Attempt to use dladdr() to get the pathname of the executable image if

it's available and works.

svn path=/trunk/; revision=27812

9 files changed, 78 insertions, 10 deletions

diff --git a/capinfos.c b/capinfos.c
index 1eb6b6a7e3..8d09fcdf9e 100644
--- a/capinfos.c
+++ b/capinfos.c
@@ -302,7 +302,8 @@ main(int argc, char *argv[])
 #ifdef HAVE_PLUGINS
   /* Register wiretap plugins */
 
-    if ((init_progfile_dir_error = init_progfile_dir(argv[0]))) {
+    if ((init_progfile_dir_error = init_progfile_dir(argv[0],
+        (const void *)main))) {
 		g_warning("capinfos: init_progfile_dir(): %s", init_progfile_dir_error);
 		g_free(init_progfile_dir_error);
     } else {
diff --git a/configure.in b/configure.in
index 75ad236a73..d110126399 100644
--- a/configure.in
+++ b/configure.in
@@ -676,6 +676,41 @@ else
   have_plugins=no
 fi
 
+#
+# Check whether we can use dladdr to find the pathname of an executable.
+#
+AC_MSG_CHECKING(whether dladdr can be used to find the pathname of an executable)
+ac_save_CFLAGS="$CFLAGS"
+ac_save_LIBS="$LIBS"
+CFLAGS="$CFLAGS $GLIB_CFLAGS"
+LIBS="$GLIB_LIBS $LIBS"
+AC_TRY_RUN([
+#include <stdio.h>
+#include <dlfcn.h>
+
+int
+main(void)
+{
+	Dl_info info;
+
+	if (!dladdr((const void *)main, &info))
+		return 1;	/* failure */
+	if (info.dli_fname[0] != '/')
+		return 1;	/* not an absolute path - failure */
+	return 0;		/* assume success */
+}
+], ac_cv_dladdr_finds_executable_path=yes, ac_cv_dladdr_finds_executable_path=no,
+   [echo $ac_n "cross compiling; assumed OK... $ac_c"
+    ac_cv_dladdr_finds_executable_path=yes])
+CFLAGS="$ac_save_CFLAGS"
+LIBS="$ac_save_LIBS"
+if test x$ac_cv_dladdr_finds_executable_path = xyes
+then
+  AC_DEFINE(DLADDR_FINDS_EXECUTABLE_PATH, 1, [Define if dladdr can be used to find the path of the executable])
+fi
+AC_MSG_RESULT($ac_cv_dladdr_finds_executable_path)
+
+
 dnl IGE Mac integration check
 AC_MSG_CHECKING(whether to use IGE Mac integration functions)
 
diff --git a/dftest.c b/dftest.c
index 84b198cbde..7fbadd8bc7 100644
--- a/dftest.c
+++ b/dftest.c
@@ -75,7 +75,8 @@ main(int argc, char **argv)
 	/*
 	 * Attempt to get the pathname of the executable file.
 	 */
-	init_progfile_dir_error = init_progfile_dir(argv[0]);
+	init_progfile_dir_error = init_progfile_dir(argv[0],
+	    (const void *)main);
 	if (init_progfile_dir_error != NULL) {
 		fprintf(stderr, "dftest: Can't get pathname of dftest program: %s.\n",
 		    init_progfile_dir_error);
diff --git a/editcap.c b/editcap.c
index 8c541e1b9c..9f2fb28d57 100644
--- a/editcap.c
+++ b/editcap.c
@@ -424,7 +424,8 @@ main(int argc, char *argv[])
 
 #ifdef HAVE_PLUGINS
   /* Register wiretap plugins */
-  if ((init_progfile_dir_error = init_progfile_dir(argv[0]))) {
+  if ((init_progfile_dir_error = init_progfile_dir(argv[0],
+                                                   (const void *)main))) {
     g_warning("capinfos: init_progfile_dir(): %s", init_progfile_dir_error);
     g_free(init_progfile_dir_error);
   } else {
diff --git a/epan/filesystem.c b/epan/filesystem.c
index 5b522d6b76..79312d3a05 100644
--- a/epan/filesystem.c
+++ b/epan/filesystem.c
@@ -55,9 +55,12 @@
 #include <tchar.h>
 #include <shlobj.h>
 #include <wsutil/unicode-utils.h>
-#else
+#else /* _WIN32 */
+#ifdef DLADDR_FINDS_EXECUTABLE_PATH
+#include <dlfcn.h>
+#endif /* DLADDR_FINDS_EXECUTABLE_PATH */
 #include <pwd.h>
-#endif
+#endif /* _WIN32 */
 
 #include "filesystem.h"
 #include "report_err.h"
@@ -246,6 +249,10 @@ init_progfile_dir(const char *arg0
 #ifdef _WIN32
 	_U_
 #endif
+, const void *main_addr
+#if defined(_WIN32) || !defined(DLADDR_FINDS_EXECUTABLE_PATH)
+	_U_
+#endif
 )
 {
 	char *dir_end;
@@ -334,6 +341,9 @@ init_progfile_dir(const char *arg0
 		    msg, error);
 	}
 #else
+#ifdef DLADDR_FINDS_EXECUTABLE_PATH
+	Dl_info info;
+#endif
 	char *prog_pathname;
 	char *curdir;
 	long path_max;
@@ -355,6 +365,22 @@ init_progfile_dir(const char *arg0
 	    && !started_with_special_privs())
 		running_in_build_directory_flag = TRUE;
 
+#ifdef DLADDR_FINDS_EXECUTABLE_PATH
+	/*
+	 * Try to use dladdr() to find the pathname of the executable.
+	 */
+	if (dladdr(main_addr, &info) && info.dli_fname[0] == '/') {
+		/*
+		 * dladdr() succeeded, and we got an absolute path
+		 * for the module containing main() (I don't know
+		 * whether it's guaranteed to return an absolute path
+		 * on all platforms), so we'll use that as the
+		 * executable image's path.
+		 */
+		prog_pathname = g_strdup(info.dli_fname);
+	} else
+#endif
+	{
 	/*
 	 * Try to figure out the directory in which the currently running
 	 * program resides, given the argv[0] it was started with.  That
@@ -456,6 +482,7 @@ init_progfile_dir(const char *arg0
 			return g_strdup("PATH isn't set");
 		}
 	}
+	}
 
 	/*
 	 * OK, we have what we think is the pathname
diff --git a/epan/filesystem.h b/epan/filesystem.h
index a97f8d7880..01c2a60d3e 100644
--- a/epan/filesystem.h
+++ b/epan/filesystem.h
@@ -36,7 +36,7 @@
  * and save it for future use.  Returns NULL on success, and a
  * g_mallocated string containing an error on failure.
  */
-extern char *init_progfile_dir(const char *arg0);
+extern char *init_progfile_dir(const char *arg0, const void *main_addr);
 
 /*
  * Get the directory in which the program resides.
diff --git a/gtk/main.c b/gtk/main.c
index 7ac984b17a..14a96ac837 100644
--- a/gtk/main.c
+++ b/gtk/main.c
@@ -1808,7 +1808,8 @@ main(int argc, char *argv[])
   /*
    * Attempt to get the pathname of the executable file.
    */
-  init_progfile_dir_error = init_progfile_dir(argv[0]);
+  init_progfile_dir_error = init_progfile_dir(argv[0],
+                                              (const void *)main);
 
   /* initialize the funnel mini-api */
   initialize_funnel_ops();
diff --git a/rawshark.c b/rawshark.c
index 9dc10bcb7b..5b3d07af23 100644
--- a/rawshark.c
+++ b/rawshark.c
@@ -31,7 +31,7 @@
  * - Opens a specified file or named pipe
  * - Applies a specfied DLT or "decode as" encapsulation
  * - Reads frames prepended with a libpcap packet header.
- * - Prints a status line, followed by  fields from a specified list.
+ * - Prints a status line, followed by fields from a specified list.
  */
 
 #ifdef HAVE_CONFIG_H
@@ -460,7 +460,8 @@ main(int argc, char *argv[])
   /*
    * Attempt to get the pathname of the executable file.
    */
-  init_progfile_dir_error = init_progfile_dir(argv[0]);
+  init_progfile_dir_error = init_progfile_dir(argv[0],
+                                              (const void *)main);
   if (init_progfile_dir_error != NULL) {
     fprintf(stderr, "rawshark: Can't get pathname of rawshark program: %s.\n",
             init_progfile_dir_error);
diff --git a/tshark.c b/tshark.c
index 9ce3f57582..688b0a9836 100644
--- a/tshark.c
+++ b/tshark.c
@@ -773,7 +773,8 @@ main(int argc, char *argv[])
   /*
    * Attempt to get the pathname of the executable file.
    */
-  init_progfile_dir_error = init_progfile_dir(argv[0]);
+  init_progfile_dir_error = init_progfile_dir(argv[0],
+                                              (const void *)main);
   if (init_progfile_dir_error != NULL) {
     fprintf(stderr, "tshark: Can't get pathname of tshark program: %s.\n",
             init_progfile_dir_error);