2003-07-28 Daniel Jacobowitz <drow@mvista.com>

[strace] / io.c

diff --git a/io.c b/io.c
index 893ee619aac67ebfa8b8d001d06351d9566773c0..65b48fdb96541e24d4c03b03ee1d3a604eea01f1 100644 (file)
--- a/io.c
+++ b/io.c
@@ -231,6 +231,18 @@ struct tcb *tcp;
 #endif /* FREEBSD */
 
 #ifdef LINUX
+
+/* The SH4 ABI does allow long longs in odd-numbered registers, but
+   does not allow them to be split between registers and memory - and
+   there are only four argument registers for normal functions.  As a
+   result pread takes an extra padding argument before the offset.  This
+   was changed late in the 2.4 series (around 2.4.20).  */
+#if defined(SH)
+#define PREAD_OFFSET_ARG 4
+#else
+#define PREAD_OFFSET_ARG 3
+#endif
+
 int
 sys_pread(tcp)
 struct tcb *tcp;
@@ -242,9 +254,9 @@ struct tcb *tcp;
                        tprintf("%#lx", tcp->u_arg[1]);
                else
                        printstr(tcp, tcp->u_arg[1], tcp->u_rval);
-               ALIGN64 (tcp, 3); /* PowerPC alignment restriction */
+               ALIGN64 (tcp, PREAD_OFFSET_ARG); /* PowerPC alignment restriction */
                tprintf(", %lu, %llu", tcp->u_arg[2],
-                       *(unsigned long long *)&tcp->u_arg[3]);
+                       *(unsigned long long *)&tcp->u_arg[PREAD_OFFSET_ARG]);
        }
        return 0;
 }
@@ -256,9 +268,9 @@ struct tcb *tcp;
        if (entering(tcp)) {
                tprintf("%ld, ", tcp->u_arg[0]);
                printstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
-               ALIGN64 (tcp, 3); /* PowerPC alignment restriction */
+               ALIGN64 (tcp, PREAD_OFFSET_ARG); /* PowerPC alignment restriction */
                tprintf(", %lu, %llu", tcp->u_arg[2],
-                       *(unsigned long long *)&tcp->u_arg[3]);
+                       *(unsigned long long *)&tcp->u_arg[PREAD_OFFSET_ARG]);
        }
        return 0;
 }