semihosting: Split out semihost_sys_flen

The ARM-specific SYS_FLEN isn't really something that can be
reused by other semihosting apis, but there are parts that can
reused for the implementation of semihost_sys_fstat.

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

1 files changed, 49 insertions, 0 deletions

diff --git a/semihosting/syscalls.c b/semihosting/syscalls.c
index 1f1baf7e2d..fff9550c89 100644
--- a/semihosting/syscalls.c
+++ b/semihosting/syscalls.c
@@ -127,6 +127,12 @@ static void gdb_isatty(CPUState *cs, gdb_syscall_complete_cb complete,
     gdb_do_syscall(complete, "isatty,%x", (target_ulong)gf->hostfd);
 }
 
+static void gdb_fstat(CPUState *cs, gdb_syscall_complete_cb complete,
+                      GuestFD *gf, target_ulong addr)
+{
+    gdb_do_syscall(complete, "fstat,%x,%x", (target_ulong)gf->hostfd, addr);
+}
+
 /*
  * Host semihosting syscall implementations.
  */
@@ -259,6 +265,18 @@ static void host_isatty(CPUState *cs, gdb_syscall_complete_cb complete,
     complete(cs, ret, ret ? 0 : errno);
 }
 
+static void host_flen(CPUState *cs, gdb_syscall_complete_cb complete,
+                      GuestFD *gf)
+{
+    struct stat buf;
+
+    if (fstat(gf->hostfd, &buf) < 0) {
+        complete(cs, -1, errno);
+    } else {
+        complete(cs, buf.st_size, 0);
+    }
+}
+
 /*
  * Static file semihosting syscall implementations.
  */
@@ -311,6 +329,12 @@ static void staticfile_lseek(CPUState *cs, gdb_syscall_complete_cb complete,
     }
 }
 
+static void staticfile_flen(CPUState *cs, gdb_syscall_complete_cb complete,
+                            GuestFD *gf)
+{
+    complete(cs, gf->staticfile.len, 0);
+}
+
 /*
  * Syscall entry points.
  */
@@ -473,3 +497,28 @@ void semihost_sys_isatty(CPUState *cs, gdb_syscall_complete_cb complete, int fd)
         g_assert_not_reached();
     }
 }
+
+void semihost_sys_flen(CPUState *cs, gdb_syscall_complete_cb fstat_cb,
+                       gdb_syscall_complete_cb flen_cb, int fd,
+                       target_ulong fstat_addr)
+{
+    GuestFD *gf = get_guestfd(fd);
+
+    if (!gf) {
+        flen_cb(cs, -1, EBADF);
+        return;
+    }
+    switch (gf->type) {
+    case GuestFDGDB:
+        gdb_fstat(cs, fstat_cb, gf, fstat_addr);
+        break;
+    case GuestFDHost:
+        host_flen(cs, flen_cb, gf);
+        break;
+    case GuestFDStatic:
+        staticfile_flen(cs, flen_cb, gf);
+        break;
+    default:
+        g_assert_not_reached();
+    }
+}