_CHECK_LIB([readline], [rl_save_prompt],
   ]
 )
 
-AC_CHECK_LIB([rt], [clock_gettime], 
-  [
-    [ EXTRA_LIBS="${EXTRA_LIBS} -lrt" ; ]
-  ],
-  [
-  ]
-)
-
 AC_MSG_CHECKING([for libconfig])
 AC_ARG_ENABLE(libconfig,[--enable-libconfig/--disable-libconfig],
   [ 
@@ -100,7 +79,7 @@ AC_ARG_ENABLE(liblua,[--enable-liblua/--disable-liblua],
   ])
     
 # Checks for header files.
-AC_CHECK_HEADERS([fcntl.h malloc.h netdb.h stdlib.h string.h unistd.h arpa/inet.h mach/mach.h netinet/in.h sys/file.h sys/socket.h termios.h])
+AC_CHECK_HEADERS([execinfo.h fcntl.h malloc.h netdb.h stdlib.h string.h unistd.h arpa/inet.h mach/mach.h netinet/in.h sys/file.h sys/socket.h termios.h])
 
 # Checks for typedefs, structures, and compiler characteristics.
 AC_TYPE_SIZE_T

main.c

@@ -38,7 +38,8 @@
 #include <sys/stat.h>
 #include <time.h>
 #include <fcntl.h>
-#ifndef NO_BACKTRACE
+
+#ifdef HAVE_EXECINFO_H
 #include <execinfo.h>
 #endif
 #include <signal.h>
@@ -420,7 +421,7 @@ void args_parse (int argc, char **argv) {
   }
 }
 
-#ifndef NO_BACKTRACE
+#ifdef HAVE_EXECINFO_H
 void print_backtrace (void) {
   void *buffer[255];
   const int calls = backtrace (buffer, sizeof (buffer) / sizeof (void *));
@@ -428,21 +429,27 @@ void print_backtrace (void) {
 }
 #else
 void print_backtrace (void) {
-  printf ("No libexec. Backtrace disabled\n");
+  write (1, "No libexec. Backtrace disabled\n", 32);
 }
 #endif
 
-void sig_handler (int signum) {
+void sig_segv_handler (int signum __attribute__ ((unused))) {
   set_terminal_attributes ();
-  printf ("Signal %d received\n", signum);
+  write (1, "SIGSEGV received\n", 18);
   print_backtrace ();
-  exit(EXIT_FAILURE);
+  exit (EXIT_FAILURE);
 }
 
+void sig_abrt_handler (int signum __attribute__ ((unused))) {
+  set_terminal_attributes ();
+  write (1, "SIGABRT received\n", 18);
+  print_backtrace ();
+  exit (EXIT_FAILURE);
+}
 
 int main (int argc, char **argv) {
-  signal (SIGSEGV, sig_handler);
-  signal (SIGABRT, sig_handler);
+  signal (SIGSEGV, sig_segv_handler);
+  signal (SIGABRT, sig_abrt_handler);
 
   log_level = 10;