2002-11-08 Jeff Johnston <jjohnstn@redhat.com>

[deliverable/binutils-gdb.git] / gdb / infptrace.c

diff --git a/gdb/infptrace.c b/gdb/infptrace.c
index 9815e05ef0b89a04321d32d3b266a7ab996169c7..777a5b491ed7c0e013eb5ab54f77cf6f24ddd150 100644 (file)
--- a/gdb/infptrace.c
+++ b/gdb/infptrace.c
@@ -1,6 +1,6 @@
 /* Low level Unix child interface to ptrace, for GDB when running under Unix.
-   Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998,
-   1999, 2000, 2001
+   Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996,
+   1998, 1999, 2000, 2001, 2002
    Free Software Foundation, Inc.
 
    This file is part of GDB.
@@ -480,6 +480,11 @@ store_inferior_registers (int regno)
 #endif /* !defined (FETCH_INFERIOR_REGISTERS).  */
 \f
 
+/* Set an upper limit on alloca.  */
+#ifndef GDB_MAX_ALLOCA
+#define GDB_MAX_ALLOCA 0x1000
+#endif
+
 #if !defined (CHILD_XFER_MEMORY)
 /* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
    in the NEW_SUN_PTRACE case.  It ought to be straightforward.  But
@@ -497,8 +502,7 @@ store_inferior_registers (int regno)
 
 int
 child_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
-                  struct mem_attrib *attrib ATTRIBUTE_UNUSED,
-                  struct target_ops *target)
+                  struct mem_attrib *attrib, struct target_ops *target)
 {
   int i;
   /* Round starting address down to longword boundary.  */
@@ -506,9 +510,20 @@ child_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
   /* Round ending address up; get number of longwords that makes.  */
   int count = ((((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
               / sizeof (PTRACE_XFER_TYPE));
+  int alloc = count * sizeof (PTRACE_XFER_TYPE);
+  PTRACE_XFER_TYPE *buffer;
+  struct cleanup *old_chain = NULL;
+
   /* Allocate buffer of that many longwords.  */
-  PTRACE_XFER_TYPE *buffer =
-    (PTRACE_XFER_TYPE *) alloca (count * sizeof (PTRACE_XFER_TYPE));
+  if (len < GDB_MAX_ALLOCA)
+    {
+      buffer = (PTRACE_XFER_TYPE *) alloca (alloc);
+    }
+  else
+    {
+      buffer = (PTRACE_XFER_TYPE *) xmalloc (alloc);
+      old_chain = make_cleanup (xfree, buffer);
+    }
 
   if (write)
     {
@@ -573,6 +588,8 @@ child_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
              len);
     }
 
+  if (old_chain != NULL)
+    do_cleanups (old_chain);
   return len;
 }
 \f