X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=libinterfork%2Finterfork.c;h=e9dce9bfb188d7f60032d04a5f2b9d9dfd5f9f2b;hb=fbca6b624335eef18c8d86194aeb101a720168f4;hp=e57b7e593c06664a5cf73313185ef6cea3462935;hpb=2d99476b851d50b376bafb2bc12994d8b0950538;p=ust.git

diff --git a/libinterfork/interfork.c b/libinterfork/interfork.c
index e57b7e5..e9dce9b 100644
--- a/libinterfork/interfork.c
+++ b/libinterfork/interfork.c
@@ -19,6 +19,11 @@
 #include <dlfcn.h>
 #include <unistd.h>
 #include <stdio.h>
+#include <signal.h>
+#include "usterr.h"
+
+extern void ust_fork(void);
+extern void ust_potential_exec(void);
 
 pid_t fork(void)
 {
@@ -26,19 +31,71 @@ pid_t fork(void)
 
 	pid_t retval;
 
+	int result;
+	sigset_t all_sigs;
+	sigset_t orig_sigs;
+
 	if(plibc_func == NULL) {
 		plibc_func = dlsym(RTLD_NEXT, "fork");
 		if(plibc_func == NULL) {
 			fprintf(stderr, "libcwrap: unable to find fork\n");
-			return NULL;
+			return -1;
 		}
 	}
 
-	printf("IN FORK!\n");
+	/* Disable interrupts. This is to avoid that the child
+	 * intervenes before it is properly setup for tracing. It is
+	 * safer to disable all signals, because then we know we are not
+	 * breaking anything by restoring the original mask.
+	 */
+
+	/* FIXME:
+		- only do this if tracing is active
+	*/
+
+	/* Disable signals */
+	sigfillset(&all_sigs);
+	result = sigprocmask(SIG_BLOCK, &all_sigs, &orig_sigs);
+	if(result == -1) {
+		PERROR("sigprocmask");
+		return -1;
+	}
+
+	/* Do the real fork */
 	retval = plibc_func();
 
-	if(retval == 0)
+	if(retval == 0) {
+		/* child */
 		ust_fork();
+	}
+
+	/* Restore signals */
+	result = sigprocmask(SIG_BLOCK, &orig_sigs, NULL);
+	if(result == -1) {
+		PERROR("sigprocmask");
+		return -1;
+	}
+
+	return retval;
+}
+
+int execve(const char *filename, char *const argv[], char *const envp[])
+{
+	static int (*plibc_func)(const char *filename, char *const argv[], char *const envp[]) = NULL;
+
+	pid_t retval;
+
+	if(plibc_func == NULL) {
+		plibc_func = dlsym(RTLD_NEXT, "execve");
+		if(plibc_func == NULL) {
+			fprintf(stderr, "libcwrap: unable to find execve\n");
+			return -1;
+		}
+	}
+
+	ust_potential_exec();
+
+	retval = plibc_func(filename, argv, envp);
 
 	return retval;
 }