X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fmisc%2Fcpu.c;h=3b0d278999938d58f9901aa9a9afba9181d3140c;hb=1fa88f66c121b9951db9b480eb578e98c710b977;hp=5b46fa9f789d17a77c5b6fc89fba3db2560315c0;hpb=f7ba8bf376b8f418a1c89cce0ac3aba22565e78c;p=vlc

diff --git a/src/misc/cpu.c b/src/misc/cpu.c
index 5b46fa9f78..3b0d278999 100644
--- a/src/misc/cpu.c
+++ b/src/misc/cpu.c
@@ -37,6 +37,9 @@
 #ifndef WIN32
 #include <unistd.h>
 #include <sys/wait.h>
+#include <signal.h>
+#else
+#include <errno.h>
 #endif
 
 #include "libvlc.h"
@@ -47,9 +50,9 @@
 
 #if defined( __i386__ ) || defined( __x86_64__ ) || defined( __powerpc__ ) \
  || defined( __ppc__ ) || defined( __ppc64__ ) || defined( __powerpc64__ )
+# ifndef WIN32
 static bool check_OS_capability( const char *psz_capability, pid_t pid )
 {
-#ifndef WIN32
     int status;
 
     if( pid == -1 )
@@ -65,14 +68,25 @@ static bool check_OS_capability( const char *psz_capability, pid_t pid )
     fprintf( stderr, "         some optimizations will be disabled unless "
                      "you upgrade your OS\n" );
     return false;
-#else
-# warning FIXME!
-# define fork() (errno = ENOSYS, -1)
-    (void)pid;
-    (void)psz_capability;
-    return true;
-#endif
 }
+
+#  define check_capability(name, flag, code)   \
+     do {                                      \
+        pid_t pid = fork();                    \
+        if( pid == 0 )                         \
+        {                                      \
+            signal(SIGILL, SIG_DFL);           \
+            __asm__ __volatile__ ( code : : ); \
+            _exit(0);                          \
+        }                                      \
+        if( check_OS_capability((name), pid )) \
+            i_capabilities |= (flag);          \
+     } while(0)
+
+# else /* WIN32 */
+#  define check_capability(name, flag, code)   \
+        i_capabilities |= (flag);
+# endif
 #endif
 
 /*****************************************************************************
@@ -113,18 +127,6 @@ uint32_t CPUCapabilities( void )
                          : "cc" );
 #   endif
      /* Check if the OS really supports the requested instructions */
-#   define check_capability(name, flag, code)  \
-     do {                                      \
-        pid_t pid = fork();                    \
-        if( pid == 0 )                         \
-        {                                      \
-            __asm__ __volatile__ ( code : : ); \
-            exit(0);                           \
-        }                                      \
-        if( check_OS_capability((name), pid )) \
-            i_capabilities |= (flag);          \
-     } while(0)
-
 # if defined (__i386__) && !defined (__i486__) && !defined (__i586__) \
   && !defined (__i686__) && !defined (__pentium4__) \
   && !defined (__k6__) && !defined (__athlon__) && !defined (__k8__)
@@ -269,11 +271,12 @@ out:
     pid_t pid = fork();
     if( pid == 0 )
     {
+        signal(SIGILL, SIG_DFL);
         asm volatile ("mtspr 256, %0\n\t"
                       "vand %%v0, %%v0, %%v0"
                       :
                       : "r" (-1));
-        exit(0);
+        _exit(0);
     }
 
     if( check_OS_capability( "Altivec", pid ) )
@@ -296,6 +299,48 @@ unsigned vlc_CPU (void)
     return cpu_flags;
 }
 
+const struct
+{
+    uint32_t value;
+    char name[12];
+} cap_dirs[] = {
+#if defined ( __i386__ ) || defined ( __x86_64__ )
+    { CPU_CAPABILITY_MMX,     "mmx" },
+    { CPU_CAPABILITY_MMXEXT,  "mmxext" },
+    { CPU_CAPABILITY_3DNOW,   "3dnow" },
+    { CPU_CAPABILITY_SSE,     "sse" },
+#endif
+#if defined (__ppc__) || defined (__ppc64__) || defined (__powerpc__)
+    { CPU_CAPABILITY_ALTIVEC, "altivec" },
+#endif
+#if defined (__arm__)
+    { CPU_CAPABILITY_NEON,    "arm_neon" },
+#endif
+};
+
+/**
+ * Check if a directory name contains usable plugins w.r.t. the hardware
+ * capabilities. Loading a plugin when the hardware has insufficient
+ * capabilities may lead to illegal instructions (SIGILL) and must be avoided.
+ *
+ * @param name the name of the directory (<b>not</b> the path)
+ *
+ * @return true if the hardware has sufficient capabilities or the directory
+ * does not require any special capability; false if the running hardware has
+ * insufficient capabilities.
+ */
+bool vlc_CPU_CheckPluginDir (const char *name)
+{
+    const unsigned flags = vlc_CPU ();
+    for (size_t i = 0; i < sizeof (cap_dirs) / sizeof (cap_dirs[0]); i++)
+    {
+        if (strcmp (name, cap_dirs[i].name))
+            continue;
+        return (flags & cap_dirs[i].value) != 0;
+    }
+    return true;
+}
+
 static vlc_memcpy_t pf_vlc_memcpy = memcpy;
 static vlc_memset_t pf_vlc_memset = memset;