File signal-and-panic-improvements.diff of Package alpine

##########################################################################
# This patch generates a backtrace on abort and if core file dumping is
# enabled, it also write the backtrace to a temporary file. 
##########################################################################

#
# Manual page of the used glibc backtrace function:
#
http://www.gnu.org/software/libc/manual/html_node/Backtraces.html

--- alpine-0.999/alpine/alpine.c
+++ alpine-0.999/alpine/alpine.c
@@ -15,6 +15,8 @@ static char rcsid[] = "$Id: alpine.c 615
  * ========================================================================
  */
 
+#include <execinfo.h>
+#include <sys/resource.h>
 #include "headers.h"
 
 #include "../pith/newmail.h"
@@ -3274,6 +3275,46 @@ panic(char *message)
     fprintf(stderr, "\n\n%s\n", buf);
 #endif
 
+    {
+	void *array[40];
+	size_t size, i;
+	char **strings;
+	struct rlimit rlim;
+
+	size = backtrace (array, sizeof(array));
+	strings = backtrace_symbols (array, size);
+
+	fprintf(stderr, "Backtrace (%zd stack frames):\n", size);
+	for (i = 0; i < size; i++)
+		fprintf(stderr, "%s\n", strings[i]);
+
+	if (getrlimit(RLIMIT_CORE, &rlim))
+		perror("getrlimit(RLIMIT_CORE)");
+	else {
+		if (rlim.rlim_cur != 0) {
+			umask(S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH);
+			char filename[] = "/tmp/alpine-backtrace.XXXXXX";
+			int fd = mkstemp(filename);
+			if (fd == -1)
+				perror("mkstemp for backtrace");
+			else {
+				FILE* btf = fdopen(fd, "w");
+				if (!btf)
+					perror("fdopen for backtrace");
+				else {
+					fprintf(btf, "%s\n", buf);
+					fprintf(btf, "Backtrace (%zd stack frames):\n", size);
+					for (i = 0; i < size; i++)
+						fprintf(btf, "%s\n", strings[i]);
+					fclose(btf);
+					fprintf(stderr, "Saved backtrace in: %s\n", filename);
+				}
+				close(fd);
+			}
+		}
+	}
+    }
+
 #ifdef DEBUG
     if(debugfile){
 	save_debug_on_crash(debugfile, recent_keystroke);