added function for generating random ascii strings, and improved the test program to test for this as well

git-svn-id: http://svn.code.sf.net/p/retroshare/code/trunk@3992 b45a01b8-16f6-495d-af2f-9b41ad6348cc

libretroshare/src/tests/general/random_test.cc

@@ -132,6 +132,7 @@ int main(int argc, char **argv)
 	feenableexcept(FE_INVALID) ;
 	feenableexcept(FE_DIVBYZERO) ;
 #endif
+	std::cerr << "Generating random 64 chars string (run that again to test that it's changing): " << RSRandom::random_alphaNumericString(64) << std::endl;
 	int nt = 10 ;	// number of threads.
 	std::vector<myThread *> threads(nt,(myThread*)NULL) ;
 

libretroshare/src/util/rsrandom.cc

@@ -1,10 +1,14 @@
 #include <stdlib.h>
+#include <string>
+#include <unistd.h>
 #include "rsrandom.h"
 
 uint32_t RSRandom::index = 0 ;
 std::vector<uint32_t> RSRandom::MT(RSRandom::N,0u) ;
 RsMutex RSRandom::rndMtx ;
-static bool auto_seed = RSRandom::seed(time(NULL)) ;
+
+// If this does not compile on windows, use a ifdef to keep this on linux plz.
+static bool auto_seed = RSRandom::seed( (time(NULL) + pthread_self()*0x1293fe + (getpid()^0x113ef76b))^0x18e34a12 ) ;
 
 bool RSRandom::seed(uint32_t s) 
 {
@@ -71,3 +75,13 @@ double RSRandom::random_f64()
 	return random_u64() / (double)(~(uint64_t)0) ;
 }
 
+std::string RSRandom::random_alphaNumericString(uint32_t len)
+{
+	std::string s = "" ;
+
+	for(int i=0;i<len;++i)
+		s += (char)( (random_u32()%94) + 33) ;
+
+	return s ;
+}
+

libretroshare/src/util/rsrandom.h

@@ -44,6 +44,8 @@ class RSRandom
 
 		static bool     seed(uint32_t s) ;
 
+		static std::string random_alphaNumericString(uint32_t length) ; 
+
 	private:
 		static RsMutex rndMtx ;