binfmt: translate symbolic links correctly with realpath

Change-Id: Ic0eeac9de40a8e1082c83b442829ac28f68bff04
Signed-off-by: Julien Isorce <j.isorce@samsung.com>
Signed-off-by: Yury Usishchev <y.usishchev@samsung.com>

1 files changed, 11 insertions, 14 deletions

diff --git a/linux-user/binfmt.c b/linux-user/binfmt.c
index 458f136fb..26bb38814 100644
--- a/linux-user/binfmt.c
+++ b/linux-user/binfmt.c
@@ -4,10 +4,7 @@
 #include <libgen.h>
 #include <string.h>
 #include <stdlib.h>
-
-#ifdef __x86_64__
-#define ARCH_NAME "x86_64"
-#endif
+#include <limits.h>
 
 int main(int argc, char **argv, char **envp)
 {
@@ -31,18 +28,20 @@ int main(int argc, char **argv, char **envp)
     binfmt[0] = '\0';
     /* Now argv[0] is the real qemu binary name */
 
-#ifdef ARCH_NAME
     {
-        char *hostbin;
-        char *guestarch;
         int r;
+        char buf[PATH_MAX];
+        char *hostbin;
+        char *path;
 
-        guestarch = strrchr(argv[0], '-') ;
-        if (!guestarch) {
-            goto skip;
+        /* Follow symbolic link if any. */
+        path = realpath(argv[1], buf);
+        if (path == NULL) {
+            /* Error occured, falling back to original argument */
+            path = argv[1];
         }
-        guestarch++;
-        r = asprintf(&hostbin, "/emul/" ARCH_NAME "-for-%s/%s", guestarch, argv[1]);
+
+        r = asprintf(&hostbin, "/emul/%s", path);
         if ((r > 0) && !access(hostbin, X_OK)) {
             /*
              * We found a host binary replacement for the non-host binary. Let's
@@ -51,8 +50,6 @@ int main(int argc, char **argv, char **envp)
             return execve(hostbin, &argv[2], envp);
         }
     }
-skip:
-#endif
 
     new_argv = (char **)malloc((argc + 2) * sizeof(*new_argv));
     if (argc > 3) {