Double magic with substr

[p5sagit/p5-mst-13.2.git] / util.c

diff --git a/util.c b/util.c
index 37e913e..a6b5c1c 100644 (file)
--- a/util.c
+++ b/util.c
@@ -178,11 +178,11 @@ Perl_safesysrealloc(Malloc_t where,MEM_SIZE size)
     ptr = (Malloc_t)PerlMem_realloc(where,size);
     PERL_ALLOC_CHECK(ptr);
 
-    DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%"UVxf": (%05ld) rfree\n",PTR2UV(where),(long)PL_an++));
-    DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%"UVxf": (%05ld) realloc %ld bytes\n",PTR2UV(ptr),(long)PL_an++,(long)size));
-
-    if (ptr != NULL) {
+    /* MUST do this fixup first, before doing ANYTHING else, as anything else
+       might allocate memory/free/move memory, and until we do the fixup, it
+       may well be chasing (and writing to) free memory.  */
 #ifdef PERL_TRACK_MEMPOOL
+    if (ptr != NULL) {
        struct perl_memory_debug_header *const header
            = (struct perl_memory_debug_header *)ptr;
 
@@ -198,7 +198,17 @@ Perl_safesysrealloc(Malloc_t where,MEM_SIZE size)
        header->prev->next = header;
 
         ptr = (Malloc_t)((char*)ptr+sTHX);
+    }
 #endif
+
+    /* In particular, must do that fixup above before logging anything via
+     *printf(), as it can reallocate memory, which can cause SEGVs.  */
+
+    DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%"UVxf": (%05ld) rfree\n",PTR2UV(where),(long)PL_an++));
+    DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%"UVxf": (%05ld) realloc %ld bytes\n",PTR2UV(ptr),(long)PL_an++,(long)size));
+
+
+    if (ptr != NULL) {
        return ptr;
     }
     else if (PL_nomemok)
@@ -1422,7 +1432,6 @@ Perl_croak_nocontext(const char *pat, ...)
 {
     dTHX;
     va_list args;
-    PERL_ARGS_ASSERT_CROAK_NOCONTEXT;
     va_start(args, pat);
     vcroak(pat, &args);
     /* NOTREACHED */
@@ -3001,6 +3010,7 @@ Perl_wait4pid(pTHX_ Pid_t pid, int *statusp, int flags)
 #endif
     if (result < 0 && errno == EINTR) {
        PERL_ASYNC_CHECK();
+       errno = EINTR; /* reset in case a signal handler changed $! */
     }
     return result;
 }