semihosting: Split out semihost_sys_rename

Split out the non-ARM specific portions of SYS_RENAME to a
reusable function.

Reviewed-by: Luc Michel <lmichel@kalray.eu>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

include/semihosting/syscalls.h

@@ -52,4 +52,8 @@ void semihost_sys_flen(CPUState *cs, gdb_syscall_complete_cb fstat_cb,
 void semihost_sys_remove(CPUState *cs, gdb_syscall_complete_cb complete,
                          target_ulong fname, target_ulong fname_len);
 
+void semihost_sys_rename(CPUState *cs, gdb_syscall_complete_cb complete,
+                         target_ulong oname, target_ulong oname_len,
+                         target_ulong nname, target_ulong nname_len);
+
 #endif /* SEMIHOSTING_SYSCALLS_H */

semihosting/arm-compat-semi.c

@@ -492,26 +492,7 @@ void do_common_semihosting(CPUState *cs)
         GET_ARG(1);
         GET_ARG(2);
         GET_ARG(3);
-        if (use_gdb_syscalls()) {
-            gdb_do_syscall(common_semi_cb, "rename,%s,%s",
-                           arg0, (int)arg1 + 1, arg2, (int)arg3 + 1);
-        } else {
-            char *s2;
-
-            s = lock_user_string(arg0);
-            if (!s) {
-                goto do_fault;
-            }
-            s2 = lock_user_string(arg2);
-            if (!s2) {
-                unlock_user(s, arg0, 0);
-                goto do_fault;
-            }
-            ret = rename(s, s2);
-            unlock_user(s2, arg2, 0);
-            unlock_user(s, arg0, 0);
-            common_semi_cb(cs, ret, ret ? errno : 0);
-        }
+        semihost_sys_rename(cs, common_semi_cb, arg0, arg1 + 1, arg2, arg3 + 1);
         break;
 
     case TARGET_SYS_CLOCK:

semihosting/syscalls.c

@@ -145,6 +145,26 @@ static void gdb_remove(CPUState *cs, gdb_syscall_complete_cb complete,
     gdb_do_syscall(complete, "unlink,%s", fname, len);
 }
 
+static void gdb_rename(CPUState *cs, gdb_syscall_complete_cb complete,
+                       target_ulong oname, target_ulong oname_len,
+                       target_ulong nname, target_ulong nname_len)
+{
+    int olen, nlen;
+
+    olen = validate_strlen(cs, oname, oname_len);
+    if (olen < 0) {
+        complete(cs, -1, -olen);
+        return;
+    }
+    nlen = validate_strlen(cs, nname, nname_len);
+    if (nlen < 0) {
+        complete(cs, -1, -nlen);
+        return;
+    }
+
+    gdb_do_syscall(complete, "rename,%s,%s", oname, olen, nname, nlen);
+}
+
 /*
  * Host semihosting syscall implementations.
  */
@@ -307,6 +327,32 @@ static void host_remove(CPUState *cs, gdb_syscall_complete_cb complete,
     unlock_user(p, fname, 0);
 }
 
+static void host_rename(CPUState *cs, gdb_syscall_complete_cb complete,
+                        target_ulong oname, target_ulong oname_len,
+                        target_ulong nname, target_ulong nname_len)
+{
+    CPUArchState *env G_GNUC_UNUSED = cs->env_ptr;
+    char *ostr, *nstr;
+    int ret;
+
+    ret = validate_lock_user_string(&ostr, cs, oname, oname_len);
+    if (ret < 0) {
+        complete(cs, -1, -ret);
+        return;
+    }
+    ret = validate_lock_user_string(&nstr, cs, nname, nname_len);
+    if (ret < 0) {
+        unlock_user(ostr, oname, 0);
+        complete(cs, -1, -ret);
+        return;
+    }
+
+    ret = rename(ostr, nstr);
+    complete(cs, ret, ret ? errno : 0);
+    unlock_user(ostr, oname, 0);
+    unlock_user(nstr, nname, 0);
+}
+
 /*
  * Static file semihosting syscall implementations.
  */
@@ -562,3 +608,14 @@ void semihost_sys_remove(CPUState *cs, gdb_syscall_complete_cb complete,
         host_remove(cs, complete, fname, fname_len);
     }
 }
+
+void semihost_sys_rename(CPUState *cs, gdb_syscall_complete_cb complete,
+                         target_ulong oname, target_ulong oname_len,
+                         target_ulong nname, target_ulong nname_len)
+{
+    if (use_gdb_syscalls()) {
+        gdb_rename(cs, complete, oname, oname_len, nname, nname_len);
+    } else {
+        host_rename(cs, complete, oname, oname_len, nname, nname_len);
+    }
+}