use the gnulib random_r function

ChangeLog

-Thu Jan 21 19:04:12 GMT 2009 Daniel P. Berrange <berrange@redhat.com>
+Thu Jan 21 19:44:12 GMT 2009 Daniel P. Berrange <berrange@redhat.com>
+
+	Use the GNULIB random_r function
+	* Makefile.maint: print 4 lines of context when complaining
+	about prohibited POSIX apis
+	* src/libvirt.c: Initialize random number generator
+	* src/util.c, src/util.h: Generate API for random number gen
+	* src/uuid.: Use generic random number generator API
+
+Thu Jan 21 19:41:12 GMT 2009 Daniel P. Berrange <berrange@redhat.com>
 
 	Remove use of non-reentrant POSIX api calls
 	* configure.in: Check for  strtok_r getmntent_r getgrnam_r getpwuid_r

Makefile.maint

@@ -117,7 +117,7 @@ sc_prohibit_nonreentrant:
 	@fail=0 ; \
 	for i in $(NON_REENTRANT) ; \
 	do \
-	   grep -nE "\<$$i\>[:space:]*\(" $$($(VC_LIST_EXCEPT)) && \
+	   grep --before 2 --after 1 -nE "\<$$i\>[:space:]*\(" $$($(VC_LIST_EXCEPT)) && \
 	     fail=1 && echo "$(ME): use $${i}_r, not $${i}" || : ; \
 	done ; \
 	exit $$fail

src/libvirt.c

@@ -21,6 +21,7 @@
 #ifdef HAVE_SYS_WAIT_H
 #include <sys/wait.h>
 #endif
+#include <time.h>
 
 #include <libxml/parser.h>
 #include <libxml/xpath.h>
@@ -257,7 +258,8 @@ virInitialize(void)
     initialized = 1;
 
     if (virThreadInitialize() < 0 ||
-        virErrorInitialize() < 0)
+        virErrorInitialize() < 0 ||
+        virRandomInitialize(time(NULL) ^ getpid()))
         return -1;
 
 #ifdef ENABLE_DEBUG
@@ -332,23 +334,19 @@ DllMain (HINSTANCE instance ATTRIBUTE_UNUSED,
 {
     switch (reason) {
     case DLL_PROCESS_ATTACH:
-        fprintf(stderr, "Initializing DLL\n");
         virInitialize();
         break;
 
     case DLL_THREAD_ATTACH:
-        fprintf(stderr, "Thread start\n");
         /* Nothing todo in libvirt yet */
         break;
 
     case DLL_THREAD_DETACH:
-        fprintf(stderr, "Thread exit\n");
         /* Release per-thread local data */
         virThreadOnExit();
         break;
 
     case DLL_PROCESS_DETACH:
-        fprintf(stderr, "Process exit\n");
         /* Don't bother releasing per-thread data
            since (hopefully) windows cleans up
            everything on process exit */

src/util.c

@@ -32,6 +32,7 @@
 #include <fcntl.h>
 #include <errno.h>
 #include <poll.h>
+#include <time.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/ioctl.h>
@@ -59,6 +60,7 @@
 #include "buf.h"
 #include "util.h"
 #include "memory.h"
+#include "threads.h"
 
 #ifndef NSIG
 # define NSIG 32
@@ -1285,9 +1287,9 @@ void virGenerateMacAddr(const unsigned char *prefix,
     addr[0] = prefix[0];
     addr[1] = prefix[1];
     addr[2] = prefix[2];
-    addr[3] = (int)(256*(rand()/(RAND_MAX+1.0)));
-    addr[4] = (int)(256*(rand()/(RAND_MAX+1.0)));
-    addr[5] = (int)(256*(rand()/(RAND_MAX+1.0)));
+    addr[3] = virRandom(256);
+    addr[4] = virRandom(256);
+    addr[5] = virRandom(256);
 }
 
 
@@ -1436,6 +1438,36 @@ int virKillProcess(pid_t pid, int sig)
 }
 
 
+static char randomState[128];
+static struct random_data randomData;
+static virMutex randomLock;
+
+int virRandomInitialize(unsigned int seed)
+{
+    if (virMutexInit(&randomLock) < 0)
+        return -1;
+
+    if (initstate_r(seed,
+                    randomState,
+                    sizeof(randomState),
+                    &randomData) < 0)
+        return -1;
+
+    return 0;
+}
+
+int virRandom(int max)
+{
+    int32_t ret;
+
+    virMutexLock(&randomLock);
+    random_r(&randomData, &ret);
+    virMutexUnlock(&randomLock);
+
+    return (int) ((double)max * ((double)ret / (double)RAND_MAX));
+}
+
+
 #ifdef HAVE_GETPWUID_R
 char *virGetUserDirectory(virConnectPtr conn,
                           uid_t uid)

src/util.h

@@ -177,4 +177,7 @@ char *virGetUserDirectory(virConnectPtr conn,
                           uid_t uid);
 #endif
 
+int virRandomInitialize(unsigned int seed);
+int virRandom(int max);
+
 #endif /* __VIR_UTIL_H__ */

src/uuid.c

@@ -35,6 +35,7 @@
 
 #include "c-ctype.h"
 #include "internal.h"
+#include "util.h"
 
 #define qemudLog(level, msg...) fprintf(stderr, msg)
 
@@ -74,9 +75,8 @@ static int
 virUUIDGeneratePseudoRandomBytes(unsigned char *buf,
                                  int buflen)
 {
-    srand(time(NULL));
     while (buflen > 0) {
-        *buf = (int) (255.0 * (rand() / (double) RAND_MAX));
+        *buf = virRandom(256);
         buflen--;
     }